FreeBSD/Linux Kernel Cross Reference
sys/contrib/edk2/Include/Library/BaseLib.h

     /** @file
       Provides string functions, linked list functions, math functions, synchronization
       functions, file path functions, and CPU architecture-specific functions.
     
     Copyright (c) 2006 - 2019, Intel Corporation. All rights reserved.<BR>
     Portions copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>
     Copyright (c) Microsoft Corporation.<BR>
     Portions Copyright (c) 2020, Hewlett Packard Enterprise Development LP. All rights reserved.<BR>
     
    SPDX-License-Identifier: BSD-2-Clause-Patent
    
    **/
    
    #ifndef __BASE_LIB__
    #define __BASE_LIB__
    
    //
    // Definitions for architecture-specific types
    //
    #if   defined (MDE_CPU_IA32)
    ///
    /// The IA-32 architecture context buffer used by SetJump() and LongJump().
    ///
    typedef struct {
      UINT32                            Ebx;
      UINT32                            Esi;
      UINT32                            Edi;
      UINT32                            Ebp;
      UINT32                            Esp;
      UINT32                            Eip;
      UINT32                            Ssp;
    } BASE_LIBRARY_JUMP_BUFFER;
    
    #define BASE_LIBRARY_JUMP_BUFFER_ALIGNMENT 4
    
    #endif // defined (MDE_CPU_IA32)
    
    #if defined (MDE_CPU_X64)
    ///
    /// The x64 architecture context buffer used by SetJump() and LongJump().
    ///
    typedef struct {
      UINT64                            Rbx;
      UINT64                            Rsp;
      UINT64                            Rbp;
      UINT64                            Rdi;
      UINT64                            Rsi;
      UINT64                            R12;
      UINT64                            R13;
      UINT64                            R14;
      UINT64                            R15;
      UINT64                            Rip;
      UINT64                            MxCsr;
      UINT8                             XmmBuffer[160]; ///< XMM6-XMM15.
      UINT64                            Ssp;
    } BASE_LIBRARY_JUMP_BUFFER;
    
    #define BASE_LIBRARY_JUMP_BUFFER_ALIGNMENT 8
    
    #endif // defined (MDE_CPU_X64)
    
    #if defined (MDE_CPU_EBC)
    ///
    /// The EBC context buffer used by SetJump() and LongJump().
    ///
    typedef struct {
      UINT64                            R0;
      UINT64                            R1;
      UINT64                            R2;
      UINT64                            R3;
      UINT64                            IP;
    } BASE_LIBRARY_JUMP_BUFFER;
    
    #define BASE_LIBRARY_JUMP_BUFFER_ALIGNMENT 8
    
    #endif // defined (MDE_CPU_EBC)
    
    #if defined (MDE_CPU_ARM)
    
    typedef struct {
      UINT32    R3;  ///< A copy of R13.
      UINT32    R4;
      UINT32    R5;
      UINT32    R6;
      UINT32    R7;
      UINT32    R8;
      UINT32    R9;
      UINT32    R10;
      UINT32    R11;
      UINT32    R12;
      UINT32    R14;
    } BASE_LIBRARY_JUMP_BUFFER;
    
    #define BASE_LIBRARY_JUMP_BUFFER_ALIGNMENT 4
    
    #endif  // defined (MDE_CPU_ARM)
    
    #if defined (MDE_CPU_AARCH64)
    typedef struct {
     // GP regs
     UINT64    X19;
     UINT64    X20;
     UINT64    X21;
     UINT64    X22;
     UINT64    X23;
     UINT64    X24;
     UINT64    X25;
     UINT64    X26;
     UINT64    X27;
     UINT64    X28;
     UINT64    FP;
     UINT64    LR;
     UINT64    IP0;
   
     // FP regs
     UINT64    D8;
     UINT64    D9;
     UINT64    D10;
     UINT64    D11;
     UINT64    D12;
     UINT64    D13;
     UINT64    D14;
     UINT64    D15;
   } BASE_LIBRARY_JUMP_BUFFER;
   
   #define BASE_LIBRARY_JUMP_BUFFER_ALIGNMENT 8
   
   #endif  // defined (MDE_CPU_AARCH64)
   
   #if defined (MDE_CPU_RISCV64)
   ///
   /// The RISC-V architecture context buffer used by SetJump() and LongJump().
   ///
   typedef struct {
     UINT64                            RA;
     UINT64                            S0;
     UINT64                            S1;
     UINT64                            S2;
     UINT64                            S3;
     UINT64                            S4;
     UINT64                            S5;
     UINT64                            S6;
     UINT64                            S7;
     UINT64                            S8;
     UINT64                            S9;
     UINT64                            S10;
     UINT64                            S11;
     UINT64                            SP;
   } BASE_LIBRARY_JUMP_BUFFER;
   
   #define BASE_LIBRARY_JUMP_BUFFER_ALIGNMENT 8
   
   #endif // defined (MDE_CPU_RISCV64)
   
   //
   // String Services
   //
   
   
   /**
     Returns the length of a Null-terminated Unicode string.
   
     This function is similar as strlen_s defined in C11.
   
     If String is not aligned on a 16-bit boundary, then ASSERT().
   
     @param  String   A pointer to a Null-terminated Unicode string.
     @param  MaxSize  The maximum number of Destination Unicode
                      char, including terminating null char.
   
     @retval 0        If String is NULL.
     @retval MaxSize  If there is no null character in the first MaxSize characters of String.
     @return The number of characters that percede the terminating null character.
   
   **/
   UINTN
   EFIAPI
   StrnLenS (
     IN CONST CHAR16              *String,
     IN UINTN                     MaxSize
     );
   
   /**
     Returns the size of a Null-terminated Unicode string in bytes, including the
     Null terminator.
   
     This function returns the size of the Null-terminated Unicode string
     specified by String in bytes, including the Null terminator.
   
     If String is not aligned on a 16-bit boundary, then ASSERT().
   
     @param  String   A pointer to a Null-terminated Unicode string.
     @param  MaxSize  The maximum number of Destination Unicode
                      char, including the Null terminator.
   
     @retval 0  If String is NULL.
     @retval (sizeof (CHAR16) * (MaxSize + 1))
                If there is no Null terminator in the first MaxSize characters of
                String.
     @return The size of the Null-terminated Unicode string in bytes, including
             the Null terminator.
   
   **/
   UINTN
   EFIAPI
   StrnSizeS (
     IN CONST CHAR16              *String,
     IN UINTN                     MaxSize
     );
   
   /**
     Copies the string pointed to by Source (including the terminating null char)
     to the array pointed to by Destination.
   
     This function is similar as strcpy_s defined in C11.
   
     If Destination is not aligned on a 16-bit boundary, then ASSERT().
     If Source is not aligned on a 16-bit boundary, then ASSERT().
   
     If an error is returned, then the Destination is unmodified.
   
     @param  Destination              A pointer to a Null-terminated Unicode string.
     @param  DestMax                  The maximum number of Destination Unicode
                                      char, including terminating null char.
     @param  Source                   A pointer to a Null-terminated Unicode string.
   
     @retval RETURN_SUCCESS           String is copied.
     @retval RETURN_BUFFER_TOO_SMALL  If DestMax is NOT greater than StrLen(Source).
     @retval RETURN_INVALID_PARAMETER If Destination is NULL.
                                      If Source is NULL.
                                      If PcdMaximumUnicodeStringLength is not zero,
                                       and DestMax is greater than
                                       PcdMaximumUnicodeStringLength.
                                      If DestMax is 0.
     @retval RETURN_ACCESS_DENIED     If Source and Destination overlap.
   **/
   RETURN_STATUS
   EFIAPI
   StrCpyS (
     OUT CHAR16       *Destination,
     IN  UINTN        DestMax,
     IN  CONST CHAR16 *Source
     );
   
   /**
     Copies not more than Length successive char from the string pointed to by
     Source to the array pointed to by Destination. If no null char is copied from
     Source, then Destination[Length] is always set to null.
   
     This function is similar as strncpy_s defined in C11.
   
     If Length > 0 and Destination is not aligned on a 16-bit boundary, then ASSERT().
     If Length > 0 and Source is not aligned on a 16-bit boundary, then ASSERT().
   
     If an error is returned, then the Destination is unmodified.
   
     @param  Destination              A pointer to a Null-terminated Unicode string.
     @param  DestMax                  The maximum number of Destination Unicode
                                      char, including terminating null char.
     @param  Source                   A pointer to a Null-terminated Unicode string.
     @param  Length                   The maximum number of Unicode characters to copy.
   
     @retval RETURN_SUCCESS           String is copied.
     @retval RETURN_BUFFER_TOO_SMALL  If DestMax is NOT greater than
                                      MIN(StrLen(Source), Length).
     @retval RETURN_INVALID_PARAMETER If Destination is NULL.
                                      If Source is NULL.
                                      If PcdMaximumUnicodeStringLength is not zero,
                                       and DestMax is greater than
                                       PcdMaximumUnicodeStringLength.
                                      If DestMax is 0.
     @retval RETURN_ACCESS_DENIED     If Source and Destination overlap.
   **/
   RETURN_STATUS
   EFIAPI
   StrnCpyS (
     OUT CHAR16       *Destination,
     IN  UINTN        DestMax,
     IN  CONST CHAR16 *Source,
     IN  UINTN        Length
     );
   
   /**
     Appends a copy of the string pointed to by Source (including the terminating
     null char) to the end of the string pointed to by Destination.
   
     This function is similar as strcat_s defined in C11.
   
     If Destination is not aligned on a 16-bit boundary, then ASSERT().
     If Source is not aligned on a 16-bit boundary, then ASSERT().
   
     If an error is returned, then the Destination is unmodified.
   
     @param  Destination              A pointer to a Null-terminated Unicode string.
     @param  DestMax                  The maximum number of Destination Unicode
                                      char, including terminating null char.
     @param  Source                   A pointer to a Null-terminated Unicode string.
   
     @retval RETURN_SUCCESS           String is appended.
     @retval RETURN_BAD_BUFFER_SIZE   If DestMax is NOT greater than
                                      StrLen(Destination).
     @retval RETURN_BUFFER_TOO_SMALL  If (DestMax - StrLen(Destination)) is NOT
                                      greater than StrLen(Source).
     @retval RETURN_INVALID_PARAMETER If Destination is NULL.
                                      If Source is NULL.
                                      If PcdMaximumUnicodeStringLength is not zero,
                                       and DestMax is greater than
                                       PcdMaximumUnicodeStringLength.
                                      If DestMax is 0.
     @retval RETURN_ACCESS_DENIED     If Source and Destination overlap.
   **/
   RETURN_STATUS
   EFIAPI
   StrCatS (
     IN OUT CHAR16       *Destination,
     IN     UINTN        DestMax,
     IN     CONST CHAR16 *Source
     );
   
   /**
     Appends not more than Length successive char from the string pointed to by
     Source to the end of the string pointed to by Destination. If no null char is
     copied from Source, then Destination[StrLen(Destination) + Length] is always
     set to null.
   
     This function is similar as strncat_s defined in C11.
   
     If Destination is not aligned on a 16-bit boundary, then ASSERT().
     If Source is not aligned on a 16-bit boundary, then ASSERT().
   
     If an error is returned, then the Destination is unmodified.
   
     @param  Destination              A pointer to a Null-terminated Unicode string.
     @param  DestMax                  The maximum number of Destination Unicode
                                      char, including terminating null char.
     @param  Source                   A pointer to a Null-terminated Unicode string.
     @param  Length                   The maximum number of Unicode characters to copy.
   
     @retval RETURN_SUCCESS           String is appended.
     @retval RETURN_BAD_BUFFER_SIZE   If DestMax is NOT greater than
                                      StrLen(Destination).
     @retval RETURN_BUFFER_TOO_SMALL  If (DestMax - StrLen(Destination)) is NOT
                                      greater than MIN(StrLen(Source), Length).
     @retval RETURN_INVALID_PARAMETER If Destination is NULL.
                                      If Source is NULL.
                                      If PcdMaximumUnicodeStringLength is not zero,
                                       and DestMax is greater than
                                       PcdMaximumUnicodeStringLength.
                                      If DestMax is 0.
     @retval RETURN_ACCESS_DENIED     If Source and Destination overlap.
   **/
   RETURN_STATUS
   EFIAPI
   StrnCatS (
     IN OUT CHAR16       *Destination,
     IN     UINTN        DestMax,
     IN     CONST CHAR16 *Source,
     IN     UINTN        Length
     );
   
   /**
     Convert a Null-terminated Unicode decimal string to a value of type UINTN.
   
     This function outputs a value of type UINTN by interpreting the contents of
     the Unicode string specified by String as a decimal number. The format of the
     input Unicode string String is:
   
                     [spaces] [decimal digits].
   
     The valid decimal digit character is in the range [0-9]. The function will
     ignore the pad space, which includes spaces or tab characters, before
     [decimal digits]. The running zero in the beginning of [decimal digits] will
     be ignored. Then, the function stops at the first character that is a not a
     valid decimal character or a Null-terminator, whichever one comes first.
   
     If String is not aligned in a 16-bit boundary, then ASSERT().
   
     If String has no valid decimal digits in the above format, then 0 is stored
     at the location pointed to by Data.
     If the number represented by String exceeds the range defined by UINTN, then
     MAX_UINTN is stored at the location pointed to by Data.
   
     If EndPointer is not NULL, a pointer to the character that stopped the scan
     is stored at the location pointed to by EndPointer. If String has no valid
     decimal digits right after the optional pad spaces, the value of String is
     stored at the location pointed to by EndPointer.
   
     @param  String                   Pointer to a Null-terminated Unicode string.
     @param  EndPointer               Pointer to character that stops scan.
     @param  Data                     Pointer to the converted value.
   
     @retval RETURN_SUCCESS           Value is translated from String.
     @retval RETURN_INVALID_PARAMETER If String is NULL.
                                      If Data is NULL.
                                      If PcdMaximumUnicodeStringLength is not
                                      zero, and String contains more than
                                      PcdMaximumUnicodeStringLength Unicode
                                      characters, not including the
                                      Null-terminator.
     @retval RETURN_UNSUPPORTED       If the number represented by String exceeds
                                      the range defined by UINTN.
   
   **/
   RETURN_STATUS
   EFIAPI
   StrDecimalToUintnS (
     IN  CONST CHAR16             *String,
     OUT       CHAR16             **EndPointer,  OPTIONAL
     OUT       UINTN              *Data
     );
   
   /**
     Convert a Null-terminated Unicode decimal string to a value of type UINT64.
   
     This function outputs a value of type UINT64 by interpreting the contents of
     the Unicode string specified by String as a decimal number. The format of the
     input Unicode string String is:
   
                     [spaces] [decimal digits].
   
     The valid decimal digit character is in the range [0-9]. The function will
     ignore the pad space, which includes spaces or tab characters, before
     [decimal digits]. The running zero in the beginning of [decimal digits] will
     be ignored. Then, the function stops at the first character that is a not a
     valid decimal character or a Null-terminator, whichever one comes first.
   
     If String is not aligned in a 16-bit boundary, then ASSERT().
   
     If String has no valid decimal digits in the above format, then 0 is stored
     at the location pointed to by Data.
     If the number represented by String exceeds the range defined by UINT64, then
     MAX_UINT64 is stored at the location pointed to by Data.
   
     If EndPointer is not NULL, a pointer to the character that stopped the scan
     is stored at the location pointed to by EndPointer. If String has no valid
     decimal digits right after the optional pad spaces, the value of String is
     stored at the location pointed to by EndPointer.
   
     @param  String                   Pointer to a Null-terminated Unicode string.
     @param  EndPointer               Pointer to character that stops scan.
     @param  Data                     Pointer to the converted value.
   
     @retval RETURN_SUCCESS           Value is translated from String.
     @retval RETURN_INVALID_PARAMETER If String is NULL.
                                      If Data is NULL.
                                      If PcdMaximumUnicodeStringLength is not
                                      zero, and String contains more than
                                      PcdMaximumUnicodeStringLength Unicode
                                      characters, not including the
                                      Null-terminator.
     @retval RETURN_UNSUPPORTED       If the number represented by String exceeds
                                      the range defined by UINT64.
   
   **/
   RETURN_STATUS
   EFIAPI
   StrDecimalToUint64S (
     IN  CONST CHAR16             *String,
     OUT       CHAR16             **EndPointer,  OPTIONAL
     OUT       UINT64             *Data
     );
   
   /**
     Convert a Null-terminated Unicode hexadecimal string to a value of type
     UINTN.
   
     This function outputs a value of type UINTN by interpreting the contents of
     the Unicode string specified by String as a hexadecimal number. The format of
     the input Unicode string String is:
   
                     [spaces][zeros][x][hexadecimal digits].
   
     The valid hexadecimal digit character is in the range [0-9], [a-f] and [A-F].
     The prefix "0x" is optional. Both "x" and "X" is allowed in "0x" prefix.
     If "x" appears in the input string, it must be prefixed with at least one 0.
     The function will ignore the pad space, which includes spaces or tab
     characters, before [zeros], [x] or [hexadecimal digit]. The running zero
     before [x] or [hexadecimal digit] will be ignored. Then, the decoding starts
     after [x] or the first valid hexadecimal digit. Then, the function stops at
     the first character that is a not a valid hexadecimal character or NULL,
     whichever one comes first.
   
     If String is not aligned in a 16-bit boundary, then ASSERT().
   
     If String has no valid hexadecimal digits in the above format, then 0 is
     stored at the location pointed to by Data.
     If the number represented by String exceeds the range defined by UINTN, then
     MAX_UINTN is stored at the location pointed to by Data.
   
     If EndPointer is not NULL, a pointer to the character that stopped the scan
     is stored at the location pointed to by EndPointer. If String has no valid
     hexadecimal digits right after the optional pad spaces, the value of String
     is stored at the location pointed to by EndPointer.
   
     @param  String                   Pointer to a Null-terminated Unicode string.
     @param  EndPointer               Pointer to character that stops scan.
     @param  Data                     Pointer to the converted value.
   
     @retval RETURN_SUCCESS           Value is translated from String.
     @retval RETURN_INVALID_PARAMETER If String is NULL.
                                      If Data is NULL.
                                      If PcdMaximumUnicodeStringLength is not
                                      zero, and String contains more than
                                      PcdMaximumUnicodeStringLength Unicode
                                      characters, not including the
                                      Null-terminator.
     @retval RETURN_UNSUPPORTED       If the number represented by String exceeds
                                      the range defined by UINTN.
   
   **/
   RETURN_STATUS
   EFIAPI
   StrHexToUintnS (
     IN  CONST CHAR16             *String,
     OUT       CHAR16             **EndPointer,  OPTIONAL
     OUT       UINTN              *Data
     );
   
   /**
     Convert a Null-terminated Unicode hexadecimal string to a value of type
     UINT64.
   
     This function outputs a value of type UINT64 by interpreting the contents of
     the Unicode string specified by String as a hexadecimal number. The format of
     the input Unicode string String is:
   
                     [spaces][zeros][x][hexadecimal digits].
   
     The valid hexadecimal digit character is in the range [0-9], [a-f] and [A-F].
     The prefix "0x" is optional. Both "x" and "X" is allowed in "0x" prefix.
     If "x" appears in the input string, it must be prefixed with at least one 0.
     The function will ignore the pad space, which includes spaces or tab
     characters, before [zeros], [x] or [hexadecimal digit]. The running zero
     before [x] or [hexadecimal digit] will be ignored. Then, the decoding starts
     after [x] or the first valid hexadecimal digit. Then, the function stops at
     the first character that is a not a valid hexadecimal character or NULL,
     whichever one comes first.
   
     If String is not aligned in a 16-bit boundary, then ASSERT().
   
     If String has no valid hexadecimal digits in the above format, then 0 is
     stored at the location pointed to by Data.
     If the number represented by String exceeds the range defined by UINT64, then
     MAX_UINT64 is stored at the location pointed to by Data.
   
     If EndPointer is not NULL, a pointer to the character that stopped the scan
     is stored at the location pointed to by EndPointer. If String has no valid
     hexadecimal digits right after the optional pad spaces, the value of String
     is stored at the location pointed to by EndPointer.
   
     @param  String                   Pointer to a Null-terminated Unicode string.
     @param  EndPointer               Pointer to character that stops scan.
     @param  Data                     Pointer to the converted value.
   
     @retval RETURN_SUCCESS           Value is translated from String.
     @retval RETURN_INVALID_PARAMETER If String is NULL.
                                      If Data is NULL.
                                      If PcdMaximumUnicodeStringLength is not
                                      zero, and String contains more than
                                      PcdMaximumUnicodeStringLength Unicode
                                      characters, not including the
                                      Null-terminator.
     @retval RETURN_UNSUPPORTED       If the number represented by String exceeds
                                      the range defined by UINT64.
   
   **/
   RETURN_STATUS
   EFIAPI
   StrHexToUint64S (
     IN  CONST CHAR16             *String,
     OUT       CHAR16             **EndPointer,  OPTIONAL
     OUT       UINT64             *Data
     );
   
   /**
     Returns the length of a Null-terminated Ascii string.
   
     This function is similar as strlen_s defined in C11.
   
     @param  String   A pointer to a Null-terminated Ascii string.
     @param  MaxSize  The maximum number of Destination Ascii
                      char, including terminating null char.
   
     @retval 0        If String is NULL.
     @retval MaxSize  If there is no null character in the first MaxSize characters of String.
     @return The number of characters that percede the terminating null character.
   
   **/
   UINTN
   EFIAPI
   AsciiStrnLenS (
     IN CONST CHAR8               *String,
     IN UINTN                     MaxSize
     );
   
   /**
     Returns the size of a Null-terminated Ascii string in bytes, including the
     Null terminator.
   
     This function returns the size of the Null-terminated Ascii string specified
     by String in bytes, including the Null terminator.
   
     @param  String   A pointer to a Null-terminated Ascii string.
     @param  MaxSize  The maximum number of Destination Ascii
                      char, including the Null terminator.
   
     @retval 0  If String is NULL.
     @retval (sizeof (CHAR8) * (MaxSize + 1))
                If there is no Null terminator in the first MaxSize characters of
                String.
     @return The size of the Null-terminated Ascii string in bytes, including the
             Null terminator.
   
   **/
   UINTN
   EFIAPI
   AsciiStrnSizeS (
     IN CONST CHAR8               *String,
     IN UINTN                     MaxSize
     );
   
   /**
     Copies the string pointed to by Source (including the terminating null char)
     to the array pointed to by Destination.
   
     This function is similar as strcpy_s defined in C11.
   
     If an error is returned, then the Destination is unmodified.
   
     @param  Destination              A pointer to a Null-terminated Ascii string.
     @param  DestMax                  The maximum number of Destination Ascii
                                      char, including terminating null char.
     @param  Source                   A pointer to a Null-terminated Ascii string.
   
     @retval RETURN_SUCCESS           String is copied.
     @retval RETURN_BUFFER_TOO_SMALL  If DestMax is NOT greater than StrLen(Source).
     @retval RETURN_INVALID_PARAMETER If Destination is NULL.
                                      If Source is NULL.
                                      If PcdMaximumAsciiStringLength is not zero,
                                       and DestMax is greater than
                                       PcdMaximumAsciiStringLength.
                                      If DestMax is 0.
     @retval RETURN_ACCESS_DENIED     If Source and Destination overlap.
   **/
   RETURN_STATUS
   EFIAPI
   AsciiStrCpyS (
     OUT CHAR8        *Destination,
     IN  UINTN        DestMax,
     IN  CONST CHAR8  *Source
     );
   
   /**
     Copies not more than Length successive char from the string pointed to by
     Source to the array pointed to by Destination. If no null char is copied from
     Source, then Destination[Length] is always set to null.
   
     This function is similar as strncpy_s defined in C11.
   
     If an error is returned, then the Destination is unmodified.
   
     @param  Destination              A pointer to a Null-terminated Ascii string.
     @param  DestMax                  The maximum number of Destination Ascii
                                      char, including terminating null char.
     @param  Source                   A pointer to a Null-terminated Ascii string.
     @param  Length                   The maximum number of Ascii characters to copy.
   
     @retval RETURN_SUCCESS           String is copied.
     @retval RETURN_BUFFER_TOO_SMALL  If DestMax is NOT greater than
                                      MIN(StrLen(Source), Length).
     @retval RETURN_INVALID_PARAMETER If Destination is NULL.
                                      If Source is NULL.
                                      If PcdMaximumAsciiStringLength is not zero,
                                       and DestMax is greater than
                                       PcdMaximumAsciiStringLength.
                                      If DestMax is 0.
     @retval RETURN_ACCESS_DENIED     If Source and Destination overlap.
   **/
   RETURN_STATUS
   EFIAPI
   AsciiStrnCpyS (
     OUT CHAR8        *Destination,
     IN  UINTN        DestMax,
     IN  CONST CHAR8  *Source,
     IN  UINTN        Length
     );
   
   /**
     Appends a copy of the string pointed to by Source (including the terminating
     null char) to the end of the string pointed to by Destination.
   
     This function is similar as strcat_s defined in C11.
   
     If an error is returned, then the Destination is unmodified.
   
     @param  Destination              A pointer to a Null-terminated Ascii string.
     @param  DestMax                  The maximum number of Destination Ascii
                                      char, including terminating null char.
     @param  Source                   A pointer to a Null-terminated Ascii string.
   
     @retval RETURN_SUCCESS           String is appended.
     @retval RETURN_BAD_BUFFER_SIZE   If DestMax is NOT greater than
                                      StrLen(Destination).
     @retval RETURN_BUFFER_TOO_SMALL  If (DestMax - StrLen(Destination)) is NOT
                                      greater than StrLen(Source).
     @retval RETURN_INVALID_PARAMETER If Destination is NULL.
                                      If Source is NULL.
                                      If PcdMaximumAsciiStringLength is not zero,
                                       and DestMax is greater than
                                       PcdMaximumAsciiStringLength.
                                      If DestMax is 0.
     @retval RETURN_ACCESS_DENIED     If Source and Destination overlap.
   **/
   RETURN_STATUS
   EFIAPI
   AsciiStrCatS (
     IN OUT CHAR8        *Destination,
     IN     UINTN        DestMax,
     IN     CONST CHAR8  *Source
     );
   
   /**
     Appends not more than Length successive char from the string pointed to by
     Source to the end of the string pointed to by Destination. If no null char is
     copied from Source, then Destination[StrLen(Destination) + Length] is always
     set to null.
   
     This function is similar as strncat_s defined in C11.
   
     If an error is returned, then the Destination is unmodified.
   
     @param  Destination              A pointer to a Null-terminated Ascii string.
     @param  DestMax                  The maximum number of Destination Ascii
                                      char, including terminating null char.
     @param  Source                   A pointer to a Null-terminated Ascii string.
     @param  Length                   The maximum number of Ascii characters to copy.
   
     @retval RETURN_SUCCESS           String is appended.
     @retval RETURN_BAD_BUFFER_SIZE   If DestMax is NOT greater than
                                      StrLen(Destination).
     @retval RETURN_BUFFER_TOO_SMALL  If (DestMax - StrLen(Destination)) is NOT
                                      greater than MIN(StrLen(Source), Length).
     @retval RETURN_INVALID_PARAMETER If Destination is NULL.
                                      If Source is NULL.
                                      If PcdMaximumAsciiStringLength is not zero,
                                       and DestMax is greater than
                                       PcdMaximumAsciiStringLength.
                                      If DestMax is 0.
     @retval RETURN_ACCESS_DENIED     If Source and Destination overlap.
   **/
   RETURN_STATUS
   EFIAPI
   AsciiStrnCatS (
     IN OUT CHAR8        *Destination,
     IN     UINTN        DestMax,
     IN     CONST CHAR8  *Source,
     IN     UINTN        Length
     );
   
   /**
     Convert a Null-terminated Ascii decimal string to a value of type UINTN.
   
     This function outputs a value of type UINTN by interpreting the contents of
     the Ascii string specified by String as a decimal number. The format of the
     input Ascii string String is:
   
                     [spaces] [decimal digits].
   
     The valid decimal digit character is in the range [0-9]. The function will
     ignore the pad space, which includes spaces or tab characters, before
     [decimal digits]. The running zero in the beginning of [decimal digits] will
     be ignored. Then, the function stops at the first character that is a not a
     valid decimal character or a Null-terminator, whichever one comes first.
   
     If String has no valid decimal digits in the above format, then 0 is stored
     at the location pointed to by Data.
     If the number represented by String exceeds the range defined by UINTN, then
     MAX_UINTN is stored at the location pointed to by Data.
   
     If EndPointer is not NULL, a pointer to the character that stopped the scan
     is stored at the location pointed to by EndPointer. If String has no valid
     decimal digits right after the optional pad spaces, the value of String is
     stored at the location pointed to by EndPointer.
   
     @param  String                   Pointer to a Null-terminated Ascii string.
     @param  EndPointer               Pointer to character that stops scan.
     @param  Data                     Pointer to the converted value.
   
     @retval RETURN_SUCCESS           Value is translated from String.
     @retval RETURN_INVALID_PARAMETER If String is NULL.
                                      If Data is NULL.
                                      If PcdMaximumAsciiStringLength is not zero,
                                      and String contains more than
                                      PcdMaximumAsciiStringLength Ascii
                                      characters, not including the
                                      Null-terminator.
     @retval RETURN_UNSUPPORTED       If the number represented by String exceeds
                                      the range defined by UINTN.
   
   **/
   RETURN_STATUS
   EFIAPI
   AsciiStrDecimalToUintnS (
     IN  CONST CHAR8              *String,
     OUT       CHAR8              **EndPointer,  OPTIONAL
     OUT       UINTN              *Data
     );
   
   /**
     Convert a Null-terminated Ascii decimal string to a value of type UINT64.
   
     This function outputs a value of type UINT64 by interpreting the contents of
     the Ascii string specified by String as a decimal number. The format of the
     input Ascii string String is:
   
                     [spaces] [decimal digits].
   
     The valid decimal digit character is in the range [0-9]. The function will
     ignore the pad space, which includes spaces or tab characters, before
     [decimal digits]. The running zero in the beginning of [decimal digits] will
     be ignored. Then, the function stops at the first character that is a not a
     valid decimal character or a Null-terminator, whichever one comes first.
   
     If String has no valid decimal digits in the above format, then 0 is stored
     at the location pointed to by Data.
     If the number represented by String exceeds the range defined by UINT64, then
     MAX_UINT64 is stored at the location pointed to by Data.
   
     If EndPointer is not NULL, a pointer to the character that stopped the scan
     is stored at the location pointed to by EndPointer. If String has no valid
     decimal digits right after the optional pad spaces, the value of String is
     stored at the location pointed to by EndPointer.
   
     @param  String                   Pointer to a Null-terminated Ascii string.
     @param  EndPointer               Pointer to character that stops scan.
     @param  Data                     Pointer to the converted value.
   
     @retval RETURN_SUCCESS           Value is translated from String.
     @retval RETURN_INVALID_PARAMETER If String is NULL.
                                      If Data is NULL.
                                      If PcdMaximumAsciiStringLength is not zero,
                                      and String contains more than
                                      PcdMaximumAsciiStringLength Ascii
                                      characters, not including the
                                      Null-terminator.
     @retval RETURN_UNSUPPORTED       If the number represented by String exceeds
                                      the range defined by UINT64.
   
   **/
   RETURN_STATUS
   EFIAPI
   AsciiStrDecimalToUint64S (
     IN  CONST CHAR8              *String,
     OUT       CHAR8              **EndPointer,  OPTIONAL
     OUT       UINT64             *Data
     );
   
   /**
     Convert a Null-terminated Ascii hexadecimal string to a value of type UINTN.
   
     This function outputs a value of type UINTN by interpreting the contents of
     the Ascii string specified by String as a hexadecimal number. The format of
     the input Ascii string String is:
   
                     [spaces][zeros][x][hexadecimal digits].
   
     The valid hexadecimal digit character is in the range [0-9], [a-f] and [A-F].
     The prefix "0x" is optional. Both "x" and "X" is allowed in "0x" prefix. If
     "x" appears in the input string, it must be prefixed with at least one 0. The
     function will ignore the pad space, which includes spaces or tab characters,
     before [zeros], [x] or [hexadecimal digits]. The running zero before [x] or
     [hexadecimal digits] will be ignored. Then, the decoding starts after [x] or
     the first valid hexadecimal digit. Then, the function stops at the first
     character that is a not a valid hexadecimal character or Null-terminator,
     whichever on comes first.
   
     If String has no valid hexadecimal digits in the above format, then 0 is
     stored at the location pointed to by Data.
     If the number represented by String exceeds the range defined by UINTN, then
     MAX_UINTN is stored at the location pointed to by Data.
   
     If EndPointer is not NULL, a pointer to the character that stopped the scan
     is stored at the location pointed to by EndPointer. If String has no valid
     hexadecimal digits right after the optional pad spaces, the value of String
     is stored at the location pointed to by EndPointer.
   
     @param  String                   Pointer to a Null-terminated Ascii string.
     @param  EndPointer               Pointer to character that stops scan.
     @param  Data                     Pointer to the converted value.
   
     @retval RETURN_SUCCESS           Value is translated from String.
     @retval RETURN_INVALID_PARAMETER If String is NULL.
                                      If Data is NULL.
                                      If PcdMaximumAsciiStringLength is not zero,
                                      and String contains more than
                                      PcdMaximumAsciiStringLength Ascii
                                      characters, not including the
                                      Null-terminator.
     @retval RETURN_UNSUPPORTED       If the number represented by String exceeds
                                      the range defined by UINTN.
   
   **/
   RETURN_STATUS
   EFIAPI
   AsciiStrHexToUintnS (
     IN  CONST CHAR8              *String,
     OUT       CHAR8              **EndPointer,  OPTIONAL
     OUT       UINTN              *Data
     );
   
   /**
     Convert a Null-terminated Ascii hexadecimal string to a value of type UINT64.
   
     This function outputs a value of type UINT64 by interpreting the contents of
     the Ascii string specified by String as a hexadecimal number. The format of
     the input Ascii string String is:
   
                     [spaces][zeros][x][hexadecimal digits].
   
     The valid hexadecimal digit character is in the range [0-9], [a-f] and [A-F].
     The prefix "0x" is optional. Both "x" and "X" is allowed in "0x" prefix. If
     "x" appears in the input string, it must be prefixed with at least one 0. The
     function will ignore the pad space, which includes spaces or tab characters,
     before [zeros], [x] or [hexadecimal digits]. The running zero before [x] or
     [hexadecimal digits] will be ignored. Then, the decoding starts after [x] or
     the first valid hexadecimal digit. Then, the function stops at the first
     character that is a not a valid hexadecimal character or Null-terminator,
     whichever on comes first.
   
     If String has no valid hexadecimal digits in the above format, then 0 is
     stored at the location pointed to by Data.
     If the number represented by String exceeds the range defined by UINT64, then
     MAX_UINT64 is stored at the location pointed to by Data.
   
     If EndPointer is not NULL, a pointer to the character that stopped the scan
     is stored at the location pointed to by EndPointer. If String has no valid
     hexadecimal digits right after the optional pad spaces, the value of String
     is stored at the location pointed to by EndPointer.
   
     @param  String                   Pointer to a Null-terminated Ascii string.
     @param  EndPointer               Pointer to character that stops scan.
     @param  Data                     Pointer to the converted value.
   
     @retval RETURN_SUCCESS           Value is translated from String.
     @retval RETURN_INVALID_PARAMETER If String is NULL.
                                      If Data is NULL.
                                      If PcdMaximumAsciiStringLength is not zero,
                                      and String contains more than
                                      PcdMaximumAsciiStringLength Ascii
                                      characters, not including the
                                      Null-terminator.
     @retval RETURN_UNSUPPORTED       If the number represented by String exceeds
                                      the range defined by UINT64.
   
   **/
   RETURN_STATUS
   EFIAPI
   AsciiStrHexToUint64S (
     IN  CONST CHAR8              *String,
     OUT       CHAR8              **EndPointer,  OPTIONAL
     OUT       UINT64             *Data
     );
   
   
   #ifndef DISABLE_NEW_DEPRECATED_INTERFACES
   
   /**
     [ATTENTION] This function is deprecated for security reason.
   
     Copies one Null-terminated Unicode string to another Null-terminated Unicode
     string and returns the new Unicode string.
   
     This function copies the contents of the Unicode string Source to the Unicode
     string Destination, and returns Destination. If Source and Destination
     overlap, then the results are undefined.
   
     If Destination is NULL, then ASSERT().
     If Destination is not aligned on a 16-bit boundary, then ASSERT().
     If Source is NULL, then ASSERT().
     If Source is not aligned on a 16-bit boundary, then ASSERT().
     If Source and Destination overlap, then ASSERT().
     If PcdMaximumUnicodeStringLength is not zero, and Source contains more than
     PcdMaximumUnicodeStringLength Unicode characters not including the
     Null-terminator, then ASSERT().
   
     @param  Destination The pointer to a Null-terminated Unicode string.
     @param  Source      The pointer to a Null-terminated Unicode string.
   
     @return Destination.
   
   **/
   CHAR16 *
   EFIAPI
   StrCpy (
     OUT     CHAR16                    *Destination,
     IN      CONST CHAR16              *Source
     );
   
   
  /**
    [ATTENTION] This function is deprecated for security reason.
  
    Copies up to a specified length from one Null-terminated Unicode string to
    another Null-terminated Unicode string and returns the new Unicode string.
  
    This function copies the contents of the Unicode string Source to the Unicode
    string Destination, and returns Destination. At most, Length Unicode
    characters are copied from Source to Destination. If Length is 0, then
    Destination is returned unmodified. If Length is greater that the number of
    Unicode characters in Source, then Destination is padded with Null Unicode
    characters. If Source and Destination overlap, then the results are
    undefined.
  
    If Length > 0 and Destination is NULL, then ASSERT().
    If Length > 0 and Destination is not aligned on a 16-bit boundary, then ASSERT().
    If Length > 0 and Source is NULL, then ASSERT().
    If Length > 0 and Source is not aligned on a 16-bit boundary, then ASSERT().
    If Source and Destination overlap, then ASSERT().
    If PcdMaximumUnicodeStringLength is not zero, and Length is greater than
    PcdMaximumUnicodeStringLength, then ASSERT().
    If PcdMaximumUnicodeStringLength is not zero, and Source contains more than
    PcdMaximumUnicodeStringLength Unicode characters, not including the Null-terminator,
    then ASSERT().
  
    @param  Destination The pointer to a Null-terminated Unicode string.
    @param  Source      The pointer to a Null-terminated Unicode string.
    @param  Length      The maximum number of Unicode characters to copy.
  
    @return Destination.
  
  **/
  CHAR16 *
  EFIAPI
  StrnCpy (
    OUT     CHAR16                    *Destination,
    IN      CONST CHAR16              *Source,
    IN      UINTN                     Length
    );
  #endif // !defined (DISABLE_NEW_DEPRECATED_INTERFACES)
  
  /**
    Returns the length of a Null-terminated Unicode string.
  
    This function returns the number of Unicode characters in the Null-terminated
    Unicode string specified by String.
  
    If String is NULL, then ASSERT().
    If String is not aligned on a 16-bit boundary, then ASSERT().
    If PcdMaximumUnicodeStringLength is not zero, and String contains more than
    PcdMaximumUnicodeStringLength Unicode characters not including the
    Null-terminator, then ASSERT().
  
    @param  String  Pointer to a Null-terminated Unicode string.
  
    @return The length of String.
  
  **/
  UINTN
  EFIAPI
  StrLen (
    IN      CONST CHAR16              *String
    );
  
  
  /**
    Returns the size of a Null-terminated Unicode string in bytes, including the
    Null terminator.
  
    This function returns the size, in bytes, of the Null-terminated Unicode string
    specified by String.
  
    If String is NULL, then ASSERT().
    If String is not aligned on a 16-bit boundary, then ASSERT().
    If PcdMaximumUnicodeStringLength is not zero, and String contains more than
    PcdMaximumUnicodeStringLength Unicode characters not including the
    Null-terminator, then ASSERT().
  
    @param  String  The pointer to a Null-terminated Unicode string.
  
    @return The size of String.
  
  **/
  UINTN
  EFIAPI
  StrSize (
    IN      CONST CHAR16              *String
    );
  
  
  /**
    Compares two Null-terminated Unicode strings, and returns the difference
    between the first mismatched Unicode characters.
  
    This function compares the Null-terminated Unicode string FirstString to the
    Null-terminated Unicode string SecondString. If FirstString is identical to
    SecondString, then 0 is returned. Otherwise, the value returned is the first
    mismatched Unicode character in SecondString subtracted from the first
    mismatched Unicode character in FirstString.
  
    If FirstString is NULL, then ASSERT().
    If FirstString is not aligned on a 16-bit boundary, then ASSERT().
    If SecondString is NULL, then ASSERT().
    If SecondString is not aligned on a 16-bit boundary, then ASSERT().
    If PcdMaximumUnicodeStringLength is not zero, and FirstString contains more
    than PcdMaximumUnicodeStringLength Unicode characters not including the
    Null-terminator, then ASSERT().
    If PcdMaximumUnicodeStringLength is not zero, and SecondString contains more
    than PcdMaximumUnicodeStringLength Unicode characters, not including the
    Null-terminator, then ASSERT().
  
    @param  FirstString   The pointer to a Null-terminated Unicode string.
    @param  SecondString  The pointer to a Null-terminated Unicode string.
  
    @retval 0      FirstString is identical to SecondString.
    @return others FirstString is not identical to SecondString.
  
  **/
  INTN
  EFIAPI
  StrCmp (
    IN      CONST CHAR16              *FirstString,
    IN      CONST CHAR16              *SecondString
    );
  
  
  /**
    Compares up to a specified length the contents of two Null-terminated Unicode strings,
    and returns the difference between the first mismatched Unicode characters.
  
    This function compares the Null-terminated Unicode string FirstString to the
    Null-terminated Unicode string SecondString. At most, Length Unicode
    characters will be compared. If Length is 0, then 0 is returned. If
    FirstString is identical to SecondString, then 0 is returned. Otherwise, the
    value returned is the first mismatched Unicode character in SecondString
    subtracted from the first mismatched Unicode character in FirstString.
  
    If Length > 0 and FirstString is NULL, then ASSERT().
    If Length > 0 and FirstString is not aligned on a 16-bit boundary, then ASSERT().
    If Length > 0 and SecondString is NULL, then ASSERT().
    If Length > 0 and SecondString is not aligned on a 16-bit boundary, then ASSERT().
    If PcdMaximumUnicodeStringLength is not zero, and Length is greater than
    PcdMaximumUnicodeStringLength, then ASSERT().
    If PcdMaximumUnicodeStringLength is not zero, and FirstString contains more than
    PcdMaximumUnicodeStringLength Unicode characters, not including the Null-terminator,
    then ASSERT().
    If PcdMaximumUnicodeStringLength is not zero, and SecondString contains more than
    PcdMaximumUnicodeStringLength Unicode characters, not including the Null-terminator,
    then ASSERT().
  
    @param  FirstString   The pointer to a Null-terminated Unicode string.
    @param  SecondString  The pointer to a Null-terminated Unicode string.
    @param  Length        The maximum number of Unicode characters to compare.
  
    @retval 0      FirstString is identical to SecondString.
    @return others FirstString is not identical to SecondString.
  
  **/
  INTN
  EFIAPI
  StrnCmp (
    IN      CONST CHAR16              *FirstString,
    IN      CONST CHAR16              *SecondString,
    IN      UINTN                     Length
    );
  
  
  #ifndef DISABLE_NEW_DEPRECATED_INTERFACES
  
  /**
    [ATTENTION] This function is deprecated for security reason.
  
    Concatenates one Null-terminated Unicode string to another Null-terminated
    Unicode string, and returns the concatenated Unicode string.
  
    This function concatenates two Null-terminated Unicode strings. The contents
    of Null-terminated Unicode string Source are concatenated to the end of
    Null-terminated Unicode string Destination. The Null-terminated concatenated
    Unicode String is returned. If Source and Destination overlap, then the
    results are undefined.
  
    If Destination is NULL, then ASSERT().
    If Destination is not aligned on a 16-bit boundary, then ASSERT().
    If Source is NULL, then ASSERT().
    If Source is not aligned on a 16-bit boundary, then ASSERT().
    If Source and Destination overlap, then ASSERT().
    If PcdMaximumUnicodeStringLength is not zero, and Destination contains more
    than PcdMaximumUnicodeStringLength Unicode characters, not including the
    Null-terminator, then ASSERT().
    If PcdMaximumUnicodeStringLength is not zero, and Source contains more than
    PcdMaximumUnicodeStringLength Unicode characters, not including the
    Null-terminator, then ASSERT().
    If PcdMaximumUnicodeStringLength is not zero, and concatenating Destination
    and Source results in a Unicode string with more than
    PcdMaximumUnicodeStringLength Unicode characters, not including the
    Null-terminator, then ASSERT().
  
    @param  Destination The pointer to a Null-terminated Unicode string.
    @param  Source      The pointer to a Null-terminated Unicode string.
  
    @return Destination.
  
  **/
  CHAR16 *
  EFIAPI
  StrCat (
    IN OUT  CHAR16                    *Destination,
    IN      CONST CHAR16              *Source
    );
  
  
  /**
    [ATTENTION] This function is deprecated for security reason.
  
    Concatenates up to a specified length one Null-terminated Unicode to the end
    of another Null-terminated Unicode string, and returns the concatenated
    Unicode string.
  
    This function concatenates two Null-terminated Unicode strings. The contents
    of Null-terminated Unicode string Source are concatenated to the end of
    Null-terminated Unicode string Destination, and Destination is returned. At
    most, Length Unicode characters are concatenated from Source to the end of
    Destination, and Destination is always Null-terminated. If Length is 0, then
    Destination is returned unmodified. If Source and Destination overlap, then
    the results are undefined.
  
    If Destination is NULL, then ASSERT().
    If Length > 0 and Destination is not aligned on a 16-bit boundary, then ASSERT().
    If Length > 0 and Source is NULL, then ASSERT().
    If Length > 0 and Source is not aligned on a 16-bit boundary, then ASSERT().
    If Source and Destination overlap, then ASSERT().
    If PcdMaximumUnicodeStringLength is not zero, and Length is greater than
    PcdMaximumUnicodeStringLength, then ASSERT().
    If PcdMaximumUnicodeStringLength is not zero, and Destination contains more
    than PcdMaximumUnicodeStringLength Unicode characters, not including the
    Null-terminator, then ASSERT().
    If PcdMaximumUnicodeStringLength is not zero, and Source contains more than
    PcdMaximumUnicodeStringLength Unicode characters, not including the
    Null-terminator, then ASSERT().
    If PcdMaximumUnicodeStringLength is not zero, and concatenating Destination
    and Source results in a Unicode string with more than PcdMaximumUnicodeStringLength
    Unicode characters, not including the Null-terminator, then ASSERT().
  
    @param  Destination The pointer to a Null-terminated Unicode string.
    @param  Source      The pointer to a Null-terminated Unicode string.
    @param  Length      The maximum number of Unicode characters to concatenate from
                        Source.
  
    @return Destination.
  
  **/
  CHAR16 *
  EFIAPI
  StrnCat (
    IN OUT  CHAR16                    *Destination,
    IN      CONST CHAR16              *Source,
    IN      UINTN                     Length
    );
  #endif // !defined (DISABLE_NEW_DEPRECATED_INTERFACES)
  
  /**
    Returns the first occurrence of a Null-terminated Unicode sub-string
    in a Null-terminated Unicode string.
  
    This function scans the contents of the Null-terminated Unicode string
    specified by String and returns the first occurrence of SearchString.
    If SearchString is not found in String, then NULL is returned.  If
    the length of SearchString is zero, then String is returned.
  
    If String is NULL, then ASSERT().
    If String is not aligned on a 16-bit boundary, then ASSERT().
    If SearchString is NULL, then ASSERT().
    If SearchString is not aligned on a 16-bit boundary, then ASSERT().
  
    If PcdMaximumUnicodeStringLength is not zero, and SearchString
    or String contains more than PcdMaximumUnicodeStringLength Unicode
    characters, not including the Null-terminator, then ASSERT().
  
    @param  String          The pointer to a Null-terminated Unicode string.
    @param  SearchString    The pointer to a Null-terminated Unicode string to search for.
  
    @retval NULL            If the SearchString does not appear in String.
    @return others          If there is a match.
  
  **/
  CHAR16 *
  EFIAPI
  StrStr (
    IN      CONST CHAR16              *String,
    IN      CONST CHAR16              *SearchString
    );
  
  /**
    Convert a Null-terminated Unicode decimal string to a value of
    type UINTN.
  
    This function returns a value of type UINTN by interpreting the contents
    of the Unicode string specified by String as a decimal number. The format
    of the input Unicode string String is:
  
                    [spaces] [decimal digits].
  
    The valid decimal digit character is in the range [0-9]. The
    function will ignore the pad space, which includes spaces or
    tab characters, before [decimal digits]. The running zero in the
    beginning of [decimal digits] will be ignored. Then, the function
    stops at the first character that is a not a valid decimal character
    or a Null-terminator, whichever one comes first.
  
    If String is NULL, then ASSERT().
    If String is not aligned in a 16-bit boundary, then ASSERT().
    If String has only pad spaces, then 0 is returned.
    If String has no pad spaces or valid decimal digits,
    then 0 is returned.
    If the number represented by String overflows according
    to the range defined by UINTN, then MAX_UINTN is returned.
  
    If PcdMaximumUnicodeStringLength is not zero, and String contains
    more than PcdMaximumUnicodeStringLength Unicode characters not including
    the Null-terminator, then ASSERT().
  
    @param  String      The pointer to a Null-terminated Unicode string.
  
    @retval Value translated from String.
  
  **/
  UINTN
  EFIAPI
  StrDecimalToUintn (
    IN      CONST CHAR16              *String
    );
  
  /**
    Convert a Null-terminated Unicode decimal string to a value of
    type UINT64.
  
    This function returns a value of type UINT64 by interpreting the contents
    of the Unicode string specified by String as a decimal number. The format
    of the input Unicode string String is:
  
                    [spaces] [decimal digits].
  
    The valid decimal digit character is in the range [0-9]. The
    function will ignore the pad space, which includes spaces or
    tab characters, before [decimal digits]. The running zero in the
    beginning of [decimal digits] will be ignored. Then, the function
    stops at the first character that is a not a valid decimal character
    or a Null-terminator, whichever one comes first.
  
    If String is NULL, then ASSERT().
    If String is not aligned in a 16-bit boundary, then ASSERT().
    If String has only pad spaces, then 0 is returned.
    If String has no pad spaces or valid decimal digits,
    then 0 is returned.
    If the number represented by String overflows according
    to the range defined by UINT64, then MAX_UINT64 is returned.
  
    If PcdMaximumUnicodeStringLength is not zero, and String contains
    more than PcdMaximumUnicodeStringLength Unicode characters not including
    the Null-terminator, then ASSERT().
  
    @param  String          The pointer to a Null-terminated Unicode string.
  
    @retval Value translated from String.
  
  **/
  UINT64
  EFIAPI
  StrDecimalToUint64 (
    IN      CONST CHAR16              *String
    );
  
  
  /**
    Convert a Null-terminated Unicode hexadecimal string to a value of type UINTN.
  
    This function returns a value of type UINTN by interpreting the contents
    of the Unicode string specified by String as a hexadecimal number.
    The format of the input Unicode string String is:
  
                    [spaces][zeros][x][hexadecimal digits].
  
    The valid hexadecimal digit character is in the range [0-9], [a-f] and [A-F].
    The prefix "0x" is optional. Both "x" and "X" is allowed in "0x" prefix.
    If "x" appears in the input string, it must be prefixed with at least one 0.
    The function will ignore the pad space, which includes spaces or tab characters,
    before [zeros], [x] or [hexadecimal digit]. The running zero before [x] or
    [hexadecimal digit] will be ignored. Then, the decoding starts after [x] or the
    first valid hexadecimal digit. Then, the function stops at the first character
    that is a not a valid hexadecimal character or NULL, whichever one comes first.
  
    If String is NULL, then ASSERT().
    If String is not aligned in a 16-bit boundary, then ASSERT().
    If String has only pad spaces, then zero is returned.
    If String has no leading pad spaces, leading zeros or valid hexadecimal digits,
    then zero is returned.
    If the number represented by String overflows according to the range defined by
    UINTN, then MAX_UINTN is returned.
  
    If PcdMaximumUnicodeStringLength is not zero, and String contains more than
    PcdMaximumUnicodeStringLength Unicode characters not including the Null-terminator,
    then ASSERT().
  
    @param  String          The pointer to a Null-terminated Unicode string.
  
    @retval Value translated from String.
  
  **/
  UINTN
  EFIAPI
  StrHexToUintn (
    IN      CONST CHAR16              *String
    );
  
  
  /**
    Convert a Null-terminated Unicode hexadecimal string to a value of type UINT64.
  
    This function returns a value of type UINT64 by interpreting the contents
    of the Unicode string specified by String as a hexadecimal number.
    The format of the input Unicode string String is
  
                    [spaces][zeros][x][hexadecimal digits].
  
    The valid hexadecimal digit character is in the range [0-9], [a-f] and [A-F].
    The prefix "0x" is optional. Both "x" and "X" is allowed in "0x" prefix.
    If "x" appears in the input string, it must be prefixed with at least one 0.
    The function will ignore the pad space, which includes spaces or tab characters,
    before [zeros], [x] or [hexadecimal digit]. The running zero before [x] or
    [hexadecimal digit] will be ignored. Then, the decoding starts after [x] or the
    first valid hexadecimal digit. Then, the function stops at the first character that is
    a not a valid hexadecimal character or NULL, whichever one comes first.
  
    If String is NULL, then ASSERT().
    If String is not aligned in a 16-bit boundary, then ASSERT().
    If String has only pad spaces, then zero is returned.
    If String has no leading pad spaces, leading zeros or valid hexadecimal digits,
    then zero is returned.
    If the number represented by String overflows according to the range defined by
    UINT64, then MAX_UINT64 is returned.
  
    If PcdMaximumUnicodeStringLength is not zero, and String contains more than
    PcdMaximumUnicodeStringLength Unicode characters not including the Null-terminator,
    then ASSERT().
  
    @param  String          The pointer to a Null-terminated Unicode string.
  
    @retval Value translated from String.
  
  **/
  UINT64
  EFIAPI
  StrHexToUint64 (
    IN      CONST CHAR16             *String
    );
  
  /**
    Convert a Null-terminated Unicode string to IPv6 address and prefix length.
  
    This function outputs a value of type IPv6_ADDRESS and may output a value
    of type UINT8 by interpreting the contents of the Unicode string specified
    by String. The format of the input Unicode string String is as follows:
  
                    X:X:X:X:X:X:X:X[/P]
  
    X contains one to four hexadecimal digit characters in the range [0-9], [a-f] and
    [A-F]. X is converted to a value of type UINT16, whose low byte is stored in low
    memory address and high byte is stored in high memory address. P contains decimal
    digit characters in the range [0-9]. The running zero in the beginning of P will
    be ignored. /P is optional.
  
    When /P is not in the String, the function stops at the first character that is
    not a valid hexadecimal digit character after eight X's are converted.
  
    When /P is in the String, the function stops at the first character that is not
    a valid decimal digit character after P is converted.
  
    "::" can be used to compress one or more groups of X when X contains only 0.
    The "::" can only appear once in the String.
  
    If String is not aligned in a 16-bit boundary, then ASSERT().
  
    If EndPointer is not NULL and Address is translated from String, a pointer
    to the character that stopped the scan is stored at the location pointed to
    by EndPointer.
  
    @param  String                   Pointer to a Null-terminated Unicode string.
    @param  EndPointer               Pointer to character that stops scan.
    @param  Address                  Pointer to the converted IPv6 address.
    @param  PrefixLength             Pointer to the converted IPv6 address prefix
                                     length. MAX_UINT8 is returned when /P is
                                     not in the String.
  
    @retval RETURN_SUCCESS           Address is translated from String.
    @retval RETURN_INVALID_PARAMETER If String is NULL.
                                     If Data is NULL.
    @retval RETURN_UNSUPPORTED       If X contains more than four hexadecimal
                                      digit characters.
                                     If String contains "::" and number of X
                                      is not less than 8.
                                     If P starts with character that is not a
                                      valid decimal digit character.
                                     If the decimal number converted from P
                                      exceeds 128.
  
  **/
  RETURN_STATUS
  EFIAPI
  StrToIpv6Address (
    IN  CONST CHAR16       *String,
    OUT CHAR16             **EndPointer, OPTIONAL
    OUT IPv6_ADDRESS       *Address,
    OUT UINT8              *PrefixLength OPTIONAL
    );
  
  /**
    Convert a Null-terminated Unicode string to IPv4 address and prefix length.
  
    This function outputs a value of type IPv4_ADDRESS and may output a value
    of type UINT8 by interpreting the contents of the Unicode string specified
    by String. The format of the input Unicode string String is as follows:
  
                    D.D.D.D[/P]
  
    D and P are decimal digit characters in the range [0-9]. The running zero in
    the beginning of D and P will be ignored. /P is optional.
  
    When /P is not in the String, the function stops at the first character that is
    not a valid decimal digit character after four D's are converted.
  
    When /P is in the String, the function stops at the first character that is not
    a valid decimal digit character after P is converted.
  
    If String is not aligned in a 16-bit boundary, then ASSERT().
  
    If EndPointer is not NULL and Address is translated from String, a pointer
    to the character that stopped the scan is stored at the location pointed to
    by EndPointer.
  
    @param  String                   Pointer to a Null-terminated Unicode string.
    @param  EndPointer               Pointer to character that stops scan.
    @param  Address                  Pointer to the converted IPv4 address.
    @param  PrefixLength             Pointer to the converted IPv4 address prefix
                                     length. MAX_UINT8 is returned when /P is
                                     not in the String.
  
    @retval RETURN_SUCCESS           Address is translated from String.
    @retval RETURN_INVALID_PARAMETER If String is NULL.
                                     If Data is NULL.
    @retval RETURN_UNSUPPORTED       If String is not in the correct format.
                                     If any decimal number converted from D
                                      exceeds 255.
                                     If the decimal number converted from P
                                      exceeds 32.
  
  **/
  RETURN_STATUS
  EFIAPI
  StrToIpv4Address (
    IN  CONST CHAR16       *String,
    OUT CHAR16             **EndPointer, OPTIONAL
    OUT IPv4_ADDRESS       *Address,
    OUT UINT8              *PrefixLength OPTIONAL
    );
  
  #define GUID_STRING_LENGTH  36
  
  /**
    Convert a Null-terminated Unicode GUID string to a value of type
    EFI_GUID.
  
    This function outputs a GUID value by interpreting the contents of
    the Unicode string specified by String. The format of the input
    Unicode string String consists of 36 characters, as follows:
  
                    aabbccdd-eeff-gghh-iijj-kkllmmnnoopp
  
    The pairs aa - pp are two characters in the range [0-9], [a-f] and
    [A-F], with each pair representing a single byte hexadecimal value.
  
    The mapping between String and the EFI_GUID structure is as follows:
                    aa          Data1[24:31]
                    bb          Data1[16:23]
                    cc          Data1[8:15]
                    dd          Data1[0:7]
                    ee          Data2[8:15]
                    ff          Data2[0:7]
                    gg          Data3[8:15]
                    hh          Data3[0:7]
                    ii          Data4[0:7]
                    jj          Data4[8:15]
                    kk          Data4[16:23]
                    ll          Data4[24:31]
                    mm          Data4[32:39]
                    nn          Data4[40:47]
                    oo          Data4[48:55]
                    pp          Data4[56:63]
  
    If String is not aligned in a 16-bit boundary, then ASSERT().
  
    @param  String                   Pointer to a Null-terminated Unicode string.
    @param  Guid                     Pointer to the converted GUID.
  
    @retval RETURN_SUCCESS           Guid is translated from String.
    @retval RETURN_INVALID_PARAMETER If String is NULL.
                                     If Data is NULL.
    @retval RETURN_UNSUPPORTED       If String is not as the above format.
  
  **/
  RETURN_STATUS
  EFIAPI
  StrToGuid (
    IN  CONST CHAR16       *String,
    OUT GUID               *Guid
    );
  
  /**
    Convert a Null-terminated Unicode hexadecimal string to a byte array.
  
    This function outputs a byte array by interpreting the contents of
    the Unicode string specified by String in hexadecimal format. The format of
    the input Unicode string String is:
  
                    [XX]*
  
    X is a hexadecimal digit character in the range [0-9], [a-f] and [A-F].
    The function decodes every two hexadecimal digit characters as one byte. The
    decoding stops after Length of characters and outputs Buffer containing
    (Length / 2) bytes.
  
    If String is not aligned in a 16-bit boundary, then ASSERT().
  
    @param  String                   Pointer to a Null-terminated Unicode string.
    @param  Length                   The number of Unicode characters to decode.
    @param  Buffer                   Pointer to the converted bytes array.
    @param  MaxBufferSize            The maximum size of Buffer.
  
    @retval RETURN_SUCCESS           Buffer is translated from String.
    @retval RETURN_INVALID_PARAMETER If String is NULL.
                                     If Data is NULL.
                                     If Length is not multiple of 2.
                                     If PcdMaximumUnicodeStringLength is not zero,
                                      and Length is greater than
                                      PcdMaximumUnicodeStringLength.
    @retval RETURN_UNSUPPORTED       If Length of characters from String contain
                                      a character that is not valid hexadecimal
                                      digit characters, or a Null-terminator.
    @retval RETURN_BUFFER_TOO_SMALL  If MaxBufferSize is less than (Length / 2).
  **/
  RETURN_STATUS
  EFIAPI
  StrHexToBytes (
    IN  CONST CHAR16       *String,
    IN  UINTN              Length,
    OUT UINT8              *Buffer,
    IN  UINTN              MaxBufferSize
    );
  
  #ifndef DISABLE_NEW_DEPRECATED_INTERFACES
  
  /**
    [ATTENTION] This function is deprecated for security reason.
  
    Convert a Null-terminated Unicode string to a Null-terminated
    ASCII string and returns the ASCII string.
  
    This function converts the content of the Unicode string Source
    to the ASCII string Destination by copying the lower 8 bits of
    each Unicode character. It returns Destination.
  
    The caller is responsible to make sure Destination points to a buffer with size
    equal or greater than ((StrLen (Source) + 1) * sizeof (CHAR8)) in bytes.
  
    If any Unicode characters in Source contain non-zero value in
    the upper 8 bits, then ASSERT().
  
    If Destination is NULL, then ASSERT().
    If Source is NULL, then ASSERT().
    If Source is not aligned on a 16-bit boundary, then ASSERT().
    If Source and Destination overlap, then ASSERT().
  
    If PcdMaximumUnicodeStringLength is not zero, and Source contains
    more than PcdMaximumUnicodeStringLength Unicode characters not including
    the Null-terminator, then ASSERT().
  
    If PcdMaximumAsciiStringLength is not zero, and Source contains more
    than PcdMaximumAsciiStringLength Unicode characters not including the
    Null-terminator, then ASSERT().
  
    @param  Source        The pointer to a Null-terminated Unicode string.
    @param  Destination   The pointer to a Null-terminated ASCII string.
  
    @return Destination.
  
  **/
  CHAR8 *
  EFIAPI
  UnicodeStrToAsciiStr (
    IN      CONST CHAR16              *Source,
    OUT     CHAR8                     *Destination
    );
  
  #endif // !defined (DISABLE_NEW_DEPRECATED_INTERFACES)
  
  /**
    Convert a Null-terminated Unicode string to a Null-terminated
    ASCII string.
  
    This function is similar to AsciiStrCpyS.
  
    This function converts the content of the Unicode string Source
    to the ASCII string Destination by copying the lower 8 bits of
    each Unicode character. The function terminates the ASCII string
    Destination by appending a Null-terminator character at the end.
  
    The caller is responsible to make sure Destination points to a buffer with size
    equal or greater than ((StrLen (Source) + 1) * sizeof (CHAR8)) in bytes.
  
    If any Unicode characters in Source contain non-zero value in
    the upper 8 bits, then ASSERT().
  
    If Source is not aligned on a 16-bit boundary, then ASSERT().
  
    If an error is returned, then the Destination is unmodified.
  
    @param  Source        The pointer to a Null-terminated Unicode string.
    @param  Destination   The pointer to a Null-terminated ASCII string.
    @param  DestMax       The maximum number of Destination Ascii
                          char, including terminating null char.
  
    @retval RETURN_SUCCESS           String is converted.
    @retval RETURN_BUFFER_TOO_SMALL  If DestMax is NOT greater than StrLen(Source).
    @retval RETURN_INVALID_PARAMETER If Destination is NULL.
                                     If Source is NULL.
                                     If PcdMaximumAsciiStringLength is not zero,
                                      and DestMax is greater than
                                      PcdMaximumAsciiStringLength.
                                     If PcdMaximumUnicodeStringLength is not zero,
                                      and DestMax is greater than
                                      PcdMaximumUnicodeStringLength.
                                     If DestMax is 0.
    @retval RETURN_ACCESS_DENIED     If Source and Destination overlap.
  
  **/
  RETURN_STATUS
  EFIAPI
  UnicodeStrToAsciiStrS (
    IN      CONST CHAR16              *Source,
    OUT     CHAR8                     *Destination,
    IN      UINTN                     DestMax
    );
  
  /**
    Convert not more than Length successive characters from a Null-terminated
    Unicode string to a Null-terminated Ascii string. If no null char is copied
    from Source, then Destination[Length] is always set to null.
  
    This function converts not more than Length successive characters from the
    Unicode string Source to the Ascii string Destination by copying the lower 8
    bits of each Unicode character. The function terminates the Ascii string
    Destination by appending a Null-terminator character at the end.
  
    The caller is responsible to make sure Destination points to a buffer with size
    equal or greater than ((StrLen (Source) + 1) * sizeof (CHAR8)) in bytes.
  
    If any Unicode characters in Source contain non-zero value in the upper 8
    bits, then ASSERT().
    If Source is not aligned on a 16-bit boundary, then ASSERT().
  
    If an error is returned, then the Destination is unmodified.
  
    @param  Source             The pointer to a Null-terminated Unicode string.
    @param  Length             The maximum number of Unicode characters to
                               convert.
    @param  Destination        The pointer to a Null-terminated Ascii string.
    @param  DestMax            The maximum number of Destination Ascii
                               char, including terminating null char.
    @param  DestinationLength  The number of Unicode characters converted.
  
    @retval RETURN_SUCCESS            String is converted.
    @retval RETURN_INVALID_PARAMETER  If Destination is NULL.
                                      If Source is NULL.
                                      If DestinationLength is NULL.
                                      If PcdMaximumAsciiStringLength is not zero,
                                      and Length or DestMax is greater than
                                      PcdMaximumAsciiStringLength.
                                      If PcdMaximumUnicodeStringLength is not
                                      zero, and Length or DestMax is greater than
                                      PcdMaximumUnicodeStringLength.
                                      If DestMax is 0.
    @retval RETURN_BUFFER_TOO_SMALL   If DestMax is NOT greater than
                                      MIN(StrLen(Source), Length).
    @retval RETURN_ACCESS_DENIED      If Source and Destination overlap.
  
  **/
  RETURN_STATUS
  EFIAPI
  UnicodeStrnToAsciiStrS (
    IN      CONST CHAR16              *Source,
    IN      UINTN                     Length,
    OUT     CHAR8                     *Destination,
    IN      UINTN                     DestMax,
    OUT     UINTN                     *DestinationLength
    );
  
  #ifndef DISABLE_NEW_DEPRECATED_INTERFACES
  
  /**
    [ATTENTION] This function is deprecated for security reason.
  
    Copies one Null-terminated ASCII string to another Null-terminated ASCII
    string and returns the new ASCII string.
  
    This function copies the contents of the ASCII string Source to the ASCII
    string Destination, and returns Destination. If Source and Destination
    overlap, then the results are undefined.
  
    If Destination is NULL, then ASSERT().
    If Source is NULL, then ASSERT().
    If Source and Destination overlap, then ASSERT().
    If PcdMaximumAsciiStringLength is not zero and Source contains more than
    PcdMaximumAsciiStringLength ASCII characters not including the Null-terminator,
    then ASSERT().
  
    @param  Destination The pointer to a Null-terminated ASCII string.
    @param  Source      The pointer to a Null-terminated ASCII string.
  
    @return Destination
  
  **/
  CHAR8 *
  EFIAPI
  AsciiStrCpy (
    OUT     CHAR8                     *Destination,
    IN      CONST CHAR8               *Source
    );
  
  
  /**
    [ATTENTION] This function is deprecated for security reason.
  
    Copies up to a specified length one Null-terminated ASCII string to another
    Null-terminated ASCII string and returns the new ASCII string.
  
    This function copies the contents of the ASCII string Source to the ASCII
    string Destination, and returns Destination. At most, Length ASCII characters
    are copied from Source to Destination. If Length is 0, then Destination is
    returned unmodified. If Length is greater that the number of ASCII characters
    in Source, then Destination is padded with Null ASCII characters. If Source
    and Destination overlap, then the results are undefined.
  
    If Destination is NULL, then ASSERT().
    If Source is NULL, then ASSERT().
    If Source and Destination overlap, then ASSERT().
    If PcdMaximumAsciiStringLength is not zero, and Length is greater than
    PcdMaximumAsciiStringLength, then ASSERT().
    If PcdMaximumAsciiStringLength is not zero, and Source contains more than
    PcdMaximumAsciiStringLength ASCII characters, not including the Null-terminator,
    then ASSERT().
  
    @param  Destination The pointer to a Null-terminated ASCII string.
    @param  Source      The pointer to a Null-terminated ASCII string.
    @param  Length      The maximum number of ASCII characters to copy.
  
    @return Destination
  
  **/
  CHAR8 *
  EFIAPI
  AsciiStrnCpy (
    OUT     CHAR8                     *Destination,
    IN      CONST CHAR8               *Source,
    IN      UINTN                     Length
    );
  #endif // !defined (DISABLE_NEW_DEPRECATED_INTERFACES)
  
  /**
    Returns the length of a Null-terminated ASCII string.
  
    This function returns the number of ASCII characters in the Null-terminated
    ASCII string specified by String.
  
    If Length > 0 and Destination is NULL, then ASSERT().
    If Length > 0 and Source is NULL, then ASSERT().
    If PcdMaximumAsciiStringLength is not zero and String contains more than
    PcdMaximumAsciiStringLength ASCII characters not including the Null-terminator,
    then ASSERT().
  
    @param  String  The pointer to a Null-terminated ASCII string.
  
    @return The length of String.
  
  **/
  UINTN
  EFIAPI
  AsciiStrLen (
    IN      CONST CHAR8               *String
    );
  
  
  /**
    Returns the size of a Null-terminated ASCII string in bytes, including the
    Null terminator.
  
    This function returns the size, in bytes, of the Null-terminated ASCII string
    specified by String.
  
    If String is NULL, then ASSERT().
    If PcdMaximumAsciiStringLength is not zero and String contains more than
    PcdMaximumAsciiStringLength ASCII characters not including the Null-terminator,
    then ASSERT().
  
    @param  String  The pointer to a Null-terminated ASCII string.
  
    @return The size of String.
  
  **/
  UINTN
  EFIAPI
  AsciiStrSize (
    IN      CONST CHAR8               *String
    );
  
  
  /**
    Compares two Null-terminated ASCII strings, and returns the difference
    between the first mismatched ASCII characters.
  
    This function compares the Null-terminated ASCII string FirstString to the
    Null-terminated ASCII string SecondString. If FirstString is identical to
    SecondString, then 0 is returned. Otherwise, the value returned is the first
    mismatched ASCII character in SecondString subtracted from the first
    mismatched ASCII character in FirstString.
  
    If FirstString is NULL, then ASSERT().
    If SecondString is NULL, then ASSERT().
    If PcdMaximumAsciiStringLength is not zero and FirstString contains more than
    PcdMaximumAsciiStringLength ASCII characters not including the Null-terminator,
    then ASSERT().
    If PcdMaximumAsciiStringLength is not zero and SecondString contains more
    than PcdMaximumAsciiStringLength ASCII characters not including the
    Null-terminator, then ASSERT().
  
    @param  FirstString   The pointer to a Null-terminated ASCII string.
    @param  SecondString  The pointer to a Null-terminated ASCII string.
  
    @retval ==0      FirstString is identical to SecondString.
    @retval !=0      FirstString is not identical to SecondString.
  
  **/
  INTN
  EFIAPI
  AsciiStrCmp (
    IN      CONST CHAR8               *FirstString,
    IN      CONST CHAR8               *SecondString
    );
  
  
  /**
    Performs a case insensitive comparison of two Null-terminated ASCII strings,
    and returns the difference between the first mismatched ASCII characters.
  
    This function performs a case insensitive comparison of the Null-terminated
    ASCII string FirstString to the Null-terminated ASCII string SecondString. If
    FirstString is identical to SecondString, then 0 is returned. Otherwise, the
    value returned is the first mismatched lower case ASCII character in
    SecondString subtracted from the first mismatched lower case ASCII character
    in FirstString.
  
    If FirstString is NULL, then ASSERT().
    If SecondString is NULL, then ASSERT().
    If PcdMaximumAsciiStringLength is not zero and FirstString contains more than
    PcdMaximumAsciiStringLength ASCII characters not including the Null-terminator,
    then ASSERT().
    If PcdMaximumAsciiStringLength is not zero and SecondString contains more
    than PcdMaximumAsciiStringLength ASCII characters not including the
    Null-terminator, then ASSERT().
  
    @param  FirstString   The pointer to a Null-terminated ASCII string.
    @param  SecondString  The pointer to a Null-terminated ASCII string.
  
    @retval ==0    FirstString is identical to SecondString using case insensitive
                   comparisons.
    @retval !=0    FirstString is not identical to SecondString using case
                   insensitive comparisons.
  
  **/
  INTN
  EFIAPI
  AsciiStriCmp (
    IN      CONST CHAR8               *FirstString,
    IN      CONST CHAR8               *SecondString
    );
  
  
  /**
    Compares two Null-terminated ASCII strings with maximum lengths, and returns
    the difference between the first mismatched ASCII characters.
  
    This function compares the Null-terminated ASCII string FirstString to the
    Null-terminated ASCII  string SecondString. At most, Length ASCII characters
    will be compared. If Length is 0, then 0 is returned. If FirstString is
    identical to SecondString, then 0 is returned. Otherwise, the value returned
    is the first mismatched ASCII character in SecondString subtracted from the
    first mismatched ASCII character in FirstString.
  
    If Length > 0 and FirstString is NULL, then ASSERT().
    If Length > 0 and SecondString is NULL, then ASSERT().
    If PcdMaximumAsciiStringLength is not zero, and Length is greater than
    PcdMaximumAsciiStringLength, then ASSERT().
    If PcdMaximumAsciiStringLength is not zero, and FirstString contains more than
    PcdMaximumAsciiStringLength ASCII characters, not including the Null-terminator,
    then ASSERT().
    If PcdMaximumAsciiStringLength is not zero, and SecondString contains more than
    PcdMaximumAsciiStringLength ASCII characters, not including the Null-terminator,
    then ASSERT().
  
    @param  FirstString   The pointer to a Null-terminated ASCII string.
    @param  SecondString  The pointer to a Null-terminated ASCII string.
    @param  Length        The maximum number of ASCII characters for compare.
  
    @retval ==0       FirstString is identical to SecondString.
    @retval !=0       FirstString is not identical to SecondString.
  
  **/
  INTN
  EFIAPI
  AsciiStrnCmp (
    IN      CONST CHAR8               *FirstString,
    IN      CONST CHAR8               *SecondString,
    IN      UINTN                     Length
    );
  
  
  #ifndef DISABLE_NEW_DEPRECATED_INTERFACES
  
  /**
    [ATTENTION] This function is deprecated for security reason.
  
    Concatenates one Null-terminated ASCII string to another Null-terminated
    ASCII string, and returns the concatenated ASCII string.
  
    This function concatenates two Null-terminated ASCII strings. The contents of
    Null-terminated ASCII string Source are concatenated to the end of Null-
    terminated ASCII string Destination. The Null-terminated concatenated ASCII
    String is returned.
  
    If Destination is NULL, then ASSERT().
    If Source is NULL, then ASSERT().
    If PcdMaximumAsciiStringLength is not zero and Destination contains more than
    PcdMaximumAsciiStringLength ASCII characters not including the Null-terminator,
    then ASSERT().
    If PcdMaximumAsciiStringLength is not zero and Source contains more than
    PcdMaximumAsciiStringLength ASCII characters not including the Null-terminator,
    then ASSERT().
    If PcdMaximumAsciiStringLength is not zero and concatenating Destination and
    Source results in a ASCII string with more than PcdMaximumAsciiStringLength
    ASCII characters, then ASSERT().
  
    @param  Destination The pointer to a Null-terminated ASCII string.
    @param  Source      The pointer to a Null-terminated ASCII string.
  
    @return Destination
  
  **/
  CHAR8 *
  EFIAPI
  AsciiStrCat (
    IN OUT CHAR8    *Destination,
    IN CONST CHAR8  *Source
    );
  
  
  /**
    [ATTENTION] This function is deprecated for security reason.
  
    Concatenates up to a specified length one Null-terminated ASCII string to
    the end of another Null-terminated ASCII string, and returns the
    concatenated ASCII string.
  
    This function concatenates two Null-terminated ASCII strings. The contents
    of Null-terminated ASCII string Source are concatenated to the end of Null-
    terminated ASCII string Destination, and Destination is returned. At most,
    Length ASCII characters are concatenated from Source to the end of
    Destination, and Destination is always Null-terminated. If Length is 0, then
    Destination is returned unmodified. If Source and Destination overlap, then
    the results are undefined.
  
    If Length > 0 and Destination is NULL, then ASSERT().
    If Length > 0 and Source is NULL, then ASSERT().
    If Source and Destination overlap, then ASSERT().
    If PcdMaximumAsciiStringLength is not zero, and Length is greater than
    PcdMaximumAsciiStringLength, then ASSERT().
    If PcdMaximumAsciiStringLength is not zero, and Destination contains more than
    PcdMaximumAsciiStringLength ASCII characters, not including the Null-terminator,
    then ASSERT().
    If PcdMaximumAsciiStringLength is not zero, and Source contains more than
    PcdMaximumAsciiStringLength ASCII characters, not including the Null-terminator,
    then ASSERT().
    If PcdMaximumAsciiStringLength is not zero, and concatenating Destination and
    Source results in a ASCII string with more than PcdMaximumAsciiStringLength
    ASCII characters, not including the Null-terminator, then ASSERT().
  
    @param  Destination The pointer to a Null-terminated ASCII string.
    @param  Source      The pointer to a Null-terminated ASCII string.
    @param  Length      The maximum number of ASCII characters to concatenate from
                        Source.
  
    @return Destination
  
  **/
  CHAR8 *
  EFIAPI
  AsciiStrnCat (
    IN OUT  CHAR8                     *Destination,
    IN      CONST CHAR8               *Source,
    IN      UINTN                     Length
    );
  #endif // !defined (DISABLE_NEW_DEPRECATED_INTERFACES)
  
  /**
    Returns the first occurrence of a Null-terminated ASCII sub-string
    in a Null-terminated ASCII string.
  
    This function scans the contents of the ASCII string specified by String
    and returns the first occurrence of SearchString. If SearchString is not
    found in String, then NULL is returned. If the length of SearchString is zero,
    then String is returned.
  
    If String is NULL, then ASSERT().
    If SearchString is NULL, then ASSERT().
  
    If PcdMaximumAsciiStringLength is not zero, and SearchString or
    String contains more than PcdMaximumAsciiStringLength Unicode characters
    not including the Null-terminator, then ASSERT().
  
    @param  String          The pointer to a Null-terminated ASCII string.
    @param  SearchString    The pointer to a Null-terminated ASCII string to search for.
  
    @retval NULL            If the SearchString does not appear in String.
    @retval others          If there is a match return the first occurrence of SearchingString.
                            If the length of SearchString is zero,return String.
  
  **/
  CHAR8 *
  EFIAPI
  AsciiStrStr (
    IN      CONST CHAR8               *String,
    IN      CONST CHAR8               *SearchString
    );
  
  
  /**
    Convert a Null-terminated ASCII decimal string to a value of type
    UINTN.
  
    This function returns a value of type UINTN by interpreting the contents
    of the ASCII string String as a decimal number. The format of the input
    ASCII string String is:
  
                      [spaces] [decimal digits].
  
    The valid decimal digit character is in the range [0-9]. The function will
    ignore the pad space, which includes spaces or tab characters, before the digits.
    The running zero in the beginning of [decimal digits] will be ignored. Then, the
    function stops at the first character that is a not a valid decimal character or
    Null-terminator, whichever on comes first.
  
    If String has only pad spaces, then 0 is returned.
    If String has no pad spaces or valid decimal digits, then 0 is returned.
    If the number represented by String overflows according to the range defined by
    UINTN, then MAX_UINTN is returned.
    If String is NULL, then ASSERT().
    If PcdMaximumAsciiStringLength is not zero, and String contains more than
    PcdMaximumAsciiStringLength ASCII characters not including the Null-terminator,
    then ASSERT().
  
    @param  String          The pointer to a Null-terminated ASCII string.
  
    @retval The value translated from String.
  
  **/
  UINTN
  EFIAPI
  AsciiStrDecimalToUintn (
    IN      CONST CHAR8               *String
    );
  
  
  /**
    Convert a Null-terminated ASCII decimal string to a value of type
    UINT64.
  
    This function returns a value of type UINT64 by interpreting the contents
    of the ASCII string String as a decimal number. The format of the input
    ASCII string String is:
  
                      [spaces] [decimal digits].
  
    The valid decimal digit character is in the range [0-9]. The function will
    ignore the pad space, which includes spaces or tab characters, before the digits.
    The running zero in the beginning of [decimal digits] will be ignored. Then, the
    function stops at the first character that is a not a valid decimal character or
    Null-terminator, whichever on comes first.
  
    If String has only pad spaces, then 0 is returned.
    If String has no pad spaces or valid decimal digits, then 0 is returned.
    If the number represented by String overflows according to the range defined by
    UINT64, then MAX_UINT64 is returned.
    If String is NULL, then ASSERT().
    If PcdMaximumAsciiStringLength is not zero, and String contains more than
    PcdMaximumAsciiStringLength ASCII characters not including the Null-terminator,
    then ASSERT().
  
    @param  String          The pointer to a Null-terminated ASCII string.
  
    @retval Value translated from String.
  
  **/
  UINT64
  EFIAPI
  AsciiStrDecimalToUint64 (
    IN      CONST CHAR8               *String
    );
  
  
  /**
    Convert a Null-terminated ASCII hexadecimal string to a value of type UINTN.
  
    This function returns a value of type UINTN by interpreting the contents of
    the ASCII string String as a hexadecimal number. The format of the input ASCII
    string String is:
  
                    [spaces][zeros][x][hexadecimal digits].
  
    The valid hexadecimal digit character is in the range [0-9], [a-f] and [A-F].
    The prefix "0x" is optional. Both "x" and "X" is allowed in "0x" prefix. If "x"
    appears in the input string, it must be prefixed with at least one 0. The function
    will ignore the pad space, which includes spaces or tab characters, before [zeros],
    [x] or [hexadecimal digits]. The running zero before [x] or [hexadecimal digits]
    will be ignored. Then, the decoding starts after [x] or the first valid hexadecimal
    digit. Then, the function stops at the first character that is a not a valid
    hexadecimal character or Null-terminator, whichever on comes first.
  
    If String has only pad spaces, then 0 is returned.
    If String has no leading pad spaces, leading zeros or valid hexadecimal digits, then
    0 is returned.
  
    If the number represented by String overflows according to the range defined by UINTN,
    then MAX_UINTN is returned.
    If String is NULL, then ASSERT().
    If PcdMaximumAsciiStringLength is not zero,
    and String contains more than PcdMaximumAsciiStringLength ASCII characters not including
    the Null-terminator, then ASSERT().
  
    @param  String          The pointer to a Null-terminated ASCII string.
  
    @retval Value translated from String.
  
  **/
  UINTN
  EFIAPI
  AsciiStrHexToUintn (
    IN      CONST CHAR8               *String
    );
  
  
  /**
    Convert a Null-terminated ASCII hexadecimal string to a value of type UINT64.
  
    This function returns a value of type UINT64 by interpreting the contents of
    the ASCII string String as a hexadecimal number. The format of the input ASCII
    string String is:
  
                    [spaces][zeros][x][hexadecimal digits].
  
    The valid hexadecimal digit character is in the range [0-9], [a-f] and [A-F].
    The prefix "0x" is optional. Both "x" and "X" is allowed in "0x" prefix. If "x"
    appears in the input string, it must be prefixed with at least one 0. The function
    will ignore the pad space, which includes spaces or tab characters, before [zeros],
    [x] or [hexadecimal digits]. The running zero before [x] or [hexadecimal digits]
    will be ignored. Then, the decoding starts after [x] or the first valid hexadecimal
    digit. Then, the function stops at the first character that is a not a valid
    hexadecimal character or Null-terminator, whichever on comes first.
  
    If String has only pad spaces, then 0 is returned.
    If String has no leading pad spaces, leading zeros or valid hexadecimal digits, then
    0 is returned.
  
    If the number represented by String overflows according to the range defined by UINT64,
    then MAX_UINT64 is returned.
    If String is NULL, then ASSERT().
    If PcdMaximumAsciiStringLength is not zero,
    and String contains more than PcdMaximumAsciiStringLength ASCII characters not including
    the Null-terminator, then ASSERT().
  
    @param  String          The pointer to a Null-terminated ASCII string.
  
    @retval Value translated from String.
  
  **/
  UINT64
  EFIAPI
  AsciiStrHexToUint64 (
    IN      CONST CHAR8                *String
    );
  
  /**
    Convert a Null-terminated ASCII string to IPv6 address and prefix length.
  
    This function outputs a value of type IPv6_ADDRESS and may output a value
    of type UINT8 by interpreting the contents of the ASCII string specified
    by String. The format of the input ASCII string String is as follows:
  
                    X:X:X:X:X:X:X:X[/P]
  
    X contains one to four hexadecimal digit characters in the range [0-9], [a-f] and
    [A-F]. X is converted to a value of type UINT16, whose low byte is stored in low
    memory address and high byte is stored in high memory address. P contains decimal
    digit characters in the range [0-9]. The running zero in the beginning of P will
    be ignored. /P is optional.
  
    When /P is not in the String, the function stops at the first character that is
    not a valid hexadecimal digit character after eight X's are converted.
  
    When /P is in the String, the function stops at the first character that is not
    a valid decimal digit character after P is converted.
  
    "::" can be used to compress one or more groups of X when X contains only 0.
    The "::" can only appear once in the String.
  
    If EndPointer is not NULL and Address is translated from String, a pointer
    to the character that stopped the scan is stored at the location pointed to
    by EndPointer.
  
    @param  String                   Pointer to a Null-terminated ASCII string.
    @param  EndPointer               Pointer to character that stops scan.
    @param  Address                  Pointer to the converted IPv6 address.
    @param  PrefixLength             Pointer to the converted IPv6 address prefix
                                     length. MAX_UINT8 is returned when /P is
                                     not in the String.
  
    @retval RETURN_SUCCESS           Address is translated from String.
    @retval RETURN_INVALID_PARAMETER If String is NULL.
                                     If Data is NULL.
    @retval RETURN_UNSUPPORTED       If X contains more than four hexadecimal
                                      digit characters.
                                     If String contains "::" and number of X
                                      is not less than 8.
                                     If P starts with character that is not a
                                      valid decimal digit character.
                                     If the decimal number converted from P
                                      exceeds 128.
  
  **/
  RETURN_STATUS
  EFIAPI
  AsciiStrToIpv6Address (
    IN  CONST CHAR8        *String,
    OUT CHAR8              **EndPointer, OPTIONAL
    OUT IPv6_ADDRESS       *Address,
    OUT UINT8              *PrefixLength OPTIONAL
    );
  
  /**
    Convert a Null-terminated ASCII string to IPv4 address and prefix length.
  
    This function outputs a value of type IPv4_ADDRESS and may output a value
    of type UINT8 by interpreting the contents of the ASCII string specified
    by String. The format of the input ASCII string String is as follows:
  
                    D.D.D.D[/P]
  
    D and P are decimal digit characters in the range [0-9]. The running zero in
    the beginning of D and P will be ignored. /P is optional.
  
    When /P is not in the String, the function stops at the first character that is
    not a valid decimal digit character after four D's are converted.
  
    When /P is in the String, the function stops at the first character that is not
    a valid decimal digit character after P is converted.
  
    If EndPointer is not NULL and Address is translated from String, a pointer
    to the character that stopped the scan is stored at the location pointed to
    by EndPointer.
  
    @param  String                   Pointer to a Null-terminated ASCII string.
    @param  EndPointer               Pointer to character that stops scan.
    @param  Address                  Pointer to the converted IPv4 address.
    @param  PrefixLength             Pointer to the converted IPv4 address prefix
                                     length. MAX_UINT8 is returned when /P is
                                     not in the String.
  
    @retval RETURN_SUCCESS           Address is translated from String.
    @retval RETURN_INVALID_PARAMETER If String is NULL.
                                     If Data is NULL.
    @retval RETURN_UNSUPPORTED       If String is not in the correct format.
                                     If any decimal number converted from D
                                      exceeds 255.
                                     If the decimal number converted from P
                                      exceeds 32.
  
  **/
  RETURN_STATUS
  EFIAPI
  AsciiStrToIpv4Address (
    IN  CONST CHAR8        *String,
    OUT CHAR8              **EndPointer, OPTIONAL
    OUT IPv4_ADDRESS       *Address,
    OUT UINT8              *PrefixLength OPTIONAL
    );
  
  /**
    Convert a Null-terminated ASCII GUID string to a value of type
    EFI_GUID.
  
    This function outputs a GUID value by interpreting the contents of
    the ASCII string specified by String. The format of the input
    ASCII string String consists of 36 characters, as follows:
  
                    aabbccdd-eeff-gghh-iijj-kkllmmnnoopp
  
    The pairs aa - pp are two characters in the range [0-9], [a-f] and
    [A-F], with each pair representing a single byte hexadecimal value.
  
    The mapping between String and the EFI_GUID structure is as follows:
                    aa          Data1[24:31]
                    bb          Data1[16:23]
                    cc          Data1[8:15]
                    dd          Data1[0:7]
                    ee          Data2[8:15]
                    ff          Data2[0:7]
                    gg          Data3[8:15]
                    hh          Data3[0:7]
                    ii          Data4[0:7]
                    jj          Data4[8:15]
                    kk          Data4[16:23]
                    ll          Data4[24:31]
                    mm          Data4[32:39]
                    nn          Data4[40:47]
                    oo          Data4[48:55]
                    pp          Data4[56:63]
  
    @param  String                   Pointer to a Null-terminated ASCII string.
    @param  Guid                     Pointer to the converted GUID.
  
    @retval RETURN_SUCCESS           Guid is translated from String.
    @retval RETURN_INVALID_PARAMETER If String is NULL.
                                     If Data is NULL.
    @retval RETURN_UNSUPPORTED       If String is not as the above format.
  
  **/
  RETURN_STATUS
  EFIAPI
  AsciiStrToGuid (
    IN  CONST CHAR8        *String,
    OUT GUID               *Guid
    );
  
  /**
    Convert a Null-terminated ASCII hexadecimal string to a byte array.
  
    This function outputs a byte array by interpreting the contents of
    the ASCII string specified by String in hexadecimal format. The format of
    the input ASCII string String is:
  
                    [XX]*
  
    X is a hexadecimal digit character in the range [0-9], [a-f] and [A-F].
    The function decodes every two hexadecimal digit characters as one byte. The
    decoding stops after Length of characters and outputs Buffer containing
    (Length / 2) bytes.
  
    @param  String                   Pointer to a Null-terminated ASCII string.
    @param  Length                   The number of ASCII characters to decode.
    @param  Buffer                   Pointer to the converted bytes array.
    @param  MaxBufferSize            The maximum size of Buffer.
  
    @retval RETURN_SUCCESS           Buffer is translated from String.
    @retval RETURN_INVALID_PARAMETER If String is NULL.
                                     If Data is NULL.
                                     If Length is not multiple of 2.
                                     If PcdMaximumAsciiStringLength is not zero,
                                      and Length is greater than
                                      PcdMaximumAsciiStringLength.
    @retval RETURN_UNSUPPORTED       If Length of characters from String contain
                                      a character that is not valid hexadecimal
                                      digit characters, or a Null-terminator.
    @retval RETURN_BUFFER_TOO_SMALL  If MaxBufferSize is less than (Length / 2).
  **/
  RETURN_STATUS
  EFIAPI
  AsciiStrHexToBytes (
    IN  CONST CHAR8        *String,
    IN  UINTN              Length,
    OUT UINT8              *Buffer,
    IN  UINTN              MaxBufferSize
    );
  
  #ifndef DISABLE_NEW_DEPRECATED_INTERFACES
  
  /**
    [ATTENTION] This function is deprecated for security reason.
  
    Convert one Null-terminated ASCII string to a Null-terminated
    Unicode string and returns the Unicode string.
  
    This function converts the contents of the ASCII string Source to the Unicode
    string Destination, and returns Destination.  The function terminates the
    Unicode string Destination by appending a Null-terminator character at the end.
    The caller is responsible to make sure Destination points to a buffer with size
    equal or greater than ((AsciiStrLen (Source) + 1) * sizeof (CHAR16)) in bytes.
  
    If Destination is NULL, then ASSERT().
    If Destination is not aligned on a 16-bit boundary, then ASSERT().
    If Source is NULL, then ASSERT().
    If Source and Destination overlap, then ASSERT().
    If PcdMaximumAsciiStringLength is not zero, and Source contains more than
    PcdMaximumAsciiStringLength ASCII characters not including the Null-terminator,
    then ASSERT().
    If PcdMaximumUnicodeStringLength is not zero, and Source contains more than
    PcdMaximumUnicodeStringLength ASCII characters not including the
    Null-terminator, then ASSERT().
  
    @param  Source        The pointer to a Null-terminated ASCII string.
    @param  Destination   The pointer to a Null-terminated Unicode string.
  
    @return Destination.
  
  **/
  CHAR16 *
  EFIAPI
  AsciiStrToUnicodeStr (
    IN      CONST CHAR8               *Source,
    OUT     CHAR16                    *Destination
    );
  
  #endif // !defined (DISABLE_NEW_DEPRECATED_INTERFACES)
  
  /**
    Convert one Null-terminated ASCII string to a Null-terminated
    Unicode string.
  
    This function is similar to StrCpyS.
  
    This function converts the contents of the ASCII string Source to the Unicode
    string Destination. The function terminates the Unicode string Destination by
    appending a Null-terminator character at the end.
  
    The caller is responsible to make sure Destination points to a buffer with size
    equal or greater than ((AsciiStrLen (Source) + 1) * sizeof (CHAR16)) in bytes.
  
    If Destination is not aligned on a 16-bit boundary, then ASSERT().
  
    If an error is returned, then the Destination is unmodified.
  
    @param  Source        The pointer to a Null-terminated ASCII string.
    @param  Destination   The pointer to a Null-terminated Unicode string.
    @param  DestMax       The maximum number of Destination Unicode
                          char, including terminating null char.
  
    @retval RETURN_SUCCESS           String is converted.
    @retval RETURN_BUFFER_TOO_SMALL  If DestMax is NOT greater than StrLen(Source).
    @retval RETURN_INVALID_PARAMETER If Destination is NULL.
                                     If Source is NULL.
                                     If PcdMaximumUnicodeStringLength is not zero,
                                      and DestMax is greater than
                                      PcdMaximumUnicodeStringLength.
                                     If PcdMaximumAsciiStringLength is not zero,
                                      and DestMax is greater than
                                      PcdMaximumAsciiStringLength.
                                     If DestMax is 0.
    @retval RETURN_ACCESS_DENIED     If Source and Destination overlap.
  
  **/
  RETURN_STATUS
  EFIAPI
  AsciiStrToUnicodeStrS (
    IN      CONST CHAR8               *Source,
    OUT     CHAR16                    *Destination,
    IN      UINTN                     DestMax
    );
  
  /**
    Convert not more than Length successive characters from a Null-terminated
    Ascii string to a Null-terminated Unicode string. If no null char is copied
    from Source, then Destination[Length] is always set to null.
  
    This function converts not more than Length successive characters from the
    Ascii string Source to the Unicode string Destination. The function
    terminates the Unicode string Destination by appending a Null-terminator
    character at the end.
  
    The caller is responsible to make sure Destination points to a buffer with
    size not smaller than
    ((MIN(AsciiStrLen(Source), Length) + 1) * sizeof (CHAR8)) in bytes.
  
    If Destination is not aligned on a 16-bit boundary, then ASSERT().
  
    If an error is returned, then Destination and DestinationLength are
    unmodified.
  
    @param  Source             The pointer to a Null-terminated Ascii string.
    @param  Length             The maximum number of Ascii characters to convert.
    @param  Destination        The pointer to a Null-terminated Unicode string.
    @param  DestMax            The maximum number of Destination Unicode char,
                               including terminating null char.
    @param  DestinationLength  The number of Ascii characters converted.
  
    @retval RETURN_SUCCESS            String is converted.
    @retval RETURN_INVALID_PARAMETER  If Destination is NULL.
                                      If Source is NULL.
                                      If DestinationLength is NULL.
                                      If PcdMaximumUnicodeStringLength is not
                                      zero, and Length or DestMax is greater than
                                      PcdMaximumUnicodeStringLength.
                                      If PcdMaximumAsciiStringLength is not zero,
                                      and Length or DestMax is greater than
                                      PcdMaximumAsciiStringLength.
                                      If DestMax is 0.
    @retval RETURN_BUFFER_TOO_SMALL   If DestMax is NOT greater than
                                      MIN(AsciiStrLen(Source), Length).
    @retval RETURN_ACCESS_DENIED      If Source and Destination overlap.
  
  **/
  RETURN_STATUS
  EFIAPI
  AsciiStrnToUnicodeStrS (
    IN      CONST CHAR8               *Source,
    IN      UINTN                     Length,
    OUT     CHAR16                    *Destination,
    IN      UINTN                     DestMax,
    OUT     UINTN                     *DestinationLength
    );
  
  /**
    Convert a Unicode character to upper case only if
    it maps to a valid small-case ASCII character.
  
    This internal function only deal with Unicode character
    which maps to a valid small-case ASCII character, i.e.
    L'a' to L'z'. For other Unicode character, the input character
    is returned directly.
  
    @param  Char  The character to convert.
  
    @retval LowerCharacter   If the Char is with range L'a' to L'z'.
    @retval Unchanged        Otherwise.
  
  **/
  CHAR16
  EFIAPI
  CharToUpper (
    IN      CHAR16                    Char
    );
  
  /**
    Converts a lowercase Ascii character to upper one.
  
    If Chr is lowercase Ascii character, then converts it to upper one.
  
    If Value >= 0xA0, then ASSERT().
    If (Value & 0x0F) >= 0x0A, then ASSERT().
  
    @param  Chr   one Ascii character
  
    @return The uppercase value of Ascii character
  
  **/
  CHAR8
  EFIAPI
  AsciiCharToUpper (
    IN      CHAR8                     Chr
    );
  
  /**
    Convert binary data to a Base64 encoded ascii string based on RFC4648.
  
    Produce a Null-terminated Ascii string in the output buffer specified by Destination and DestinationSize.
    The Ascii string is produced by converting the data string specified by Source and SourceLength.
  
    @param Source           Input UINT8 data
    @param SourceLength     Number of UINT8 bytes of data
    @param Destination      Pointer to output string buffer
    @param DestinationSize  Size of ascii buffer. Set to 0 to get the size needed.
                            Caller is responsible for passing in buffer of DestinationSize
  
    @retval RETURN_SUCCESS             When ascii buffer is filled in.
    @retval RETURN_INVALID_PARAMETER   If Source is NULL or DestinationSize is NULL.
    @retval RETURN_INVALID_PARAMETER   If SourceLength or DestinationSize is bigger than (MAX_ADDRESS - (UINTN)Destination).
    @retval RETURN_BUFFER_TOO_SMALL    If SourceLength is 0 and DestinationSize is <1.
    @retval RETURN_BUFFER_TOO_SMALL    If Destination is NULL or DestinationSize is smaller than required buffersize.
  
  **/
  RETURN_STATUS
  EFIAPI
  Base64Encode (
    IN  CONST UINT8  *Source,
    IN        UINTN   SourceLength,
    OUT       CHAR8  *Destination  OPTIONAL,
    IN OUT    UINTN  *DestinationSize
    );
  
  /**
    Decode Base64 ASCII encoded data to 8-bit binary representation, based on
    RFC4648.
  
    Decoding occurs according to "Table 1: The Base 64 Alphabet" in RFC4648.
  
    Whitespace is ignored at all positions:
    - 0x09 ('\t') horizontal tab
    - 0x0A ('\n') new line
    - 0x0B ('\v') vertical tab
    - 0x0C ('\f') form feed
    - 0x0D ('\r') carriage return
    - 0x20 (' ')  space
  
    The minimum amount of required padding (with ASCII 0x3D, '=') is tolerated
    and enforced at the end of the Base64 ASCII encoded data, and only there.
  
    Other characters outside of the encoding alphabet cause the function to
    reject the Base64 ASCII encoded data.
  
    @param[in] Source               Array of CHAR8 elements containing the Base64
                                    ASCII encoding. May be NULL if SourceSize is
                                    zero.
  
    @param[in] SourceSize           Number of CHAR8 elements in Source.
  
    @param[out] Destination         Array of UINT8 elements receiving the decoded
                                    8-bit binary representation. Allocated by the
                                    caller. May be NULL if DestinationSize is
                                    zero on input. If NULL, decoding is
                                    performed, but the 8-bit binary
                                    representation is not stored. If non-NULL and
                                    the function returns an error, the contents
                                    of Destination are indeterminate.
  
    @param[in,out] DestinationSize  On input, the number of UINT8 elements that
                                    the caller allocated for Destination. On
                                    output, if the function returns
                                    RETURN_SUCCESS or RETURN_BUFFER_TOO_SMALL,
                                    the number of UINT8 elements that are
                                    required for decoding the Base64 ASCII
                                    representation. If the function returns a
                                    value different from both RETURN_SUCCESS and
                                    RETURN_BUFFER_TOO_SMALL, then DestinationSize
                                    is indeterminate on output.
  
    @retval RETURN_SUCCESS            SourceSize CHAR8 elements at Source have
                                      been decoded to on-output DestinationSize
                                      UINT8 elements at Destination. Note that
                                      RETURN_SUCCESS covers the case when
                                      DestinationSize is zero on input, and
                                      Source decodes to zero bytes (due to
                                      containing at most ignored whitespace).
  
    @retval RETURN_BUFFER_TOO_SMALL   The input value of DestinationSize is not
                                      large enough for decoding SourceSize CHAR8
                                      elements at Source. The required number of
                                      UINT8 elements has been stored to
                                      DestinationSize.
  
    @retval RETURN_INVALID_PARAMETER  DestinationSize is NULL.
  
    @retval RETURN_INVALID_PARAMETER  Source is NULL, but SourceSize is not zero.
  
    @retval RETURN_INVALID_PARAMETER  Destination is NULL, but DestinationSize is
                                      not zero on input.
  
    @retval RETURN_INVALID_PARAMETER  Source is non-NULL, and (Source +
                                      SourceSize) would wrap around MAX_ADDRESS.
  
    @retval RETURN_INVALID_PARAMETER  Destination is non-NULL, and (Destination +
                                      DestinationSize) would wrap around
                                      MAX_ADDRESS, as specified on input.
  
    @retval RETURN_INVALID_PARAMETER  None of Source and Destination are NULL,
                                      and CHAR8[SourceSize] at Source overlaps
                                      UINT8[DestinationSize] at Destination, as
                                      specified on input.
  
    @retval RETURN_INVALID_PARAMETER  Invalid CHAR8 element encountered in
                                      Source.
  **/
  RETURN_STATUS
  EFIAPI
  Base64Decode (
    IN     CONST CHAR8 *Source          OPTIONAL,
    IN     UINTN       SourceSize,
    OUT    UINT8       *Destination     OPTIONAL,
    IN OUT UINTN       *DestinationSize
    );
  
  /**
    Converts an 8-bit value to an 8-bit BCD value.
  
    Converts the 8-bit value specified by Value to BCD. The BCD value is
    returned.
  
    If Value >= 100, then ASSERT().
  
    @param  Value The 8-bit value to convert to BCD. Range 0..99.
  
    @return The BCD value.
  
  **/
  UINT8
  EFIAPI
  DecimalToBcd8 (
    IN      UINT8                     Value
    );
  
  
  /**
    Converts an 8-bit BCD value to an 8-bit value.
  
    Converts the 8-bit BCD value specified by Value to an 8-bit value. The 8-bit
    value is returned.
  
    If Value >= 0xA0, then ASSERT().
    If (Value & 0x0F) >= 0x0A, then ASSERT().
  
    @param  Value The 8-bit BCD value to convert to an 8-bit value.
  
    @return The 8-bit value is returned.
  
  **/
  UINT8
  EFIAPI
  BcdToDecimal8 (
    IN      UINT8                     Value
    );
  
  //
  //  File Path Manipulation Functions
  //
  
  /**
    Removes the last directory or file entry in a path.
  
    @param[in, out] Path    The pointer to the path to modify.
  
    @retval FALSE     Nothing was found to remove.
    @retval TRUE      A directory or file was removed.
  **/
  BOOLEAN
  EFIAPI
  PathRemoveLastItem(
    IN OUT CHAR16 *Path
    );
  
  /**
    Function to clean up paths.
      - Single periods in the path are removed.
      - Double periods in the path are removed along with a single parent directory.
      - Forward slashes L'/' are converted to backward slashes L'\'.
  
    This will be done inline and the existing buffer may be larger than required
    upon completion.
  
    @param[in] Path       The pointer to the string containing the path.
  
    @return       Returns Path, otherwise returns NULL to indicate that an error has occurred.
  **/
  CHAR16*
  EFIAPI
  PathCleanUpDirectories(
    IN CHAR16 *Path
    );
  
  //
  // Linked List Functions and Macros
  //
  
  /**
    Initializes the head node of a doubly linked list that is declared as a
    global variable in a module.
  
    Initializes the forward and backward links of a new linked list. After
    initializing a linked list with this macro, the other linked list functions
    may be used to add and remove nodes from the linked list. This macro results
    in smaller executables by initializing the linked list in the data section,
    instead if calling the InitializeListHead() function to perform the
    equivalent operation.
  
    @param  ListHead  The head note of a list to initialize.
  
  **/
  #define INITIALIZE_LIST_HEAD_VARIABLE(ListHead)  {&(ListHead), &(ListHead)}
  
  /**
    Iterates over each node in a doubly linked list using each node's forward link.
  
    @param  Entry     A pointer to a list node used as a loop cursor during iteration
    @param  ListHead  The head node of the doubly linked list
  
  **/
  #define BASE_LIST_FOR_EACH(Entry, ListHead)    \
    for(Entry = (ListHead)->ForwardLink; Entry != (ListHead); Entry = Entry->ForwardLink)
  
  /**
    Iterates over each node in a doubly linked list using each node's forward link
    with safety against node removal.
  
    This macro uses NextEntry to temporarily store the next list node so the node
    pointed to by Entry may be deleted in the current loop iteration step and
    iteration can continue from the node pointed to by NextEntry.
  
    @param  Entry     A pointer to a list node used as a loop cursor during iteration
    @param  NextEntry A pointer to a list node used to temporarily store the next node
    @param  ListHead  The head node of the doubly linked list
  
  **/
  #define BASE_LIST_FOR_EACH_SAFE(Entry, NextEntry, ListHead)            \
    for(Entry = (ListHead)->ForwardLink, NextEntry = Entry->ForwardLink;\
        Entry != (ListHead); Entry = NextEntry, NextEntry = Entry->ForwardLink)
  
  /**
    Checks whether FirstEntry and SecondEntry are part of the same doubly-linked
    list.
  
    If FirstEntry is NULL, then ASSERT().
    If FirstEntry->ForwardLink is NULL, then ASSERT().
    If FirstEntry->BackLink is NULL, then ASSERT().
    If SecondEntry is NULL, then ASSERT();
    If PcdMaximumLinkedListLength is not zero, and List contains more than
    PcdMaximumLinkedListLength nodes, then ASSERT().
  
    @param  FirstEntry   A pointer to a node in a linked list.
    @param  SecondEntry  A pointer to the node to locate.
  
    @retval TRUE   SecondEntry is in the same doubly-linked list as FirstEntry.
    @retval FALSE  SecondEntry isn't in the same doubly-linked list as FirstEntry,
                   or FirstEntry is invalid.
  
  **/
  BOOLEAN
  EFIAPI
  IsNodeInList (
    IN      CONST LIST_ENTRY      *FirstEntry,
    IN      CONST LIST_ENTRY      *SecondEntry
    );
  
  
  /**
    Initializes the head node of a doubly linked list, and returns the pointer to
    the head node of the doubly linked list.
  
    Initializes the forward and backward links of a new linked list. After
    initializing a linked list with this function, the other linked list
    functions may be used to add and remove nodes from the linked list. It is up
    to the caller of this function to allocate the memory for ListHead.
  
    If ListHead is NULL, then ASSERT().
  
    @param  ListHead  A pointer to the head node of a new doubly linked list.
  
    @return ListHead
  
  **/
  LIST_ENTRY *
  EFIAPI
  InitializeListHead (
    IN OUT  LIST_ENTRY                *ListHead
    );
  
  
  /**
    Adds a node to the beginning of a doubly linked list, and returns the pointer
    to the head node of the doubly linked list.
  
    Adds the node Entry at the beginning of the doubly linked list denoted by
    ListHead, and returns ListHead.
  
    If ListHead is NULL, then ASSERT().
    If Entry is NULL, then ASSERT().
    If ListHead was not initialized with INTIALIZE_LIST_HEAD_VARIABLE() or
    InitializeListHead(), then ASSERT().
    If PcdMaximumLinkedListLength is not zero, and prior to insertion the number
    of nodes in ListHead, including the ListHead node, is greater than or
    equal to PcdMaximumLinkedListLength, then ASSERT().
  
    @param  ListHead  A pointer to the head node of a doubly linked list.
    @param  Entry     A pointer to a node that is to be inserted at the beginning
                      of a doubly linked list.
  
    @return ListHead
  
  **/
  LIST_ENTRY *
  EFIAPI
  InsertHeadList (
    IN OUT  LIST_ENTRY                *ListHead,
    IN OUT  LIST_ENTRY                *Entry
    );
  
  
  /**
    Adds a node to the end of a doubly linked list, and returns the pointer to
    the head node of the doubly linked list.
  
    Adds the node Entry to the end of the doubly linked list denoted by ListHead,
    and returns ListHead.
  
    If ListHead is NULL, then ASSERT().
    If Entry is NULL, then ASSERT().
    If ListHead was not initialized with INTIALIZE_LIST_HEAD_VARIABLE() or
    InitializeListHead(), then ASSERT().
    If PcdMaximumLinkedListLength is not zero, and prior to insertion the number
    of nodes in ListHead, including the ListHead node, is greater than or
    equal to PcdMaximumLinkedListLength, then ASSERT().
  
    @param  ListHead  A pointer to the head node of a doubly linked list.
    @param  Entry     A pointer to a node that is to be added at the end of the
                      doubly linked list.
  
    @return ListHead
  
  **/
  LIST_ENTRY *
  EFIAPI
  InsertTailList (
    IN OUT  LIST_ENTRY                *ListHead,
    IN OUT  LIST_ENTRY                *Entry
    );
  
  
  /**
    Retrieves the first node of a doubly linked list.
  
    Returns the first node of a doubly linked list.  List must have been
    initialized with INTIALIZE_LIST_HEAD_VARIABLE() or InitializeListHead().
    If List is empty, then List is returned.
  
    If List is NULL, then ASSERT().
    If List was not initialized with INTIALIZE_LIST_HEAD_VARIABLE() or
    InitializeListHead(), then ASSERT().
    If PcdMaximumLinkedListLength is not zero, and the number of nodes
    in List, including the List node, is greater than or equal to
    PcdMaximumLinkedListLength, then ASSERT().
  
    @param  List  A pointer to the head node of a doubly linked list.
  
    @return The first node of a doubly linked list.
    @retval List  The list is empty.
  
  **/
  LIST_ENTRY *
  EFIAPI
  GetFirstNode (
    IN      CONST LIST_ENTRY          *List
    );
  
  
  /**
    Retrieves the next node of a doubly linked list.
  
    Returns the node of a doubly linked list that follows Node.
    List must have been initialized with INTIALIZE_LIST_HEAD_VARIABLE()
    or InitializeListHead().  If List is empty, then List is returned.
  
    If List is NULL, then ASSERT().
    If Node is NULL, then ASSERT().
    If List was not initialized with INTIALIZE_LIST_HEAD_VARIABLE() or
    InitializeListHead(), then ASSERT().
    If PcdMaximumLinkedListLength is not zero, and List contains more than
    PcdMaximumLinkedListLength nodes, then ASSERT().
    If PcdVerifyNodeInList is TRUE and Node is not a node in List, then ASSERT().
  
    @param  List  A pointer to the head node of a doubly linked list.
    @param  Node  A pointer to a node in the doubly linked list.
  
    @return The pointer to the next node if one exists. Otherwise List is returned.
  
  **/
  LIST_ENTRY *
  EFIAPI
  GetNextNode (
    IN      CONST LIST_ENTRY          *List,
    IN      CONST LIST_ENTRY          *Node
    );
  
  
  /**
    Retrieves the previous node of a doubly linked list.
  
    Returns the node of a doubly linked list that precedes Node.
    List must have been initialized with INTIALIZE_LIST_HEAD_VARIABLE()
    or InitializeListHead().  If List is empty, then List is returned.
  
    If List is NULL, then ASSERT().
    If Node is NULL, then ASSERT().
    If List was not initialized with INTIALIZE_LIST_HEAD_VARIABLE() or
    InitializeListHead(), then ASSERT().
    If PcdMaximumLinkedListLength is not zero, and List contains more than
    PcdMaximumLinkedListLength nodes, then ASSERT().
    If PcdVerifyNodeInList is TRUE and Node is not a node in List, then ASSERT().
  
    @param  List  A pointer to the head node of a doubly linked list.
    @param  Node  A pointer to a node in the doubly linked list.
  
    @return The pointer to the previous node if one exists. Otherwise List is returned.
  
  **/
  LIST_ENTRY *
  EFIAPI
  GetPreviousNode (
    IN      CONST LIST_ENTRY          *List,
    IN      CONST LIST_ENTRY          *Node
    );
  
  
  /**
    Checks to see if a doubly linked list is empty or not.
  
    Checks to see if the doubly linked list is empty. If the linked list contains
    zero nodes, this function returns TRUE. Otherwise, it returns FALSE.
  
    If ListHead is NULL, then ASSERT().
    If ListHead was not initialized with INTIALIZE_LIST_HEAD_VARIABLE() or
    InitializeListHead(), then ASSERT().
    If PcdMaximumLinkedListLength is not zero, and the number of nodes
    in List, including the List node, is greater than or equal to
    PcdMaximumLinkedListLength, then ASSERT().
  
    @param  ListHead  A pointer to the head node of a doubly linked list.
  
    @retval TRUE  The linked list is empty.
    @retval FALSE The linked list is not empty.
  
  **/
  BOOLEAN
  EFIAPI
  IsListEmpty (
    IN      CONST LIST_ENTRY          *ListHead
    );
  
  
  /**
    Determines if a node in a doubly linked list is the head node of a the same
    doubly linked list.  This function is typically used to terminate a loop that
    traverses all the nodes in a doubly linked list starting with the head node.
  
    Returns TRUE if Node is equal to List.  Returns FALSE if Node is one of the
    nodes in the doubly linked list specified by List.  List must have been
    initialized with INTIALIZE_LIST_HEAD_VARIABLE() or InitializeListHead().
  
    If List is NULL, then ASSERT().
    If Node is NULL, then ASSERT().
    If List was not initialized with INTIALIZE_LIST_HEAD_VARIABLE() or InitializeListHead(),
    then ASSERT().
    If PcdMaximumLinkedListLength is not zero, and the number of nodes
    in List, including the List node, is greater than or equal to
    PcdMaximumLinkedListLength, then ASSERT().
    If PcdVerifyNodeInList is TRUE and Node is not a node in List the and Node is not equal
    to List, then ASSERT().
  
    @param  List  A pointer to the head node of a doubly linked list.
    @param  Node  A pointer to a node in the doubly linked list.
  
    @retval TRUE  Node is the head of the doubly-linked list pointed by List.
    @retval FALSE Node is not the head of the doubly-linked list pointed by List.
  
  **/
  BOOLEAN
  EFIAPI
  IsNull (
    IN      CONST LIST_ENTRY          *List,
    IN      CONST LIST_ENTRY          *Node
    );
  
  
  /**
    Determines if a node the last node in a doubly linked list.
  
    Returns TRUE if Node is the last node in the doubly linked list specified by
    List. Otherwise, FALSE is returned. List must have been initialized with
    INTIALIZE_LIST_HEAD_VARIABLE() or InitializeListHead().
  
    If List is NULL, then ASSERT().
    If Node is NULL, then ASSERT().
    If List was not initialized with INTIALIZE_LIST_HEAD_VARIABLE() or
    InitializeListHead(), then ASSERT().
    If PcdMaximumLinkedListLength is not zero, and the number of nodes
    in List, including the List node, is greater than or equal to
    PcdMaximumLinkedListLength, then ASSERT().
    If PcdVerifyNodeInList is TRUE and Node is not a node in List, then ASSERT().
  
    @param  List  A pointer to the head node of a doubly linked list.
    @param  Node  A pointer to a node in the doubly linked list.
  
    @retval TRUE  Node is the last node in the linked list.
    @retval FALSE Node is not the last node in the linked list.
  
  **/
  BOOLEAN
  EFIAPI
  IsNodeAtEnd (
    IN      CONST LIST_ENTRY          *List,
    IN      CONST LIST_ENTRY          *Node
    );
  
  
  /**
    Swaps the location of two nodes in a doubly linked list, and returns the
    first node after the swap.
  
    If FirstEntry is identical to SecondEntry, then SecondEntry is returned.
    Otherwise, the location of the FirstEntry node is swapped with the location
    of the SecondEntry node in a doubly linked list. SecondEntry must be in the
    same double linked list as FirstEntry and that double linked list must have
    been initialized with INTIALIZE_LIST_HEAD_VARIABLE() or InitializeListHead().
    SecondEntry is returned after the nodes are swapped.
  
    If FirstEntry is NULL, then ASSERT().
    If SecondEntry is NULL, then ASSERT().
    If PcdVerifyNodeInList is TRUE and SecondEntry and FirstEntry are not in the
    same linked list, then ASSERT().
    If PcdMaximumLinkedListLength is not zero, and the number of nodes in the
    linked list containing the FirstEntry and SecondEntry nodes, including
    the FirstEntry and SecondEntry nodes, is greater than or equal to
    PcdMaximumLinkedListLength, then ASSERT().
  
    @param  FirstEntry  A pointer to a node in a linked list.
    @param  SecondEntry A pointer to another node in the same linked list.
  
    @return SecondEntry.
  
  **/
  LIST_ENTRY *
  EFIAPI
  SwapListEntries (
    IN OUT  LIST_ENTRY                *FirstEntry,
    IN OUT  LIST_ENTRY                *SecondEntry
    );
  
  
  /**
    Removes a node from a doubly linked list, and returns the node that follows
    the removed node.
  
    Removes the node Entry from a doubly linked list. It is up to the caller of
    this function to release the memory used by this node if that is required. On
    exit, the node following Entry in the doubly linked list is returned. If
    Entry is the only node in the linked list, then the head node of the linked
    list is returned.
  
    If Entry is NULL, then ASSERT().
    If Entry is the head node of an empty list, then ASSERT().
    If PcdMaximumLinkedListLength is not zero, and the number of nodes in the
    linked list containing Entry, including the Entry node, is greater than
    or equal to PcdMaximumLinkedListLength, then ASSERT().
  
    @param  Entry A pointer to a node in a linked list.
  
    @return Entry.
  
  **/
  LIST_ENTRY *
  EFIAPI
  RemoveEntryList (
    IN      CONST LIST_ENTRY          *Entry
    );
  
  //
  // Math Services
  //
  
  /**
    Shifts a 64-bit integer left between 0 and 63 bits. The low bits are filled
    with zeros. The shifted value is returned.
  
    This function shifts the 64-bit value Operand to the left by Count bits. The
    low Count bits are set to zero. The shifted value is returned.
  
    If Count is greater than 63, then ASSERT().
  
    @param  Operand The 64-bit operand to shift left.
    @param  Count   The number of bits to shift left.
  
    @return Operand << Count.
  
  **/
  UINT64
  EFIAPI
  LShiftU64 (
    IN      UINT64                    Operand,
    IN      UINTN                     Count
    );
  
  
  /**
    Shifts a 64-bit integer right between 0 and 63 bits. This high bits are
    filled with zeros. The shifted value is returned.
  
    This function shifts the 64-bit value Operand to the right by Count bits. The
    high Count bits are set to zero. The shifted value is returned.
  
    If Count is greater than 63, then ASSERT().
  
    @param  Operand The 64-bit operand to shift right.
    @param  Count   The number of bits to shift right.
  
    @return Operand >> Count
  
  **/
  UINT64
  EFIAPI
  RShiftU64 (
    IN      UINT64                    Operand,
    IN      UINTN                     Count
    );
  
  
  /**
    Shifts a 64-bit integer right between 0 and 63 bits. The high bits are filled
    with original integer's bit 63. The shifted value is returned.
  
    This function shifts the 64-bit value Operand to the right by Count bits. The
    high Count bits are set to bit 63 of Operand.  The shifted value is returned.
  
    If Count is greater than 63, then ASSERT().
  
    @param  Operand The 64-bit operand to shift right.
    @param  Count   The number of bits to shift right.
  
    @return Operand >> Count
  
  **/
  UINT64
  EFIAPI
  ARShiftU64 (
    IN      UINT64                    Operand,
    IN      UINTN                     Count
    );
  
  
  /**
    Rotates a 32-bit integer left between 0 and 31 bits, filling the low bits
    with the high bits that were rotated.
  
    This function rotates the 32-bit value Operand to the left by Count bits. The
    low Count bits are fill with the high Count bits of Operand. The rotated
    value is returned.
  
    If Count is greater than 31, then ASSERT().
  
    @param  Operand The 32-bit operand to rotate left.
    @param  Count   The number of bits to rotate left.
  
    @return Operand << Count
  
  **/
  UINT32
  EFIAPI
  LRotU32 (
    IN      UINT32                    Operand,
    IN      UINTN                     Count
    );
  
  
  /**
    Rotates a 32-bit integer right between 0 and 31 bits, filling the high bits
    with the low bits that were rotated.
  
    This function rotates the 32-bit value Operand to the right by Count bits.
    The high Count bits are fill with the low Count bits of Operand. The rotated
    value is returned.
  
    If Count is greater than 31, then ASSERT().
  
    @param  Operand The 32-bit operand to rotate right.
    @param  Count   The number of bits to rotate right.
  
    @return Operand >> Count
  
  **/
  UINT32
  EFIAPI
  RRotU32 (
    IN      UINT32                    Operand,
    IN      UINTN                     Count
    );
  
  
  /**
    Rotates a 64-bit integer left between 0 and 63 bits, filling the low bits
    with the high bits that were rotated.
  
    This function rotates the 64-bit value Operand to the left by Count bits. The
    low Count bits are fill with the high Count bits of Operand. The rotated
    value is returned.
  
    If Count is greater than 63, then ASSERT().
  
    @param  Operand The 64-bit operand to rotate left.
    @param  Count   The number of bits to rotate left.
  
    @return Operand << Count
  
  **/
  UINT64
  EFIAPI
  LRotU64 (
    IN      UINT64                    Operand,
    IN      UINTN                     Count
    );
  
  
  /**
    Rotates a 64-bit integer right between 0 and 63 bits, filling the high bits
    with the high low bits that were rotated.
  
    This function rotates the 64-bit value Operand to the right by Count bits.
    The high Count bits are fill with the low Count bits of Operand. The rotated
    value is returned.
  
    If Count is greater than 63, then ASSERT().
  
    @param  Operand The 64-bit operand to rotate right.
    @param  Count   The number of bits to rotate right.
  
    @return Operand >> Count
  
  **/
  UINT64
  EFIAPI
  RRotU64 (
    IN      UINT64                    Operand,
    IN      UINTN                     Count
    );
  
  
  /**
    Returns the bit position of the lowest bit set in a 32-bit value.
  
    This function computes the bit position of the lowest bit set in the 32-bit
    value specified by Operand. If Operand is zero, then -1 is returned.
    Otherwise, a value between 0 and 31 is returned.
  
    @param  Operand The 32-bit operand to evaluate.
  
    @retval 0..31  The lowest bit set in Operand was found.
    @retval -1    Operand is zero.
  
  **/
  INTN
  EFIAPI
  LowBitSet32 (
    IN      UINT32                    Operand
    );
  
  
  /**
    Returns the bit position of the lowest bit set in a 64-bit value.
  
    This function computes the bit position of the lowest bit set in the 64-bit
    value specified by Operand. If Operand is zero, then -1 is returned.
    Otherwise, a value between 0 and 63 is returned.
  
    @param  Operand The 64-bit operand to evaluate.
  
    @retval 0..63  The lowest bit set in Operand was found.
    @retval -1    Operand is zero.
  
  
  **/
  INTN
  EFIAPI
  LowBitSet64 (
    IN      UINT64                    Operand
    );
  
  
  /**
    Returns the bit position of the highest bit set in a 32-bit value. Equivalent
    to log2(x).
  
    This function computes the bit position of the highest bit set in the 32-bit
    value specified by Operand. If Operand is zero, then -1 is returned.
    Otherwise, a value between 0 and 31 is returned.
  
    @param  Operand The 32-bit operand to evaluate.
  
    @retval 0..31  Position of the highest bit set in Operand if found.
    @retval -1    Operand is zero.
  
  **/
  INTN
  EFIAPI
  HighBitSet32 (
    IN      UINT32                    Operand
    );
  
  
  /**
    Returns the bit position of the highest bit set in a 64-bit value. Equivalent
    to log2(x).
  
    This function computes the bit position of the highest bit set in the 64-bit
    value specified by Operand. If Operand is zero, then -1 is returned.
    Otherwise, a value between 0 and 63 is returned.
  
    @param  Operand The 64-bit operand to evaluate.
  
    @retval 0..63   Position of the highest bit set in Operand if found.
    @retval -1     Operand is zero.
  
  **/
  INTN
  EFIAPI
  HighBitSet64 (
    IN      UINT64                    Operand
    );
  
  
  /**
    Returns the value of the highest bit set in a 32-bit value. Equivalent to
    1 << log2(x).
  
    This function computes the value of the highest bit set in the 32-bit value
    specified by Operand. If Operand is zero, then zero is returned.
  
    @param  Operand The 32-bit operand to evaluate.
  
    @return 1 << HighBitSet32(Operand)
    @retval 0 Operand is zero.
  
  **/
  UINT32
  EFIAPI
  GetPowerOfTwo32 (
    IN      UINT32                    Operand
    );
  
  
  /**
    Returns the value of the highest bit set in a 64-bit value. Equivalent to
    1 << log2(x).
  
    This function computes the value of the highest bit set in the 64-bit value
    specified by Operand. If Operand is zero, then zero is returned.
  
    @param  Operand The 64-bit operand to evaluate.
  
    @return 1 << HighBitSet64(Operand)
    @retval 0 Operand is zero.
  
  **/
  UINT64
  EFIAPI
  GetPowerOfTwo64 (
    IN      UINT64                    Operand
    );
  
  
  /**
    Switches the endianness of a 16-bit integer.
  
    This function swaps the bytes in a 16-bit unsigned value to switch the value
    from little endian to big endian or vice versa. The byte swapped value is
    returned.
  
    @param  Value A 16-bit unsigned value.
  
    @return The byte swapped Value.
  
  **/
  UINT16
  EFIAPI
  SwapBytes16 (
    IN      UINT16                    Value
    );
  
  
  /**
    Switches the endianness of a 32-bit integer.
  
    This function swaps the bytes in a 32-bit unsigned value to switch the value
    from little endian to big endian or vice versa. The byte swapped value is
    returned.
  
    @param  Value A 32-bit unsigned value.
  
    @return The byte swapped Value.
  
  **/
  UINT32
  EFIAPI
  SwapBytes32 (
    IN      UINT32                    Value
    );
  
  
  /**
    Switches the endianness of a 64-bit integer.
  
    This function swaps the bytes in a 64-bit unsigned value to switch the value
    from little endian to big endian or vice versa. The byte swapped value is
    returned.
  
    @param  Value A 64-bit unsigned value.
  
    @return The byte swapped Value.
  
  **/
  UINT64
  EFIAPI
  SwapBytes64 (
    IN      UINT64                    Value
    );
  
  
  /**
    Multiples a 64-bit unsigned integer by a 32-bit unsigned integer and
    generates a 64-bit unsigned result.
  
    This function multiples the 64-bit unsigned value Multiplicand by the 32-bit
    unsigned value Multiplier and generates a 64-bit unsigned result. This 64-
    bit unsigned result is returned.
  
    @param  Multiplicand  A 64-bit unsigned value.
    @param  Multiplier    A 32-bit unsigned value.
  
    @return Multiplicand * Multiplier
  
  **/
  UINT64
  EFIAPI
  MultU64x32 (
    IN      UINT64                    Multiplicand,
    IN      UINT32                    Multiplier
    );
  
  
  /**
    Multiples a 64-bit unsigned integer by a 64-bit unsigned integer and
    generates a 64-bit unsigned result.
  
    This function multiples the 64-bit unsigned value Multiplicand by the 64-bit
    unsigned value Multiplier and generates a 64-bit unsigned result. This 64-
    bit unsigned result is returned.
  
    @param  Multiplicand  A 64-bit unsigned value.
    @param  Multiplier    A 64-bit unsigned value.
  
    @return Multiplicand * Multiplier.
  
  **/
  UINT64
  EFIAPI
  MultU64x64 (
    IN      UINT64                    Multiplicand,
    IN      UINT64                    Multiplier
    );
  
  
  /**
    Multiples a 64-bit signed integer by a 64-bit signed integer and generates a
    64-bit signed result.
  
    This function multiples the 64-bit signed value Multiplicand by the 64-bit
    signed value Multiplier and generates a 64-bit signed result. This 64-bit
    signed result is returned.
  
    @param  Multiplicand  A 64-bit signed value.
    @param  Multiplier    A 64-bit signed value.
  
    @return Multiplicand * Multiplier
  
  **/
  INT64
  EFIAPI
  MultS64x64 (
    IN      INT64                     Multiplicand,
    IN      INT64                     Multiplier
    );
  
  
  /**
    Divides a 64-bit unsigned integer by a 32-bit unsigned integer and generates
    a 64-bit unsigned result.
  
    This function divides the 64-bit unsigned value Dividend by the 32-bit
    unsigned value Divisor and generates a 64-bit unsigned quotient. This
    function returns the 64-bit unsigned quotient.
  
    If Divisor is 0, then ASSERT().
  
    @param  Dividend  A 64-bit unsigned value.
    @param  Divisor   A 32-bit unsigned value.
  
    @return Dividend / Divisor.
  
  **/
  UINT64
  EFIAPI
  DivU64x32 (
    IN      UINT64                    Dividend,
    IN      UINT32                    Divisor
    );
  
  
  /**
    Divides a 64-bit unsigned integer by a 32-bit unsigned integer and generates
    a 32-bit unsigned remainder.
  
    This function divides the 64-bit unsigned value Dividend by the 32-bit
    unsigned value Divisor and generates a 32-bit remainder. This function
    returns the 32-bit unsigned remainder.
  
    If Divisor is 0, then ASSERT().
  
    @param  Dividend  A 64-bit unsigned value.
    @param  Divisor   A 32-bit unsigned value.
  
    @return Dividend % Divisor.
  
  **/
  UINT32
  EFIAPI
  ModU64x32 (
    IN      UINT64                    Dividend,
    IN      UINT32                    Divisor
    );
  
  
  /**
    Divides a 64-bit unsigned integer by a 32-bit unsigned integer and generates
    a 64-bit unsigned result and an optional 32-bit unsigned remainder.
  
    This function divides the 64-bit unsigned value Dividend by the 32-bit
    unsigned value Divisor and generates a 64-bit unsigned quotient. If Remainder
    is not NULL, then the 32-bit unsigned remainder is returned in Remainder.
    This function returns the 64-bit unsigned quotient.
  
    If Divisor is 0, then ASSERT().
  
    @param  Dividend  A 64-bit unsigned value.
    @param  Divisor   A 32-bit unsigned value.
    @param  Remainder A pointer to a 32-bit unsigned value. This parameter is
                      optional and may be NULL.
  
    @return Dividend / Divisor.
  
  **/
  UINT64
  EFIAPI
  DivU64x32Remainder (
    IN      UINT64                    Dividend,
    IN      UINT32                    Divisor,
    OUT     UINT32                    *Remainder  OPTIONAL
    );
  
  
  /**
    Divides a 64-bit unsigned integer by a 64-bit unsigned integer and generates
    a 64-bit unsigned result and an optional 64-bit unsigned remainder.
  
    This function divides the 64-bit unsigned value Dividend by the 64-bit
    unsigned value Divisor and generates a 64-bit unsigned quotient. If Remainder
    is not NULL, then the 64-bit unsigned remainder is returned in Remainder.
    This function returns the 64-bit unsigned quotient.
  
    If Divisor is 0, then ASSERT().
  
    @param  Dividend  A 64-bit unsigned value.
    @param  Divisor   A 64-bit unsigned value.
    @param  Remainder A pointer to a 64-bit unsigned value. This parameter is
                      optional and may be NULL.
  
    @return Dividend / Divisor.
  
  **/
  UINT64
  EFIAPI
  DivU64x64Remainder (
    IN      UINT64                    Dividend,
    IN      UINT64                    Divisor,
    OUT     UINT64                    *Remainder  OPTIONAL
    );
  
  
  /**
    Divides a 64-bit signed integer by a 64-bit signed integer and generates a
    64-bit signed result and a optional 64-bit signed remainder.
  
    This function divides the 64-bit signed value Dividend by the 64-bit signed
    value Divisor and generates a 64-bit signed quotient. If Remainder is not
    NULL, then the 64-bit signed remainder is returned in Remainder. This
    function returns the 64-bit signed quotient.
  
    It is the caller's responsibility to not call this function with a Divisor of 0.
    If Divisor is 0, then the quotient and remainder should be assumed to be
    the largest negative integer.
  
    If Divisor is 0, then ASSERT().
  
    @param  Dividend  A 64-bit signed value.
    @param  Divisor   A 64-bit signed value.
    @param  Remainder A pointer to a 64-bit signed value. This parameter is
                      optional and may be NULL.
  
    @return Dividend / Divisor.
  
  **/
  INT64
  EFIAPI
  DivS64x64Remainder (
    IN      INT64                     Dividend,
    IN      INT64                     Divisor,
    OUT     INT64                     *Remainder  OPTIONAL
    );
  
  
  /**
    Reads a 16-bit value from memory that may be unaligned.
  
    This function returns the 16-bit value pointed to by Buffer. The function
    guarantees that the read operation does not produce an alignment fault.
  
    If the Buffer is NULL, then ASSERT().
  
    @param  Buffer  The pointer to a 16-bit value that may be unaligned.
  
    @return The 16-bit value read from Buffer.
  
  **/
  UINT16
  EFIAPI
  ReadUnaligned16 (
    IN CONST UINT16              *Buffer
    );
  
  
  /**
    Writes a 16-bit value to memory that may be unaligned.
  
    This function writes the 16-bit value specified by Value to Buffer. Value is
    returned. The function guarantees that the write operation does not produce
    an alignment fault.
  
    If the Buffer is NULL, then ASSERT().
  
    @param  Buffer  The pointer to a 16-bit value that may be unaligned.
    @param  Value   16-bit value to write to Buffer.
  
    @return The 16-bit value to write to Buffer.
  
  **/
  UINT16
  EFIAPI
  WriteUnaligned16 (
    OUT UINT16                    *Buffer,
    IN  UINT16                    Value
    );
  
  
  /**
    Reads a 24-bit value from memory that may be unaligned.
  
    This function returns the 24-bit value pointed to by Buffer. The function
    guarantees that the read operation does not produce an alignment fault.
  
    If the Buffer is NULL, then ASSERT().
  
    @param  Buffer  The pointer to a 24-bit value that may be unaligned.
  
    @return The 24-bit value read from Buffer.
  
  **/
  UINT32
  EFIAPI
  ReadUnaligned24 (
    IN CONST UINT32              *Buffer
    );
  
  
  /**
    Writes a 24-bit value to memory that may be unaligned.
  
    This function writes the 24-bit value specified by Value to Buffer. Value is
    returned. The function guarantees that the write operation does not produce
    an alignment fault.
  
    If the Buffer is NULL, then ASSERT().
  
    @param  Buffer  The pointer to a 24-bit value that may be unaligned.
    @param  Value   24-bit value to write to Buffer.
  
    @return The 24-bit value to write to Buffer.
  
  **/
  UINT32
  EFIAPI
  WriteUnaligned24 (
    OUT UINT32                    *Buffer,
    IN  UINT32                    Value
    );
  
  
  /**
    Reads a 32-bit value from memory that may be unaligned.
  
    This function returns the 32-bit value pointed to by Buffer. The function
    guarantees that the read operation does not produce an alignment fault.
  
    If the Buffer is NULL, then ASSERT().
  
    @param  Buffer  The pointer to a 32-bit value that may be unaligned.
  
    @return The 32-bit value read from Buffer.
  
  **/
  UINT32
  EFIAPI
  ReadUnaligned32 (
    IN CONST UINT32              *Buffer
    );
  
  
  /**
    Writes a 32-bit value to memory that may be unaligned.
  
    This function writes the 32-bit value specified by Value to Buffer. Value is
    returned. The function guarantees that the write operation does not produce
    an alignment fault.
  
    If the Buffer is NULL, then ASSERT().
  
    @param  Buffer  The pointer to a 32-bit value that may be unaligned.
    @param  Value   32-bit value to write to Buffer.
  
    @return The 32-bit value to write to Buffer.
  
  **/
  UINT32
  EFIAPI
  WriteUnaligned32 (
    OUT UINT32                    *Buffer,
    IN  UINT32                    Value
    );
  
  
  /**
    Reads a 64-bit value from memory that may be unaligned.
  
    This function returns the 64-bit value pointed to by Buffer. The function
    guarantees that the read operation does not produce an alignment fault.
  
    If the Buffer is NULL, then ASSERT().
  
    @param  Buffer  The pointer to a 64-bit value that may be unaligned.
  
    @return The 64-bit value read from Buffer.
  
  **/
  UINT64
  EFIAPI
  ReadUnaligned64 (
    IN CONST UINT64              *Buffer
    );
  
  
  /**
    Writes a 64-bit value to memory that may be unaligned.
  
    This function writes the 64-bit value specified by Value to Buffer. Value is
    returned. The function guarantees that the write operation does not produce
    an alignment fault.
  
    If the Buffer is NULL, then ASSERT().
  
    @param  Buffer  The pointer to a 64-bit value that may be unaligned.
    @param  Value   64-bit value to write to Buffer.
  
    @return The 64-bit value to write to Buffer.
  
  **/
  UINT64
  EFIAPI
  WriteUnaligned64 (
    OUT UINT64                    *Buffer,
    IN  UINT64                    Value
    );
  
  
  //
  // Bit Field Functions
  //
  
  /**
    Returns a bit field from an 8-bit value.
  
    Returns the bitfield specified by the StartBit and the EndBit from Operand.
  
    If 8-bit operations are not supported, then ASSERT().
    If StartBit is greater than 7, then ASSERT().
    If EndBit is greater than 7, then ASSERT().
    If EndBit is less than StartBit, then ASSERT().
  
    @param  Operand   Operand on which to perform the bitfield operation.
    @param  StartBit  The ordinal of the least significant bit in the bit field.
                      Range 0..7.
    @param  EndBit    The ordinal of the most significant bit in the bit field.
                      Range 0..7.
  
    @return The bit field read.
  
  **/
  UINT8
  EFIAPI
  BitFieldRead8 (
    IN      UINT8                     Operand,
    IN      UINTN                     StartBit,
    IN      UINTN                     EndBit
    );
  
  
  /**
    Writes a bit field to an 8-bit value, and returns the result.
  
    Writes Value to the bit field specified by the StartBit and the EndBit in
    Operand. All other bits in Operand are preserved. The new 8-bit value is
    returned.
  
    If 8-bit operations are not supported, then ASSERT().
    If StartBit is greater than 7, then ASSERT().
    If EndBit is greater than 7, then ASSERT().
    If EndBit is less than StartBit, then ASSERT().
    If Value is larger than the bitmask value range specified by StartBit and EndBit, then ASSERT().
  
    @param  Operand   Operand on which to perform the bitfield operation.
    @param  StartBit  The ordinal of the least significant bit in the bit field.
                      Range 0..7.
    @param  EndBit    The ordinal of the most significant bit in the bit field.
                      Range 0..7.
    @param  Value     New value of the bit field.
  
    @return The new 8-bit value.
  
  **/
  UINT8
  EFIAPI
  BitFieldWrite8 (
    IN      UINT8                     Operand,
    IN      UINTN                     StartBit,
    IN      UINTN                     EndBit,
    IN      UINT8                     Value
    );
  
  
  /**
    Reads a bit field from an 8-bit value, performs a bitwise OR, and returns the
    result.
  
    Performs a bitwise OR between the bit field specified by StartBit
    and EndBit in Operand and the value specified by OrData. All other bits in
    Operand are preserved. The new 8-bit value is returned.
  
    If 8-bit operations are not supported, then ASSERT().
    If StartBit is greater than 7, then ASSERT().
    If EndBit is greater than 7, then ASSERT().
    If EndBit is less than StartBit, then ASSERT().
    If OrData is larger than the bitmask value range specified by StartBit and EndBit, then ASSERT().
  
    @param  Operand   Operand on which to perform the bitfield operation.
    @param  StartBit  The ordinal of the least significant bit in the bit field.
                      Range 0..7.
    @param  EndBit    The ordinal of the most significant bit in the bit field.
                      Range 0..7.
    @param  OrData    The value to OR with the read value from the value
  
    @return The new 8-bit value.
  
  **/
  UINT8
  EFIAPI
  BitFieldOr8 (
    IN      UINT8                     Operand,
    IN      UINTN                     StartBit,
    IN      UINTN                     EndBit,
    IN      UINT8                     OrData
    );
  
  
  /**
    Reads a bit field from an 8-bit value, performs a bitwise AND, and returns
    the result.
  
    Performs a bitwise AND between the bit field specified by StartBit and EndBit
    in Operand and the value specified by AndData. All other bits in Operand are
    preserved. The new 8-bit value is returned.
  
    If 8-bit operations are not supported, then ASSERT().
    If StartBit is greater than 7, then ASSERT().
    If EndBit is greater than 7, then ASSERT().
    If EndBit is less than StartBit, then ASSERT().
    If AndData is larger than the bitmask value range specified by StartBit and EndBit, then ASSERT().
  
    @param  Operand   Operand on which to perform the bitfield operation.
    @param  StartBit  The ordinal of the least significant bit in the bit field.
                      Range 0..7.
    @param  EndBit    The ordinal of the most significant bit in the bit field.
                      Range 0..7.
    @param  AndData   The value to AND with the read value from the value.
  
    @return The new 8-bit value.
  
  **/
  UINT8
  EFIAPI
  BitFieldAnd8 (
    IN      UINT8                     Operand,
    IN      UINTN                     StartBit,
    IN      UINTN                     EndBit,
    IN      UINT8                     AndData
    );
  
  
  /**
    Reads a bit field from an 8-bit value, performs a bitwise AND followed by a
    bitwise OR, and returns the result.
  
    Performs a bitwise AND between the bit field specified by StartBit and EndBit
    in Operand and the value specified by AndData, followed by a bitwise
    OR with value specified by OrData. All other bits in Operand are
    preserved. The new 8-bit value is returned.
  
    If 8-bit operations are not supported, then ASSERT().
    If StartBit is greater than 7, then ASSERT().
    If EndBit is greater than 7, then ASSERT().
    If EndBit is less than StartBit, then ASSERT().
    If AndData is larger than the bitmask value range specified by StartBit and EndBit, then ASSERT().
    If OrData is larger than the bitmask value range specified by StartBit and EndBit, then ASSERT().
  
    @param  Operand   Operand on which to perform the bitfield operation.
    @param  StartBit  The ordinal of the least significant bit in the bit field.
                      Range 0..7.
    @param  EndBit    The ordinal of the most significant bit in the bit field.
                      Range 0..7.
    @param  AndData   The value to AND with the read value from the value.
    @param  OrData    The value to OR with the result of the AND operation.
  
    @return The new 8-bit value.
  
  **/
  UINT8
  EFIAPI
  BitFieldAndThenOr8 (
    IN      UINT8                     Operand,
    IN      UINTN                     StartBit,
    IN      UINTN                     EndBit,
    IN      UINT8                     AndData,
    IN      UINT8                     OrData
    );
  
  
  /**
    Returns a bit field from a 16-bit value.
  
    Returns the bitfield specified by the StartBit and the EndBit from Operand.
  
    If 16-bit operations are not supported, then ASSERT().
    If StartBit is greater than 15, then ASSERT().
    If EndBit is greater than 15, then ASSERT().
    If EndBit is less than StartBit, then ASSERT().
  
    @param  Operand   Operand on which to perform the bitfield operation.
    @param  StartBit  The ordinal of the least significant bit in the bit field.
                      Range 0..15.
    @param  EndBit    The ordinal of the most significant bit in the bit field.
                      Range 0..15.
  
    @return The bit field read.
  
  **/
  UINT16
  EFIAPI
  BitFieldRead16 (
    IN      UINT16                    Operand,
    IN      UINTN                     StartBit,
    IN      UINTN                     EndBit
    );
  
  
  /**
    Writes a bit field to a 16-bit value, and returns the result.
  
    Writes Value to the bit field specified by the StartBit and the EndBit in
    Operand. All other bits in Operand are preserved. The new 16-bit value is
    returned.
  
    If 16-bit operations are not supported, then ASSERT().
    If StartBit is greater than 15, then ASSERT().
    If EndBit is greater than 15, then ASSERT().
    If EndBit is less than StartBit, then ASSERT().
    If Value is larger than the bitmask value range specified by StartBit and EndBit, then ASSERT().
  
    @param  Operand   Operand on which to perform the bitfield operation.
    @param  StartBit  The ordinal of the least significant bit in the bit field.
                      Range 0..15.
    @param  EndBit    The ordinal of the most significant bit in the bit field.
                      Range 0..15.
    @param  Value     New value of the bit field.
  
    @return The new 16-bit value.
  
  **/
  UINT16
  EFIAPI
  BitFieldWrite16 (
    IN      UINT16                    Operand,
    IN      UINTN                     StartBit,
    IN      UINTN                     EndBit,
    IN      UINT16                    Value
    );
  
  
  /**
    Reads a bit field from a 16-bit value, performs a bitwise OR, and returns the
    result.
  
    Performs a bitwise OR between the bit field specified by StartBit
    and EndBit in Operand and the value specified by OrData. All other bits in
    Operand are preserved. The new 16-bit value is returned.
  
    If 16-bit operations are not supported, then ASSERT().
    If StartBit is greater than 15, then ASSERT().
    If EndBit is greater than 15, then ASSERT().
    If EndBit is less than StartBit, then ASSERT().
    If OrData is larger than the bitmask value range specified by StartBit and EndBit, then ASSERT().
  
    @param  Operand   Operand on which to perform the bitfield operation.
    @param  StartBit  The ordinal of the least significant bit in the bit field.
                      Range 0..15.
    @param  EndBit    The ordinal of the most significant bit in the bit field.
                      Range 0..15.
    @param  OrData    The value to OR with the read value from the value
  
    @return The new 16-bit value.
  
  **/
  UINT16
  EFIAPI
  BitFieldOr16 (
    IN      UINT16                    Operand,
    IN      UINTN                     StartBit,
    IN      UINTN                     EndBit,
    IN      UINT16                    OrData
    );
  
  
  /**
    Reads a bit field from a 16-bit value, performs a bitwise AND, and returns
    the result.
  
    Performs a bitwise AND between the bit field specified by StartBit and EndBit
    in Operand and the value specified by AndData. All other bits in Operand are
    preserved. The new 16-bit value is returned.
  
    If 16-bit operations are not supported, then ASSERT().
    If StartBit is greater than 15, then ASSERT().
    If EndBit is greater than 15, then ASSERT().
    If EndBit is less than StartBit, then ASSERT().
    If AndData is larger than the bitmask value range specified by StartBit and EndBit, then ASSERT().
  
    @param  Operand   Operand on which to perform the bitfield operation.
    @param  StartBit  The ordinal of the least significant bit in the bit field.
                      Range 0..15.
    @param  EndBit    The ordinal of the most significant bit in the bit field.
                      Range 0..15.
    @param  AndData   The value to AND with the read value from the value
  
    @return The new 16-bit value.
  
  **/
  UINT16
  EFIAPI
  BitFieldAnd16 (
    IN      UINT16                    Operand,
    IN      UINTN                     StartBit,
    IN      UINTN                     EndBit,
    IN      UINT16                    AndData
    );
  
  
  /**
    Reads a bit field from a 16-bit value, performs a bitwise AND followed by a
    bitwise OR, and returns the result.
  
    Performs a bitwise AND between the bit field specified by StartBit and EndBit
    in Operand and the value specified by AndData, followed by a bitwise
    OR with value specified by OrData. All other bits in Operand are
    preserved. The new 16-bit value is returned.
  
    If 16-bit operations are not supported, then ASSERT().
    If StartBit is greater than 15, then ASSERT().
    If EndBit is greater than 15, then ASSERT().
    If EndBit is less than StartBit, then ASSERT().
    If AndData is larger than the bitmask value range specified by StartBit and EndBit, then ASSERT().
    If OrData is larger than the bitmask value range specified by StartBit and EndBit, then ASSERT().
  
    @param  Operand   Operand on which to perform the bitfield operation.
    @param  StartBit  The ordinal of the least significant bit in the bit field.
                      Range 0..15.
    @param  EndBit    The ordinal of the most significant bit in the bit field.
                      Range 0..15.
    @param  AndData   The value to AND with the read value from the value.
    @param  OrData    The value to OR with the result of the AND operation.
  
    @return The new 16-bit value.
  
  **/
  UINT16
  EFIAPI
  BitFieldAndThenOr16 (
    IN      UINT16                    Operand,
    IN      UINTN                     StartBit,
    IN      UINTN                     EndBit,
    IN      UINT16                    AndData,
    IN      UINT16                    OrData
    );
  
  
  /**
    Returns a bit field from a 32-bit value.
  
    Returns the bitfield specified by the StartBit and the EndBit from Operand.
  
    If 32-bit operations are not supported, then ASSERT().
    If StartBit is greater than 31, then ASSERT().
    If EndBit is greater than 31, then ASSERT().
    If EndBit is less than StartBit, then ASSERT().
  
    @param  Operand   Operand on which to perform the bitfield operation.
    @param  StartBit  The ordinal of the least significant bit in the bit field.
                      Range 0..31.
    @param  EndBit    The ordinal of the most significant bit in the bit field.
                      Range 0..31.
  
    @return The bit field read.
  
  **/
  UINT32
  EFIAPI
  BitFieldRead32 (
    IN      UINT32                    Operand,
    IN      UINTN                     StartBit,
    IN      UINTN                     EndBit
    );
  
  
  /**
    Writes a bit field to a 32-bit value, and returns the result.
  
    Writes Value to the bit field specified by the StartBit and the EndBit in
    Operand. All other bits in Operand are preserved. The new 32-bit value is
    returned.
  
    If 32-bit operations are not supported, then ASSERT().
    If StartBit is greater than 31, then ASSERT().
    If EndBit is greater than 31, then ASSERT().
    If EndBit is less than StartBit, then ASSERT().
    If Value is larger than the bitmask value range specified by StartBit and EndBit, then ASSERT().
  
    @param  Operand   Operand on which to perform the bitfield operation.
    @param  StartBit  The ordinal of the least significant bit in the bit field.
                      Range 0..31.
    @param  EndBit    The ordinal of the most significant bit in the bit field.
                      Range 0..31.
    @param  Value     New value of the bit field.
  
    @return The new 32-bit value.
  
  **/
  UINT32
  EFIAPI
  BitFieldWrite32 (
    IN      UINT32                    Operand,
    IN      UINTN                     StartBit,
    IN      UINTN                     EndBit,
    IN      UINT32                    Value
    );
  
  
  /**
    Reads a bit field from a 32-bit value, performs a bitwise OR, and returns the
    result.
  
    Performs a bitwise OR between the bit field specified by StartBit
    and EndBit in Operand and the value specified by OrData. All other bits in
    Operand are preserved. The new 32-bit value is returned.
  
    If 32-bit operations are not supported, then ASSERT().
    If StartBit is greater than 31, then ASSERT().
    If EndBit is greater than 31, then ASSERT().
    If EndBit is less than StartBit, then ASSERT().
    If OrData is larger than the bitmask value range specified by StartBit and EndBit, then ASSERT().
  
    @param  Operand   Operand on which to perform the bitfield operation.
    @param  StartBit  The ordinal of the least significant bit in the bit field.
                      Range 0..31.
    @param  EndBit    The ordinal of the most significant bit in the bit field.
                      Range 0..31.
    @param  OrData    The value to OR with the read value from the value.
  
    @return The new 32-bit value.
  
  **/
  UINT32
  EFIAPI
  BitFieldOr32 (
    IN      UINT32                    Operand,
    IN      UINTN                     StartBit,
    IN      UINTN                     EndBit,
    IN      UINT32                    OrData
    );
  
  
  /**
    Reads a bit field from a 32-bit value, performs a bitwise AND, and returns
    the result.
  
    Performs a bitwise AND between the bit field specified by StartBit and EndBit
    in Operand and the value specified by AndData. All other bits in Operand are
    preserved. The new 32-bit value is returned.
  
    If 32-bit operations are not supported, then ASSERT().
    If StartBit is greater than 31, then ASSERT().
    If EndBit is greater than 31, then ASSERT().
    If EndBit is less than StartBit, then ASSERT().
    If AndData is larger than the bitmask value range specified by StartBit and EndBit, then ASSERT().
  
    @param  Operand   Operand on which to perform the bitfield operation.
    @param  StartBit  The ordinal of the least significant bit in the bit field.
                      Range 0..31.
    @param  EndBit    The ordinal of the most significant bit in the bit field.
                      Range 0..31.
    @param  AndData   The value to AND with the read value from the value
  
    @return The new 32-bit value.
  
  **/
  UINT32
  EFIAPI
  BitFieldAnd32 (
    IN      UINT32                    Operand,
    IN      UINTN                     StartBit,
    IN      UINTN                     EndBit,
    IN      UINT32                    AndData
    );
  
  
  /**
    Reads a bit field from a 32-bit value, performs a bitwise AND followed by a
    bitwise OR, and returns the result.
  
    Performs a bitwise AND between the bit field specified by StartBit and EndBit
    in Operand and the value specified by AndData, followed by a bitwise
    OR with value specified by OrData. All other bits in Operand are
    preserved. The new 32-bit value is returned.
  
    If 32-bit operations are not supported, then ASSERT().
    If StartBit is greater than 31, then ASSERT().
    If EndBit is greater than 31, then ASSERT().
    If EndBit is less than StartBit, then ASSERT().
    If AndData is larger than the bitmask value range specified by StartBit and EndBit, then ASSERT().
    If OrData is larger than the bitmask value range specified by StartBit and EndBit, then ASSERT().
  
    @param  Operand   Operand on which to perform the bitfield operation.
    @param  StartBit  The ordinal of the least significant bit in the bit field.
                      Range 0..31.
    @param  EndBit    The ordinal of the most significant bit in the bit field.
                      Range 0..31.
    @param  AndData   The value to AND with the read value from the value.
    @param  OrData    The value to OR with the result of the AND operation.
  
    @return The new 32-bit value.
  
  **/
  UINT32
  EFIAPI
  BitFieldAndThenOr32 (
    IN      UINT32                    Operand,
    IN      UINTN                     StartBit,
    IN      UINTN                     EndBit,
    IN      UINT32                    AndData,
    IN      UINT32                    OrData
    );
  
  
  /**
    Returns a bit field from a 64-bit value.
  
    Returns the bitfield specified by the StartBit and the EndBit from Operand.
  
    If 64-bit operations are not supported, then ASSERT().
    If StartBit is greater than 63, then ASSERT().
    If EndBit is greater than 63, then ASSERT().
    If EndBit is less than StartBit, then ASSERT().
  
    @param  Operand   Operand on which to perform the bitfield operation.
    @param  StartBit  The ordinal of the least significant bit in the bit field.
                      Range 0..63.
    @param  EndBit    The ordinal of the most significant bit in the bit field.
                      Range 0..63.
  
    @return The bit field read.
  
  **/
  UINT64
  EFIAPI
  BitFieldRead64 (
    IN      UINT64                    Operand,
    IN      UINTN                     StartBit,
    IN      UINTN                     EndBit
    );
  
  
  /**
    Writes a bit field to a 64-bit value, and returns the result.
  
    Writes Value to the bit field specified by the StartBit and the EndBit in
    Operand. All other bits in Operand are preserved. The new 64-bit value is
    returned.
  
    If 64-bit operations are not supported, then ASSERT().
    If StartBit is greater than 63, then ASSERT().
    If EndBit is greater than 63, then ASSERT().
    If EndBit is less than StartBit, then ASSERT().
    If Value is larger than the bitmask value range specified by StartBit and EndBit, then ASSERT().
  
    @param  Operand   Operand on which to perform the bitfield operation.
    @param  StartBit  The ordinal of the least significant bit in the bit field.
                      Range 0..63.
    @param  EndBit    The ordinal of the most significant bit in the bit field.
                      Range 0..63.
    @param  Value     New value of the bit field.
  
    @return The new 64-bit value.
  
  **/
  UINT64
  EFIAPI
  BitFieldWrite64 (
    IN      UINT64                    Operand,
    IN      UINTN                     StartBit,
    IN      UINTN                     EndBit,
    IN      UINT64                    Value
    );
  
  
  /**
    Reads a bit field from a 64-bit value, performs a bitwise OR, and returns the
    result.
  
    Performs a bitwise OR between the bit field specified by StartBit
    and EndBit in Operand and the value specified by OrData. All other bits in
    Operand are preserved. The new 64-bit value is returned.
  
    If 64-bit operations are not supported, then ASSERT().
    If StartBit is greater than 63, then ASSERT().
    If EndBit is greater than 63, then ASSERT().
    If EndBit is less than StartBit, then ASSERT().
    If OrData is larger than the bitmask value range specified by StartBit and EndBit, then ASSERT().
  
    @param  Operand   Operand on which to perform the bitfield operation.
    @param  StartBit  The ordinal of the least significant bit in the bit field.
                      Range 0..63.
    @param  EndBit    The ordinal of the most significant bit in the bit field.
                      Range 0..63.
    @param  OrData    The value to OR with the read value from the value
  
    @return The new 64-bit value.
  
  **/
  UINT64
  EFIAPI
  BitFieldOr64 (
    IN      UINT64                    Operand,
    IN      UINTN                     StartBit,
    IN      UINTN                     EndBit,
    IN      UINT64                    OrData
    );
  
  
  /**
    Reads a bit field from a 64-bit value, performs a bitwise AND, and returns
    the result.
  
    Performs a bitwise AND between the bit field specified by StartBit and EndBit
    in Operand and the value specified by AndData. All other bits in Operand are
    preserved. The new 64-bit value is returned.
  
    If 64-bit operations are not supported, then ASSERT().
    If StartBit is greater than 63, then ASSERT().
    If EndBit is greater than 63, then ASSERT().
    If EndBit is less than StartBit, then ASSERT().
    If AndData is larger than the bitmask value range specified by StartBit and EndBit, then ASSERT().
  
    @param  Operand   Operand on which to perform the bitfield operation.
    @param  StartBit  The ordinal of the least significant bit in the bit field.
                      Range 0..63.
    @param  EndBit    The ordinal of the most significant bit in the bit field.
                      Range 0..63.
    @param  AndData   The value to AND with the read value from the value
  
    @return The new 64-bit value.
  
  **/
  UINT64
  EFIAPI
  BitFieldAnd64 (
    IN      UINT64                    Operand,
    IN      UINTN                     StartBit,
    IN      UINTN                     EndBit,
    IN      UINT64                    AndData
    );
  
  
  /**
    Reads a bit field from a 64-bit value, performs a bitwise AND followed by a
    bitwise OR, and returns the result.
  
    Performs a bitwise AND between the bit field specified by StartBit and EndBit
    in Operand and the value specified by AndData, followed by a bitwise
    OR with value specified by OrData. All other bits in Operand are
    preserved. The new 64-bit value is returned.
  
    If 64-bit operations are not supported, then ASSERT().
    If StartBit is greater than 63, then ASSERT().
    If EndBit is greater than 63, then ASSERT().
    If EndBit is less than StartBit, then ASSERT().
    If AndData is larger than the bitmask value range specified by StartBit and EndBit, then ASSERT().
    If OrData is larger than the bitmask value range specified by StartBit and EndBit, then ASSERT().
  
    @param  Operand   Operand on which to perform the bitfield operation.
    @param  StartBit  The ordinal of the least significant bit in the bit field.
                      Range 0..63.
    @param  EndBit    The ordinal of the most significant bit in the bit field.
                      Range 0..63.
    @param  AndData   The value to AND with the read value from the value.
    @param  OrData    The value to OR with the result of the AND operation.
  
    @return The new 64-bit value.
  
  **/
  UINT64
  EFIAPI
  BitFieldAndThenOr64 (
    IN      UINT64                    Operand,
    IN      UINTN                     StartBit,
    IN      UINTN                     EndBit,
    IN      UINT64                    AndData,
    IN      UINT64                    OrData
    );
  
  /**
    Reads a bit field from a 32-bit value, counts and returns
    the number of set bits.
  
    Counts the number of set bits in the  bit field specified by
    StartBit and EndBit in Operand. The count is returned.
  
    If StartBit is greater than 31, then ASSERT().
    If EndBit is greater than 31, then ASSERT().
    If EndBit is less than StartBit, then ASSERT().
  
    @param  Operand   Operand on which to perform the bitfield operation.
    @param  StartBit  The ordinal of the least significant bit in the bit field.
                      Range 0..31.
    @param  EndBit    The ordinal of the most significant bit in the bit field.
                      Range 0..31.
  
    @return The number of bits set between StartBit and EndBit.
  
  **/
  UINT8
  EFIAPI
  BitFieldCountOnes32 (
    IN       UINT32                   Operand,
    IN       UINTN                    StartBit,
    IN       UINTN                    EndBit
    );
  
  /**
     Reads a bit field from a 64-bit value, counts and returns
     the number of set bits.
  
     Counts the number of set bits in the  bit field specified by
     StartBit and EndBit in Operand. The count is returned.
  
     If StartBit is greater than 63, then ASSERT().
     If EndBit is greater than 63, then ASSERT().
     If EndBit is less than StartBit, then ASSERT().
  
     @param  Operand   Operand on which to perform the bitfield operation.
     @param  StartBit  The ordinal of the least significant bit in the bit field.
     Range 0..63.
     @param  EndBit    The ordinal of the most significant bit in the bit field.
     Range 0..63.
  
     @return The number of bits set between StartBit and EndBit.
  
  **/
  UINT8
  EFIAPI
  BitFieldCountOnes64 (
    IN       UINT64                   Operand,
    IN       UINTN                    StartBit,
    IN       UINTN                    EndBit
    );
  
  //
  // Base Library Checksum Functions
  //
  
  /**
    Returns the sum of all elements in a buffer in unit of UINT8.
    During calculation, the carry bits are dropped.
  
    This function calculates the sum of all elements in a buffer
    in unit of UINT8. The carry bits in result of addition are dropped.
    The result is returned as UINT8. If Length is Zero, then Zero is
    returned.
  
    If Buffer is NULL, then ASSERT().
    If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().
  
    @param  Buffer      The pointer to the buffer to carry out the sum operation.
    @param  Length      The size, in bytes, of Buffer.
  
    @return Sum         The sum of Buffer with carry bits dropped during additions.
  
  **/
  UINT8
  EFIAPI
  CalculateSum8 (
    IN      CONST UINT8              *Buffer,
    IN      UINTN                     Length
    );
  
  
  /**
    Returns the two's complement checksum of all elements in a buffer
    of 8-bit values.
  
    This function first calculates the sum of the 8-bit values in the
    buffer specified by Buffer and Length.  The carry bits in the result
    of addition are dropped. Then, the two's complement of the sum is
    returned.  If Length is 0, then 0 is returned.
  
    If Buffer is NULL, then ASSERT().
    If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().
  
    @param  Buffer      The pointer to the buffer to carry out the checksum operation.
    @param  Length      The size, in bytes, of Buffer.
  
    @return Checksum    The two's complement checksum of Buffer.
  
  **/
  UINT8
  EFIAPI
  CalculateCheckSum8 (
    IN      CONST UINT8              *Buffer,
    IN      UINTN                     Length
    );
  
  
  /**
    Returns the sum of all elements in a buffer of 16-bit values.  During
    calculation, the carry bits are dropped.
  
    This function calculates the sum of the 16-bit values in the buffer
    specified by Buffer and Length. The carry bits in result of addition are dropped.
    The 16-bit result is returned.  If Length is 0, then 0 is returned.
  
    If Buffer is NULL, then ASSERT().
    If Buffer is not aligned on a 16-bit boundary, then ASSERT().
    If Length is not aligned on a 16-bit boundary, then ASSERT().
    If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().
  
    @param  Buffer      The pointer to the buffer to carry out the sum operation.
    @param  Length      The size, in bytes, of Buffer.
  
    @return Sum         The sum of Buffer with carry bits dropped during additions.
  
  **/
  UINT16
  EFIAPI
  CalculateSum16 (
    IN      CONST UINT16             *Buffer,
    IN      UINTN                     Length
    );
  
  
  /**
    Returns the two's complement checksum of all elements in a buffer of
    16-bit values.
  
    This function first calculates the sum of the 16-bit values in the buffer
    specified by Buffer and Length.  The carry bits in the result of addition
    are dropped. Then, the two's complement of the sum is returned.  If Length
    is 0, then 0 is returned.
  
    If Buffer is NULL, then ASSERT().
    If Buffer is not aligned on a 16-bit boundary, then ASSERT().
    If Length is not aligned on a 16-bit boundary, then ASSERT().
    If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().
  
    @param  Buffer      The pointer to the buffer to carry out the checksum operation.
    @param  Length      The size, in bytes, of Buffer.
  
    @return Checksum    The two's complement checksum of Buffer.
  
  **/
  UINT16
  EFIAPI
  CalculateCheckSum16 (
    IN      CONST UINT16             *Buffer,
    IN      UINTN                     Length
    );
  
  
  /**
    Returns the sum of all elements in a buffer of 32-bit values. During
    calculation, the carry bits are dropped.
  
    This function calculates the sum of the 32-bit values in the buffer
    specified by Buffer and Length. The carry bits in result of addition are dropped.
    The 32-bit result is returned. If Length is 0, then 0 is returned.
  
    If Buffer is NULL, then ASSERT().
    If Buffer is not aligned on a 32-bit boundary, then ASSERT().
    If Length is not aligned on a 32-bit boundary, then ASSERT().
    If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().
  
    @param  Buffer      The pointer to the buffer to carry out the sum operation.
    @param  Length      The size, in bytes, of Buffer.
  
    @return Sum         The sum of Buffer with carry bits dropped during additions.
  
  **/
  UINT32
  EFIAPI
  CalculateSum32 (
    IN      CONST UINT32             *Buffer,
    IN      UINTN                     Length
    );
  
  
  /**
    Returns the two's complement checksum of all elements in a buffer of
    32-bit values.
  
    This function first calculates the sum of the 32-bit values in the buffer
    specified by Buffer and Length.  The carry bits in the result of addition
    are dropped. Then, the two's complement of the sum is returned.  If Length
    is 0, then 0 is returned.
  
    If Buffer is NULL, then ASSERT().
    If Buffer is not aligned on a 32-bit boundary, then ASSERT().
    If Length is not aligned on a 32-bit boundary, then ASSERT().
    If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().
  
    @param  Buffer      The pointer to the buffer to carry out the checksum operation.
    @param  Length      The size, in bytes, of Buffer.
  
    @return Checksum    The two's complement checksum of Buffer.
  
  **/
  UINT32
  EFIAPI
  CalculateCheckSum32 (
    IN      CONST UINT32             *Buffer,
    IN      UINTN                     Length
    );
  
  
  /**
    Returns the sum of all elements in a buffer of 64-bit values.  During
    calculation, the carry bits are dropped.
  
    This function calculates the sum of the 64-bit values in the buffer
    specified by Buffer and Length. The carry bits in result of addition are dropped.
    The 64-bit result is returned.  If Length is 0, then 0 is returned.
  
    If Buffer is NULL, then ASSERT().
    If Buffer is not aligned on a 64-bit boundary, then ASSERT().
    If Length is not aligned on a 64-bit boundary, then ASSERT().
    If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().
  
    @param  Buffer      The pointer to the buffer to carry out the sum operation.
    @param  Length      The size, in bytes, of Buffer.
  
    @return Sum         The sum of Buffer with carry bits dropped during additions.
  
  **/
  UINT64
  EFIAPI
  CalculateSum64 (
    IN      CONST UINT64             *Buffer,
    IN      UINTN                     Length
    );
  
  
  /**
    Returns the two's complement checksum of all elements in a buffer of
    64-bit values.
  
    This function first calculates the sum of the 64-bit values in the buffer
    specified by Buffer and Length.  The carry bits in the result of addition
    are dropped. Then, the two's complement of the sum is returned.  If Length
    is 0, then 0 is returned.
  
    If Buffer is NULL, then ASSERT().
    If Buffer is not aligned on a 64-bit boundary, then ASSERT().
    If Length is not aligned on a 64-bit boundary, then ASSERT().
    If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().
  
    @param  Buffer      The pointer to the buffer to carry out the checksum operation.
    @param  Length      The size, in bytes, of Buffer.
  
    @return Checksum    The two's complement checksum of Buffer.
  
  **/
  UINT64
  EFIAPI
  CalculateCheckSum64 (
    IN      CONST UINT64             *Buffer,
    IN      UINTN                     Length
    );
  
  /**
    Computes and returns a 32-bit CRC for a data buffer.
    CRC32 value bases on ITU-T V.42.
  
    If Buffer is NULL, then ASSERT().
    If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().
  
    @param[in]  Buffer       A pointer to the buffer on which the 32-bit CRC is to be computed.
    @param[in]  Length       The number of bytes in the buffer Data.
  
    @retval Crc32            The 32-bit CRC was computed for the data buffer.
  
  **/
  UINT32
  EFIAPI
  CalculateCrc32(
    IN  VOID                         *Buffer,
    IN  UINTN                        Length
    );
  
  //
  // Base Library CPU Functions
  //
  
  /**
    Function entry point used when a stack switch is requested with SwitchStack()
  
    @param  Context1        Context1 parameter passed into SwitchStack().
    @param  Context2        Context2 parameter passed into SwitchStack().
  
  **/
  typedef
  VOID
  (EFIAPI *SWITCH_STACK_ENTRY_POINT)(
    IN      VOID                      *Context1,  OPTIONAL
    IN      VOID                      *Context2   OPTIONAL
    );
  
  
  /**
    Used to serialize load and store operations.
  
    All loads and stores that proceed calls to this function are guaranteed to be
    globally visible when this function returns.
  
  **/
  VOID
  EFIAPI
  MemoryFence (
    VOID
    );
  
  
  /**
    Saves the current CPU context that can be restored with a call to LongJump()
    and returns 0.
  
    Saves the current CPU context in the buffer specified by JumpBuffer and
    returns 0. The initial call to SetJump() must always return 0. Subsequent
    calls to LongJump() cause a non-zero value to be returned by SetJump().
  
    If JumpBuffer is NULL, then ASSERT().
    For Itanium processors, if JumpBuffer is not aligned on a 16-byte boundary, then ASSERT().
  
    NOTE: The structure BASE_LIBRARY_JUMP_BUFFER is CPU architecture specific.
    The same structure must never be used for more than one CPU architecture context.
    For example, a BASE_LIBRARY_JUMP_BUFFER allocated by an IA-32 module must never be used from an x64 module.
    SetJump()/LongJump() is not currently supported for the EBC processor type.
  
    @param  JumpBuffer  A pointer to CPU context buffer.
  
    @retval 0 Indicates a return from SetJump().
  
  **/
  RETURNS_TWICE
  UINTN
  EFIAPI
  SetJump (
    OUT     BASE_LIBRARY_JUMP_BUFFER  *JumpBuffer
    );
  
  
  /**
    Restores the CPU context that was saved with SetJump().
  
    Restores the CPU context from the buffer specified by JumpBuffer. This
    function never returns to the caller. Instead is resumes execution based on
    the state of JumpBuffer.
  
    If JumpBuffer is NULL, then ASSERT().
    For Itanium processors, if JumpBuffer is not aligned on a 16-byte boundary, then ASSERT().
    If Value is 0, then ASSERT().
  
    @param  JumpBuffer  A pointer to CPU context buffer.
    @param  Value       The value to return when the SetJump() context is
                        restored and must be non-zero.
  
  **/
  VOID
  EFIAPI
  LongJump (
    IN      BASE_LIBRARY_JUMP_BUFFER  *JumpBuffer,
    IN      UINTN                     Value
    );
  
  
  /**
    Enables CPU interrupts.
  
  **/
  VOID
  EFIAPI
  EnableInterrupts (
    VOID
    );
  
  
  /**
    Disables CPU interrupts.
  
  **/
  VOID
  EFIAPI
  DisableInterrupts (
    VOID
    );
  
  
  /**
    Disables CPU interrupts and returns the interrupt state prior to the disable
    operation.
  
    @retval TRUE  CPU interrupts were enabled on entry to this call.
    @retval FALSE CPU interrupts were disabled on entry to this call.
  
  **/
  BOOLEAN
  EFIAPI
  SaveAndDisableInterrupts (
    VOID
    );
  
  
  /**
    Enables CPU interrupts for the smallest window required to capture any
    pending interrupts.
  
  **/
  VOID
  EFIAPI
  EnableDisableInterrupts (
    VOID
    );
  
  
  /**
    Retrieves the current CPU interrupt state.
  
    Returns TRUE if interrupts are currently enabled. Otherwise
    returns FALSE.
  
    @retval TRUE  CPU interrupts are enabled.
    @retval FALSE CPU interrupts are disabled.
  
  **/
  BOOLEAN
  EFIAPI
  GetInterruptState (
    VOID
    );
  
  
  /**
    Set the current CPU interrupt state.
  
    Sets the current CPU interrupt state to the state specified by
    InterruptState. If InterruptState is TRUE, then interrupts are enabled. If
    InterruptState is FALSE, then interrupts are disabled. InterruptState is
    returned.
  
    @param  InterruptState  TRUE if interrupts should enabled. FALSE if
                            interrupts should be disabled.
  
    @return InterruptState
  
  **/
  BOOLEAN
  EFIAPI
  SetInterruptState (
    IN      BOOLEAN                   InterruptState
    );
  
  
  /**
    Requests CPU to pause for a short period of time.
  
    Requests CPU to pause for a short period of time. Typically used in MP
    systems to prevent memory starvation while waiting for a spin lock.
  
  **/
  VOID
  EFIAPI
  CpuPause (
    VOID
    );
  
  
  /**
    Transfers control to a function starting with a new stack.
  
    Transfers control to the function specified by EntryPoint using the
    new stack specified by NewStack and passing in the parameters specified
    by Context1 and Context2.  Context1 and Context2 are optional and may
    be NULL.  The function EntryPoint must never return.  This function
    supports a variable number of arguments following the NewStack parameter.
    These additional arguments are ignored on IA-32, x64, and EBC architectures.
    Itanium processors expect one additional parameter of type VOID * that specifies
    the new backing store pointer.
  
    If EntryPoint is NULL, then ASSERT().
    If NewStack is NULL, then ASSERT().
  
    @param  EntryPoint  A pointer to function to call with the new stack.
    @param  Context1    A pointer to the context to pass into the EntryPoint
                        function.
    @param  Context2    A pointer to the context to pass into the EntryPoint
                        function.
    @param  NewStack    A pointer to the new stack to use for the EntryPoint
                        function.
    @param  ...         This variable argument list is ignored for IA-32, x64, and
                        EBC architectures.  For Itanium processors, this variable
                        argument list is expected to contain a single parameter of
                        type VOID * that specifies the new backing store pointer.
  
  
  **/
  VOID
  EFIAPI
  SwitchStack (
    IN      SWITCH_STACK_ENTRY_POINT  EntryPoint,
    IN      VOID                      *Context1,  OPTIONAL
    IN      VOID                      *Context2,  OPTIONAL
    IN      VOID                      *NewStack,
    ...
    );
  
  
  /**
    Generates a breakpoint on the CPU.
  
    Generates a breakpoint on the CPU. The breakpoint must be implemented such
    that code can resume normal execution after the breakpoint.
  
  **/
  VOID
  EFIAPI
  CpuBreakpoint (
    VOID
    );
  
  
  /**
    Executes an infinite loop.
  
    Forces the CPU to execute an infinite loop. A debugger may be used to skip
    past the loop and the code that follows the loop must execute properly. This
    implies that the infinite loop must not cause the code that follow it to be
    optimized away.
  
  **/
  VOID
  EFIAPI
  CpuDeadLoop (
    VOID
    );
  
  
  /**
    Uses as a barrier to stop speculative execution.
  
    Ensures that no later instruction will execute speculatively, until all prior
    instructions have completed.
  
  **/
  VOID
  EFIAPI
  SpeculationBarrier (
    VOID
    );
  
  
  #if defined (MDE_CPU_IA32) || defined (MDE_CPU_X64)
  ///
  /// IA32 and x64 Specific Functions.
  /// Byte packed structure for 16-bit Real Mode EFLAGS.
  ///
  typedef union {
    struct {
      UINT32  CF:1;           ///< Carry Flag.
      UINT32  Reserved_0:1;   ///< Reserved.
      UINT32  PF:1;           ///< Parity Flag.
      UINT32  Reserved_1:1;   ///< Reserved.
      UINT32  AF:1;           ///< Auxiliary Carry Flag.
      UINT32  Reserved_2:1;   ///< Reserved.
      UINT32  ZF:1;           ///< Zero Flag.
      UINT32  SF:1;           ///< Sign Flag.
      UINT32  TF:1;           ///< Trap Flag.
      UINT32  IF:1;           ///< Interrupt Enable Flag.
      UINT32  DF:1;           ///< Direction Flag.
      UINT32  OF:1;           ///< Overflow Flag.
      UINT32  IOPL:2;         ///< I/O Privilege Level.
      UINT32  NT:1;           ///< Nested Task.
      UINT32  Reserved_3:1;   ///< Reserved.
    } Bits;
    UINT16    Uint16;
  } IA32_FLAGS16;
  
  ///
  /// Byte packed structure for EFLAGS/RFLAGS.
  /// 32-bits on IA-32.
  /// 64-bits on x64.  The upper 32-bits on x64 are reserved.
  ///
  typedef union {
    struct {
      UINT32  CF:1;           ///< Carry Flag.
      UINT32  Reserved_0:1;   ///< Reserved.
      UINT32  PF:1;           ///< Parity Flag.
      UINT32  Reserved_1:1;   ///< Reserved.
      UINT32  AF:1;           ///< Auxiliary Carry Flag.
      UINT32  Reserved_2:1;   ///< Reserved.
      UINT32  ZF:1;           ///< Zero Flag.
      UINT32  SF:1;           ///< Sign Flag.
      UINT32  TF:1;           ///< Trap Flag.
      UINT32  IF:1;           ///< Interrupt Enable Flag.
      UINT32  DF:1;           ///< Direction Flag.
      UINT32  OF:1;           ///< Overflow Flag.
      UINT32  IOPL:2;         ///< I/O Privilege Level.
      UINT32  NT:1;           ///< Nested Task.
      UINT32  Reserved_3:1;   ///< Reserved.
      UINT32  RF:1;           ///< Resume Flag.
      UINT32  VM:1;           ///< Virtual 8086 Mode.
      UINT32  AC:1;           ///< Alignment Check.
      UINT32  VIF:1;          ///< Virtual Interrupt Flag.
      UINT32  VIP:1;          ///< Virtual Interrupt Pending.
      UINT32  ID:1;           ///< ID Flag.
      UINT32  Reserved_4:10;  ///< Reserved.
    } Bits;
    UINTN     UintN;
  } IA32_EFLAGS32;
  
  ///
  /// Byte packed structure for Control Register 0 (CR0).
  /// 32-bits on IA-32.
  /// 64-bits on x64.  The upper 32-bits on x64 are reserved.
  ///
  typedef union {
    struct {
      UINT32  PE:1;           ///< Protection Enable.
      UINT32  MP:1;           ///< Monitor Coprocessor.
      UINT32  EM:1;           ///< Emulation.
      UINT32  TS:1;           ///< Task Switched.
      UINT32  ET:1;           ///< Extension Type.
      UINT32  NE:1;           ///< Numeric Error.
      UINT32  Reserved_0:10;  ///< Reserved.
      UINT32  WP:1;           ///< Write Protect.
      UINT32  Reserved_1:1;   ///< Reserved.
      UINT32  AM:1;           ///< Alignment Mask.
      UINT32  Reserved_2:10;  ///< Reserved.
      UINT32  NW:1;           ///< Mot Write-through.
      UINT32  CD:1;           ///< Cache Disable.
      UINT32  PG:1;           ///< Paging.
    } Bits;
    UINTN     UintN;
  } IA32_CR0;
  
  ///
  /// Byte packed structure for Control Register 4 (CR4).
  /// 32-bits on IA-32.
  /// 64-bits on x64.  The upper 32-bits on x64 are reserved.
  ///
  typedef union {
    struct {
      UINT32  VME:1;          ///< Virtual-8086 Mode Extensions.
      UINT32  PVI:1;          ///< Protected-Mode Virtual Interrupts.
      UINT32  TSD:1;          ///< Time Stamp Disable.
      UINT32  DE:1;           ///< Debugging Extensions.
      UINT32  PSE:1;          ///< Page Size Extensions.
      UINT32  PAE:1;          ///< Physical Address Extension.
      UINT32  MCE:1;          ///< Machine Check Enable.
      UINT32  PGE:1;          ///< Page Global Enable.
      UINT32  PCE:1;          ///< Performance Monitoring Counter
                              ///< Enable.
      UINT32  OSFXSR:1;       ///< Operating System Support for
                              ///< FXSAVE and FXRSTOR instructions
      UINT32  OSXMMEXCPT:1;   ///< Operating System Support for
                              ///< Unmasked SIMD Floating Point
                              ///< Exceptions.
      UINT32  UMIP:1;         ///< User-Mode Instruction Prevention.
      UINT32  LA57:1;         ///< Linear Address 57bit.
      UINT32  VMXE:1;         ///< VMX Enable.
      UINT32  SMXE:1;         ///< SMX Enable.
      UINT32  Reserved_3:1;   ///< Reserved.
      UINT32  FSGSBASE:1;     ///< FSGSBASE Enable.
      UINT32  PCIDE:1;        ///< PCID Enable.
      UINT32  OSXSAVE:1;      ///< XSAVE and Processor Extended States Enable.
      UINT32  Reserved_4:1;   ///< Reserved.
      UINT32  SMEP:1;         ///< SMEP Enable.
      UINT32  SMAP:1;         ///< SMAP Enable.
      UINT32  PKE:1;          ///< Protection-Key Enable.
      UINT32  Reserved_5:9;   ///< Reserved.
    } Bits;
    UINTN     UintN;
  } IA32_CR4;
  
  ///
  /// Byte packed structure for a segment descriptor in a GDT/LDT.
  ///
  typedef union {
    struct {
      UINT32  LimitLow:16;
      UINT32  BaseLow:16;
      UINT32  BaseMid:8;
      UINT32  Type:4;
      UINT32  S:1;
      UINT32  DPL:2;
      UINT32  P:1;
      UINT32  LimitHigh:4;
      UINT32  AVL:1;
      UINT32  L:1;
      UINT32  DB:1;
      UINT32  G:1;
      UINT32  BaseHigh:8;
    } Bits;
    UINT64  Uint64;
  } IA32_SEGMENT_DESCRIPTOR;
  
  ///
  /// Byte packed structure for an IDTR, GDTR, LDTR descriptor.
  ///
  #pragma pack (1)
  typedef struct {
    UINT16  Limit;
    UINTN   Base;
  } IA32_DESCRIPTOR;
  #pragma pack ()
  
  #define IA32_IDT_GATE_TYPE_TASK          0x85
  #define IA32_IDT_GATE_TYPE_INTERRUPT_16  0x86
  #define IA32_IDT_GATE_TYPE_TRAP_16       0x87
  #define IA32_IDT_GATE_TYPE_INTERRUPT_32  0x8E
  #define IA32_IDT_GATE_TYPE_TRAP_32       0x8F
  
  #define IA32_GDT_TYPE_TSS               0x9
  #define IA32_GDT_ALIGNMENT              8
  
  #if defined (MDE_CPU_IA32)
  ///
  /// Byte packed structure for an IA-32 Interrupt Gate Descriptor.
  ///
  typedef union {
    struct {
      UINT32  OffsetLow:16;   ///< Offset bits 15..0.
      UINT32  Selector:16;    ///< Selector.
      UINT32  Reserved_0:8;   ///< Reserved.
      UINT32  GateType:8;     ///< Gate Type.  See #defines above.
      UINT32  OffsetHigh:16;  ///< Offset bits 31..16.
    } Bits;
    UINT64  Uint64;
  } IA32_IDT_GATE_DESCRIPTOR;
  
  #pragma pack (1)
  //
  // IA32 Task-State Segment Definition
  //
  typedef struct {
    UINT16    PreviousTaskLink;
    UINT16    Reserved_2;
    UINT32    ESP0;
    UINT16    SS0;
    UINT16    Reserved_10;
    UINT32    ESP1;
    UINT16    SS1;
    UINT16    Reserved_18;
    UINT32    ESP2;
    UINT16    SS2;
    UINT16    Reserved_26;
    UINT32    CR3;
    UINT32    EIP;
    UINT32    EFLAGS;
    UINT32    EAX;
    UINT32    ECX;
    UINT32    EDX;
    UINT32    EBX;
    UINT32    ESP;
    UINT32    EBP;
    UINT32    ESI;
    UINT32    EDI;
    UINT16    ES;
    UINT16    Reserved_74;
    UINT16    CS;
    UINT16    Reserved_78;
    UINT16    SS;
    UINT16    Reserved_82;
    UINT16    DS;
    UINT16    Reserved_86;
    UINT16    FS;
    UINT16    Reserved_90;
    UINT16    GS;
    UINT16    Reserved_94;
    UINT16    LDTSegmentSelector;
    UINT16    Reserved_98;
    UINT16    T;
    UINT16    IOMapBaseAddress;
  } IA32_TASK_STATE_SEGMENT;
  
  typedef union {
    struct {
      UINT32  LimitLow:16;    ///< Segment Limit 15..00
      UINT32  BaseLow:16;     ///< Base Address  15..00
      UINT32  BaseMid:8;      ///< Base Address  23..16
      UINT32  Type:4;         ///< Type (1 0 B 1)
      UINT32  Reserved_43:1;  ///< 0
      UINT32  DPL:2;          ///< Descriptor Privilege Level
      UINT32  P:1;            ///< Segment Present
      UINT32  LimitHigh:4;    ///< Segment Limit 19..16
      UINT32  AVL:1;          ///< Available for use by system software
      UINT32  Reserved_52:2;  ///< 0 0
      UINT32  G:1;            ///< Granularity
      UINT32  BaseHigh:8;     ///< Base Address 31..24
    } Bits;
    UINT64  Uint64;
  } IA32_TSS_DESCRIPTOR;
  #pragma pack ()
  
  #endif // defined (MDE_CPU_IA32)
  
  #if defined (MDE_CPU_X64)
  ///
  /// Byte packed structure for an x64 Interrupt Gate Descriptor.
  ///
  typedef union {
    struct {
      UINT32  OffsetLow:16;   ///< Offset bits 15..0.
      UINT32  Selector:16;    ///< Selector.
      UINT32  Reserved_0:8;   ///< Reserved.
      UINT32  GateType:8;     ///< Gate Type.  See #defines above.
      UINT32  OffsetHigh:16;  ///< Offset bits 31..16.
      UINT32  OffsetUpper:32; ///< Offset bits 63..32.
      UINT32  Reserved_1:32;  ///< Reserved.
    } Bits;
    struct {
      UINT64  Uint64;
      UINT64  Uint64_1;
    } Uint128;
  } IA32_IDT_GATE_DESCRIPTOR;
  
  #pragma pack (1)
  //
  // IA32 Task-State Segment Definition
  //
  typedef struct {
    UINT32    Reserved_0;
    UINT64    RSP0;
    UINT64    RSP1;
    UINT64    RSP2;
    UINT64    Reserved_28;
    UINT64    IST[7];
    UINT64    Reserved_92;
    UINT16    Reserved_100;
    UINT16    IOMapBaseAddress;
  } IA32_TASK_STATE_SEGMENT;
  
  typedef union {
    struct {
      UINT32  LimitLow:16;    ///< Segment Limit 15..00
      UINT32  BaseLow:16;     ///< Base Address  15..00
      UINT32  BaseMidl:8;     ///< Base Address  23..16
      UINT32  Type:4;         ///< Type (1 0 B 1)
      UINT32  Reserved_43:1;  ///< 0
      UINT32  DPL:2;          ///< Descriptor Privilege Level
      UINT32  P:1;            ///< Segment Present
      UINT32  LimitHigh:4;    ///< Segment Limit 19..16
      UINT32  AVL:1;          ///< Available for use by system software
      UINT32  Reserved_52:2;  ///< 0 0
      UINT32  G:1;            ///< Granularity
      UINT32  BaseMidh:8;     ///< Base Address  31..24
      UINT32  BaseHigh:32;    ///< Base Address  63..32
      UINT32  Reserved_96:32; ///< Reserved
    } Bits;
    struct {
      UINT64  Uint64;
      UINT64  Uint64_1;
    } Uint128;
  } IA32_TSS_DESCRIPTOR;
  #pragma pack ()
  
  #endif // defined (MDE_CPU_X64)
  
  ///
  /// Byte packed structure for an FP/SSE/SSE2 context.
  ///
  typedef struct {
    UINT8  Buffer[512];
  } IA32_FX_BUFFER;
  
  ///
  /// Structures for the 16-bit real mode thunks.
  ///
  typedef struct {
    UINT32                            Reserved1;
    UINT32                            Reserved2;
    UINT32                            Reserved3;
    UINT32                            Reserved4;
    UINT8                             BL;
    UINT8                             BH;
    UINT16                            Reserved5;
    UINT8                             DL;
    UINT8                             DH;
    UINT16                            Reserved6;
    UINT8                             CL;
    UINT8                             CH;
    UINT16                            Reserved7;
    UINT8                             AL;
    UINT8                             AH;
    UINT16                            Reserved8;
  } IA32_BYTE_REGS;
  
  typedef struct {
    UINT16                            DI;
    UINT16                            Reserved1;
    UINT16                            SI;
    UINT16                            Reserved2;
    UINT16                            BP;
    UINT16                            Reserved3;
    UINT16                            SP;
    UINT16                            Reserved4;
    UINT16                            BX;
    UINT16                            Reserved5;
    UINT16                            DX;
    UINT16                            Reserved6;
    UINT16                            CX;
    UINT16                            Reserved7;
    UINT16                            AX;
    UINT16                            Reserved8;
  } IA32_WORD_REGS;
  
  typedef struct {
    UINT32                            EDI;
    UINT32                            ESI;
    UINT32                            EBP;
    UINT32                            ESP;
    UINT32                            EBX;
    UINT32                            EDX;
    UINT32                            ECX;
    UINT32                            EAX;
    UINT16                            DS;
    UINT16                            ES;
    UINT16                            FS;
    UINT16                            GS;
    IA32_EFLAGS32                     EFLAGS;
    UINT32                            Eip;
    UINT16                            CS;
    UINT16                            SS;
  } IA32_DWORD_REGS;
  
  typedef union {
    IA32_DWORD_REGS                   E;
    IA32_WORD_REGS                    X;
    IA32_BYTE_REGS                    H;
  } IA32_REGISTER_SET;
  
  ///
  /// Byte packed structure for an 16-bit real mode thunks.
  ///
  typedef struct {
    IA32_REGISTER_SET                 *RealModeState;
    VOID                              *RealModeBuffer;
    UINT32                            RealModeBufferSize;
    UINT32                            ThunkAttributes;
  } THUNK_CONTEXT;
  
  #define THUNK_ATTRIBUTE_BIG_REAL_MODE             0x00000001
  #define THUNK_ATTRIBUTE_DISABLE_A20_MASK_INT_15   0x00000002
  #define THUNK_ATTRIBUTE_DISABLE_A20_MASK_KBD_CTRL 0x00000004
  
  ///
  /// Type definition for representing labels in NASM source code that allow for
  /// the patching of immediate operands of IA32 and X64 instructions.
  ///
  /// While the type is technically defined as a function type (note: not a
  /// pointer-to-function type), such labels in NASM source code never stand for
  /// actual functions, and identifiers declared with this function type should
  /// never be called. This is also why the EFIAPI calling convention specifier
  /// is missing from the typedef, and why the typedef does not follow the usual
  /// edk2 coding style for function (or pointer-to-function) typedefs. The VOID
  /// return type and the VOID argument list are merely artifacts.
  ///
  typedef VOID (X86_ASSEMBLY_PATCH_LABEL) (VOID);
  
  /**
    Retrieves CPUID information.
  
    Executes the CPUID instruction with EAX set to the value specified by Index.
    This function always returns Index.
    If Eax is not NULL, then the value of EAX after CPUID is returned in Eax.
    If Ebx is not NULL, then the value of EBX after CPUID is returned in Ebx.
    If Ecx is not NULL, then the value of ECX after CPUID is returned in Ecx.
    If Edx is not NULL, then the value of EDX after CPUID is returned in Edx.
    This function is only available on IA-32 and x64.
  
    @param  Index The 32-bit value to load into EAX prior to invoking the CPUID
                  instruction.
    @param  Eax   The pointer to the 32-bit EAX value returned by the CPUID
                  instruction. This is an optional parameter that may be NULL.
    @param  Ebx   The pointer to the 32-bit EBX value returned by the CPUID
                  instruction. This is an optional parameter that may be NULL.
    @param  Ecx   The pointer to the 32-bit ECX value returned by the CPUID
                  instruction. This is an optional parameter that may be NULL.
    @param  Edx   The pointer to the 32-bit EDX value returned by the CPUID
                  instruction. This is an optional parameter that may be NULL.
  
    @return Index.
  
  **/
  UINT32
  EFIAPI
  AsmCpuid (
    IN      UINT32                    Index,
    OUT     UINT32                    *Eax,  OPTIONAL
    OUT     UINT32                    *Ebx,  OPTIONAL
    OUT     UINT32                    *Ecx,  OPTIONAL
    OUT     UINT32                    *Edx   OPTIONAL
    );
  
  
  /**
    Retrieves CPUID information using an extended leaf identifier.
  
    Executes the CPUID instruction with EAX set to the value specified by Index
    and ECX set to the value specified by SubIndex. This function always returns
    Index. This function is only available on IA-32 and x64.
  
    If Eax is not NULL, then the value of EAX after CPUID is returned in Eax.
    If Ebx is not NULL, then the value of EBX after CPUID is returned in Ebx.
    If Ecx is not NULL, then the value of ECX after CPUID is returned in Ecx.
    If Edx is not NULL, then the value of EDX after CPUID is returned in Edx.
  
    @param  Index     The 32-bit value to load into EAX prior to invoking the
                      CPUID instruction.
    @param  SubIndex  The 32-bit value to load into ECX prior to invoking the
                      CPUID instruction.
    @param  Eax       The pointer to the 32-bit EAX value returned by the CPUID
                      instruction. This is an optional parameter that may be
                      NULL.
    @param  Ebx       The pointer to the 32-bit EBX value returned by the CPUID
                      instruction. This is an optional parameter that may be
                      NULL.
    @param  Ecx       The pointer to the 32-bit ECX value returned by the CPUID
                      instruction. This is an optional parameter that may be
                      NULL.
    @param  Edx       The pointer to the 32-bit EDX value returned by the CPUID
                      instruction. This is an optional parameter that may be
                      NULL.
  
    @return Index.
  
  **/
  UINT32
  EFIAPI
  AsmCpuidEx (
    IN      UINT32                    Index,
    IN      UINT32                    SubIndex,
    OUT     UINT32                    *Eax,  OPTIONAL
    OUT     UINT32                    *Ebx,  OPTIONAL
    OUT     UINT32                    *Ecx,  OPTIONAL
    OUT     UINT32                    *Edx   OPTIONAL
    );
  
  
  /**
    Set CD bit and clear NW bit of CR0 followed by a WBINVD.
  
    Disables the caches by setting the CD bit of CR0 to 1, clearing the NW bit of CR0 to 0,
    and executing a WBINVD instruction.  This function is only available on IA-32 and x64.
  
  **/
  VOID
  EFIAPI
  AsmDisableCache (
    VOID
    );
  
  
  /**
    Perform a WBINVD and clear both the CD and NW bits of CR0.
  
    Enables the caches by executing a WBINVD instruction and then clear both the CD and NW
    bits of CR0 to 0.  This function is only available on IA-32 and x64.
  
  **/
  VOID
  EFIAPI
  AsmEnableCache (
    VOID
    );
  
  
  /**
    Returns the lower 32-bits of a Machine Specific Register(MSR).
  
    Reads and returns the lower 32-bits of the MSR specified by Index.
    No parameter checking is performed on Index, and some Index values may cause
    CPU exceptions. The caller must either guarantee that Index is valid, or the
    caller must set up exception handlers to catch the exceptions. This function
    is only available on IA-32 and x64.
  
    @param  Index The 32-bit MSR index to read.
  
    @return The lower 32 bits of the MSR identified by Index.
  
  **/
  UINT32
  EFIAPI
  AsmReadMsr32 (
    IN      UINT32                    Index
    );
  
  
  /**
    Writes a 32-bit value to a Machine Specific Register(MSR), and returns the value.
    The upper 32-bits of the MSR are set to zero.
  
    Writes the 32-bit value specified by Value to the MSR specified by Index. The
    upper 32-bits of the MSR write are set to zero. The 32-bit value written to
    the MSR is returned. No parameter checking is performed on Index or Value,
    and some of these may cause CPU exceptions. The caller must either guarantee
    that Index and Value are valid, or the caller must establish proper exception
    handlers. This function is only available on IA-32 and x64.
  
    @param  Index The 32-bit MSR index to write.
    @param  Value The 32-bit value to write to the MSR.
  
    @return Value
  
  **/
  UINT32
  EFIAPI
  AsmWriteMsr32 (
    IN      UINT32                    Index,
    IN      UINT32                    Value
    );
  
  
  /**
    Reads a 64-bit MSR, performs a bitwise OR on the lower 32-bits, and
    writes the result back to the 64-bit MSR.
  
    Reads the 64-bit MSR specified by Index, performs a bitwise OR
    between the lower 32-bits of the read result and the value specified by
    OrData, and writes the result to the 64-bit MSR specified by Index. The lower
    32-bits of the value written to the MSR is returned. No parameter checking is
    performed on Index or OrData, and some of these may cause CPU exceptions. The
    caller must either guarantee that Index and OrData are valid, or the caller
    must establish proper exception handlers. This function is only available on
    IA-32 and x64.
  
    @param  Index   The 32-bit MSR index to write.
    @param  OrData  The value to OR with the read value from the MSR.
  
    @return The lower 32-bit value written to the MSR.
  
  **/
  UINT32
  EFIAPI
  AsmMsrOr32 (
    IN      UINT32                    Index,
    IN      UINT32                    OrData
    );
  
  
  /**
    Reads a 64-bit MSR, performs a bitwise AND on the lower 32-bits, and writes
    the result back to the 64-bit MSR.
  
    Reads the 64-bit MSR specified by Index, performs a bitwise AND between the
    lower 32-bits of the read result and the value specified by AndData, and
    writes the result to the 64-bit MSR specified by Index. The lower 32-bits of
    the value written to the MSR is returned. No parameter checking is performed
    on Index or AndData, and some of these may cause CPU exceptions. The caller
    must either guarantee that Index and AndData are valid, or the caller must
    establish proper exception handlers. This function is only available on IA-32
    and x64.
  
    @param  Index   The 32-bit MSR index to write.
    @param  AndData The value to AND with the read value from the MSR.
  
    @return The lower 32-bit value written to the MSR.
  
  **/
  UINT32
  EFIAPI
  AsmMsrAnd32 (
    IN      UINT32                    Index,
    IN      UINT32                    AndData
    );
  
  
  /**
    Reads a 64-bit MSR, performs a bitwise AND followed by a bitwise OR
    on the lower 32-bits, and writes the result back to the 64-bit MSR.
  
    Reads the 64-bit MSR specified by Index, performs a bitwise AND between the
    lower 32-bits of the read result and the value specified by AndData
    preserving the upper 32-bits, performs a bitwise OR between the
    result of the AND operation and the value specified by OrData, and writes the
    result to the 64-bit MSR specified by Address. The lower 32-bits of the value
    written to the MSR is returned. No parameter checking is performed on Index,
    AndData, or OrData, and some of these may cause CPU exceptions. The caller
    must either guarantee that Index, AndData, and OrData are valid, or the
    caller must establish proper exception handlers. This function is only
    available on IA-32 and x64.
  
    @param  Index   The 32-bit MSR index to write.
    @param  AndData The value to AND with the read value from the MSR.
    @param  OrData  The value to OR with the result of the AND operation.
  
    @return The lower 32-bit value written to the MSR.
  
  **/
  UINT32
  EFIAPI
  AsmMsrAndThenOr32 (
    IN      UINT32                    Index,
    IN      UINT32                    AndData,
    IN      UINT32                    OrData
    );
  
  
  /**
    Reads a bit field of an MSR.
  
    Reads the bit field in the lower 32-bits of a 64-bit MSR. The bit field is
    specified by the StartBit and the EndBit. The value of the bit field is
    returned. The caller must either guarantee that Index is valid, or the caller
    must set up exception handlers to catch the exceptions. This function is only
    available on IA-32 and x64.
  
    If StartBit is greater than 31, then ASSERT().
    If EndBit is greater than 31, then ASSERT().
    If EndBit is less than StartBit, then ASSERT().
  
    @param  Index     The 32-bit MSR index to read.
    @param  StartBit  The ordinal of the least significant bit in the bit field.
                      Range 0..31.
    @param  EndBit    The ordinal of the most significant bit in the bit field.
                      Range 0..31.
  
    @return The bit field read from the MSR.
  
  **/
  UINT32
  EFIAPI
  AsmMsrBitFieldRead32 (
    IN      UINT32                    Index,
    IN      UINTN                     StartBit,
    IN      UINTN                     EndBit
    );
  
  
  /**
    Writes a bit field to an MSR.
  
    Writes Value to a bit field in the lower 32-bits of a 64-bit MSR. The bit
    field is specified by the StartBit and the EndBit. All other bits in the
    destination MSR are preserved. The lower 32-bits of the MSR written is
    returned. The caller must either guarantee that Index and the data written
    is valid, or the caller must set up exception handlers to catch the exceptions.
    This function is only available on IA-32 and x64.
  
    If StartBit is greater than 31, then ASSERT().
    If EndBit is greater than 31, then ASSERT().
    If EndBit is less than StartBit, then ASSERT().
    If Value is larger than the bitmask value range specified by StartBit and EndBit, then ASSERT().
  
    @param  Index     The 32-bit MSR index to write.
    @param  StartBit  The ordinal of the least significant bit in the bit field.
                      Range 0..31.
    @param  EndBit    The ordinal of the most significant bit in the bit field.
                      Range 0..31.
    @param  Value     New value of the bit field.
  
    @return The lower 32-bit of the value written to the MSR.
  
  **/
  UINT32
  EFIAPI
  AsmMsrBitFieldWrite32 (
    IN      UINT32                    Index,
    IN      UINTN                     StartBit,
    IN      UINTN                     EndBit,
    IN      UINT32                    Value
    );
  
  
  /**
    Reads a bit field in a 64-bit MSR, performs a bitwise OR, and writes the
    result back to the bit field in the 64-bit MSR.
  
    Reads the 64-bit MSR specified by Index, performs a bitwise OR
    between the read result and the value specified by OrData, and writes the
    result to the 64-bit MSR specified by Index. The lower 32-bits of the value
    written to the MSR are returned. Extra left bits in OrData are stripped. The
    caller must either guarantee that Index and the data written is valid, or
    the caller must set up exception handlers to catch the exceptions. This
    function is only available on IA-32 and x64.
  
    If StartBit is greater than 31, then ASSERT().
    If EndBit is greater than 31, then ASSERT().
    If EndBit is less than StartBit, then ASSERT().
    If OrData is larger than the bitmask value range specified by StartBit and EndBit, then ASSERT().
  
    @param  Index     The 32-bit MSR index to write.
    @param  StartBit  The ordinal of the least significant bit in the bit field.
                      Range 0..31.
    @param  EndBit    The ordinal of the most significant bit in the bit field.
                      Range 0..31.
    @param  OrData    The value to OR with the read value from the MSR.
  
    @return The lower 32-bit of the value written to the MSR.
  
  **/
  UINT32
  EFIAPI
  AsmMsrBitFieldOr32 (
    IN      UINT32                    Index,
    IN      UINTN                     StartBit,
    IN      UINTN                     EndBit,
    IN      UINT32                    OrData
    );
  
  
  /**
    Reads a bit field in a 64-bit MSR, performs a bitwise AND, and writes the
    result back to the bit field in the 64-bit MSR.
  
    Reads the 64-bit MSR specified by Index, performs a bitwise AND between the
    read result and the value specified by AndData, and writes the result to the
    64-bit MSR specified by Index. The lower 32-bits of the value written to the
    MSR are returned. Extra left bits in AndData are stripped. The caller must
    either guarantee that Index and the data written is valid, or the caller must
    set up exception handlers to catch the exceptions. This function is only
    available on IA-32 and x64.
  
    If StartBit is greater than 31, then ASSERT().
    If EndBit is greater than 31, then ASSERT().
    If EndBit is less than StartBit, then ASSERT().
    If AndData is larger than the bitmask value range specified by StartBit and EndBit, then ASSERT().
  
    @param  Index     The 32-bit MSR index to write.
    @param  StartBit  The ordinal of the least significant bit in the bit field.
                      Range 0..31.
    @param  EndBit    The ordinal of the most significant bit in the bit field.
                      Range 0..31.
    @param  AndData   The value to AND with the read value from the MSR.
  
    @return The lower 32-bit of the value written to the MSR.
  
  **/
  UINT32
  EFIAPI
  AsmMsrBitFieldAnd32 (
    IN      UINT32                    Index,
    IN      UINTN                     StartBit,
    IN      UINTN                     EndBit,
    IN      UINT32                    AndData
    );
  
  
  /**
    Reads a bit field in a 64-bit MSR, performs a bitwise AND followed by a
    bitwise OR, and writes the result back to the bit field in the
    64-bit MSR.
  
    Reads the 64-bit MSR specified by Index, performs a bitwise AND followed by a
    bitwise OR between the read result and the value specified by
    AndData, and writes the result to the 64-bit MSR specified by Index. The
    lower 32-bits of the value written to the MSR are returned. Extra left bits
    in both AndData and OrData are stripped. The caller must either guarantee
    that Index and the data written is valid, or the caller must set up exception
    handlers to catch the exceptions. This function is only available on IA-32
    and x64.
  
    If StartBit is greater than 31, then ASSERT().
    If EndBit is greater than 31, then ASSERT().
    If EndBit is less than StartBit, then ASSERT().
    If AndData is larger than the bitmask value range specified by StartBit and EndBit, then ASSERT().
    If OrData is larger than the bitmask value range specified by StartBit and EndBit, then ASSERT().
  
    @param  Index     The 32-bit MSR index to write.
    @param  StartBit  The ordinal of the least significant bit in the bit field.
                      Range 0..31.
    @param  EndBit    The ordinal of the most significant bit in the bit field.
                      Range 0..31.
    @param  AndData   The value to AND with the read value from the MSR.
    @param  OrData    The value to OR with the result of the AND operation.
  
    @return The lower 32-bit of the value written to the MSR.
  
  **/
  UINT32
  EFIAPI
  AsmMsrBitFieldAndThenOr32 (
    IN      UINT32                    Index,
    IN      UINTN                     StartBit,
    IN      UINTN                     EndBit,
    IN      UINT32                    AndData,
    IN      UINT32                    OrData
    );
  
  
  /**
    Returns a 64-bit Machine Specific Register(MSR).
  
    Reads and returns the 64-bit MSR specified by Index. No parameter checking is
    performed on Index, and some Index values may cause CPU exceptions. The
    caller must either guarantee that Index is valid, or the caller must set up
    exception handlers to catch the exceptions. This function is only available
    on IA-32 and x64.
  
    @param  Index The 32-bit MSR index to read.
  
    @return The value of the MSR identified by Index.
  
  **/
  UINT64
  EFIAPI
  AsmReadMsr64 (
    IN      UINT32                    Index
    );
  
  
  /**
    Writes a 64-bit value to a Machine Specific Register(MSR), and returns the
    value.
  
    Writes the 64-bit value specified by Value to the MSR specified by Index. The
    64-bit value written to the MSR is returned. No parameter checking is
    performed on Index or Value, and some of these may cause CPU exceptions. The
    caller must either guarantee that Index and Value are valid, or the caller
    must establish proper exception handlers. This function is only available on
    IA-32 and x64.
  
    @param  Index The 32-bit MSR index to write.
    @param  Value The 64-bit value to write to the MSR.
  
    @return Value
  
  **/
  UINT64
  EFIAPI
  AsmWriteMsr64 (
    IN      UINT32                    Index,
    IN      UINT64                    Value
    );
  
  
  /**
    Reads a 64-bit MSR, performs a bitwise OR, and writes the result
    back to the 64-bit MSR.
  
    Reads the 64-bit MSR specified by Index, performs a bitwise OR
    between the read result and the value specified by OrData, and writes the
    result to the 64-bit MSR specified by Index. The value written to the MSR is
    returned. No parameter checking is performed on Index or OrData, and some of
    these may cause CPU exceptions. The caller must either guarantee that Index
    and OrData are valid, or the caller must establish proper exception handlers.
    This function is only available on IA-32 and x64.
  
    @param  Index   The 32-bit MSR index to write.
    @param  OrData  The value to OR with the read value from the MSR.
  
    @return The value written back to the MSR.
  
  **/
  UINT64
  EFIAPI
  AsmMsrOr64 (
    IN      UINT32                    Index,
    IN      UINT64                    OrData
    );
  
  
  /**
    Reads a 64-bit MSR, performs a bitwise AND, and writes the result back to the
    64-bit MSR.
  
    Reads the 64-bit MSR specified by Index, performs a bitwise AND between the
    read result and the value specified by OrData, and writes the result to the
    64-bit MSR specified by Index. The value written to the MSR is returned. No
    parameter checking is performed on Index or OrData, and some of these may
    cause CPU exceptions. The caller must either guarantee that Index and OrData
    are valid, or the caller must establish proper exception handlers. This
    function is only available on IA-32 and x64.
  
    @param  Index   The 32-bit MSR index to write.
    @param  AndData The value to AND with the read value from the MSR.
  
    @return The value written back to the MSR.
  
  **/
  UINT64
  EFIAPI
  AsmMsrAnd64 (
    IN      UINT32                    Index,
    IN      UINT64                    AndData
    );
  
  
  /**
    Reads a 64-bit MSR, performs a bitwise AND followed by a bitwise
    OR, and writes the result back to the 64-bit MSR.
  
    Reads the 64-bit MSR specified by Index, performs a bitwise AND between read
    result and the value specified by AndData, performs a bitwise OR
    between the result of the AND operation and the value specified by OrData,
    and writes the result to the 64-bit MSR specified by Index. The value written
    to the MSR is returned. No parameter checking is performed on Index, AndData,
    or OrData, and some of these may cause CPU exceptions. The caller must either
    guarantee that Index, AndData, and OrData are valid, or the caller must
    establish proper exception handlers. This function is only available on IA-32
    and x64.
  
    @param  Index   The 32-bit MSR index to write.
    @param  AndData The value to AND with the read value from the MSR.
    @param  OrData  The value to OR with the result of the AND operation.
  
    @return The value written back to the MSR.
  
  **/
  UINT64
  EFIAPI
  AsmMsrAndThenOr64 (
    IN      UINT32                    Index,
    IN      UINT64                    AndData,
    IN      UINT64                    OrData
    );
  
  
  /**
    Reads a bit field of an MSR.
  
    Reads the bit field in the 64-bit MSR. The bit field is specified by the
    StartBit and the EndBit. The value of the bit field is returned. The caller
    must either guarantee that Index is valid, or the caller must set up
    exception handlers to catch the exceptions. This function is only available
    on IA-32 and x64.
  
    If StartBit is greater than 63, then ASSERT().
    If EndBit is greater than 63, then ASSERT().
    If EndBit is less than StartBit, then ASSERT().
  
    @param  Index     The 32-bit MSR index to read.
    @param  StartBit  The ordinal of the least significant bit in the bit field.
                      Range 0..63.
    @param  EndBit    The ordinal of the most significant bit in the bit field.
                      Range 0..63.
  
    @return The value read from the MSR.
  
  **/
  UINT64
  EFIAPI
  AsmMsrBitFieldRead64 (
    IN      UINT32                    Index,
    IN      UINTN                     StartBit,
    IN      UINTN                     EndBit
    );
  
  
  /**
    Writes a bit field to an MSR.
  
    Writes Value to a bit field in a 64-bit MSR. The bit field is specified by
    the StartBit and the EndBit. All other bits in the destination MSR are
    preserved. The MSR written is returned. The caller must either guarantee
    that Index and the data written is valid, or the caller must set up exception
    handlers to catch the exceptions. This function is only available on IA-32 and x64.
  
    If StartBit is greater than 63, then ASSERT().
    If EndBit is greater than 63, then ASSERT().
    If EndBit is less than StartBit, then ASSERT().
    If Value is larger than the bitmask value range specified by StartBit and EndBit, then ASSERT().
  
    @param  Index     The 32-bit MSR index to write.
    @param  StartBit  The ordinal of the least significant bit in the bit field.
                      Range 0..63.
    @param  EndBit    The ordinal of the most significant bit in the bit field.
                      Range 0..63.
    @param  Value     New value of the bit field.
  
    @return The value written back to the MSR.
  
  **/
  UINT64
  EFIAPI
  AsmMsrBitFieldWrite64 (
    IN      UINT32                    Index,
    IN      UINTN                     StartBit,
    IN      UINTN                     EndBit,
    IN      UINT64                    Value
    );
  
  
  /**
    Reads a bit field in a 64-bit MSR, performs a bitwise OR, and
    writes the result back to the bit field in the 64-bit MSR.
  
    Reads the 64-bit MSR specified by Index, performs a bitwise OR
    between the read result and the value specified by OrData, and writes the
    result to the 64-bit MSR specified by Index. The value written to the MSR is
    returned. Extra left bits in OrData are stripped. The caller must either
    guarantee that Index and the data written is valid, or the caller must set up
    exception handlers to catch the exceptions. This function is only available
    on IA-32 and x64.
  
    If StartBit is greater than 63, then ASSERT().
    If EndBit is greater than 63, then ASSERT().
    If EndBit is less than StartBit, then ASSERT().
    If OrData is larger than the bitmask value range specified by StartBit and EndBit, then ASSERT().
  
    @param  Index     The 32-bit MSR index to write.
    @param  StartBit  The ordinal of the least significant bit in the bit field.
                      Range 0..63.
    @param  EndBit    The ordinal of the most significant bit in the bit field.
                      Range 0..63.
    @param  OrData    The value to OR with the read value from the bit field.
  
    @return The value written back to the MSR.
  
  **/
  UINT64
  EFIAPI
  AsmMsrBitFieldOr64 (
    IN      UINT32                    Index,
    IN      UINTN                     StartBit,
    IN      UINTN                     EndBit,
    IN      UINT64                    OrData
    );
  
  
  /**
    Reads a bit field in a 64-bit MSR, performs a bitwise AND, and writes the
    result back to the bit field in the 64-bit MSR.
  
    Reads the 64-bit MSR specified by Index, performs a bitwise AND between the
    read result and the value specified by AndData, and writes the result to the
    64-bit MSR specified by Index. The value written to the MSR is returned.
    Extra left bits in AndData are stripped. The caller must either guarantee
    that Index and the data written is valid, or the caller must set up exception
    handlers to catch the exceptions. This function is only available on IA-32
    and x64.
  
    If StartBit is greater than 63, then ASSERT().
    If EndBit is greater than 63, then ASSERT().
    If EndBit is less than StartBit, then ASSERT().
    If AndData is larger than the bitmask value range specified by StartBit and EndBit, then ASSERT().
  
    @param  Index     The 32-bit MSR index to write.
    @param  StartBit  The ordinal of the least significant bit in the bit field.
                      Range 0..63.
    @param  EndBit    The ordinal of the most significant bit in the bit field.
                      Range 0..63.
    @param  AndData   The value to AND with the read value from the bit field.
  
    @return The value written back to the MSR.
  
  **/
  UINT64
  EFIAPI
  AsmMsrBitFieldAnd64 (
    IN      UINT32                    Index,
    IN      UINTN                     StartBit,
    IN      UINTN                     EndBit,
    IN      UINT64                    AndData
    );
  
  
  /**
    Reads a bit field in a 64-bit MSR, performs a bitwise AND followed by a
    bitwise OR, and writes the result back to the bit field in the
    64-bit MSR.
  
    Reads the 64-bit MSR specified by Index, performs a bitwise AND followed by
    a bitwise OR between the read result and the value specified by
    AndData, and writes the result to the 64-bit MSR specified by Index. The
    value written to the MSR is returned. Extra left bits in both AndData and
    OrData are stripped. The caller must either guarantee that Index and the data
    written is valid, or the caller must set up exception handlers to catch the
    exceptions. This function is only available on IA-32 and x64.
  
    If StartBit is greater than 63, then ASSERT().
    If EndBit is greater than 63, then ASSERT().
    If EndBit is less than StartBit, then ASSERT().
    If AndData is larger than the bitmask value range specified by StartBit and EndBit, then ASSERT().
    If OrData is larger than the bitmask value range specified by StartBit and EndBit, then ASSERT().
  
    @param  Index     The 32-bit MSR index to write.
    @param  StartBit  The ordinal of the least significant bit in the bit field.
                      Range 0..63.
    @param  EndBit    The ordinal of the most significant bit in the bit field.
                      Range 0..63.
    @param  AndData   The value to AND with the read value from the bit field.
    @param  OrData    The value to OR with the result of the AND operation.
  
    @return The value written back to the MSR.
  
  **/
  UINT64
  EFIAPI
  AsmMsrBitFieldAndThenOr64 (
    IN      UINT32                    Index,
    IN      UINTN                     StartBit,
    IN      UINTN                     EndBit,
    IN      UINT64                    AndData,
    IN      UINT64                    OrData
    );
  
  
  /**
    Reads the current value of the EFLAGS register.
  
    Reads and returns the current value of the EFLAGS register. This function is
    only available on IA-32 and x64. This returns a 32-bit value on IA-32 and a
    64-bit value on x64.
  
    @return EFLAGS on IA-32 or RFLAGS on x64.
  
  **/
  UINTN
  EFIAPI
  AsmReadEflags (
    VOID
    );
  
  
  /**
    Reads the current value of the Control Register 0 (CR0).
  
    Reads and returns the current value of CR0. This function is only available
    on IA-32 and x64. This returns a 32-bit value on IA-32 and a 64-bit value on
    x64.
  
    @return The value of the Control Register 0 (CR0).
  
  **/
  UINTN
  EFIAPI
  AsmReadCr0 (
    VOID
    );
  
  
  /**
    Reads the current value of the Control Register 2 (CR2).
  
    Reads and returns the current value of CR2. This function is only available
    on IA-32 and x64. This returns a 32-bit value on IA-32 and a 64-bit value on
    x64.
  
    @return The value of the Control Register 2 (CR2).
  
  **/
  UINTN
  EFIAPI
  AsmReadCr2 (
    VOID
    );
  
  
  /**
    Reads the current value of the Control Register 3 (CR3).
  
    Reads and returns the current value of CR3. This function is only available
    on IA-32 and x64. This returns a 32-bit value on IA-32 and a 64-bit value on
    x64.
  
    @return The value of the Control Register 3 (CR3).
  
  **/
  UINTN
  EFIAPI
  AsmReadCr3 (
    VOID
    );
  
  
  /**
    Reads the current value of the Control Register 4 (CR4).
  
    Reads and returns the current value of CR4. This function is only available
    on IA-32 and x64. This returns a 32-bit value on IA-32 and a 64-bit value on
    x64.
  
    @return The value of the Control Register 4 (CR4).
  
  **/
  UINTN
  EFIAPI
  AsmReadCr4 (
    VOID
    );
  
  
  /**
    Writes a value to Control Register 0 (CR0).
  
    Writes and returns a new value to CR0. This function is only available on
    IA-32 and x64. This writes a 32-bit value on IA-32 and a 64-bit value on x64.
  
    @param  Cr0 The value to write to CR0.
  
    @return The value written to CR0.
  
  **/
  UINTN
  EFIAPI
  AsmWriteCr0 (
    UINTN  Cr0
    );
  
  
  /**
    Writes a value to Control Register 2 (CR2).
  
    Writes and returns a new value to CR2. This function is only available on
    IA-32 and x64. This writes a 32-bit value on IA-32 and a 64-bit value on x64.
  
    @param  Cr2 The value to write to CR2.
  
    @return The value written to CR2.
  
  **/
  UINTN
  EFIAPI
  AsmWriteCr2 (
    UINTN  Cr2
    );
  
  
  /**
    Writes a value to Control Register 3 (CR3).
  
    Writes and returns a new value to CR3. This function is only available on
    IA-32 and x64. This writes a 32-bit value on IA-32 and a 64-bit value on x64.
  
    @param  Cr3 The value to write to CR3.
  
    @return The value written to CR3.
  
  **/
  UINTN
  EFIAPI
  AsmWriteCr3 (
    UINTN  Cr3
    );
  
  
  /**
    Writes a value to Control Register 4 (CR4).
  
    Writes and returns a new value to CR4. This function is only available on
    IA-32 and x64. This writes a 32-bit value on IA-32 and a 64-bit value on x64.
  
    @param  Cr4 The value to write to CR4.
  
    @return The value written to CR4.
  
  **/
  UINTN
  EFIAPI
  AsmWriteCr4 (
    UINTN  Cr4
    );
  
  
  /**
    Reads the current value of Debug Register 0 (DR0).
  
    Reads and returns the current value of DR0. This function is only available
    on IA-32 and x64. This returns a 32-bit value on IA-32 and a 64-bit value on
    x64.
  
    @return The value of Debug Register 0 (DR0).
  
  **/
  UINTN
  EFIAPI
  AsmReadDr0 (
    VOID
    );
  
  
  /**
    Reads the current value of Debug Register 1 (DR1).
  
    Reads and returns the current value of DR1. This function is only available
    on IA-32 and x64. This returns a 32-bit value on IA-32 and a 64-bit value on
    x64.
  
    @return The value of Debug Register 1 (DR1).
  
  **/
  UINTN
  EFIAPI
  AsmReadDr1 (
    VOID
    );
  
  
  /**
    Reads the current value of Debug Register 2 (DR2).
  
    Reads and returns the current value of DR2. This function is only available
    on IA-32 and x64. This returns a 32-bit value on IA-32 and a 64-bit value on
    x64.
  
    @return The value of Debug Register 2 (DR2).
  
  **/
  UINTN
  EFIAPI
  AsmReadDr2 (
    VOID
    );
  
  
  /**
    Reads the current value of Debug Register 3 (DR3).
  
    Reads and returns the current value of DR3. This function is only available
    on IA-32 and x64. This returns a 32-bit value on IA-32 and a 64-bit value on
    x64.
  
    @return The value of Debug Register 3 (DR3).
  
  **/
  UINTN
  EFIAPI
  AsmReadDr3 (
    VOID
    );
  
  
  /**
    Reads the current value of Debug Register 4 (DR4).
  
    Reads and returns the current value of DR4. This function is only available
    on IA-32 and x64. This returns a 32-bit value on IA-32 and a 64-bit value on
    x64.
  
    @return The value of Debug Register 4 (DR4).
  
  **/
  UINTN
  EFIAPI
  AsmReadDr4 (
    VOID
    );
  
  
  /**
    Reads the current value of Debug Register 5 (DR5).
  
    Reads and returns the current value of DR5. This function is only available
    on IA-32 and x64. This returns a 32-bit value on IA-32 and a 64-bit value on
    x64.
  
    @return The value of Debug Register 5 (DR5).
  
  **/
  UINTN
  EFIAPI
  AsmReadDr5 (
    VOID
    );
  
  
  /**
    Reads the current value of Debug Register 6 (DR6).
  
    Reads and returns the current value of DR6. This function is only available
    on IA-32 and x64. This returns a 32-bit value on IA-32 and a 64-bit value on
    x64.
  
    @return The value of Debug Register 6 (DR6).
  
  **/
  UINTN
  EFIAPI
  AsmReadDr6 (
    VOID
    );
  
  
  /**
    Reads the current value of Debug Register 7 (DR7).
  
    Reads and returns the current value of DR7. This function is only available
    on IA-32 and x64. This returns a 32-bit value on IA-32 and a 64-bit value on
    x64.
  
    @return The value of Debug Register 7 (DR7).
  
  **/
  UINTN
  EFIAPI
  AsmReadDr7 (
    VOID
    );
  
  
  /**
    Writes a value to Debug Register 0 (DR0).
  
    Writes and returns a new value to DR0. This function is only available on
    IA-32 and x64. This writes a 32-bit value on IA-32 and a 64-bit value on x64.
  
    @param  Dr0 The value to write to Dr0.
  
    @return The value written to Debug Register 0 (DR0).
  
  **/
  UINTN
  EFIAPI
  AsmWriteDr0 (
    UINTN  Dr0
    );
  
  
  /**
    Writes a value to Debug Register 1 (DR1).
  
    Writes and returns a new value to DR1. This function is only available on
    IA-32 and x64. This writes a 32-bit value on IA-32 and a 64-bit value on x64.
  
    @param  Dr1 The value to write to Dr1.
  
    @return The value written to Debug Register 1 (DR1).
  
  **/
  UINTN
  EFIAPI
  AsmWriteDr1 (
    UINTN  Dr1
    );
  
  
  /**
    Writes a value to Debug Register 2 (DR2).
  
    Writes and returns a new value to DR2. This function is only available on
    IA-32 and x64. This writes a 32-bit value on IA-32 and a 64-bit value on x64.
  
    @param  Dr2 The value to write to Dr2.
  
    @return The value written to Debug Register 2 (DR2).
  
  **/
  UINTN
  EFIAPI
  AsmWriteDr2 (
    UINTN  Dr2
    );
  
  
  /**
    Writes a value to Debug Register 3 (DR3).
  
    Writes and returns a new value to DR3. This function is only available on
    IA-32 and x64. This writes a 32-bit value on IA-32 and a 64-bit value on x64.
  
    @param  Dr3 The value to write to Dr3.
  
    @return The value written to Debug Register 3 (DR3).
  
  **/
  UINTN
  EFIAPI
  AsmWriteDr3 (
    UINTN  Dr3
    );
  
  
  /**
    Writes a value to Debug Register 4 (DR4).
  
    Writes and returns a new value to DR4. This function is only available on
    IA-32 and x64. This writes a 32-bit value on IA-32 and a 64-bit value on x64.
  
    @param  Dr4 The value to write to Dr4.
  
    @return The value written to Debug Register 4 (DR4).
  
  **/
  UINTN
  EFIAPI
  AsmWriteDr4 (
    UINTN  Dr4
    );
  
  
  /**
    Writes a value to Debug Register 5 (DR5).
  
    Writes and returns a new value to DR5. This function is only available on
    IA-32 and x64. This writes a 32-bit value on IA-32 and a 64-bit value on x64.
  
    @param  Dr5 The value to write to Dr5.
  
    @return The value written to Debug Register 5 (DR5).
  
  **/
  UINTN
  EFIAPI
  AsmWriteDr5 (
    UINTN  Dr5
    );
  
  
  /**
    Writes a value to Debug Register 6 (DR6).
  
    Writes and returns a new value to DR6. This function is only available on
    IA-32 and x64. This writes a 32-bit value on IA-32 and a 64-bit value on x64.
  
    @param  Dr6 The value to write to Dr6.
  
    @return The value written to Debug Register 6 (DR6).
  
  **/
  UINTN
  EFIAPI
  AsmWriteDr6 (
    UINTN  Dr6
    );
  
  
  /**
    Writes a value to Debug Register 7 (DR7).
  
    Writes and returns a new value to DR7. This function is only available on
    IA-32 and x64. This writes a 32-bit value on IA-32 and a 64-bit value on x64.
  
    @param  Dr7 The value to write to Dr7.
  
    @return The value written to Debug Register 7 (DR7).
  
  **/
  UINTN
  EFIAPI
  AsmWriteDr7 (
    UINTN  Dr7
    );
  
  
  /**
    Reads the current value of Code Segment Register (CS).
  
    Reads and returns the current value of CS. This function is only available on
    IA-32 and x64.
  
    @return The current value of CS.
  
  **/
  UINT16
  EFIAPI
  AsmReadCs (
    VOID
    );
  
  
  /**
    Reads the current value of Data Segment Register (DS).
  
    Reads and returns the current value of DS. This function is only available on
    IA-32 and x64.
  
    @return The current value of DS.
  
  **/
  UINT16
  EFIAPI
  AsmReadDs (
    VOID
    );
  
  
  /**
    Reads the current value of Extra Segment Register (ES).
  
    Reads and returns the current value of ES. This function is only available on
    IA-32 and x64.
  
    @return The current value of ES.
  
  **/
  UINT16
  EFIAPI
  AsmReadEs (
    VOID
    );
  
  
  /**
    Reads the current value of FS Data Segment Register (FS).
  
    Reads and returns the current value of FS. This function is only available on
    IA-32 and x64.
  
    @return The current value of FS.
  
  **/
  UINT16
  EFIAPI
  AsmReadFs (
    VOID
    );
  
  
  /**
    Reads the current value of GS Data Segment Register (GS).
  
    Reads and returns the current value of GS. This function is only available on
    IA-32 and x64.
  
    @return The current value of GS.
  
  **/
  UINT16
  EFIAPI
  AsmReadGs (
    VOID
    );
  
  
  /**
    Reads the current value of Stack Segment Register (SS).
  
    Reads and returns the current value of SS. This function is only available on
    IA-32 and x64.
  
    @return The current value of SS.
  
  **/
  UINT16
  EFIAPI
  AsmReadSs (
    VOID
    );
  
  
  /**
    Reads the current value of Task Register (TR).
  
    Reads and returns the current value of TR. This function is only available on
    IA-32 and x64.
  
    @return The current value of TR.
  
  **/
  UINT16
  EFIAPI
  AsmReadTr (
    VOID
    );
  
  
  /**
    Reads the current Global Descriptor Table Register(GDTR) descriptor.
  
    Reads and returns the current GDTR descriptor and returns it in Gdtr. This
    function is only available on IA-32 and x64.
  
    If Gdtr is NULL, then ASSERT().
  
    @param  Gdtr  The pointer to a GDTR descriptor.
  
  **/
  VOID
  EFIAPI
  AsmReadGdtr (
    OUT     IA32_DESCRIPTOR           *Gdtr
    );
  
  
  /**
    Writes the current Global Descriptor Table Register (GDTR) descriptor.
  
    Writes and the current GDTR descriptor specified by Gdtr. This function is
    only available on IA-32 and x64.
  
    If Gdtr is NULL, then ASSERT().
  
    @param  Gdtr  The pointer to a GDTR descriptor.
  
  **/
  VOID
  EFIAPI
  AsmWriteGdtr (
    IN      CONST IA32_DESCRIPTOR     *Gdtr
    );
  
  
  /**
    Reads the current Interrupt Descriptor Table Register(IDTR) descriptor.
  
    Reads and returns the current IDTR descriptor and returns it in Idtr. This
    function is only available on IA-32 and x64.
  
    If Idtr is NULL, then ASSERT().
  
    @param  Idtr  The pointer to a IDTR descriptor.
  
  **/
  VOID
  EFIAPI
  AsmReadIdtr (
    OUT     IA32_DESCRIPTOR           *Idtr
    );
  
  
  /**
    Writes the current Interrupt Descriptor Table Register(IDTR) descriptor.
  
    Writes the current IDTR descriptor and returns it in Idtr. This function is
    only available on IA-32 and x64.
  
    If Idtr is NULL, then ASSERT().
  
    @param  Idtr  The pointer to a IDTR descriptor.
  
  **/
  VOID
  EFIAPI
  AsmWriteIdtr (
    IN      CONST IA32_DESCRIPTOR     *Idtr
    );
  
  
  /**
    Reads the current Local Descriptor Table Register(LDTR) selector.
  
    Reads and returns the current 16-bit LDTR descriptor value. This function is
    only available on IA-32 and x64.
  
    @return The current selector of LDT.
  
  **/
  UINT16
  EFIAPI
  AsmReadLdtr (
    VOID
    );
  
  
  /**
    Writes the current Local Descriptor Table Register (LDTR) selector.
  
    Writes and the current LDTR descriptor specified by Ldtr. This function is
    only available on IA-32 and x64.
  
    @param  Ldtr  16-bit LDTR selector value.
  
  **/
  VOID
  EFIAPI
  AsmWriteLdtr (
    IN      UINT16                    Ldtr
    );
  
  
  /**
    Save the current floating point/SSE/SSE2 context to a buffer.
  
    Saves the current floating point/SSE/SSE2 state to the buffer specified by
    Buffer. Buffer must be aligned on a 16-byte boundary. This function is only
    available on IA-32 and x64.
  
    If Buffer is NULL, then ASSERT().
    If Buffer is not aligned on a 16-byte boundary, then ASSERT().
  
    @param  Buffer  The pointer to a buffer to save the floating point/SSE/SSE2 context.
  
  **/
  VOID
  EFIAPI
  AsmFxSave (
    OUT     IA32_FX_BUFFER            *Buffer
    );
  
  
  /**
    Restores the current floating point/SSE/SSE2 context from a buffer.
  
    Restores the current floating point/SSE/SSE2 state from the buffer specified
    by Buffer. Buffer must be aligned on a 16-byte boundary. This function is
    only available on IA-32 and x64.
  
    If Buffer is NULL, then ASSERT().
    If Buffer is not aligned on a 16-byte boundary, then ASSERT().
    If Buffer was not saved with AsmFxSave(), then ASSERT().
  
    @param  Buffer  The pointer to a buffer to save the floating point/SSE/SSE2 context.
  
  **/
  VOID
  EFIAPI
  AsmFxRestore (
    IN      CONST IA32_FX_BUFFER      *Buffer
    );
  
  
  /**
    Reads the current value of 64-bit MMX Register #0 (MM0).
  
    Reads and returns the current value of MM0. This function is only available
    on IA-32 and x64.
  
    @return The current value of MM0.
  
  **/
  UINT64
  EFIAPI
  AsmReadMm0 (
    VOID
    );
  
  
  /**
    Reads the current value of 64-bit MMX Register #1 (MM1).
  
    Reads and returns the current value of MM1. This function is only available
    on IA-32 and x64.
  
    @return The current value of MM1.
  
  **/
  UINT64
  EFIAPI
  AsmReadMm1 (
    VOID
    );
  
  
  /**
    Reads the current value of 64-bit MMX Register #2 (MM2).
  
    Reads and returns the current value of MM2. This function is only available
    on IA-32 and x64.
  
    @return The current value of MM2.
  
  **/
  UINT64
  EFIAPI
  AsmReadMm2 (
    VOID
    );
  
  
  /**
    Reads the current value of 64-bit MMX Register #3 (MM3).
  
    Reads and returns the current value of MM3. This function is only available
    on IA-32 and x64.
  
    @return The current value of MM3.
  
  **/
  UINT64
  EFIAPI
  AsmReadMm3 (
    VOID
    );
  
  
  /**
    Reads the current value of 64-bit MMX Register #4 (MM4).
  
    Reads and returns the current value of MM4. This function is only available
    on IA-32 and x64.
  
    @return The current value of MM4.
  
  **/
  UINT64
  EFIAPI
  AsmReadMm4 (
    VOID
    );
  
  
  /**
    Reads the current value of 64-bit MMX Register #5 (MM5).
  
    Reads and returns the current value of MM5. This function is only available
    on IA-32 and x64.
  
    @return The current value of MM5.
  
  **/
  UINT64
  EFIAPI
  AsmReadMm5 (
    VOID
    );
  
  
  /**
    Reads the current value of 64-bit MMX Register #6 (MM6).
  
    Reads and returns the current value of MM6. This function is only available
    on IA-32 and x64.
  
    @return The current value of MM6.
  
  **/
  UINT64
  EFIAPI
  AsmReadMm6 (
    VOID
    );
  
  
  /**
    Reads the current value of 64-bit MMX Register #7 (MM7).
  
    Reads and returns the current value of MM7. This function is only available
    on IA-32 and x64.
  
    @return The current value of MM7.
  
  **/
  UINT64
  EFIAPI
  AsmReadMm7 (
    VOID
    );
  
  
  /**
    Writes the current value of 64-bit MMX Register #0 (MM0).
  
    Writes the current value of MM0. This function is only available on IA32 and
    x64.
  
    @param  Value The 64-bit value to write to MM0.
  
  **/
  VOID
  EFIAPI
  AsmWriteMm0 (
    IN      UINT64                    Value
    );
  
  
  /**
    Writes the current value of 64-bit MMX Register #1 (MM1).
  
    Writes the current value of MM1. This function is only available on IA32 and
    x64.
  
    @param  Value The 64-bit value to write to MM1.
  
  **/
  VOID
  EFIAPI
  AsmWriteMm1 (
    IN      UINT64                    Value
    );
  
  
  /**
    Writes the current value of 64-bit MMX Register #2 (MM2).
  
    Writes the current value of MM2. This function is only available on IA32 and
    x64.
  
    @param  Value The 64-bit value to write to MM2.
  
  **/
  VOID
  EFIAPI
  AsmWriteMm2 (
    IN      UINT64                    Value
    );
  
  
  /**
    Writes the current value of 64-bit MMX Register #3 (MM3).
  
    Writes the current value of MM3. This function is only available on IA32 and
    x64.
  
    @param  Value The 64-bit value to write to MM3.
  
  **/
  VOID
  EFIAPI
  AsmWriteMm3 (
    IN      UINT64                    Value
    );
  
  
  /**
    Writes the current value of 64-bit MMX Register #4 (MM4).
  
    Writes the current value of MM4. This function is only available on IA32 and
    x64.
  
    @param  Value The 64-bit value to write to MM4.
  
  **/
  VOID
  EFIAPI
  AsmWriteMm4 (
    IN      UINT64                    Value
    );
  
  
  /**
    Writes the current value of 64-bit MMX Register #5 (MM5).
  
    Writes the current value of MM5. This function is only available on IA32 and
    x64.
  
    @param  Value The 64-bit value to write to MM5.
  
  **/
  VOID
  EFIAPI
  AsmWriteMm5 (
    IN      UINT64                    Value
    );
  
  
  /**
    Writes the current value of 64-bit MMX Register #6 (MM6).
  
    Writes the current value of MM6. This function is only available on IA32 and
    x64.
  
    @param  Value The 64-bit value to write to MM6.
  
  **/
  VOID
  EFIAPI
  AsmWriteMm6 (
    IN      UINT64                    Value
    );
  
  
  /**
    Writes the current value of 64-bit MMX Register #7 (MM7).
  
    Writes the current value of MM7. This function is only available on IA32 and
    x64.
  
    @param  Value The 64-bit value to write to MM7.
  
  **/
  VOID
  EFIAPI
  AsmWriteMm7 (
    IN      UINT64                    Value
    );
  
  
  /**
    Reads the current value of Time Stamp Counter (TSC).
  
    Reads and returns the current value of TSC. This function is only available
    on IA-32 and x64.
  
    @return The current value of TSC
  
  **/
  UINT64
  EFIAPI
  AsmReadTsc (
    VOID
    );
  
  
  /**
    Reads the current value of a Performance Counter (PMC).
  
    Reads and returns the current value of performance counter specified by
    Index. This function is only available on IA-32 and x64.
  
    @param  Index The 32-bit Performance Counter index to read.
  
    @return The value of the PMC specified by Index.
  
  **/
  UINT64
  EFIAPI
  AsmReadPmc (
    IN      UINT32                    Index
    );
  
  
  /**
    Sets up a monitor buffer that is used by AsmMwait().
  
    Executes a MONITOR instruction with the register state specified by Eax, Ecx
    and Edx. Returns Eax. This function is only available on IA-32 and x64.
  
    @param  Eax The value to load into EAX or RAX before executing the MONITOR
                instruction.
    @param  Ecx The value to load into ECX or RCX before executing the MONITOR
                instruction.
    @param  Edx The value to load into EDX or RDX before executing the MONITOR
                instruction.
  
    @return Eax
  
  **/
  UINTN
  EFIAPI
  AsmMonitor (
    IN      UINTN                     Eax,
    IN      UINTN                     Ecx,
    IN      UINTN                     Edx
    );
  
  
  /**
    Executes an MWAIT instruction.
  
    Executes an MWAIT instruction with the register state specified by Eax and
    Ecx. Returns Eax. This function is only available on IA-32 and x64.
  
    @param  Eax The value to load into EAX or RAX before executing the MONITOR
                instruction.
    @param  Ecx The value to load into ECX or RCX before executing the MONITOR
                instruction.
  
    @return Eax
  
  **/
  UINTN
  EFIAPI
  AsmMwait (
    IN      UINTN                     Eax,
    IN      UINTN                     Ecx
    );
  
  
  /**
    Executes a WBINVD instruction.
  
    Executes a WBINVD instruction. This function is only available on IA-32 and
    x64.
  
  **/
  VOID
  EFIAPI
  AsmWbinvd (
    VOID
    );
  
  
  /**
    Executes a INVD instruction.
  
    Executes a INVD instruction. This function is only available on IA-32 and
    x64.
  
  **/
  VOID
  EFIAPI
  AsmInvd (
    VOID
    );
  
  
  /**
    Flushes a cache line from all the instruction and data caches within the
    coherency domain of the CPU.
  
    Flushed the cache line specified by LinearAddress, and returns LinearAddress.
    This function is only available on IA-32 and x64.
  
    @param  LinearAddress The address of the cache line to flush. If the CPU is
                          in a physical addressing mode, then LinearAddress is a
                          physical address. If the CPU is in a virtual
                          addressing mode, then LinearAddress is a virtual
                          address.
  
    @return LinearAddress.
  **/
  VOID *
  EFIAPI
  AsmFlushCacheLine (
    IN      VOID                      *LinearAddress
    );
  
  
  /**
    Enables the 32-bit paging mode on the CPU.
  
    Enables the 32-bit paging mode on the CPU. CR0, CR3, CR4, and the page tables
    must be properly initialized prior to calling this service. This function
    assumes the current execution mode is 32-bit protected mode. This function is
    only available on IA-32. After the 32-bit paging mode is enabled, control is
    transferred to the function specified by EntryPoint using the new stack
    specified by NewStack and passing in the parameters specified by Context1 and
    Context2. Context1 and Context2 are optional and may be NULL. The function
    EntryPoint must never return.
  
    If the current execution mode is not 32-bit protected mode, then ASSERT().
    If EntryPoint is NULL, then ASSERT().
    If NewStack is NULL, then ASSERT().
  
    There are a number of constraints that must be followed before calling this
    function:
    1)  Interrupts must be disabled.
    2)  The caller must be in 32-bit protected mode with flat descriptors. This
        means all descriptors must have a base of 0 and a limit of 4GB.
    3)  CR0 and CR4 must be compatible with 32-bit protected mode with flat
        descriptors.
    4)  CR3 must point to valid page tables that will be used once the transition
        is complete, and those page tables must guarantee that the pages for this
        function and the stack are identity mapped.
  
    @param  EntryPoint  A pointer to function to call with the new stack after
                        paging is enabled.
    @param  Context1    A pointer to the context to pass into the EntryPoint
                        function as the first parameter after paging is enabled.
    @param  Context2    A pointer to the context to pass into the EntryPoint
                        function as the second parameter after paging is enabled.
    @param  NewStack    A pointer to the new stack to use for the EntryPoint
                        function after paging is enabled.
  
  **/
  VOID
  EFIAPI
  AsmEnablePaging32 (
    IN      SWITCH_STACK_ENTRY_POINT  EntryPoint,
    IN      VOID                      *Context1,  OPTIONAL
    IN      VOID                      *Context2,  OPTIONAL
    IN      VOID                      *NewStack
    );
  
  
  /**
    Disables the 32-bit paging mode on the CPU.
  
    Disables the 32-bit paging mode on the CPU and returns to 32-bit protected
    mode. This function assumes the current execution mode is 32-paged protected
    mode. This function is only available on IA-32. After the 32-bit paging mode
    is disabled, control is transferred to the function specified by EntryPoint
    using the new stack specified by NewStack and passing in the parameters
    specified by Context1 and Context2. Context1 and Context2 are optional and
    may be NULL. The function EntryPoint must never return.
  
    If the current execution mode is not 32-bit paged mode, then ASSERT().
    If EntryPoint is NULL, then ASSERT().
    If NewStack is NULL, then ASSERT().
  
    There are a number of constraints that must be followed before calling this
    function:
    1)  Interrupts must be disabled.
    2)  The caller must be in 32-bit paged mode.
    3)  CR0, CR3, and CR4 must be compatible with 32-bit paged mode.
    4)  CR3 must point to valid page tables that guarantee that the pages for
        this function and the stack are identity mapped.
  
    @param  EntryPoint  A pointer to function to call with the new stack after
                        paging is disabled.
    @param  Context1    A pointer to the context to pass into the EntryPoint
                        function as the first parameter after paging is disabled.
    @param  Context2    A pointer to the context to pass into the EntryPoint
                        function as the second parameter after paging is
                        disabled.
    @param  NewStack    A pointer to the new stack to use for the EntryPoint
                        function after paging is disabled.
  
  **/
  VOID
  EFIAPI
  AsmDisablePaging32 (
    IN      SWITCH_STACK_ENTRY_POINT  EntryPoint,
    IN      VOID                      *Context1,  OPTIONAL
    IN      VOID                      *Context2,  OPTIONAL
    IN      VOID                      *NewStack
    );
  
  
  /**
    Enables the 64-bit paging mode on the CPU.
  
    Enables the 64-bit paging mode on the CPU. CR0, CR3, CR4, and the page tables
    must be properly initialized prior to calling this service. This function
    assumes the current execution mode is 32-bit protected mode with flat
    descriptors. This function is only available on IA-32. After the 64-bit
    paging mode is enabled, control is transferred to the function specified by
    EntryPoint using the new stack specified by NewStack and passing in the
    parameters specified by Context1 and Context2. Context1 and Context2 are
    optional and may be 0. The function EntryPoint must never return.
  
    If the current execution mode is not 32-bit protected mode with flat
    descriptors, then ASSERT().
    If EntryPoint is 0, then ASSERT().
    If NewStack is 0, then ASSERT().
  
    @param  Cs          The 16-bit selector to load in the CS before EntryPoint
                        is called. The descriptor in the GDT that this selector
                        references must be setup for long mode.
    @param  EntryPoint  The 64-bit virtual address of the function to call with
                        the new stack after paging is enabled.
    @param  Context1    The 64-bit virtual address of the context to pass into
                        the EntryPoint function as the first parameter after
                        paging is enabled.
    @param  Context2    The 64-bit virtual address of the context to pass into
                        the EntryPoint function as the second parameter after
                        paging is enabled.
    @param  NewStack    The 64-bit virtual address of the new stack to use for
                        the EntryPoint function after paging is enabled.
  
  **/
  VOID
  EFIAPI
  AsmEnablePaging64 (
    IN      UINT16                    Cs,
    IN      UINT64                    EntryPoint,
    IN      UINT64                    Context1,  OPTIONAL
    IN      UINT64                    Context2,  OPTIONAL
    IN      UINT64                    NewStack
    );
  
  
  /**
    Disables the 64-bit paging mode on the CPU.
  
    Disables the 64-bit paging mode on the CPU and returns to 32-bit protected
    mode. This function assumes the current execution mode is 64-paging mode.
    This function is only available on x64. After the 64-bit paging mode is
    disabled, control is transferred to the function specified by EntryPoint
    using the new stack specified by NewStack and passing in the parameters
    specified by Context1 and Context2. Context1 and Context2 are optional and
    may be 0. The function EntryPoint must never return.
  
    If the current execution mode is not 64-bit paged mode, then ASSERT().
    If EntryPoint is 0, then ASSERT().
    If NewStack is 0, then ASSERT().
  
    @param  Cs          The 16-bit selector to load in the CS before EntryPoint
                        is called. The descriptor in the GDT that this selector
                        references must be setup for 32-bit protected mode.
    @param  EntryPoint  The 64-bit virtual address of the function to call with
                        the new stack after paging is disabled.
    @param  Context1    The 64-bit virtual address of the context to pass into
                        the EntryPoint function as the first parameter after
                        paging is disabled.
    @param  Context2    The 64-bit virtual address of the context to pass into
                        the EntryPoint function as the second parameter after
                        paging is disabled.
    @param  NewStack    The 64-bit virtual address of the new stack to use for
                        the EntryPoint function after paging is disabled.
  
  **/
  VOID
  EFIAPI
  AsmDisablePaging64 (
    IN      UINT16                    Cs,
    IN      UINT32                    EntryPoint,
    IN      UINT32                    Context1,  OPTIONAL
    IN      UINT32                    Context2,  OPTIONAL
    IN      UINT32                    NewStack
    );
  
  
  //
  // 16-bit thunking services
  //
  
  /**
    Retrieves the properties for 16-bit thunk functions.
  
    Computes the size of the buffer and stack below 1MB required to use the
    AsmPrepareThunk16(), AsmThunk16() and AsmPrepareAndThunk16() functions. This
    buffer size is returned in RealModeBufferSize, and the stack size is returned
    in ExtraStackSize. If parameters are passed to the 16-bit real mode code,
    then the actual minimum stack size is ExtraStackSize plus the maximum number
    of bytes that need to be passed to the 16-bit real mode code.
  
    If RealModeBufferSize is NULL, then ASSERT().
    If ExtraStackSize is NULL, then ASSERT().
  
    @param  RealModeBufferSize  A pointer to the size of the buffer below 1MB
                                required to use the 16-bit thunk functions.
    @param  ExtraStackSize      A pointer to the extra size of stack below 1MB
                                that the 16-bit thunk functions require for
                                temporary storage in the transition to and from
                                16-bit real mode.
  
  **/
  VOID
  EFIAPI
  AsmGetThunk16Properties (
    OUT     UINT32                    *RealModeBufferSize,
    OUT     UINT32                    *ExtraStackSize
    );
  
  
  /**
    Prepares all structures a code required to use AsmThunk16().
  
    Prepares all structures and code required to use AsmThunk16().
  
    This interface is limited to be used in either physical mode or virtual modes with paging enabled where the
    virtual to physical mappings for ThunkContext.RealModeBuffer is mapped 1:1.
  
    If ThunkContext is NULL, then ASSERT().
  
    @param  ThunkContext  A pointer to the context structure that describes the
                          16-bit real mode code to call.
  
  **/
  VOID
  EFIAPI
  AsmPrepareThunk16 (
    IN OUT  THUNK_CONTEXT             *ThunkContext
    );
  
  
  /**
    Transfers control to a 16-bit real mode entry point and returns the results.
  
    Transfers control to a 16-bit real mode entry point and returns the results.
    AsmPrepareThunk16() must be called with ThunkContext before this function is used.
    This function must be called with interrupts disabled.
  
    The register state from the RealModeState field of ThunkContext is restored just prior
    to calling the 16-bit real mode entry point.  This includes the EFLAGS field of RealModeState,
    which is used to set the interrupt state when a 16-bit real mode entry point is called.
    Control is transferred to the 16-bit real mode entry point specified by the CS and Eip fields of RealModeState.
    The stack is initialized to the SS and ESP fields of RealModeState.  Any parameters passed to
    the 16-bit real mode code must be populated by the caller at SS:ESP prior to calling this function.
    The 16-bit real mode entry point is invoked with a 16-bit CALL FAR instruction,
    so when accessing stack contents, the 16-bit real mode code must account for the 16-bit segment
    and 16-bit offset of the return address that were pushed onto the stack. The 16-bit real mode entry
    point must exit with a RETF instruction. The register state is captured into RealModeState immediately
    after the RETF instruction is executed.
  
    If EFLAGS specifies interrupts enabled, or any of the 16-bit real mode code enables interrupts,
    or any of the 16-bit real mode code makes a SW interrupt, then the caller is responsible for making sure
    the IDT at address 0 is initialized to handle any HW or SW interrupts that may occur while in 16-bit real mode.
  
    If EFLAGS specifies interrupts enabled, or any of the 16-bit real mode code enables interrupts,
    then the caller is responsible for making sure the 8259 PIC is in a state compatible with 16-bit real mode.
    This includes the base vectors, the interrupt masks, and the edge/level trigger mode.
  
    If THUNK_ATTRIBUTE_BIG_REAL_MODE is set in the ThunkAttributes field of ThunkContext, then the user code
    is invoked in big real mode.  Otherwise, the user code is invoked in 16-bit real mode with 64KB segment limits.
  
    If neither THUNK_ATTRIBUTE_DISABLE_A20_MASK_INT_15 nor THUNK_ATTRIBUTE_DISABLE_A20_MASK_KBD_CTRL are set in
    ThunkAttributes, then it is assumed that the user code did not enable the A20 mask, and no attempt is made to
    disable the A20 mask.
  
    If THUNK_ATTRIBUTE_DISABLE_A20_MASK_INT_15 is set and THUNK_ATTRIBUTE_DISABLE_A20_MASK_KBD_CTRL is clear in
    ThunkAttributes, then attempt to use the INT 15 service to disable the A20 mask.  If this INT 15 call fails,
    then attempt to disable the A20 mask by directly accessing the 8042 keyboard controller I/O ports.
  
    If THUNK_ATTRIBUTE_DISABLE_A20_MASK_INT_15 is clear and THUNK_ATTRIBUTE_DISABLE_A20_MASK_KBD_CTRL is set in
    ThunkAttributes, then attempt to disable the A20 mask by directly accessing the 8042 keyboard controller I/O ports.
  
    If ThunkContext is NULL, then ASSERT().
    If AsmPrepareThunk16() was not previously called with ThunkContext, then ASSERT().
    If both THUNK_ATTRIBUTE_DISABLE_A20_MASK_INT_15 and THUNK_ATTRIBUTE_DISABLE_A20_MASK_KBD_CTRL are set in
    ThunkAttributes, then ASSERT().
  
    This interface is limited to be used in either physical mode or virtual modes with paging enabled where the
    virtual to physical mappings for ThunkContext.RealModeBuffer are mapped 1:1.
  
    @param  ThunkContext  A pointer to the context structure that describes the
                          16-bit real mode code to call.
  
  **/
  VOID
  EFIAPI
  AsmThunk16 (
    IN OUT  THUNK_CONTEXT             *ThunkContext
    );
  
  
  /**
    Prepares all structures and code for a 16-bit real mode thunk, transfers
    control to a 16-bit real mode entry point, and returns the results.
  
    Prepares all structures and code for a 16-bit real mode thunk, transfers
    control to a 16-bit real mode entry point, and returns the results. If the
    caller only need to perform a single 16-bit real mode thunk, then this
    service should be used. If the caller intends to make more than one 16-bit
    real mode thunk, then it is more efficient if AsmPrepareThunk16() is called
    once and AsmThunk16() can be called for each 16-bit real mode thunk.
  
    This interface is limited to be used in either physical mode or virtual modes with paging enabled where the
    virtual to physical mappings for ThunkContext.RealModeBuffer is mapped 1:1.
  
    See AsmPrepareThunk16() and AsmThunk16() for the detailed description and ASSERT() conditions.
  
    @param  ThunkContext  A pointer to the context structure that describes the
                          16-bit real mode code to call.
  
  **/
  VOID
  EFIAPI
  AsmPrepareAndThunk16 (
    IN OUT  THUNK_CONTEXT             *ThunkContext
    );
  
  /**
    Generates a 16-bit random number through RDRAND instruction.
  
    if Rand is NULL, then ASSERT().
  
    @param[out]  Rand     Buffer pointer to store the random result.
  
    @retval TRUE          RDRAND call was successful.
    @retval FALSE         Failed attempts to call RDRAND.
  
   **/
  BOOLEAN
  EFIAPI
  AsmRdRand16 (
    OUT     UINT16                    *Rand
    );
  
  /**
    Generates a 32-bit random number through RDRAND instruction.
  
    if Rand is NULL, then ASSERT().
  
    @param[out]  Rand     Buffer pointer to store the random result.
  
    @retval TRUE          RDRAND call was successful.
    @retval FALSE         Failed attempts to call RDRAND.
  
  **/
  BOOLEAN
  EFIAPI
  AsmRdRand32 (
    OUT     UINT32                    *Rand
    );
  
  /**
    Generates a 64-bit random number through RDRAND instruction.
  
    if Rand is NULL, then ASSERT().
  
    @param[out]  Rand     Buffer pointer to store the random result.
  
    @retval TRUE          RDRAND call was successful.
    @retval FALSE         Failed attempts to call RDRAND.
  
  **/
  BOOLEAN
  EFIAPI
  AsmRdRand64  (
    OUT     UINT64                    *Rand
    );
  
  /**
    Load given selector into TR register.
  
    @param[in] Selector     Task segment selector
  **/
  VOID
  EFIAPI
  AsmWriteTr (
    IN UINT16 Selector
    );
  
  /**
    Performs a serializing operation on all load-from-memory instructions that
    were issued prior the AsmLfence function.
  
    Executes a LFENCE instruction. This function is only available on IA-32 and x64.
  
  **/
  VOID
  EFIAPI
  AsmLfence (
    VOID
    );
  
  /**
    Patch the immediate operand of an IA32 or X64 instruction such that the byte,
    word, dword or qword operand is encoded at the end of the instruction's
    binary representation.
  
    This function should be used to update object code that was compiled with
    NASM from assembly source code. Example:
  
    NASM source code:
  
          mov     eax, strict dword 0 ; the imm32 zero operand will be patched
      ASM_PFX(gPatchCr3):
          mov     cr3, eax
  
    C source code:
  
      X86_ASSEMBLY_PATCH_LABEL gPatchCr3;
      PatchInstructionX86 (gPatchCr3, AsmReadCr3 (), 4);
  
    @param[out] InstructionEnd  Pointer right past the instruction to patch. The
                                immediate operand to patch is expected to
                                comprise the trailing bytes of the instruction.
                                If InstructionEnd is closer to address 0 than
                                ValueSize permits, then ASSERT().
  
    @param[in] PatchValue       The constant to write to the immediate operand.
                                The caller is responsible for ensuring that
                                PatchValue can be represented in the byte, word,
                                dword or qword operand (as indicated through
                                ValueSize); otherwise ASSERT().
  
    @param[in] ValueSize        The size of the operand in bytes; must be 1, 2,
                                4, or 8. ASSERT() otherwise.
  **/
  VOID
  EFIAPI
  PatchInstructionX86 (
    OUT X86_ASSEMBLY_PATCH_LABEL *InstructionEnd,
    IN  UINT64                   PatchValue,
    IN  UINTN                    ValueSize
    );
  
  #endif // defined (MDE_CPU_IA32) || defined (MDE_CPU_X64)
  #endif // !defined (__BASE_LIB__)