FreeBSD/Linux Kernel Cross Reference
sys/contrib/dev/acpica/compiler/aslxref.c

     /******************************************************************************
      *
      * Module Name: aslxref - Namespace cross-reference
      *
      *****************************************************************************/
     
     /******************************************************************************
      *
      * 1. Copyright Notice
     *
     * Some or all of this work - Copyright (c) 1999 - 2022, Intel Corp.
     * All rights reserved.
     *
     * 2. License
     *
     * 2.1. This is your license from Intel Corp. under its intellectual property
     * rights. You may have additional license terms from the party that provided
     * you this software, covering your right to use that party's intellectual
     * property rights.
     *
     * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a
     * copy of the source code appearing in this file ("Covered Code") an
     * irrevocable, perpetual, worldwide license under Intel's copyrights in the
     * base code distributed originally by Intel ("Original Intel Code") to copy,
     * make derivatives, distribute, use and display any portion of the Covered
     * Code in any form, with the right to sublicense such rights; and
     *
     * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent
     * license (with the right to sublicense), under only those claims of Intel
     * patents that are infringed by the Original Intel Code, to make, use, sell,
     * offer to sell, and import the Covered Code and derivative works thereof
     * solely to the minimum extent necessary to exercise the above copyright
     * license, and in no event shall the patent license extend to any additions
     * to or modifications of the Original Intel Code. No other license or right
     * is granted directly or by implication, estoppel or otherwise;
     *
     * The above copyright and patent license is granted only if the following
     * conditions are met:
     *
     * 3. Conditions
     *
     * 3.1. Redistribution of Source with Rights to Further Distribute Source.
     * Redistribution of source code of any substantial portion of the Covered
     * Code or modification with rights to further distribute source must include
     * the above Copyright Notice, the above License, this list of Conditions,
     * and the following Disclaimer and Export Compliance provision. In addition,
     * Licensee must cause all Covered Code to which Licensee contributes to
     * contain a file documenting the changes Licensee made to create that Covered
     * Code and the date of any change. Licensee must include in that file the
     * documentation of any changes made by any predecessor Licensee. Licensee
     * must include a prominent statement that the modification is derived,
     * directly or indirectly, from Original Intel Code.
     *
     * 3.2. Redistribution of Source with no Rights to Further Distribute Source.
     * Redistribution of source code of any substantial portion of the Covered
     * Code or modification without rights to further distribute source must
     * include the following Disclaimer and Export Compliance provision in the
     * documentation and/or other materials provided with distribution. In
     * addition, Licensee may not authorize further sublicense of source of any
     * portion of the Covered Code, and must include terms to the effect that the
     * license from Licensee to its licensee is limited to the intellectual
     * property embodied in the software Licensee provides to its licensee, and
     * not to intellectual property embodied in modifications its licensee may
     * make.
     *
     * 3.3. Redistribution of Executable. Redistribution in executable form of any
     * substantial portion of the Covered Code or modification must reproduce the
     * above Copyright Notice, and the following Disclaimer and Export Compliance
     * provision in the documentation and/or other materials provided with the
     * distribution.
     *
     * 3.4. Intel retains all right, title, and interest in and to the Original
     * Intel Code.
     *
     * 3.5. Neither the name Intel nor any other trademark owned or controlled by
     * Intel shall be used in advertising or otherwise to promote the sale, use or
     * other dealings in products derived from or relating to the Covered Code
     * without prior written authorization from Intel.
     *
     * 4. Disclaimer and Export Compliance
     *
     * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED
     * HERE. ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE
     * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT, ASSISTANCE,
     * INSTALLATION, TRAINING OR OTHER SERVICES. INTEL WILL NOT PROVIDE ANY
     * UPDATES, ENHANCEMENTS OR EXTENSIONS. INTEL SPECIFICALLY DISCLAIMS ANY
     * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A
     * PARTICULAR PURPOSE.
     *
     * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES
     * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR
     * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,
     * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY
     * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL
     * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES. THESE LIMITATIONS
     * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY
     * LIMITED REMEDY.
     *
     * 4.3. Licensee shall not export, either directly or indirectly, any of this
    * software or system incorporating such software without first obtaining any
    * required license or other approval from the U. S. Department of Commerce or
    * any other agency or department of the United States Government. In the
    * event Licensee exports any such software from the United States or
    * re-exports any such software from a foreign destination, Licensee shall
    * ensure that the distribution and export/re-export of the software is in
    * compliance with all laws, regulations, orders, or other restrictions of the
    * U.S. Export Administration Regulations. Licensee agrees that neither it nor
    * any of its subsidiaries will export/re-export any technical data, process,
    * software, or service, directly or indirectly, to any country for which the
    * United States government or any agency thereof requires an export license,
    * other governmental approval, or letter of assurance, without first obtaining
    * such license, approval or letter.
    *
    *****************************************************************************
    *
    * Alternatively, you may choose to be licensed under the terms of the
    * following license:
    *
    * Redistribution and use in source and binary forms, with or without
    * modification, are permitted provided that the following conditions
    * are met:
    * 1. Redistributions of source code must retain the above copyright
    *    notice, this list of conditions, and the following disclaimer,
    *    without modification.
    * 2. Redistributions in binary form must reproduce at minimum a disclaimer
    *    substantially similar to the "NO WARRANTY" disclaimer below
    *    ("Disclaimer") and any redistribution must be conditioned upon
    *    including a substantially similar Disclaimer requirement for further
    *    binary redistribution.
    * 3. Neither the names of the above-listed copyright holders nor the names
    *    of any contributors may be used to endorse or promote products derived
    *    from this software without specific prior written permission.
    *
    * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
    * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
    * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
    * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
    * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
    * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
    * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
    * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
    * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
    * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
    * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
    *
    * Alternatively, you may choose to be licensed under the terms of the
    * GNU General Public License ("GPL") version 2 as published by the Free
    * Software Foundation.
    *
    *****************************************************************************/
   
   #include <contrib/dev/acpica/compiler/aslcompiler.h>
   #include "aslcompiler.y.h"
   #include <contrib/dev/acpica/include/acparser.h>
   #include <contrib/dev/acpica/include/amlcode.h>
   #include <contrib/dev/acpica/include/acnamesp.h>
   #include <contrib/dev/acpica/include/acdispat.h>
   
   
   #define _COMPONENT          ACPI_COMPILER
           ACPI_MODULE_NAME    ("aslxref")
   
   /* Local prototypes */
   
   static ACPI_STATUS
   XfNamespaceLocateBegin (
       ACPI_PARSE_OBJECT       *Op,
       UINT32                  Level,
       void                    *Context);
   
   static ACPI_STATUS
   XfNamespaceLocateEnd (
       ACPI_PARSE_OBJECT       *Op,
       UINT32                  Level,
       void                    *Context);
   
   static BOOLEAN
   XfValidateCrossReference (
       ACPI_PARSE_OBJECT       *Op,
       const ACPI_OPCODE_INFO  *OpInfo,
       ACPI_NAMESPACE_NODE     *Node);
   
   static BOOLEAN
   XfObjectExists (
       char                    *Name);
   
   static ACPI_STATUS
   XfCompareOneNamespaceObject (
       ACPI_HANDLE             ObjHandle,
       UINT32                  Level,
       void                    *Context,
       void                    **ReturnValue);
   
   static void
   XfCheckFieldRange (
       ACPI_PARSE_OBJECT       *Op,
       UINT32                  RegionBitLength,
       UINT32                  FieldBitOffset,
       UINT32                  FieldBitLength,
       UINT32                  AccessBitWidth);
   
   static BOOLEAN
   XfFindCondRefOfName (
       ACPI_NAMESPACE_NODE     *Node,
       ACPI_PARSE_OBJECT       *Op);
   
   static BOOLEAN
   XfRefIsGuardedByIfCondRefOf (
       ACPI_NAMESPACE_NODE     *Node,
       ACPI_PARSE_OBJECT       *Op);
   
   
   /*******************************************************************************
    *
    * FUNCTION:    XfCrossReferenceNamespace
    *
    * PARAMETERS:  None
    *
    * RETURN:      Status
    *
    * DESCRIPTION: Perform a cross reference check of the parse tree against the
    *              namespace. Every named referenced within the parse tree
    *              should be get resolved with a namespace lookup. If not, the
    *              original reference in the ASL code is invalid -- i.e., refers
    *              to a non-existent object.
    *
    * NOTE:  The ASL "External" operator causes the name to be inserted into the
    *        namespace so that references to the external name will be resolved
    *        correctly here.
    *
    ******************************************************************************/
   
   ACPI_STATUS
   XfCrossReferenceNamespace (
       void)
   {
       ACPI_WALK_STATE         *WalkState;
   
   
       /*
        * Create a new walk state for use when looking up names
        * within the namespace (Passed as context to the callbacks)
        */
       WalkState = AcpiDsCreateWalkState (0, NULL, NULL, NULL);
       if (!WalkState)
       {
           return (AE_NO_MEMORY);
       }
   
       /* Walk the entire parse tree */
   
       TrWalkParseTree (AslGbl_ParseTreeRoot, ASL_WALK_VISIT_TWICE,
           XfNamespaceLocateBegin, XfNamespaceLocateEnd, WalkState);
   
       ACPI_FREE (WalkState);
       return (AE_OK);
   }
   
   
   /*******************************************************************************
    *
    * FUNCTION:    XfObjectExists
    *
    * PARAMETERS:  Name            - 4 char ACPI name
    *
    * RETURN:      TRUE if name exists in namespace
    *
    * DESCRIPTION: Walk the namespace to find an object
    *
    ******************************************************************************/
   
   static BOOLEAN
   XfObjectExists (
       char                    *Name)
   {
       ACPI_STATUS             Status;
   
   
       /* Walk entire namespace from the supplied root */
   
       Status = AcpiNsWalkNamespace (ACPI_TYPE_ANY, ACPI_ROOT_OBJECT,
           ACPI_UINT32_MAX, FALSE, XfCompareOneNamespaceObject, NULL,
           Name, NULL);
       if (Status == AE_CTRL_TRUE)
       {
           /* At least one instance of the name was found */
   
           return (TRUE);
       }
   
       return (FALSE);
   }
   
   
   /*******************************************************************************
    *
    * FUNCTION:    XfCompareOneNamespaceObject
    *
    * PARAMETERS:  ACPI_WALK_CALLBACK
    *
    * RETURN:      Status
    *
    * DESCRIPTION: Compare name of one object.
    *
    ******************************************************************************/
   
   static ACPI_STATUS
   XfCompareOneNamespaceObject (
       ACPI_HANDLE             ObjHandle,
       UINT32                  Level,
       void                    *Context,
       void                    **ReturnValue)
   {
       ACPI_NAMESPACE_NODE     *Node = (ACPI_NAMESPACE_NODE *) ObjHandle;
   
   
       /* Simply check the name */
   
       if (*((UINT32 *) (Context)) == Node->Name.Integer)
       {
           /* Abort walk if we found one instance */
   
           return (AE_CTRL_TRUE);
       }
   
       return (AE_OK);
   }
   
   
   /*******************************************************************************
    *
    * FUNCTION:    XfCheckFieldRange
    *
    * PARAMETERS:  RegionBitLength     - Length of entire parent region
    *              FieldBitOffset      - Start of the field unit (within region)
    *              FieldBitLength      - Entire length of field unit
    *              AccessBitWidth      - Access width of the field unit
    *
    * RETURN:      None
    *
    * DESCRIPTION: Check one field unit to make sure it fits in the parent
    *              op region.
    *
    * Note: AccessBitWidth must be either 8,16,32, or 64
    *
    ******************************************************************************/
   
   static void
   XfCheckFieldRange (
       ACPI_PARSE_OBJECT       *Op,
       UINT32                  RegionBitLength,
       UINT32                  FieldBitOffset,
       UINT32                  FieldBitLength,
       UINT32                  AccessBitWidth)
   {
       UINT32                  FieldEndBitOffset;
   
   
       /*
        * Check each field unit against the region size. The entire
        * field unit (start offset plus length) must fit within the
        * region.
        */
       FieldEndBitOffset = FieldBitOffset + FieldBitLength;
   
       if (FieldEndBitOffset > RegionBitLength)
       {
           /* Field definition itself is beyond the end-of-region */
   
           AslError (ASL_ERROR, ASL_MSG_FIELD_UNIT_OFFSET, Op, NULL);
           return;
       }
   
       /*
        * Now check that the field plus AccessWidth doesn't go beyond
        * the end-of-region. Assumes AccessBitWidth is a power of 2
        */
       FieldEndBitOffset = ACPI_ROUND_UP (FieldEndBitOffset, AccessBitWidth);
   
       if (FieldEndBitOffset > RegionBitLength)
       {
           /* Field definition combined with the access is beyond EOR */
   
           AslError (ASL_ERROR, ASL_MSG_FIELD_UNIT_ACCESS_WIDTH, Op, NULL);
       }
   }
   
   
   /*******************************************************************************
    *
    * FUNCTION:    XfNamespaceLocateBegin
    *
    * PARAMETERS:  ASL_WALK_CALLBACK
    *
    * RETURN:      Status
    *
    * DESCRIPTION: Descending callback used during cross-reference. For named
    *              object references, attempt to locate the name in the
    *              namespace.
    *
    * NOTE: ASL references to named fields within resource descriptors are
    *       resolved to integer values here. Therefore, this step is an
    *       important part of the code generation. We don't know that the
    *       name refers to a resource descriptor until now.
    *
    ******************************************************************************/
   
   static ACPI_STATUS
   XfNamespaceLocateBegin (
       ACPI_PARSE_OBJECT       *Op,
       UINT32                  Level,
       void                    *Context)
   {
       ACPI_WALK_STATE         *WalkState = (ACPI_WALK_STATE *) Context;
       ACPI_NAMESPACE_NODE     *Node;
       ACPI_STATUS             Status;
       ACPI_OBJECT_TYPE        ObjectType;
       char                    *Path;
       UINT8                   PassedArgs;
       ACPI_PARSE_OBJECT       *NextOp;
       ACPI_PARSE_OBJECT       *OwningOp;
       ACPI_PARSE_OBJECT       *SpaceIdOp;
       UINT32                  MinimumLength;
       UINT32                  Offset;
       UINT32                  FieldBitLength;
       UINT32                  TagBitLength;
       UINT8                   Message = 0;
       const ACPI_OPCODE_INFO  *OpInfo;
       UINT32                  Flags;
       ASL_METHOD_LOCAL        *MethodLocals = NULL;
       ASL_METHOD_LOCAL        *MethodArgs = NULL;
       int                     RegisterNumber;
       UINT32                  i;
       ACPI_NAMESPACE_NODE     *DeclarationParentMethod;
       ACPI_PARSE_OBJECT       *ReferenceParentMethod;
       char                    *ExternalPath;
   
   
       ACPI_FUNCTION_TRACE_PTR (XfNamespaceLocateBegin, Op);
   
   
       if ((Op->Asl.AmlOpcode == AML_METHOD_OP) && Op->Asl.Node)
       {
           Node = Op->Asl.Node;
   
           /* Support for method LocalX/ArgX analysis */
   
           if (!Node->MethodLocals)
           {
               /* Create local/arg info blocks */
   
               MethodLocals = UtLocalCalloc (
                   sizeof (ASL_METHOD_LOCAL) * ACPI_METHOD_NUM_LOCALS);
               Node->MethodLocals = MethodLocals;
   
               MethodArgs = UtLocalCalloc (
                   sizeof (ASL_METHOD_LOCAL) * ACPI_METHOD_NUM_ARGS);
               Node->MethodArgs = MethodArgs;
   
               /*
                * Get the method argument count
                * First, get the name node
                */
               NextOp = Op->Asl.Child;
   
               /* Get the NumArguments node */
   
               NextOp = NextOp->Asl.Next;
               Node->ArgCount = (UINT8)
                   (((UINT8) NextOp->Asl.Value.Integer) & 0x07);
   
               /* We will track all possible ArgXs */
   
               for (i = 0; i < ACPI_METHOD_NUM_ARGS; i++)
               {
                   if (i < Node->ArgCount)
                   {
                       /* Real Args are always "initialized" */
   
                       MethodArgs[i].Flags = ASL_ARG_INITIALIZED;
                   }
                   else
                   {
                       /* Other ArgXs can be used as locals */
   
                       MethodArgs[i].Flags = ASL_ARG_IS_LOCAL;
                   }
   
                   MethodArgs[i].Op = Op;
               }
           }
       }
   
       /*
        * If this node is the actual declaration of a name
        * [such as the XXXX name in "Method (XXXX)"],
        * we are not interested in it here. We only care about names that are
        * references to other objects within the namespace and the parent objects
        * of name declarations
        */
       if (Op->Asl.CompileFlags & OP_IS_NAME_DECLARATION)
       {
           return_ACPI_STATUS (AE_OK);
       }
   
       OpInfo = AcpiPsGetOpcodeInfo (Op->Asl.AmlOpcode);
   
       /* Check method LocalX variables */
   
       if (OpInfo->Type == AML_TYPE_LOCAL_VARIABLE)
       {
           /* Find parent method Op */
   
           NextOp = UtGetParentMethodOp (Op);
           if (!NextOp)
           {
               return_ACPI_STATUS (AE_OK);
           }
   
           /* Get method node */
   
           Node = NextOp->Asl.Node;
   
           RegisterNumber = Op->Asl.AmlOpcode & 0x0007; /* 0x60 through 0x67 */
           MethodLocals = Node->MethodLocals;
   
           if (Op->Asl.CompileFlags & OP_IS_TARGET)
           {
               /* Local is being initialized */
   
               MethodLocals[RegisterNumber].Flags |= ASL_LOCAL_INITIALIZED;
               MethodLocals[RegisterNumber].Op = Op;
   
               return_ACPI_STATUS (AE_OK);
           }
   
           /* Mark this Local as referenced */
   
           MethodLocals[RegisterNumber].Flags |= ASL_LOCAL_REFERENCED;
           MethodLocals[RegisterNumber].Op = Op;
   
           return_ACPI_STATUS (AE_OK);
       }
   
       /* Check method ArgX variables */
   
       if (OpInfo->Type == AML_TYPE_METHOD_ARGUMENT)
       {
           /* Find parent method Op */
   
           NextOp = UtGetParentMethodOp (Op);
           if (!NextOp)
           {
               return_ACPI_STATUS (AE_OK);
           }
   
           /* Get method node */
   
           Node = NextOp->Asl.Node;
   
           /* Get Arg # */
   
           RegisterNumber = Op->Asl.AmlOpcode - AML_ARG0; /* 0x68 through 0x6F */
           MethodArgs = Node->MethodArgs;
   
           /* Mark this Arg as referenced */
   
           MethodArgs[RegisterNumber].Flags |= ASL_ARG_REFERENCED;
           MethodArgs[RegisterNumber].Op = Op;
   
           if (Op->Asl.CompileFlags & OP_IS_TARGET)
           {
               /* Arg is being initialized */
   
               MethodArgs[RegisterNumber].Flags |= ASL_ARG_INITIALIZED;
           }
   
           return_ACPI_STATUS (AE_OK);
       }
   
       /*
        * After method ArgX and LocalX, we are only interested in opcodes
        * that have an associated name
        */
       if ((!(OpInfo->Flags & AML_NAMED)) &&
           (!(OpInfo->Flags & AML_CREATE)) &&
           (Op->Asl.ParseOpcode != PARSEOP_NAMESTRING) &&
           (Op->Asl.ParseOpcode != PARSEOP_NAMESEG)    &&
           (Op->Asl.ParseOpcode != PARSEOP_METHODCALL) &&
           (Op->Asl.ParseOpcode != PARSEOP_EXTERNAL))
       {
           return_ACPI_STATUS (AE_OK);
       }
   
       /*
        * We must enable the "search-to-root" for single NameSegs, but
        * we have to be very careful about opening up scopes
        */
       Flags = ACPI_NS_SEARCH_PARENT;
       if ((Op->Asl.ParseOpcode == PARSEOP_NAMESTRING) ||
           (Op->Asl.ParseOpcode == PARSEOP_NAMESEG)    ||
           (Op->Asl.ParseOpcode == PARSEOP_METHODCALL) ||
           (Op->Asl.ParseOpcode == PARSEOP_EXTERNAL)   ||
           (Op->Asl.ParseOpcode == PARSEOP_CONDREFOF))
       {
           /*
            * These are name references, do not push the scope stack
            * for them.
            */
           Flags |= ACPI_NS_DONT_OPEN_SCOPE;
       }
   
       /* Get the NamePath from the appropriate place */
   
       if (OpInfo->Flags & AML_NAMED)
       {
           /* For nearly all NAMED operators, the name reference is the first child */
   
           Path = Op->Asl.Child->Asl.Value.String;
           if (Op->Asl.AmlOpcode == AML_ALIAS_OP)
           {
               /*
                * ALIAS is the only oddball opcode, the name declaration
                * (alias name) is the second operand
                */
               Path = Op->Asl.Child->Asl.Next->Asl.Value.String;
           }
       }
       else if (OpInfo->Flags & AML_CREATE)
       {
           /* Name must appear as the last parameter */
   
           NextOp = Op->Asl.Child;
           while (!(NextOp->Asl.CompileFlags & OP_IS_NAME_DECLARATION))
           {
               NextOp = NextOp->Asl.Next;
           }
   
           Path = NextOp->Asl.Value.String;
       }
       else
       {
           Path = Op->Asl.Value.String;
       }
   
       ObjectType = AslMapNamedOpcodeToDataType (Op->Asl.AmlOpcode);
       ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
           "Type=%s\n", AcpiUtGetTypeName (ObjectType)));
   
       /*
        * Lookup the name in the namespace. Name must exist at this point, or it
        * is an invalid reference.
        *
        * The namespace is also used as a lookup table for references to resource
        * descriptors and the fields within them.
        */
       AslGbl_NsLookupCount++;
   
       Status = AcpiNsLookup (WalkState->ScopeInfo, Path, ObjectType,
           ACPI_IMODE_EXECUTE, Flags, WalkState, &Node);
       if (ACPI_FAILURE (Status))
       {
           if (Status == AE_NOT_FOUND)
           {
               /*
                * We didn't find the name reference by path -- we can qualify this
                * a little better before we print an error message
                */
   
               if ((Op->Asl.Parent) &&
                   (Op->Asl.Parent->Asl.ParseOpcode == PARSEOP_CONDREFOF))
               {
                   /*
                    * One special case: CondRefOf operator - if the name doesn't
                    * exist at this point, it means that there's no actual or
                    * external declaration. If the name is not found, just ignore
                    * it, the point of the operator is to determine if the name
                    * exists at runtime. We wanted to see if this named object
                    * exists to facilitate analysis to allow protected usage of
                    * undeclared externals.
                    */
                   return_ACPI_STATUS (AE_OK);
               }
               else if (strlen (Path) == ACPI_NAMESEG_SIZE)
               {
                   /* A simple, one-segment ACPI name */
   
                   if (XfObjectExists (Path))
                   {
                       /*
                        * There exists such a name, but we couldn't get to it
                        * from this scope
                        */
                       AslError (ASL_ERROR, ASL_MSG_NOT_REACHABLE, Op,
                           Op->Asl.ExternalName);
                   }
                   else
                   {
                       /* The name doesn't exist, period */
   
                       AslError (ASL_ERROR, ASL_MSG_NOT_EXIST,
                           Op, Op->Asl.ExternalName);
                   }
               }
               else
               {
                   /* The NamePath contains multiple NameSegs */
   
                   if ((OpInfo->Flags & AML_CREATE) ||
                       (OpInfo->ObjectType == ACPI_TYPE_LOCAL_ALIAS))
                   {
                       /*
                        * The new name is the last parameter. For the
                        * CreateXXXXField and Alias operators
                        */
                       NextOp = Op->Asl.Child;
                       while (!(NextOp->Asl.CompileFlags & OP_IS_NAME_DECLARATION))
                       {
                           NextOp = NextOp->Asl.Next;
                       }
   
                       AslError (ASL_ERROR, ASL_MSG_PREFIX_NOT_EXIST, NextOp,
                           NextOp->Asl.ExternalName);
                   }
                   else if (OpInfo->Flags & AML_NAMED)
                   {
                       /* The new name is the first parameter */
   
                       AslError (ASL_ERROR, ASL_MSG_PREFIX_NOT_EXIST, Op,
                           Op->Asl.ExternalName);
                   }
                   else if (Path[0] == AML_ROOT_PREFIX)
                   {
                       /* Full namepath from root, the object does not exist */
   
                       AslError (ASL_ERROR, ASL_MSG_NOT_EXIST, Op,
                           Op->Asl.ExternalName);
                   }
                   else
                   {
                       /*
                        * Generic "not found" error. Cannot determine whether it
                        * doesn't exist or just can't be reached. However, we
                        * can differentiate between a NameSeg vs. NamePath.
                        */
                       if (strlen (Op->Asl.ExternalName) == ACPI_NAMESEG_SIZE)
                       {
                           AslError (ASL_ERROR, ASL_MSG_NOT_FOUND, Op,
                               Op->Asl.ExternalName);
                       }
                       else
                       {
                           AslError (ASL_ERROR, ASL_MSG_NAMEPATH_NOT_EXIST, Op,
                               Op->Asl.ExternalName);
                       }
                   }
               }
   
               Status = AE_OK;
           }
   
           return_ACPI_STATUS (Status);
       }
   
       /* Check for an attempt to access an object in another method */
   
       if (!XfValidateCrossReference (Op, OpInfo, Node))
       {
           AslError (ASL_ERROR, ASL_MSG_TEMPORARY_OBJECT, Op,
               Op->Asl.ExternalName);
           return_ACPI_STATUS (Status);
       }
   
      /* Object was found above, check for an illegal forward reference */
   
       if (Op->Asl.CompileFlags & OP_NOT_FOUND_DURING_LOAD)
       {
           /*
            * During the load phase, this Op was flagged as a possible
            * illegal forward reference. In other words, Op is a name path or
            * name segment that refers to a named object declared after the
            * reference. In this scinario, Node refers to the actual declaration
            * and Op is a parse node that references the named object.
            *
            * Note:
            *
            * Object references inside of control methods are allowed to
            * refer to objects declared outside of control methods.
            *
            * If the declaration and reference are both contained inside of the
            * same method or outside of any method, this is a forward reference
            * and should be reported as a compiler error.
            */
           DeclarationParentMethod = UtGetParentMethodNode (Node);
           ReferenceParentMethod = UtGetParentMethodOp (Op);
   
           /* case 1: declaration and reference are both outside of method */
   
           if (!ReferenceParentMethod && !DeclarationParentMethod)
           {
               AslError (ASL_ERROR, ASL_MSG_ILLEGAL_FORWARD_REF, Op,
                   Op->Asl.ExternalName);
           }
   
           /* case 2: declaration and reference are both inside of the same method */
   
           else if (ReferenceParentMethod && DeclarationParentMethod &&
               ReferenceParentMethod == DeclarationParentMethod->Op)
           {
                AslError (ASL_ERROR, ASL_MSG_ILLEGAL_FORWARD_REF, Op,
                   Op->Asl.ExternalName);
           }
       }
   
       /* Check for a reference vs. name declaration */
   
       if (!(OpInfo->Flags & AML_NAMED) &&
           !(OpInfo->Flags & AML_CREATE))
       {
           /* This node has been referenced, mark it for reference check */
   
           Node->Flags |= ANOBJ_IS_REFERENCED;
       }
   
       /*
        * Attempt to optimize the NamePath
        *
        * One special case: CondRefOf operator - not all AML interpreter
        * implementations expect optimized namepaths as a parameter to this
        * operator. They require relative name paths with prefix operators or
        * namepaths starting with the root scope.
        *
        * Other AML interpreter implementations do not perform the namespace
        * search that starts at the current scope and recursively searching the
        * parent scope until the root scope. The lack of search is only known to
        * occur for the namestring parameter for the CondRefOf operator.
        */
       if ((Op->Asl.Parent) &&
           (Op->Asl.Parent->Asl.ParseOpcode != PARSEOP_CONDREFOF))
       {
           OptOptimizeNamePath (Op, OpInfo->Flags, WalkState, Path, Node);
       }
   
       /*
        * 1) Dereference an alias (A name reference that is an alias)
        *    Aliases are not nested, the alias always points to the final object
        */
       if ((Op->Asl.ParseOpcode != PARSEOP_ALIAS) &&
           (Node->Type == ACPI_TYPE_LOCAL_ALIAS))
       {
           /* This node points back to the original PARSEOP_ALIAS */
   
           NextOp = Node->Op;
   
           /* The first child is the alias target op */
   
           NextOp = NextOp->Asl.Child;
   
           /* That in turn points back to original target alias node */
   
           if (NextOp->Asl.Node)
           {
               Node = NextOp->Asl.Node;
           }
   
           /* Else - forward reference to alias, will be resolved later */
       }
   
       /* 2) Check for a reference to a resource descriptor */
   
       if ((Node->Type == ACPI_TYPE_LOCAL_RESOURCE_FIELD) ||
           (Node->Type == ACPI_TYPE_LOCAL_RESOURCE))
       {
           /*
            * This was a reference to a field within a resource descriptor.
            * Extract the associated field offset (either a bit or byte
            * offset depending on the field type) and change the named
            * reference into an integer for AML code generation
            */
           Offset = Node->Value;
           TagBitLength = Node->Length;
   
           /*
            * If a field is being created, generate the length (in bits) of
            * the field. Note: Opcodes other than CreateXxxField and Index
            * can come through here. For other opcodes, we just need to
            * convert the resource tag reference to an integer offset.
            */
           switch (Op->Asl.Parent->Asl.AmlOpcode)
           {
           case AML_CREATE_FIELD_OP: /* Variable "Length" field, in bits */
               /*
                * We know the length operand is an integer constant because
                * we know that it contains a reference to a resource
                * descriptor tag.
                */
               FieldBitLength = (UINT32) Op->Asl.Next->Asl.Value.Integer;
               break;
   
           case AML_CREATE_BIT_FIELD_OP:
   
               FieldBitLength = 1;
               break;
   
           case AML_CREATE_BYTE_FIELD_OP:
           case AML_INDEX_OP:
   
               FieldBitLength = 8;
               break;
   
           case AML_CREATE_WORD_FIELD_OP:
   
               FieldBitLength = 16;
               break;
   
           case AML_CREATE_DWORD_FIELD_OP:
   
               FieldBitLength = 32;
               break;
   
           case AML_CREATE_QWORD_FIELD_OP:
   
               FieldBitLength = 64;
               break;
   
           default:
   
               FieldBitLength = 0;
               break;
           }
   
           /* Check the field length against the length of the resource tag */
   
           if (FieldBitLength)
           {
               if (TagBitLength < FieldBitLength)
               {
                   Message = ASL_MSG_TAG_SMALLER;
               }
               else if (TagBitLength > FieldBitLength)
               {
                   Message = ASL_MSG_TAG_LARGER;
               }
   
               if (Message)
               {
                   sprintf (AslGbl_MsgBuffer,
                       "Size mismatch, Tag: %u bit%s, Field: %u bit%s",
                       TagBitLength, (TagBitLength > 1) ? "s" : "",
                       FieldBitLength, (FieldBitLength > 1) ? "s" : "");
   
                   AslError (ASL_WARNING, Message, Op, AslGbl_MsgBuffer);
               }
           }
   
           /* Convert the BitOffset to a ByteOffset for certain opcodes */
   
           switch (Op->Asl.Parent->Asl.AmlOpcode)
           {
           case AML_CREATE_BYTE_FIELD_OP:
           case AML_CREATE_WORD_FIELD_OP:
           case AML_CREATE_DWORD_FIELD_OP:
           case AML_CREATE_QWORD_FIELD_OP:
           case AML_INDEX_OP:
   
               Offset = ACPI_DIV_8 (Offset);
               break;
   
           default:
   
               break;
           }
   
           /* Now convert this node to an integer whose value is the field offset */
   
           Op->Asl.AmlLength = 0;
           Op->Asl.ParseOpcode = PARSEOP_INTEGER;
           Op->Asl.Value.Integer = (UINT64) Offset;
           Op->Asl.CompileFlags |= OP_IS_RESOURCE_FIELD;
   
           OpcGenerateAmlOpcode (Op);
       }
   
       /* 3) Check for a method invocation */
   
       else if ((((Op->Asl.ParseOpcode == PARSEOP_NAMESTRING) || (Op->Asl.ParseOpcode == PARSEOP_NAMESEG)) &&
                   (Node->Type == ACPI_TYPE_METHOD) &&
                   (Op->Asl.Parent) &&
                   (Op->Asl.Parent->Asl.ParseOpcode != PARSEOP_METHOD))   ||
   
                   (Op->Asl.ParseOpcode == PARSEOP_METHODCALL))
       {
           /*
            * A reference to a method within one of these opcodes is not an
            * invocation of the method, it is simply a reference to the method.
            *
            * September 2016: Removed DeRefOf from this list
            * July 2020: Added Alias to this list
            */
          if ((Op->Asl.Parent) &&
              ((Op->Asl.Parent->Asl.ParseOpcode == PARSEOP_REFOF)     ||
              (Op->Asl.Parent->Asl.ParseOpcode == PARSEOP_PACKAGE)    ||
              (Op->Asl.Parent->Asl.ParseOpcode == PARSEOP_VAR_PACKAGE)||
              (Op->Asl.Parent->Asl.ParseOpcode == PARSEOP_OBJECTTYPE) ||
              (Op->Asl.Parent->Asl.ParseOpcode == PARSEOP_ALIAS)))
          {
              return_ACPI_STATUS (AE_OK);
          }
  
          /*
           * There are two types of method invocation:
           * 1) Invocation with arguments -- the parser recognizes this
           *    as a METHODCALL.
           * 2) Invocation with no arguments --the parser cannot determine that
           *    this is a method invocation, therefore we have to figure it out
           *    here.
           */
          if (Node->Type != ACPI_TYPE_METHOD)
          {
              sprintf (AslGbl_MsgBuffer, "%s is a %s",
                  Op->Asl.ExternalName, AcpiUtGetTypeName (Node->Type));
  
              AslError (ASL_ERROR, ASL_MSG_NOT_METHOD, Op, AslGbl_MsgBuffer);
              return_ACPI_STATUS (AE_OK);
          }
  
          /* Save the method node in the caller's op */
  
          Op->Asl.Node = Node;
          if (Op->Asl.Parent->Asl.ParseOpcode == PARSEOP_CONDREFOF)
          {
              return_ACPI_STATUS (AE_OK);
          }
  
          /*
           * This is a method invocation, with or without arguments.
           * Count the number of arguments, each appears as a child
           * under the parent node
           */
          Op->Asl.ParseOpcode = PARSEOP_METHODCALL;
          UtSetParseOpName (Op);
  
          PassedArgs = 0;
          NextOp = Op->Asl.Child;
  
          while (NextOp)
          {
              PassedArgs++;
              NextOp = NextOp->Asl.Next;
          }
  
          if (Node->Value != ASL_EXTERNAL_METHOD_UNKNOWN_PARAMS &&
              Op->Asl.Parent->Asl.ParseOpcode != PARSEOP_EXTERNAL)
          {
              /*
               * Check the parsed arguments with the number expected by the
               * method declaration itself
               */
              if (PassedArgs != Node->Value)
              {
                  if (Node->Flags & ANOBJ_IS_EXTERNAL)
                  {
                      sprintf (AslGbl_MsgBuffer,
                          "according to previous use, %s requires %u",
                          Op->Asl.ExternalName, Node->Value);
                  }
                  else
                  {
                      sprintf (AslGbl_MsgBuffer, "%s requires %u", Op->Asl.ExternalName,
                          Node->Value);
                  }
  
                  if (PassedArgs < Node->Value)
                  {
                      AslError (ASL_ERROR, ASL_MSG_ARG_COUNT_LO, Op, AslGbl_MsgBuffer);
                  }
                  else
                  {
                      AslError (ASL_ERROR, ASL_MSG_ARG_COUNT_HI, Op, AslGbl_MsgBuffer);
                  }
              }
          }
  
          /*
           * At this point, a method call to an external method has been
           * detected. As of 11/19/2019, iASL does not support parameter counts
           * for methods declared as external. Therefore, save the parameter
           * count of the first method call and use this count check other
           * method calls to ensure that the methods are being called with the
           * same amount of parameters.
           */
          else if (Node->Type == ACPI_TYPE_METHOD &&
              (Node->Flags & ANOBJ_IS_EXTERNAL) &&
              Node->Value == ASL_EXTERNAL_METHOD_UNKNOWN_PARAMS &&
              Op->Asl.Parent->Asl.ParseOpcode != PARSEOP_EXTERNAL)
          {
              Node->Value = PassedArgs;
          }
      }
  
      /* 4) Check for an ASL Field definition */
  
      else if ((Op->Asl.Parent) &&
              ((Op->Asl.Parent->Asl.ParseOpcode == PARSEOP_FIELD)     ||
               (Op->Asl.Parent->Asl.ParseOpcode == PARSEOP_BANKFIELD)))
      {
          /*
           * Offset checking for fields. If the parent operation region has a
           * constant length (known at compile time), we can check fields
           * defined in that region against the region length. This will catch
           * fields and field units that cannot possibly fit within the region.
           *
           * Note: Index fields do not directly reference an operation region,
           * thus they are not included in this check.
           */
          if (Op == Op->Asl.Parent->Asl.Child)
          {
              /*
               * This is the first child of the field node, which is
               * the name of the region. Get the parse node for the
               * region -- which contains the length of the region.
               */
              OwningOp = Node->Op;
              Op->Asl.Parent->Asl.ExtraValue =
                  ACPI_MUL_8 ((UINT32) OwningOp->Asl.Value.Integer);
  
              /* Examine the field access width */
  
              switch ((UINT8) Op->Asl.Parent->Asl.Value.Integer)
              {
              case AML_FIELD_ACCESS_ANY:
              case AML_FIELD_ACCESS_BYTE:
              case AML_FIELD_ACCESS_BUFFER:
              default:
  
                  MinimumLength = 1;
                  break;
  
              case AML_FIELD_ACCESS_WORD:
  
                  MinimumLength = 2;
                  break;
  
              case AML_FIELD_ACCESS_DWORD:
  
                  MinimumLength = 4;
                  break;
  
              case AML_FIELD_ACCESS_QWORD:
  
                  MinimumLength = 8;
                  break;
              }
  
              /*
               * Is the region at least as big as the access width?
               * Note: DataTableRegions have 0 length
               */
              if (((UINT32) OwningOp->Asl.Value.Integer) &&
                  ((UINT32) OwningOp->Asl.Value.Integer < MinimumLength))
              {
                  AslError (ASL_ERROR, ASL_MSG_FIELD_ACCESS_WIDTH, Op, NULL);
              }
  
              /*
               * Check EC/CMOS/SMBUS fields to make sure that the correct
               * access type is used (BYTE for EC/CMOS, BUFFER for SMBUS)
               */
              SpaceIdOp = OwningOp->Asl.Child->Asl.Next;
              switch ((UINT32) SpaceIdOp->Asl.Value.Integer)
              {
              case ACPI_ADR_SPACE_EC:
              case ACPI_ADR_SPACE_CMOS:
              case ACPI_ADR_SPACE_GPIO:
  
                  if ((UINT8) Op->Asl.Parent->Asl.Value.Integer !=
                      AML_FIELD_ACCESS_BYTE)
                  {
                      AslError (ASL_ERROR, ASL_MSG_REGION_BYTE_ACCESS, Op, NULL);
                  }
                  break;
  
              case ACPI_ADR_SPACE_SMBUS:
              case ACPI_ADR_SPACE_IPMI:
              case ACPI_ADR_SPACE_GSBUS:
  
                  if ((UINT8) Op->Asl.Parent->Asl.Value.Integer !=
                      AML_FIELD_ACCESS_BUFFER)
                  {
                      AslError (ASL_ERROR, ASL_MSG_REGION_BUFFER_ACCESS, Op, NULL);
                  }
                  break;
  
              default:
  
                  /* Nothing to do for other address spaces */
  
                  break;
              }
          }
          else
          {
              /*
               * This is one element of the field list. Check to make sure
               * that it does not go beyond the end of the parent operation region.
               *
               * In the code below:
               *    Op->Asl.Parent->Asl.ExtraValue      - Region Length (bits)
               *    Op->Asl.ExtraValue                  - Field start offset (bits)
               *    Op->Asl.Child->Asl.Value.Integer32  - Field length (bits)
               *    Op->Asl.Child->Asl.ExtraValue       - Field access width (bits)
               */
              if (Op->Asl.Parent->Asl.ExtraValue && Op->Asl.Child)
              {
                  XfCheckFieldRange (Op,
                      Op->Asl.Parent->Asl.ExtraValue,
                      Op->Asl.ExtraValue,
                      (UINT32) Op->Asl.Child->Asl.Value.Integer,
                      Op->Asl.Child->Asl.ExtraValue);
              }
          }
      }
  
      /*
       * 5) Check for external resolution
       *
       * By this point, everything should be loaded in the namespace. If a
       * namespace lookup results in a namespace node that is an external, it
       * means that this named object was not defined in the input ASL. This
       * causes issues because there are plenty of incidents where developers
       * use the external keyword to suppress compiler errors about undefined
       * objects. Note: this only applies when compiling multiple definition
       * blocks.
       *
       * Do not check for external resolution in the following cases:
       *
       * case 1) External (ABCD)
       *
       *         This declares ABCD as an external so there is no requirement for
       *         ABCD to be loaded in the namespace when analyzing the actual
       *         External() statement.
       *
       * case 2) CondRefOf (ABCD)
       *
       *         This operator will query the ACPI namespace on the existence of
       *         ABCD. If ABCD does not exist, this operator will return a 0
       *         without incurring AML runtime errors. Therefore, ABCD is allowed
       *         to not exist when analyzing the CondRefOf operator.
       *
       * case 3) External (ABCD)
       *         if (CondRefOf (ABCD))
       *         {
       *             Store (0, ABCD)
       *         }
       *
       *         In this case, ABCD is accessed only if it exists due to the if
       *         statement so there is no need to flag the ABCD nested in the
       *         store operator.
       */
      if (AslGbl_ParseTreeRoot->Asl.Child && AslGbl_ParseTreeRoot->Asl.Child->Asl.Next &&
          (Node->Flags & ANOBJ_IS_EXTERNAL) &&
          Op->Asl.Parent->Asl.ParseOpcode != PARSEOP_EXTERNAL &&
          Op->Asl.ParseOpcode != PARSEOP_EXTERNAL &&
          Op->Asl.Parent->Asl.ParseOpcode != PARSEOP_CONDREFOF &&
          !XfRefIsGuardedByIfCondRefOf (Node, Op))
      {
          ExternalPath = AcpiNsGetNormalizedPathname (Node, TRUE);
          sprintf (AslGbl_MsgBuffer, "full path of external object: %s",
              ExternalPath);
          AslDualParseOpError (ASL_ERROR, ASL_MSG_UNDEFINED_EXTERNAL, Op, NULL,
              ASL_MSG_EXTERNAL_FOUND_HERE, Node->Op, AslGbl_MsgBuffer);
          if (ExternalPath)
          {
              ACPI_FREE (ExternalPath);
          }
      }
  
      /* 5) Check for a connection object */
  #if 0
      else if (Op->Asl.Parent->Asl.ParseOpcode == PARSEOP_CONNECTION)
      {
          return_ACPI_STATUS (Status);
      }
  #endif
  
      Op->Asl.Node = Node;
      return_ACPI_STATUS (Status);
  }
  
  
  /*******************************************************************************
   *
   * FUNCTION:    XfRefIsGuardedByIfCondRefOf
   *
   * PARAMETERS:  Node        - Named object reference node
   *              Op          - Named object reference parse node
   *
   * RETURN:      BOOLEAN
   *
   * DESCRIPTION: returns true if Op checked inside if (CondRefOf (...))
   *              refers to Node.
   *
   ******************************************************************************/
  
  static BOOLEAN
  XfRefIsGuardedByIfCondRefOf (
      ACPI_NAMESPACE_NODE     *Node,
      ACPI_PARSE_OBJECT       *Op)
  {
      ACPI_PARSE_OBJECT       *Parent = Op->Asl.Parent;
  
  
      while (Parent)
      {
          if (Parent->Asl.ParseOpcode == PARSEOP_IF &&
              XfFindCondRefOfName (Node, Parent->Asl.Child))
          {
              return (TRUE);
          }
  
          Parent = Parent->Asl.Parent;
      }
  
      return (FALSE);
  }
  
  
  /*******************************************************************************
   *
   * FUNCTION:    XfRefIsGuardedByIfCondRefOf
   *
   * PARAMETERS:  Node        - Named object reference node
   *              Op          - Named object reference parse node
   *
   * RETURN:      BOOLEAN
   *
   * DESCRIPTION: returns true if Op checked inside if (CondRefOf (...))
   *              refers to Node.
   *
   ******************************************************************************/
  
  static BOOLEAN
  XfFindCondRefOfName (
      ACPI_NAMESPACE_NODE     *Node,
      ACPI_PARSE_OBJECT       *Op)
  {
      BOOLEAN                 CondRefOfFound = FALSE;
  
  
      if (!Op)
      {
          return (FALSE);
      }
  
      switch (Op->Asl.ParseOpcode)
      {
      case PARSEOP_CONDREFOF:
  
          return (Op->Asl.Child->Common.Node == Node);
          break;
  
      case PARSEOP_LAND:
  
          CondRefOfFound = XfFindCondRefOfName (Node, Op->Asl.Child);
          if (CondRefOfFound)
          {
              return (TRUE);
          }
  
          return (XfFindCondRefOfName (Node, Op->Asl.Child->Asl.Next));
          break;
  
      default:
  
          return (FALSE);
          break;
      }
  }
  
  
  /*******************************************************************************
   *
   * FUNCTION:    XfNamespaceLocateEnd
   *
   * PARAMETERS:  ASL_WALK_CALLBACK
   *
   * RETURN:      Status
   *
   * DESCRIPTION: Ascending callback used during cross reference. We only
   *              need to worry about scope management here.
   *
   ******************************************************************************/
  
  static ACPI_STATUS
  XfNamespaceLocateEnd (
      ACPI_PARSE_OBJECT       *Op,
      UINT32                  Level,
      void                    *Context)
  {
      ACPI_WALK_STATE         *WalkState = (ACPI_WALK_STATE *) Context;
      const ACPI_OPCODE_INFO  *OpInfo;
  
  
      ACPI_FUNCTION_TRACE (XfNamespaceLocateEnd);
  
  
      /* We are only interested in opcodes that have an associated name */
  
      OpInfo = AcpiPsGetOpcodeInfo (Op->Asl.AmlOpcode);
      if (!(OpInfo->Flags & AML_NAMED))
      {
          return_ACPI_STATUS (AE_OK);
      }
  
      /* Not interested in name references, we did not open a scope for them */
  
      if ((Op->Asl.ParseOpcode == PARSEOP_NAMESTRING) ||
          (Op->Asl.ParseOpcode == PARSEOP_NAMESEG)    ||
          (Op->Asl.ParseOpcode == PARSEOP_METHODCALL) ||
          (Op->Asl.ParseOpcode == PARSEOP_EXTERNAL))
      {
          return_ACPI_STATUS (AE_OK);
      }
  
      /* Pop the scope stack if necessary */
  
      if (AcpiNsOpensScope (AslMapNamedOpcodeToDataType (Op->Asl.AmlOpcode)))
      {
  
          ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
              "%s: Popping scope for Op %p\n",
              AcpiUtGetTypeName (OpInfo->ObjectType), Op));
  
          (void) AcpiDsScopeStackPop (WalkState);
      }
  
      return_ACPI_STATUS (AE_OK);
  }
  
  
  /*******************************************************************************
   *
   * FUNCTION:    XfValidateCrossReference
   *
   * PARAMETERS:  Op                      - Parse Op that references the object
   *              OpInfo                  - Parse Op info struct
   *              Node                    - Node for the referenced object
   *
   * RETURN:      TRUE if the reference is legal, FALSE otherwise
   *
   * DESCRIPTION: Determine if a reference to another object is allowed.
   *
   * EXAMPLE:
   *      Method (A) {Name (INT1, 1)}     Declaration of object INT1
   *      Method (B) (Store (2, \A.INT1)} Illegal reference to object INT1
   *                                      (INT1 is temporary, valid only during
   *                                      execution of A)
   *
   * NOTES:
   *      A null pointer returned by either UtGetParentMethodOp or
   *      UtGetParentMethodNode indicates that the parameter object is not
   *      within a control method.
   *
   *      Five cases are handled: Case(Op, Node)
   *      1) Case(0,0): Op is not within a method, Node is not    --> OK
   *      2) Case(0,1): Op is not within a method, but Node is    --> Illegal
   *      3) Case(1,0): Op is within a method, Node is not        --> OK
   *      4) Case(1,1): Both are within the same method           --> OK
   *      5) Case(1,1): Both are in methods, but not same method  --> Illegal
   *
   ******************************************************************************/
  
  static BOOLEAN
  XfValidateCrossReference (
      ACPI_PARSE_OBJECT       *Op,
      const ACPI_OPCODE_INFO  *OpInfo,
      ACPI_NAMESPACE_NODE     *Node)
  {
      ACPI_PARSE_OBJECT       *ReferencingMethodOp;
      ACPI_NAMESPACE_NODE     *ReferencedMethodNode;
  
  
      /* Ignore actual named (and related) object declarations */
  
      if (OpInfo->Flags & (AML_NAMED | AML_CREATE | AML_DEFER | AML_HAS_ARGS))
      {
          return (TRUE);
      }
  
      /*
       * 1) Search upwards in parse tree for owner of the referencing object
       * 2) Search upwards in namespace to find the owner of the referenced object
       */
      ReferencingMethodOp = UtGetParentMethodOp (Op);
      ReferencedMethodNode = UtGetParentMethodNode (Node);
  
      if (!ReferencingMethodOp && !ReferencedMethodNode)
      {
          /*
           * 1) Case (0,0): Both Op and Node are not within methods
           * --> OK
           */
          return (TRUE);
      }
  
      if (!ReferencingMethodOp && ReferencedMethodNode)
      {
          /*
           * 2) Case (0,1): Op is not in a method, but Node is within a
           * method --> illegal
           */
          return (FALSE);
      }
      else if (ReferencingMethodOp && !ReferencedMethodNode)
      {
          /*
           * 3) Case (1,0): Op is within a method, but Node is not
           * --> OK
           */
          return (TRUE);
      }
      else if (ReferencingMethodOp->Asl.Node == ReferencedMethodNode)
      {
          /*
           * 4) Case (1,1): Both Op and Node are within the same method
           * --> OK
           */
          return (TRUE);
      }
      else
      {
          /*
           * 5) Case (1,1), Op and Node are in different methods
           * --> Illegal
           */
          return (FALSE);
      }
  }

Cache object: 08cdd01b9adb683164fe571650b80bef