FreeBSD/Linux Kernel Cross Reference
sys/contrib/openzfs/module/lua/lcode.c

     /*
     ** $Id: lcode.c,v 2.62.1.1 2013/04/12 18:48:47 roberto Exp $
     ** Code generator for Lua
     ** See Copyright Notice in lua.h
     */
     
     #define lcode_c
     #define LUA_CORE
     
    #if defined(HAVE_IMPLICIT_FALLTHROUGH)
    #pragma GCC diagnostic ignored "-Wimplicit-fallthrough"
    #endif
    
    #include <sys/lua/lua.h>
    
    #include "lcode.h"
    #include "ldebug.h"
    #include "ldo.h"
    #include "lgc.h"
    #include "llex.h"
    #include "lmem.h"
    #include "lobject.h"
    #include "lopcodes.h"
    #include "lparser.h"
    #include "lstring.h"
    #include "ltable.h"
    #include "lvm.h"
    
    
    #define hasjumps(e)     ((e)->t != (e)->f)
    
    
    static int isnumeral(expdesc *e) {
      return (e->k == VKNUM && e->t == NO_JUMP && e->f == NO_JUMP);
    }
    
    
    void luaK_nil (FuncState *fs, int from, int n) {
      Instruction *previous;
      int l = from + n - 1;  /* last register to set nil */
      if (fs->pc > fs->lasttarget) {  /* no jumps to current position? */
        previous = &fs->f->code[fs->pc-1];
        if (GET_OPCODE(*previous) == OP_LOADNIL) {
          int pfrom = GETARG_A(*previous);
          int pl = pfrom + GETARG_B(*previous);
          if ((pfrom <= from && from <= pl + 1) ||
              (from <= pfrom && pfrom <= l + 1)) {  /* can connect both? */
            if (pfrom < from) from = pfrom;  /* from = min(from, pfrom) */
            if (pl > l) l = pl;  /* l = max(l, pl) */
            SETARG_A(*previous, from);
            SETARG_B(*previous, l - from);
            return;
          }
        }  /* else go through */
      }
      luaK_codeABC(fs, OP_LOADNIL, from, n - 1, 0);  /* else no optimization */
    }
    
    
    int luaK_jump (FuncState *fs) {
      int jpc = fs->jpc;  /* save list of jumps to here */
      int j;
      fs->jpc = NO_JUMP;
      j = luaK_codeAsBx(fs, OP_JMP, 0, NO_JUMP);
      luaK_concat(fs, &j, jpc);  /* keep them on hold */
      return j;
    }
    
    
    void luaK_ret (FuncState *fs, int first, int nret) {
      luaK_codeABC(fs, OP_RETURN, first, nret+1, 0);
    }
    
    
    static int condjump (FuncState *fs, OpCode op, int A, int B, int C) {
      luaK_codeABC(fs, op, A, B, C);
      return luaK_jump(fs);
    }
    
    
    static void fixjump (FuncState *fs, int pc, int dest) {
      Instruction *jmp = &fs->f->code[pc];
      int offset = dest-(pc+1);
      lua_assert(dest != NO_JUMP);
      if (abs(offset) > MAXARG_sBx)
        luaX_syntaxerror(fs->ls, "control structure too long");
      SETARG_sBx(*jmp, offset);
    }
    
    
    /*
    ** returns current `pc' and marks it as a jump target (to avoid wrong
    ** optimizations with consecutive instructions not in the same basic block).
    */
    int luaK_getlabel (FuncState *fs) {
      fs->lasttarget = fs->pc;
      return fs->pc;
    }
    
   
   static int getjump (FuncState *fs, int pc) {
     int offset = GETARG_sBx(fs->f->code[pc]);
     if (offset == NO_JUMP)  /* point to itself represents end of list */
       return NO_JUMP;  /* end of list */
     else
       return (pc+1)+offset;  /* turn offset into absolute position */
   }
   
   
   static Instruction *getjumpcontrol (FuncState *fs, int pc) {
     Instruction *pi = &fs->f->code[pc];
     if (pc >= 1 && testTMode(GET_OPCODE(*(pi-1))))
       return pi-1;
     else
       return pi;
   }
   
   
   /*
   ** check whether list has any jump that do not produce a value
   ** (or produce an inverted value)
   */
   static int need_value (FuncState *fs, int list) {
     for (; list != NO_JUMP; list = getjump(fs, list)) {
       Instruction i = *getjumpcontrol(fs, list);
       if (GET_OPCODE(i) != OP_TESTSET) return 1;
     }
     return 0;  /* not found */
   }
   
   
   static int patchtestreg (FuncState *fs, int node, int reg) {
     Instruction *i = getjumpcontrol(fs, node);
     if (GET_OPCODE(*i) != OP_TESTSET)
       return 0;  /* cannot patch other instructions */
     if (reg != NO_REG && reg != GETARG_B(*i))
       SETARG_A(*i, reg);
     else  /* no register to put value or register already has the value */
       *i = CREATE_ABC(OP_TEST, GETARG_B(*i), 0, GETARG_C(*i));
   
     return 1;
   }
   
   
   static void removevalues (FuncState *fs, int list) {
     for (; list != NO_JUMP; list = getjump(fs, list))
         patchtestreg(fs, list, NO_REG);
   }
   
   
   static void patchlistaux (FuncState *fs, int list, int vtarget, int reg,
                             int dtarget) {
     while (list != NO_JUMP) {
       int next = getjump(fs, list);
       if (patchtestreg(fs, list, reg))
         fixjump(fs, list, vtarget);
       else
         fixjump(fs, list, dtarget);  /* jump to default target */
       list = next;
     }
   }
   
   
   static void dischargejpc (FuncState *fs) {
     patchlistaux(fs, fs->jpc, fs->pc, NO_REG, fs->pc);
     fs->jpc = NO_JUMP;
   }
   
   
   void luaK_patchlist (FuncState *fs, int list, int target) {
     if (target == fs->pc)
       luaK_patchtohere(fs, list);
     else {
       lua_assert(target < fs->pc);
       patchlistaux(fs, list, target, NO_REG, target);
     }
   }
   
   
   LUAI_FUNC void luaK_patchclose (FuncState *fs, int list, int level) {
     level++;  /* argument is +1 to reserve 0 as non-op */
     while (list != NO_JUMP) {
       int next = getjump(fs, list);
       lua_assert(GET_OPCODE(fs->f->code[list]) == OP_JMP &&
                   (GETARG_A(fs->f->code[list]) == 0 ||
                    GETARG_A(fs->f->code[list]) >= level));
       SETARG_A(fs->f->code[list], level);
       list = next;
     }
   }
   
   
   void luaK_patchtohere (FuncState *fs, int list) {
     luaK_getlabel(fs);
     luaK_concat(fs, &fs->jpc, list);
   }
   
   
   void luaK_concat (FuncState *fs, int *l1, int l2) {
     if (l2 == NO_JUMP) return;
     else if (*l1 == NO_JUMP)
       *l1 = l2;
     else {
       int list = *l1;
       int next;
       while ((next = getjump(fs, list)) != NO_JUMP)  /* find last element */
         list = next;
       fixjump(fs, list, l2);
     }
   }
   
   
   static int luaK_code (FuncState *fs, Instruction i) {
     Proto *f = fs->f;
     dischargejpc(fs);  /* `pc' will change */
     /* put new instruction in code array */
     luaM_growvector(fs->ls->L, f->code, fs->pc, f->sizecode, Instruction,
                     MAX_INT, "opcodes");
     f->code[fs->pc] = i;
     /* save corresponding line information */
     luaM_growvector(fs->ls->L, f->lineinfo, fs->pc, f->sizelineinfo, int,
                     MAX_INT, "opcodes");
     f->lineinfo[fs->pc] = fs->ls->lastline;
     return fs->pc++;
   }
   
   
   int luaK_codeABC (FuncState *fs, OpCode o, int a, int b, int c) {
     lua_assert(getOpMode(o) == iABC);
     lua_assert(getBMode(o) != OpArgN || b == 0);
     lua_assert(getCMode(o) != OpArgN || c == 0);
     lua_assert(a <= MAXARG_A && b <= MAXARG_B && c <= MAXARG_C);
     return luaK_code(fs, CREATE_ABC(o, a, b, c));
   }
   
   
   int luaK_codeABx (FuncState *fs, OpCode o, int a, unsigned int bc) {
     lua_assert(getOpMode(o) == iABx || getOpMode(o) == iAsBx);
     lua_assert(getCMode(o) == OpArgN);
     lua_assert(a <= MAXARG_A && bc <= MAXARG_Bx);
     return luaK_code(fs, CREATE_ABx(o, a, bc));
   }
   
   
   static int codeextraarg (FuncState *fs, int a) {
     lua_assert(a <= MAXARG_Ax);
     return luaK_code(fs, CREATE_Ax(OP_EXTRAARG, a));
   }
   
   
   int luaK_codek (FuncState *fs, int reg, int k) {
     if (k <= MAXARG_Bx)
       return luaK_codeABx(fs, OP_LOADK, reg, k);
     else {
       int p = luaK_codeABx(fs, OP_LOADKX, reg, 0);
       codeextraarg(fs, k);
       return p;
     }
   }
   
   
   void luaK_checkstack (FuncState *fs, int n) {
     int newstack = fs->freereg + n;
     if (newstack > fs->f->maxstacksize) {
       if (newstack >= MAXSTACK)
         luaX_syntaxerror(fs->ls, "function or expression too complex");
       fs->f->maxstacksize = cast_byte(newstack);
     }
   }
   
   
   void luaK_reserveregs (FuncState *fs, int n) {
     luaK_checkstack(fs, n);
     fs->freereg += n;
   }
   
   
   static void freereg (FuncState *fs, int reg) {
     if (!ISK(reg) && reg >= fs->nactvar) {
       fs->freereg--;
       lua_assert(reg == fs->freereg);
     }
   }
   
   
   static void freeexp (FuncState *fs, expdesc *e) {
     if (e->k == VNONRELOC)
       freereg(fs, e->u.info);
   }
   
   
   static int addk (FuncState *fs, TValue *key, TValue *v) {
     lua_State *L = fs->ls->L;
     TValue *idx = luaH_set(L, fs->h, key);
     Proto *f = fs->f;
     int k, oldsize;
     if (ttisnumber(idx)) {
       lua_Number n = nvalue(idx);
       lua_number2int(k, n);
       if (luaV_rawequalobj(&f->k[k], v))
         return k;
       /* else may be a collision (e.g., between 0.0 and "\0\0\0\0\0\0\0\0");
          go through and create a new entry for this value */
     }
     /* constant not found; create a new entry */
     oldsize = f->sizek;
     k = fs->nk;
     /* numerical value does not need GC barrier;
        table has no metatable, so it does not need to invalidate cache */
     setnvalue(idx, cast_num(k));
     luaM_growvector(L, f->k, k, f->sizek, TValue, MAXARG_Ax, "constants");
     while (oldsize < f->sizek) setnilvalue(&f->k[oldsize++]);
     setobj(L, &f->k[k], v);
     fs->nk++;
     luaC_barrier(L, f, v);
     return k;
   }
   
   
   int luaK_stringK (FuncState *fs, TString *s) {
     TValue o;
     setsvalue(fs->ls->L, &o, s);
     return addk(fs, &o, &o);
   }
   
   
   int luaK_numberK (FuncState *fs, lua_Number r) {
     int n;
     lua_State *L = fs->ls->L;
     TValue o;
     setnvalue(&o, r);
     if (r == 0 || luai_numisnan(NULL, r)) {  /* handle -0 and NaN */
       /* use raw representation as key to avoid numeric problems */
       setsvalue(L, L->top++, luaS_newlstr(L, (char *)&r, sizeof(r)));
       n = addk(fs, L->top - 1, &o);
       L->top--;
     }
     else
       n = addk(fs, &o, &o);  /* regular case */
     return n;
   }
   
   
   static int boolK (FuncState *fs, int b) {
     TValue o;
     setbvalue(&o, b);
     return addk(fs, &o, &o);
   }
   
   
   static int nilK (FuncState *fs) {
     TValue k, v;
     setnilvalue(&v);
     /* cannot use nil as key; instead use table itself to represent nil */
     sethvalue(fs->ls->L, &k, fs->h);
     return addk(fs, &k, &v);
   }
   
   
   void luaK_setreturns (FuncState *fs, expdesc *e, int nresults) {
     if (e->k == VCALL) {  /* expression is an open function call? */
       SETARG_C(getcode(fs, e), nresults+1);
     }
     else if (e->k == VVARARG) {
       SETARG_B(getcode(fs, e), nresults+1);
       SETARG_A(getcode(fs, e), fs->freereg);
       luaK_reserveregs(fs, 1);
     }
   }
   
   
   void luaK_setoneret (FuncState *fs, expdesc *e) {
     if (e->k == VCALL) {  /* expression is an open function call? */
       e->k = VNONRELOC;
       e->u.info = GETARG_A(getcode(fs, e));
     }
     else if (e->k == VVARARG) {
       SETARG_B(getcode(fs, e), 2);
       e->k = VRELOCABLE;  /* can relocate its simple result */
     }
   }
   
   
   void luaK_dischargevars (FuncState *fs, expdesc *e) {
     switch (e->k) {
       case VLOCAL: {
         e->k = VNONRELOC;
         break;
       }
       case VUPVAL: {
         e->u.info = luaK_codeABC(fs, OP_GETUPVAL, 0, e->u.info, 0);
         e->k = VRELOCABLE;
         break;
       }
       case VINDEXED: {
         OpCode op = OP_GETTABUP;  /* assume 't' is in an upvalue */
         freereg(fs, e->u.ind.idx);
         if (e->u.ind.vt == VLOCAL) {  /* 't' is in a register? */
           freereg(fs, e->u.ind.t);
           op = OP_GETTABLE;
         }
         e->u.info = luaK_codeABC(fs, op, 0, e->u.ind.t, e->u.ind.idx);
         e->k = VRELOCABLE;
         break;
       }
       case VVARARG:
       case VCALL: {
         luaK_setoneret(fs, e);
         break;
       }
       default: break;  /* there is one value available (somewhere) */
     }
   }
   
   
   static int code_label (FuncState *fs, int A, int b, int jump) {
     luaK_getlabel(fs);  /* those instructions may be jump targets */
     return luaK_codeABC(fs, OP_LOADBOOL, A, b, jump);
   }
   
   
   static void discharge2reg (FuncState *fs, expdesc *e, int reg) {
     luaK_dischargevars(fs, e);
     switch (e->k) {
       case VNIL: {
         luaK_nil(fs, reg, 1);
         break;
       }
       case VFALSE: case VTRUE: {
         luaK_codeABC(fs, OP_LOADBOOL, reg, e->k == VTRUE, 0);
         break;
       }
       case VK: {
         luaK_codek(fs, reg, e->u.info);
         break;
       }
       case VKNUM: {
         luaK_codek(fs, reg, luaK_numberK(fs, e->u.nval));
         break;
       }
       case VRELOCABLE: {
         Instruction *pc = &getcode(fs, e);
         SETARG_A(*pc, reg);
         break;
       }
       case VNONRELOC: {
         if (reg != e->u.info)
           luaK_codeABC(fs, OP_MOVE, reg, e->u.info, 0);
         break;
       }
       default: {
         lua_assert(e->k == VVOID || e->k == VJMP);
         return;  /* nothing to do... */
       }
     }
     e->u.info = reg;
     e->k = VNONRELOC;
   }
   
   
   static void discharge2anyreg (FuncState *fs, expdesc *e) {
     if (e->k != VNONRELOC) {
       luaK_reserveregs(fs, 1);
       discharge2reg(fs, e, fs->freereg-1);
     }
   }
   
   
   static void exp2reg (FuncState *fs, expdesc *e, int reg) {
     discharge2reg(fs, e, reg);
     if (e->k == VJMP)
       luaK_concat(fs, &e->t, e->u.info);  /* put this jump in `t' list */
     if (hasjumps(e)) {
       int final;  /* position after whole expression */
       int p_f = NO_JUMP;  /* position of an eventual LOAD false */
       int p_t = NO_JUMP;  /* position of an eventual LOAD true */
       if (need_value(fs, e->t) || need_value(fs, e->f)) {
         int fj = (e->k == VJMP) ? NO_JUMP : luaK_jump(fs);
         p_f = code_label(fs, reg, 0, 1);
         p_t = code_label(fs, reg, 1, 0);
         luaK_patchtohere(fs, fj);
       }
       final = luaK_getlabel(fs);
       patchlistaux(fs, e->f, final, reg, p_f);
       patchlistaux(fs, e->t, final, reg, p_t);
     }
     e->f = e->t = NO_JUMP;
     e->u.info = reg;
     e->k = VNONRELOC;
   }
   
   
   void luaK_exp2nextreg (FuncState *fs, expdesc *e) {
     luaK_dischargevars(fs, e);
     freeexp(fs, e);
     luaK_reserveregs(fs, 1);
     exp2reg(fs, e, fs->freereg - 1);
   }
   
   
   int luaK_exp2anyreg (FuncState *fs, expdesc *e) {
     luaK_dischargevars(fs, e);
     if (e->k == VNONRELOC) {
       if (!hasjumps(e)) return e->u.info;  /* exp is already in a register */
       if (e->u.info >= fs->nactvar) {  /* reg. is not a local? */
         exp2reg(fs, e, e->u.info);  /* put value on it */
         return e->u.info;
       }
     }
     luaK_exp2nextreg(fs, e);  /* default */
     return e->u.info;
   }
   
   
   void luaK_exp2anyregup (FuncState *fs, expdesc *e) {
     if (e->k != VUPVAL || hasjumps(e))
       luaK_exp2anyreg(fs, e);
   }
   
   
   void luaK_exp2val (FuncState *fs, expdesc *e) {
     if (hasjumps(e))
       luaK_exp2anyreg(fs, e);
     else
       luaK_dischargevars(fs, e);
   }
   
   
   int luaK_exp2RK (FuncState *fs, expdesc *e) {
     luaK_exp2val(fs, e);
     switch (e->k) {
       case VTRUE:
       case VFALSE:
       case VNIL: {
         if (fs->nk <= MAXINDEXRK) {  /* constant fits in RK operand? */
           e->u.info = (e->k == VNIL) ? nilK(fs) : boolK(fs, (e->k == VTRUE));
           e->k = VK;
           return RKASK(e->u.info);
         }
         else break;
       }
       case VKNUM: {
         e->u.info = luaK_numberK(fs, e->u.nval);
         e->k = VK;
         /* go through */
       }
       case VK: {
         if (e->u.info <= MAXINDEXRK)  /* constant fits in argC? */
           return RKASK(e->u.info);
         else break;
       }
       default: break;
     }
     /* not a constant in the right range: put it in a register */
     return luaK_exp2anyreg(fs, e);
   }
   
   
   void luaK_storevar (FuncState *fs, expdesc *var, expdesc *ex) {
     switch (var->k) {
       case VLOCAL: {
         freeexp(fs, ex);
         exp2reg(fs, ex, var->u.info);
         return;
       }
       case VUPVAL: {
         int e = luaK_exp2anyreg(fs, ex);
         luaK_codeABC(fs, OP_SETUPVAL, e, var->u.info, 0);
         break;
       }
       case VINDEXED: {
         OpCode op = (var->u.ind.vt == VLOCAL) ? OP_SETTABLE : OP_SETTABUP;
         int e = luaK_exp2RK(fs, ex);
         luaK_codeABC(fs, op, var->u.ind.t, var->u.ind.idx, e);
         break;
       }
       default: {
         lua_assert(0);  /* invalid var kind to store */
         break;
       }
     }
     freeexp(fs, ex);
   }
   
   
   void luaK_self (FuncState *fs, expdesc *e, expdesc *key) {
     int ereg;
     luaK_exp2anyreg(fs, e);
     ereg = e->u.info;  /* register where 'e' was placed */
     freeexp(fs, e);
     e->u.info = fs->freereg;  /* base register for op_self */
     e->k = VNONRELOC;
     luaK_reserveregs(fs, 2);  /* function and 'self' produced by op_self */
     luaK_codeABC(fs, OP_SELF, e->u.info, ereg, luaK_exp2RK(fs, key));
     freeexp(fs, key);
   }
   
   
   static void invertjump (FuncState *fs, expdesc *e) {
     Instruction *pc = getjumpcontrol(fs, e->u.info);
     lua_assert(testTMode(GET_OPCODE(*pc)) && GET_OPCODE(*pc) != OP_TESTSET &&
                                              GET_OPCODE(*pc) != OP_TEST);
     SETARG_A(*pc, !(GETARG_A(*pc)));
   }
   
   
   static int jumponcond (FuncState *fs, expdesc *e, int cond) {
     if (e->k == VRELOCABLE) {
       Instruction ie = getcode(fs, e);
       if (GET_OPCODE(ie) == OP_NOT) {
         fs->pc--;  /* remove previous OP_NOT */
         return condjump(fs, OP_TEST, GETARG_B(ie), 0, !cond);
       }
       /* else go through */
     }
     discharge2anyreg(fs, e);
     freeexp(fs, e);
     return condjump(fs, OP_TESTSET, NO_REG, e->u.info, cond);
   }
   
   
   void luaK_goiftrue (FuncState *fs, expdesc *e) {
     int pc;  /* pc of last jump */
     luaK_dischargevars(fs, e);
     switch (e->k) {
       case VJMP: {
         invertjump(fs, e);
         pc = e->u.info;
         break;
       }
       case VK: case VKNUM: case VTRUE: {
         pc = NO_JUMP;  /* always true; do nothing */
         break;
       }
       default: {
         pc = jumponcond(fs, e, 0);
         break;
       }
     }
     luaK_concat(fs, &e->f, pc);  /* insert last jump in `f' list */
     luaK_patchtohere(fs, e->t);
     e->t = NO_JUMP;
   }
   
   
   void luaK_goiffalse (FuncState *fs, expdesc *e) {
     int pc;  /* pc of last jump */
     luaK_dischargevars(fs, e);
     switch (e->k) {
       case VJMP: {
         pc = e->u.info;
         break;
       }
       case VNIL: case VFALSE: {
         pc = NO_JUMP;  /* always false; do nothing */
         break;
       }
       default: {
         pc = jumponcond(fs, e, 1);
         break;
       }
     }
     luaK_concat(fs, &e->t, pc);  /* insert last jump in `t' list */
     luaK_patchtohere(fs, e->f);
     e->f = NO_JUMP;
   }
   
   
   static void codenot (FuncState *fs, expdesc *e) {
     luaK_dischargevars(fs, e);
     switch (e->k) {
       case VNIL: case VFALSE: {
         e->k = VTRUE;
         break;
       }
       case VK: case VKNUM: case VTRUE: {
         e->k = VFALSE;
         break;
       }
       case VJMP: {
         invertjump(fs, e);
         break;
       }
       case VRELOCABLE:
       case VNONRELOC: {
         discharge2anyreg(fs, e);
         freeexp(fs, e);
         e->u.info = luaK_codeABC(fs, OP_NOT, 0, e->u.info, 0);
         e->k = VRELOCABLE;
         break;
       }
       default: {
         lua_assert(0);  /* cannot happen */
         break;
       }
     }
     /* interchange true and false lists */
     { int temp = e->f; e->f = e->t; e->t = temp; }
     removevalues(fs, e->f);
     removevalues(fs, e->t);
   }
   
   
   void luaK_indexed (FuncState *fs, expdesc *t, expdesc *k) {
     lua_assert(!hasjumps(t));
     t->u.ind.t = t->u.info;
     t->u.ind.idx = luaK_exp2RK(fs, k);
     t->u.ind.vt = (t->k == VUPVAL) ? VUPVAL
                                    : check_exp(vkisinreg(t->k), VLOCAL);
     t->k = VINDEXED;
   }
   
   
   static int constfolding (OpCode op, expdesc *e1, expdesc *e2) {
     lua_Number r;
     if (!isnumeral(e1) || !isnumeral(e2)) return 0;
     if ((op == OP_DIV || op == OP_MOD) && e2->u.nval == 0)
       return 0;  /* do not attempt to divide by 0 */
     /*
      * Patched: check for MIN_INT / -1
      */
     if (op == OP_DIV && e1->u.nval == INT64_MIN && e2->u.nval == -1)
       return 0;
     r = luaO_arith(op - OP_ADD + LUA_OPADD, e1->u.nval, e2->u.nval);
     e1->u.nval = r;
     return 1;
   }
   
   
   static void codearith (FuncState *fs, OpCode op,
                          expdesc *e1, expdesc *e2, int line) {
     if (constfolding(op, e1, e2))
       return;
     else {
       int o2 = (op != OP_UNM && op != OP_LEN) ? luaK_exp2RK(fs, e2) : 0;
       int o1 = luaK_exp2RK(fs, e1);
       if (o1 > o2) {
         freeexp(fs, e1);
         freeexp(fs, e2);
       }
       else {
         freeexp(fs, e2);
         freeexp(fs, e1);
       }
       e1->u.info = luaK_codeABC(fs, op, 0, o1, o2);
       e1->k = VRELOCABLE;
       luaK_fixline(fs, line);
     }
   }
   
   
   static void codecomp (FuncState *fs, OpCode op, int cond, expdesc *e1,
                                                             expdesc *e2) {
     int o1 = luaK_exp2RK(fs, e1);
     int o2 = luaK_exp2RK(fs, e2);
     freeexp(fs, e2);
     freeexp(fs, e1);
     if (cond == 0 && op != OP_EQ) {
       int temp;  /* exchange args to replace by `<' or `<=' */
       temp = o1; o1 = o2; o2 = temp;  /* o1 <==> o2 */
       cond = 1;
     }
     e1->u.info = condjump(fs, op, cond, o1, o2);
     e1->k = VJMP;
   }
   
   
   void luaK_prefix (FuncState *fs, UnOpr op, expdesc *e, int line) {
     expdesc e2;
     e2.t = e2.f = NO_JUMP; e2.k = VKNUM; e2.u.nval = 0;
     switch (op) {
       case OPR_MINUS: {
         if (isnumeral(e))  /* minus constant? */
           e->u.nval = luai_numunm(NULL, e->u.nval);  /* fold it */
         else {
           luaK_exp2anyreg(fs, e);
           codearith(fs, OP_UNM, e, &e2, line);
         }
         break;
       }
       case OPR_NOT: codenot(fs, e); break;
       case OPR_LEN: {
         luaK_exp2anyreg(fs, e);  /* cannot operate on constants */
         codearith(fs, OP_LEN, e, &e2, line);
         break;
       }
       default: lua_assert(0);
     }
   }
   
   
   void luaK_infix (FuncState *fs, BinOpr op, expdesc *v) {
     switch (op) {
       case OPR_AND: {
         luaK_goiftrue(fs, v);
         break;
       }
       case OPR_OR: {
         luaK_goiffalse(fs, v);
         break;
       }
       case OPR_CONCAT: {
         luaK_exp2nextreg(fs, v);  /* operand must be on the `stack' */
         break;
       }
       case OPR_ADD: case OPR_SUB: case OPR_MUL: case OPR_DIV:
       case OPR_MOD: case OPR_POW: {
         if (!isnumeral(v)) luaK_exp2RK(fs, v);
         break;
       }
       default: {
         luaK_exp2RK(fs, v);
         break;
       }
     }
   }
   
   
   void luaK_posfix (FuncState *fs, BinOpr op,
                     expdesc *e1, expdesc *e2, int line) {
     switch (op) {
       case OPR_AND: {
         lua_assert(e1->t == NO_JUMP);  /* list must be closed */
         luaK_dischargevars(fs, e2);
         luaK_concat(fs, &e2->f, e1->f);
         *e1 = *e2;
         break;
       }
       case OPR_OR: {
         lua_assert(e1->f == NO_JUMP);  /* list must be closed */
         luaK_dischargevars(fs, e2);
         luaK_concat(fs, &e2->t, e1->t);
         *e1 = *e2;
         break;
       }
       case OPR_CONCAT: {
         luaK_exp2val(fs, e2);
         if (e2->k == VRELOCABLE && GET_OPCODE(getcode(fs, e2)) == OP_CONCAT) {
           lua_assert(e1->u.info == GETARG_B(getcode(fs, e2))-1);
           freeexp(fs, e1);
           SETARG_B(getcode(fs, e2), e1->u.info);
           e1->k = VRELOCABLE; e1->u.info = e2->u.info;
         }
         else {
           luaK_exp2nextreg(fs, e2);  /* operand must be on the 'stack' */
           codearith(fs, OP_CONCAT, e1, e2, line);
         }
         break;
       }
       case OPR_ADD: case OPR_SUB: case OPR_MUL: case OPR_DIV:
       case OPR_MOD: case OPR_POW: {
         codearith(fs, cast(OpCode, op - OPR_ADD + OP_ADD), e1, e2, line);
         break;
       }
       case OPR_EQ: case OPR_LT: case OPR_LE: {
         codecomp(fs, cast(OpCode, op - OPR_EQ + OP_EQ), 1, e1, e2);
         break;
       }
       case OPR_NE: case OPR_GT: case OPR_GE: {
         codecomp(fs, cast(OpCode, op - OPR_NE + OP_EQ), 0, e1, e2);
         break;
       }
       default: lua_assert(0);
     }
   }
   
   
   void luaK_fixline (FuncState *fs, int line) {
     fs->f->lineinfo[fs->pc - 1] = line;
   }
   
   
   void luaK_setlist (FuncState *fs, int base, int nelems, int tostore) {
     int c =  (nelems - 1)/LFIELDS_PER_FLUSH + 1;
     int b = (tostore == LUA_MULTRET) ? 0 : tostore;
     lua_assert(tostore != 0);
     if (c <= MAXARG_C)
       luaK_codeABC(fs, OP_SETLIST, base, b, c);
     else if (c <= MAXARG_Ax) {
       luaK_codeABC(fs, OP_SETLIST, base, b, 0);
       codeextraarg(fs, c);
     }
     else
       luaX_syntaxerror(fs->ls, "constructor too long");
     fs->freereg = base + 1;  /* free registers with list values */
   }

Cache object: 7da107e2ddd3203613c96bc3d58ee98f