/script_binding/lua/lua/lcode.c

  1/*
  2** $Id: lcode.c,v 2.25.1.3 2007/12/28 15:32:23 roberto Exp $
  3** Code generator for Lua
  4** See Copyright Notice in lua.h
  5*/
  6
  7
  8#include <stdlib.h>
  9
 10#define lcode_c
 11#define LUA_CORE
 12
 13#include "lua.h"
 14
 15#include "lcode.h"
 16#include "ldebug.h"
 17#include "ldo.h"
 18#include "lgc.h"
 19#include "llex.h"
 20#include "lmem.h"
 21#include "lobject.h"
 22#include "lopcodes.h"
 23#include "lparser.h"
 24#include "ltable.h"
 25
 26
 27#define hasjumps(e)	((e)->t != (e)->f)
 28
 29
 30static int isnumeral(expdesc *e) {
 31  return (e->k == VKNUM && e->t == NO_JUMP && e->f == NO_JUMP);
 32}
 33
 34
 35void luaK_nil (FuncState *fs, int from, int n) {
 36  Instruction *previous;
 37  if (fs->pc > fs->lasttarget) {  /* no jumps to current position? */
 38    if (fs->pc == 0) {  /* function start? */
 39      if (from >= fs->nactvar)
 40        return;  /* positions are already clean */
 41    }
 42    else {
 43      previous = &fs->f->code[fs->pc-1];
 44      if (GET_OPCODE(*previous) == OP_LOADNIL) {
 45        int pfrom = GETARG_A(*previous);
 46        int pto = GETARG_B(*previous);
 47        if (pfrom <= from && from <= pto+1) {  /* can connect both? */
 48          if (from+n-1 > pto)
 49            SETARG_B(*previous, from+n-1);
 50          return;
 51        }
 52      }
 53    }
 54  }
 55  luaK_codeABC(fs, OP_LOADNIL, from, from+n-1, 0);  /* else no optimization */
 56}
 57
 58
 59int luaK_jump (FuncState *fs) {
 60  int jpc = fs->jpc;  /* save list of jumps to here */
 61  int j;
 62  fs->jpc = NO_JUMP;
 63  j = luaK_codeAsBx(fs, OP_JMP, 0, NO_JUMP);
 64  luaK_concat(fs, &j, jpc);  /* keep them on hold */
 65  return j;
 66}
 67
 68
 69void luaK_ret (FuncState *fs, int first, int nret) {
 70  luaK_codeABC(fs, OP_RETURN, first, nret+1, 0);
 71}
 72
 73
 74static int condjump (FuncState *fs, OpCode op, int A, int B, int C) {
 75  luaK_codeABC(fs, op, A, B, C);
 76  return luaK_jump(fs);
 77}
 78
 79
 80static void fixjump (FuncState *fs, int pc, int dest) {
 81  Instruction *jmp = &fs->f->code[pc];
 82  int offset = dest-(pc+1);
 83  lua_assert(dest != NO_JUMP);
 84  if (abs(offset) > MAXARG_sBx)
 85    luaX_syntaxerror(fs->ls, "control structure too long");
 86  SETARG_sBx(*jmp, offset);
 87}
 88
 89
 90/*
 91** returns current `pc' and marks it as a jump target (to avoid wrong
 92** optimizations with consecutive instructions not in the same basic block).
 93*/
 94int luaK_getlabel (FuncState *fs) {
 95  fs->lasttarget = fs->pc;
 96  return fs->pc;
 97}
 98
 99
100static int getjump (FuncState *fs, int pc) {
101  int offset = GETARG_sBx(fs->f->code[pc]);
102  if (offset == NO_JUMP)  /* point to itself represents end of list */
103    return NO_JUMP;  /* end of list */
104  else
105    return (pc+1)+offset;  /* turn offset into absolute position */
106}
107
108
109static Instruction *getjumpcontrol (FuncState *fs, int pc) {
110  Instruction *pi = &fs->f->code[pc];
111  if (pc >= 1 && testTMode(GET_OPCODE(*(pi-1))))
112    return pi-1;
113  else
114    return pi;
115}
116
117
118/*
119** check whether list has any jump that do not produce a value
120** (or produce an inverted value)
121*/
122static int need_value (FuncState *fs, int list) {
123  for (; list != NO_JUMP; list = getjump(fs, list)) {
124    Instruction i = *getjumpcontrol(fs, list);
125    if (GET_OPCODE(i) != OP_TESTSET) return 1;
126  }
127  return 0;  /* not found */
128}
129
130
131static int patchtestreg (FuncState *fs, int node, int reg) {
132  Instruction *i = getjumpcontrol(fs, node);
133  if (GET_OPCODE(*i) != OP_TESTSET)
134    return 0;  /* cannot patch other instructions */
135  if (reg != NO_REG && reg != GETARG_B(*i))
136    SETARG_A(*i, reg);
137  else  /* no register to put value or register already has the value */
138    *i = CREATE_ABC(OP_TEST, GETARG_B(*i), 0, GETARG_C(*i));
139
140  return 1;
141}
142
143
144static void removevalues (FuncState *fs, int list) {
145  for (; list != NO_JUMP; list = getjump(fs, list))
146      patchtestreg(fs, list, NO_REG);
147}
148
149
150static void patchlistaux (FuncState *fs, int list, int vtarget, int reg,
151                          int dtarget) {
152  while (list != NO_JUMP) {
153    int next = getjump(fs, list);
154    if (patchtestreg(fs, list, reg))
155      fixjump(fs, list, vtarget);
156    else
157      fixjump(fs, list, dtarget);  /* jump to default target */
158    list = next;
159  }
160}
161
162
163static void dischargejpc (FuncState *fs) {
164  patchlistaux(fs, fs->jpc, fs->pc, NO_REG, fs->pc);
165  fs->jpc = NO_JUMP;
166}
167
168
169void luaK_patchlist (FuncState *fs, int list, int target) {
170  if (target == fs->pc)
171    luaK_patchtohere(fs, list);
172  else {
173    lua_assert(target < fs->pc);
174    patchlistaux(fs, list, target, NO_REG, target);
175  }
176}
177
178
179void luaK_patchtohere (FuncState *fs, int list) {
180  luaK_getlabel(fs);
181  luaK_concat(fs, &fs->jpc, list);
182}
183
184
185void luaK_concat (FuncState *fs, int *l1, int l2) {
186  if (l2 == NO_JUMP) return;
187  else if (*l1 == NO_JUMP)
188    *l1 = l2;
189  else {
190    int list = *l1;
191    int next;
192    while ((next = getjump(fs, list)) != NO_JUMP)  /* find last element */
193      list = next;
194    fixjump(fs, list, l2);
195  }
196}
197
198
199void luaK_checkstack (FuncState *fs, int n) {
200  int newstack = fs->freereg + n;
201  if (newstack > fs->f->maxstacksize) {
202    if (newstack >= MAXSTACK)
203      luaX_syntaxerror(fs->ls, "function or expression too complex");
204    fs->f->maxstacksize = cast_byte(newstack);
205  }
206}
207
208
209void luaK_reserveregs (FuncState *fs, int n) {
210  luaK_checkstack(fs, n);
211  fs->freereg += n;
212}
213
214
215static void freereg (FuncState *fs, int reg) {
216  if (!ISK(reg) && reg >= fs->nactvar) {
217    fs->freereg--;
218    lua_assert(reg == fs->freereg);
219  }
220}
221
222
223static void freeexp (FuncState *fs, expdesc *e) {
224  if (e->k == VNONRELOC)
225    freereg(fs, e->u.s.info);
226}
227
228
229static int addk (FuncState *fs, TValue *k, TValue *v) {
230  lua_State *L = fs->L;
231  TValue *idx = luaH_set(L, fs->h, k);
232  Proto *f = fs->f;
233  int oldsize = f->sizek;
234  if (ttisnumber(idx)) {
235    lua_assert(luaO_rawequalObj(&fs->f->k[cast_int(nvalue(idx))], v));
236    return cast_int(nvalue(idx));
237  }
238  else {  /* constant not found; create a new entry */
239    setnvalue(idx, cast_num(fs->nk));
240    luaM_growvector(L, f->k, fs->nk, f->sizek, TValue,
241                    MAXARG_Bx, "constant table overflow");
242    while (oldsize < f->sizek) setnilvalue(&f->k[oldsize++]);
243    setobj(L, &f->k[fs->nk], v);
244    luaC_barrier(L, f, v);
245    return fs->nk++;
246  }
247}
248
249
250int luaK_stringK (FuncState *fs, TString *s) {
251  TValue o;
252  setsvalue(fs->L, &o, s);
253  return addk(fs, &o, &o);
254}
255
256
257int luaK_numberK (FuncState *fs, lua_Number r) {
258  TValue o;
259  setnvalue(&o, r);
260  return addk(fs, &o, &o);
261}
262
263
264static int boolK (FuncState *fs, int b) {
265  TValue o;
266  setbvalue(&o, b);
267  return addk(fs, &o, &o);
268}
269
270
271static int nilK (FuncState *fs) {
272  TValue k, v;
273  setnilvalue(&v);
274  /* cannot use nil as key; instead use table itself to represent nil */
275  sethvalue(fs->L, &k, fs->h);
276  return addk(fs, &k, &v);
277}
278
279
280void luaK_setreturns (FuncState *fs, expdesc *e, int nresults) {
281  if (e->k == VCALL) {  /* expression is an open function call? */
282    SETARG_C(getcode(fs, e), nresults+1);
283  }
284  else if (e->k == VVARARG) {
285    SETARG_B(getcode(fs, e), nresults+1);
286    SETARG_A(getcode(fs, e), fs->freereg);
287    luaK_reserveregs(fs, 1);
288  }
289}
290
291
292void luaK_setoneret (FuncState *fs, expdesc *e) {
293  if (e->k == VCALL) {  /* expression is an open function call? */
294    e->k = VNONRELOC;
295    e->u.s.info = GETARG_A(getcode(fs, e));
296  }
297  else if (e->k == VVARARG) {
298    SETARG_B(getcode(fs, e), 2);
299    e->k = VRELOCABLE;  /* can relocate its simple result */
300  }
301}
302
303
304void luaK_dischargevars (FuncState *fs, expdesc *e) {
305  switch (e->k) {
306    case VLOCAL: {
307      e->k = VNONRELOC;
308      break;
309    }
310    case VUPVAL: {
311      e->u.s.info = luaK_codeABC(fs, OP_GETUPVAL, 0, e->u.s.info, 0);
312      e->k = VRELOCABLE;
313      break;
314    }
315    case VGLOBAL: {
316      e->u.s.info = luaK_codeABx(fs, OP_GETGLOBAL, 0, e->u.s.info);
317      e->k = VRELOCABLE;
318      break;
319    }
320    case VINDEXED: {
321      freereg(fs, e->u.s.aux);
322      freereg(fs, e->u.s.info);
323      e->u.s.info = luaK_codeABC(fs, OP_GETTABLE, 0, e->u.s.info, e->u.s.aux);
324      e->k = VRELOCABLE;
325      break;
326    }
327    case VVARARG:
328    case VCALL: {
329      luaK_setoneret(fs, e);
330      break;
331    }
332    default: break;  /* there is one value available (somewhere) */
333  }
334}
335
336
337static int code_label (FuncState *fs, int A, int b, int jump) {
338  luaK_getlabel(fs);  /* those instructions may be jump targets */
339  return luaK_codeABC(fs, OP_LOADBOOL, A, b, jump);
340}
341
342
343static void discharge2reg (FuncState *fs, expdesc *e, int reg) {
344  luaK_dischargevars(fs, e);
345  switch (e->k) {
346    case VNIL: {
347      luaK_nil(fs, reg, 1);
348      break;
349    }
350    case VFALSE:  case VTRUE: {
351      luaK_codeABC(fs, OP_LOADBOOL, reg, e->k == VTRUE, 0);
352      break;
353    }
354    case VK: {
355      luaK_codeABx(fs, OP_LOADK, reg, e->u.s.info);
356      break;
357    }
358    case VKNUM: {
359      luaK_codeABx(fs, OP_LOADK, reg, luaK_numberK(fs, e->u.nval));
360      break;
361    }
362    case VRELOCABLE: {
363      Instruction *pc = &getcode(fs, e);
364      SETARG_A(*pc, reg);
365      break;
366    }
367    case VNONRELOC: {
368      if (reg != e->u.s.info)
369        luaK_codeABC(fs, OP_MOVE, reg, e->u.s.info, 0);
370      break;
371    }
372    default: {
373      lua_assert(e->k == VVOID || e->k == VJMP);
374      return;  /* nothing to do... */
375    }
376  }
377  e->u.s.info = reg;
378  e->k = VNONRELOC;
379}
380
381
382static void discharge2anyreg (FuncState *fs, expdesc *e) {
383  if (e->k != VNONRELOC) {
384    luaK_reserveregs(fs, 1);
385    discharge2reg(fs, e, fs->freereg-1);
386  }
387}
388
389
390static void exp2reg (FuncState *fs, expdesc *e, int reg) {
391  discharge2reg(fs, e, reg);
392  if (e->k == VJMP)
393    luaK_concat(fs, &e->t, e->u.s.info);  /* put this jump in `t' list */
394  if (hasjumps(e)) {
395    int final;  /* position after whole expression */
396    int p_f = NO_JUMP;  /* position of an eventual LOAD false */
397    int p_t = NO_JUMP;  /* position of an eventual LOAD true */
398    if (need_value(fs, e->t) || need_value(fs, e->f)) {
399      int fj = (e->k == VJMP) ? NO_JUMP : luaK_jump(fs);
400      p_f = code_label(fs, reg, 0, 1);
401      p_t = code_label(fs, reg, 1, 0);
402      luaK_patchtohere(fs, fj);
403    }
404    final = luaK_getlabel(fs);
405    patchlistaux(fs, e->f, final, reg, p_f);
406    patchlistaux(fs, e->t, final, reg, p_t);
407  }
408  e->f = e->t = NO_JUMP;
409  e->u.s.info = reg;
410  e->k = VNONRELOC;
411}
412
413
414void luaK_exp2nextreg (FuncState *fs, expdesc *e) {
415  luaK_dischargevars(fs, e);
416  freeexp(fs, e);
417  luaK_reserveregs(fs, 1);
418  exp2reg(fs, e, fs->freereg - 1);
419}
420
421
422int luaK_exp2anyreg (FuncState *fs, expdesc *e) {
423  luaK_dischargevars(fs, e);
424  if (e->k == VNONRELOC) {
425    if (!hasjumps(e)) return e->u.s.info;  /* exp is already in a register */
426    if (e->u.s.info >= fs->nactvar) {  /* reg. is not a local? */
427      exp2reg(fs, e, e->u.s.info);  /* put value on it */
428      return e->u.s.info;
429    }
430  }
431  luaK_exp2nextreg(fs, e);  /* default */
432  return e->u.s.info;
433}
434
435
436void luaK_exp2val (FuncState *fs, expdesc *e) {
437  if (hasjumps(e))
438    luaK_exp2anyreg(fs, e);
439  else
440    luaK_dischargevars(fs, e);
441}
442
443
444int luaK_exp2RK (FuncState *fs, expdesc *e) {
445  luaK_exp2val(fs, e);
446  switch (e->k) {
447    case VKNUM:
448    case VTRUE:
449    case VFALSE:
450    case VNIL: {
451      if (fs->nk <= MAXINDEXRK) {  /* constant fit in RK operand? */
452        e->u.s.info = (e->k == VNIL)  ? nilK(fs) :
453                      (e->k == VKNUM) ? luaK_numberK(fs, e->u.nval) :
454                                        boolK(fs, (e->k == VTRUE));
455        e->k = VK;
456        return RKASK(e->u.s.info);
457      }
458      else break;
459    }
460    case VK: {
461      if (e->u.s.info <= MAXINDEXRK)  /* constant fit in argC? */
462        return RKASK(e->u.s.info);
463      else break;
464    }
465    default: break;
466  }
467  /* not a constant in the right range: put it in a register */
468  return luaK_exp2anyreg(fs, e);
469}
470
471
472void luaK_storevar (FuncState *fs, expdesc *var, expdesc *ex) {
473  switch (var->k) {
474    case VLOCAL: {
475      freeexp(fs, ex);
476      exp2reg(fs, ex, var->u.s.info);
477      return;
478    }
479    case VUPVAL: {
480      int e = luaK_exp2anyreg(fs, ex);
481      luaK_codeABC(fs, OP_SETUPVAL, e, var->u.s.info, 0);
482      break;
483    }
484    case VGLOBAL: {
485      int e = luaK_exp2anyreg(fs, ex);
486      luaK_codeABx(fs, OP_SETGLOBAL, e, var->u.s.info);
487      break;
488    }
489    case VINDEXED: {
490      int e = luaK_exp2RK(fs, ex);
491      luaK_codeABC(fs, OP_SETTABLE, var->u.s.info, var->u.s.aux, e);
492      break;
493    }
494    default: {
495      lua_assert(0);  /* invalid var kind to store */
496      break;
497    }
498  }
499  freeexp(fs, ex);
500}
501
502
503void luaK_self (FuncState *fs, expdesc *e, expdesc *key) {
504  int func;
505  luaK_exp2anyreg(fs, e);
506  freeexp(fs, e);
507  func = fs->freereg;
508  luaK_reserveregs(fs, 2);
509  luaK_codeABC(fs, OP_SELF, func, e->u.s.info, luaK_exp2RK(fs, key));
510  freeexp(fs, key);
511  e->u.s.info = func;
512  e->k = VNONRELOC;
513}
514
515
516static void invertjump (FuncState *fs, expdesc *e) {
517  Instruction *pc = getjumpcontrol(fs, e->u.s.info);
518  lua_assert(testTMode(GET_OPCODE(*pc)) && GET_OPCODE(*pc) != OP_TESTSET &&
519                                           GET_OPCODE(*pc) != OP_TEST);
520  SETARG_A(*pc, !(GETARG_A(*pc)));
521}
522
523
524static int jumponcond (FuncState *fs, expdesc *e, int cond) {
525  if (e->k == VRELOCABLE) {
526    Instruction ie = getcode(fs, e);
527    if (GET_OPCODE(ie) == OP_NOT) {
528      fs->pc--;  /* remove previous OP_NOT */
529      return condjump(fs, OP_TEST, GETARG_B(ie), 0, !cond);
530    }
531    /* else go through */
532  }
533  discharge2anyreg(fs, e);
534  freeexp(fs, e);
535  return condjump(fs, OP_TESTSET, NO_REG, e->u.s.info, cond);
536}
537
538
539void luaK_goiftrue (FuncState *fs, expdesc *e) {
540  int pc;  /* pc of last jump */
541  luaK_dischargevars(fs, e);
542  switch (e->k) {
543    case VK: case VKNUM: case VTRUE: {
544      pc = NO_JUMP;  /* always true; do nothing */
545      break;
546    }
547    case VFALSE: {
548      pc = luaK_jump(fs);  /* always jump */
549      break;
550    }
551    case VJMP: {
552      invertjump(fs, e);
553      pc = e->u.s.info;
554      break;
555    }
556    default: {
557      pc = jumponcond(fs, e, 0);
558      break;
559    }
560  }
561  luaK_concat(fs, &e->f, pc);  /* insert last jump in `f' list */
562  luaK_patchtohere(fs, e->t);
563  e->t = NO_JUMP;
564}
565
566
567static void luaK_goiffalse (FuncState *fs, expdesc *e) {
568  int pc;  /* pc of last jump */
569  luaK_dischargevars(fs, e);
570  switch (e->k) {
571    case VNIL: case VFALSE: {
572      pc = NO_JUMP;  /* always false; do nothing */
573      break;
574    }
575    case VTRUE: {
576      pc = luaK_jump(fs);  /* always jump */
577      break;
578    }
579    case VJMP: {
580      pc = e->u.s.info;
581      break;
582    }
583    default: {
584      pc = jumponcond(fs, e, 1);
585      break;
586    }
587  }
588  luaK_concat(fs, &e->t, pc);  /* insert last jump in `t' list */
589  luaK_patchtohere(fs, e->f);
590  e->f = NO_JUMP;
591}
592
593
594static void codenot (FuncState *fs, expdesc *e) {
595  luaK_dischargevars(fs, e);
596  switch (e->k) {
597    case VNIL: case VFALSE: {
598      e->k = VTRUE;
599      break;
600    }
601    case VK: case VKNUM: case VTRUE: {
602      e->k = VFALSE;
603      break;
604    }
605    case VJMP: {
606      invertjump(fs, e);
607      break;
608    }
609    case VRELOCABLE:
610    case VNONRELOC: {
611      discharge2anyreg(fs, e);
612      freeexp(fs, e);
613      e->u.s.info = luaK_codeABC(fs, OP_NOT, 0, e->u.s.info, 0);
614      e->k = VRELOCABLE;
615      break;
616    }
617    default: {
618      lua_assert(0);  /* cannot happen */
619      break;
620    }
621  }
622  /* interchange true and false lists */
623  { int temp = e->f; e->f = e->t; e->t = temp; }
624  removevalues(fs, e->f);
625  removevalues(fs, e->t);
626}
627
628
629void luaK_indexed (FuncState *fs, expdesc *t, expdesc *k) {
630  t->u.s.aux = luaK_exp2RK(fs, k);
631  t->k = VINDEXED;
632}
633
634
635static int constfolding (OpCode op, expdesc *e1, expdesc *e2) {
636  lua_Number v1, v2, r;
637  if (!isnumeral(e1) || !isnumeral(e2)) return 0;
638  v1 = e1->u.nval;
639  v2 = e2->u.nval;
640  switch (op) {
641    case OP_ADD: r = luai_numadd(v1, v2); break;
642    case OP_SUB: r = luai_numsub(v1, v2); break;
643    case OP_MUL: r = luai_nummul(v1, v2); break;
644    case OP_DIV:
645      if (v2 == 0) return 0;  /* do not attempt to divide by 0 */
646      r = luai_numdiv(v1, v2); break;
647    case OP_MOD:
648      if (v2 == 0) return 0;  /* do not attempt to divide by 0 */
649      r = luai_nummod(v1, v2); break;
650    case OP_POW: r = luai_numpow(v1, v2); break;
651    case OP_UNM: r = luai_numunm(v1); break;
652    case OP_LEN: return 0;  /* no constant folding for 'len' */
653    default: lua_assert(0); r = 0; break;
654  }
655  if (luai_numisnan(r)) return 0;  /* do not attempt to produce NaN */
656  e1->u.nval = r;
657  return 1;
658}
659
660
661static void codearith (FuncState *fs, OpCode op, expdesc *e1, expdesc *e2) {
662  if (constfolding(op, e1, e2))
663    return;
664  else {
665    int o2 = (op != OP_UNM && op != OP_LEN) ? luaK_exp2RK(fs, e2) : 0;
666    int o1 = luaK_exp2RK(fs, e1);
667    if (o1 > o2) {
668      freeexp(fs, e1);
669      freeexp(fs, e2);
670    }
671    else {
672      freeexp(fs, e2);
673      freeexp(fs, e1);
674    }
675    e1->u.s.info = luaK_codeABC(fs, op, 0, o1, o2);
676    e1->k = VRELOCABLE;
677  }
678}
679
680
681static void codecomp (FuncState *fs, OpCode op, int cond, expdesc *e1,
682                                                          expdesc *e2) {
683  int o1 = luaK_exp2RK(fs, e1);
684  int o2 = luaK_exp2RK(fs, e2);
685  freeexp(fs, e2);
686  freeexp(fs, e1);
687  if (cond == 0 && op != OP_EQ) {
688    int temp;  /* exchange args to replace by `<' or `<=' */
689    temp = o1; o1 = o2; o2 = temp;  /* o1 <==> o2 */
690    cond = 1;
691  }
692  e1->u.s.info = condjump(fs, op, cond, o1, o2);
693  e1->k = VJMP;
694}
695
696
697void luaK_prefix (FuncState *fs, UnOpr op, expdesc *e) {
698  expdesc e2;
699  e2.t = e2.f = NO_JUMP; e2.k = VKNUM; e2.u.nval = 0;
700  switch (op) {
701    case OPR_MINUS: {
702      if (!isnumeral(e))
703        luaK_exp2anyreg(fs, e);  /* cannot operate on non-numeric constants */
704      codearith(fs, OP_UNM, e, &e2);
705      break;
706    }
707    case OPR_NOT: codenot(fs, e); break;
708    case OPR_LEN: {
709      luaK_exp2anyreg(fs, e);  /* cannot operate on constants */
710      codearith(fs, OP_LEN, e, &e2);
711      break;
712    }
713    default: lua_assert(0);
714  }
715}
716
717
718void luaK_infix (FuncState *fs, BinOpr op, expdesc *v) {
719  switch (op) {
720    case OPR_AND: {
721      luaK_goiftrue(fs, v);
722      break;
723    }
724    case OPR_OR: {
725      luaK_goiffalse(fs, v);
726      break;
727    }
728    case OPR_CONCAT: {
729      luaK_exp2nextreg(fs, v);  /* operand must be on the `stack' */
730      break;
731    }
732    case OPR_ADD: case OPR_SUB: case OPR_MUL: case OPR_DIV:
733    case OPR_MOD: case OPR_POW: {
734      if (!isnumeral(v)) luaK_exp2RK(fs, v);
735      break;
736    }
737    default: {
738      luaK_exp2RK(fs, v);
739      break;
740    }
741  }
742}
743
744
745void luaK_posfix (FuncState *fs, BinOpr op, expdesc *e1, expdesc *e2) {
746  switch (op) {
747    case OPR_AND: {
748      lua_assert(e1->t == NO_JUMP);  /* list must be closed */
749      luaK_dischargevars(fs, e2);
750      luaK_concat(fs, &e2->f, e1->f);
751      *e1 = *e2;
752      break;
753    }
754    case OPR_OR: {
755      lua_assert(e1->f == NO_JUMP);  /* list must be closed */
756      luaK_dischargevars(fs, e2);
757      luaK_concat(fs, &e2->t, e1->t);
758      *e1 = *e2;
759      break;
760    }
761    case OPR_CONCAT: {
762      luaK_exp2val(fs, e2);
763      if (e2->k == VRELOCABLE && GET_OPCODE(getcode(fs, e2)) == OP_CONCAT) {
764        lua_assert(e1->u.s.info == GETARG_B(getcode(fs, e2))-1);
765        freeexp(fs, e1);
766        SETARG_B(getcode(fs, e2), e1->u.s.info);
767        e1->k = VRELOCABLE; e1->u.s.info = e2->u.s.info;
768      }
769      else {
770        luaK_exp2nextreg(fs, e2);  /* operand must be on the 'stack' */
771        codearith(fs, OP_CONCAT, e1, e2);
772      }
773      break;
774    }
775    case OPR_ADD: codearith(fs, OP_ADD, e1, e2); break;
776    case OPR_SUB: codearith(fs, OP_SUB, e1, e2); break;
777    case OPR_MUL: codearith(fs, OP_MUL, e1, e2); break;
778    case OPR_DIV: codearith(fs, OP_DIV, e1, e2); break;
779    case OPR_MOD: codearith(fs, OP_MOD, e1, e2); break;
780    case OPR_POW: codearith(fs, OP_POW, e1, e2); break;
781    case OPR_EQ: codecomp(fs, OP_EQ, 1, e1, e2); break;
782    case OPR_NE: codecomp(fs, OP_EQ, 0, e1, e2); break;
783    case OPR_LT: codecomp(fs, OP_LT, 1, e1, e2); break;
784    case OPR_LE: codecomp(fs, OP_LE, 1, e1, e2); break;
785    case OPR_GT: codecomp(fs, OP_LT, 0, e1, e2); break;
786    case OPR_GE: codecomp(fs, OP_LE, 0, e1, e2); break;
787    default: lua_assert(0);
788  }
789}
790
791
792void luaK_fixline (FuncState *fs, int line) {
793  fs->f->lineinfo[fs->pc - 1] = line;
794}
795
796
797static int luaK_code (FuncState *fs, Instruction i, int line) {
798  Proto *f = fs->f;
799  dischargejpc(fs);  /* `pc' will change */
800  /* put new instruction in code array */
801  luaM_growvector(fs->L, f->code, fs->pc, f->sizecode, Instruction,
802                  MAX_INT, "code size overflow");
803  f->code[fs->pc] = i;
804  /* save corresponding line information */
805  luaM_growvector(fs->L, f->lineinfo, fs->pc, f->sizelineinfo, int,
806                  MAX_INT, "code size overflow");
807  f->lineinfo[fs->pc] = line;
808  return fs->pc++;
809}
810
811
812int luaK_codeABC (FuncState *fs, OpCode o, int a, int b, int c) {
813  lua_assert(getOpMode(o) == iABC);
814  lua_assert(getBMode(o) != OpArgN || b == 0);
815  lua_assert(getCMode(o) != OpArgN || c == 0);
816  return luaK_code(fs, CREATE_ABC(o, a, b, c), fs->ls->lastline);
817}
818
819
820int luaK_codeABx (FuncState *fs, OpCode o, int a, unsigned int bc) {
821  lua_assert(getOpMode(o) == iABx || getOpMode(o) == iAsBx);
822  lua_assert(getCMode(o) == OpArgN);
823  return luaK_code(fs, CREATE_ABx(o, a, bc), fs->ls->lastline);
824}
825
826
827void luaK_setlist (FuncState *fs, int base, int nelems, int tostore) {
828  int c =  (nelems - 1)/LFIELDS_PER_FLUSH + 1;
829  int b = (tostore == LUA_MULTRET) ? 0 : tostore;
830  lua_assert(tostore != 0);
831  if (c <= MAXARG_C)
832    luaK_codeABC(fs, OP_SETLIST, base, b, c);
833  else {
834    luaK_codeABC(fs, OP_SETLIST, base, b, 0);
835    luaK_code(fs, cast(Instruction, c), fs->ls->lastline);
836  }
837  fs->freereg = base + 1;  /* free registers with list values */
838}
839