root/src/lua-5.1.3/src/lcode.c

Revision 5c8778c4361d2ad3adc94ef98d804c6fa9e6ba7c, 20.8 kB (checked in by Theo Schlossnagle <jesus@omniti.com>, 10 years ago)

import lua... I'd like to write checkers in lua

  • Property mode set to 100644
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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
30 static int isnumeral(expdesc *e) {
31   return (e->k == VKNUM && e->t == NO_JUMP && e->f == NO_JUMP);
32 }
33
34
35 void 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
59 int 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
69 void luaK_ret (FuncState *fs, int first, int nret) {
70   luaK_codeABC(fs, OP_RETURN, first, nret+1, 0);
71 }
72
73
74 static 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
80 static 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 */
94 int luaK_getlabel (FuncState *fs) {
95   fs->lasttarget = fs->pc;
96   return fs->pc;
97 }
98
99
100 static 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
109 static 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 */
122 static 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
131 static 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
144 static void removevalues (FuncState *fs, int list) {
145   for (; list != NO_JUMP; list = getjump(fs, list))
146       patchtestreg(fs, list, NO_REG);
147 }
148
149
150 static 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
163 static void dischargejpc (FuncState *fs) {
164   patchlistaux(fs, fs->jpc, fs->pc, NO_REG, fs->pc);
165   fs->jpc = NO_JUMP;
166 }
167
168
169 void 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
179 void luaK_patchtohere (FuncState *fs, int list) {
180   luaK_getlabel(fs);
181   luaK_concat(fs, &fs->jpc, list);
182 }
183
184
185 void 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
199 void 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
209 void luaK_reserveregs (FuncState *fs, int n) {
210   luaK_checkstack(fs, n);
211   fs->freereg += n;
212 }
213
214
215 static 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
223 static void freeexp (FuncState *fs, expdesc *e) {
224   if (e->k == VNONRELOC)
225     freereg(fs, e->u.s.info);
226 }
227
228
229 static 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
250 int luaK_stringK (FuncState *fs, TString *s) {
251   TValue o;
252   setsvalue(fs->L, &o, s);
253   return addk(fs, &o, &o);
254 }
255
256
257 int luaK_numberK (FuncState *fs, lua_Number r) {
258   TValue o;
259   setnvalue(&o, r);
260   return addk(fs, &o, &o);
261 }
262
263
264 static int boolK (FuncState *fs, int b) {
265   TValue o;
266   setbvalue(&o, b);
267   return addk(fs, &o, &o);
268 }
269
270
271 static 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
280 void 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
292 void 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
304 void 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
337 static 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
343 static 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
382 static 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
390 static 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
414 void 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
422 int 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
436 void 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
444 int 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
472 void 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
503 void 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
516 static 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
524 static 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
539 void 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
567 static 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
594 static 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
629 void luaK_indexed (FuncState *fs, expdesc *t, expdesc *k) {
630   t->u.s.aux = luaK_exp2RK(fs, k);
631   t->k = VINDEXED;
632 }
633
634
635 static 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
661 static 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
681 static 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
697 void 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
718 void 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
745 void 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
792 void luaK_fixline (FuncState *fs, int line) {
793   fs->f->lineinfo[fs->pc - 1] = line;
794 }
795
796
797 static 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
812 int 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
820 int 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
827 void 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
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