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
840