1 | /* |
2 | ** $Id: lcode.c,v 2.25.1.5 2011/01/31 14:53:16 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 VJMP: { |
548 | invertjump(fs, e); |
549 | pc = e->u.s.info; |
550 | break; |
551 | } |
552 | default: { |
553 | pc = jumponcond(fs, e, 0); |
554 | break; |
555 | } |
556 | } |
557 | luaK_concat(fs, &e->f, pc); /* insert last jump in `f' list */ |
558 | luaK_patchtohere(fs, e->t); |
559 | e->t = NO_JUMP; |
560 | } |
561 | |
562 | |
563 | static void luaK_goiffalse (FuncState *fs, expdesc *e) { |
564 | int pc; /* pc of last jump */ |
565 | luaK_dischargevars(fs, e); |
566 | switch (e->k) { |
567 | case VNIL: case VFALSE: { |
568 | pc = NO_JUMP; /* always false; do nothing */ |
569 | break; |
570 | } |
571 | case VJMP: { |
572 | pc = e->u.s.info; |
573 | break; |
574 | } |
575 | default: { |
576 | pc = jumponcond(fs, e, 1); |
577 | break; |
578 | } |
579 | } |
580 | luaK_concat(fs, &e->t, pc); /* insert last jump in `t' list */ |
581 | luaK_patchtohere(fs, e->f); |
582 | e->f = NO_JUMP; |
583 | } |
584 | |
585 | |
586 | static void codenot (FuncState *fs, expdesc *e) { |
587 | luaK_dischargevars(fs, e); |
588 | switch (e->k) { |
589 | case VNIL: case VFALSE: { |
590 | e->k = VTRUE; |
591 | break; |
592 | } |
593 | case VK: case VKNUM: case VTRUE: { |
594 | e->k = VFALSE; |
595 | break; |
596 | } |
597 | case VJMP: { |
598 | invertjump(fs, e); |
599 | break; |
600 | } |
601 | case VRELOCABLE: |
602 | case VNONRELOC: { |
603 | discharge2anyreg(fs, e); |
604 | freeexp(fs, e); |
605 | e->u.s.info = luaK_codeABC(fs, OP_NOT, 0, e->u.s.info, 0); |
606 | e->k = VRELOCABLE; |
607 | break; |
608 | } |
609 | default: { |
610 | lua_assert(0); /* cannot happen */ |
611 | break; |
612 | } |
613 | } |
614 | /* interchange true and false lists */ |
615 | { int temp = e->f; e->f = e->t; e->t = temp; } |
616 | removevalues(fs, e->f); |
617 | removevalues(fs, e->t); |
618 | } |
619 | |
620 | |
621 | void luaK_indexed (FuncState *fs, expdesc *t, expdesc *k) { |
622 | t->u.s.aux = luaK_exp2RK(fs, k); |
623 | t->k = VINDEXED; |
624 | } |
625 | |
626 | |
627 | static int constfolding (OpCode op, expdesc *e1, expdesc *e2) { |
628 | lua_Number v1, v2, r; |
629 | if (!isnumeral(e1) || !isnumeral(e2)) return 0; |
630 | v1 = e1->u.nval; |
631 | v2 = e2->u.nval; |
632 | switch (op) { |
633 | case OP_ADD: r = luai_numadd(v1, v2); break; |
634 | case OP_SUB: r = luai_numsub(v1, v2); break; |
635 | case OP_MUL: r = luai_nummul(v1, v2); break; |
636 | case OP_DIV: |
637 | if (v2 == 0) return 0; /* do not attempt to divide by 0 */ |
638 | r = luai_numdiv(v1, v2); break; |
639 | case OP_MOD: |
640 | if (v2 == 0) return 0; /* do not attempt to divide by 0 */ |
641 | r = luai_nummod(v1, v2); break; |
642 | case OP_POW: r = luai_numpow(v1, v2); break; |
643 | case OP_UNM: r = luai_numunm(v1); break; |
644 | case OP_LEN: return 0; /* no constant folding for 'len' */ |
645 | default: lua_assert(0); r = 0; break; |
646 | } |
647 | if (luai_numisnan(r)) return 0; /* do not attempt to produce NaN */ |
648 | e1->u.nval = r; |
649 | return 1; |
650 | } |
651 | |
652 | |
653 | static void codearith (FuncState *fs, OpCode op, expdesc *e1, expdesc *e2) { |
654 | if (constfolding(op, e1, e2)) |
655 | return; |
656 | else { |
657 | int o2 = (op != OP_UNM && op != OP_LEN) ? luaK_exp2RK(fs, e2) : 0; |
658 | int o1 = luaK_exp2RK(fs, e1); |
659 | if (o1 > o2) { |
660 | freeexp(fs, e1); |
661 | freeexp(fs, e2); |
662 | } |
663 | else { |
664 | freeexp(fs, e2); |
665 | freeexp(fs, e1); |
666 | } |
667 | e1->u.s.info = luaK_codeABC(fs, op, 0, o1, o2); |
668 | e1->k = VRELOCABLE; |
669 | } |
670 | } |
671 | |
672 | |
673 | static void codecomp (FuncState *fs, OpCode op, int cond, expdesc *e1, |
674 | expdesc *e2) { |
675 | int o1 = luaK_exp2RK(fs, e1); |
676 | int o2 = luaK_exp2RK(fs, e2); |
677 | freeexp(fs, e2); |
678 | freeexp(fs, e1); |
679 | if (cond == 0 && op != OP_EQ) { |
680 | int temp; /* exchange args to replace by `<' or `<=' */ |
681 | temp = o1; o1 = o2; o2 = temp; /* o1 <==> o2 */ |
682 | cond = 1; |
683 | } |
684 | e1->u.s.info = condjump(fs, op, cond, o1, o2); |
685 | e1->k = VJMP; |
686 | } |
687 | |
688 | |
689 | void luaK_prefix (FuncState *fs, UnOpr op, expdesc *e) { |
690 | expdesc e2; |
691 | e2.t = e2.f = NO_JUMP; e2.k = VKNUM; e2.u.nval = 0; |
692 | switch (op) { |
693 | case OPR_MINUS: { |
694 | if (!isnumeral(e)) |
695 | luaK_exp2anyreg(fs, e); /* cannot operate on non-numeric constants */ |
696 | codearith(fs, OP_UNM, e, &e2); |
697 | break; |
698 | } |
699 | case OPR_NOT: codenot(fs, e); break; |
700 | case OPR_LEN: { |
701 | luaK_exp2anyreg(fs, e); /* cannot operate on constants */ |
702 | codearith(fs, OP_LEN, e, &e2); |
703 | break; |
704 | } |
705 | default: lua_assert(0); |
706 | } |
707 | } |
708 | |
709 | |
710 | void luaK_infix (FuncState *fs, BinOpr op, expdesc *v) { |
711 | switch (op) { |
712 | case OPR_AND: { |
713 | luaK_goiftrue(fs, v); |
714 | break; |
715 | } |
716 | case OPR_OR: { |
717 | luaK_goiffalse(fs, v); |
718 | break; |
719 | } |
720 | case OPR_CONCAT: { |
721 | luaK_exp2nextreg(fs, v); /* operand must be on the `stack' */ |
722 | break; |
723 | } |
724 | case OPR_ADD: case OPR_SUB: case OPR_MUL: case OPR_DIV: |
725 | case OPR_MOD: case OPR_POW: { |
726 | if (!isnumeral(v)) luaK_exp2RK(fs, v); |
727 | break; |
728 | } |
729 | default: { |
730 | luaK_exp2RK(fs, v); |
731 | break; |
732 | } |
733 | } |
734 | } |
735 | |
736 | |
737 | void luaK_posfix (FuncState *fs, BinOpr op, expdesc *e1, expdesc *e2) { |
738 | switch (op) { |
739 | case OPR_AND: { |
740 | lua_assert(e1->t == NO_JUMP); /* list must be closed */ |
741 | luaK_dischargevars(fs, e2); |
742 | luaK_concat(fs, &e2->f, e1->f); |
743 | *e1 = *e2; |
744 | break; |
745 | } |
746 | case OPR_OR: { |
747 | lua_assert(e1->f == NO_JUMP); /* list must be closed */ |
748 | luaK_dischargevars(fs, e2); |
749 | luaK_concat(fs, &e2->t, e1->t); |
750 | *e1 = *e2; |
751 | break; |
752 | } |
753 | case OPR_CONCAT: { |
754 | luaK_exp2val(fs, e2); |
755 | if (e2->k == VRELOCABLE && GET_OPCODE(getcode(fs, e2)) == OP_CONCAT) { |
756 | lua_assert(e1->u.s.info == GETARG_B(getcode(fs, e2))-1); |
757 | freeexp(fs, e1); |
758 | SETARG_B(getcode(fs, e2), e1->u.s.info); |
759 | e1->k = VRELOCABLE; e1->u.s.info = e2->u.s.info; |
760 | } |
761 | else { |
762 | luaK_exp2nextreg(fs, e2); /* operand must be on the 'stack' */ |
763 | codearith(fs, OP_CONCAT, e1, e2); |
764 | } |
765 | break; |
766 | } |
767 | case OPR_ADD: codearith(fs, OP_ADD, e1, e2); break; |
768 | case OPR_SUB: codearith(fs, OP_SUB, e1, e2); break; |
769 | case OPR_MUL: codearith(fs, OP_MUL, e1, e2); break; |
770 | case OPR_DIV: codearith(fs, OP_DIV, e1, e2); break; |
771 | case OPR_MOD: codearith(fs, OP_MOD, e1, e2); break; |
772 | case OPR_POW: codearith(fs, OP_POW, e1, e2); break; |
773 | case OPR_EQ: codecomp(fs, OP_EQ, 1, e1, e2); break; |
774 | case OPR_NE: codecomp(fs, OP_EQ, 0, e1, e2); break; |
775 | case OPR_LT: codecomp(fs, OP_LT, 1, e1, e2); break; |
776 | case OPR_LE: codecomp(fs, OP_LE, 1, e1, e2); break; |
777 | case OPR_GT: codecomp(fs, OP_LT, 0, e1, e2); break; |
778 | case OPR_GE: codecomp(fs, OP_LE, 0, e1, e2); break; |
779 | default: lua_assert(0); |
780 | } |
781 | } |
782 | |
783 | |
784 | void luaK_fixline (FuncState *fs, int line) { |
785 | fs->f->lineinfo[fs->pc - 1] = line; |
786 | } |
787 | |
788 | |
789 | static int luaK_code (FuncState *fs, Instruction i, int line) { |
790 | Proto *f = fs->f; |
791 | dischargejpc(fs); /* `pc' will change */ |
792 | /* put new instruction in code array */ |
793 | luaM_growvector(fs->L, f->code, fs->pc, f->sizecode, Instruction, |
794 | MAX_INT, "code size overflow" ); |
795 | f->code[fs->pc] = i; |
796 | /* save corresponding line information */ |
797 | luaM_growvector(fs->L, f->lineinfo, fs->pc, f->sizelineinfo, int, |
798 | MAX_INT, "code size overflow" ); |
799 | f->lineinfo[fs->pc] = line; |
800 | return fs->pc++; |
801 | } |
802 | |
803 | |
804 | int luaK_codeABC (FuncState *fs, OpCode o, int a, int b, int c) { |
805 | lua_assert(getOpMode(o) == iABC); |
806 | lua_assert(getBMode(o) != OpArgN || b == 0); |
807 | lua_assert(getCMode(o) != OpArgN || c == 0); |
808 | return luaK_code(fs, CREATE_ABC(o, a, b, c), fs->ls->lastline); |
809 | } |
810 | |
811 | |
812 | int luaK_codeABx (FuncState *fs, OpCode o, int a, unsigned int bc) { |
813 | lua_assert(getOpMode(o) == iABx || getOpMode(o) == iAsBx); |
814 | lua_assert(getCMode(o) == OpArgN); |
815 | return luaK_code(fs, CREATE_ABx(o, a, bc), fs->ls->lastline); |
816 | } |
817 | |
818 | |
819 | void luaK_setlist (FuncState *fs, int base, int nelems, int tostore) { |
820 | int c = (nelems - 1)/LFIELDS_PER_FLUSH + 1; |
821 | int b = (tostore == LUA_MULTRET) ? 0 : tostore; |
822 | lua_assert(tostore != 0); |
823 | if (c <= MAXARG_C) |
824 | luaK_codeABC(fs, OP_SETLIST, base, b, c); |
825 | else { |
826 | luaK_codeABC(fs, OP_SETLIST, base, b, 0); |
827 | luaK_code(fs, cast(Instruction, c), fs->ls->lastline); |
828 | } |
829 | fs->freereg = base + 1; /* free registers with list values */ |
830 | } |
831 | |
832 | |