2 ** Lua parser (source code -> bytecode).
3 ** Copyright (C) 2005-2011 Mike Pall. See Copyright Notice in luajit.h
5 ** Major portions taken verbatim or adapted from the Lua interpreter.
6 ** Copyright (C) 1994-2008 Lua.org, PUC-Rio. See Copyright Notice in lua.h
27 #include "lj_vmevent.h"
29 /* -- Parser structures and definitions ----------------------------------- */
31 /* Expression kinds. */
33 /* Constant expressions must be first and in this order: */
37 VKSTR
, /* sval = string value */
38 VKNUM
, /* nval = number value */
40 VKCDATA
, /* nval = cdata value, not treated as a constant expression */
41 /* Non-constant expressions follow: */
42 VLOCAL
, /* info = local register */
43 VUPVAL
, /* info = upvalue index */
44 VGLOBAL
, /* sval = string value */
45 VINDEXED
, /* info = table register, aux = index reg/byte/string const */
46 VJMP
, /* info = instruction PC */
47 VRELOCABLE
, /* info = instruction PC */
48 VNONRELOC
, /* info = result register */
49 VCALL
, /* info = instruction PC, aux = base */
53 /* Expression descriptor. */
54 typedef struct ExpDesc
{
57 uint32_t info
; /* Primary info. */
58 uint32_t aux
; /* Secondary info. */
60 TValue nval
; /* Number value. */
61 GCstr
*sval
; /* String value. */
64 BCPos t
; /* True condition jump list. */
65 BCPos f
; /* False condition jump list. */
68 /* Macros for expressions. */
69 #define expr_hasjump(e) ((e)->t != (e)->f)
71 #define expr_isk(e) ((e)->k <= VKLAST)
72 #define expr_isk_nojump(e) (expr_isk(e) && !expr_hasjump(e))
73 #define expr_isnumk(e) ((e)->k == VKNUM)
74 #define expr_isnumk_nojump(e) (expr_isnumk(e) && !expr_hasjump(e))
75 #define expr_isstrk(e) ((e)->k == VKSTR)
77 #define expr_numtv(e) check_exp(expr_isnumk((e)), &(e)->u.nval)
78 #define expr_numberV(e) numberVnum(expr_numtv((e)))
80 /* Initialize expression. */
81 static LJ_AINLINE
void expr_init(ExpDesc
*e
, ExpKind k
, uint32_t info
)
88 /* Check number constant for +-0. */
89 static int expr_numiszero(ExpDesc
*e
)
91 TValue
*o
= expr_numtv(e
);
92 return tvisint(o
) ? (intV(o
) == 0) : tviszero(o
);
95 /* Per-function linked list of scope blocks. */
96 typedef struct FuncScope
{
97 struct FuncScope
*prev
; /* Link to outer scope. */
98 BCPos breaklist
; /* Jump list for loop breaks. */
99 uint8_t nactvar
; /* Number of active vars outside the scope. */
100 uint8_t upval
; /* Some variable in the scope is an upvalue. */
101 uint8_t isbreakable
; /* Scope is a loop and allows a break. */
104 /* Index into variable stack. */
105 typedef uint16_t VarIndex
;
106 #define LJ_MAX_VSTACK 65536
109 typedef struct UVMap
{
110 VarIndex vidx
; /* Varinfo index. */
111 uint16_t slot
; /* Slot or parent upvalue index. */
114 /* Per-function state. */
115 typedef struct FuncState
{
116 GCtab
*kt
; /* Hash table for constants. */
117 LexState
*ls
; /* Lexer state. */
118 lua_State
*L
; /* Lua state. */
119 FuncScope
*bl
; /* Current scope. */
120 struct FuncState
*prev
; /* Enclosing function. */
121 BCPos pc
; /* Next bytecode position. */
122 BCPos lasttarget
; /* Bytecode position of last jump target. */
123 BCPos jpc
; /* Pending jump list to next bytecode. */
124 BCReg freereg
; /* First free register. */
125 BCReg nactvar
; /* Number of active local variables. */
126 BCReg nkn
, nkgc
; /* Number of lua_Number/GCobj constants */
127 BCLine linedefined
; /* First line of the function definition. */
128 BCInsLine
*bcbase
; /* Base of bytecode stack. */
129 BCPos bclim
; /* Limit of bytecode stack. */
130 MSize vbase
; /* Base of variable stack for this function. */
131 uint8_t flags
; /* Prototype flags. */
132 uint8_t numparams
; /* Number of parameters. */
133 uint8_t framesize
; /* Fixed frame size. */
134 uint8_t nuv
; /* Number of upvalues */
135 VarIndex varmap
[LJ_MAX_LOCVAR
]; /* Map from register to variable idx. */
136 UVMap uvloc
[LJ_MAX_UPVAL
]; /* Map from upvalue to variable idx and slot. */
139 /* Binary and unary operators. ORDER OPR */
140 typedef enum BinOpr
{
141 OPR_ADD
, OPR_SUB
, OPR_MUL
, OPR_DIV
, OPR_MOD
, OPR_POW
, /* ORDER ARITH */
144 OPR_LT
, OPR_GE
, OPR_LE
, OPR_GT
,
149 LJ_STATIC_ASSERT((int)BC_ISGE
-(int)BC_ISLT
== (int)OPR_GE
-(int)OPR_LT
);
150 LJ_STATIC_ASSERT((int)BC_ISLE
-(int)BC_ISLT
== (int)OPR_LE
-(int)OPR_LT
);
151 LJ_STATIC_ASSERT((int)BC_ISGT
-(int)BC_ISLT
== (int)OPR_GT
-(int)OPR_LT
);
152 LJ_STATIC_ASSERT((int)BC_SUBVV
-(int)BC_ADDVV
== (int)OPR_SUB
-(int)OPR_ADD
);
153 LJ_STATIC_ASSERT((int)BC_MULVV
-(int)BC_ADDVV
== (int)OPR_MUL
-(int)OPR_ADD
);
154 LJ_STATIC_ASSERT((int)BC_DIVVV
-(int)BC_ADDVV
== (int)OPR_DIV
-(int)OPR_ADD
);
155 LJ_STATIC_ASSERT((int)BC_MODVV
-(int)BC_ADDVV
== (int)OPR_MOD
-(int)OPR_ADD
);
157 /* -- Error handling ------------------------------------------------------ */
159 LJ_NORET LJ_NOINLINE
static void err_syntax(LexState
*ls
, ErrMsg em
)
161 lj_lex_error(ls
, ls
->token
, em
);
164 LJ_NORET LJ_NOINLINE
static void err_token(LexState
*ls
, LexToken token
)
166 lj_lex_error(ls
, ls
->token
, LJ_ERR_XTOKEN
, lj_lex_token2str(ls
, token
));
169 LJ_NORET
static void err_limit(FuncState
*fs
, uint32_t limit
, const char *what
)
171 if (fs
->linedefined
== 0)
172 lj_lex_error(fs
->ls
, 0, LJ_ERR_XLIMM
, limit
, what
);
174 lj_lex_error(fs
->ls
, 0, LJ_ERR_XLIMF
, fs
->linedefined
, limit
, what
);
177 #define checklimit(fs, v, l, m) if ((v) >= (l)) err_limit(fs, l, m)
178 #define checklimitgt(fs, v, l, m) if ((v) > (l)) err_limit(fs, l, m)
179 #define checkcond(ls, c, em) { if (!(c)) err_syntax(ls, em); }
181 /* -- Management of constants --------------------------------------------- */
183 /* Return bytecode encoding for primitive constant. */
184 #define const_pri(e) check_exp((e)->k <= VKTRUE, (e)->k)
186 #define tvhaskslot(o) ((o)->u32.hi == 0)
187 #define tvkslot(o) ((o)->u32.lo)
189 /* Add a number constant. */
190 static BCReg
const_num(FuncState
*fs
, ExpDesc
*e
)
192 lua_State
*L
= fs
->L
;
194 lua_assert(expr_isnumk(e
));
195 o
= lj_tab_set(L
, fs
->kt
, &e
->u
.nval
);
202 /* Add a GC object constant. */
203 static BCReg
const_gc(FuncState
*fs
, GCobj
*gc
, uint32_t itype
)
205 lua_State
*L
= fs
->L
;
207 setgcV(L
, &key
, gc
, itype
);
208 /* NOBARRIER: the key is new or kept alive. */
209 o
= lj_tab_set(L
, fs
->kt
, &key
);
216 /* Add a string constant. */
217 static BCReg
const_str(FuncState
*fs
, ExpDesc
*e
)
219 lua_assert(expr_isstrk(e
) || e
->k
== VGLOBAL
);
220 return const_gc(fs
, obj2gco(e
->u
.sval
), LJ_TSTR
);
223 /* Anchor string constant to avoid GC. */
224 GCstr
*lj_parse_keepstr(LexState
*ls
, const char *str
, size_t len
)
226 /* NOBARRIER: the key is new or kept alive. */
227 lua_State
*L
= ls
->L
;
228 GCstr
*s
= lj_str_new(L
, str
, len
);
229 TValue
*tv
= lj_tab_setstr(L
, ls
->fs
->kt
, s
);
230 if (tvisnil(tv
)) setboolV(tv
, 1);
236 /* Anchor cdata to avoid GC. */
237 void lj_parse_keepcdata(LexState
*ls
, TValue
*tv
, GCcdata
*cd
)
239 /* NOBARRIER: the key is new or kept alive. */
240 lua_State
*L
= ls
->L
;
241 setcdataV(L
, tv
, cd
);
242 setboolV(lj_tab_set(L
, ls
->fs
->kt
, tv
), 1);
246 /* -- Jump list handling -------------------------------------------------- */
248 /* Get next element in jump list. */
249 static BCPos
jmp_next(FuncState
*fs
, BCPos pc
)
251 ptrdiff_t delta
= bc_j(fs
->bcbase
[pc
].ins
);
252 if ((BCPos
)delta
== NO_JMP
)
255 return (BCPos
)(((ptrdiff_t)pc
+1)+delta
);
258 /* Check if any of the instructions on the jump list produce no value. */
259 static int jmp_novalue(FuncState
*fs
, BCPos list
)
261 for (; list
!= NO_JMP
; list
= jmp_next(fs
, list
)) {
262 BCIns p
= fs
->bcbase
[list
>= 1 ? list
-1 : list
].ins
;
263 if (!(bc_op(p
) == BC_ISTC
|| bc_op(p
) == BC_ISFC
|| bc_a(p
) == NO_REG
))
269 /* Patch register of test instructions. */
270 static int jmp_patchtestreg(FuncState
*fs
, BCPos pc
, BCReg reg
)
272 BCIns
*ip
= &fs
->bcbase
[pc
>= 1 ? pc
-1 : pc
].ins
;
273 BCOp op
= bc_op(*ip
);
274 if (op
== BC_ISTC
|| op
== BC_ISFC
) {
275 if (reg
!= NO_REG
&& reg
!= bc_d(*ip
)) {
277 } else { /* Nothing to store or already in the right register. */
278 setbc_op(ip
, op
+(BC_IST
-BC_ISTC
));
281 } else if (bc_a(*ip
) == NO_REG
) {
283 *ip
= BCINS_AJ(BC_JMP
, bc_a(fs
->bcbase
[pc
].ins
), 0);
287 return 0; /* Cannot patch other instructions. */
292 /* Drop values for all instructions on jump list. */
293 static void jmp_dropval(FuncState
*fs
, BCPos list
)
295 for (; list
!= NO_JMP
; list
= jmp_next(fs
, list
))
296 jmp_patchtestreg(fs
, list
, NO_REG
);
299 /* Patch jump instruction to target. */
300 static void jmp_patchins(FuncState
*fs
, BCPos pc
, BCPos dest
)
302 BCIns
*jmp
= &fs
->bcbase
[pc
].ins
;
303 BCPos offset
= dest
-(pc
+1)+BCBIAS_J
;
304 lua_assert(dest
!= NO_JMP
);
305 if (offset
> BCMAX_D
)
306 err_syntax(fs
->ls
, LJ_ERR_XJUMP
);
307 setbc_d(jmp
, offset
);
310 /* Append to jump list. */
311 static void jmp_append(FuncState
*fs
, BCPos
*l1
, BCPos l2
)
315 } else if (*l1
== NO_JMP
) {
320 while ((next
= jmp_next(fs
, list
)) != NO_JMP
) /* Find last element. */
322 jmp_patchins(fs
, list
, l2
);
326 /* Patch jump list and preserve produced values. */
327 static void jmp_patchval(FuncState
*fs
, BCPos list
, BCPos vtarget
,
328 BCReg reg
, BCPos dtarget
)
330 while (list
!= NO_JMP
) {
331 BCPos next
= jmp_next(fs
, list
);
332 if (jmp_patchtestreg(fs
, list
, reg
))
333 jmp_patchins(fs
, list
, vtarget
); /* Jump to target with value. */
335 jmp_patchins(fs
, list
, dtarget
); /* Jump to default target. */
340 /* Jump to following instruction. Append to list of pending jumps. */
341 static void jmp_tohere(FuncState
*fs
, BCPos list
)
343 fs
->lasttarget
= fs
->pc
;
344 jmp_append(fs
, &fs
->jpc
, list
);
347 /* Patch jump list to target. */
348 static void jmp_patch(FuncState
*fs
, BCPos list
, BCPos target
)
350 if (target
== fs
->pc
) {
351 jmp_tohere(fs
, list
);
353 lua_assert(target
< fs
->pc
);
354 jmp_patchval(fs
, list
, target
, NO_REG
, target
);
358 /* -- Bytecode register allocator ----------------------------------------- */
360 /* Bump frame size. */
361 static void bcreg_bump(FuncState
*fs
, BCReg n
)
363 BCReg sz
= fs
->freereg
+ n
;
364 if (sz
> fs
->framesize
) {
365 if (sz
>= LJ_MAX_SLOTS
)
366 err_syntax(fs
->ls
, LJ_ERR_XSLOTS
);
367 fs
->framesize
= (uint8_t)sz
;
371 /* Reserve registers. */
372 static void bcreg_reserve(FuncState
*fs
, BCReg n
)
379 static void bcreg_free(FuncState
*fs
, BCReg reg
)
381 if (reg
>= fs
->nactvar
) {
383 lua_assert(reg
== fs
->freereg
);
387 /* Free register for expression. */
388 static void expr_free(FuncState
*fs
, ExpDesc
*e
)
390 if (e
->k
== VNONRELOC
)
391 bcreg_free(fs
, e
->u
.s
.info
);
394 /* -- Bytecode emitter ---------------------------------------------------- */
396 /* Emit bytecode instruction. */
397 static BCPos
bcemit_INS(FuncState
*fs
, BCIns ins
)
400 LexState
*ls
= fs
->ls
;
401 jmp_patchval(fs
, fs
->jpc
, pc
, NO_REG
, pc
);
403 if (LJ_UNLIKELY(pc
>= fs
->bclim
)) {
404 ptrdiff_t base
= fs
->bcbase
- ls
->bcstack
;
405 checklimit(fs
, ls
->sizebcstack
, LJ_MAX_BCINS
, "bytecode instructions");
406 lj_mem_growvec(fs
->L
, ls
->bcstack
, ls
->sizebcstack
, LJ_MAX_BCINS
,BCInsLine
);
407 fs
->bclim
= (BCPos
)(ls
->sizebcstack
- base
);
408 fs
->bcbase
= ls
->bcstack
+ base
;
410 fs
->bcbase
[pc
].ins
= ins
;
411 fs
->bcbase
[pc
].line
= ls
->lastline
;
416 #define bcemit_ABC(fs, o, a, b, c) bcemit_INS(fs, BCINS_ABC(o, a, b, c))
417 #define bcemit_AD(fs, o, a, d) bcemit_INS(fs, BCINS_AD(o, a, d))
418 #define bcemit_AJ(fs, o, a, j) bcemit_INS(fs, BCINS_AJ(o, a, j))
420 #define bcptr(fs, e) (&(fs)->bcbase[(e)->u.s.info].ins)
422 /* -- Bytecode emitter for expressions ------------------------------------ */
424 /* Discharge non-constant expression to any register. */
425 static void expr_discharge(FuncState
*fs
, ExpDesc
*e
)
428 if (e
->k
== VUPVAL
) {
429 ins
= BCINS_AD(BC_UGET
, 0, e
->u
.s
.info
);
430 } else if (e
->k
== VGLOBAL
) {
431 ins
= BCINS_AD(BC_GGET
, 0, const_str(fs
, e
));
432 } else if (e
->k
== VINDEXED
) {
433 BCReg rc
= e
->u
.s
.aux
;
434 if ((int32_t)rc
< 0) {
435 ins
= BCINS_ABC(BC_TGETS
, 0, e
->u
.s
.info
, ~rc
);
436 } else if (rc
> BCMAX_C
) {
437 ins
= BCINS_ABC(BC_TGETB
, 0, e
->u
.s
.info
, rc
-(BCMAX_C
+1));
440 ins
= BCINS_ABC(BC_TGETV
, 0, e
->u
.s
.info
, rc
);
442 bcreg_free(fs
, e
->u
.s
.info
);
443 } else if (e
->k
== VCALL
) {
444 e
->u
.s
.info
= e
->u
.s
.aux
;
447 } else if (e
->k
== VLOCAL
) {
453 e
->u
.s
.info
= bcemit_INS(fs
, ins
);
457 /* Emit bytecode to set a range of registers to nil. */
458 static void bcemit_nil(FuncState
*fs
, BCReg from
, BCReg n
)
460 if (fs
->pc
> fs
->lasttarget
) { /* No jumps to current position? */
461 BCIns
*ip
= &fs
->bcbase
[fs
->pc
-1].ins
;
462 BCReg pto
, pfrom
= bc_a(*ip
);
463 switch (bc_op(*ip
)) { /* Try to merge with the previous instruction. */
465 if (bc_d(*ip
) != ~LJ_TNIL
) break;
468 } else if (from
== pfrom
+1) {
474 fs
->pc
--; /* Drop KPRI. */
478 if (pfrom
<= from
&& from
<= pto
+1) { /* Can we connect both ranges? */
480 setbc_d(ip
, from
+n
-1); /* Patch previous instruction range. */
488 /* Emit new instruction or replace old instruction. */
489 bcemit_INS(fs
, n
== 1 ? BCINS_AD(BC_KPRI
, from
, VKNIL
) :
490 BCINS_AD(BC_KNIL
, from
, from
+n
-1));
493 /* Discharge an expression to a specific register. Ignore branches. */
494 static void expr_toreg_nobranch(FuncState
*fs
, ExpDesc
*e
, BCReg reg
)
497 expr_discharge(fs
, e
);
499 ins
= BCINS_AD(BC_KSTR
, reg
, const_str(fs
, e
));
500 } else if (e
->k
== VKNUM
) {
502 cTValue
*tv
= expr_numtv(e
);
503 if (tvisint(tv
) && checki16(intV(tv
)))
504 ins
= BCINS_AD(BC_KSHORT
, reg
, (BCReg
)(uint16_t)intV(tv
));
507 lua_Number n
= expr_numberV(e
);
508 int32_t k
= lj_num2int(n
);
509 if (checki16(k
) && n
== (lua_Number
)k
)
510 ins
= BCINS_AD(BC_KSHORT
, reg
, (BCReg
)(uint16_t)k
);
513 ins
= BCINS_AD(BC_KNUM
, reg
, const_num(fs
, e
));
515 } else if (e
->k
== VKCDATA
) {
516 fs
->flags
|= PROTO_FFI
;
517 ins
= BCINS_AD(BC_KCDATA
, reg
,
518 const_gc(fs
, obj2gco(cdataV(&e
->u
.nval
)), LJ_TCDATA
));
520 } else if (e
->k
== VRELOCABLE
) {
521 setbc_a(bcptr(fs
, e
), reg
);
523 } else if (e
->k
== VNONRELOC
) {
524 if (reg
== e
->u
.s
.info
)
526 ins
= BCINS_AD(BC_MOV
, reg
, e
->u
.s
.info
);
527 } else if (e
->k
== VKNIL
) {
528 bcemit_nil(fs
, reg
, 1);
530 } else if (e
->k
<= VKTRUE
) {
531 ins
= BCINS_AD(BC_KPRI
, reg
, const_pri(e
));
533 lua_assert(e
->k
== VVOID
|| e
->k
== VJMP
);
542 /* Forward declaration. */
543 static BCPos
bcemit_jmp(FuncState
*fs
);
545 /* Discharge an expression to a specific register. */
546 static void expr_toreg(FuncState
*fs
, ExpDesc
*e
, BCReg reg
)
548 expr_toreg_nobranch(fs
, e
, reg
);
550 jmp_append(fs
, &e
->t
, e
->u
.s
.info
); /* Add it to the true jump list. */
551 if (expr_hasjump(e
)) { /* Discharge expression with branches. */
552 BCPos jend
, jfalse
= NO_JMP
, jtrue
= NO_JMP
;
553 if (jmp_novalue(fs
, e
->t
) || jmp_novalue(fs
, e
->f
)) {
554 BCPos jval
= (e
->k
== VJMP
) ? NO_JMP
: bcemit_jmp(fs
);
555 jfalse
= bcemit_AD(fs
, BC_KPRI
, reg
, VKFALSE
);
556 bcemit_AJ(fs
, BC_JMP
, fs
->freereg
, 1);
557 jtrue
= bcemit_AD(fs
, BC_KPRI
, reg
, VKTRUE
);
558 jmp_tohere(fs
, jval
);
561 fs
->lasttarget
= jend
;
562 jmp_patchval(fs
, e
->f
, jend
, reg
, jfalse
);
563 jmp_patchval(fs
, e
->t
, jend
, reg
, jtrue
);
565 e
->f
= e
->t
= NO_JMP
;
570 /* Discharge an expression to the next free register. */
571 static void expr_tonextreg(FuncState
*fs
, ExpDesc
*e
)
573 expr_discharge(fs
, e
);
575 bcreg_reserve(fs
, 1);
576 expr_toreg(fs
, e
, fs
->freereg
- 1);
579 /* Discharge an expression to any register. */
580 static BCReg
expr_toanyreg(FuncState
*fs
, ExpDesc
*e
)
582 expr_discharge(fs
, e
);
583 if (e
->k
== VNONRELOC
) {
584 if (!expr_hasjump(e
)) return e
->u
.s
.info
; /* Already in a register. */
585 if (e
->u
.s
.info
>= fs
->nactvar
) {
586 expr_toreg(fs
, e
, e
->u
.s
.info
); /* Discharge to temp. register. */
590 expr_tonextreg(fs
, e
); /* Discharge to next register. */
594 /* Partially discharge expression to a value. */
595 static void expr_toval(FuncState
*fs
, ExpDesc
*e
)
598 expr_toanyreg(fs
, e
);
600 expr_discharge(fs
, e
);
603 /* Emit store for LHS expression. */
604 static void bcemit_store(FuncState
*fs
, ExpDesc
*var
, ExpDesc
*e
)
607 if (var
->k
== VLOCAL
) {
609 expr_toreg(fs
, e
, var
->u
.s
.info
);
611 } else if (var
->k
== VUPVAL
) {
614 ins
= BCINS_AD(BC_USETP
, var
->u
.s
.info
, const_pri(e
));
615 else if (e
->k
== VKSTR
)
616 ins
= BCINS_AD(BC_USETS
, var
->u
.s
.info
, const_str(fs
, e
));
617 else if (e
->k
== VKNUM
)
618 ins
= BCINS_AD(BC_USETN
, var
->u
.s
.info
, const_num(fs
, e
));
620 ins
= BCINS_AD(BC_USETV
, var
->u
.s
.info
, expr_toanyreg(fs
, e
));
621 } else if (var
->k
== VGLOBAL
) {
622 BCReg ra
= expr_toanyreg(fs
, e
);
623 ins
= BCINS_AD(BC_GSET
, ra
, const_str(fs
, var
));
626 lua_assert(var
->k
== VINDEXED
);
627 ra
= expr_toanyreg(fs
, e
);
629 if ((int32_t)rc
< 0) {
630 ins
= BCINS_ABC(BC_TSETS
, ra
, var
->u
.s
.info
, ~rc
);
631 } else if (rc
> BCMAX_C
) {
632 ins
= BCINS_ABC(BC_TSETB
, ra
, var
->u
.s
.info
, rc
-(BCMAX_C
+1));
634 /* Free late alloced key reg to avoid assert on free of value reg. */
635 /* This can only happen when called from expr_table(). */
636 lua_assert(e
->k
!= VNONRELOC
|| ra
< fs
->nactvar
||
637 rc
< ra
|| (bcreg_free(fs
, rc
),1));
638 ins
= BCINS_ABC(BC_TSETV
, ra
, var
->u
.s
.info
, rc
);
645 /* Emit method lookup expression. */
646 static void bcemit_method(FuncState
*fs
, ExpDesc
*e
, ExpDesc
*key
)
648 BCReg idx
, func
, obj
= expr_toanyreg(fs
, e
);
651 bcemit_AD(fs
, BC_MOV
, func
+1, obj
); /* Copy object to first argument. */
652 lua_assert(expr_isstrk(key
));
653 idx
= const_str(fs
, key
);
654 if (idx
<= BCMAX_C
) {
655 bcreg_reserve(fs
, 2);
656 bcemit_ABC(fs
, BC_TGETS
, func
, obj
, idx
);
658 bcreg_reserve(fs
, 3);
659 bcemit_AD(fs
, BC_KSTR
, func
+2, idx
);
660 bcemit_ABC(fs
, BC_TGETV
, func
, obj
, func
+2);
667 /* -- Bytecode emitter for branches --------------------------------------- */
669 /* Emit unconditional branch. */
670 static BCPos
bcemit_jmp(FuncState
*fs
)
673 BCPos j
= fs
->pc
- 1;
674 BCIns
*ip
= &fs
->bcbase
[j
].ins
;
676 if ((int32_t)j
>= (int32_t)fs
->lasttarget
&&
677 bc_op(*ip
) == BC_UCLO
)
680 j
= bcemit_AJ(fs
, BC_JMP
, fs
->freereg
, NO_JMP
);
681 jmp_append(fs
, &j
, jpc
);
685 /* Invert branch condition of bytecode instruction. */
686 static void invertcond(FuncState
*fs
, ExpDesc
*e
)
688 BCIns
*ip
= &fs
->bcbase
[e
->u
.s
.info
- 1].ins
;
689 setbc_op(ip
, bc_op(*ip
)^1);
692 /* Emit conditional branch. */
693 static BCPos
bcemit_branch(FuncState
*fs
, ExpDesc
*e
, int cond
)
696 if (e
->k
== VRELOCABLE
) {
697 BCIns
*ip
= bcptr(fs
, e
);
698 if (bc_op(*ip
) == BC_NOT
) {
699 *ip
= BCINS_AD(cond
? BC_ISF
: BC_IST
, 0, bc_d(*ip
));
700 return bcemit_jmp(fs
);
703 if (e
->k
!= VNONRELOC
) {
704 bcreg_reserve(fs
, 1);
705 expr_toreg_nobranch(fs
, e
, fs
->freereg
-1);
707 bcemit_AD(fs
, cond
? BC_ISTC
: BC_ISFC
, NO_REG
, e
->u
.s
.info
);
713 /* Emit branch on true condition. */
714 static void bcemit_branch_t(FuncState
*fs
, ExpDesc
*e
)
717 expr_discharge(fs
, e
);
718 if (e
->k
== VKSTR
|| e
->k
== VKNUM
|| e
->k
== VKTRUE
)
719 pc
= NO_JMP
; /* Never jump. */
720 else if (e
->k
== VJMP
)
721 invertcond(fs
, e
), pc
= e
->u
.s
.info
;
722 else if (e
->k
== VKFALSE
|| e
->k
== VKNIL
)
723 expr_toreg_nobranch(fs
, e
, NO_REG
), pc
= bcemit_jmp(fs
);
725 pc
= bcemit_branch(fs
, e
, 0);
726 jmp_append(fs
, &e
->f
, pc
);
727 jmp_tohere(fs
, e
->t
);
731 /* Emit branch on false condition. */
732 static void bcemit_branch_f(FuncState
*fs
, ExpDesc
*e
)
735 expr_discharge(fs
, e
);
736 if (e
->k
== VKNIL
|| e
->k
== VKFALSE
)
737 pc
= NO_JMP
; /* Never jump. */
738 else if (e
->k
== VJMP
)
740 else if (e
->k
== VKSTR
|| e
->k
== VKNUM
|| e
->k
== VKTRUE
)
741 expr_toreg_nobranch(fs
, e
, NO_REG
), pc
= bcemit_jmp(fs
);
743 pc
= bcemit_branch(fs
, e
, 1);
744 jmp_append(fs
, &e
->t
, pc
);
745 jmp_tohere(fs
, e
->f
);
749 /* -- Bytecode emitter for operators -------------------------------------- */
751 /* Try constant-folding of arithmetic operators. */
752 static int foldarith(BinOpr opr
, ExpDesc
*e1
, ExpDesc
*e2
)
756 if (!expr_isnumk_nojump(e1
) || !expr_isnumk_nojump(e2
)) return 0;
757 n
= lj_vm_foldarith(expr_numberV(e1
), expr_numberV(e2
), (int)opr
-OPR_ADD
);
759 if (tvisnan(&o
) || tvismzero(&o
)) return 0; /* Avoid NaN and -0 as consts. */
761 int32_t k
= lj_num2int(n
);
762 if ((lua_Number
)k
== n
) {
763 setintV(&e1
->u
.nval
, k
);
767 setnumV(&e1
->u
.nval
, n
);
771 /* Emit arithmetic operator. */
772 static void bcemit_arith(FuncState
*fs
, BinOpr opr
, ExpDesc
*e1
, ExpDesc
*e2
)
776 if (foldarith(opr
, e1
, e2
))
778 if (opr
== OPR_POW
) {
780 rc
= expr_toanyreg(fs
, e2
);
781 rb
= expr_toanyreg(fs
, e1
);
783 op
= opr
-OPR_ADD
+BC_ADDVV
;
784 /* Must discharge 2nd operand first since VINDEXED might free regs. */
786 if (expr_isnumk(e2
) && (rc
= const_num(fs
, e2
)) <= BCMAX_C
)
787 op
-= BC_ADDVV
-BC_ADDVN
;
789 rc
= expr_toanyreg(fs
, e2
);
790 /* 1st operand discharged by bcemit_binop_left, but need KNUM/KSHORT. */
791 lua_assert(expr_isnumk(e1
) || e1
->k
== VNONRELOC
);
793 /* Avoid two consts to satisfy bytecode constraints. */
794 if (expr_isnumk(e1
) && !expr_isnumk(e2
) &&
795 (t
= const_num(fs
, e1
)) <= BCMAX_B
) {
796 rb
= rc
; rc
= t
; op
-= BC_ADDVV
-BC_ADDNV
;
798 rb
= expr_toanyreg(fs
, e1
);
801 /* Using expr_free might cause asserts if the order is wrong. */
802 if (e1
->k
== VNONRELOC
&& e1
->u
.s
.info
>= fs
->nactvar
) fs
->freereg
--;
803 if (e2
->k
== VNONRELOC
&& e2
->u
.s
.info
>= fs
->nactvar
) fs
->freereg
--;
804 e1
->u
.s
.info
= bcemit_ABC(fs
, op
, 0, rb
, rc
);
808 /* Emit comparison operator. */
809 static void bcemit_comp(FuncState
*fs
, BinOpr opr
, ExpDesc
*e1
, ExpDesc
*e2
)
814 if (opr
== OPR_EQ
|| opr
== OPR_NE
) {
815 BCOp op
= opr
== OPR_EQ
? BC_ISEQV
: BC_ISNEV
;
817 if (expr_isk(e1
)) { e1
= e2
; e2
= eret
; } /* Need constant in 2nd arg. */
818 ra
= expr_toanyreg(fs
, e1
); /* First arg must be in a reg. */
821 case VKNIL
: case VKFALSE
: case VKTRUE
:
822 ins
= BCINS_AD(op
+(BC_ISEQP
-BC_ISEQV
), ra
, const_pri(e2
));
825 ins
= BCINS_AD(op
+(BC_ISEQS
-BC_ISEQV
), ra
, const_str(fs
, e2
));
828 ins
= BCINS_AD(op
+(BC_ISEQN
-BC_ISEQV
), ra
, const_num(fs
, e2
));
831 ins
= BCINS_AD(op
, ra
, expr_toanyreg(fs
, e2
));
835 uint32_t op
= opr
-OPR_LT
+BC_ISLT
;
837 if ((op
-BC_ISLT
) & 1) { /* GT -> LT, GE -> LE */
838 e1
= e2
; e2
= eret
; /* Swap operands. */
839 op
= ((op
-BC_ISLT
)^3)+BC_ISLT
;
841 ra
= expr_toanyreg(fs
, e1
);
842 ins
= BCINS_AD(op
, ra
, expr_toanyreg(fs
, e2
));
844 /* Using expr_free might cause asserts if the order is wrong. */
845 if (e1
->k
== VNONRELOC
&& e1
->u
.s
.info
>= fs
->nactvar
) fs
->freereg
--;
846 if (e2
->k
== VNONRELOC
&& e2
->u
.s
.info
>= fs
->nactvar
) fs
->freereg
--;
848 eret
->u
.s
.info
= bcemit_jmp(fs
);
852 /* Fixup left side of binary operator. */
853 static void bcemit_binop_left(FuncState
*fs
, BinOpr op
, ExpDesc
*e
)
856 bcemit_branch_t(fs
, e
);
857 } else if (op
== OPR_OR
) {
858 bcemit_branch_f(fs
, e
);
859 } else if (op
== OPR_CONCAT
) {
860 expr_tonextreg(fs
, e
);
861 } else if (op
== OPR_EQ
|| op
== OPR_NE
) {
862 if (!expr_isk_nojump(e
)) expr_toanyreg(fs
, e
);
864 if (!expr_isnumk_nojump(e
)) expr_toanyreg(fs
, e
);
868 /* Emit binary operator. */
869 static void bcemit_binop(FuncState
*fs
, BinOpr op
, ExpDesc
*e1
, ExpDesc
*e2
)
872 bcemit_arith(fs
, op
, e1
, e2
);
873 } else if (op
== OPR_AND
) {
874 lua_assert(e1
->t
== NO_JMP
); /* List must be closed. */
875 expr_discharge(fs
, e2
);
876 jmp_append(fs
, &e2
->f
, e1
->f
);
878 } else if (op
== OPR_OR
) {
879 lua_assert(e1
->f
== NO_JMP
); /* List must be closed. */
880 expr_discharge(fs
, e2
);
881 jmp_append(fs
, &e2
->t
, e1
->t
);
883 } else if (op
== OPR_CONCAT
) {
885 if (e2
->k
== VRELOCABLE
&& bc_op(*bcptr(fs
, e2
)) == BC_CAT
) {
886 lua_assert(e1
->u
.s
.info
== bc_b(*bcptr(fs
, e2
))-1);
888 setbc_b(bcptr(fs
, e2
), e1
->u
.s
.info
);
889 e1
->u
.s
.info
= e2
->u
.s
.info
;
891 expr_tonextreg(fs
, e2
);
894 e1
->u
.s
.info
= bcemit_ABC(fs
, BC_CAT
, 0, e1
->u
.s
.info
, e2
->u
.s
.info
);
898 lua_assert(op
== OPR_NE
|| op
== OPR_EQ
||
899 op
== OPR_LT
|| op
== OPR_GE
|| op
== OPR_LE
|| op
== OPR_GT
);
900 bcemit_comp(fs
, op
, e1
, e2
);
904 /* Emit unary operator. */
905 static void bcemit_unop(FuncState
*fs
, BCOp op
, ExpDesc
*e
)
908 /* Swap true and false lists. */
909 { BCPos temp
= e
->f
; e
->f
= e
->t
; e
->t
= temp
; }
910 jmp_dropval(fs
, e
->f
);
911 jmp_dropval(fs
, e
->t
);
912 expr_discharge(fs
, e
);
913 if (e
->k
== VKNIL
|| e
->k
== VKFALSE
) {
916 } else if (expr_isk(e
) || (LJ_HASFFI
&& e
->k
== VKCDATA
)) {
919 } else if (e
->k
== VJMP
) {
922 } else if (e
->k
== VRELOCABLE
) {
923 bcreg_reserve(fs
, 1);
924 setbc_a(bcptr(fs
, e
), fs
->freereg
-1);
925 e
->u
.s
.info
= fs
->freereg
-1;
928 lua_assert(e
->k
== VNONRELOC
);
931 lua_assert(op
== BC_UNM
|| op
== BC_LEN
);
932 if (op
== BC_UNM
&& !expr_hasjump(e
)) { /* Constant-fold negations. */
934 if (e
->k
== VKCDATA
) { /* Fold in-place since cdata is not interned. */
935 GCcdata
*cd
= cdataV(&e
->u
.nval
);
936 int64_t *p
= (int64_t *)cdataptr(cd
);
937 if (cd
->typeid == CTID_COMPLEX_DOUBLE
)
938 p
[1] ^= (int64_t)U64x(80000000,00000000);
944 if (expr_isnumk(e
) && !expr_numiszero(e
)) { /* Avoid folding to -0. */
945 TValue
*o
= expr_numtv(e
);
949 setnumV(o
, -(lua_Number
)k
);
954 o
->u64
^= U64x(80000000,00000000);
959 expr_toanyreg(fs
, e
);
962 e
->u
.s
.info
= bcemit_AD(fs
, op
, 0, e
->u
.s
.info
);
966 /* -- Lexer support ------------------------------------------------------- */
968 /* Check and consume optional token. */
969 static int lex_opt(LexState
*ls
, LexToken tok
)
971 if (ls
->token
== tok
) {
978 /* Check and consume token. */
979 static void lex_check(LexState
*ls
, LexToken tok
)
981 if (ls
->token
!= tok
)
986 /* Check for matching token. */
987 static void lex_match(LexState
*ls
, LexToken what
, LexToken who
, BCLine line
)
989 if (!lex_opt(ls
, what
)) {
990 if (line
== ls
->linenumber
) {
993 const char *swhat
= lj_lex_token2str(ls
, what
);
994 const char *swho
= lj_lex_token2str(ls
, who
);
995 lj_lex_error(ls
, ls
->token
, LJ_ERR_XMATCH
, swhat
, swho
, line
);
1000 /* Check for string token. */
1001 static GCstr
*lex_str(LexState
*ls
)
1004 if (ls
->token
!= TK_name
)
1005 err_token(ls
, TK_name
);
1006 s
= strV(&ls
->tokenval
);
1011 /* -- Variable handling --------------------------------------------------- */
1013 #define var_get(ls, fs, i) ((ls)->vstack[(fs)->varmap[(i)]])
1015 /* Define a new local variable. */
1016 static void var_new(LexState
*ls
, BCReg n
, GCstr
*name
)
1018 FuncState
*fs
= ls
->fs
;
1019 MSize vtop
= ls
->vtop
;
1020 checklimit(fs
, fs
->nactvar
+n
, LJ_MAX_LOCVAR
, "local variables");
1021 if (LJ_UNLIKELY(vtop
>= ls
->sizevstack
)) {
1022 if (ls
->sizevstack
>= LJ_MAX_VSTACK
)
1023 lj_lex_error(ls
, 0, LJ_ERR_XLIMC
, LJ_MAX_VSTACK
);
1024 lj_mem_growvec(ls
->L
, ls
->vstack
, ls
->sizevstack
, LJ_MAX_VSTACK
, VarInfo
);
1026 lua_assert((uintptr_t)name
< VARNAME__MAX
||
1027 lj_tab_getstr(fs
->kt
, name
) != NULL
);
1028 /* NOBARRIER: name is anchored in fs->kt and ls->vstack is not a GCobj. */
1029 setgcref(ls
->vstack
[vtop
].name
, obj2gco(name
));
1030 fs
->varmap
[fs
->nactvar
+n
] = (uint16_t)vtop
;
1034 #define var_new_lit(ls, n, v) \
1035 var_new(ls, (n), lj_parse_keepstr(ls, "" v, sizeof(v)-1))
1037 #define var_new_fixed(ls, n, vn) \
1038 var_new(ls, (n), (GCstr *)(uintptr_t)(vn))
1040 /* Add local variables. */
1041 static void var_add(LexState
*ls
, BCReg nvars
)
1043 FuncState
*fs
= ls
->fs
;
1044 fs
->nactvar
= (uint8_t)(fs
->nactvar
+ nvars
);
1045 for (; nvars
; nvars
--)
1046 var_get(ls
, fs
, fs
->nactvar
- nvars
).startpc
= fs
->pc
;
1049 /* Remove local variables. */
1050 static void var_remove(LexState
*ls
, BCReg tolevel
)
1052 FuncState
*fs
= ls
->fs
;
1053 while (fs
->nactvar
> tolevel
)
1054 var_get(ls
, fs
, --fs
->nactvar
).endpc
= fs
->pc
;
1057 /* Lookup local variable name. */
1058 static BCReg
var_lookup_local(FuncState
*fs
, GCstr
*n
)
1061 for (i
= fs
->nactvar
-1; i
>= 0; i
--) {
1062 if (n
== strref(var_get(fs
->ls
, fs
, i
).name
))
1065 return (BCReg
)-1; /* Not found. */
1068 /* Lookup or add upvalue index. */
1069 static MSize
var_lookup_uv(FuncState
*fs
, MSize vidx
, ExpDesc
*e
)
1071 MSize i
, n
= fs
->nuv
;
1072 for (i
= 0; i
< n
; i
++)
1073 if (fs
->uvloc
[i
].vidx
== vidx
)
1074 return i
; /* Already exists. */
1075 /* Otherwise create a new one. */
1076 checklimit(fs
, fs
->nuv
, LJ_MAX_UPVAL
, "upvalues");
1077 lua_assert(e
->k
== VLOCAL
|| e
->k
== VUPVAL
);
1078 fs
->uvloc
[n
].vidx
= (uint16_t)vidx
;
1079 fs
->uvloc
[n
].slot
= (uint16_t)(e
->u
.s
.info
| (e
->k
== VLOCAL
? 0x8000 : 0));
1084 /* Forward declaration. */
1085 static void scope_uvmark(FuncState
*fs
, BCReg level
);
1087 /* Recursively lookup variables in enclosing functions. */
1088 static MSize
var_lookup_(FuncState
*fs
, GCstr
*name
, ExpDesc
*e
, int first
)
1091 BCReg reg
= var_lookup_local(fs
, name
);
1092 if ((int32_t)reg
>= 0) { /* Local in this function? */
1093 expr_init(e
, VLOCAL
, reg
);
1095 scope_uvmark(fs
, reg
); /* Scope now has an upvalue. */
1096 return (MSize
)fs
->varmap
[reg
];
1098 MSize vidx
= var_lookup_(fs
->prev
, name
, e
, 0); /* Var in outer func? */
1099 if ((int32_t)vidx
>= 0) { /* Yes, make it an upvalue here. */
1100 e
->u
.s
.info
= (uint8_t)var_lookup_uv(fs
, vidx
, e
);
1105 } else { /* Not found in any function, must be a global. */
1106 expr_init(e
, VGLOBAL
, 0);
1109 return (MSize
)-1; /* Global. */
1112 /* Lookup variable name. */
1113 #define var_lookup(ls, e) \
1114 var_lookup_((ls)->fs, lex_str(ls), (e), 1)
1116 /* -- Function state management ------------------------------------------- */
1118 /* Fixup bytecode for prototype. */
1119 static void fs_fixup_bc(FuncState
*fs
, GCproto
*pt
, BCIns
*bc
, MSize n
)
1121 BCInsLine
*base
= fs
->bcbase
;
1124 bc
[0] = BCINS_AD((fs
->flags
& PROTO_VARARG
) ? BC_FUNCV
: BC_FUNCF
,
1126 for (i
= 1; i
< n
; i
++)
1127 bc
[i
] = base
[i
].ins
;
1130 /* Fixup constants for prototype. */
1131 static void fs_fixup_k(FuncState
*fs
, GCproto
*pt
, void *kptr
)
1137 checklimitgt(fs
, fs
->nkn
, BCMAX_D
+1, "constants");
1138 checklimitgt(fs
, fs
->nkgc
, BCMAX_D
+1, "constants");
1139 setmref(pt
->k
, kptr
);
1140 pt
->sizekn
= fs
->nkn
;
1141 pt
->sizekgc
= fs
->nkgc
;
1143 array
= tvref(kt
->array
);
1144 for (i
= 0; i
< kt
->asize
; i
++)
1145 if (tvhaskslot(&array
[i
])) {
1146 TValue
*tv
= &((TValue
*)kptr
)[tvkslot(&array
[i
])];
1148 setintV(tv
, (int32_t)i
);
1150 setnumV(tv
, (lua_Number
)i
);
1152 node
= noderef(kt
->node
);
1154 for (i
= 0; i
<= hmask
; i
++) {
1156 if (tvhaskslot(&n
->val
)) {
1157 ptrdiff_t kidx
= (ptrdiff_t)tvkslot(&n
->val
);
1158 lua_assert(!tvisint(&n
->key
));
1159 if (tvisnum(&n
->key
)) {
1160 TValue
*tv
= &((TValue
*)kptr
)[kidx
];
1162 lua_Number nn
= numV(&n
->key
);
1163 int32_t k
= lj_num2int(nn
);
1164 lua_assert(!tvismzero(&n
->key
));
1165 if ((lua_Number
)k
== nn
)
1173 GCobj
*o
= gcV(&n
->key
);
1174 setgcref(((GCRef
*)kptr
)[~kidx
], o
);
1175 lj_gc_objbarrier(fs
->L
, pt
, o
);
1181 /* Fixup upvalues for prototype. */
1182 static void fs_fixup_uv(FuncState
*fs
, GCproto
*pt
, uint16_t *uv
)
1184 MSize i
, n
= fs
->nuv
;
1185 setmref(pt
->uv
, uv
);
1187 for (i
= 0; i
< n
; i
++)
1188 uv
[i
] = fs
->uvloc
[i
].slot
;
1191 #ifndef LUAJIT_DISABLE_DEBUGINFO
1192 /* Prepare lineinfo for prototype. */
1193 static size_t fs_prep_line(FuncState
*fs
, BCLine numline
)
1195 return (fs
->pc
-1) << (numline
< 256 ? 0 : numline
< 65536 ? 1 : 2);
1198 /* Fixup lineinfo for prototype. */
1199 static void fs_fixup_line(FuncState
*fs
, GCproto
*pt
,
1200 void *lineinfo
, BCLine numline
)
1202 BCInsLine
*base
= fs
->bcbase
+ 1;
1203 BCLine first
= fs
->linedefined
;
1204 MSize i
= 0, n
= fs
->pc
-1;
1205 pt
->firstline
= fs
->linedefined
;
1206 pt
->numline
= numline
;
1207 setmref(pt
->lineinfo
, lineinfo
);
1208 if (LJ_LIKELY(numline
< 256)) {
1209 uint8_t *li
= (uint8_t *)lineinfo
;
1211 BCLine delta
= base
[i
].line
- first
;
1212 lua_assert(delta
>= 0 && delta
< 256);
1213 li
[i
] = (uint8_t)delta
;
1215 } else if (LJ_LIKELY(numline
< 65536)) {
1216 uint16_t *li
= (uint16_t *)lineinfo
;
1218 BCLine delta
= base
[i
].line
- first
;
1219 lua_assert(delta
>= 0 && delta
< 65536);
1220 li
[i
] = (uint16_t)delta
;
1223 uint32_t *li
= (uint32_t *)lineinfo
;
1225 BCLine delta
= base
[i
].line
- first
;
1226 lua_assert(delta
>= 0);
1227 li
[i
] = (uint32_t)delta
;
1232 /* Resize buffer if needed. */
1233 static LJ_NOINLINE
void fs_buf_resize(LexState
*ls
, MSize len
)
1235 MSize sz
= ls
->sb
.sz
* 2;
1236 while (ls
->sb
.n
+ len
> sz
) sz
= sz
* 2;
1237 lj_str_resizebuf(ls
->L
, &ls
->sb
, sz
);
1240 static LJ_AINLINE
void fs_buf_need(LexState
*ls
, MSize len
)
1242 if (LJ_UNLIKELY(ls
->sb
.n
+ len
> ls
->sb
.sz
))
1243 fs_buf_resize(ls
, len
);
1246 /* Add string to buffer. */
1247 static void fs_buf_str(LexState
*ls
, const char *str
, MSize len
)
1249 char *p
= ls
->sb
.buf
+ ls
->sb
.n
;
1252 for (i
= 0; i
< len
; i
++) p
[i
] = str
[i
];
1255 /* Add ULEB128 value to buffer. */
1256 static void fs_buf_uleb128(LexState
*ls
, uint32_t v
)
1259 uint8_t *p
= (uint8_t *)ls
->sb
.buf
;
1260 for (; v
>= 0x80; v
>>= 7)
1261 p
[n
++] = (uint8_t)((v
& 0x7f) | 0x80);
1262 p
[n
++] = (uint8_t)v
;
1266 /* Prepare variable info for prototype. */
1267 static size_t fs_prep_var(LexState
*ls
, FuncState
*fs
, size_t *ofsvar
)
1269 VarInfo
*vstack
= fs
->ls
->vstack
;
1272 lj_str_resetbuf(&ls
->sb
); /* Copy to temp. string buffer. */
1273 /* Store upvalue names. */
1274 for (i
= 0, n
= fs
->nuv
; i
< n
; i
++) {
1275 GCstr
*s
= strref(vstack
[fs
->uvloc
[i
].vidx
].name
);
1276 MSize len
= s
->len
+1;
1277 fs_buf_need(ls
, len
);
1278 fs_buf_str(ls
, strdata(s
), len
);
1281 vstack
+= fs
->vbase
;
1283 /* Store local variable names and compressed ranges. */
1284 for (i
= 0, n
= ls
->vtop
- fs
->vbase
; i
< n
; i
++) {
1285 GCstr
*s
= strref(vstack
[i
].name
);
1286 BCPos startpc
= vstack
[i
].startpc
, endpc
= vstack
[i
].endpc
;
1287 if ((uintptr_t)s
< VARNAME__MAX
) {
1288 fs_buf_need(ls
, 1 + 2*5);
1289 ls
->sb
.buf
[ls
->sb
.n
++] = (uint8_t)(uintptr_t)s
;
1291 MSize len
= s
->len
+1;
1292 fs_buf_need(ls
, len
+ 2*5);
1293 fs_buf_str(ls
, strdata(s
), len
);
1295 fs_buf_uleb128(ls
, startpc
-lastpc
);
1296 fs_buf_uleb128(ls
, endpc
-startpc
);
1300 ls
->sb
.buf
[ls
->sb
.n
++] = '\0'; /* Terminator for varinfo. */
1304 /* Fixup variable info for prototype. */
1305 static void fs_fixup_var(LexState
*ls
, GCproto
*pt
, uint8_t *p
, size_t ofsvar
)
1307 setmref(pt
->uvinfo
, p
);
1308 setmref(pt
->varinfo
, (char *)p
+ ofsvar
);
1309 memcpy(p
, ls
->sb
.buf
, ls
->sb
.n
); /* Copy from temp. string buffer. */
1313 /* Initialize with empty debug info, if disabled. */
1314 #define fs_prep_line(fs, numline) (UNUSED(numline), 0)
1315 #define fs_fixup_line(fs, pt, li, numline) \
1316 pt->firstline = pt->numline = 0, setmref((pt)->lineinfo, NULL)
1317 #define fs_prep_var(ls, fs, ofsvar) (UNUSED(ofsvar), 0)
1318 #define fs_fixup_var(ls, pt, p, ofsvar) \
1319 setmref((pt)->uvinfo, NULL), setmref((pt)->varinfo, NULL)
1323 /* Check if bytecode op returns. */
1324 static int bcopisret(BCOp op
)
1327 case BC_CALLMT
: case BC_CALLT
:
1328 case BC_RETM
: case BC_RET
: case BC_RET0
: case BC_RET1
:
1335 /* Fixup return instruction for prototype. */
1336 static void fs_fixup_ret(FuncState
*fs
)
1338 BCPos lastpc
= fs
->pc
;
1339 if (lastpc
<= fs
->lasttarget
|| !bcopisret(bc_op(fs
->bcbase
[lastpc
-1].ins
))) {
1340 if (fs
->flags
& PROTO_CHILD
)
1341 bcemit_AJ(fs
, BC_UCLO
, 0, 0);
1342 bcemit_AD(fs
, BC_RET0
, 0, 1); /* Need final return. */
1344 /* May need to fixup returns encoded before first function was created. */
1345 if (fs
->flags
& PROTO_FIXUP_RETURN
) {
1347 for (pc
= 0; pc
< lastpc
; pc
++) {
1348 BCIns ins
= fs
->bcbase
[pc
].ins
;
1350 switch (bc_op(ins
)) {
1351 case BC_CALLMT
: case BC_CALLT
:
1352 case BC_RETM
: case BC_RET
: case BC_RET0
: case BC_RET1
:
1353 offset
= bcemit_INS(fs
, ins
)-(pc
+1)+BCBIAS_J
; /* Copy return ins. */
1354 if (offset
> BCMAX_D
)
1355 err_syntax(fs
->ls
, LJ_ERR_XFIXUP
);
1356 /* Replace with UCLO plus branch. */
1357 fs
->bcbase
[pc
].ins
= BCINS_AD(BC_UCLO
, 0, offset
);
1360 return; /* We're done. */
1368 /* Finish a FuncState and return the new prototype. */
1369 static GCproto
*fs_finish(LexState
*ls
, BCLine line
)
1371 lua_State
*L
= ls
->L
;
1372 FuncState
*fs
= ls
->fs
;
1373 BCLine numline
= line
- fs
->linedefined
;
1374 size_t sizept
, ofsk
, ofsuv
, ofsli
, ofsdbg
, ofsvar
;
1377 /* Apply final fixups. */
1378 lua_assert(fs
->bl
== NULL
);
1382 /* Calculate total size of prototype including all colocated arrays. */
1383 sizept
= sizeof(GCproto
) + fs
->pc
*sizeof(BCIns
) + fs
->nkgc
*sizeof(GCRef
);
1384 sizept
= (sizept
+ sizeof(TValue
)-1) & ~(sizeof(TValue
)-1);
1385 ofsk
= sizept
; sizept
+= fs
->nkn
*sizeof(TValue
);
1386 ofsuv
= sizept
; sizept
+= ((fs
->nuv
+1)&~1)*2;
1387 ofsli
= sizept
; sizept
+= fs_prep_line(fs
, numline
);
1388 ofsdbg
= sizept
; sizept
+= fs_prep_var(ls
, fs
, &ofsvar
);
1390 /* Allocate prototype and initialize its fields. */
1391 pt
= (GCproto
*)lj_mem_newgco(L
, (MSize
)sizept
);
1392 pt
->gct
= ~LJ_TPROTO
;
1393 pt
->sizept
= (MSize
)sizept
;
1395 pt
->flags
= fs
->flags
;
1396 pt
->numparams
= fs
->numparams
;
1397 pt
->framesize
= fs
->framesize
;
1398 setgcref(pt
->chunkname
, obj2gco(ls
->chunkname
));
1400 /* Close potentially uninitialized gap between bc and kgc. */
1401 *(uint32_t *)((char *)pt
+ ofsk
- sizeof(GCRef
)*(fs
->nkgc
+1)) = 0;
1402 fs_fixup_bc(fs
, pt
, (BCIns
*)((char *)pt
+ sizeof(GCproto
)), fs
->pc
);
1403 fs_fixup_k(fs
, pt
, (void *)((char *)pt
+ ofsk
));
1404 fs_fixup_uv(fs
, pt
, (uint16_t *)((char *)pt
+ ofsuv
));
1405 fs_fixup_line(fs
, pt
, (void *)((char *)pt
+ ofsli
), numline
);
1406 fs_fixup_var(ls
, pt
, (uint8_t *)((char *)pt
+ ofsdbg
), ofsvar
);
1408 lj_vmevent_send(L
, BC
,
1409 setprotoV(L
, L
->top
++, pt
);
1412 L
->top
--; /* Pop table of constants. */
1413 ls
->vtop
= fs
->vbase
; /* Reset variable stack. */
1415 lua_assert(ls
->fs
!= NULL
|| ls
->token
== TK_eof
);
1419 /* Initialize a new FuncState. */
1420 static void fs_init(LexState
*ls
, FuncState
*fs
)
1422 lua_State
*L
= ls
->L
;
1423 fs
->prev
= ls
->fs
; ls
->fs
= fs
; /* Append to list. */
1425 fs
->vbase
= ls
->vtop
;
1437 fs
->framesize
= 1; /* Minimum frame size. */
1438 fs
->kt
= lj_tab_new(L
, 0, 0);
1439 /* Anchor table of constants in stack to avoid being collected. */
1440 settabV(L
, L
->top
, fs
->kt
);
1444 /* -- Expressions --------------------------------------------------------- */
1446 /* Forward declaration. */
1447 static void expr(LexState
*ls
, ExpDesc
*v
);
1449 /* Return string expression. */
1450 static void expr_str(LexState
*ls
, ExpDesc
*e
)
1452 expr_init(e
, VKSTR
, 0);
1453 e
->u
.sval
= lex_str(ls
);
1456 /* Return index expression. */
1457 static void expr_index(FuncState
*fs
, ExpDesc
*t
, ExpDesc
*e
)
1459 /* Already called: expr_toval(fs, e). */
1461 if (expr_isnumk(e
)) {
1463 if (tvisint(expr_numtv(e
))) {
1464 int32_t k
= intV(expr_numtv(e
));
1466 t
->u
.s
.aux
= BCMAX_C
+1+(uint32_t)k
; /* 256..511: const byte key */
1471 lua_Number n
= expr_numberV(e
);
1472 int32_t k
= lj_num2int(n
);
1473 if (checku8(k
) && n
== (lua_Number
)k
) {
1474 t
->u
.s
.aux
= BCMAX_C
+1+(uint32_t)k
; /* 256..511: const byte key */
1478 } else if (expr_isstrk(e
)) {
1479 BCReg idx
= const_str(fs
, e
);
1480 if (idx
<= BCMAX_C
) {
1481 t
->u
.s
.aux
= ~idx
; /* -256..-1: const string key */
1485 t
->u
.s
.aux
= expr_toanyreg(fs
, e
); /* 0..255: register */
1488 /* Parse index expression with named field. */
1489 static void expr_field(LexState
*ls
, ExpDesc
*v
)
1491 FuncState
*fs
= ls
->fs
;
1493 expr_toanyreg(fs
, v
);
1494 lj_lex_next(ls
); /* Skip dot or colon. */
1496 expr_index(fs
, v
, &key
);
1499 /* Parse index expression with brackets. */
1500 static void expr_bracket(LexState
*ls
, ExpDesc
*v
)
1502 lj_lex_next(ls
); /* Skip '['. */
1504 expr_toval(ls
->fs
, v
);
1508 /* Get value of constant expression. */
1509 static void expr_kvalue(TValue
*v
, ExpDesc
*e
)
1511 if (e
->k
<= VKTRUE
) {
1512 setitype(v
, ~(uint32_t)e
->k
);
1513 } else if (e
->k
== VKSTR
) {
1514 setgcref(v
->gcr
, obj2gco(e
->u
.sval
));
1515 setitype(v
, LJ_TSTR
);
1517 lua_assert(tvisnumber(expr_numtv(e
)));
1518 *v
= *expr_numtv(e
);
1522 /* Parse table constructor expression. */
1523 static void expr_table(LexState
*ls
, ExpDesc
*e
)
1525 FuncState
*fs
= ls
->fs
;
1526 BCLine line
= ls
->linenumber
;
1528 int vcall
= 0, needarr
= 0;
1529 int32_t narr
= 1; /* First array index. */
1530 uint32_t nhash
= 0; /* Number of hash entries. */
1531 BCReg freg
= fs
->freereg
;
1532 BCPos pc
= bcemit_AD(fs
, BC_TNEW
, freg
, 0);
1533 expr_init(e
, VNONRELOC
, freg
);
1534 bcreg_reserve(fs
, 1);
1537 while (ls
->token
!= '}') {
1540 if (ls
->token
== '[') {
1541 expr_bracket(ls
, &key
); /* Already calls expr_toval. */
1542 if (!expr_isk(&key
)) expr_index(fs
, e
, &key
);
1543 if (expr_isnumk(&key
) && expr_numiszero(&key
)) needarr
= 1; else nhash
++;
1545 } else if (ls
->token
== TK_name
&& lj_lex_lookahead(ls
) == '=') {
1550 expr_init(&key
, VKNUM
, 0);
1551 setintV(&key
.u
.nval
, narr
);
1553 needarr
= vcall
= 1;
1556 if (expr_isk_nojump(&val
) && expr_isk(&key
) && key
.k
!= VKNIL
) {
1558 if (!t
) { /* Create template table on demand. */
1560 t
= lj_tab_new(fs
->L
, 0, 0);
1561 kidx
= const_gc(fs
, obj2gco(t
), LJ_TTAB
);
1562 fs
->bcbase
[pc
].ins
= BCINS_AD(BC_TDUP
, freg
-1, kidx
);
1565 expr_kvalue(&k
, &key
);
1566 expr_kvalue(lj_tab_set(fs
->L
, t
, &k
), &val
);
1567 lj_gc_anybarriert(fs
->L
, t
);
1569 if (val
.k
!= VCALL
) { expr_toanyreg(fs
, &val
); vcall
= 0; }
1570 if (expr_isk(&key
)) expr_index(fs
, e
, &key
);
1571 bcemit_store(fs
, e
, &val
);
1574 if (!lex_opt(ls
, ',') && !lex_opt(ls
, ';')) break;
1576 lex_match(ls
, '}', '{', line
);
1578 BCInsLine
*ilp
= &fs
->bcbase
[fs
->pc
-1];
1580 lua_assert(bc_a(ilp
->ins
) == freg
&&
1581 bc_op(ilp
->ins
) == (narr
> 256 ? BC_TSETV
: BC_TSETB
));
1582 expr_init(&en
, VKNUM
, 0);
1583 en
.u
.nval
.u32
.lo
= narr
-1;
1584 en
.u
.nval
.u32
.hi
= 0x43300000; /* Biased integer to avoid denormals. */
1585 if (narr
> 256) { fs
->pc
--; ilp
--; }
1586 ilp
->ins
= BCINS_AD(BC_TSETM
, freg
, const_num(fs
, &en
));
1587 setbc_b(&ilp
[-1].ins
, 0);
1589 if (pc
== fs
->pc
-1) { /* Make expr relocable if possible. */
1594 e
->k
= VNONRELOC
; /* May have been changed by expr_index. */
1596 if (!t
) { /* Construct TNEW RD: hhhhhaaaaaaaaaaa. */
1597 BCIns
*ip
= &fs
->bcbase
[pc
].ins
;
1598 if (!needarr
) narr
= 0;
1599 else if (narr
< 3) narr
= 3;
1600 else if (narr
> 0x7ff) narr
= 0x7ff;
1601 setbc_d(ip
, (uint32_t)narr
|(hsize2hbits(nhash
)<<11));
1605 /* Parse function parameters. */
1606 static BCReg
parse_params(LexState
*ls
, int needself
)
1608 FuncState
*fs
= ls
->fs
;
1612 var_new_lit(ls
, nparams
++, "self");
1613 if (ls
->token
!= ')') {
1615 if (ls
->token
== TK_name
) {
1616 var_new(ls
, nparams
++, lex_str(ls
));
1617 } else if (ls
->token
== TK_dots
) {
1619 fs
->flags
|= PROTO_VARARG
;
1622 err_syntax(ls
, LJ_ERR_XPARAM
);
1624 } while (lex_opt(ls
, ','));
1626 var_add(ls
, nparams
);
1627 lua_assert(fs
->nactvar
== nparams
);
1628 bcreg_reserve(fs
, nparams
);
1633 /* Forward declaration. */
1634 static void parse_chunk(LexState
*ls
);
1636 /* Parse body of a function. */
1637 static void parse_body(LexState
*ls
, ExpDesc
*e
, int needself
, BCLine line
)
1639 FuncState fs
, *pfs
= ls
->fs
;
1641 ptrdiff_t oldbase
= pfs
->bcbase
- ls
->bcstack
;
1643 fs
.linedefined
= line
;
1644 fs
.numparams
= (uint8_t)parse_params(ls
, needself
);
1645 fs
.bcbase
= pfs
->bcbase
+ pfs
->pc
;
1646 fs
.bclim
= pfs
->bclim
- pfs
->pc
;
1647 bcemit_AD(&fs
, BC_FUNCF
, 0, 0); /* Placeholder. */
1649 if (ls
->token
!= TK_end
) lex_match(ls
, TK_end
, TK_function
, line
);
1650 pt
= fs_finish(ls
, (ls
->lastline
= ls
->linenumber
));
1651 pfs
->bcbase
= ls
->bcstack
+ oldbase
; /* May have been reallocated. */
1652 pfs
->bclim
= (BCPos
)(ls
->sizebcstack
- oldbase
);
1653 /* Store new prototype in the constant array of the parent. */
1654 expr_init(e
, VRELOCABLE
,
1655 bcemit_AD(pfs
, BC_FNEW
, 0, const_gc(pfs
, obj2gco(pt
), LJ_TPROTO
)));
1657 pfs
->flags
|= (fs
.flags
& PROTO_FFI
);
1659 if (!(pfs
->flags
& PROTO_CHILD
)) {
1660 if (pfs
->flags
& PROTO_HAS_RETURN
)
1661 pfs
->flags
|= PROTO_FIXUP_RETURN
;
1662 pfs
->flags
|= PROTO_CHILD
;
1667 /* Parse expression list. Last expression is left open. */
1668 static BCReg
expr_list(LexState
*ls
, ExpDesc
*v
)
1672 while (lex_opt(ls
, ',')) {
1673 expr_tonextreg(ls
->fs
, v
);
1680 /* Parse function argument list. */
1681 static void parse_args(LexState
*ls
, ExpDesc
*e
)
1683 FuncState
*fs
= ls
->fs
;
1687 BCLine line
= ls
->linenumber
;
1688 if (ls
->token
== '(') {
1689 if (line
!= ls
->lastline
)
1690 err_syntax(ls
, LJ_ERR_XAMBIG
);
1692 if (ls
->token
== ')') { /* f(). */
1695 expr_list(ls
, &args
);
1696 if (args
.k
== VCALL
) /* f(a, b, g()) or f(a, b, ...). */
1697 setbc_b(bcptr(fs
, &args
), 0); /* Pass on multiple results. */
1699 lex_match(ls
, ')', '(', line
);
1700 } else if (ls
->token
== '{') {
1701 expr_table(ls
, &args
);
1702 } else if (ls
->token
== TK_string
) {
1703 expr_init(&args
, VKSTR
, 0);
1704 args
.u
.sval
= strV(&ls
->tokenval
);
1707 err_syntax(ls
, LJ_ERR_XFUNARG
);
1708 return; /* Silence compiler. */
1710 lua_assert(e
->k
== VNONRELOC
);
1711 base
= e
->u
.s
.info
; /* Base register for call. */
1712 if (args
.k
== VCALL
) {
1713 ins
= BCINS_ABC(BC_CALLM
, base
, 2, args
.u
.s
.aux
- base
- 1);
1715 if (args
.k
!= VVOID
)
1716 expr_tonextreg(fs
, &args
);
1717 ins
= BCINS_ABC(BC_CALL
, base
, 2, fs
->freereg
- base
);
1719 expr_init(e
, VCALL
, bcemit_INS(fs
, ins
));
1721 fs
->bcbase
[fs
->pc
- 1].line
= line
;
1722 fs
->freereg
= base
+1; /* Leave one result by default. */
1725 /* Parse primary expression. */
1726 static void expr_primary(LexState
*ls
, ExpDesc
*v
)
1728 FuncState
*fs
= ls
->fs
;
1729 /* Parse prefix expression. */
1730 if (ls
->token
== '(') {
1731 BCLine line
= ls
->linenumber
;
1734 lex_match(ls
, ')', '(', line
);
1735 expr_discharge(ls
->fs
, v
);
1736 } else if (ls
->token
== TK_name
) {
1739 err_syntax(ls
, LJ_ERR_XSYMBOL
);
1741 for (;;) { /* Parse multiple expression suffixes. */
1742 if (ls
->token
== '.') {
1744 } else if (ls
->token
== '[') {
1746 expr_toanyreg(fs
, v
);
1747 expr_bracket(ls
, &key
);
1748 expr_index(fs
, v
, &key
);
1749 } else if (ls
->token
== ':') {
1753 bcemit_method(fs
, v
, &key
);
1755 } else if (ls
->token
== '(' || ls
->token
== TK_string
|| ls
->token
== '{') {
1756 expr_tonextreg(fs
, v
);
1764 /* Parse simple expression. */
1765 static void expr_simple(LexState
*ls
, ExpDesc
*v
)
1767 switch (ls
->token
) {
1769 expr_init(v
, (LJ_HASFFI
&& tviscdata(&ls
->tokenval
)) ? VKCDATA
: VKNUM
, 0);
1770 copyTV(ls
->L
, &v
->u
.nval
, &ls
->tokenval
);
1773 expr_init(v
, VKSTR
, 0);
1774 v
->u
.sval
= strV(&ls
->tokenval
);
1777 expr_init(v
, VKNIL
, 0);
1780 expr_init(v
, VKTRUE
, 0);
1783 expr_init(v
, VKFALSE
, 0);
1785 case TK_dots
: { /* Vararg. */
1786 FuncState
*fs
= ls
->fs
;
1788 checkcond(ls
, fs
->flags
& PROTO_VARARG
, LJ_ERR_XDOTS
);
1789 bcreg_reserve(fs
, 1);
1790 base
= fs
->freereg
-1;
1791 expr_init(v
, VCALL
, bcemit_ABC(fs
, BC_VARG
, base
, 2, fs
->numparams
));
1795 case '{': /* Table constructor. */
1800 parse_body(ls
, v
, 0, ls
->linenumber
);
1803 expr_primary(ls
, v
);
1809 /* Manage syntactic levels to avoid blowing up the stack. */
1810 static void synlevel_begin(LexState
*ls
)
1812 if (++ls
->level
>= LJ_MAX_XLEVEL
)
1813 lj_lex_error(ls
, 0, LJ_ERR_XLEVELS
);
1816 #define synlevel_end(ls) ((ls)->level--)
1818 /* Convert token to binary operator. */
1819 static BinOpr
token2binop(LexToken tok
)
1822 case '+': return OPR_ADD
;
1823 case '-': return OPR_SUB
;
1824 case '*': return OPR_MUL
;
1825 case '/': return OPR_DIV
;
1826 case '%': return OPR_MOD
;
1827 case '^': return OPR_POW
;
1828 case TK_concat
: return OPR_CONCAT
;
1829 case TK_ne
: return OPR_NE
;
1830 case TK_eq
: return OPR_EQ
;
1831 case '<': return OPR_LT
;
1832 case TK_le
: return OPR_LE
;
1833 case '>': return OPR_GT
;
1834 case TK_ge
: return OPR_GE
;
1835 case TK_and
: return OPR_AND
;
1836 case TK_or
: return OPR_OR
;
1837 default: return OPR_NOBINOPR
;
1841 /* Priorities for each binary operator. ORDER OPR. */
1842 static const struct {
1843 uint8_t left
; /* Left priority. */
1844 uint8_t right
; /* Right priority. */
1846 {6,6}, {6,6}, {7,7}, {7,7}, {7,7}, /* ADD SUB MUL DIV MOD */
1847 {10,9}, {5,4}, /* POW CONCAT (right associative) */
1848 {3,3}, {3,3}, /* EQ NE */
1849 {3,3}, {3,3}, {3,3}, {3,3}, /* LT GE GT LE */
1850 {2,2}, {1,1} /* AND OR */
1853 #define UNARY_PRIORITY 8 /* Priority for unary operators. */
1855 /* Forward declaration. */
1856 static BinOpr
expr_binop(LexState
*ls
, ExpDesc
*v
, uint32_t limit
);
1858 /* Parse unary expression. */
1859 static void expr_unop(LexState
*ls
, ExpDesc
*v
)
1862 if (ls
->token
== TK_not
) {
1864 } else if (ls
->token
== '-') {
1866 } else if (ls
->token
== '#') {
1873 expr_binop(ls
, v
, UNARY_PRIORITY
);
1874 bcemit_unop(ls
->fs
, op
, v
);
1877 /* Parse binary expressions with priority higher than the limit. */
1878 static BinOpr
expr_binop(LexState
*ls
, ExpDesc
*v
, uint32_t limit
)
1883 op
= token2binop(ls
->token
);
1884 while (op
!= OPR_NOBINOPR
&& priority
[op
].left
> limit
) {
1888 bcemit_binop_left(ls
->fs
, op
, v
);
1889 /* Parse binary expression with higher priority. */
1890 nextop
= expr_binop(ls
, &v2
, priority
[op
].right
);
1891 bcemit_binop(ls
->fs
, op
, v
, &v2
);
1895 return op
; /* Return unconsumed binary operator (if any). */
1898 /* Parse expression. */
1899 static void expr(LexState
*ls
, ExpDesc
*v
)
1901 expr_binop(ls
, v
, 0); /* Priority 0: parse whole expression. */
1904 /* Assign expression to the next register. */
1905 static void expr_next(LexState
*ls
)
1909 expr_tonextreg(ls
->fs
, &e
);
1912 /* Parse conditional expression. */
1913 static BCPos
expr_cond(LexState
*ls
)
1917 if (v
.k
== VKNIL
) v
.k
= VKFALSE
;
1918 bcemit_branch_t(ls
->fs
, &v
);
1922 /* -- Scope handling ------------------------------------------------------ */
1924 /* Begin a scope. */
1925 static void scope_begin(FuncState
*fs
, FuncScope
*bl
, int isbreakable
)
1927 bl
->breaklist
= NO_JMP
;
1928 bl
->isbreakable
= (uint8_t)isbreakable
;
1929 bl
->nactvar
= (uint8_t)fs
->nactvar
;
1933 lua_assert(fs
->freereg
== fs
->nactvar
);
1937 static void scope_end(FuncState
*fs
)
1939 FuncScope
*bl
= fs
->bl
;
1941 var_remove(fs
->ls
, bl
->nactvar
);
1942 fs
->freereg
= fs
->nactvar
;
1943 lua_assert(bl
->nactvar
== fs
->nactvar
);
1944 /* A scope is either breakable or has upvalues. */
1945 lua_assert(!bl
->isbreakable
|| !bl
->upval
);
1947 bcemit_AJ(fs
, BC_UCLO
, bl
->nactvar
, 0);
1948 else /* Avoid in upval case, it clears lasttarget and kills UCLO+JMP join. */
1949 jmp_tohere(fs
, bl
->breaklist
);
1952 /* Mark scope as having an upvalue. */
1953 static void scope_uvmark(FuncState
*fs
, BCReg level
)
1956 for (bl
= fs
->bl
; bl
&& bl
->nactvar
> level
; bl
= bl
->prev
)
1962 /* Parse 'break' statement. */
1963 static void parse_break(LexState
*ls
)
1965 FuncState
*fs
= ls
->fs
;
1969 for (bl
= fs
->bl
; bl
&& !bl
->isbreakable
; bl
= bl
->prev
)
1970 upval
|= bl
->upval
; /* Collect upvalues in intervening scopes. */
1971 if (!bl
) /* Error if no breakable scope found. */
1972 err_syntax(ls
, LJ_ERR_XBREAK
);
1973 savefr
= fs
->freereg
;
1974 fs
->freereg
= bl
->nactvar
; /* Shrink slots to help data-flow analysis. */
1976 bcemit_AJ(fs
, BC_UCLO
, bl
->nactvar
, 0); /* Close upvalues. */
1977 jmp_append(fs
, &bl
->breaklist
, bcemit_jmp(fs
));
1978 fs
->freereg
= savefr
;
1981 /* Check for end of block. */
1982 static int endofblock(LexToken token
)
1985 case TK_else
: case TK_elseif
: case TK_end
: case TK_until
: case TK_eof
:
1992 /* Parse 'return' statement. */
1993 static void parse_return(LexState
*ls
)
1996 FuncState
*fs
= ls
->fs
;
1997 lj_lex_next(ls
); /* Skip 'return'. */
1998 fs
->flags
|= PROTO_HAS_RETURN
;
1999 if (endofblock(ls
->token
) || ls
->token
== ';') { /* Bare return. */
2000 ins
= BCINS_AD(BC_RET0
, 0, 1);
2001 } else { /* Return with one or more values. */
2002 ExpDesc e
; /* Receives the _last_ expression in the list. */
2003 BCReg nret
= expr_list(ls
, &e
);
2004 if (nret
== 1) { /* Return one result. */
2005 if (e
.k
== VCALL
) { /* Check for tail call. */
2006 BCIns
*ip
= bcptr(fs
, &e
);
2007 /* It doesn't pay off to add BC_VARGT just for 'return ...'. */
2008 if (bc_op(*ip
) == BC_VARG
) goto notailcall
;
2010 ins
= BCINS_AD(bc_op(*ip
)-BC_CALL
+BC_CALLT
, bc_a(*ip
), bc_c(*ip
));
2011 } else { /* Can return the result from any register. */
2012 ins
= BCINS_AD(BC_RET1
, expr_toanyreg(fs
, &e
), 2);
2015 if (e
.k
== VCALL
) { /* Append all results from a call. */
2017 setbc_b(bcptr(fs
, &e
), 0);
2018 ins
= BCINS_AD(BC_RETM
, fs
->nactvar
, e
.u
.s
.aux
- fs
->nactvar
);
2020 expr_tonextreg(fs
, &e
); /* Force contiguous registers. */
2021 ins
= BCINS_AD(BC_RET
, fs
->nactvar
, nret
+1);
2025 if (fs
->flags
& PROTO_CHILD
)
2026 bcemit_AJ(fs
, BC_UCLO
, 0, 0); /* May need to close upvalues first. */
2027 bcemit_INS(fs
, ins
);
2030 /* Parse a block. */
2031 static void parse_block(LexState
*ls
)
2033 FuncState
*fs
= ls
->fs
;
2035 scope_begin(fs
, &bl
, 0);
2037 lua_assert(bl
.breaklist
== NO_JMP
);
2041 /* -- Assignments --------------------------------------------------------- */
2043 /* List of LHS variables. */
2044 typedef struct LHSVarList
{
2045 ExpDesc v
; /* LHS variable. */
2046 struct LHSVarList
*prev
; /* Link to previous LHS variable. */
2049 /* Eliminate write-after-read hazards for local variable assignment. */
2050 static void assign_hazard(LexState
*ls
, LHSVarList
*lh
, const ExpDesc
*v
)
2052 FuncState
*fs
= ls
->fs
;
2053 BCReg reg
= v
->u
.s
.info
; /* Check against this variable. */
2054 BCReg tmp
= fs
->freereg
; /* Rename to this temp. register (if needed). */
2056 for (; lh
; lh
= lh
->prev
) {
2057 if (lh
->v
.k
== VINDEXED
) {
2058 if (lh
->v
.u
.s
.info
== reg
) { /* t[i], t = 1, 2 */
2060 lh
->v
.u
.s
.info
= tmp
;
2062 if (lh
->v
.u
.s
.aux
== reg
) { /* t[i], i = 1, 2 */
2064 lh
->v
.u
.s
.aux
= tmp
;
2069 bcemit_AD(fs
, BC_MOV
, tmp
, reg
); /* Rename conflicting variable. */
2070 bcreg_reserve(fs
, 1);
2074 /* Adjust LHS/RHS of an assignment. */
2075 static void assign_adjust(LexState
*ls
, BCReg nvars
, BCReg nexps
, ExpDesc
*e
)
2077 FuncState
*fs
= ls
->fs
;
2078 int32_t extra
= (int32_t)nvars
- (int32_t)nexps
;
2079 if (e
->k
== VCALL
) {
2080 extra
++; /* Compensate for the VCALL itself. */
2081 if (extra
< 0) extra
= 0;
2082 setbc_b(bcptr(fs
, e
), extra
+1); /* Fixup call results. */
2083 if (extra
> 1) bcreg_reserve(fs
, (BCReg
)extra
-1);
2086 expr_tonextreg(fs
, e
); /* Close last expression. */
2087 if (extra
> 0) { /* Leftover LHS are set to nil. */
2088 BCReg reg
= fs
->freereg
;
2089 bcreg_reserve(fs
, (BCReg
)extra
);
2090 bcemit_nil(fs
, reg
, (BCReg
)extra
);
2095 /* Recursively parse assignment statement. */
2096 static void parse_assignment(LexState
*ls
, LHSVarList
*lh
, BCReg nvars
)
2099 checkcond(ls
, VLOCAL
<= lh
->v
.k
&& lh
->v
.k
<= VINDEXED
, LJ_ERR_XSYNTAX
);
2100 if (lex_opt(ls
, ',')) { /* Collect LHS list and recurse upwards. */
2103 expr_primary(ls
, &vl
.v
);
2104 if (vl
.v
.k
== VLOCAL
)
2105 assign_hazard(ls
, lh
, &vl
.v
);
2106 checklimit(ls
->fs
, ls
->level
+ nvars
, LJ_MAX_XLEVEL
, "variable names");
2107 parse_assignment(ls
, &vl
, nvars
+1);
2108 } else { /* Parse RHS. */
2111 nexps
= expr_list(ls
, &e
);
2112 if (nexps
== nvars
) {
2114 if (bc_op(*bcptr(ls
->fs
, &e
)) == BC_VARG
) { /* Vararg assignment. */
2117 } else { /* Multiple call results. */
2118 e
.u
.s
.info
= e
.u
.s
.aux
; /* Base of call is not relocatable. */
2122 bcemit_store(ls
->fs
, &lh
->v
, &e
);
2125 assign_adjust(ls
, nvars
, nexps
, &e
);
2127 ls
->fs
->freereg
-= nexps
- nvars
; /* Drop leftover regs. */
2129 /* Assign RHS to LHS and recurse downwards. */
2130 expr_init(&e
, VNONRELOC
, ls
->fs
->freereg
-1);
2131 bcemit_store(ls
->fs
, &lh
->v
, &e
);
2134 /* Parse call statement or assignment. */
2135 static void parse_call_assign(LexState
*ls
)
2137 FuncState
*fs
= ls
->fs
;
2139 expr_primary(ls
, &vl
.v
);
2140 if (vl
.v
.k
== VCALL
) { /* Function call statement. */
2141 setbc_b(bcptr(fs
, &vl
.v
), 1); /* No results. */
2142 } else { /* Start of an assignment. */
2144 parse_assignment(ls
, &vl
, 1);
2148 /* Parse 'local' statement. */
2149 static void parse_local(LexState
*ls
)
2151 if (lex_opt(ls
, TK_function
)) { /* Local function declaration. */
2153 FuncState
*fs
= ls
->fs
;
2154 var_new(ls
, 0, lex_str(ls
));
2155 expr_init(&v
, VLOCAL
, fs
->freereg
);
2156 bcreg_reserve(fs
, 1);
2158 parse_body(ls
, &b
, 0, ls
->linenumber
);
2159 bcemit_store(fs
, &v
, &b
);
2160 /* The upvalue is in scope, but the local is only valid after the store. */
2161 var_get(ls
, fs
, fs
->nactvar
- 1).startpc
= fs
->pc
;
2162 } else { /* Local variable declaration. */
2164 BCReg nexps
, nvars
= 0;
2165 do { /* Collect LHS. */
2166 var_new(ls
, nvars
++, lex_str(ls
));
2167 } while (lex_opt(ls
, ','));
2168 if (lex_opt(ls
, '=')) { /* Optional RHS. */
2169 nexps
= expr_list(ls
, &e
);
2170 } else { /* Or implicitly set to nil. */
2174 assign_adjust(ls
, nvars
, nexps
, &e
);
2179 /* Parse 'function' statement. */
2180 static void parse_func(LexState
*ls
, BCLine line
)
2185 lj_lex_next(ls
); /* Skip 'function'. */
2186 /* Parse function name. */
2188 while (ls
->token
== '.') /* Multiple dot-separated fields. */
2190 if (ls
->token
== ':') { /* Optional colon to signify method call. */
2194 parse_body(ls
, &b
, needself
, line
);
2196 bcemit_store(fs
, &v
, &b
);
2197 fs
->bcbase
[fs
->pc
- 1].line
= line
; /* Set line for the store. */
2200 /* -- Loop and conditional statements ------------------------------------- */
2202 /* Parse 'while' statement. */
2203 static void parse_while(LexState
*ls
, BCLine line
)
2205 FuncState
*fs
= ls
->fs
;
2206 BCPos start
, loop
, condexit
;
2208 lj_lex_next(ls
); /* Skip 'while'. */
2209 start
= fs
->lasttarget
= fs
->pc
;
2210 condexit
= expr_cond(ls
);
2211 scope_begin(fs
, &bl
, 1);
2212 lex_check(ls
, TK_do
);
2213 loop
= bcemit_AD(fs
, BC_LOOP
, fs
->nactvar
, 0);
2215 jmp_patch(fs
, bcemit_jmp(fs
), start
);
2216 lex_match(ls
, TK_end
, TK_while
, line
);
2218 jmp_tohere(fs
, condexit
);
2219 jmp_patchins(fs
, loop
, fs
->pc
);
2222 /* Parse 'repeat' statement. */
2223 static void parse_repeat(LexState
*ls
, BCLine line
)
2225 FuncState
*fs
= ls
->fs
;
2226 BCPos loop
= fs
->lasttarget
= fs
->pc
;
2229 scope_begin(fs
, &bl1
, 1); /* Breakable loop scope. */
2230 scope_begin(fs
, &bl2
, 0); /* Inner scope. */
2231 lj_lex_next(ls
); /* Skip 'repeat'. */
2232 bcemit_AD(fs
, BC_LOOP
, fs
->nactvar
, 0);
2234 lex_match(ls
, TK_until
, TK_repeat
, line
);
2235 condexit
= expr_cond(ls
); /* Parse condition (still inside inner scope). */
2236 if (!bl2
.upval
) { /* No upvalues? Just end inner scope. */
2238 } else { /* Otherwise generate: cond: UCLO+JMP out, !cond: UCLO+JMP loop. */
2239 parse_break(ls
); /* Break from loop and close upvalues. */
2240 jmp_tohere(fs
, condexit
);
2241 scope_end(fs
); /* End inner scope and close upvalues. */
2242 condexit
= bcemit_jmp(fs
);
2244 jmp_patch(fs
, condexit
, loop
); /* Jump backwards if !cond. */
2245 jmp_patchins(fs
, loop
, fs
->pc
);
2246 scope_end(fs
); /* End loop scope. */
2249 /* Parse numeric 'for'. */
2250 static void parse_for_num(LexState
*ls
, GCstr
*varname
, BCLine line
)
2252 FuncState
*fs
= ls
->fs
;
2253 BCReg base
= fs
->freereg
;
2255 BCPos loop
, loopend
;
2256 /* Hidden control variables. */
2257 var_new_fixed(ls
, FORL_IDX
, VARNAME_FOR_IDX
);
2258 var_new_fixed(ls
, FORL_STOP
, VARNAME_FOR_STOP
);
2259 var_new_fixed(ls
, FORL_STEP
, VARNAME_FOR_STEP
);
2260 /* Visible copy of index variable. */
2261 var_new(ls
, FORL_EXT
, varname
);
2266 if (lex_opt(ls
, ',')) {
2269 bcemit_AD(fs
, BC_KSHORT
, fs
->freereg
, 1); /* Default step is 1. */
2270 bcreg_reserve(fs
, 1);
2272 var_add(ls
, 3); /* Hidden control variables. */
2273 lex_check(ls
, TK_do
);
2274 loop
= bcemit_AJ(fs
, BC_FORI
, base
, NO_JMP
);
2275 scope_begin(fs
, &bl
, 0); /* Scope for visible variables. */
2277 bcreg_reserve(fs
, 1);
2280 /* Perform loop inversion. Loop control instructions are at the end. */
2281 loopend
= bcemit_AJ(fs
, BC_FORL
, base
, NO_JMP
);
2282 fs
->bcbase
[loopend
].line
= line
; /* Fix line for control ins. */
2283 jmp_patchins(fs
, loopend
, loop
+1);
2284 jmp_patchins(fs
, loop
, fs
->pc
);
2287 /* Try to predict whether the iterator is next() and specialize the bytecode.
2288 ** Detecting next() and pairs() by name is simplistic, but quite effective.
2289 ** The interpreter backs off if the check for the closure fails at runtime.
2291 static int predict_next(LexState
*ls
, FuncState
*fs
, BCPos pc
)
2293 BCIns ins
= fs
->bcbase
[pc
].ins
;
2296 switch (bc_op(ins
)) {
2298 name
= gco2str(gcref(var_get(ls
, fs
, bc_d(ins
)).name
));
2301 name
= gco2str(gcref(ls
->vstack
[fs
->uvloc
[bc_d(ins
)].vidx
].name
));
2304 /* There's no inverse index (yet), so lookup the strings. */
2305 o
= lj_tab_getstr(fs
->kt
, lj_str_newlit(ls
->L
, "pairs"));
2306 if (o
&& tvhaskslot(o
) && tvkslot(o
) == bc_d(ins
))
2308 o
= lj_tab_getstr(fs
->kt
, lj_str_newlit(ls
->L
, "next"));
2309 if (o
&& tvhaskslot(o
) && tvkslot(o
) == bc_d(ins
))
2315 return (name
->len
== 5 && !strcmp(strdata(name
), "pairs")) ||
2316 (name
->len
== 4 && !strcmp(strdata(name
), "next"));
2319 /* Parse 'for' iterator. */
2320 static void parse_for_iter(LexState
*ls
, GCstr
*indexname
)
2322 FuncState
*fs
= ls
->fs
;
2326 BCReg base
= fs
->freereg
+ 3;
2327 BCPos loop
, loopend
, exprpc
= fs
->pc
;
2330 /* Hidden control variables. */
2331 var_new_fixed(ls
, nvars
++, VARNAME_FOR_GEN
);
2332 var_new_fixed(ls
, nvars
++, VARNAME_FOR_STATE
);
2333 var_new_fixed(ls
, nvars
++, VARNAME_FOR_CTL
);
2334 /* Visible variables returned from iterator. */
2335 var_new(ls
, nvars
++, indexname
);
2336 while (lex_opt(ls
, ','))
2337 var_new(ls
, nvars
++, lex_str(ls
));
2338 lex_check(ls
, TK_in
);
2339 line
= ls
->linenumber
;
2340 assign_adjust(ls
, 3, expr_list(ls
, &e
), &e
);
2341 bcreg_bump(fs
, 3); /* The iterator needs another 3 slots (func + 2 args). */
2342 isnext
= (nvars
<= 5 && predict_next(ls
, fs
, exprpc
));
2343 var_add(ls
, 3); /* Hidden control variables. */
2344 lex_check(ls
, TK_do
);
2345 loop
= bcemit_AJ(fs
, isnext
? BC_ISNEXT
: BC_JMP
, base
, NO_JMP
);
2346 scope_begin(fs
, &bl
, 0); /* Scope for visible variables. */
2347 var_add(ls
, nvars
-3);
2348 bcreg_reserve(fs
, nvars
-3);
2351 /* Perform loop inversion. Loop control instructions are at the end. */
2352 jmp_patchins(fs
, loop
, fs
->pc
);
2353 bcemit_ABC(fs
, isnext
? BC_ITERN
: BC_ITERC
, base
, nvars
-3+1, 2+1);
2354 loopend
= bcemit_AJ(fs
, BC_ITERL
, base
, NO_JMP
);
2355 fs
->bcbase
[loopend
-1].line
= line
; /* Fix line for control ins. */
2356 fs
->bcbase
[loopend
].line
= line
;
2357 jmp_patchins(fs
, loopend
, loop
+1);
2360 /* Parse 'for' statement. */
2361 static void parse_for(LexState
*ls
, BCLine line
)
2363 FuncState
*fs
= ls
->fs
;
2366 scope_begin(fs
, &bl
, 1); /* Breakable loop scope. */
2367 lj_lex_next(ls
); /* Skip 'for'. */
2368 varname
= lex_str(ls
); /* Get first variable name. */
2369 if (ls
->token
== '=')
2370 parse_for_num(ls
, varname
, line
);
2371 else if (ls
->token
== ',' || ls
->token
== TK_in
)
2372 parse_for_iter(ls
, varname
);
2374 err_syntax(ls
, LJ_ERR_XFOR
);
2375 lex_match(ls
, TK_end
, TK_for
, line
);
2376 scope_end(fs
); /* Resolve break list. */
2379 /* Parse condition and 'then' block. */
2380 static BCPos
parse_then(LexState
*ls
)
2383 lj_lex_next(ls
); /* Skip 'if' or 'elseif'. */
2384 condexit
= expr_cond(ls
);
2385 lex_check(ls
, TK_then
);
2390 /* Parse 'if' statement. */
2391 static void parse_if(LexState
*ls
, BCLine line
)
2393 FuncState
*fs
= ls
->fs
;
2395 BCPos escapelist
= NO_JMP
;
2396 flist
= parse_then(ls
);
2397 while (ls
->token
== TK_elseif
) { /* Parse multiple 'elseif' blocks. */
2398 jmp_append(fs
, &escapelist
, bcemit_jmp(fs
));
2399 jmp_tohere(fs
, flist
);
2400 flist
= parse_then(ls
);
2402 if (ls
->token
== TK_else
) { /* Parse optional 'else' block. */
2403 jmp_append(fs
, &escapelist
, bcemit_jmp(fs
));
2404 jmp_tohere(fs
, flist
);
2405 lj_lex_next(ls
); /* Skip 'else'. */
2408 jmp_append(fs
, &escapelist
, flist
);
2410 jmp_tohere(fs
, escapelist
);
2411 lex_match(ls
, TK_end
, TK_if
, line
);
2414 /* -- Parse statements ---------------------------------------------------- */
2416 /* Parse a statement. Returns 1 if it must be the last one in a chunk. */
2417 static int parse_stmt(LexState
*ls
)
2419 BCLine line
= ls
->linenumber
;
2420 switch (ls
->token
) {
2425 parse_while(ls
, line
);
2430 lex_match(ls
, TK_end
, TK_do
, line
);
2433 parse_for(ls
, line
);
2436 parse_repeat(ls
, line
);
2439 parse_func(ls
, line
);
2447 return 1; /* Must be last. */
2451 return 1; /* Must be last. */
2452 #ifdef LUAJIT_ENABLE_LUA52COMPAT
2458 parse_call_assign(ls
);
2464 /* A chunk is a list of statements optionally separated by semicolons. */
2465 static void parse_chunk(LexState
*ls
)
2469 while (!islast
&& !endofblock(ls
->token
)) {
2470 islast
= parse_stmt(ls
);
2472 lua_assert(ls
->fs
->framesize
>= ls
->fs
->freereg
&&
2473 ls
->fs
->freereg
>= ls
->fs
->nactvar
);
2474 ls
->fs
->freereg
= ls
->fs
->nactvar
; /* Free registers after each stmt. */
2479 /* Entry point of bytecode parser. */
2480 GCproto
*lj_parse(LexState
*ls
)
2484 lua_State
*L
= ls
->L
;
2485 #ifdef LUAJIT_DISABLE_DEBUGINFO
2486 ls
->chunkname
= lj_str_newlit(L
, "=");
2488 ls
->chunkname
= lj_str_newz(L
, ls
->chunkarg
);
2490 setstrV(L
, L
->top
, ls
->chunkname
); /* Anchor chunkname string. */
2498 fs
.flags
|= PROTO_VARARG
; /* Main chunk is always a vararg func. */
2499 bcemit_AD(&fs
, BC_FUNCV
, 0, 0); /* Placeholder. */
2500 lj_lex_next(ls
); /* Read-ahead first token. */
2502 if (ls
->token
!= TK_eof
)
2503 err_token(ls
, TK_eof
);
2504 pt
= fs_finish(ls
, ls
->linenumber
);
2505 L
->top
--; /* Drop chunkname. */
2506 lua_assert(fs
.prev
== NULL
);
2507 lua_assert(ls
->fs
== NULL
);
2508 lua_assert(pt
->sizeuv
== 0);