diff options
| author | Andy Belle-Isle <drumsetmonkey@gmail.com> | 2019-08-30 00:45:36 -0400 |
|---|---|---|
| committer | Andy Belle-Isle <drumsetmonkey@gmail.com> | 2019-08-30 00:45:36 -0400 |
| commit | dc2493e7525bb7633f697ef10f72b72b46222249 (patch) | |
| tree | 9816755219e65d3f47fdce81c78f3736a7ddb8ab /deps/LuaJIT/src/lj_parse.c | |
| parent | 9d2b31797d0cfd130802b69261df2cd402e39b49 (diff) | |
Forget what I said, I just need to change git attributes to mark for vendor
Diffstat (limited to 'deps/LuaJIT/src/lj_parse.c')
| -rw-r--r-- | deps/LuaJIT/src/lj_parse.c | 2728 |
1 files changed, 0 insertions, 2728 deletions
diff --git a/deps/LuaJIT/src/lj_parse.c b/deps/LuaJIT/src/lj_parse.c deleted file mode 100644 index c8efafa..0000000 --- a/deps/LuaJIT/src/lj_parse.c +++ /dev/null @@ -1,2728 +0,0 @@ -/* -** Lua parser (source code -> bytecode). -** Copyright (C) 2005-2017 Mike Pall. See Copyright Notice in luajit.h -** -** Major portions taken verbatim or adapted from the Lua interpreter. -** Copyright (C) 1994-2008 Lua.org, PUC-Rio. See Copyright Notice in lua.h -*/ - -#define lj_parse_c -#define LUA_CORE - -#include "lj_obj.h" -#include "lj_gc.h" -#include "lj_err.h" -#include "lj_debug.h" -#include "lj_buf.h" -#include "lj_str.h" -#include "lj_tab.h" -#include "lj_func.h" -#include "lj_state.h" -#include "lj_bc.h" -#if LJ_HASFFI -#include "lj_ctype.h" -#endif -#include "lj_strfmt.h" -#include "lj_lex.h" -#include "lj_parse.h" -#include "lj_vm.h" -#include "lj_vmevent.h" - -/* -- Parser structures and definitions ----------------------------------- */ - -/* Expression kinds. */ -typedef enum { - /* Constant expressions must be first and in this order: */ - VKNIL, - VKFALSE, - VKTRUE, - VKSTR, /* sval = string value */ - VKNUM, /* nval = number value */ - VKLAST = VKNUM, - VKCDATA, /* nval = cdata value, not treated as a constant expression */ - /* Non-constant expressions follow: */ - VLOCAL, /* info = local register, aux = vstack index */ - VUPVAL, /* info = upvalue index, aux = vstack index */ - VGLOBAL, /* sval = string value */ - VINDEXED, /* info = table register, aux = index reg/byte/string const */ - VJMP, /* info = instruction PC */ - VRELOCABLE, /* info = instruction PC */ - VNONRELOC, /* info = result register */ - VCALL, /* info = instruction PC, aux = base */ - VVOID -} ExpKind; - -/* Expression descriptor. */ -typedef struct ExpDesc { - union { - struct { - uint32_t info; /* Primary info. */ - uint32_t aux; /* Secondary info. */ - } s; - TValue nval; /* Number value. */ - GCstr *sval; /* String value. */ - } u; - ExpKind k; - BCPos t; /* True condition jump list. */ - BCPos f; /* False condition jump list. */ -} ExpDesc; - -/* Macros for expressions. */ -#define expr_hasjump(e) ((e)->t != (e)->f) - -#define expr_isk(e) ((e)->k <= VKLAST) -#define expr_isk_nojump(e) (expr_isk(e) && !expr_hasjump(e)) -#define expr_isnumk(e) ((e)->k == VKNUM) -#define expr_isnumk_nojump(e) (expr_isnumk(e) && !expr_hasjump(e)) -#define expr_isstrk(e) ((e)->k == VKSTR) - -#define expr_numtv(e) check_exp(expr_isnumk((e)), &(e)->u.nval) -#define expr_numberV(e) numberVnum(expr_numtv((e))) - -/* Initialize expression. */ -static LJ_AINLINE void expr_init(ExpDesc *e, ExpKind k, uint32_t info) -{ - e->k = k; - e->u.s.info = info; - e->f = e->t = NO_JMP; -} - -/* Check number constant for +-0. */ -static int expr_numiszero(ExpDesc *e) -{ - TValue *o = expr_numtv(e); - return tvisint(o) ? (intV(o) == 0) : tviszero(o); -} - -/* Per-function linked list of scope blocks. */ -typedef struct FuncScope { - struct FuncScope *prev; /* Link to outer scope. */ - MSize vstart; /* Start of block-local variables. */ - uint8_t nactvar; /* Number of active vars outside the scope. */ - uint8_t flags; /* Scope flags. */ -} FuncScope; - -#define FSCOPE_LOOP 0x01 /* Scope is a (breakable) loop. */ -#define FSCOPE_BREAK 0x02 /* Break used in scope. */ -#define FSCOPE_GOLA 0x04 /* Goto or label used in scope. */ -#define FSCOPE_UPVAL 0x08 /* Upvalue in scope. */ -#define FSCOPE_NOCLOSE 0x10 /* Do not close upvalues. */ - -#define NAME_BREAK ((GCstr *)(uintptr_t)1) - -/* Index into variable stack. */ -typedef uint16_t VarIndex; -#define LJ_MAX_VSTACK (65536 - LJ_MAX_UPVAL) - -/* Variable/goto/label info. */ -#define VSTACK_VAR_RW 0x01 /* R/W variable. */ -#define VSTACK_GOTO 0x02 /* Pending goto. */ -#define VSTACK_LABEL 0x04 /* Label. */ - -/* Per-function state. */ -typedef struct FuncState { - GCtab *kt; /* Hash table for constants. */ - LexState *ls; /* Lexer state. */ - lua_State *L; /* Lua state. */ - FuncScope *bl; /* Current scope. */ - struct FuncState *prev; /* Enclosing function. */ - BCPos pc; /* Next bytecode position. */ - BCPos lasttarget; /* Bytecode position of last jump target. */ - BCPos jpc; /* Pending jump list to next bytecode. */ - BCReg freereg; /* First free register. */ - BCReg nactvar; /* Number of active local variables. */ - BCReg nkn, nkgc; /* Number of lua_Number/GCobj constants */ - BCLine linedefined; /* First line of the function definition. */ - BCInsLine *bcbase; /* Base of bytecode stack. */ - BCPos bclim; /* Limit of bytecode stack. */ - MSize vbase; /* Base of variable stack for this function. */ - uint8_t flags; /* Prototype flags. */ - uint8_t numparams; /* Number of parameters. */ - uint8_t framesize; /* Fixed frame size. */ - uint8_t nuv; /* Number of upvalues */ - VarIndex varmap[LJ_MAX_LOCVAR]; /* Map from register to variable idx. */ - VarIndex uvmap[LJ_MAX_UPVAL]; /* Map from upvalue to variable idx. */ - VarIndex uvtmp[LJ_MAX_UPVAL]; /* Temporary upvalue map. */ -} FuncState; - -/* Binary and unary operators. ORDER OPR */ -typedef enum BinOpr { - OPR_ADD, OPR_SUB, OPR_MUL, OPR_DIV, OPR_MOD, OPR_POW, /* ORDER ARITH */ - OPR_CONCAT, - OPR_NE, OPR_EQ, - OPR_LT, OPR_GE, OPR_LE, OPR_GT, - OPR_AND, OPR_OR, - OPR_NOBINOPR -} BinOpr; - -LJ_STATIC_ASSERT((int)BC_ISGE-(int)BC_ISLT == (int)OPR_GE-(int)OPR_LT); -LJ_STATIC_ASSERT((int)BC_ISLE-(int)BC_ISLT == (int)OPR_LE-(int)OPR_LT); -LJ_STATIC_ASSERT((int)BC_ISGT-(int)BC_ISLT == (int)OPR_GT-(int)OPR_LT); -LJ_STATIC_ASSERT((int)BC_SUBVV-(int)BC_ADDVV == (int)OPR_SUB-(int)OPR_ADD); -LJ_STATIC_ASSERT((int)BC_MULVV-(int)BC_ADDVV == (int)OPR_MUL-(int)OPR_ADD); -LJ_STATIC_ASSERT((int)BC_DIVVV-(int)BC_ADDVV == (int)OPR_DIV-(int)OPR_ADD); -LJ_STATIC_ASSERT((int)BC_MODVV-(int)BC_ADDVV == (int)OPR_MOD-(int)OPR_ADD); - -/* -- Error handling ------------------------------------------------------ */ - -LJ_NORET LJ_NOINLINE static void err_syntax(LexState *ls, ErrMsg em) -{ - lj_lex_error(ls, ls->tok, em); -} - -LJ_NORET LJ_NOINLINE static void err_token(LexState *ls, LexToken tok) -{ - lj_lex_error(ls, ls->tok, LJ_ERR_XTOKEN, lj_lex_token2str(ls, tok)); -} - -LJ_NORET static void err_limit(FuncState *fs, uint32_t limit, const char *what) -{ - if (fs->linedefined == 0) - lj_lex_error(fs->ls, 0, LJ_ERR_XLIMM, limit, what); - else - lj_lex_error(fs->ls, 0, LJ_ERR_XLIMF, fs->linedefined, limit, what); -} - -#define checklimit(fs, v, l, m) if ((v) >= (l)) err_limit(fs, l, m) -#define checklimitgt(fs, v, l, m) if ((v) > (l)) err_limit(fs, l, m) -#define checkcond(ls, c, em) { if (!(c)) err_syntax(ls, em); } - -/* -- Management of constants --------------------------------------------- */ - -/* Return bytecode encoding for primitive constant. */ -#define const_pri(e) check_exp((e)->k <= VKTRUE, (e)->k) - -#define tvhaskslot(o) ((o)->u32.hi == 0) -#define tvkslot(o) ((o)->u32.lo) - -/* Add a number constant. */ -static BCReg const_num(FuncState *fs, ExpDesc *e) -{ - lua_State *L = fs->L; - TValue *o; - lua_assert(expr_isnumk(e)); - o = lj_tab_set(L, fs->kt, &e->u.nval); - if (tvhaskslot(o)) - return tvkslot(o); - o->u64 = fs->nkn; - return fs->nkn++; -} - -/* Add a GC object constant. */ -static BCReg const_gc(FuncState *fs, GCobj *gc, uint32_t itype) -{ - lua_State *L = fs->L; - TValue key, *o; - setgcV(L, &key, gc, itype); - /* NOBARRIER: the key is new or kept alive. */ - o = lj_tab_set(L, fs->kt, &key); - if (tvhaskslot(o)) - return tvkslot(o); - o->u64 = fs->nkgc; - return fs->nkgc++; -} - -/* Add a string constant. */ -static BCReg const_str(FuncState *fs, ExpDesc *e) -{ - lua_assert(expr_isstrk(e) || e->k == VGLOBAL); - return const_gc(fs, obj2gco(e->u.sval), LJ_TSTR); -} - -/* Anchor string constant to avoid GC. */ -GCstr *lj_parse_keepstr(LexState *ls, const char *str, size_t len) -{ - /* NOBARRIER: the key is new or kept alive. */ - lua_State *L = ls->L; - GCstr *s = lj_str_new(L, str, len); - TValue *tv = lj_tab_setstr(L, ls->fs->kt, s); - if (tvisnil(tv)) setboolV(tv, 1); - lj_gc_check(L); - return s; -} - -#if LJ_HASFFI -/* Anchor cdata to avoid GC. */ -void lj_parse_keepcdata(LexState *ls, TValue *tv, GCcdata *cd) -{ - /* NOBARRIER: the key is new or kept alive. */ - lua_State *L = ls->L; - setcdataV(L, tv, cd); - setboolV(lj_tab_set(L, ls->fs->kt, tv), 1); -} -#endif - -/* -- Jump list handling -------------------------------------------------- */ - -/* Get next element in jump list. */ -static BCPos jmp_next(FuncState *fs, BCPos pc) -{ - ptrdiff_t delta = bc_j(fs->bcbase[pc].ins); - if ((BCPos)delta == NO_JMP) - return NO_JMP; - else - return (BCPos)(((ptrdiff_t)pc+1)+delta); -} - -/* Check if any of the instructions on the jump list produce no value. */ -static int jmp_novalue(FuncState *fs, BCPos list) -{ - for (; list != NO_JMP; list = jmp_next(fs, list)) { - BCIns p = fs->bcbase[list >= 1 ? list-1 : list].ins; - if (!(bc_op(p) == BC_ISTC || bc_op(p) == BC_ISFC || bc_a(p) == NO_REG)) - return 1; - } - return 0; -} - -/* Patch register of test instructions. */ -static int jmp_patchtestreg(FuncState *fs, BCPos pc, BCReg reg) -{ - BCInsLine *ilp = &fs->bcbase[pc >= 1 ? pc-1 : pc]; - BCOp op = bc_op(ilp->ins); - if (op == BC_ISTC || op == BC_ISFC) { - if (reg != NO_REG && reg != bc_d(ilp->ins)) { - setbc_a(&ilp->ins, reg); - } else { /* Nothing to store or already in the right register. */ - setbc_op(&ilp->ins, op+(BC_IST-BC_ISTC)); - setbc_a(&ilp->ins, 0); - } - } else if (bc_a(ilp->ins) == NO_REG) { - if (reg == NO_REG) { - ilp->ins = BCINS_AJ(BC_JMP, bc_a(fs->bcbase[pc].ins), 0); - } else { - setbc_a(&ilp->ins, reg); - if (reg >= bc_a(ilp[1].ins)) - setbc_a(&ilp[1].ins, reg+1); - } - } else { - return 0; /* Cannot patch other instructions. */ - } - return 1; -} - -/* Drop values for all instructions on jump list. */ -static void jmp_dropval(FuncState *fs, BCPos list) -{ - for (; list != NO_JMP; list = jmp_next(fs, list)) - jmp_patchtestreg(fs, list, NO_REG); -} - -/* Patch jump instruction to target. */ -static void jmp_patchins(FuncState *fs, BCPos pc, BCPos dest) -{ - BCIns *jmp = &fs->bcbase[pc].ins; - BCPos offset = dest-(pc+1)+BCBIAS_J; - lua_assert(dest != NO_JMP); - if (offset > BCMAX_D) - err_syntax(fs->ls, LJ_ERR_XJUMP); - setbc_d(jmp, offset); -} - -/* Append to jump list. */ -static void jmp_append(FuncState *fs, BCPos *l1, BCPos l2) -{ - if (l2 == NO_JMP) { - return; - } else if (*l1 == NO_JMP) { - *l1 = l2; - } else { - BCPos list = *l1; - BCPos next; - while ((next = jmp_next(fs, list)) != NO_JMP) /* Find last element. */ - list = next; - jmp_patchins(fs, list, l2); - } -} - -/* Patch jump list and preserve produced values. */ -static void jmp_patchval(FuncState *fs, BCPos list, BCPos vtarget, - BCReg reg, BCPos dtarget) -{ - while (list != NO_JMP) { - BCPos next = jmp_next(fs, list); - if (jmp_patchtestreg(fs, list, reg)) - jmp_patchins(fs, list, vtarget); /* Jump to target with value. */ - else - jmp_patchins(fs, list, dtarget); /* Jump to default target. */ - list = next; - } -} - -/* Jump to following instruction. Append to list of pending jumps. */ -static void jmp_tohere(FuncState *fs, BCPos list) -{ - fs->lasttarget = fs->pc; - jmp_append(fs, &fs->jpc, list); -} - -/* Patch jump list to target. */ -static void jmp_patch(FuncState *fs, BCPos list, BCPos target) -{ - if (target == fs->pc) { - jmp_tohere(fs, list); - } else { - lua_assert(target < fs->pc); - jmp_patchval(fs, list, target, NO_REG, target); - } -} - -/* -- Bytecode register allocator ----------------------------------------- */ - -/* Bump frame size. */ -static void bcreg_bump(FuncState *fs, BCReg n) -{ - BCReg sz = fs->freereg + n; - if (sz > fs->framesize) { - if (sz >= LJ_MAX_SLOTS) - err_syntax(fs->ls, LJ_ERR_XSLOTS); - fs->framesize = (uint8_t)sz; - } -} - -/* Reserve registers. */ -static void bcreg_reserve(FuncState *fs, BCReg n) -{ - bcreg_bump(fs, n); - fs->freereg += n; -} - -/* Free register. */ -static void bcreg_free(FuncState *fs, BCReg reg) -{ - if (reg >= fs->nactvar) { - fs->freereg--; - lua_assert(reg == fs->freereg); - } -} - -/* Free register for expression. */ -static void expr_free(FuncState *fs, ExpDesc *e) -{ - if (e->k == VNONRELOC) - bcreg_free(fs, e->u.s.info); -} - -/* -- Bytecode emitter ---------------------------------------------------- */ - -/* Emit bytecode instruction. */ -static BCPos bcemit_INS(FuncState *fs, BCIns ins) -{ - BCPos pc = fs->pc; - LexState *ls = fs->ls; - jmp_patchval(fs, fs->jpc, pc, NO_REG, pc); - fs->jpc = NO_JMP; - if (LJ_UNLIKELY(pc >= fs->bclim)) { - ptrdiff_t base = fs->bcbase - ls->bcstack; - checklimit(fs, ls->sizebcstack, LJ_MAX_BCINS, "bytecode instructions"); - lj_mem_growvec(fs->L, ls->bcstack, ls->sizebcstack, LJ_MAX_BCINS,BCInsLine); - fs->bclim = (BCPos)(ls->sizebcstack - base); - fs->bcbase = ls->bcstack + base; - } - fs->bcbase[pc].ins = ins; - fs->bcbase[pc].line = ls->lastline; - fs->pc = pc+1; - return pc; -} - -#define bcemit_ABC(fs, o, a, b, c) bcemit_INS(fs, BCINS_ABC(o, a, b, c)) -#define bcemit_AD(fs, o, a, d) bcemit_INS(fs, BCINS_AD(o, a, d)) -#define bcemit_AJ(fs, o, a, j) bcemit_INS(fs, BCINS_AJ(o, a, j)) - -#define bcptr(fs, e) (&(fs)->bcbase[(e)->u.s.info].ins) - -/* -- Bytecode emitter for expressions ------------------------------------ */ - -/* Discharge non-constant expression to any register. */ -static void expr_discharge(FuncState *fs, ExpDesc *e) -{ - BCIns ins; - if (e->k == VUPVAL) { - ins = BCINS_AD(BC_UGET, 0, e->u.s.info); - } else if (e->k == VGLOBAL) { - ins = BCINS_AD(BC_GGET, 0, const_str(fs, e)); - } else if (e->k == VINDEXED) { - BCReg rc = e->u.s.aux; - if ((int32_t)rc < 0) { - ins = BCINS_ABC(BC_TGETS, 0, e->u.s.info, ~rc); - } else if (rc > BCMAX_C) { - ins = BCINS_ABC(BC_TGETB, 0, e->u.s.info, rc-(BCMAX_C+1)); - } else { - bcreg_free(fs, rc); - ins = BCINS_ABC(BC_TGETV, 0, e->u.s.info, rc); - } - bcreg_free(fs, e->u.s.info); - } else if (e->k == VCALL) { - e->u.s.info = e->u.s.aux; - e->k = VNONRELOC; - return; - } else if (e->k == VLOCAL) { - e->k = VNONRELOC; - return; - } else { - return; - } - e->u.s.info = bcemit_INS(fs, ins); - e->k = VRELOCABLE; -} - -/* Emit bytecode to set a range of registers to nil. */ -static void bcemit_nil(FuncState *fs, BCReg from, BCReg n) -{ - if (fs->pc > fs->lasttarget) { /* No jumps to current position? */ - BCIns *ip = &fs->bcbase[fs->pc-1].ins; - BCReg pto, pfrom = bc_a(*ip); - switch (bc_op(*ip)) { /* Try to merge with the previous instruction. */ - case BC_KPRI: - if (bc_d(*ip) != ~LJ_TNIL) break; - if (from == pfrom) { - if (n == 1) return; - } else if (from == pfrom+1) { - from = pfrom; - n++; - } else { - break; - } - *ip = BCINS_AD(BC_KNIL, from, from+n-1); /* Replace KPRI. */ - return; - case BC_KNIL: - pto = bc_d(*ip); - if (pfrom <= from && from <= pto+1) { /* Can we connect both ranges? */ - if (from+n-1 > pto) - setbc_d(ip, from+n-1); /* Patch previous instruction range. */ - return; - } - break; - default: - break; - } - } - /* Emit new instruction or replace old instruction. */ - bcemit_INS(fs, n == 1 ? BCINS_AD(BC_KPRI, from, VKNIL) : - BCINS_AD(BC_KNIL, from, from+n-1)); -} - -/* Discharge an expression to a specific register. Ignore branches. */ -static void expr_toreg_nobranch(FuncState *fs, ExpDesc *e, BCReg reg) -{ - BCIns ins; - expr_discharge(fs, e); - if (e->k == VKSTR) { - ins = BCINS_AD(BC_KSTR, reg, const_str(fs, e)); - } else if (e->k == VKNUM) { -#if LJ_DUALNUM - cTValue *tv = expr_numtv(e); - if (tvisint(tv) && checki16(intV(tv))) - ins = BCINS_AD(BC_KSHORT, reg, (BCReg)(uint16_t)intV(tv)); - else -#else - lua_Number n = expr_numberV(e); - int32_t k = lj_num2int(n); - if (checki16(k) && n == (lua_Number)k) - ins = BCINS_AD(BC_KSHORT, reg, (BCReg)(uint16_t)k); - else -#endif - ins = BCINS_AD(BC_KNUM, reg, const_num(fs, e)); -#if LJ_HASFFI - } else if (e->k == VKCDATA) { - fs->flags |= PROTO_FFI; - ins = BCINS_AD(BC_KCDATA, reg, - const_gc(fs, obj2gco(cdataV(&e->u.nval)), LJ_TCDATA)); -#endif - } else if (e->k == VRELOCABLE) { - setbc_a(bcptr(fs, e), reg); - goto noins; - } else if (e->k == VNONRELOC) { - if (reg == e->u.s.info) - goto noins; - ins = BCINS_AD(BC_MOV, reg, e->u.s.info); - } else if (e->k == VKNIL) { - bcemit_nil(fs, reg, 1); - goto noins; - } else if (e->k <= VKTRUE) { - ins = BCINS_AD(BC_KPRI, reg, const_pri(e)); - } else { - lua_assert(e->k == VVOID || e->k == VJMP); - return; - } - bcemit_INS(fs, ins); -noins: - e->u.s.info = reg; - e->k = VNONRELOC; -} - -/* Forward declaration. */ -static BCPos bcemit_jmp(FuncState *fs); - -/* Discharge an expression to a specific register. */ -static void expr_toreg(FuncState *fs, ExpDesc *e, BCReg reg) -{ - expr_toreg_nobranch(fs, e, reg); - if (e->k == VJMP) - jmp_append(fs, &e->t, e->u.s.info); /* Add it to the true jump list. */ - if (expr_hasjump(e)) { /* Discharge expression with branches. */ - BCPos jend, jfalse = NO_JMP, jtrue = NO_JMP; - if (jmp_novalue(fs, e->t) || jmp_novalue(fs, e->f)) { - BCPos jval = (e->k == VJMP) ? NO_JMP : bcemit_jmp(fs); - jfalse = bcemit_AD(fs, BC_KPRI, reg, VKFALSE); - bcemit_AJ(fs, BC_JMP, fs->freereg, 1); - jtrue = bcemit_AD(fs, BC_KPRI, reg, VKTRUE); - jmp_tohere(fs, jval); - } - jend = fs->pc; - fs->lasttarget = jend; - jmp_patchval(fs, e->f, jend, reg, jfalse); - jmp_patchval(fs, e->t, jend, reg, jtrue); - } - e->f = e->t = NO_JMP; - e->u.s.info = reg; - e->k = VNONRELOC; -} - -/* Discharge an expression to the next free register. */ -static void expr_tonextreg(FuncState *fs, ExpDesc *e) -{ - expr_discharge(fs, e); - expr_free(fs, e); - bcreg_reserve(fs, 1); - expr_toreg(fs, e, fs->freereg - 1); -} - -/* Discharge an expression to any register. */ -static BCReg expr_toanyreg(FuncState *fs, ExpDesc *e) -{ - expr_discharge(fs, e); - if (e->k == VNONRELOC) { - if (!expr_hasjump(e)) return e->u.s.info; /* Already in a register. */ - if (e->u.s.info >= fs->nactvar) { - expr_toreg(fs, e, e->u.s.info); /* Discharge to temp. register. */ - return e->u.s.info; - } - } - expr_tonextreg(fs, e); /* Discharge to next register. */ - return e->u.s.info; -} - -/* Partially discharge expression to a value. */ -static void expr_toval(FuncState *fs, ExpDesc *e) -{ - if (expr_hasjump(e)) - expr_toanyreg(fs, e); - else - expr_discharge(fs, e); -} - -/* Emit store for LHS expression. */ -static void bcemit_store(FuncState *fs, ExpDesc *var, ExpDesc *e) -{ - BCIns ins; - if (var->k == VLOCAL) { - fs->ls->vstack[var->u.s.aux].info |= VSTACK_VAR_RW; - expr_free(fs, e); - expr_toreg(fs, e, var->u.s.info); - return; - } else if (var->k == VUPVAL) { - fs->ls->vstack[var->u.s.aux].info |= VSTACK_VAR_RW; - expr_toval(fs, e); - if (e->k <= VKTRUE) - ins = BCINS_AD(BC_USETP, var->u.s.info, const_pri(e)); - else if (e->k == VKSTR) - ins = BCINS_AD(BC_USETS, var->u.s.info, const_str(fs, e)); - else if (e->k == VKNUM) - ins = BCINS_AD(BC_USETN, var->u.s.info, const_num(fs, e)); - else - ins = BCINS_AD(BC_USETV, var->u.s.info, expr_toanyreg(fs, e)); - } else if (var->k == VGLOBAL) { - BCReg ra = expr_toanyreg(fs, e); - ins = BCINS_AD(BC_GSET, ra, const_str(fs, var)); - } else { - BCReg ra, rc; - lua_assert(var->k == VINDEXED); - ra = expr_toanyreg(fs, e); - rc = var->u.s.aux; - if ((int32_t)rc < 0) { - ins = BCINS_ABC(BC_TSETS, ra, var->u.s.info, ~rc); - } else if (rc > BCMAX_C) { - ins = BCINS_ABC(BC_TSETB, ra, var->u.s.info, rc-(BCMAX_C+1)); - } else { - /* Free late alloced key reg to avoid assert on free of value reg. */ - /* This can only happen when called from expr_table(). */ - lua_assert(e->k != VNONRELOC || ra < fs->nactvar || - rc < ra || (bcreg_free(fs, rc),1)); - ins = BCINS_ABC(BC_TSETV, ra, var->u.s.info, rc); - } - } - bcemit_INS(fs, ins); - expr_free(fs, e); -} - -/* Emit method lookup expression. */ -static void bcemit_method(FuncState *fs, ExpDesc *e, ExpDesc *key) -{ - BCReg idx, func, obj = expr_toanyreg(fs, e); - expr_free(fs, e); - func = fs->freereg; - bcemit_AD(fs, BC_MOV, func+1+LJ_FR2, obj); /* Copy object to 1st argument. */ - lua_assert(expr_isstrk(key)); - idx = const_str(fs, key); - if (idx <= BCMAX_C) { - bcreg_reserve(fs, 2+LJ_FR2); - bcemit_ABC(fs, BC_TGETS, func, obj, idx); - } else { - bcreg_reserve(fs, 3+LJ_FR2); - bcemit_AD(fs, BC_KSTR, func+2+LJ_FR2, idx); - bcemit_ABC(fs, BC_TGETV, func, obj, func+2+LJ_FR2); - fs->freereg--; - } - e->u.s.info = func; - e->k = VNONRELOC; -} - -/* -- Bytecode emitter for branches --------------------------------------- */ - -/* Emit unconditional branch. */ -static BCPos bcemit_jmp(FuncState *fs) -{ - BCPos jpc = fs->jpc; - BCPos j = fs->pc - 1; - BCIns *ip = &fs->bcbase[j].ins; - fs->jpc = NO_JMP; - if ((int32_t)j >= (int32_t)fs->lasttarget && bc_op(*ip) == BC_UCLO) { - setbc_j(ip, NO_JMP); - fs->lasttarget = j+1; - } else { - j = bcemit_AJ(fs, BC_JMP, fs->freereg, NO_JMP); - } - jmp_append(fs, &j, jpc); - return j; -} - -/* Invert branch condition of bytecode instruction. */ -static void invertcond(FuncState *fs, ExpDesc *e) -{ - BCIns *ip = &fs->bcbase[e->u.s.info - 1].ins; - setbc_op(ip, bc_op(*ip)^1); -} - -/* Emit conditional branch. */ -static BCPos bcemit_branch(FuncState *fs, ExpDesc *e, int cond) -{ - BCPos pc; - if (e->k == VRELOCABLE) { - BCIns *ip = bcptr(fs, e); - if (bc_op(*ip) == BC_NOT) { - *ip = BCINS_AD(cond ? BC_ISF : BC_IST, 0, bc_d(*ip)); - return bcemit_jmp(fs); - } - } - if (e->k != VNONRELOC) { - bcreg_reserve(fs, 1); - expr_toreg_nobranch(fs, e, fs->freereg-1); - } - bcemit_AD(fs, cond ? BC_ISTC : BC_ISFC, NO_REG, e->u.s.info); - pc = bcemit_jmp(fs); - expr_free(fs, e); - return pc; -} - -/* Emit branch on true condition. */ -static void bcemit_branch_t(FuncState *fs, ExpDesc *e) -{ - BCPos pc; - expr_discharge(fs, e); - if (e->k == VKSTR || e->k == VKNUM || e->k == VKTRUE) - pc = NO_JMP; /* Never jump. */ - else if (e->k == VJMP) - invertcond(fs, e), pc = e->u.s.info; - else if (e->k == VKFALSE || e->k == VKNIL) - expr_toreg_nobranch(fs, e, NO_REG), pc = bcemit_jmp(fs); - else - pc = bcemit_branch(fs, e, 0); - jmp_append(fs, &e->f, pc); - jmp_tohere(fs, e->t); - e->t = NO_JMP; -} - -/* Emit branch on false condition. */ -static void bcemit_branch_f(FuncState *fs, ExpDesc *e) -{ - BCPos pc; - expr_discharge(fs, e); - if (e->k == VKNIL || e->k == VKFALSE) - pc = NO_JMP; /* Never jump. */ - else if (e->k == VJMP) - pc = e->u.s.info; - else if (e->k == VKSTR || e->k == VKNUM || e->k == VKTRUE) - expr_toreg_nobranch(fs, e, NO_REG), pc = bcemit_jmp(fs); - else - pc = bcemit_branch(fs, e, 1); - jmp_append(fs, &e->t, pc); - jmp_tohere(fs, e->f); - e->f = NO_JMP; -} - -/* -- Bytecode emitter for operators -------------------------------------- */ - -/* Try constant-folding of arithmetic operators. */ -static int foldarith(BinOpr opr, ExpDesc *e1, ExpDesc *e2) -{ - TValue o; - lua_Number n; - if (!expr_isnumk_nojump(e1) || !expr_isnumk_nojump(e2)) return 0; - n = lj_vm_foldarith(expr_numberV(e1), expr_numberV(e2), (int)opr-OPR_ADD); - setnumV(&o, n); - if (tvisnan(&o) || tvismzero(&o)) return 0; /* Avoid NaN and -0 as consts. */ - if (LJ_DUALNUM) { - int32_t k = lj_num2int(n); - if ((lua_Number)k == n) { - setintV(&e1->u.nval, k); - return 1; - } - } - setnumV(&e1->u.nval, n); - return 1; -} - -/* Emit arithmetic operator. */ -static void bcemit_arith(FuncState *fs, BinOpr opr, ExpDesc *e1, ExpDesc *e2) -{ - BCReg rb, rc, t; - uint32_t op; - if (foldarith(opr, e1, e2)) - return; - if (opr == OPR_POW) { - op = BC_POW; - rc = expr_toanyreg(fs, e2); - rb = expr_toanyreg(fs, e1); - } else { - op = opr-OPR_ADD+BC_ADDVV; - /* Must discharge 2nd operand first since VINDEXED might free regs. */ - expr_toval(fs, e2); - if (expr_isnumk(e2) && (rc = const_num(fs, e2)) <= BCMAX_C) - op -= BC_ADDVV-BC_ADDVN; - else - rc = expr_toanyreg(fs, e2); - /* 1st operand discharged by bcemit_binop_left, but need KNUM/KSHORT. */ - lua_assert(expr_isnumk(e1) || e1->k == VNONRELOC); - expr_toval(fs, e1); - /* Avoid two consts to satisfy bytecode constraints. */ - if (expr_isnumk(e1) && !expr_isnumk(e2) && - (t = const_num(fs, e1)) <= BCMAX_B) { - rb = rc; rc = t; op -= BC_ADDVV-BC_ADDNV; - } else { - rb = expr_toanyreg(fs, e1); - } - } - /* Using expr_free might cause asserts if the order is wrong. */ - if (e1->k == VNONRELOC && e1->u.s.info >= fs->nactvar) fs->freereg--; - if (e2->k == VNONRELOC && e2->u.s.info >= fs->nactvar) fs->freereg--; - e1->u.s.info = bcemit_ABC(fs, op, 0, rb, rc); - e1->k = VRELOCABLE; -} - -/* Emit comparison operator. */ -static void bcemit_comp(FuncState *fs, BinOpr opr, ExpDesc *e1, ExpDesc *e2) -{ - ExpDesc *eret = e1; - BCIns ins; - expr_toval(fs, e1); - if (opr == OPR_EQ || opr == OPR_NE) { - BCOp op = opr == OPR_EQ ? BC_ISEQV : BC_ISNEV; - BCReg ra; - if (expr_isk(e1)) { e1 = e2; e2 = eret; } /* Need constant in 2nd arg. */ - ra = expr_toanyreg(fs, e1); /* First arg must be in a reg. */ - expr_toval(fs, e2); - switch (e2->k) { - case VKNIL: case VKFALSE: case VKTRUE: - ins = BCINS_AD(op+(BC_ISEQP-BC_ISEQV), ra, const_pri(e2)); - break; - case VKSTR: - ins = BCINS_AD(op+(BC_ISEQS-BC_ISEQV), ra, const_str(fs, e2)); - break; - case VKNUM: - ins = BCINS_AD(op+(BC_ISEQN-BC_ISEQV), ra, const_num(fs, e2)); - break; - default: - ins = BCINS_AD(op, ra, expr_toanyreg(fs, e2)); - break; - } - } else { - uint32_t op = opr-OPR_LT+BC_ISLT; - BCReg ra, rd; - if ((op-BC_ISLT) & 1) { /* GT -> LT, GE -> LE */ - e1 = e2; e2 = eret; /* Swap operands. */ - op = ((op-BC_ISLT)^3)+BC_ISLT; - expr_toval(fs, e1); - } - rd = expr_toanyreg(fs, e2); - ra = expr_toanyreg(fs, e1); - ins = BCINS_AD(op, ra, rd); - } - /* Using expr_free might cause asserts if the order is wrong. */ - if (e1->k == VNONRELOC && e1->u.s.info >= fs->nactvar) fs->freereg--; - if (e2->k == VNONRELOC && e2->u.s.info >= fs->nactvar) fs->freereg--; - bcemit_INS(fs, ins); - eret->u.s.info = bcemit_jmp(fs); - eret->k = VJMP; -} - -/* Fixup left side of binary operator. */ -static void bcemit_binop_left(FuncState *fs, BinOpr op, ExpDesc *e) -{ - if (op == OPR_AND) { - bcemit_branch_t(fs, e); - } else if (op == OPR_OR) { - bcemit_branch_f(fs, e); - } else if (op == OPR_CONCAT) { - expr_tonextreg(fs, e); - } else if (op == OPR_EQ || op == OPR_NE) { - if (!expr_isk_nojump(e)) expr_toanyreg(fs, e); - } else { - if (!expr_isnumk_nojump(e)) expr_toanyreg(fs, e); - } -} - -/* Emit binary operator. */ -static void bcemit_binop(FuncState *fs, BinOpr op, ExpDesc *e1, ExpDesc *e2) -{ - if (op <= OPR_POW) { - bcemit_arith(fs, op, e1, e2); - } else if (op == OPR_AND) { - lua_assert(e1->t == NO_JMP); /* List must be closed. */ - expr_discharge(fs, e2); - jmp_append(fs, &e2->f, e1->f); - *e1 = *e2; - } else if (op == OPR_OR) { - lua_assert(e1->f == NO_JMP); /* List must be closed. */ - expr_discharge(fs, e2); - jmp_append(fs, &e2->t, e1->t); - *e1 = *e2; - } else if (op == OPR_CONCAT) { - expr_toval(fs, e2); - if (e2->k == VRELOCABLE && bc_op(*bcptr(fs, e2)) == BC_CAT) { - lua_assert(e1->u.s.info == bc_b(*bcptr(fs, e2))-1); - expr_free(fs, e1); - setbc_b(bcptr(fs, e2), e1->u.s.info); - e1->u.s.info = e2->u.s.info; - } else { - expr_tonextreg(fs, e2); - expr_free(fs, e2); - expr_free(fs, e1); - e1->u.s.info = bcemit_ABC(fs, BC_CAT, 0, e1->u.s.info, e2->u.s.info); - } - e1->k = VRELOCABLE; - } else { - lua_assert(op == OPR_NE || op == OPR_EQ || - op == OPR_LT || op == OPR_GE || op == OPR_LE || op == OPR_GT); - bcemit_comp(fs, op, e1, e2); - } -} - -/* Emit unary operator. */ -static void bcemit_unop(FuncState *fs, BCOp op, ExpDesc *e) -{ - if (op == BC_NOT) { - /* Swap true and false lists. */ - { BCPos temp = e->f; e->f = e->t; e->t = temp; } - jmp_dropval(fs, e->f); - jmp_dropval(fs, e->t); - expr_discharge(fs, e); - if (e->k == VKNIL || e->k == VKFALSE) { - e->k = VKTRUE; - return; - } else if (expr_isk(e) || (LJ_HASFFI && e->k == VKCDATA)) { - e->k = VKFALSE; - return; - } else if (e->k == VJMP) { - invertcond(fs, e); - return; - } else if (e->k == VRELOCABLE) { - bcreg_reserve(fs, 1); - setbc_a(bcptr(fs, e), fs->freereg-1); - e->u.s.info = fs->freereg-1; - e->k = VNONRELOC; - } else { - lua_assert(e->k == VNONRELOC); - } - } else { - lua_assert(op == BC_UNM || op == BC_LEN); - if (op == BC_UNM && !expr_hasjump(e)) { /* Constant-fold negations. */ -#if LJ_HASFFI - if (e->k == VKCDATA) { /* Fold in-place since cdata is not interned. */ - GCcdata *cd = cdataV(&e->u.nval); - int64_t *p = (int64_t *)cdataptr(cd); - if (cd->ctypeid == CTID_COMPLEX_DOUBLE) - p[1] ^= (int64_t)U64x(80000000,00000000); - else - *p = -*p; - return; - } else -#endif - if (expr_isnumk(e) && !expr_numiszero(e)) { /* Avoid folding to -0. */ - TValue *o = expr_numtv(e); - if (tvisint(o)) { - int32_t k = intV(o); - if (k == -k) - setnumV(o, -(lua_Number)k); - else - setintV(o, -k); - return; - } else { - o->u64 ^= U64x(80000000,00000000); - return; - } - } - } - expr_toanyreg(fs, e); - } - expr_free(fs, e); - e->u.s.info = bcemit_AD(fs, op, 0, e->u.s.info); - e->k = VRELOCABLE; -} - -/* -- Lexer support ------------------------------------------------------- */ - -/* Check and consume optional token. */ -static int lex_opt(LexState *ls, LexToken tok) -{ - if (ls->tok == tok) { - lj_lex_next(ls); - return 1; - } - return 0; -} - -/* Check and consume token. */ -static void lex_check(LexState *ls, LexToken tok) -{ - if (ls->tok != tok) - err_token(ls, tok); - lj_lex_next(ls); -} - -/* Check for matching token. */ -static void lex_match(LexState *ls, LexToken what, LexToken who, BCLine line) -{ - if (!lex_opt(ls, what)) { - if (line == ls->linenumber) { - err_token(ls, what); - } else { - const char *swhat = lj_lex_token2str(ls, what); - const char *swho = lj_lex_token2str(ls, who); - lj_lex_error(ls, ls->tok, LJ_ERR_XMATCH, swhat, swho, line); - } - } -} - -/* Check for string token. */ -static GCstr *lex_str(LexState *ls) -{ - GCstr *s; - if (ls->tok != TK_name && (LJ_52 || ls->tok != TK_goto)) - err_token(ls, TK_name); - s = strV(&ls->tokval); - lj_lex_next(ls); - return s; -} - -/* -- Variable handling --------------------------------------------------- */ - -#define var_get(ls, fs, i) ((ls)->vstack[(fs)->varmap[(i)]]) - -/* Define a new local variable. */ -static void var_new(LexState *ls, BCReg n, GCstr *name) -{ - FuncState *fs = ls->fs; - MSize vtop = ls->vtop; - checklimit(fs, fs->nactvar+n, LJ_MAX_LOCVAR, "local variables"); - if (LJ_UNLIKELY(vtop >= ls->sizevstack)) { - if (ls->sizevstack >= LJ_MAX_VSTACK) - lj_lex_error(ls, 0, LJ_ERR_XLIMC, LJ_MAX_VSTACK); - lj_mem_growvec(ls->L, ls->vstack, ls->sizevstack, LJ_MAX_VSTACK, VarInfo); - } - lua_assert((uintptr_t)name < VARNAME__MAX || - lj_tab_getstr(fs->kt, name) != NULL); - /* NOBARRIER: name is anchored in fs->kt and ls->vstack is not a GCobj. */ - setgcref(ls->vstack[vtop].name, obj2gco(name)); - fs->varmap[fs->nactvar+n] = (uint16_t)vtop; - ls->vtop = vtop+1; -} - -#define var_new_lit(ls, n, v) \ - var_new(ls, (n), lj_parse_keepstr(ls, "" v, sizeof(v)-1)) - -#define var_new_fixed(ls, n, vn) \ - var_new(ls, (n), (GCstr *)(uintptr_t)(vn)) - -/* Add local variables. */ -static void var_add(LexState *ls, BCReg nvars) -{ - FuncState *fs = ls->fs; - BCReg nactvar = fs->nactvar; - while (nvars--) { - VarInfo *v = &var_get(ls, fs, nactvar); - v->startpc = fs->pc; - v->slot = nactvar++; - v->info = 0; - } - fs->nactvar = nactvar; -} - -/* Remove local variables. */ -static void var_remove(LexState *ls, BCReg tolevel) -{ - FuncState *fs = ls->fs; - while (fs->nactvar > tolevel) - var_get(ls, fs, --fs->nactvar).endpc = fs->pc; -} - -/* Lookup local variable name. */ -static BCReg var_lookup_local(FuncState *fs, GCstr *n) -{ - int i; - for (i = fs->nactvar-1; i >= 0; i--) { - if (n == strref(var_get(fs->ls, fs, i).name)) - return (BCReg)i; - } - return (BCReg)-1; /* Not found. */ -} - -/* Lookup or add upvalue index. */ -static MSize var_lookup_uv(FuncState *fs, MSize vidx, ExpDesc *e) -{ - MSize i, n = fs->nuv; - for (i = 0; i < n; i++) - if (fs->uvmap[i] == vidx) - return i; /* Already exists. */ - /* Otherwise create a new one. */ - checklimit(fs, fs->nuv, LJ_MAX_UPVAL, "upvalues"); - lua_assert(e->k == VLOCAL || e->k == VUPVAL); - fs->uvmap[n] = (uint16_t)vidx; - fs->uvtmp[n] = (uint16_t)(e->k == VLOCAL ? vidx : LJ_MAX_VSTACK+e->u.s.info); - fs->nuv = n+1; - return n; -} - -/* Forward declaration. */ -static void fscope_uvmark(FuncState *fs, BCReg level); - -/* Recursively lookup variables in enclosing functions. */ -static MSize var_lookup_(FuncState *fs, GCstr *name, ExpDesc *e, int first) -{ - if (fs) { - BCReg reg = var_lookup_local(fs, name); - if ((int32_t)reg >= 0) { /* Local in this function? */ - expr_init(e, VLOCAL, reg); - if (!first) - fscope_uvmark(fs, reg); /* Scope now has an upvalue. */ - return (MSize)(e->u.s.aux = (uint32_t)fs->varmap[reg]); - } else { - MSize vidx = var_lookup_(fs->prev, name, e, 0); /* Var in outer func? */ - if ((int32_t)vidx >= 0) { /* Yes, make it an upvalue here. */ - e->u.s.info = (uint8_t)var_lookup_uv(fs, vidx, e); - e->k = VUPVAL; - return vidx; - } - } - } else { /* Not found in any function, must be a global. */ - expr_init(e, VGLOBAL, 0); - e->u.sval = name; - } - return (MSize)-1; /* Global. */ -} - -/* Lookup variable name. */ -#define var_lookup(ls, e) \ - var_lookup_((ls)->fs, lex_str(ls), (e), 1) - -/* -- Goto an label handling ---------------------------------------------- */ - -/* Add a new goto or label. */ -static MSize gola_new(LexState *ls, GCstr *name, uint8_t info, BCPos pc) -{ - FuncState *fs = ls->fs; - MSize vtop = ls->vtop; - if (LJ_UNLIKELY(vtop >= ls->sizevstack)) { - if (ls->sizevstack >= LJ_MAX_VSTACK) - lj_lex_error(ls, 0, LJ_ERR_XLIMC, LJ_MAX_VSTACK); - lj_mem_growvec(ls->L, ls->vstack, ls->sizevstack, LJ_MAX_VSTACK, VarInfo); - } - lua_assert(name == NAME_BREAK || lj_tab_getstr(fs->kt, name) != NULL); - /* NOBARRIER: name is anchored in fs->kt and ls->vstack is not a GCobj. */ - setgcref(ls->vstack[vtop].name, obj2gco(name)); - ls->vstack[vtop].startpc = pc; - ls->vstack[vtop].slot = (uint8_t)fs->nactvar; - ls->vstack[vtop].info = info; - ls->vtop = vtop+1; - return vtop; -} - -#define gola_isgoto(v) ((v)->info & VSTACK_GOTO) -#define gola_islabel(v) ((v)->info & VSTACK_LABEL) -#define gola_isgotolabel(v) ((v)->info & (VSTACK_GOTO|VSTACK_LABEL)) - -/* Patch goto to jump to label. */ -static void gola_patch(LexState *ls, VarInfo *vg, VarInfo *vl) -{ - FuncState *fs = ls->fs; - BCPos pc = vg->startpc; - setgcrefnull(vg->name); /* Invalidate pending goto. */ - setbc_a(&fs->bcbase[pc].ins, vl->slot); - jmp_patch(fs, pc, vl->startpc); -} - -/* Patch goto to close upvalues. */ -static void gola_close(LexState *ls, VarInfo *vg) -{ - FuncState *fs = ls->fs; - BCPos pc = vg->startpc; - BCIns *ip = &fs->bcbase[pc].ins; - lua_assert(gola_isgoto(vg)); - lua_assert(bc_op(*ip) == BC_JMP || bc_op(*ip) == BC_UCLO); - setbc_a(ip, vg->slot); - if (bc_op(*ip) == BC_JMP) { - BCPos next = jmp_next(fs, pc); - if (next != NO_JMP) jmp_patch(fs, next, pc); /* Jump to UCLO. */ - setbc_op(ip, BC_UCLO); /* Turn into UCLO. */ - setbc_j(ip, NO_JMP); - } -} - -/* Resolve pending forward gotos for label. */ -static void gola_resolve(LexState *ls, FuncScope *bl, MSize idx) -{ - VarInfo *vg = ls->vstack + bl->vstart; - VarInfo *vl = ls->vstack + idx; - for (; vg < vl; vg++) - if (gcrefeq(vg->name, vl->name) && gola_isgoto(vg)) { - if (vg->slot < vl->slot) { - GCstr *name = strref(var_get(ls, ls->fs, vg->slot).name); - lua_assert((uintptr_t)name >= VARNAME__MAX); - ls->linenumber = ls->fs->bcbase[vg->startpc].line; - lua_assert(strref(vg->name) != NAME_BREAK); - lj_lex_error(ls, 0, LJ_ERR_XGSCOPE, - strdata(strref(vg->name)), strdata(name)); - } - gola_patch(ls, vg, vl); - } -} - -/* Fixup remaining gotos and labels for scope. */ -static void gola_fixup(LexState *ls, FuncScope *bl) -{ - VarInfo *v = ls->vstack + bl->vstart; - VarInfo *ve = ls->vstack + ls->vtop; - for (; v < ve; v++) { - GCstr *name = strref(v->name); - if (name != NULL) { /* Only consider remaining valid gotos/labels. */ - if (gola_islabel(v)) { - VarInfo *vg; - setgcrefnull(v->name); /* Invalidate label that goes out of scope. */ - for (vg = v+1; vg < ve; vg++) /* Resolve pending backward gotos. */ - if (strref(vg->name) == name && gola_isgoto(vg)) { - if ((bl->flags&FSCOPE_UPVAL) && vg->slot > v->slot) - gola_close(ls, vg); - gola_patch(ls, vg, v); - } - } else if (gola_isgoto(v)) { - if (bl->prev) { /* Propagate goto or break to outer scope. */ - bl->prev->flags |= name == NAME_BREAK ? FSCOPE_BREAK : FSCOPE_GOLA; - v->slot = bl->nactvar; - if ((bl->flags & FSCOPE_UPVAL)) - gola_close(ls, v); - } else { /* No outer scope: undefined goto label or no loop. */ - ls->linenumber = ls->fs->bcbase[v->startpc].line; - if (name == NAME_BREAK) - lj_lex_error(ls, 0, LJ_ERR_XBREAK); - else - lj_lex_error(ls, 0, LJ_ERR_XLUNDEF, strdata(name)); - } - } - } - } -} - -/* Find existing label. */ -static VarInfo *gola_findlabel(LexState *ls, GCstr *name) -{ - VarInfo *v = ls->vstack + ls->fs->bl->vstart; - VarInfo *ve = ls->vstack + ls->vtop; - for (; v < ve; v++) - if (strref(v->name) == name && gola_islabel(v)) - return v; - return NULL; -} - -/* -- Scope handling ------------------------------------------------------ */ - -/* Begin a scope. */ -static void fscope_begin(FuncState *fs, FuncScope *bl, int flags) -{ - bl->nactvar = (uint8_t)fs->nactvar; - bl->flags = flags; - bl->vstart = fs->ls->vtop; - bl->prev = fs->bl; - fs->bl = bl; - lua_assert(fs->freereg == fs->nactvar); -} - -/* End a scope. */ -static void fscope_end(FuncState *fs) -{ - FuncScope *bl = fs->bl; - LexState *ls = fs->ls; - fs->bl = bl->prev; - var_remove(ls, bl->nactvar); - fs->freereg = fs->nactvar; - lua_assert(bl->nactvar == fs->nactvar); - if ((bl->flags & (FSCOPE_UPVAL|FSCOPE_NOCLOSE)) == FSCOPE_UPVAL) - bcemit_AJ(fs, BC_UCLO, bl->nactvar, 0); - if ((bl->flags & FSCOPE_BREAK)) { - if ((bl->flags & FSCOPE_LOOP)) { - MSize idx = gola_new(ls, NAME_BREAK, VSTACK_LABEL, fs->pc); - ls->vtop = idx; /* Drop break label immediately. */ - gola_resolve(ls, bl, idx); - } else { /* Need the fixup step to propagate the breaks. */ - gola_fixup(ls, bl); - return; - } - } - if ((bl->flags & FSCOPE_GOLA)) { - gola_fixup(ls, bl); - } -} - -/* Mark scope as having an upvalue. */ -static void fscope_uvmark(FuncState *fs, BCReg level) -{ - FuncScope *bl; - for (bl = fs->bl; bl && bl->nactvar > level; bl = bl->prev) - ; - if (bl) - bl->flags |= FSCOPE_UPVAL; -} - -/* -- Function state management ------------------------------------------- */ - -/* Fixup bytecode for prototype. */ -static void fs_fixup_bc(FuncState *fs, GCproto *pt, BCIns *bc, MSize n) -{ - BCInsLine *base = fs->bcbase; - MSize i; - pt->sizebc = n; - bc[0] = BCINS_AD((fs->flags & PROTO_VARARG) ? BC_FUNCV : BC_FUNCF, - fs->framesize, 0); - for (i = 1; i < n; i++) - bc[i] = base[i].ins; -} - -/* Fixup upvalues for child prototype, step #2. */ -static void fs_fixup_uv2(FuncState *fs, GCproto *pt) -{ - VarInfo *vstack = fs->ls->vstack; - uint16_t *uv = proto_uv(pt); - MSize i, n = pt->sizeuv; - for (i = 0; i < n; i++) { - VarIndex vidx = uv[i]; - if (vidx >= LJ_MAX_VSTACK) - uv[i] = vidx - LJ_MAX_VSTACK; - else if ((vstack[vidx].info & VSTACK_VAR_RW)) - uv[i] = vstack[vidx].slot | PROTO_UV_LOCAL; - else - uv[i] = vstack[vidx].slot | PROTO_UV_LOCAL | PROTO_UV_IMMUTABLE; - } -} - -/* Fixup constants for prototype. */ -static void fs_fixup_k(FuncState *fs, GCproto *pt, void *kptr) -{ - GCtab *kt; - TValue *array; - Node *node; - MSize i, hmask; - checklimitgt(fs, fs->nkn, BCMAX_D+1, "constants"); - checklimitgt(fs, fs->nkgc, BCMAX_D+1, "constants"); - setmref(pt->k, kptr); - pt->sizekn = fs->nkn; - pt->sizekgc = fs->nkgc; - kt = fs->kt; - array = tvref(kt->array); - for (i = 0; i < kt->asize; i++) - if (tvhaskslot(&array[i])) { - TValue *tv = &((TValue *)kptr)[tvkslot(&array[i])]; - if (LJ_DUALNUM) - setintV(tv, (int32_t)i); - else - setnumV(tv, (lua_Number)i); - } - node = noderef(kt->node); - hmask = kt->hmask; - for (i = 0; i <= hmask; i++) { - Node *n = &node[i]; - if (tvhaskslot(&n->val)) { - ptrdiff_t kidx = (ptrdiff_t)tvkslot(&n->val); - lua_assert(!tvisint(&n->key)); - if (tvisnum(&n->key)) { - TValue *tv = &((TValue *)kptr)[kidx]; - if (LJ_DUALNUM) { - lua_Number nn = numV(&n->key); - int32_t k = lj_num2int(nn); - lua_assert(!tvismzero(&n->key)); - if ((lua_Number)k == nn) - setintV(tv, k); - else - *tv = n->key; - } else { - *tv = n->key; - } - } else { - GCobj *o = gcV(&n->key); - setgcref(((GCRef *)kptr)[~kidx], o); - lj_gc_objbarrier(fs->L, pt, o); - if (tvisproto(&n->key)) - fs_fixup_uv2(fs, gco2pt(o)); - } - } - } -} - -/* Fixup upvalues for prototype, step #1. */ -static void fs_fixup_uv1(FuncState *fs, GCproto *pt, uint16_t *uv) -{ - setmref(pt->uv, uv); - pt->sizeuv = fs->nuv; - memcpy(uv, fs->uvtmp, fs->nuv*sizeof(VarIndex)); -} - -#ifndef LUAJIT_DISABLE_DEBUGINFO -/* Prepare lineinfo for prototype. */ -static size_t fs_prep_line(FuncState *fs, BCLine numline) -{ - return (fs->pc-1) << (numline < 256 ? 0 : numline < 65536 ? 1 : 2); -} - -/* Fixup lineinfo for prototype. */ -static void fs_fixup_line(FuncState *fs, GCproto *pt, - void *lineinfo, BCLine numline) -{ - BCInsLine *base = fs->bcbase + 1; - BCLine first = fs->linedefined; - MSize i = 0, n = fs->pc-1; - pt->firstline = fs->linedefined; - pt->numline = numline; - setmref(pt->lineinfo, lineinfo); - if (LJ_LIKELY(numline < 256)) { - uint8_t *li = (uint8_t *)lineinfo; - do { - BCLine delta = base[i].line - first; - lua_assert(delta >= 0 && delta < 256); - li[i] = (uint8_t)delta; - } while (++i < n); - } else if (LJ_LIKELY(numline < 65536)) { - uint16_t *li = (uint16_t *)lineinfo; - do { - BCLine delta = base[i].line - first; - lua_assert(delta >= 0 && delta < 65536); - li[i] = (uint16_t)delta; - } while (++i < n); - } else { - uint32_t *li = (uint32_t *)lineinfo; - do { - BCLine delta = base[i].line - first; - lua_assert(delta >= 0); - li[i] = (uint32_t)delta; - } while (++i < n); - } -} - -/* Prepare variable info for prototype. */ -static size_t fs_prep_var(LexState *ls, FuncState *fs, size_t *ofsvar) -{ - VarInfo *vs =ls->vstack, *ve; - MSize i, n; - BCPos lastpc; - lj_buf_reset(&ls->sb); /* Copy to temp. string buffer. */ - /* Store upvalue names. */ - for (i = 0, n = fs->nuv; i < n; i++) { - GCstr *s = strref(vs[fs->uvmap[i]].name); - MSize len = s->len+1; - char *p = lj_buf_more(&ls->sb, len); - p = lj_buf_wmem(p, strdata(s), len); - setsbufP(&ls->sb, p); - } - *ofsvar = sbuflen(&ls->sb); - lastpc = 0; - /* Store local variable names and compressed ranges. */ - for (ve = vs + ls->vtop, vs += fs->vbase; vs < ve; vs++) { - if (!gola_isgotolabel(vs)) { - GCstr *s = strref(vs->name); - BCPos startpc; - char *p; - if ((uintptr_t)s < VARNAME__MAX) { - p = lj_buf_more(&ls->sb, 1 + 2*5); - *p++ = (char)(uintptr_t)s; - } else { - MSize len = s->len+1; - p = lj_buf_more(&ls->sb, len + 2*5); - p = lj_buf_wmem(p, strdata(s), len); - } - startpc = vs->startpc; - p = lj_strfmt_wuleb128(p, startpc-lastpc); - p = lj_strfmt_wuleb128(p, vs->endpc-startpc); - setsbufP(&ls->sb, p); - lastpc = startpc; - } - } - lj_buf_putb(&ls->sb, '\0'); /* Terminator for varinfo. */ - return sbuflen(&ls->sb); -} - -/* Fixup variable info for prototype. */ -static void fs_fixup_var(LexState *ls, GCproto *pt, uint8_t *p, size_t ofsvar) -{ - setmref(pt->uvinfo, p); - setmref(pt->varinfo, (char *)p + ofsvar); - memcpy(p, sbufB(&ls->sb), sbuflen(&ls->sb)); /* Copy from temp. buffer. */ -} -#else - -/* Initialize with empty debug info, if disabled. */ -#define fs_prep_line(fs, numline) (UNUSED(numline), 0) -#define fs_fixup_line(fs, pt, li, numline) \ - pt->firstline = pt->numline = 0, setmref((pt)->lineinfo, NULL) -#define fs_prep_var(ls, fs, ofsvar) (UNUSED(ofsvar), 0) -#define fs_fixup_var(ls, pt, p, ofsvar) \ - setmref((pt)->uvinfo, NULL), setmref((pt)->varinfo, NULL) - -#endif - -/* Check if bytecode op returns. */ -static int bcopisret(BCOp op) -{ - switch (op) { - case BC_CALLMT: case BC_CALLT: - case BC_RETM: case BC_RET: case BC_RET0: case BC_RET1: - return 1; - default: - return 0; - } -} - -/* Fixup return instruction for prototype. */ -static void fs_fixup_ret(FuncState *fs) -{ - BCPos lastpc = fs->pc; - if (lastpc <= fs->lasttarget || !bcopisret(bc_op(fs->bcbase[lastpc-1].ins))) { - if ((fs->bl->flags & FSCOPE_UPVAL)) - bcemit_AJ(fs, BC_UCLO, 0, 0); - bcemit_AD(fs, BC_RET0, 0, 1); /* Need final return. */ - } - fs->bl->flags |= FSCOPE_NOCLOSE; /* Handled above. */ - fscope_end(fs); - lua_assert(fs->bl == NULL); - /* May need to fixup returns encoded before first function was created. */ - if (fs->flags & PROTO_FIXUP_RETURN) { - BCPos pc; - for (pc = 1; pc < lastpc; pc++) { - BCIns ins = fs->bcbase[pc].ins; - BCPos offset; - switch (bc_op(ins)) { - case BC_CALLMT: case BC_CALLT: - case BC_RETM: case BC_RET: case BC_RET0: case BC_RET1: - offset = bcemit_INS(fs, ins); /* Copy original instruction. */ - fs->bcbase[offset].line = fs->bcbase[pc].line; - offset = offset-(pc+1)+BCBIAS_J; - if (offset > BCMAX_D) - err_syntax(fs->ls, LJ_ERR_XFIXUP); - /* Replace with UCLO plus branch. */ - fs->bcbase[pc].ins = BCINS_AD(BC_UCLO, 0, offset); - break; - case BC_UCLO: - return; /* We're done. */ - default: - break; - } - } - } -} - -/* Finish a FuncState and return the new prototype. */ -static GCproto *fs_finish(LexState *ls, BCLine line) -{ - lua_State *L = ls->L; - FuncState *fs = ls->fs; - BCLine numline = line - fs->linedefined; - size_t sizept, ofsk, ofsuv, ofsli, ofsdbg, ofsvar; - GCproto *pt; - - /* Apply final fixups. */ - fs_fixup_ret(fs); - - /* Calculate total size of prototype including all colocated arrays. */ - sizept = sizeof(GCproto) + fs->pc*sizeof(BCIns) + fs->nkgc*sizeof(GCRef); - sizept = (sizept + sizeof(TValue)-1) & ~(sizeof(TValue)-1); - ofsk = sizept; sizept += fs->nkn*sizeof(TValue); - ofsuv = sizept; sizept += ((fs->nuv+1)&~1)*2; - ofsli = sizept; sizept += fs_prep_line(fs, numline); - ofsdbg = sizept; sizept += fs_prep_var(ls, fs, &ofsvar); - - /* Allocate prototype and initialize its fields. */ - pt = (GCproto *)lj_mem_newgco(L, (MSize)sizept); - pt->gct = ~LJ_TPROTO; - pt->sizept = (MSize)sizept; - pt->trace = 0; - pt->flags = (uint8_t)(fs->flags & ~(PROTO_HAS_RETURN|PROTO_FIXUP_RETURN)); - pt->numparams = fs->numparams; - pt->framesize = fs->framesize; - setgcref(pt->chunkname, obj2gco(ls->chunkname)); - - /* Close potentially uninitialized gap between bc and kgc. */ - *(uint32_t *)((char *)pt + ofsk - sizeof(GCRef)*(fs->nkgc+1)) = 0; - fs_fixup_bc(fs, pt, (BCIns *)((char *)pt + sizeof(GCproto)), fs->pc); - fs_fixup_k(fs, pt, (void *)((char *)pt + ofsk)); - fs_fixup_uv1(fs, pt, (uint16_t *)((char *)pt + ofsuv)); - fs_fixup_line(fs, pt, (void *)((char *)pt + ofsli), numline); - fs_fixup_var(ls, pt, (uint8_t *)((char *)pt + ofsdbg), ofsvar); - - lj_vmevent_send(L, BC, - setprotoV(L, L->top++, pt); - ); - - L->top--; /* Pop table of constants. */ - ls->vtop = fs->vbase; /* Reset variable stack. */ - ls->fs = fs->prev; - lua_assert(ls->fs != NULL || ls->tok == TK_eof); - return pt; -} - -/* Initialize a new FuncState. */ -static void fs_init(LexState *ls, FuncState *fs) -{ - lua_State *L = ls->L; - fs->prev = ls->fs; ls->fs = fs; /* Append to list. */ - fs->ls = ls; - fs->vbase = ls->vtop; - fs->L = L; - fs->pc = 0; - fs->lasttarget = 0; - fs->jpc = NO_JMP; - fs->freereg = 0; - fs->nkgc = 0; - fs->nkn = 0; - fs->nactvar = 0; - fs->nuv = 0; - fs->bl = NULL; - fs->flags = 0; - fs->framesize = 1; /* Minimum frame size. */ - fs->kt = lj_tab_new(L, 0, 0); - /* Anchor table of constants in stack to avoid being collected. */ - settabV(L, L->top, fs->kt); - incr_top(L); -} - -/* -- Expressions --------------------------------------------------------- */ - -/* Forward declaration. */ -static void expr(LexState *ls, ExpDesc *v); - -/* Return string expression. */ -static void expr_str(LexState *ls, ExpDesc *e) -{ - expr_init(e, VKSTR, 0); - e->u.sval = lex_str(ls); -} - -/* Return index expression. */ -static void expr_index(FuncState *fs, ExpDesc *t, ExpDesc *e) -{ - /* Already called: expr_toval(fs, e). */ - t->k = VINDEXED; - if (expr_isnumk(e)) { -#if LJ_DUALNUM - if (tvisint(expr_numtv(e))) { - int32_t k = intV(expr_numtv(e)); - if (checku8(k)) { - t->u.s.aux = BCMAX_C+1+(uint32_t)k; /* 256..511: const byte key */ - return; - } - } -#else - lua_Number n = expr_numberV(e); - int32_t k = lj_num2int(n); - if (checku8(k) && n == (lua_Number)k) { - t->u.s.aux = BCMAX_C+1+(uint32_t)k; /* 256..511: const byte key */ - return; - } -#endif - } else if (expr_isstrk(e)) { - BCReg idx = const_str(fs, e); - if (idx <= BCMAX_C) { - t->u.s.aux = ~idx; /* -256..-1: const string key */ - return; - } - } - t->u.s.aux = expr_toanyreg(fs, e); /* 0..255: register */ -} - -/* Parse index expression with named field. */ -static void expr_field(LexState *ls, ExpDesc *v) -{ - FuncState *fs = ls->fs; - ExpDesc key; - expr_toanyreg(fs, v); - lj_lex_next(ls); /* Skip dot or colon. */ - expr_str(ls, &key); - expr_index(fs, v, &key); -} - -/* Parse index expression with brackets. */ -static void expr_bracket(LexState *ls, ExpDesc *v) -{ - lj_lex_next(ls); /* Skip '['. */ - expr(ls, v); - expr_toval(ls->fs, v); - lex_check(ls, ']'); -} - -/* Get value of constant expression. */ -static void expr_kvalue(TValue *v, ExpDesc *e) -{ - if (e->k <= VKTRUE) { - setpriV(v, ~(uint32_t)e->k); - } else if (e->k == VKSTR) { - setgcVraw(v, obj2gco(e->u.sval), LJ_TSTR); - } else { - lua_assert(tvisnumber(expr_numtv(e))); - *v = *expr_numtv(e); - } -} - -/* Parse table constructor expression. */ -static void expr_table(LexState *ls, ExpDesc *e) -{ - FuncState *fs = ls->fs; - BCLine line = ls->linenumber; - GCtab *t = NULL; - int vcall = 0, needarr = 0, fixt = 0; - uint32_t narr = 1; /* First array index. */ - uint32_t nhash = 0; /* Number of hash entries. */ - BCReg freg = fs->freereg; - BCPos pc = bcemit_AD(fs, BC_TNEW, freg, 0); - expr_init(e, VNONRELOC, freg); - bcreg_reserve(fs, 1); - freg++; - lex_check(ls, '{'); - while (ls->tok != '}') { - ExpDesc key, val; - vcall = 0; - if (ls->tok == '[') { - expr_bracket(ls, &key); /* Already calls expr_toval. */ - if (!expr_isk(&key)) expr_index(fs, e, &key); - if (expr_isnumk(&key) && expr_numiszero(&key)) needarr = 1; else nhash++; - lex_check(ls, '='); - } else if ((ls->tok == TK_name || (!LJ_52 && ls->tok == TK_goto)) && - lj_lex_lookahead(ls) == '=') { - expr_str(ls, &key); - lex_check(ls, '='); - nhash++; - } else { - expr_init(&key, VKNUM, 0); - setintV(&key.u.nval, (int)narr); - narr++; - needarr = vcall = 1; - } - expr(ls, &val); - if (expr_isk(&key) && key.k != VKNIL && - (key.k == VKSTR || expr_isk_nojump(&val))) { - TValue k, *v; - if (!t) { /* Create template table on demand. */ - BCReg kidx; - t = lj_tab_new(fs->L, needarr ? narr : 0, hsize2hbits(nhash)); - kidx = const_gc(fs, obj2gco(t), LJ_TTAB); - fs->bcbase[pc].ins = BCINS_AD(BC_TDUP, freg-1, kidx); - } - vcall = 0; - expr_kvalue(&k, &key); - v = lj_tab_set(fs->L, t, &k); - lj_gc_anybarriert(fs->L, t); - if (expr_isk_nojump(&val)) { /* Add const key/value to template table. */ - expr_kvalue(v, &val); - } else { /* Otherwise create dummy string key (avoids lj_tab_newkey). */ - settabV(fs->L, v, t); /* Preserve key with table itself as value. */ - fixt = 1; /* Fix this later, after all resizes. */ - goto nonconst; - } - } else { - nonconst: - if (val.k != VCALL) { expr_toanyreg(fs, &val); vcall = 0; } - if (expr_isk(&key)) expr_index(fs, e, &key); - bcemit_store(fs, e, &val); - } - fs->freereg = freg; - if (!lex_opt(ls, ',') && !lex_opt(ls, ';')) break; - } - lex_match(ls, '}', '{', line); - if (vcall) { - BCInsLine *ilp = &fs->bcbase[fs->pc-1]; - ExpDesc en; - lua_assert(bc_a(ilp->ins) == freg && - bc_op(ilp->ins) == (narr > 256 ? BC_TSETV : BC_TSETB)); - expr_init(&en, VKNUM, 0); - en.u.nval.u32.lo = narr-1; - en.u.nval.u32.hi = 0x43300000; /* Biased integer to avoid denormals. */ - if (narr > 256) { fs->pc--; ilp--; } - ilp->ins = BCINS_AD(BC_TSETM, freg, const_num(fs, &en)); - setbc_b(&ilp[-1].ins, 0); - } - if (pc == fs->pc-1) { /* Make expr relocable if possible. */ - e->u.s.info = pc; - fs->freereg--; - e->k = VRELOCABLE; - } else { - e->k = VNONRELOC; /* May have been changed by expr_index. */ - } - if (!t) { /* Construct TNEW RD: hhhhhaaaaaaaaaaa. */ - BCIns *ip = &fs->bcbase[pc].ins; - if (!needarr) narr = 0; - else if (narr < 3) narr = 3; - else if (narr > 0x7ff) narr = 0x7ff; - setbc_d(ip, narr|(hsize2hbits(nhash)<<11)); - } else { - if (needarr && t->asize < narr) - lj_tab_reasize(fs->L, t, narr-1); - if (fixt) { /* Fix value for dummy keys in template table. */ - Node *node = noderef(t->node); - uint32_t i, hmask = t->hmask; - for (i = 0; i <= hmask; i++) { - Node *n = &node[i]; - if (tvistab(&n->val)) { - lua_assert(tabV(&n->val) == t); - setnilV(&n->val); /* Turn value into nil. */ - } - } - } - lj_gc_check(fs->L); - } -} - -/* Parse function parameters. */ -static BCReg parse_params(LexState *ls, int needself) -{ - FuncState *fs = ls->fs; - BCReg nparams = 0; - lex_check(ls, '('); - if (needself) - var_new_lit(ls, nparams++, "self"); - if (ls->tok != ')') { - do { - if (ls->tok == TK_name || (!LJ_52 && ls->tok == TK_goto)) { - var_new(ls, nparams++, lex_str(ls)); - } else if (ls->tok == TK_dots) { - lj_lex_next(ls); - fs->flags |= PROTO_VARARG; - break; - } else { - err_syntax(ls, LJ_ERR_XPARAM); - } - } while (lex_opt(ls, ',')); - } - var_add(ls, nparams); - lua_assert(fs->nactvar == nparams); - bcreg_reserve(fs, nparams); - lex_check(ls, ')'); - return nparams; -} - -/* Forward declaration. */ -static void parse_chunk(LexState *ls); - -/* Parse body of a function. */ -static void parse_body(LexState *ls, ExpDesc *e, int needself, BCLine line) -{ - FuncState fs, *pfs = ls->fs; - FuncScope bl; - GCproto *pt; - ptrdiff_t oldbase = pfs->bcbase - ls->bcstack; - fs_init(ls, &fs); - fscope_begin(&fs, &bl, 0); - fs.linedefined = line; - fs.numparams = (uint8_t)parse_params(ls, needself); - fs.bcbase = pfs->bcbase + pfs->pc; - fs.bclim = pfs->bclim - pfs->pc; - bcemit_AD(&fs, BC_FUNCF, 0, 0); /* Placeholder. */ - parse_chunk(ls); - if (ls->tok != TK_end) lex_match(ls, TK_end, TK_function, line); - pt = fs_finish(ls, (ls->lastline = ls->linenumber)); - pfs->bcbase = ls->bcstack + oldbase; /* May have been reallocated. */ - pfs->bclim = (BCPos)(ls->sizebcstack - oldbase); - /* Store new prototype in the constant array of the parent. */ - expr_init(e, VRELOCABLE, - bcemit_AD(pfs, BC_FNEW, 0, const_gc(pfs, obj2gco(pt), LJ_TPROTO))); -#if LJ_HASFFI - pfs->flags |= (fs.flags & PROTO_FFI); -#endif - if (!(pfs->flags & PROTO_CHILD)) { - if (pfs->flags & PROTO_HAS_RETURN) - pfs->flags |= PROTO_FIXUP_RETURN; - pfs->flags |= PROTO_CHILD; - } - lj_lex_next(ls); -} - -/* Parse expression list. Last expression is left open. */ -static BCReg expr_list(LexState *ls, ExpDesc *v) -{ - BCReg n = 1; - expr(ls, v); - while (lex_opt(ls, ',')) { - expr_tonextreg(ls->fs, v); - expr(ls, v); - n++; - } - return n; -} - -/* Parse function argument list. */ -static void parse_args(LexState *ls, ExpDesc *e) -{ - FuncState *fs = ls->fs; - ExpDesc args; - BCIns ins; - BCReg base; - BCLine line = ls->linenumber; - if (ls->tok == '(') { -#if !LJ_52 - if (line != ls->lastline) - err_syntax(ls, LJ_ERR_XAMBIG); -#endif - lj_lex_next(ls); - if (ls->tok == ')') { /* f(). */ - args.k = VVOID; - } else { - expr_list(ls, &args); - if (args.k == VCALL) /* f(a, b, g()) or f(a, b, ...). */ - setbc_b(bcptr(fs, &args), 0); /* Pass on multiple results. */ - } - lex_match(ls, ')', '(', line); - } else if (ls->tok == '{') { - expr_table(ls, &args); - } else if (ls->tok == TK_string) { - expr_init(&args, VKSTR, 0); - args.u.sval = strV(&ls->tokval); - lj_lex_next(ls); - } else { - err_syntax(ls, LJ_ERR_XFUNARG); - return; /* Silence compiler. */ - } - lua_assert(e->k == VNONRELOC); - base = e->u.s.info; /* Base register for call. */ - if (args.k == VCALL) { - ins = BCINS_ABC(BC_CALLM, base, 2, args.u.s.aux - base - 1 - LJ_FR2); - } else { - if (args.k != VVOID) - expr_tonextreg(fs, &args); - ins = BCINS_ABC(BC_CALL, base, 2, fs->freereg - base - LJ_FR2); - } - expr_init(e, VCALL, bcemit_INS(fs, ins)); - e->u.s.aux = base; - fs->bcbase[fs->pc - 1].line = line; - fs->freereg = base+1; /* Leave one result by default. */ -} - -/* Parse primary expression. */ -static void expr_primary(LexState *ls, ExpDesc *v) -{ - FuncState *fs = ls->fs; - /* Parse prefix expression. */ - if (ls->tok == '(') { - BCLine line = ls->linenumber; - lj_lex_next(ls); - expr(ls, v); - lex_match(ls, ')', '(', line); - expr_discharge(ls->fs, v); - } else if (ls->tok == TK_name || (!LJ_52 && ls->tok == TK_goto)) { - var_lookup(ls, v); - } else { - err_syntax(ls, LJ_ERR_XSYMBOL); - } - for (;;) { /* Parse multiple expression suffixes. */ - if (ls->tok == '.') { - expr_field(ls, v); - } else if (ls->tok == '[') { - ExpDesc key; - expr_toanyreg(fs, v); - expr_bracket(ls, &key); - expr_index(fs, v, &key); - } else if (ls->tok == ':') { - ExpDesc key; - lj_lex_next(ls); - expr_str(ls, &key); - bcemit_method(fs, v, &key); - parse_args(ls, v); - } else if (ls->tok == '(' || ls->tok == TK_string || ls->tok == '{') { - expr_tonextreg(fs, v); - if (LJ_FR2) bcreg_reserve(fs, 1); - parse_args(ls, v); - } else { - break; - } - } -} - -/* Parse simple expression. */ -static void expr_simple(LexState *ls, ExpDesc *v) -{ - switch (ls->tok) { - case TK_number: - expr_init(v, (LJ_HASFFI && tviscdata(&ls->tokval)) ? VKCDATA : VKNUM, 0); - copyTV(ls->L, &v->u.nval, &ls->tokval); - break; - case TK_string: - expr_init(v, VKSTR, 0); - v->u.sval = strV(&ls->tokval); - break; - case TK_nil: - expr_init(v, VKNIL, 0); - break; - case TK_true: - expr_init(v, VKTRUE, 0); - break; - case TK_false: - expr_init(v, VKFALSE, 0); - break; - case TK_dots: { /* Vararg. */ - FuncState *fs = ls->fs; - BCReg base; - checkcond(ls, fs->flags & PROTO_VARARG, LJ_ERR_XDOTS); - bcreg_reserve(fs, 1); - base = fs->freereg-1; - expr_init(v, VCALL, bcemit_ABC(fs, BC_VARG, base, 2, fs->numparams)); - v->u.s.aux = base; - break; - } - case '{': /* Table constructor. */ - expr_table(ls, v); - return; - case TK_function: - lj_lex_next(ls); - parse_body(ls, v, 0, ls->linenumber); - return; - default: - expr_primary(ls, v); - return; - } - lj_lex_next(ls); -} - -/* Manage syntactic levels to avoid blowing up the stack. */ -static void synlevel_begin(LexState *ls) -{ - if (++ls->level >= LJ_MAX_XLEVEL) - lj_lex_error(ls, 0, LJ_ERR_XLEVELS); -} - -#define synlevel_end(ls) ((ls)->level--) - -/* Convert token to binary operator. */ -static BinOpr token2binop(LexToken tok) -{ - switch (tok) { - case '+': return OPR_ADD; - case '-': return OPR_SUB; - case '*': return OPR_MUL; - case '/': return OPR_DIV; - case '%': return OPR_MOD; - case '^': return OPR_POW; - case TK_concat: return OPR_CONCAT; - case TK_ne: return OPR_NE; - case TK_eq: return OPR_EQ; - case '<': return OPR_LT; - case TK_le: return OPR_LE; - case '>': return OPR_GT; - case TK_ge: return OPR_GE; - case TK_and: return OPR_AND; - case TK_or: return OPR_OR; - default: return OPR_NOBINOPR; - } -} - -/* Priorities for each binary operator. ORDER OPR. */ -static const struct { - uint8_t left; /* Left priority. */ - uint8_t right; /* Right priority. */ -} priority[] = { - {6,6}, {6,6}, {7,7}, {7,7}, {7,7}, /* ADD SUB MUL DIV MOD */ - {10,9}, {5,4}, /* POW CONCAT (right associative) */ - {3,3}, {3,3}, /* EQ NE */ - {3,3}, {3,3}, {3,3}, {3,3}, /* LT GE GT LE */ - {2,2}, {1,1} /* AND OR */ -}; - -#define UNARY_PRIORITY 8 /* Priority for unary operators. */ - -/* Forward declaration. */ -static BinOpr expr_binop(LexState *ls, ExpDesc *v, uint32_t limit); - -/* Parse unary expression. */ -static void expr_unop(LexState *ls, ExpDesc *v) -{ - BCOp op; - if (ls->tok == TK_not) { - op = BC_NOT; - } else if (ls->tok == '-') { - op = BC_UNM; - } else if (ls->tok == '#') { - op = BC_LEN; - } else { - expr_simple(ls, v); - return; - } - lj_lex_next(ls); - expr_binop(ls, v, UNARY_PRIORITY); - bcemit_unop(ls->fs, op, v); -} - -/* Parse binary expressions with priority higher than the limit. */ -static BinOpr expr_binop(LexState *ls, ExpDesc *v, uint32_t limit) -{ - BinOpr op; - synlevel_begin(ls); - expr_unop(ls, v); - op = token2binop(ls->tok); - while (op != OPR_NOBINOPR && priority[op].left > limit) { - ExpDesc v2; - BinOpr nextop; - lj_lex_next(ls); - bcemit_binop_left(ls->fs, op, v); - /* Parse binary expression with higher priority. */ - nextop = expr_binop(ls, &v2, priority[op].right); - bcemit_binop(ls->fs, op, v, &v2); - op = nextop; - } - synlevel_end(ls); - return op; /* Return unconsumed binary operator (if any). */ -} - -/* Parse expression. */ -static void expr(LexState *ls, ExpDesc *v) -{ - expr_binop(ls, v, 0); /* Priority 0: parse whole expression. */ -} - -/* Assign expression to the next register. */ -static void expr_next(LexState *ls) -{ - ExpDesc e; - expr(ls, &e); - expr_tonextreg(ls->fs, &e); -} - -/* Parse conditional expression. */ -static BCPos expr_cond(LexState *ls) -{ - ExpDesc v; - expr(ls, &v); - if (v.k == VKNIL) v.k = VKFALSE; - bcemit_branch_t(ls->fs, &v); - return v.f; -} - -/* -- Assignments --------------------------------------------------------- */ - -/* List of LHS variables. */ -typedef struct LHSVarList { - ExpDesc v; /* LHS variable. */ - struct LHSVarList *prev; /* Link to previous LHS variable. */ -} LHSVarList; - -/* Eliminate write-after-read hazards for local variable assignment. */ -static void assign_hazard(LexState *ls, LHSVarList *lh, const ExpDesc *v) -{ - FuncState *fs = ls->fs; - BCReg reg = v->u.s.info; /* Check against this variable. */ - BCReg tmp = fs->freereg; /* Rename to this temp. register (if needed). */ - int hazard = 0; - for (; lh; lh = lh->prev) { - if (lh->v.k == VINDEXED) { - if (lh->v.u.s.info == reg) { /* t[i], t = 1, 2 */ - hazard = 1; - lh->v.u.s.info = tmp; - } - if (lh->v.u.s.aux == reg) { /* t[i], i = 1, 2 */ - hazard = 1; - lh->v.u.s.aux = tmp; - } - } - } - if (hazard) { - bcemit_AD(fs, BC_MOV, tmp, reg); /* Rename conflicting variable. */ - bcreg_reserve(fs, 1); - } -} - -/* Adjust LHS/RHS of an assignment. */ -static void assign_adjust(LexState *ls, BCReg nvars, BCReg nexps, ExpDesc *e) -{ - FuncState *fs = ls->fs; - int32_t extra = (int32_t)nvars - (int32_t)nexps; - if (e->k == VCALL) { - extra++; /* Compensate for the VCALL itself. */ - if (extra < 0) extra = 0; - setbc_b(bcptr(fs, e), extra+1); /* Fixup call results. */ - if (extra > 1) bcreg_reserve(fs, (BCReg)extra-1); - } else { - if (e->k != VVOID) - expr_tonextreg(fs, e); /* Close last expression. */ - if (extra > 0) { /* Leftover LHS are set to nil. */ - BCReg reg = fs->freereg; - bcreg_reserve(fs, (BCReg)extra); - bcemit_nil(fs, reg, (BCReg)extra); - } - } - if (nexps > nvars) - ls->fs->freereg -= nexps - nvars; /* Drop leftover regs. */ -} - -/* Recursively parse assignment statement. */ -static void parse_assignment(LexState *ls, LHSVarList *lh, BCReg nvars) -{ - ExpDesc e; - checkcond(ls, VLOCAL <= lh->v.k && lh->v.k <= VINDEXED, LJ_ERR_XSYNTAX); - if (lex_opt(ls, ',')) { /* Collect LHS list and recurse upwards. */ - LHSVarList vl; - vl.prev = lh; - expr_primary(ls, &vl.v); - if (vl.v.k == VLOCAL) - assign_hazard(ls, lh, &vl.v); - checklimit(ls->fs, ls->level + nvars, LJ_MAX_XLEVEL, "variable names"); - parse_assignment(ls, &vl, nvars+1); - } else { /* Parse RHS. */ - BCReg nexps; - lex_check(ls, '='); - nexps = expr_list(ls, &e); - if (nexps == nvars) { - if (e.k == VCALL) { - if (bc_op(*bcptr(ls->fs, &e)) == BC_VARG) { /* Vararg assignment. */ - ls->fs->freereg--; - e.k = VRELOCABLE; - } else { /* Multiple call results. */ - e.u.s.info = e.u.s.aux; /* Base of call is not relocatable. */ - e.k = VNONRELOC; - } - } - bcemit_store(ls->fs, &lh->v, &e); - return; - } - assign_adjust(ls, nvars, nexps, &e); - } - /* Assign RHS to LHS and recurse downwards. */ - expr_init(&e, VNONRELOC, ls->fs->freereg-1); - bcemit_store(ls->fs, &lh->v, &e); -} - -/* Parse call statement or assignment. */ -static void parse_call_assign(LexState *ls) -{ - FuncState *fs = ls->fs; - LHSVarList vl; - expr_primary(ls, &vl.v); - if (vl.v.k == VCALL) { /* Function call statement. */ - setbc_b(bcptr(fs, &vl.v), 1); /* No results. */ - } else { /* Start of an assignment. */ - vl.prev = NULL; - parse_assignment(ls, &vl, 1); - } -} - -/* Parse 'local' statement. */ -static void parse_local(LexState *ls) -{ - if (lex_opt(ls, TK_function)) { /* Local function declaration. */ - ExpDesc v, b; - FuncState *fs = ls->fs; - var_new(ls, 0, lex_str(ls)); - expr_init(&v, VLOCAL, fs->freereg); - v.u.s.aux = fs->varmap[fs->freereg]; - bcreg_reserve(fs, 1); - var_add(ls, 1); - parse_body(ls, &b, 0, ls->linenumber); - /* bcemit_store(fs, &v, &b) without setting VSTACK_VAR_RW. */ - expr_free(fs, &b); - expr_toreg(fs, &b, v.u.s.info); - /* The upvalue is in scope, but the local is only valid after the store. */ - var_get(ls, fs, fs->nactvar - 1).startpc = fs->pc; - } else { /* Local variable declaration. */ - ExpDesc e; - BCReg nexps, nvars = 0; - do { /* Collect LHS. */ - var_new(ls, nvars++, lex_str(ls)); - } while (lex_opt(ls, ',')); - if (lex_opt(ls, '=')) { /* Optional RHS. */ - nexps = expr_list(ls, &e); - } else { /* Or implicitly set to nil. */ - e.k = VVOID; - nexps = 0; - } - assign_adjust(ls, nvars, nexps, &e); - var_add(ls, nvars); - } -} - -/* Parse 'function' statement. */ -static void parse_func(LexState *ls, BCLine line) -{ - FuncState *fs; - ExpDesc v, b; - int needself = 0; - lj_lex_next(ls); /* Skip 'function'. */ - /* Parse function name. */ - var_lookup(ls, &v); - while (ls->tok == '.') /* Multiple dot-separated fields. */ - expr_field(ls, &v); - if (ls->tok == ':') { /* Optional colon to signify method call. */ - needself = 1; - expr_field(ls, &v); - } - parse_body(ls, &b, needself, line); - fs = ls->fs; - bcemit_store(fs, &v, &b); - fs->bcbase[fs->pc - 1].line = line; /* Set line for the store. */ -} - -/* -- Control transfer statements ----------------------------------------- */ - -/* Check for end of block. */ -static int parse_isend(LexToken tok) -{ - switch (tok) { - case TK_else: case TK_elseif: case TK_end: case TK_until: case TK_eof: - return 1; - default: - return 0; - } -} - -/* Parse 'return' statement. */ -static void parse_return(LexState *ls) -{ - BCIns ins; - FuncState *fs = ls->fs; - lj_lex_next(ls); /* Skip 'return'. */ - fs->flags |= PROTO_HAS_RETURN; - if (parse_isend(ls->tok) || ls->tok == ';') { /* Bare return. */ - ins = BCINS_AD(BC_RET0, 0, 1); - } else { /* Return with one or more values. */ - ExpDesc e; /* Receives the _last_ expression in the list. */ - BCReg nret = expr_list(ls, &e); - if (nret == 1) { /* Return one result. */ - if (e.k == VCALL) { /* Check for tail call. */ - BCIns *ip = bcptr(fs, &e); - /* It doesn't pay off to add BC_VARGT just for 'return ...'. */ - if (bc_op(*ip) == BC_VARG) goto notailcall; - fs->pc--; - ins = BCINS_AD(bc_op(*ip)-BC_CALL+BC_CALLT, bc_a(*ip), bc_c(*ip)); - } else { /* Can return the result from any register. */ - ins = BCINS_AD(BC_RET1, expr_toanyreg(fs, &e), 2); - } - } else { - if (e.k == VCALL) { /* Append all results from a call. */ - notailcall: - setbc_b(bcptr(fs, &e), 0); - ins = BCINS_AD(BC_RETM, fs->nactvar, e.u.s.aux - fs->nactvar); - } else { - expr_tonextreg(fs, &e); /* Force contiguous registers. */ - ins = BCINS_AD(BC_RET, fs->nactvar, nret+1); - } - } - } - if (fs->flags & PROTO_CHILD) - bcemit_AJ(fs, BC_UCLO, 0, 0); /* May need to close upvalues first. */ - bcemit_INS(fs, ins); -} - -/* Parse 'break' statement. */ -static void parse_break(LexState *ls) -{ - ls->fs->bl->flags |= FSCOPE_BREAK; - gola_new(ls, NAME_BREAK, VSTACK_GOTO, bcemit_jmp(ls->fs)); -} - -/* Parse 'goto' statement. */ -static void parse_goto(LexState *ls) -{ - FuncState *fs = ls->fs; - GCstr *name = lex_str(ls); - VarInfo *vl = gola_findlabel(ls, name); - if (vl) /* Treat backwards goto within same scope like a loop. */ - bcemit_AJ(fs, BC_LOOP, vl->slot, -1); /* No BC range check. */ - fs->bl->flags |= FSCOPE_GOLA; - gola_new(ls, name, VSTACK_GOTO, bcemit_jmp(fs)); -} - -/* Parse label. */ -static void parse_label(LexState *ls) -{ - FuncState *fs = ls->fs; - GCstr *name; - MSize idx; - fs->lasttarget = fs->pc; - fs->bl->flags |= FSCOPE_GOLA; - lj_lex_next(ls); /* Skip '::'. */ - name = lex_str(ls); - if (gola_findlabel(ls, name)) - lj_lex_error(ls, 0, LJ_ERR_XLDUP, strdata(name)); - idx = gola_new(ls, name, VSTACK_LABEL, fs->pc); - lex_check(ls, TK_label); - /* Recursively parse trailing statements: labels and ';' (Lua 5.2 only). */ - for (;;) { - if (ls->tok == TK_label) { - synlevel_begin(ls); - parse_label(ls); - synlevel_end(ls); - } else if (LJ_52 && ls->tok == ';') { - lj_lex_next(ls); - } else { - break; - } - } - /* Trailing label is considered to be outside of scope. */ - if (parse_isend(ls->tok) && ls->tok != TK_until) - ls->vstack[idx].slot = fs->bl->nactvar; - gola_resolve(ls, fs->bl, idx); -} - -/* -- Blocks, loops and conditional statements ---------------------------- */ - -/* Parse a block. */ -static void parse_block(LexState *ls) -{ - FuncState *fs = ls->fs; - FuncScope bl; - fscope_begin(fs, &bl, 0); - parse_chunk(ls); - fscope_end(fs); -} - -/* Parse 'while' statement. */ -static void parse_while(LexState *ls, BCLine line) -{ - FuncState *fs = ls->fs; - BCPos start, loop, condexit; - FuncScope bl; - lj_lex_next(ls); /* Skip 'while'. */ - start = fs->lasttarget = fs->pc; - condexit = expr_cond(ls); - fscope_begin(fs, &bl, FSCOPE_LOOP); - lex_check(ls, TK_do); - loop = bcemit_AD(fs, BC_LOOP, fs->nactvar, 0); - parse_block(ls); - jmp_patch(fs, bcemit_jmp(fs), start); - lex_match(ls, TK_end, TK_while, line); - fscope_end(fs); - jmp_tohere(fs, condexit); - jmp_patchins(fs, loop, fs->pc); -} - -/* Parse 'repeat' statement. */ -static void parse_repeat(LexState *ls, BCLine line) -{ - FuncState *fs = ls->fs; - BCPos loop = fs->lasttarget = fs->pc; - BCPos condexit; - FuncScope bl1, bl2; - fscope_begin(fs, &bl1, FSCOPE_LOOP); /* Breakable loop scope. */ - fscope_begin(fs, &bl2, 0); /* Inner scope. */ - lj_lex_next(ls); /* Skip 'repeat'. */ - bcemit_AD(fs, BC_LOOP, fs->nactvar, 0); - parse_chunk(ls); - lex_match(ls, TK_until, TK_repeat, line); - condexit = expr_cond(ls); /* Parse condition (still inside inner scope). */ - if (!(bl2.flags & FSCOPE_UPVAL)) { /* No upvalues? Just end inner scope. */ - fscope_end(fs); - } else { /* Otherwise generate: cond: UCLO+JMP out, !cond: UCLO+JMP loop. */ - parse_break(ls); /* Break from loop and close upvalues. */ - jmp_tohere(fs, condexit); - fscope_end(fs); /* End inner scope and close upvalues. */ - condexit = bcemit_jmp(fs); - } - jmp_patch(fs, condexit, loop); /* Jump backwards if !cond. */ - jmp_patchins(fs, loop, fs->pc); - fscope_end(fs); /* End loop scope. */ -} - -/* Parse numeric 'for'. */ -static void parse_for_num(LexState *ls, GCstr *varname, BCLine line) -{ - FuncState *fs = ls->fs; - BCReg base = fs->freereg; - FuncScope bl; - BCPos loop, loopend; - /* Hidden control variables. */ - var_new_fixed(ls, FORL_IDX, VARNAME_FOR_IDX); - var_new_fixed(ls, FORL_STOP, VARNAME_FOR_STOP); - var_new_fixed(ls, FORL_STEP, VARNAME_FOR_STEP); - /* Visible copy of index variable. */ - var_new(ls, FORL_EXT, varname); - lex_check(ls, '='); - expr_next(ls); - lex_check(ls, ','); - expr_next(ls); - if (lex_opt(ls, ',')) { - expr_next(ls); - } else { - bcemit_AD(fs, BC_KSHORT, fs->freereg, 1); /* Default step is 1. */ - bcreg_reserve(fs, 1); - } - var_add(ls, 3); /* Hidden control variables. */ - lex_check(ls, TK_do); - loop = bcemit_AJ(fs, BC_FORI, base, NO_JMP); - fscope_begin(fs, &bl, 0); /* Scope for visible variables. */ - var_add(ls, 1); - bcreg_reserve(fs, 1); - parse_block(ls); - fscope_end(fs); - /* Perform loop inversion. Loop control instructions are at the end. */ - loopend = bcemit_AJ(fs, BC_FORL, base, NO_JMP); - fs->bcbase[loopend].line = line; /* Fix line for control ins. */ - jmp_patchins(fs, loopend, loop+1); - jmp_patchins(fs, loop, fs->pc); -} - -/* Try to predict whether the iterator is next() and specialize the bytecode. -** Detecting next() and pairs() by name is simplistic, but quite effective. -** The interpreter backs off if the check for the closure fails at runtime. -*/ -static int predict_next(LexState *ls, FuncState *fs, BCPos pc) -{ - BCIns ins = fs->bcbase[pc].ins; - GCstr *name; - cTValue *o; - switch (bc_op(ins)) { - case BC_MOV: - name = gco2str(gcref(var_get(ls, fs, bc_d(ins)).name)); - break; - case BC_UGET: - name = gco2str(gcref(ls->vstack[fs->uvmap[bc_d(ins)]].name)); - break; - case BC_GGET: - /* There's no inverse index (yet), so lookup the strings. */ - o = lj_tab_getstr(fs->kt, lj_str_newlit(ls->L, "pairs")); - if (o && tvhaskslot(o) && tvkslot(o) == bc_d(ins)) - return 1; - o = lj_tab_getstr(fs->kt, lj_str_newlit(ls->L, "next")); - if (o && tvhaskslot(o) && tvkslot(o) == bc_d(ins)) - return 1; - return 0; - default: - return 0; - } - return (name->len == 5 && !strcmp(strdata(name), "pairs")) || - (name->len == 4 && !strcmp(strdata(name), "next")); -} - -/* Parse 'for' iterator. */ -static void parse_for_iter(LexState *ls, GCstr *indexname) -{ - FuncState *fs = ls->fs; - ExpDesc e; - BCReg nvars = 0; - BCLine line; - BCReg base = fs->freereg + 3; - BCPos loop, loopend, exprpc = fs->pc; - FuncScope bl; - int isnext; - /* Hidden control variables. */ - var_new_fixed(ls, nvars++, VARNAME_FOR_GEN); - var_new_fixed(ls, nvars++, VARNAME_FOR_STATE); - var_new_fixed(ls, nvars++, VARNAME_FOR_CTL); - /* Visible variables returned from iterator. */ - var_new(ls, nvars++, indexname); - while (lex_opt(ls, ',')) - var_new(ls, nvars++, lex_str(ls)); - lex_check(ls, TK_in); - line = ls->linenumber; - assign_adjust(ls, 3, expr_list(ls, &e), &e); - /* The iterator needs another 3 [4] slots (func [pc] | state ctl). */ - bcreg_bump(fs, 3+LJ_FR2); - isnext = (nvars <= 5 && predict_next(ls, fs, exprpc)); - var_add(ls, 3); /* Hidden control variables. */ - lex_check(ls, TK_do); - loop = bcemit_AJ(fs, isnext ? BC_ISNEXT : BC_JMP, base, NO_JMP); - fscope_begin(fs, &bl, 0); /* Scope for visible variables. */ - var_add(ls, nvars-3); - bcreg_reserve(fs, nvars-3); - parse_block(ls); - fscope_end(fs); - /* Perform loop inversion. Loop control instructions are at the end. */ - jmp_patchins(fs, loop, fs->pc); - bcemit_ABC(fs, isnext ? BC_ITERN : BC_ITERC, base, nvars-3+1, 2+1); - loopend = bcemit_AJ(fs, BC_ITERL, base, NO_JMP); - fs->bcbase[loopend-1].line = line; /* Fix line for control ins. */ - fs->bcbase[loopend].line = line; - jmp_patchins(fs, loopend, loop+1); -} - -/* Parse 'for' statement. */ -static void parse_for(LexState *ls, BCLine line) -{ - FuncState *fs = ls->fs; - GCstr *varname; - FuncScope bl; - fscope_begin(fs, &bl, FSCOPE_LOOP); - lj_lex_next(ls); /* Skip 'for'. */ - varname = lex_str(ls); /* Get first variable name. */ - if (ls->tok == '=') - parse_for_num(ls, varname, line); - else if (ls->tok == ',' || ls->tok == TK_in) - parse_for_iter(ls, varname); - else - err_syntax(ls, LJ_ERR_XFOR); - lex_match(ls, TK_end, TK_for, line); - fscope_end(fs); /* Resolve break list. */ -} - -/* Parse condition and 'then' block. */ -static BCPos parse_then(LexState *ls) -{ - BCPos condexit; - lj_lex_next(ls); /* Skip 'if' or 'elseif'. */ - condexit = expr_cond(ls); - lex_check(ls, TK_then); - parse_block(ls); - return condexit; -} - -/* Parse 'if' statement. */ -static void parse_if(LexState *ls, BCLine line) -{ - FuncState *fs = ls->fs; - BCPos flist; - BCPos escapelist = NO_JMP; - flist = parse_then(ls); - while (ls->tok == TK_elseif) { /* Parse multiple 'elseif' blocks. */ - jmp_append(fs, &escapelist, bcemit_jmp(fs)); - jmp_tohere(fs, flist); - flist = parse_then(ls); - } - if (ls->tok == TK_else) { /* Parse optional 'else' block. */ - jmp_append(fs, &escapelist, bcemit_jmp(fs)); - jmp_tohere(fs, flist); - lj_lex_next(ls); /* Skip 'else'. */ - parse_block(ls); - } else { - jmp_append(fs, &escapelist, flist); - } - jmp_tohere(fs, escapelist); - lex_match(ls, TK_end, TK_if, line); -} - -/* -- Parse statements ---------------------------------------------------- */ - -/* Parse a statement. Returns 1 if it must be the last one in a chunk. */ -static int parse_stmt(LexState *ls) -{ - BCLine line = ls->linenumber; - switch (ls->tok) { - case TK_if: - parse_if(ls, line); - break; - case TK_while: - parse_while(ls, line); - break; - case TK_do: - lj_lex_next(ls); - parse_block(ls); - lex_match(ls, TK_end, TK_do, line); - break; - case TK_for: - parse_for(ls, line); - break; - case TK_repeat: - parse_repeat(ls, line); - break; - case TK_function: - parse_func(ls, line); - break; - case TK_local: - lj_lex_next(ls); - parse_local(ls); - break; - case TK_return: - parse_return(ls); - return 1; /* Must be last. */ - case TK_break: - lj_lex_next(ls); - parse_break(ls); - return !LJ_52; /* Must be last in Lua 5.1. */ -#if LJ_52 - case ';': - lj_lex_next(ls); - break; -#endif - case TK_label: - parse_label(ls); - break; - case TK_goto: - if (LJ_52 || lj_lex_lookahead(ls) == TK_name) { - lj_lex_next(ls); - parse_goto(ls); - break; - } - /* fallthrough */ - default: - parse_call_assign(ls); - break; - } - return 0; -} - -/* A chunk is a list of statements optionally separated by semicolons. */ -static void parse_chunk(LexState *ls) -{ - int islast = 0; - synlevel_begin(ls); - while (!islast && !parse_isend(ls->tok)) { - islast = parse_stmt(ls); - lex_opt(ls, ';'); - lua_assert(ls->fs->framesize >= ls->fs->freereg && - ls->fs->freereg >= ls->fs->nactvar); - ls->fs->freereg = ls->fs->nactvar; /* Free registers after each stmt. */ - } - synlevel_end(ls); -} - -/* Entry point of bytecode parser. */ -GCproto *lj_parse(LexState *ls) -{ - FuncState fs; - FuncScope bl; - GCproto *pt; - lua_State *L = ls->L; -#ifdef LUAJIT_DISABLE_DEBUGINFO - ls->chunkname = lj_str_newlit(L, "="); -#else - ls->chunkname = lj_str_newz(L, ls->chunkarg); -#endif - setstrV(L, L->top, ls->chunkname); /* Anchor chunkname string. */ - incr_top(L); - ls->level = 0; - fs_init(ls, &fs); - fs.linedefined = 0; - fs.numparams = 0; - fs.bcbase = NULL; - fs.bclim = 0; - fs.flags |= PROTO_VARARG; /* Main chunk is always a vararg func. */ - fscope_begin(&fs, &bl, 0); - bcemit_AD(&fs, BC_FUNCV, 0, 0); /* Placeholder. */ - lj_lex_next(ls); /* Read-ahead first token. */ - parse_chunk(ls); - if (ls->tok != TK_eof) - err_token(ls, TK_eof); - pt = fs_finish(ls, ls->linenumber); - L->top--; /* Drop chunkname. */ - lua_assert(fs.prev == NULL); - lua_assert(ls->fs == NULL); - lua_assert(pt->sizeuv == 0); - return pt; -} - |