diff options
Diffstat (limited to 'lib/lua/src/lcode.c')
| -rw-r--r-- | lib/lua/src/lcode.c | 1428 |
1 files changed, 714 insertions, 714 deletions
diff --git a/lib/lua/src/lcode.c b/lib/lua/src/lcode.c index fc4a146..a873ed8 100644 --- a/lib/lua/src/lcode.c +++ b/lib/lua/src/lcode.c @@ -1,714 +1,714 @@ -/* -** $Id: lcode.c,v 1.2 2003-12-11 16:53:30 pixel Exp $ -** Code generator for Lua -** See Copyright Notice in lua.h -*/ - - -#include <stdlib.h> - -#define lcode_c - -#include "lua.h" - -#include "lcode.h" -#include "ldebug.h" -#include "ldo.h" -#include "llex.h" -#include "lmem.h" -#include "lobject.h" -#include "lopcodes.h" -#include "lparser.h" -#include "ltable.h" - - -#define hasjumps(e) ((e)->t != (e)->f) - - -void luaK_nil (FuncState *fs, int from, int n) { - Instruction *previous; - if (fs->pc > fs->lasttarget && /* no jumps to current position? */ - GET_OPCODE(*(previous = &fs->f->code[fs->pc-1])) == OP_LOADNIL) { - int pfrom = GETARG_A(*previous); - int pto = GETARG_B(*previous); - if (pfrom <= from && from <= pto+1) { /* can connect both? */ - if (from+n-1 > pto) - SETARG_B(*previous, from+n-1); - return; - } - } - luaK_codeABC(fs, OP_LOADNIL, from, from+n-1, 0); /* else no optimization */ -} - - -int luaK_jump (FuncState *fs) { - int jpc = fs->jpc; /* save list of jumps to here */ - int j; - fs->jpc = NO_JUMP; - j = luaK_codeAsBx(fs, OP_JMP, 0, NO_JUMP); - luaK_concat(fs, &j, jpc); /* keep them on hold */ - return j; -} - - -static int luaK_condjump (FuncState *fs, OpCode op, int A, int B, int C) { - luaK_codeABC(fs, op, A, B, C); - return luaK_jump(fs); -} - - -static void luaK_fixjump (FuncState *fs, int pc, int dest) { - Instruction *jmp = &fs->f->code[pc]; - int offset = dest-(pc+1); - lua_assert(dest != NO_JUMP); - if (abs(offset) > MAXARG_sBx) - luaX_syntaxerror(fs->ls, "control structure too long"); - SETARG_sBx(*jmp, offset); -} - - -/* -** returns current `pc' and marks it as a jump target (to avoid wrong -** optimizations with consecutive instructions not in the same basic block). -*/ -int luaK_getlabel (FuncState *fs) { - fs->lasttarget = fs->pc; - return fs->pc; -} - - -static int luaK_getjump (FuncState *fs, int pc) { - int offset = GETARG_sBx(fs->f->code[pc]); - if (offset == NO_JUMP) /* point to itself represents end of list */ - return NO_JUMP; /* end of list */ - else - return (pc+1)+offset; /* turn offset into absolute position */ -} - - -static Instruction *getjumpcontrol (FuncState *fs, int pc) { - Instruction *pi = &fs->f->code[pc]; - if (pc >= 1 && testOpMode(GET_OPCODE(*(pi-1)), OpModeT)) - return pi-1; - else - return pi; -} - - -/* -** check whether list has any jump that do not produce a value -** (or produce an inverted value) -*/ -static int need_value (FuncState *fs, int list, int cond) { - for (; list != NO_JUMP; list = luaK_getjump(fs, list)) { - Instruction i = *getjumpcontrol(fs, list); - if (GET_OPCODE(i) != OP_TEST || GETARG_C(i) != cond) return 1; - } - return 0; /* not found */ -} - - -static void patchtestreg (Instruction *i, int reg) { - if (reg == NO_REG) reg = GETARG_B(*i); - SETARG_A(*i, reg); -} - - -static void luaK_patchlistaux (FuncState *fs, int list, - int ttarget, int treg, int ftarget, int freg, int dtarget) { - while (list != NO_JUMP) { - int next = luaK_getjump(fs, list); - Instruction *i = getjumpcontrol(fs, list); - if (GET_OPCODE(*i) != OP_TEST) { - lua_assert(dtarget != NO_JUMP); - luaK_fixjump(fs, list, dtarget); /* jump to default target */ - } - else { - if (GETARG_C(*i)) { - lua_assert(ttarget != NO_JUMP); - patchtestreg(i, treg); - luaK_fixjump(fs, list, ttarget); - } - else { - lua_assert(ftarget != NO_JUMP); - patchtestreg(i, freg); - luaK_fixjump(fs, list, ftarget); - } - } - list = next; - } -} - - -static void luaK_dischargejpc (FuncState *fs) { - luaK_patchlistaux(fs, fs->jpc, fs->pc, NO_REG, fs->pc, NO_REG, fs->pc); - fs->jpc = NO_JUMP; -} - - -void luaK_patchlist (FuncState *fs, int list, int target) { - if (target == fs->pc) - luaK_patchtohere(fs, list); - else { - lua_assert(target < fs->pc); - luaK_patchlistaux(fs, list, target, NO_REG, target, NO_REG, target); - } -} - - -void luaK_patchtohere (FuncState *fs, int list) { - luaK_getlabel(fs); - luaK_concat(fs, &fs->jpc, list); -} - - -void luaK_concat (FuncState *fs, int *l1, int l2) { - if (l2 == NO_JUMP) return; - else if (*l1 == NO_JUMP) - *l1 = l2; - else { - int list = *l1; - int next; - while ((next = luaK_getjump(fs, list)) != NO_JUMP) /* find last element */ - list = next; - luaK_fixjump(fs, list, l2); - } -} - - -void luaK_checkstack (FuncState *fs, int n) { - int newstack = fs->freereg + n; - if (newstack > fs->f->maxstacksize) { - if (newstack >= MAXSTACK) - luaX_syntaxerror(fs->ls, "function or expression too complex"); - fs->f->maxstacksize = cast(lu_byte, newstack); - } -} - - -void luaK_reserveregs (FuncState *fs, int n) { - luaK_checkstack(fs, n); - fs->freereg += n; -} - - -static void freereg (FuncState *fs, int reg) { - if (reg >= fs->nactvar && reg < MAXSTACK) { - fs->freereg--; - lua_assert(reg == fs->freereg); - } -} - - -static void freeexp (FuncState *fs, expdesc *e) { - if (e->k == VNONRELOC) - freereg(fs, e->info); -} - - -static int addk (FuncState *fs, TObject *k, TObject *v) { - const TObject *idx = luaH_get(fs->h, k); - if (ttisnumber(idx)) { - lua_assert(luaO_rawequalObj(&fs->f->k[cast(int, nvalue(idx))], v)); - return cast(int, nvalue(idx)); - } - else { /* constant not found; create a new entry */ - Proto *f = fs->f; - luaM_growvector(fs->L, f->k, fs->nk, f->sizek, TObject, - MAXARG_Bx, "constant table overflow"); - setobj2n(&f->k[fs->nk], v); - setnvalue(luaH_set(fs->L, fs->h, k), cast(lua_Number, fs->nk)); - return fs->nk++; - } -} - - -int luaK_stringK (FuncState *fs, TString *s) { - TObject o; - setsvalue(&o, s); - return addk(fs, &o, &o); -} - - -int luaK_numberK (FuncState *fs, lua_Number r) { - TObject o; - setnvalue(&o, r); - return addk(fs, &o, &o); -} - - -static int nil_constant (FuncState *fs) { - TObject k, v; - setnilvalue(&v); - sethvalue(&k, fs->h); /* cannot use nil as key; instead use table itself */ - return addk(fs, &k, &v); -} - - -void luaK_setcallreturns (FuncState *fs, expdesc *e, int nresults) { - if (e->k == VCALL) { /* expression is an open function call? */ - SETARG_C(getcode(fs, e), nresults+1); - if (nresults == 1) { /* `regular' expression? */ - e->k = VNONRELOC; - e->info = GETARG_A(getcode(fs, e)); - } - } -} - - -void luaK_dischargevars (FuncState *fs, expdesc *e) { - switch (e->k) { - case VLOCAL: { - e->k = VNONRELOC; - break; - } - case VUPVAL: { - e->info = luaK_codeABC(fs, OP_GETUPVAL, 0, e->info, 0); - e->k = VRELOCABLE; - break; - } - case VGLOBAL: { - e->info = luaK_codeABx(fs, OP_GETGLOBAL, 0, e->info); - e->k = VRELOCABLE; - break; - } - case VINDEXED: { - freereg(fs, e->aux); - freereg(fs, e->info); - e->info = luaK_codeABC(fs, OP_GETTABLE, 0, e->info, e->aux); - e->k = VRELOCABLE; - break; - } - case VCALL: { - luaK_setcallreturns(fs, e, 1); - break; - } - default: break; /* there is one value available (somewhere) */ - } -} - - -static int code_label (FuncState *fs, int A, int b, int jump) { - luaK_getlabel(fs); /* those instructions may be jump targets */ - return luaK_codeABC(fs, OP_LOADBOOL, A, b, jump); -} - - -static void discharge2reg (FuncState *fs, expdesc *e, int reg) { - luaK_dischargevars(fs, e); - switch (e->k) { - case VNIL: { - luaK_nil(fs, reg, 1); - break; - } - case VFALSE: case VTRUE: { - luaK_codeABC(fs, OP_LOADBOOL, reg, e->k == VTRUE, 0); - break; - } - case VK: { - luaK_codeABx(fs, OP_LOADK, reg, e->info); - break; - } - case VRELOCABLE: { - Instruction *pc = &getcode(fs, e); - SETARG_A(*pc, reg); - break; - } - case VNONRELOC: { - if (reg != e->info) - luaK_codeABC(fs, OP_MOVE, reg, e->info, 0); - break; - } - default: { - lua_assert(e->k == VVOID || e->k == VJMP); - return; /* nothing to do... */ - } - } - e->info = reg; - e->k = VNONRELOC; -} - - -static void discharge2anyreg (FuncState *fs, expdesc *e) { - if (e->k != VNONRELOC) { - luaK_reserveregs(fs, 1); - discharge2reg(fs, e, fs->freereg-1); - } -} - - -static void luaK_exp2reg (FuncState *fs, expdesc *e, int reg) { - discharge2reg(fs, e, reg); - if (e->k == VJMP) - luaK_concat(fs, &e->t, e->info); /* put this jump in `t' list */ - if (hasjumps(e)) { - int final; /* position after whole expression */ - int p_f = NO_JUMP; /* position of an eventual LOAD false */ - int p_t = NO_JUMP; /* position of an eventual LOAD true */ - if (need_value(fs, e->t, 1) || need_value(fs, e->f, 0)) { - int fj = NO_JUMP; /* first jump (over LOAD ops.) */ - if (e->k != VJMP) - fj = luaK_jump(fs); - p_f = code_label(fs, reg, 0, 1); - p_t = code_label(fs, reg, 1, 0); - luaK_patchtohere(fs, fj); - } - final = luaK_getlabel(fs); - luaK_patchlistaux(fs, e->f, p_f, NO_REG, final, reg, p_f); - luaK_patchlistaux(fs, e->t, final, reg, p_t, NO_REG, p_t); - } - e->f = e->t = NO_JUMP; - e->info = reg; - e->k = VNONRELOC; -} - - -void luaK_exp2nextreg (FuncState *fs, expdesc *e) { - luaK_dischargevars(fs, e); - freeexp(fs, e); - luaK_reserveregs(fs, 1); - luaK_exp2reg(fs, e, fs->freereg - 1); -} - - -int luaK_exp2anyreg (FuncState *fs, expdesc *e) { - luaK_dischargevars(fs, e); - if (e->k == VNONRELOC) { - if (!hasjumps(e)) return e->info; /* exp is already in a register */ - if (e->info >= fs->nactvar) { /* reg. is not a local? */ - luaK_exp2reg(fs, e, e->info); /* put value on it */ - return e->info; - } - } - luaK_exp2nextreg(fs, e); /* default */ - return e->info; -} - - -void luaK_exp2val (FuncState *fs, expdesc *e) { - if (hasjumps(e)) - luaK_exp2anyreg(fs, e); - else - luaK_dischargevars(fs, e); -} - - -int luaK_exp2RK (FuncState *fs, expdesc *e) { - luaK_exp2val(fs, e); - switch (e->k) { - case VNIL: { - if (fs->nk + MAXSTACK <= MAXARG_C) { /* constant fit in argC? */ - e->info = nil_constant(fs); - e->k = VK; - return e->info + MAXSTACK; - } - else break; - } - case VK: { - if (e->info + MAXSTACK <= MAXARG_C) /* constant fit in argC? */ - return e->info + MAXSTACK; - else break; - } - default: break; - } - /* not a constant in the right range: put it in a register */ - return luaK_exp2anyreg(fs, e); -} - - -void luaK_storevar (FuncState *fs, expdesc *var, expdesc *exp) { - switch (var->k) { - case VLOCAL: { - freeexp(fs, exp); - luaK_exp2reg(fs, exp, var->info); - return; - } - case VUPVAL: { - int e = luaK_exp2anyreg(fs, exp); - luaK_codeABC(fs, OP_SETUPVAL, e, var->info, 0); - break; - } - case VGLOBAL: { - int e = luaK_exp2anyreg(fs, exp); - luaK_codeABx(fs, OP_SETGLOBAL, e, var->info); - break; - } - case VINDEXED: { - int e = luaK_exp2RK(fs, exp); - luaK_codeABC(fs, OP_SETTABLE, var->info, var->aux, e); - break; - } - default: { - lua_assert(0); /* invalid var kind to store */ - break; - } - } - freeexp(fs, exp); -} - - -void luaK_self (FuncState *fs, expdesc *e, expdesc *key) { - int func; - luaK_exp2anyreg(fs, e); - freeexp(fs, e); - func = fs->freereg; - luaK_reserveregs(fs, 2); - luaK_codeABC(fs, OP_SELF, func, e->info, luaK_exp2RK(fs, key)); - freeexp(fs, key); - e->info = func; - e->k = VNONRELOC; -} - - -static void invertjump (FuncState *fs, expdesc *e) { - Instruction *pc = getjumpcontrol(fs, e->info); - lua_assert(testOpMode(GET_OPCODE(*pc), OpModeT) && - GET_OPCODE(*pc) != OP_TEST); - SETARG_A(*pc, !(GETARG_A(*pc))); -} - - -static int jumponcond (FuncState *fs, expdesc *e, int cond) { - if (e->k == VRELOCABLE) { - Instruction ie = getcode(fs, e); - if (GET_OPCODE(ie) == OP_NOT) { - fs->pc--; /* remove previous OP_NOT */ - return luaK_condjump(fs, OP_TEST, NO_REG, GETARG_B(ie), !cond); - } - /* else go through */ - } - discharge2anyreg(fs, e); - freeexp(fs, e); - return luaK_condjump(fs, OP_TEST, NO_REG, e->info, cond); -} - - -void luaK_goiftrue (FuncState *fs, expdesc *e) { - int pc; /* pc of last jump */ - luaK_dischargevars(fs, e); - switch (e->k) { - case VK: case VTRUE: { - pc = NO_JUMP; /* always true; do nothing */ - break; - } - case VFALSE: { - pc = luaK_jump(fs); /* always jump */ - break; - } - case VJMP: { - invertjump(fs, e); - pc = e->info; - break; - } - default: { - pc = jumponcond(fs, e, 0); - break; - } - } - luaK_concat(fs, &e->f, pc); /* insert last jump in `f' list */ -} - - -void luaK_goiffalse (FuncState *fs, expdesc *e) { - int pc; /* pc of last jump */ - luaK_dischargevars(fs, e); - switch (e->k) { - case VNIL: case VFALSE: { - pc = NO_JUMP; /* always false; do nothing */ - break; - } - case VTRUE: { - pc = luaK_jump(fs); /* always jump */ - break; - } - case VJMP: { - pc = e->info; - break; - } - default: { - pc = jumponcond(fs, e, 1); - break; - } - } - luaK_concat(fs, &e->t, pc); /* insert last jump in `t' list */ -} - - -static void codenot (FuncState *fs, expdesc *e) { - luaK_dischargevars(fs, e); - switch (e->k) { - case VNIL: case VFALSE: { - e->k = VTRUE; - break; - } - case VK: case VTRUE: { - e->k = VFALSE; - break; - } - case VJMP: { - invertjump(fs, e); - break; - } - case VRELOCABLE: - case VNONRELOC: { - discharge2anyreg(fs, e); - freeexp(fs, e); - e->info = luaK_codeABC(fs, OP_NOT, 0, e->info, 0); - e->k = VRELOCABLE; - break; - } - default: { - lua_assert(0); /* cannot happen */ - break; - } - } - /* interchange true and false lists */ - { int temp = e->f; e->f = e->t; e->t = temp; } -} - - -void luaK_indexed (FuncState *fs, expdesc *t, expdesc *k) { - t->aux = luaK_exp2RK(fs, k); - t->k = VINDEXED; -} - - -void luaK_prefix (FuncState *fs, UnOpr op, expdesc *e) { - if (op == OPR_MINUS) { - luaK_exp2val(fs, e); - if (e->k == VK && ttisnumber(&fs->f->k[e->info])) - e->info = luaK_numberK(fs, -nvalue(&fs->f->k[e->info])); - else { - luaK_exp2anyreg(fs, e); - freeexp(fs, e); - e->info = luaK_codeABC(fs, OP_UNM, 0, e->info, 0); - e->k = VRELOCABLE; - } - } - else /* op == NOT */ - codenot(fs, e); -} - - -void luaK_infix (FuncState *fs, BinOpr op, expdesc *v) { - switch (op) { - case OPR_AND: { - luaK_goiftrue(fs, v); - luaK_patchtohere(fs, v->t); - v->t = NO_JUMP; - break; - } - case OPR_OR: { - luaK_goiffalse(fs, v); - luaK_patchtohere(fs, v->f); - v->f = NO_JUMP; - break; - } - case OPR_CONCAT: { - luaK_exp2nextreg(fs, v); /* operand must be on the `stack' */ - break; - } - default: { - luaK_exp2RK(fs, v); - break; - } - } -} - - -static void codebinop (FuncState *fs, expdesc *res, BinOpr op, - int o1, int o2) { - if (op <= OPR_POW) { /* arithmetic operator? */ - OpCode opc = cast(OpCode, (op - OPR_ADD) + OP_ADD); /* ORDER OP */ - res->info = luaK_codeABC(fs, opc, 0, o1, o2); - res->k = VRELOCABLE; - } - else { /* test operator */ - static const OpCode ops[] = {OP_EQ, OP_EQ, OP_LT, OP_LE, OP_LT, OP_LE}; - int cond = 1; - if (op >= OPR_GT) { /* `>' or `>='? */ - int temp; /* exchange args and replace by `<' or `<=' */ - temp = o1; o1 = o2; o2 = temp; /* o1 <==> o2 */ - } - else if (op == OPR_NE) cond = 0; - res->info = luaK_condjump(fs, ops[op - OPR_NE], cond, o1, o2); - res->k = VJMP; - } -} - - -void luaK_posfix (FuncState *fs, BinOpr op, expdesc *e1, expdesc *e2) { - switch (op) { - case OPR_AND: { - lua_assert(e1->t == NO_JUMP); /* list must be closed */ - luaK_dischargevars(fs, e2); - luaK_concat(fs, &e1->f, e2->f); - e1->k = e2->k; e1->info = e2->info; e1->aux = e2->aux; e1->t = e2->t; - break; - } - case OPR_OR: { - lua_assert(e1->f == NO_JUMP); /* list must be closed */ - luaK_dischargevars(fs, e2); - luaK_concat(fs, &e1->t, e2->t); - e1->k = e2->k; e1->info = e2->info; e1->aux = e2->aux; e1->f = e2->f; - break; - } - case OPR_CONCAT: { - luaK_exp2val(fs, e2); - if (e2->k == VRELOCABLE && GET_OPCODE(getcode(fs, e2)) == OP_CONCAT) { - lua_assert(e1->info == GETARG_B(getcode(fs, e2))-1); - freeexp(fs, e1); - SETARG_B(getcode(fs, e2), e1->info); - e1->k = e2->k; e1->info = e2->info; - } - else { - luaK_exp2nextreg(fs, e2); - freeexp(fs, e2); - freeexp(fs, e1); - e1->info = luaK_codeABC(fs, OP_CONCAT, 0, e1->info, e2->info); - e1->k = VRELOCABLE; - } - break; - } - default: { - int o1 = luaK_exp2RK(fs, e1); - int o2 = luaK_exp2RK(fs, e2); - freeexp(fs, e2); - freeexp(fs, e1); - codebinop(fs, e1, op, o1, o2); - } - } -} - - -void luaK_fixline (FuncState *fs, int line) { - fs->f->lineinfo[fs->pc - 1] = line; -} - - -int luaK_code (FuncState *fs, Instruction i, int line) { - Proto *f = fs->f; - luaK_dischargejpc(fs); /* `pc' will change */ - /* put new instruction in code array */ - luaM_growvector(fs->L, f->code, fs->pc, f->sizecode, Instruction, - MAX_INT, "code size overflow"); - f->code[fs->pc] = i; - /* save corresponding line information */ - luaM_growvector(fs->L, f->lineinfo, fs->pc, f->sizelineinfo, int, - MAX_INT, "code size overflow"); - f->lineinfo[fs->pc] = line; - return fs->pc++; -} - - -int luaK_codeABC (FuncState *fs, OpCode o, int a, int b, int c) { - lua_assert(getOpMode(o) == iABC); - return luaK_code(fs, CREATE_ABC(o, a, b, c), fs->ls->lastline); -} - - -int luaK_codeABx (FuncState *fs, OpCode o, int a, unsigned int bc) { - lua_assert(getOpMode(o) == iABx || getOpMode(o) == iAsBx); - return luaK_code(fs, CREATE_ABx(o, a, bc), fs->ls->lastline); -} - +/*
+** $Id: lcode.c,v 1.3 2004-11-27 21:35:20 pixel Exp $
+** Code generator for Lua
+** See Copyright Notice in lua.h
+*/
+
+
+#include <stdlib.h>
+
+#define lcode_c
+
+#include "lua.h"
+
+#include "lcode.h"
+#include "ldebug.h"
+#include "ldo.h"
+#include "llex.h"
+#include "lmem.h"
+#include "lobject.h"
+#include "lopcodes.h"
+#include "lparser.h"
+#include "ltable.h"
+
+
+#define hasjumps(e) ((e)->t != (e)->f)
+
+
+void luaK_nil (FuncState *fs, int from, int n) {
+ Instruction *previous;
+ if (fs->pc > fs->lasttarget && /* no jumps to current position? */
+ GET_OPCODE(*(previous = &fs->f->code[fs->pc-1])) == OP_LOADNIL) {
+ int pfrom = GETARG_A(*previous);
+ int pto = GETARG_B(*previous);
+ if (pfrom <= from && from <= pto+1) { /* can connect both? */
+ if (from+n-1 > pto)
+ SETARG_B(*previous, from+n-1);
+ return;
+ }
+ }
+ luaK_codeABC(fs, OP_LOADNIL, from, from+n-1, 0); /* else no optimization */
+}
+
+
+int luaK_jump (FuncState *fs) {
+ int jpc = fs->jpc; /* save list of jumps to here */
+ int j;
+ fs->jpc = NO_JUMP;
+ j = luaK_codeAsBx(fs, OP_JMP, 0, NO_JUMP);
+ luaK_concat(fs, &j, jpc); /* keep them on hold */
+ return j;
+}
+
+
+static int luaK_condjump (FuncState *fs, OpCode op, int A, int B, int C) {
+ luaK_codeABC(fs, op, A, B, C);
+ return luaK_jump(fs);
+}
+
+
+static void luaK_fixjump (FuncState *fs, int pc, int dest) {
+ Instruction *jmp = &fs->f->code[pc];
+ int offset = dest-(pc+1);
+ lua_assert(dest != NO_JUMP);
+ if (abs(offset) > MAXARG_sBx)
+ luaX_syntaxerror(fs->ls, "control structure too long");
+ SETARG_sBx(*jmp, offset);
+}
+
+
+/*
+** returns current `pc' and marks it as a jump target (to avoid wrong
+** optimizations with consecutive instructions not in the same basic block).
+*/
+int luaK_getlabel (FuncState *fs) {
+ fs->lasttarget = fs->pc;
+ return fs->pc;
+}
+
+
+static int luaK_getjump (FuncState *fs, int pc) {
+ int offset = GETARG_sBx(fs->f->code[pc]);
+ if (offset == NO_JUMP) /* point to itself represents end of list */
+ return NO_JUMP; /* end of list */
+ else
+ return (pc+1)+offset; /* turn offset into absolute position */
+}
+
+
+static Instruction *getjumpcontrol (FuncState *fs, int pc) {
+ Instruction *pi = &fs->f->code[pc];
+ if (pc >= 1 && testOpMode(GET_OPCODE(*(pi-1)), OpModeT))
+ return pi-1;
+ else
+ return pi;
+}
+
+
+/*
+** check whether list has any jump that do not produce a value
+** (or produce an inverted value)
+*/
+static int need_value (FuncState *fs, int list, int cond) {
+ for (; list != NO_JUMP; list = luaK_getjump(fs, list)) {
+ Instruction i = *getjumpcontrol(fs, list);
+ if (GET_OPCODE(i) != OP_TEST || GETARG_C(i) != cond) return 1;
+ }
+ return 0; /* not found */
+}
+
+
+static void patchtestreg (Instruction *i, int reg) {
+ if (reg == NO_REG) reg = GETARG_B(*i);
+ SETARG_A(*i, reg);
+}
+
+
+static void luaK_patchlistaux (FuncState *fs, int list,
+ int ttarget, int treg, int ftarget, int freg, int dtarget) {
+ while (list != NO_JUMP) {
+ int next = luaK_getjump(fs, list);
+ Instruction *i = getjumpcontrol(fs, list);
+ if (GET_OPCODE(*i) != OP_TEST) {
+ lua_assert(dtarget != NO_JUMP);
+ luaK_fixjump(fs, list, dtarget); /* jump to default target */
+ }
+ else {
+ if (GETARG_C(*i)) {
+ lua_assert(ttarget != NO_JUMP);
+ patchtestreg(i, treg);
+ luaK_fixjump(fs, list, ttarget);
+ }
+ else {
+ lua_assert(ftarget != NO_JUMP);
+ patchtestreg(i, freg);
+ luaK_fixjump(fs, list, ftarget);
+ }
+ }
+ list = next;
+ }
+}
+
+
+static void luaK_dischargejpc (FuncState *fs) {
+ luaK_patchlistaux(fs, fs->jpc, fs->pc, NO_REG, fs->pc, NO_REG, fs->pc);
+ fs->jpc = NO_JUMP;
+}
+
+
+void luaK_patchlist (FuncState *fs, int list, int target) {
+ if (target == fs->pc)
+ luaK_patchtohere(fs, list);
+ else {
+ lua_assert(target < fs->pc);
+ luaK_patchlistaux(fs, list, target, NO_REG, target, NO_REG, target);
+ }
+}
+
+
+void luaK_patchtohere (FuncState *fs, int list) {
+ luaK_getlabel(fs);
+ luaK_concat(fs, &fs->jpc, list);
+}
+
+
+void luaK_concat (FuncState *fs, int *l1, int l2) {
+ if (l2 == NO_JUMP) return;
+ else if (*l1 == NO_JUMP)
+ *l1 = l2;
+ else {
+ int list = *l1;
+ int next;
+ while ((next = luaK_getjump(fs, list)) != NO_JUMP) /* find last element */
+ list = next;
+ luaK_fixjump(fs, list, l2);
+ }
+}
+
+
+void luaK_checkstack (FuncState *fs, int n) {
+ int newstack = fs->freereg + n;
+ if (newstack > fs->f->maxstacksize) {
+ if (newstack >= MAXSTACK)
+ luaX_syntaxerror(fs->ls, "function or expression too complex");
+ fs->f->maxstacksize = cast(lu_byte, newstack);
+ }
+}
+
+
+void luaK_reserveregs (FuncState *fs, int n) {
+ luaK_checkstack(fs, n);
+ fs->freereg += n;
+}
+
+
+static void freereg (FuncState *fs, int reg) {
+ if (reg >= fs->nactvar && reg < MAXSTACK) {
+ fs->freereg--;
+ lua_assert(reg == fs->freereg);
+ }
+}
+
+
+static void freeexp (FuncState *fs, expdesc *e) {
+ if (e->k == VNONRELOC)
+ freereg(fs, e->info);
+}
+
+
+static int addk (FuncState *fs, TObject *k, TObject *v) {
+ const TObject *idx = luaH_get(fs->h, k);
+ if (ttisnumber(idx)) {
+ lua_assert(luaO_rawequalObj(&fs->f->k[cast(int, nvalue(idx))], v));
+ return cast(int, nvalue(idx));
+ }
+ else { /* constant not found; create a new entry */
+ Proto *f = fs->f;
+ luaM_growvector(fs->L, f->k, fs->nk, f->sizek, TObject,
+ MAXARG_Bx, "constant table overflow");
+ setobj2n(&f->k[fs->nk], v);
+ setnvalue(luaH_set(fs->L, fs->h, k), cast(lua_Number, fs->nk));
+ return fs->nk++;
+ }
+}
+
+
+int luaK_stringK (FuncState *fs, TString *s) {
+ TObject o;
+ setsvalue(&o, s);
+ return addk(fs, &o, &o);
+}
+
+
+int luaK_numberK (FuncState *fs, lua_Number r) {
+ TObject o;
+ setnvalue(&o, r);
+ return addk(fs, &o, &o);
+}
+
+
+static int nil_constant (FuncState *fs) {
+ TObject k, v;
+ setnilvalue(&v);
+ sethvalue(&k, fs->h); /* cannot use nil as key; instead use table itself */
+ return addk(fs, &k, &v);
+}
+
+
+void luaK_setcallreturns (FuncState *fs, expdesc *e, int nresults) {
+ if (e->k == VCALL) { /* expression is an open function call? */
+ SETARG_C(getcode(fs, e), nresults+1);
+ if (nresults == 1) { /* `regular' expression? */
+ e->k = VNONRELOC;
+ e->info = GETARG_A(getcode(fs, e));
+ }
+ }
+}
+
+
+void luaK_dischargevars (FuncState *fs, expdesc *e) {
+ switch (e->k) {
+ case VLOCAL: {
+ e->k = VNONRELOC;
+ break;
+ }
+ case VUPVAL: {
+ e->info = luaK_codeABC(fs, OP_GETUPVAL, 0, e->info, 0);
+ e->k = VRELOCABLE;
+ break;
+ }
+ case VGLOBAL: {
+ e->info = luaK_codeABx(fs, OP_GETGLOBAL, 0, e->info);
+ e->k = VRELOCABLE;
+ break;
+ }
+ case VINDEXED: {
+ freereg(fs, e->aux);
+ freereg(fs, e->info);
+ e->info = luaK_codeABC(fs, OP_GETTABLE, 0, e->info, e->aux);
+ e->k = VRELOCABLE;
+ break;
+ }
+ case VCALL: {
+ luaK_setcallreturns(fs, e, 1);
+ break;
+ }
+ default: break; /* there is one value available (somewhere) */
+ }
+}
+
+
+static int code_label (FuncState *fs, int A, int b, int jump) {
+ luaK_getlabel(fs); /* those instructions may be jump targets */
+ return luaK_codeABC(fs, OP_LOADBOOL, A, b, jump);
+}
+
+
+static void discharge2reg (FuncState *fs, expdesc *e, int reg) {
+ luaK_dischargevars(fs, e);
+ switch (e->k) {
+ case VNIL: {
+ luaK_nil(fs, reg, 1);
+ break;
+ }
+ case VFALSE: case VTRUE: {
+ luaK_codeABC(fs, OP_LOADBOOL, reg, e->k == VTRUE, 0);
+ break;
+ }
+ case VK: {
+ luaK_codeABx(fs, OP_LOADK, reg, e->info);
+ break;
+ }
+ case VRELOCABLE: {
+ Instruction *pc = &getcode(fs, e);
+ SETARG_A(*pc, reg);
+ break;
+ }
+ case VNONRELOC: {
+ if (reg != e->info)
+ luaK_codeABC(fs, OP_MOVE, reg, e->info, 0);
+ break;
+ }
+ default: {
+ lua_assert(e->k == VVOID || e->k == VJMP);
+ return; /* nothing to do... */
+ }
+ }
+ e->info = reg;
+ e->k = VNONRELOC;
+}
+
+
+static void discharge2anyreg (FuncState *fs, expdesc *e) {
+ if (e->k != VNONRELOC) {
+ luaK_reserveregs(fs, 1);
+ discharge2reg(fs, e, fs->freereg-1);
+ }
+}
+
+
+static void luaK_exp2reg (FuncState *fs, expdesc *e, int reg) {
+ discharge2reg(fs, e, reg);
+ if (e->k == VJMP)
+ luaK_concat(fs, &e->t, e->info); /* put this jump in `t' list */
+ if (hasjumps(e)) {
+ int final; /* position after whole expression */
+ int p_f = NO_JUMP; /* position of an eventual LOAD false */
+ int p_t = NO_JUMP; /* position of an eventual LOAD true */
+ if (need_value(fs, e->t, 1) || need_value(fs, e->f, 0)) {
+ int fj = NO_JUMP; /* first jump (over LOAD ops.) */
+ if (e->k != VJMP)
+ fj = luaK_jump(fs);
+ p_f = code_label(fs, reg, 0, 1);
+ p_t = code_label(fs, reg, 1, 0);
+ luaK_patchtohere(fs, fj);
+ }
+ final = luaK_getlabel(fs);
+ luaK_patchlistaux(fs, e->f, p_f, NO_REG, final, reg, p_f);
+ luaK_patchlistaux(fs, e->t, final, reg, p_t, NO_REG, p_t);
+ }
+ e->f = e->t = NO_JUMP;
+ e->info = reg;
+ e->k = VNONRELOC;
+}
+
+
+void luaK_exp2nextreg (FuncState *fs, expdesc *e) {
+ luaK_dischargevars(fs, e);
+ freeexp(fs, e);
+ luaK_reserveregs(fs, 1);
+ luaK_exp2reg(fs, e, fs->freereg - 1);
+}
+
+
+int luaK_exp2anyreg (FuncState *fs, expdesc *e) {
+ luaK_dischargevars(fs, e);
+ if (e->k == VNONRELOC) {
+ if (!hasjumps(e)) return e->info; /* exp is already in a register */
+ if (e->info >= fs->nactvar) { /* reg. is not a local? */
+ luaK_exp2reg(fs, e, e->info); /* put value on it */
+ return e->info;
+ }
+ }
+ luaK_exp2nextreg(fs, e); /* default */
+ return e->info;
+}
+
+
+void luaK_exp2val (FuncState *fs, expdesc *e) {
+ if (hasjumps(e))
+ luaK_exp2anyreg(fs, e);
+ else
+ luaK_dischargevars(fs, e);
+}
+
+
+int luaK_exp2RK (FuncState *fs, expdesc *e) {
+ luaK_exp2val(fs, e);
+ switch (e->k) {
+ case VNIL: {
+ if (fs->nk + MAXSTACK <= MAXARG_C) { /* constant fit in argC? */
+ e->info = nil_constant(fs);
+ e->k = VK;
+ return e->info + MAXSTACK;
+ }
+ else break;
+ }
+ case VK: {
+ if (e->info + MAXSTACK <= MAXARG_C) /* constant fit in argC? */
+ return e->info + MAXSTACK;
+ else break;
+ }
+ default: break;
+ }
+ /* not a constant in the right range: put it in a register */
+ return luaK_exp2anyreg(fs, e);
+}
+
+
+void luaK_storevar (FuncState *fs, expdesc *var, expdesc *exp) {
+ switch (var->k) {
+ case VLOCAL: {
+ freeexp(fs, exp);
+ luaK_exp2reg(fs, exp, var->info);
+ return;
+ }
+ case VUPVAL: {
+ int e = luaK_exp2anyreg(fs, exp);
+ luaK_codeABC(fs, OP_SETUPVAL, e, var->info, 0);
+ break;
+ }
+ case VGLOBAL: {
+ int e = luaK_exp2anyreg(fs, exp);
+ luaK_codeABx(fs, OP_SETGLOBAL, e, var->info);
+ break;
+ }
+ case VINDEXED: {
+ int e = luaK_exp2RK(fs, exp);
+ luaK_codeABC(fs, OP_SETTABLE, var->info, var->aux, e);
+ break;
+ }
+ default: {
+ lua_assert(0); /* invalid var kind to store */
+ break;
+ }
+ }
+ freeexp(fs, exp);
+}
+
+
+void luaK_self (FuncState *fs, expdesc *e, expdesc *key) {
+ int func;
+ luaK_exp2anyreg(fs, e);
+ freeexp(fs, e);
+ func = fs->freereg;
+ luaK_reserveregs(fs, 2);
+ luaK_codeABC(fs, OP_SELF, func, e->info, luaK_exp2RK(fs, key));
+ freeexp(fs, key);
+ e->info = func;
+ e->k = VNONRELOC;
+}
+
+
+static void invertjump (FuncState *fs, expdesc *e) {
+ Instruction *pc = getjumpcontrol(fs, e->info);
+ lua_assert(testOpMode(GET_OPCODE(*pc), OpModeT) &&
+ GET_OPCODE(*pc) != OP_TEST);
+ SETARG_A(*pc, !(GETARG_A(*pc)));
+}
+
+
+static int jumponcond (FuncState *fs, expdesc *e, int cond) {
+ if (e->k == VRELOCABLE) {
+ Instruction ie = getcode(fs, e);
+ if (GET_OPCODE(ie) == OP_NOT) {
+ fs->pc--; /* remove previous OP_NOT */
+ return luaK_condjump(fs, OP_TEST, NO_REG, GETARG_B(ie), !cond);
+ }
+ /* else go through */
+ }
+ discharge2anyreg(fs, e);
+ freeexp(fs, e);
+ return luaK_condjump(fs, OP_TEST, NO_REG, e->info, cond);
+}
+
+
+void luaK_goiftrue (FuncState *fs, expdesc *e) {
+ int pc; /* pc of last jump */
+ luaK_dischargevars(fs, e);
+ switch (e->k) {
+ case VK: case VTRUE: {
+ pc = NO_JUMP; /* always true; do nothing */
+ break;
+ }
+ case VFALSE: {
+ pc = luaK_jump(fs); /* always jump */
+ break;
+ }
+ case VJMP: {
+ invertjump(fs, e);
+ pc = e->info;
+ break;
+ }
+ default: {
+ pc = jumponcond(fs, e, 0);
+ break;
+ }
+ }
+ luaK_concat(fs, &e->f, pc); /* insert last jump in `f' list */
+}
+
+
+void luaK_goiffalse (FuncState *fs, expdesc *e) {
+ int pc; /* pc of last jump */
+ luaK_dischargevars(fs, e);
+ switch (e->k) {
+ case VNIL: case VFALSE: {
+ pc = NO_JUMP; /* always false; do nothing */
+ break;
+ }
+ case VTRUE: {
+ pc = luaK_jump(fs); /* always jump */
+ break;
+ }
+ case VJMP: {
+ pc = e->info;
+ break;
+ }
+ default: {
+ pc = jumponcond(fs, e, 1);
+ break;
+ }
+ }
+ luaK_concat(fs, &e->t, pc); /* insert last jump in `t' list */
+}
+
+
+static void codenot (FuncState *fs, expdesc *e) {
+ luaK_dischargevars(fs, e);
+ switch (e->k) {
+ case VNIL: case VFALSE: {
+ e->k = VTRUE;
+ break;
+ }
+ case VK: case VTRUE: {
+ e->k = VFALSE;
+ break;
+ }
+ case VJMP: {
+ invertjump(fs, e);
+ break;
+ }
+ case VRELOCABLE:
+ case VNONRELOC: {
+ discharge2anyreg(fs, e);
+ freeexp(fs, e);
+ e->info = luaK_codeABC(fs, OP_NOT, 0, e->info, 0);
+ e->k = VRELOCABLE;
+ break;
+ }
+ default: {
+ lua_assert(0); /* cannot happen */
+ break;
+ }
+ }
+ /* interchange true and false lists */
+ { int temp = e->f; e->f = e->t; e->t = temp; }
+}
+
+
+void luaK_indexed (FuncState *fs, expdesc *t, expdesc *k) {
+ t->aux = luaK_exp2RK(fs, k);
+ t->k = VINDEXED;
+}
+
+
+void luaK_prefix (FuncState *fs, UnOpr op, expdesc *e) {
+ if (op == OPR_MINUS) {
+ luaK_exp2val(fs, e);
+ if (e->k == VK && ttisnumber(&fs->f->k[e->info]))
+ e->info = luaK_numberK(fs, -nvalue(&fs->f->k[e->info]));
+ else {
+ luaK_exp2anyreg(fs, e);
+ freeexp(fs, e);
+ e->info = luaK_codeABC(fs, OP_UNM, 0, e->info, 0);
+ e->k = VRELOCABLE;
+ }
+ }
+ else /* op == NOT */
+ codenot(fs, e);
+}
+
+
+void luaK_infix (FuncState *fs, BinOpr op, expdesc *v) {
+ switch (op) {
+ case OPR_AND: {
+ luaK_goiftrue(fs, v);
+ luaK_patchtohere(fs, v->t);
+ v->t = NO_JUMP;
+ break;
+ }
+ case OPR_OR: {
+ luaK_goiffalse(fs, v);
+ luaK_patchtohere(fs, v->f);
+ v->f = NO_JUMP;
+ break;
+ }
+ case OPR_CONCAT: {
+ luaK_exp2nextreg(fs, v); /* operand must be on the `stack' */
+ break;
+ }
+ default: {
+ luaK_exp2RK(fs, v);
+ break;
+ }
+ }
+}
+
+
+static void codebinop (FuncState *fs, expdesc *res, BinOpr op,
+ int o1, int o2) {
+ if (op <= OPR_POW) { /* arithmetic operator? */
+ OpCode opc = cast(OpCode, (op - OPR_ADD) + OP_ADD); /* ORDER OP */
+ res->info = luaK_codeABC(fs, opc, 0, o1, o2);
+ res->k = VRELOCABLE;
+ }
+ else { /* test operator */
+ static const OpCode ops[] = {OP_EQ, OP_EQ, OP_LT, OP_LE, OP_LT, OP_LE};
+ int cond = 1;
+ if (op >= OPR_GT) { /* `>' or `>='? */
+ int temp; /* exchange args and replace by `<' or `<=' */
+ temp = o1; o1 = o2; o2 = temp; /* o1 <==> o2 */
+ }
+ else if (op == OPR_NE) cond = 0;
+ res->info = luaK_condjump(fs, ops[op - OPR_NE], cond, o1, o2);
+ res->k = VJMP;
+ }
+}
+
+
+void luaK_posfix (FuncState *fs, BinOpr op, expdesc *e1, expdesc *e2) {
+ switch (op) {
+ case OPR_AND: {
+ lua_assert(e1->t == NO_JUMP); /* list must be closed */
+ luaK_dischargevars(fs, e2);
+ luaK_concat(fs, &e1->f, e2->f);
+ e1->k = e2->k; e1->info = e2->info; e1->aux = e2->aux; e1->t = e2->t;
+ break;
+ }
+ case OPR_OR: {
+ lua_assert(e1->f == NO_JUMP); /* list must be closed */
+ luaK_dischargevars(fs, e2);
+ luaK_concat(fs, &e1->t, e2->t);
+ e1->k = e2->k; e1->info = e2->info; e1->aux = e2->aux; e1->f = e2->f;
+ break;
+ }
+ case OPR_CONCAT: {
+ luaK_exp2val(fs, e2);
+ if (e2->k == VRELOCABLE && GET_OPCODE(getcode(fs, e2)) == OP_CONCAT) {
+ lua_assert(e1->info == GETARG_B(getcode(fs, e2))-1);
+ freeexp(fs, e1);
+ SETARG_B(getcode(fs, e2), e1->info);
+ e1->k = e2->k; e1->info = e2->info;
+ }
+ else {
+ luaK_exp2nextreg(fs, e2);
+ freeexp(fs, e2);
+ freeexp(fs, e1);
+ e1->info = luaK_codeABC(fs, OP_CONCAT, 0, e1->info, e2->info);
+ e1->k = VRELOCABLE;
+ }
+ break;
+ }
+ default: {
+ int o1 = luaK_exp2RK(fs, e1);
+ int o2 = luaK_exp2RK(fs, e2);
+ freeexp(fs, e2);
+ freeexp(fs, e1);
+ codebinop(fs, e1, op, o1, o2);
+ }
+ }
+}
+
+
+void luaK_fixline (FuncState *fs, int line) {
+ fs->f->lineinfo[fs->pc - 1] = line;
+}
+
+
+int luaK_code (FuncState *fs, Instruction i, int line) {
+ Proto *f = fs->f;
+ luaK_dischargejpc(fs); /* `pc' will change */
+ /* put new instruction in code array */
+ luaM_growvector(fs->L, f->code, fs->pc, f->sizecode, Instruction,
+ MAX_INT, "code size overflow");
+ f->code[fs->pc] = i;
+ /* save corresponding line information */
+ luaM_growvector(fs->L, f->lineinfo, fs->pc, f->sizelineinfo, int,
+ MAX_INT, "code size overflow");
+ f->lineinfo[fs->pc] = line;
+ return fs->pc++;
+}
+
+
+int luaK_codeABC (FuncState *fs, OpCode o, int a, int b, int c) {
+ lua_assert(getOpMode(o) == iABC);
+ return luaK_code(fs, CREATE_ABC(o, a, b, c), fs->ls->lastline);
+}
+
+
+int luaK_codeABx (FuncState *fs, OpCode o, int a, unsigned int bc) {
+ lua_assert(getOpMode(o) == iABx || getOpMode(o) == iAsBx);
+ return luaK_code(fs, CREATE_ABx(o, a, bc), fs->ls->lastline);
+}
+
|