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 56e9654..fc4a146 100644 --- a/lib/lua/src/lcode.c +++ b/lib/lua/src/lcode.c @@ -1,714 +1,714 @@ -/*
-** $Id: lcode.c,v 1.1 2003-11-06 11:56:07 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 1.2 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); +} + |