--- /dev/null
+/*
+** $Id: lcode.c,v 2.62 2012/08/16 17:34:28 roberto Exp $
+** Code generator for Lua
+** See Copyright Notice in lua.h
+*/
+
+
+#include <stdlib.h>
+
+#define lcode_c
+#define LUA_CORE
+
+#include "lua.h"
+
+#include "lcode.h"
+#include "ldebug.h"
+#include "ldo.h"
+#include "lgc.h"
+#include "llex.h"
+#include "lmem.h"
+#include "lobject.h"
+#include "lopcodes.h"
+#include "lparser.h"
+#include "lstring.h"
+#include "ltable.h"
+#include "lvm.h"
+
+
+#define hasjumps(e) ((e)->t != (e)->f)
+
+
+static int isnumeral(expdesc *e) {
+ return (e->k == VKNUM && e->t == NO_JUMP && e->f == NO_JUMP);
+}
+
+
+void luaK_nil (FuncState *fs, int from, int n) {
+ Instruction *previous;
+ int l = from + n - 1; /* last register to set nil */
+ if (fs->pc > fs->lasttarget) { /* no jumps to current position? */
+ previous = &fs->f->code[fs->pc-1];
+ if (GET_OPCODE(*previous) == OP_LOADNIL) {
+ int pfrom = GETARG_A(*previous);
+ int pl = pfrom + GETARG_B(*previous);
+ if ((pfrom <= from && from <= pl + 1) ||
+ (from <= pfrom && pfrom <= l + 1)) { /* can connect both? */
+ if (pfrom < from) from = pfrom; /* from = min(from, pfrom) */
+ if (pl > l) l = pl; /* l = max(l, pl) */
+ SETARG_A(*previous, from);
+ SETARG_B(*previous, l - from);
+ return;
+ }
+ } /* else go through */
+ }
+ luaK_codeABC(fs, OP_LOADNIL, 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;
+}
+
+
+void luaK_ret (FuncState *fs, int first, int nret) {
+ luaK_codeABC(fs, OP_RETURN, first, nret+1, 0);
+}
+
+
+static int condjump (FuncState *fs, OpCode op, int A, int B, int C) {
+ luaK_codeABC(fs, op, A, B, C);
+ return luaK_jump(fs);
+}
+
+
+static void 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 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 && testTMode(GET_OPCODE(*(pi-1))))
+ 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) {
+ for (; list != NO_JUMP; list = getjump(fs, list)) {
+ Instruction i = *getjumpcontrol(fs, list);
+ if (GET_OPCODE(i) != OP_TESTSET) return 1;
+ }
+ return 0; /* not found */
+}
+
+
+static int patchtestreg (FuncState *fs, int node, int reg) {
+ Instruction *i = getjumpcontrol(fs, node);
+ if (GET_OPCODE(*i) != OP_TESTSET)
+ return 0; /* cannot patch other instructions */
+ if (reg != NO_REG && reg != GETARG_B(*i))
+ SETARG_A(*i, reg);
+ else /* no register to put value or register already has the value */
+ *i = CREATE_ABC(OP_TEST, GETARG_B(*i), 0, GETARG_C(*i));
+
+ return 1;
+}
+
+
+static void removevalues (FuncState *fs, int list) {
+ for (; list != NO_JUMP; list = getjump(fs, list))
+ patchtestreg(fs, list, NO_REG);
+}
+
+
+static void patchlistaux (FuncState *fs, int list, int vtarget, int reg,
+ int dtarget) {
+ while (list != NO_JUMP) {
+ int next = getjump(fs, list);
+ if (patchtestreg(fs, list, reg))
+ fixjump(fs, list, vtarget);
+ else
+ fixjump(fs, list, dtarget); /* jump to default target */
+ list = next;
+ }
+}
+
+
+static void dischargejpc (FuncState *fs) {
+ patchlistaux(fs, fs->jpc, 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);
+ patchlistaux(fs, list, target, NO_REG, target);
+ }
+}
+
+
+LUAI_FUNC void luaK_patchclose (FuncState *fs, int list, int level) {
+ level++; /* argument is +1 to reserve 0 as non-op */
+ while (list != NO_JUMP) {
+ int next = getjump(fs, list);
+ lua_assert(GET_OPCODE(fs->f->code[list]) == OP_JMP &&
+ (GETARG_A(fs->f->code[list]) == 0 ||
+ GETARG_A(fs->f->code[list]) >= level));
+ SETARG_A(fs->f->code[list], level);
+ list = next;
+ }
+}
+
+
+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 = getjump(fs, list)) != NO_JUMP) /* find last element */
+ list = next;
+ fixjump(fs, list, l2);
+ }
+}
+
+
+static int luaK_code (FuncState *fs, Instruction i) {
+ Proto *f = fs->f;
+ dischargejpc(fs); /* `pc' will change */
+ /* put new instruction in code array */
+ luaM_growvector(fs->ls->L, f->code, fs->pc, f->sizecode, Instruction,
+ MAX_INT, "opcodes");
+ f->code[fs->pc] = i;
+ /* save corresponding line information */
+ luaM_growvector(fs->ls->L, f->lineinfo, fs->pc, f->sizelineinfo, int,
+ MAX_INT, "opcodes");
+ f->lineinfo[fs->pc] = fs->ls->lastline;
+ return fs->pc++;
+}
+
+
+int luaK_codeABC (FuncState *fs, OpCode o, int a, int b, int c) {
+ lua_assert(getOpMode(o) == iABC);
+ lua_assert(getBMode(o) != OpArgN || b == 0);
+ lua_assert(getCMode(o) != OpArgN || c == 0);
+ lua_assert(a <= MAXARG_A && b <= MAXARG_B && c <= MAXARG_C);
+ return luaK_code(fs, CREATE_ABC(o, a, b, c));
+}
+
+
+int luaK_codeABx (FuncState *fs, OpCode o, int a, unsigned int bc) {
+ lua_assert(getOpMode(o) == iABx || getOpMode(o) == iAsBx);
+ lua_assert(getCMode(o) == OpArgN);
+ lua_assert(a <= MAXARG_A && bc <= MAXARG_Bx);
+ return luaK_code(fs, CREATE_ABx(o, a, bc));
+}
+
+
+static int codeextraarg (FuncState *fs, int a) {
+ lua_assert(a <= MAXARG_Ax);
+ return luaK_code(fs, CREATE_Ax(OP_EXTRAARG, a));
+}
+
+
+int luaK_codek (FuncState *fs, int reg, int k) {
+ if (k <= MAXARG_Bx)
+ return luaK_codeABx(fs, OP_LOADK, reg, k);
+ else {
+ int p = luaK_codeABx(fs, OP_LOADKX, reg, 0);
+ codeextraarg(fs, k);
+ return p;
+ }
+}
+
+
+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_byte(newstack);
+ }
+}
+
+
+void luaK_reserveregs (FuncState *fs, int n) {
+ luaK_checkstack(fs, n);
+ fs->freereg += n;
+}
+
+
+static void freereg (FuncState *fs, int reg) {
+ if (!ISK(reg) && reg >= fs->nactvar) {
+ fs->freereg--;
+ lua_assert(reg == fs->freereg);
+ }
+}
+
+
+static void freeexp (FuncState *fs, expdesc *e) {
+ if (e->k == VNONRELOC)
+ freereg(fs, e->u.info);
+}
+
+
+static int addk (FuncState *fs, TValue *key, TValue *v) {
+ lua_State *L = fs->ls->L;
+ TValue *idx = luaH_set(L, fs->h, key);
+ Proto *f = fs->f;
+ int k, oldsize;
+ if (ttisnumber(idx)) {
+ lua_Number n = nvalue(idx);
+ lua_number2int(k, n);
+ if (luaV_rawequalobj(&f->k[k], v))
+ return k;
+ /* else may be a collision (e.g., between 0.0 and "\0\0\0\0\0\0\0\0");
+ go through and create a new entry for this value */
+ }
+ /* constant not found; create a new entry */
+ oldsize = f->sizek;
+ k = fs->nk;
+ /* numerical value does not need GC barrier;
+ table has no metatable, so it does not need to invalidate cache */
+ setnvalue(idx, cast_num(k));
+ luaM_growvector(L, f->k, k, f->sizek, TValue, MAXARG_Ax, "constants");
+ while (oldsize < f->sizek) setnilvalue(&f->k[oldsize++]);
+ setobj(L, &f->k[k], v);
+ fs->nk++;
+ luaC_barrier(L, f, v);
+ return k;
+}
+
+
+int luaK_stringK (FuncState *fs, TString *s) {
+ TValue o;
+ setsvalue(fs->ls->L, &o, s);
+ return addk(fs, &o, &o);
+}
+
+
+int luaK_numberK (FuncState *fs, lua_Number r) {
+ int n;
+ lua_State *L = fs->ls->L;
+ TValue o;
+ setnvalue(&o, r);
+ if (r == 0 || luai_numisnan(NULL, r)) { /* handle -0 and NaN */
+ /* use raw representation as key to avoid numeric problems */
+ setsvalue(L, L->top++, luaS_newlstr(L, (char *)&r, sizeof(r)));
+ n = addk(fs, L->top - 1, &o);
+ L->top--;
+ }
+ else
+ n = addk(fs, &o, &o); /* regular case */
+ return n;
+}
+
+
+static int boolK (FuncState *fs, int b) {
+ TValue o;
+ setbvalue(&o, b);
+ return addk(fs, &o, &o);
+}
+
+
+static int nilK (FuncState *fs) {
+ TValue k, v;
+ setnilvalue(&v);
+ /* cannot use nil as key; instead use table itself to represent nil */
+ sethvalue(fs->ls->L, &k, fs->h);
+ return addk(fs, &k, &v);
+}
+
+
+void luaK_setreturns (FuncState *fs, expdesc *e, int nresults) {
+ if (e->k == VCALL) { /* expression is an open function call? */
+ SETARG_C(getcode(fs, e), nresults+1);
+ }
+ else if (e->k == VVARARG) {
+ SETARG_B(getcode(fs, e), nresults+1);
+ SETARG_A(getcode(fs, e), fs->freereg);
+ luaK_reserveregs(fs, 1);
+ }
+}
+
+
+void luaK_setoneret (FuncState *fs, expdesc *e) {
+ if (e->k == VCALL) { /* expression is an open function call? */
+ e->k = VNONRELOC;
+ e->u.info = GETARG_A(getcode(fs, e));
+ }
+ else if (e->k == VVARARG) {
+ SETARG_B(getcode(fs, e), 2);
+ e->k = VRELOCABLE; /* can relocate its simple result */
+ }
+}
+
+
+void luaK_dischargevars (FuncState *fs, expdesc *e) {
+ switch (e->k) {
+ case VLOCAL: {
+ e->k = VNONRELOC;
+ break;
+ }
+ case VUPVAL: {
+ e->u.info = luaK_codeABC(fs, OP_GETUPVAL, 0, e->u.info, 0);
+ e->k = VRELOCABLE;
+ break;
+ }
+ case VINDEXED: {
+ OpCode op = OP_GETTABUP; /* assume 't' is in an upvalue */
+ freereg(fs, e->u.ind.idx);
+ if (e->u.ind.vt == VLOCAL) { /* 't' is in a register? */
+ freereg(fs, e->u.ind.t);
+ op = OP_GETTABLE;
+ }
+ e->u.info = luaK_codeABC(fs, op, 0, e->u.ind.t, e->u.ind.idx);
+ e->k = VRELOCABLE;
+ break;
+ }
+ case VVARARG:
+ case VCALL: {
+ luaK_setoneret(fs, e);
+ 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_codek(fs, reg, e->u.info);
+ break;
+ }
+ case VKNUM: {
+ luaK_codek(fs, reg, luaK_numberK(fs, e->u.nval));
+ break;
+ }
+ case VRELOCABLE: {
+ Instruction *pc = &getcode(fs, e);
+ SETARG_A(*pc, reg);
+ break;
+ }
+ case VNONRELOC: {
+ if (reg != e->u.info)
+ luaK_codeABC(fs, OP_MOVE, reg, e->u.info, 0);
+ break;
+ }
+ default: {
+ lua_assert(e->k == VVOID || e->k == VJMP);
+ return; /* nothing to do... */
+ }
+ }
+ e->u.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 exp2reg (FuncState *fs, expdesc *e, int reg) {
+ discharge2reg(fs, e, reg);
+ if (e->k == VJMP)
+ luaK_concat(fs, &e->t, e->u.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) || need_value(fs, e->f)) {
+ int fj = (e->k == VJMP) ? NO_JUMP : 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);
+ patchlistaux(fs, e->f, final, reg, p_f);
+ patchlistaux(fs, e->t, final, reg, p_t);
+ }
+ e->f = e->t = NO_JUMP;
+ e->u.info = reg;
+ e->k = VNONRELOC;
+}
+
+
+void luaK_exp2nextreg (FuncState *fs, expdesc *e) {
+ luaK_dischargevars(fs, e);
+ freeexp(fs, e);
+ luaK_reserveregs(fs, 1);
+ 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->u.info; /* exp is already in a register */
+ if (e->u.info >= fs->nactvar) { /* reg. is not a local? */
+ exp2reg(fs, e, e->u.info); /* put value on it */
+ return e->u.info;
+ }
+ }
+ luaK_exp2nextreg(fs, e); /* default */
+ return e->u.info;
+}
+
+
+void luaK_exp2anyregup (FuncState *fs, expdesc *e) {
+ if (e->k != VUPVAL || hasjumps(e))
+ luaK_exp2anyreg(fs, e);
+}
+
+
+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 VTRUE:
+ case VFALSE:
+ case VNIL: {
+ if (fs->nk <= MAXINDEXRK) { /* constant fits in RK operand? */
+ e->u.info = (e->k == VNIL) ? nilK(fs) : boolK(fs, (e->k == VTRUE));
+ e->k = VK;
+ return RKASK(e->u.info);
+ }
+ else break;
+ }
+ case VKNUM: {
+ e->u.info = luaK_numberK(fs, e->u.nval);
+ e->k = VK;
+ /* go through */
+ }
+ case VK: {
+ if (e->u.info <= MAXINDEXRK) /* constant fits in argC? */
+ return RKASK(e->u.info);
+ 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 *ex) {
+ switch (var->k) {
+ case VLOCAL: {
+ freeexp(fs, ex);
+ exp2reg(fs, ex, var->u.info);
+ return;
+ }
+ case VUPVAL: {
+ int e = luaK_exp2anyreg(fs, ex);
+ luaK_codeABC(fs, OP_SETUPVAL, e, var->u.info, 0);
+ break;
+ }
+ case VINDEXED: {
+ OpCode op = (var->u.ind.vt == VLOCAL) ? OP_SETTABLE : OP_SETTABUP;
+ int e = luaK_exp2RK(fs, ex);
+ luaK_codeABC(fs, op, var->u.ind.t, var->u.ind.idx, e);
+ break;
+ }
+ default: {
+ lua_assert(0); /* invalid var kind to store */
+ break;
+ }
+ }
+ freeexp(fs, ex);
+}
+
+
+void luaK_self (FuncState *fs, expdesc *e, expdesc *key) {
+ int ereg;
+ luaK_exp2anyreg(fs, e);
+ ereg = e->u.info; /* register where 'e' was placed */
+ freeexp(fs, e);
+ e->u.info = fs->freereg; /* base register for op_self */
+ e->k = VNONRELOC;
+ luaK_reserveregs(fs, 2); /* function and 'self' produced by op_self */
+ luaK_codeABC(fs, OP_SELF, e->u.info, ereg, luaK_exp2RK(fs, key));
+ freeexp(fs, key);
+}
+
+
+static void invertjump (FuncState *fs, expdesc *e) {
+ Instruction *pc = getjumpcontrol(fs, e->u.info);
+ lua_assert(testTMode(GET_OPCODE(*pc)) && GET_OPCODE(*pc) != OP_TESTSET &&
+ 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 condjump(fs, OP_TEST, GETARG_B(ie), 0, !cond);
+ }
+ /* else go through */
+ }
+ discharge2anyreg(fs, e);
+ freeexp(fs, e);
+ return condjump(fs, OP_TESTSET, NO_REG, e->u.info, cond);
+}
+
+
+void luaK_goiftrue (FuncState *fs, expdesc *e) {
+ int pc; /* pc of last jump */
+ luaK_dischargevars(fs, e);
+ switch (e->k) {
+ case VJMP: {
+ invertjump(fs, e);
+ pc = e->u.info;
+ break;
+ }
+ case VK: case VKNUM: case VTRUE: {
+ pc = NO_JUMP; /* always true; do nothing */
+ break;
+ }
+ default: {
+ pc = jumponcond(fs, e, 0);
+ break;
+ }
+ }
+ luaK_concat(fs, &e->f, pc); /* insert last jump in `f' list */
+ luaK_patchtohere(fs, e->t);
+ e->t = NO_JUMP;
+}
+
+
+void luaK_goiffalse (FuncState *fs, expdesc *e) {
+ int pc; /* pc of last jump */
+ luaK_dischargevars(fs, e);
+ switch (e->k) {
+ case VJMP: {
+ pc = e->u.info;
+ break;
+ }
+ case VNIL: case VFALSE: {
+ pc = NO_JUMP; /* always false; do nothing */
+ break;
+ }
+ default: {
+ pc = jumponcond(fs, e, 1);
+ break;
+ }
+ }
+ luaK_concat(fs, &e->t, pc); /* insert last jump in `t' list */
+ luaK_patchtohere(fs, e->f);
+ e->f = NO_JUMP;
+}
+
+
+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 VKNUM: case VTRUE: {
+ e->k = VFALSE;
+ break;
+ }
+ case VJMP: {
+ invertjump(fs, e);
+ break;
+ }
+ case VRELOCABLE:
+ case VNONRELOC: {
+ discharge2anyreg(fs, e);
+ freeexp(fs, e);
+ e->u.info = luaK_codeABC(fs, OP_NOT, 0, e->u.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; }
+ removevalues(fs, e->f);
+ removevalues(fs, e->t);
+}
+
+
+void luaK_indexed (FuncState *fs, expdesc *t, expdesc *k) {
+ lua_assert(!hasjumps(t));
+ t->u.ind.t = t->u.info;
+ t->u.ind.idx = luaK_exp2RK(fs, k);
+ t->u.ind.vt = (t->k == VUPVAL) ? VUPVAL
+ : check_exp(vkisinreg(t->k), VLOCAL);
+ t->k = VINDEXED;
+}
+
+
+static int constfolding (OpCode op, expdesc *e1, expdesc *e2) {
+ lua_Number r;
+ if (!isnumeral(e1) || !isnumeral(e2)) return 0;
+ if ((op == OP_DIV || op == OP_MOD) && e2->u.nval == 0)
+ return 0; /* do not attempt to divide by 0 */
+ r = luaO_arith(op - OP_ADD + LUA_OPADD, e1->u.nval, e2->u.nval);
+ e1->u.nval = r;
+ return 1;
+}
+
+
+static void codearith (FuncState *fs, OpCode op,
+ expdesc *e1, expdesc *e2, int line) {
+ if (constfolding(op, e1, e2))
+ return;
+ else {
+ int o2 = (op != OP_UNM && op != OP_LEN) ? luaK_exp2RK(fs, e2) : 0;
+ int o1 = luaK_exp2RK(fs, e1);
+ if (o1 > o2) {
+ freeexp(fs, e1);
+ freeexp(fs, e2);
+ }
+ else {
+ freeexp(fs, e2);
+ freeexp(fs, e1);
+ }
+ e1->u.info = luaK_codeABC(fs, op, 0, o1, o2);
+ e1->k = VRELOCABLE;
+ luaK_fixline(fs, line);
+ }
+}
+
+
+static void codecomp (FuncState *fs, OpCode op, int cond, expdesc *e1,
+ expdesc *e2) {
+ int o1 = luaK_exp2RK(fs, e1);
+ int o2 = luaK_exp2RK(fs, e2);
+ freeexp(fs, e2);
+ freeexp(fs, e1);
+ if (cond == 0 && op != OP_EQ) {
+ int temp; /* exchange args to replace by `<' or `<=' */
+ temp = o1; o1 = o2; o2 = temp; /* o1 <==> o2 */
+ cond = 1;
+ }
+ e1->u.info = condjump(fs, op, cond, o1, o2);
+ e1->k = VJMP;
+}
+
+
+void luaK_prefix (FuncState *fs, UnOpr op, expdesc *e, int line) {
+ expdesc e2;
+ e2.t = e2.f = NO_JUMP; e2.k = VKNUM; e2.u.nval = 0;
+ switch (op) {
+ case OPR_MINUS: {
+ if (isnumeral(e)) /* minus constant? */
+ e->u.nval = luai_numunm(NULL, e->u.nval); /* fold it */
+ else {
+ luaK_exp2anyreg(fs, e);
+ codearith(fs, OP_UNM, e, &e2, line);
+ }
+ break;
+ }
+ case OPR_NOT: codenot(fs, e); break;
+ case OPR_LEN: {
+ luaK_exp2anyreg(fs, e); /* cannot operate on constants */
+ codearith(fs, OP_LEN, e, &e2, line);
+ break;
+ }
+ default: lua_assert(0);
+ }
+}
+
+
+void luaK_infix (FuncState *fs, BinOpr op, expdesc *v) {
+ switch (op) {
+ case OPR_AND: {
+ luaK_goiftrue(fs, v);
+ break;
+ }
+ case OPR_OR: {
+ luaK_goiffalse(fs, v);
+ break;
+ }
+ case OPR_CONCAT: {
+ luaK_exp2nextreg(fs, v); /* operand must be on the `stack' */
+ break;
+ }
+ case OPR_ADD: case OPR_SUB: case OPR_MUL: case OPR_DIV:
+ case OPR_MOD: case OPR_POW: {
+ if (!isnumeral(v)) luaK_exp2RK(fs, v);
+ break;
+ }
+ default: {
+ luaK_exp2RK(fs, v);
+ break;
+ }
+ }
+}
+
+
+void luaK_posfix (FuncState *fs, BinOpr op,
+ expdesc *e1, expdesc *e2, int line) {
+ switch (op) {
+ case OPR_AND: {
+ lua_assert(e1->t == NO_JUMP); /* list must be closed */
+ luaK_dischargevars(fs, e2);
+ luaK_concat(fs, &e2->f, e1->f);
+ *e1 = *e2;
+ break;
+ }
+ case OPR_OR: {
+ lua_assert(e1->f == NO_JUMP); /* list must be closed */
+ luaK_dischargevars(fs, e2);
+ luaK_concat(fs, &e2->t, e1->t);
+ *e1 = *e2;
+ break;
+ }
+ case OPR_CONCAT: {
+ luaK_exp2val(fs, e2);
+ if (e2->k == VRELOCABLE && GET_OPCODE(getcode(fs, e2)) == OP_CONCAT) {
+ lua_assert(e1->u.info == GETARG_B(getcode(fs, e2))-1);
+ freeexp(fs, e1);
+ SETARG_B(getcode(fs, e2), e1->u.info);
+ e1->k = VRELOCABLE; e1->u.info = e2->u.info;
+ }
+ else {
+ luaK_exp2nextreg(fs, e2); /* operand must be on the 'stack' */
+ codearith(fs, OP_CONCAT, e1, e2, line);
+ }
+ break;
+ }
+ case OPR_ADD: case OPR_SUB: case OPR_MUL: case OPR_DIV:
+ case OPR_MOD: case OPR_POW: {
+ codearith(fs, cast(OpCode, op - OPR_ADD + OP_ADD), e1, e2, line);
+ break;
+ }
+ case OPR_EQ: case OPR_LT: case OPR_LE: {
+ codecomp(fs, cast(OpCode, op - OPR_EQ + OP_EQ), 1, e1, e2);
+ break;
+ }
+ case OPR_NE: case OPR_GT: case OPR_GE: {
+ codecomp(fs, cast(OpCode, op - OPR_NE + OP_EQ), 0, e1, e2);
+ break;
+ }
+ default: lua_assert(0);
+ }
+}
+
+
+void luaK_fixline (FuncState *fs, int line) {
+ fs->f->lineinfo[fs->pc - 1] = line;
+}
+
+
+void luaK_setlist (FuncState *fs, int base, int nelems, int tostore) {
+ int c = (nelems - 1)/LFIELDS_PER_FLUSH + 1;
+ int b = (tostore == LUA_MULTRET) ? 0 : tostore;
+ lua_assert(tostore != 0);
+ if (c <= MAXARG_C)
+ luaK_codeABC(fs, OP_SETLIST, base, b, c);
+ else if (c <= MAXARG_Ax) {
+ luaK_codeABC(fs, OP_SETLIST, base, b, 0);
+ codeextraarg(fs, c);
+ }
+ else
+ luaX_syntaxerror(fs->ls, "constructor too long");
+ fs->freereg = base + 1; /* free registers with list values */
+}
+
projects / proxmark3-svn / blobdiff