diff --git a/lcode.c b/lcode.c index ccc7d2b9..13d12a13 100644 --- a/lcode.c +++ b/lcode.c @@ -1,5 +1,5 @@ /* -** $Id: lcode.c,v 2.103 2015/11/19 19:16:22 roberto Exp roberto $ +** $Id: lcode.c,v 2.104 2015/12/17 14:52:53 roberto Exp roberto $ ** Code generator for Lua ** See Copyright Notice in lua.h */ @@ -73,6 +73,39 @@ void luaK_nil (FuncState *fs, int from, int n) { } +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 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); +} + + +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); + } +} + + int luaK_jump (FuncState *fs) { int jpc = fs->jpc; /* save list of jumps to here */ int j; @@ -94,16 +127,6 @@ static int condjump (FuncState *fs, OpCode op, int A, int B, int C) { } -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). @@ -114,15 +137,6 @@ int luaK_getlabel (FuncState *fs) { } -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)))) @@ -132,19 +146,6 @@ static Instruction *getjumpcontrol (FuncState *fs, int pc) { } -/* -** 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) @@ -183,6 +184,12 @@ static void dischargejpc (FuncState *fs) { } +void luaK_patchtohere (FuncState *fs, int list) { + luaK_getlabel(fs); + luaK_concat(fs, &fs->jpc, list); +} + + void luaK_patchlist (FuncState *fs, int list, int target) { if (target == fs->pc) luaK_patchtohere(fs, list); @@ -204,26 +211,6 @@ void luaK_patchclose (FuncState *fs, int list, int level) { } -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 */ @@ -434,12 +421,6 @@ void luaK_dischargevars (FuncState *fs, expdesc *e) { } -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) { @@ -491,6 +472,25 @@ static void discharge2anyreg (FuncState *fs, expdesc *e) { } +static int code_loadbool (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); +} + + +/* +** 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 void exp2reg (FuncState *fs, expdesc *e, int reg) { discharge2reg(fs, e, reg); if (e->k == VJMP) @@ -501,8 +501,8 @@ static void exp2reg (FuncState *fs, expdesc *e, int reg) { 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); + p_f = code_loadbool(fs, reg, 0, 1); + p_t = code_loadbool(fs, reg, 1, 0); luaK_patchtohere(fs, fj); } final = luaK_getlabel(fs);