commit b55fded18c270412e127259a5f28c785620dbf1a
parent 2dadc8182282afa4b1fe6e6287704a54cd8e5123
Author: Roberto Ierusalimschy <roberto@inf.puc-rio.br>
Date: Mon, 13 May 2002 10:07:26 -0300
details about jump optimization
Diffstat:
2 files changed, 24 insertions(+), 14 deletions(-)
diff --git a/lcode.c b/lcode.c
@@ -1,5 +1,5 @@
/*
-** $Id: lcode.c,v 1.101 2002/05/10 17:02:32 roberto Exp roberto $
+** $Id: lcode.c,v 1.102 2002/05/10 19:22:11 roberto Exp roberto $
** Code generator for Lua
** See Copyright Notice in lua.h
*/
@@ -75,12 +75,6 @@ int luaK_getlabel (FuncState *fs) {
}
-void luaK_dischargejpc (FuncState *fs) {
- luaK_patchlist(fs, fs->jpc, fs->pc); /* discharge old list `jpc' */
- fs->jpc = NO_JUMP;
-}
-
-
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 */
@@ -144,9 +138,19 @@ static void luaK_patchlistaux (FuncState *fs, int list,
}
+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) {
- lua_assert(target <= fs->pc);
- luaK_patchlistaux(fs, list, target, NO_REG, target, NO_REG, 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);
+ }
}
@@ -342,12 +346,12 @@ static void luaK_exp2reg (FuncState *fs, expdesc *e, int reg) {
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)) {
- if (e->k != VJMP) {
- luaK_getlabel(fs); /* this instruction may be a jump target */
- luaK_codeAsBx(fs, OP_JMP, 0, 2); /* to jump over both pushes */
- }
+ 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);
@@ -724,6 +728,11 @@ void luaK_posfix (FuncState *fs, BinOpr op, expdesc *e1, expdesc *e2) {
}
+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;
int oldsize = f->sizecode;
diff --git a/lcode.h b/lcode.h
@@ -1,5 +1,5 @@
/*
-** $Id: lcode.h,v 1.34 2002/05/10 17:02:32 roberto Exp roberto $
+** $Id: lcode.h,v 1.35 2002/05/10 19:22:11 roberto Exp $
** Code generator for Lua
** See Copyright Notice in lua.h
*/
@@ -44,6 +44,7 @@ typedef enum UnOpr { OPR_MINUS, OPR_NOT, OPR_NOUNOPR } UnOpr;
int luaK_code (FuncState *fs, Instruction i, int line);
int luaK_codeABx (FuncState *fs, OpCode o, int A, unsigned int Bx);
int luaK_codeABC (FuncState *fs, OpCode o, int A, int B, int C);
+void luaK_fixline (FuncState *fs, int line);
void luaK_nil (FuncState *fs, int from, int n);
void luaK_reserveregs (FuncState *fs, int n);
int luaK_stringK (FuncState *fs, TString *s);