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Removed arithmetic opcodes with immediate operand

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The difference in performance between immediate operands and K operands
does not seem to justify all those extra opcodes. We only keep OP_ADDI,
due to its ubiquity and because the difference is a little more relevant.
(Later, OP_SUBI will be implemented by OP_ADDI, negating the constant.)
This commit is contained in:
Roberto Ierusalimschy
2019-09-10 13:20:03 -03:00
parent 4518e5df24
commit 91dad09f65
7 changed files with 17 additions and 65 deletions
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16
lcode.c
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@@ -1342,7 +1342,7 @@ static void finishbinexpval (FuncState *fs, expdesc *e1, expdesc *e2,
OpCode op, int v2, int flip, int line,
OpCode mmop, TMS event) {
int v1 = luaK_exp2anyreg(fs, e1);
int pc = luaK_codeABCk(fs, op, 0, v1, v2, flip);
int pc = luaK_codeABCk(fs, op, 0, v1, v2, 0);
freeexps(fs, e1, e2);
e1->u.info = pc;
e1->k = VRELOC; /* all those operations are relocatable */
@@ -1372,7 +1372,7 @@ static void codebinexpval (FuncState *fs, OpCode op,
/*
** Code binary operators ('+', '-', ...) with immediate operands.
** Code binary operators with immediate operands.
*/
static void codebini (FuncState *fs, OpCode op,
expdesc *e1, expdesc *e2, int flip, int line,
@@ -1389,15 +1389,12 @@ static void swapexps (expdesc *e1, expdesc *e2) {
/*
** Code arithmetic operators ('+', '-', ...). If second operand is a
** constant in the proper range, use variant opcodes with immediate
** operands or K operands.
** constant in the proper range, use variant opcodes with K operands.
*/
static void codearith (FuncState *fs, BinOpr opr,
expdesc *e1, expdesc *e2, int flip, int line) {
TMS event = cast(TMS, opr + TM_ADD);
if (isSCint(e2)) /* immediate operand? */
codebini(fs, cast(OpCode, opr + OP_ADDI), e1, e2, flip, line, event);
else if (tonumeral(e2, NULL) && luaK_exp2K(fs, e2)) { /* K operand? */
if (tonumeral(e2, NULL) && luaK_exp2K(fs, e2)) { /* K operand? */
int v2 = e2->u.info; /* K index */
OpCode op = cast(OpCode, opr + OP_ADDK);
finishbinexpval(fs, e1, e2, op, v2, flip, line, OP_MMBINK, event);
@@ -1423,7 +1420,10 @@ static void codecommutative (FuncState *fs, BinOpr op,
swapexps(e1, e2); /* change order */
flip = 1;
}
codearith(fs, op, e1, e2, flip, line);
if (op == OPR_ADD && isSCint(e2)) /* immediate operand? */
codebini(fs, cast(OpCode, OP_ADDI), e1, e2, flip, line, TM_ADD);
else
codearith(fs, op, e1, e2, flip, line);
}