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LibJIT: Widen allowed argument range for add32 and use REX if necessary

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The REX prefix is elided when it is not needed, so no change in code
size is to be expected
This commit is contained in:
Hendiadyoin1 2023-10-29 14:47:44 +01:00 • committed by Andreas Kling
parent 248782461c
commit a42d849ec1
1 changed files with 6 additions and 3 deletions
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9
Userland/Libraries/LibJIT/Assembler.h
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@ -615,14 +615,17 @@ struct Assembler {
void add32(Operand dst, Operand src, Optional<Label&> label)
{
if (dst.type == Operand::Type::Reg && to_underlying(dst.reg) < 8 && src.type == Operand::Type::Reg && to_underlying(src.reg) < 8) {
if (dst.is_register_or_memory() && src.type == Operand::Type::Reg) {
emit_rex_for_mr(dst, src, REX_W::No);
emit8(0x01);
emit_modrm_mr(dst, src);
} else if (dst.type == Operand::Type::Reg && to_underlying(dst.reg) < 8 && src.type == Operand::Type::Imm && src.fits_in_i8()) {
} else if (dst.is_register_or_memory() && src.type == Operand::Type::Imm && src.fits_in_i8()) {
emit_rex_for_slash(dst, REX_W::No);
emit8(0x83);
emit_modrm_slash(0, dst);
emit8(src.offset_or_immediate);
} else if (dst.type == Operand::Type::Reg && to_underlying(dst.reg) < 8 && src.type == Operand::Type::Imm && src.fits_in_i32()) {
} else if (dst.is_register_or_memory() && src.type == Operand::Type::Imm && src.fits_in_i32()) {
emit_rex_for_slash(dst, REX_W::No);
emit8(0x81);
emit_modrm_slash(0, dst);
emit32(src.offset_or_immediate);