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

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
commit a42d849ec1
Notes: sideshowbarker 2024-07-17 10:31:19 +09:00

View file

@ -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);