Merge pull request #7414 from Sintendo/shortmovs

x64Emitter: emit shorter MOVs for 64-bit immediates
This commit is contained in:
Tilka
2018-10-06 00:01:35 +01:00
committed by GitHub
2 changed files with 64 additions and 18 deletions

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@ -1469,11 +1469,21 @@ void OpArg::WriteNormalOp(XEmitter* emit, bool toRM, NormalOp op, const OpArg& o
// mov reg64, imm64
else if (op == NormalOp::MOV)
{
emit->Write8(0xB8 + (offsetOrBaseReg & 7));
emit->Write64((u64)operand.offset);
return;
// movabs reg64, imm64 (10 bytes)
if (static_cast<s64>(operand.offset) != static_cast<s32>(operand.offset))
{
emit->Write8(0xB8 + (offsetOrBaseReg & 7));
emit->Write64(operand.offset);
return;
}
// mov reg64, simm32 (7 bytes)
emit->Write8(op_def.imm32);
immToWrite = 32;
}
else
{
ASSERT_MSG(DYNA_REC, 0, "WriteNormalOp - Only MOV can take 64-bit imm");
}
ASSERT_MSG(DYNA_REC, 0, "WriteNormalOp - Only MOV can take 64-bit imm");
}
else
{
@ -1581,6 +1591,12 @@ void XEmitter::XOR(int bits, const OpArg& a1, const OpArg& a2)
}
void XEmitter::MOV(int bits, const OpArg& a1, const OpArg& a2)
{
if (bits == 64 && a1.IsSimpleReg() && a2.scale == SCALE_IMM64 &&
a2.offset == static_cast<u32>(a2.offset))
{
WriteNormalOp(32, NormalOp::MOV, a1, a2.AsImm32());
return;
}
if (a1.IsSimpleReg() && a2.IsSimpleReg() && a1.GetSimpleReg() == a2.GetSimpleReg())
ERROR_LOG(DYNA_REC, "Redundant MOV @ %p - bug in JIT?", code);
WriteNormalOp(bits, NormalOp::MOV, a1, a2);