steam-frame/FEX-Emu--FEX
1
0 Fork 0
mirror of https://github.com/FEX-Emu/FEX.git synced 2026-10-06 21:00:17 +02:00
Code Issues Packages Projects Releases 66 Wiki Activity

OpcodeDispatcher: remove bfe for small shl imm

Browse Source 
We allow the garbage in flags calculation, it's ignored.

Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
This commit is contained in:
Alyssa Rosenzweig committed 2023-11-13 21:21:01 -04:00
1 parent 282ed3e309
commit 0f25a960ee
2 files changed
+4 -8
Download Patch File Download Diff File Expand all files Collapse all files

No files matched your search

FEXCore/Source/Interface/Core/OpcodeDispatcher.cpp
-4
View File
@@ -1679,10 +1679,6 @@ void OpDispatchBuilder::SHLImmediateOp(OpcodeArgs) {
StoreResult(GPRClass, Op, Result, -1);
if (Size < 32) {
Result = _Bfe(OpSize::i32Bit, Size, 0, Result);
}
GenerateFlags_ShiftLeftImmediate(Op, Result, Dest, Shift);
}
FEXCore/Source/Interface/Core/OpcodeDispatcher/Flags.cpp
+4 -4
View File
@@ -806,13 +806,13 @@ void OpDispatchBuilder::CalculateFlags_SignShiftRight(uint8_t SrcSize, OrderedNo
PossiblySetNZCVBits |= OldSetNZCVBits;
}
void OpDispatchBuilder::CalculateFlags_ShiftLeftImmediate(uint8_t SrcSize, OrderedNode *Res, OrderedNode *Src1, uint64_t Shift) {
void OpDispatchBuilder::CalculateFlags_ShiftLeftImmediate(uint8_t SrcSize, OrderedNode *UnmaskedRes, OrderedNode *Src1, uint64_t Shift) {
// No flags changed if shift is zero
if (Shift == 0) return;
auto OpSize = SrcSize == 8 ? OpSize::i64Bit : OpSize::i32Bit;
SetNZ_ZeroCV(SrcSize, Res);
SetNZ_ZeroCV(SrcSize, UnmaskedRes);
// CF
{
@@ -824,7 +824,7 @@ void OpDispatchBuilder::CalculateFlags_ShiftLeftImmediate(uint8_t SrcSize, Order
SetRFLAG<FEXCore::X86State::RFLAG_CF_RAW_LOC>(Src1, SrcSizeBits - Shift, true);
}
CalculatePF(Res);
CalculatePF(UnmaskedRes);
// AF
// Undefined
@@ -833,7 +833,7 @@ void OpDispatchBuilder::CalculateFlags_ShiftLeftImmediate(uint8_t SrcSize, Order
// OF
// In the case of left shift. OF is only set from the result of <Top Source Bit> XOR <Top Result Bit>
if (Shift == 1) {
auto Xor = _Xor(OpSize, Res, Src1);
auto Xor = _Xor(OpSize, UnmaskedRes, Src1);
SetRFLAG<FEXCore::X86State::RFLAG_OF_RAW_LOC>(Xor, SrcSize * 8 - 1, true);
} else {
// Undefined, we choose to zero as part of SetNZ_ZeroCV