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Minor fix to SHL op to not update flags if the shift amount was zero.

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Ryan Houdek authored and Stefanos Kornilios Mitsis Poiitidis committed 2020-03-06 07:52:32 +02:00
1 parent f503bd573f
commit 46f983fbb6
2 files changed
+50 -1
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Source/Interface/Core/OpcodeDispatcher.cpp
+49 -1
View File
@@ -1156,7 +1156,7 @@ void OpDispatchBuilder::SHLOp(OpcodeArgs) {
StoreResult(Op, ALUOp);
// XXX: This isn't correct
GenerateFlags_Logical(Op, _Bfe(Size, 0, ALUOp), _Bfe(Size, 0, Dest), _Bfe(Size, 0, Src));
GenerateFlags_Shift(Op, _Bfe(Size, 0, ALUOp), _Bfe(Size, 0, Dest), _Bfe(Size, 0, Src));
}
void OpDispatchBuilder::SHROp(OpcodeArgs) {
@@ -2904,6 +2904,54 @@ void OpDispatchBuilder::GenerateFlags_Logical(FEXCore::X86Tables::DecodedOp Op,
SetRFLAG<FEXCore::X86State::RFLAG_OF_LOC>(ZeroConst);
}
}
void OpDispatchBuilder::GenerateFlags_Shift(FEXCore::X86Tables::DecodedOp Op, OrderedNode *Res, OrderedNode *Src1, OrderedNode *Src2) {
auto ZeroConst = _Constant(0);
auto OneConst = _Constant(1);
auto CmpResult = _Select(FEXCore::IR::COND_EQ, Src2, ZeroConst, OneConst, ZeroConst);
auto CondJump = _CondJump(CmpResult);
// AF
{
// Undefined
// Set to zero anyway
SetRFLAG<FEXCore::X86State::RFLAG_AF_LOC>(ZeroConst);
}
// SF
{
auto SignBitConst = _Constant(GetSrcSize(Op) * 8 - 1);
auto LshrOp = _Lshr(Res, SignBitConst);
SetRFLAG<FEXCore::X86State::RFLAG_SF_LOC>(LshrOp);
}
// PF
{
auto EightBitMask = _Constant(0xFF);
auto PopCountOp = _Popcount(_And(Res, EightBitMask));
auto XorOp = _Xor(PopCountOp, OneConst);
SetRFLAG<FEXCore::X86State::RFLAG_PF_LOC>(XorOp);
}
// ZF
{
auto SelectOp = _Select(FEXCore::IR::COND_EQ,
Res, ZeroConst, OneConst, ZeroConst);
SetRFLAG<FEXCore::X86State::RFLAG_ZF_LOC>(SelectOp);
}
// CF/OF
{
SetRFLAG<FEXCore::X86State::RFLAG_CF_LOC>(ZeroConst);
SetRFLAG<FEXCore::X86State::RFLAG_OF_LOC>(ZeroConst);
}
_EndBlock(0);
auto NewBlock = _BeginBlock();
SetJumpTarget(CondJump, NewBlock);
}
void OpDispatchBuilder::GenerateFlags_Rotate(FEXCore::X86Tables::DecodedOp Op, OrderedNode *Res, OrderedNode *Src1, OrderedNode *Src2) {
auto ZeroConst = _Constant(0);
Source/Interface/Core/OpcodeDispatcher.h
+1
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@@ -294,6 +294,7 @@ private:
void GenerateFlags_MUL(FEXCore::X86Tables::DecodedOp Op, OrderedNode *Res, OrderedNode *High);
void GenerateFlags_UMUL(FEXCore::X86Tables::DecodedOp Op, OrderedNode *High);
void GenerateFlags_Logical(FEXCore::X86Tables::DecodedOp Op, OrderedNode *Res, OrderedNode *Src1, OrderedNode *Src2);
void GenerateFlags_Shift(FEXCore::X86Tables::DecodedOp Op, OrderedNode *Res, OrderedNode *Src1, OrderedNode *Src2);
void GenerateFlags_Rotate(FEXCore::X86Tables::DecodedOp Op, OrderedNode *Res, OrderedNode *Src1, OrderedNode *Src2);
OrderedNode *CreateNode(IROp_Header *Op) {