FEX-Emu/FEX
1
0
Fork 0
mirror of https://github.com/FEX-Emu/FEX.git synced 2024-12-15 01:49:00 +00:00
Code Issues Actions 6 Packages Projects Releases Wiki Activity

OpcodeDispatcher: add SetAFAndFixup helper

Browse Source 
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
This commit is contained in:
Alyssa Rosenzweig 2024-03-25 12:59:19 -04:00
parent ea4fce7a43
commit 693d86dd67
2 changed files with 14 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
FEXCore/Source/Interface/Core/OpcodeDispatcher.h
View File

@ -1764,6 +1764,7 @@ private:
OrderedNode *LoadPFRaw();
OrderedNode *LoadAF();
void FixupAF();
void SetAFAndFixup(OrderedNode *AF);
void CalculatePF(OrderedNode *Res);
void CalculateAF(OrderedNode *Src1, OrderedNode *Src2);

13
FEXCore/Source/Interface/Core/OpcodeDispatcher/Flags.cpp
View File

@ -277,6 +277,19 @@ void OpDispatchBuilder::FixupAF() {
SetRFLAG<FEXCore::X86State::RFLAG_AF_RAW_LOC>(XorRes);
}
void OpDispatchBuilder::SetAFAndFixup(OrderedNode *AF) {
// We have a value of AF, we shift into AF[4]. We need to fixup AF[4] so that
// we get the right value when we XOR in PF[4] later. The easiest solution is
// to XOR by PF[4], since:
//
// (AF[4] ^ PF[4]) ^ PF[4] = AF[4]
auto PFRaw = GetRFLAG(FEXCore::X86State::RFLAG_PF_RAW_LOC);
OrderedNode *XorRes = _XorShift(OpSize::i32Bit, PFRaw, AF, ShiftType::LSL, 4);
SetRFLAG<FEXCore::X86State::RFLAG_AF_RAW_LOC>(XorRes);
}
void OpDispatchBuilder::CalculatePF(OrderedNode *Res) {
// Calculation is entirely deferred until load, just store the 8-bit result.
SetRFLAG<FEXCore::X86State::RFLAG_PF_RAW_LOC>(Res);