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Differential D63673

AMDGPU: Cleanup checking when spills need emergency slots
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Authored by arsenm on Jun 21 2019, 2:53 PM.

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rampitec

Summary

Address fixme, which should no longer be a problem since r363757.

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Event Timeline

arsenm created this revision.Jun 21 2019, 2:53 PM

Herald added subscribers: t-tye, tpr, dstuttard and 5 others. · View Herald TranscriptJun 21 2019, 2:53 PM

LGTM

This revision is now accepted and ready to land.Jun 21 2019, 7:10 PM

r364182

Revision Contents

Path

Size

lib/

Target/

AMDGPU/

SIFrameLowering.cpp

13 lines

Diff 206085

lib/Target/AMDGPU/SIFrameLowering.cpp

Show First 20 Lines • Show All 715 Lines • ▼ Show 20 Lines	if (RoundedSize != 0 && hasFP(MF)) {
const unsigned StackPtrReg = FuncInfo->getStackPtrOffsetReg();		const unsigned StackPtrReg = FuncInfo->getStackPtrOffsetReg();
BuildMI(MBB, MBBI, DL, TII->get(AMDGPU::S_SUB_U32), StackPtrReg)		BuildMI(MBB, MBBI, DL, TII->get(AMDGPU::S_SUB_U32), StackPtrReg)
.addReg(StackPtrReg)		.addReg(StackPtrReg)
.addImm(RoundedSize * ST.getWavefrontSize())		.addImm(RoundedSize * ST.getWavefrontSize())
.setMIFlag(MachineInstr::FrameDestroy);		.setMIFlag(MachineInstr::FrameDestroy);
}		}
}		}

static bool allStackObjectsAreDead(const MachineFrameInfo &MFI) {		// Note SGPRSpill stack IDs should only be used for SGPR spilling to VGPRs, not
		// memory.
		static bool allStackObjectsAreDeadOrSGPR(const MachineFrameInfo &MFI) {
for (int I = MFI.getObjectIndexBegin(), E = MFI.getObjectIndexEnd();		for (int I = MFI.getObjectIndexBegin(), E = MFI.getObjectIndexEnd();
I != E; ++I) {		I != E; ++I) {
if (!MFI.isDeadObjectIndex(I))		if (!MFI.isDeadObjectIndex(I) &&
		MFI.getStackID(I) != TargetStackID::SGPRSpill)
return false;		return false;
}		}

return true;		return true;
}		}

int SIFrameLowering::getFrameIndexReference(const MachineFunction &MF, int FI,		int SIFrameLowering::getFrameIndexReference(const MachineFunction &MF, int FI,
unsigned &FrameReg) const {		unsigned &FrameReg) const {
▲ Show 20 Lines • Show All 45 Lines • ▼ Show 20 Lines	for (MachineBasicBlock &MBB : MF) {
AllSGPRSpilledToVGPRs = false;		AllSGPRSpilledToVGPRs = false;
}		}
}		}
}		}
}		}

FuncInfo->removeSGPRToVGPRFrameIndices(MFI);		FuncInfo->removeSGPRToVGPRFrameIndices(MFI);

// FIXME: The other checks should be redundant with allStackObjectsAreDead,		if (!allStackObjectsAreDeadOrSGPR(MFI)) {
// but currently hasNonSpillStackObjects is set only from source
// allocas. Stack temps produced from legalization are not counted currently.
if (FuncInfo->hasNonSpillStackObjects() \|\| FuncInfo->hasSpilledVGPRs() \|\|
!AllSGPRSpilledToVGPRs \|\| !allStackObjectsAreDead(MFI)) {
assert(RS && "RegScavenger required if spilling");		assert(RS && "RegScavenger required if spilling");

if (FuncInfo->isEntryFunction()) {		if (FuncInfo->isEntryFunction()) {
int ScavengeFI = MFI.CreateFixedObject(		int ScavengeFI = MFI.CreateFixedObject(
TRI.getSpillSize(AMDGPU::SGPR_32RegClass), 0, false);		TRI.getSpillSize(AMDGPU::SGPR_32RegClass), 0, false);
RS->addScavengingFrameIndex(ScavengeFI);		RS->addScavengingFrameIndex(ScavengeFI);
} else {		} else {
int ScavengeFI = MFI.CreateStackObject(		int ScavengeFI = MFI.CreateStackObject(
▲ Show 20 Lines • Show All 71 Lines • Show Last 20 Lines