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RegAllocGreedy: Remove redundant check for virtual registers
ClosedPublic

Authored by arsenm on Mar 28 2022, 6:14 AM.

Reviewers

qcolombet
MatzeB

Summary

The set of interfering virtual registers obviously only includes
virtual registers.

	Time	Test
	60,050 ms	x64 debian > libFuzzer.libFuzzer::large.test

arsenm requested review of this revision.Mar 28 2022, 6:14 AM

ping

This revision is now accepted and ready to land.Apr 13 2022, 11:23 AM

Path

Size

llvm/

lib/

CodeGen/

3 lines

Show First 20 Lines • Show All 455 Lines • ▼ Show 20 Lines	for (MCRegUnitIterator Units(PhysReg, TRI); Units.isValid(); ++Units) {
LiveIntervalUnion::Query &Q = Matrix->query(VirtReg, *Units);		LiveIntervalUnion::Query &Q = Matrix->query(VirtReg, *Units);

// Check if any interfering live range is heavier than MaxWeight.		// Check if any interfering live range is heavier than MaxWeight.
for (const LiveInterval *Intf : reverse(Q.interferingVRegs())) {		for (const LiveInterval *Intf : reverse(Q.interferingVRegs())) {
// Check if interference overlast the segment in interest.		// Check if interference overlast the segment in interest.
if (!Intf->overlaps(Start, End))		if (!Intf->overlaps(Start, End))
continue;		continue;

// Cannot evict non virtual reg interference.
if (!Register::isVirtualRegister(Intf->reg()))
return false;
// Never evict spill products. They cannot split or spill.		// Never evict spill products. They cannot split or spill.
if (ExtraInfo->getStage(*Intf) == RS_Done)		if (ExtraInfo->getStage(*Intf) == RS_Done)
return false;		return false;

// Would this break a satisfied hint?		// Would this break a satisfied hint?
bool BreaksHint = VRM->hasPreferredPhys(Intf->reg());		bool BreaksHint = VRM->hasPreferredPhys(Intf->reg());
// Update eviction cost.		// Update eviction cost.
Cost.BrokenHints += BreaksHint;		Cost.BrokenHints += BreaksHint;
▲ Show 20 Lines • Show All 2,235 Lines • Show Last 20 Lines