GCNRewritePartialRegUses.cpp File Reference

RenameIndependentSubregs pass leaves large partially used super registers, for example: undef %0.sub4:VReg_1024 = ... %0.sub5:VReg_1024 = ... %0.sub6:VReg_1024 = ... %0.sub7:VReg_1024 = ... use %0.sub4_sub5_sub6_sub7 use %0.sub6_sub7. More...

#include "AMDGPU.h"
#include "MCTargetDesc/AMDGPUMCTargetDesc.h"
#include "SIRegisterInfo.h"
#include "llvm/CodeGen/LiveInterval.h"
#include "llvm/CodeGen/LiveIntervals.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/TargetInstrInfo.h"
#include "llvm/InitializePasses.h"
#include "llvm/Pass.h"

Go to the source code of this file.

Macros
#define	DEBUG_TYPE   "rewrite-partial-reg-uses"

Functions
	INITIALIZE_PASS_BEGIN (GCNRewritePartialRegUses, DEBUG_TYPE, "Rewrite Partial Register Uses", false, false) INITIALIZE_PASS_END(GCNRewritePartialRegUses

Variables
	DEBUG_TYPE
Rewrite Partial Register	Uses
Rewrite Partial Register	false

Detailed Description

RenameIndependentSubregs pass leaves large partially used super registers, for example: undef %0.sub4:VReg_1024 = ... %0.sub5:VReg_1024 = ... %0.sub6:VReg_1024 = ... %0.sub7:VReg_1024 = ... use %0.sub4_sub5_sub6_sub7 use %0.sub6_sub7.

GCNRewritePartialRegUses goes right after RenameIndependentSubregs and rewrites such partially used super registers with registers of minimal size: undef %0.sub0:VReg_128 = ... %0.sub1:VReg_128 = ... %0.sub2:VReg_128 = ... %0.sub3:VReg_128 = ... use %0.sub0_sub1_sub2_sub3 use %0.sub2_sub3

This allows to avoid subreg lanemasks tracking during register pressure calculation and creates more possibilities for the code unaware of lanemasks

Definition in file GCNRewritePartialRegUses.cpp.

Macro Definition Documentation

DEBUG_TYPE

#define DEBUG_TYPE   "rewrite-partial-reg-uses"

Definition at line 45 of file GCNRewritePartialRegUses.cpp.

Function Documentation

INITIALIZE_PASS_BEGIN()

INITIALIZE_PASS_BEGIN	(	GCNRewritePartialRegUses	,
		DEBUG_TYPE	,
		"Rewrite Partial Register Uses"	,
		false	,
		false
	)

Variable Documentation

DEBUG_TYPE

DEBUG_TYPE

Definition at line 499 of file GCNRewritePartialRegUses.cpp.

false

Rewrite Partial Register false

Definition at line 500 of file GCNRewritePartialRegUses.cpp.

Uses

Rewrite Partial Register Uses

Definition at line 500 of file GCNRewritePartialRegUses.cpp.

Referenced by addArgumentAttrs(), allUsesOfLoadAndStores(), llvm::CombinerHelper::applyCombineExtendingLoads(), llvm::Attributor::checkForAllCallSites(), ClearKillFlags(), collectAllocaUses(), llvm::ReachingDefAnalysis::collectKilledOperands(), computeLiveOuts(), llvm::rdf::Liveness::computePhiInfo(), llvm::PeelingModuloScheduleExpander::CreateLCSSAExitingBlock(), llvm::OpenMPIRBuilder::createParallel(), llvm::HexagonRegisterInfo::eliminateFrameIndex(), llvm::LegalizerHelper::fewerElementsVectorMultiEltType(), llvm::X86RegisterInfo::findDeadCallerSavedReg(), findDeadCallerSavedReg(), findHoistingInsertPosAndDeps(), findUses(), llvm::rdf::Liveness::getAllReachedUses(), llvm::ReachingDefAnalysis::getGlobalUses(), llvm::ReachingDefAnalysis::getLiveInUses(), llvm::ReachingDefAnalysis::getReachingLocalUses(), llvm::mca::InstructionBase::getUses(), llvm::ReachingDefAnalysis::isSafeToDefRegAt(), parseOperands(), llvm::PeelSingleBlockLoop(), propagateLocalCopies(), relocationViaAlloca(), llvm::removeAllNonTerminatorAndEHPadInstructions(), llvm::SelectionDAG::ReplaceAllUsesOfValuesWith(), llvm::ReplaceableMetadataImpl::replaceAllUsesWith(), llvm::ReplaceableMetadataImpl::resolveAllUses(), llvm::ReplaceableMetadataImpl::SalvageDebugInfo(), TrackDefUses(), and UpdateSSA().