This file implements transforms for initial VPlan construction. More...

#include "LoopVectorizationPlanner.h"
#include "VPlan.h"
#include "VPlanCFG.h"
#include "VPlanDominatorTree.h"
#include "VPlanPatternMatch.h"
#include "VPlanTransforms.h"
#include "llvm/Analysis/LoopInfo.h"
#include "llvm/Analysis/LoopIterator.h"
#include "llvm/Analysis/ScalarEvolution.h"
#include "llvm/Analysis/ScalarEvolutionExpressions.h"
#include "llvm/IR/InstrTypes.h"
#include "llvm/IR/MDBuilder.h"
#include "llvm/Transforms/Utils/LoopUtils.h"
#include "llvm/Transforms/Utils/LoopVersioning.h"

Macros
#define	DEBUG_TYPE "vplan"

Functions
static bool	isHeaderBB (BasicBlock BB, Loop L)
static bool	canonicalHeaderAndLatch (VPBlockBase *HeaderVPB, const VPDominatorTree &VPDT)
	Checks if `HeaderVPB` is a loop header block in the plain CFG; that is, it has exactly 2 predecessors (preheader and latch), where the block dominates the latch and the preheader dominates the block.
static void	createLoopRegion (VPlan &Plan, VPBlockBase *HeaderVPB)
	Create a new VPRegionBlock for the loop starting at `HeaderVPB`.
static void	addCanonicalIVRecipes (VPlan &Plan, VPBasicBlock HeaderVPBB, VPBasicBlock LatchVPBB, Type *IdxTy, DebugLoc DL)
static void	createExtractsForLiveOuts (VPlan &Plan, VPBasicBlock *MiddleVPBB)
	Creates extracts for values in `Plan` defined in a loop region and used outside a loop region.
static void	addInitialSkeleton (VPlan &Plan, Type InductionTy, DebugLoc IVDL, PredicatedScalarEvolution &PSE, Loop TheLoop)
static void	simplifyLiveInsWithSCEV (VPlan &Plan, ScalarEvolution &SE)
	Check `Plan's` live-in and replace them with constants, if they can be simplified via SCEV.
static VPHeaderPHIRecipe *	createWidenInductionRecipe (PHINode Phi, VPPhi PhiR, VPValue *Start, const InductionDescriptor &IndDesc, VPlan &Plan, ScalarEvolution &SE, Loop &OrigLoop, DebugLoc DL)
	Creates a VPWidenIntOrFpInductionRecipe or VPWidenPointerInductionRecipe for `Phi` based on `IndDesc`.
template<typename MatchT>
static VPRecipeBase *	findUserOf (VPValue *V, const MatchT &P)
	If `V` is used by a recipe matching pattern `P`, return it.
template<unsigned Opcode>
static VPInstruction *	findUserOf (VPValue *V)
	If `V` is used by a VPInstruction with `Opcode`, return it.

Variables
static constexpr uint32_t	CheckBypassWeights [] = {1, 127}

Detailed Description

This file implements transforms for initial VPlan construction.

Definition in file VPlanConstruction.cpp.

Macro Definition Documentation

◆ DEBUG_TYPE

#define DEBUG_TYPE "vplan"

Definition at line 29 of file VPlanConstruction.cpp.

Function Documentation

◆ addCanonicalIVRecipes()

void addCanonicalIVRecipes	(	VPlan &	Plan,
		VPBasicBlock *	HeaderVPBB,
		VPBasicBlock *	LatchVPBB,
		Type *	IdxTy,
		DebugLoc	DL )

static

Definition at line 452 of file VPlanConstruction.cpp.

References llvm::VPBasicBlock::back(), llvm::VPBasicBlock::begin(), llvm::VPInstruction::BranchOnCount, DL, llvm::VPBasicBlock::empty(), llvm::VPRecipeBase::eraseFromParent(), llvm::VPRecipeBase::getDebugLoc(), llvm::VPlan::getOrAddLiveIn(), llvm::VPBasicBlock::getTerminator(), llvm::VPlan::getVectorTripCount(), llvm::VPlan::getVFxUF(), llvm::VPBasicBlock::insert(), llvm::VPlanPatternMatch::m_BranchOnCond(), and llvm::PatternMatch::match().

Referenced by addInitialSkeleton().

◆ addInitialSkeleton()

void addInitialSkeleton	(	VPlan &	Plan,
		Type *	InductionTy,
		DebugLoc	IVDL,
		PredicatedScalarEvolution &	PSE,
		Loop *	TheLoop )

static

Definition at line 509 of file VPlanConstruction.cpp.

References addCanonicalIVRecipes(), llvm::VPUser::addOperand(), assert(), canonicalHeaderAndLatch(), llvm::cast(), llvm::VPBlockUtils::connectBlocks(), createExtractsForLiveOuts(), llvm::VPBuilder::createScalarPhi(), llvm::VPlan::createVPBasicBlock(), llvm::drop_begin(), llvm::VPlan::getEntry(), llvm::vputils::getOrCreateVPValueForSCEVExpr(), llvm::VPlan::getScalarHeader(), llvm::PredicatedScalarEvolution::getSE(), llvm::VPBlockBase::getSingleSuccessor(), llvm::VPBlockBase::getSuccessors(), llvm::PredicatedScalarEvolution::getSymbolicMaxBackedgeTakenCount(), llvm::ScalarEvolution::getTripCountFromExitCount(), llvm::VPBlockUtils::insertBlockAfter(), llvm::VPBlockUtils::insertOnEdge(), llvm::isa(), llvm::VPBasicBlock::phis(), llvm::VPlan::setTripCount(), llvm::VPBlockBase::swapSuccessors(), and llvm::zip_equal().

Referenced by llvm::VPlanTransforms::buildVPlan0().

◆ canonicalHeaderAndLatch()

bool canonicalHeaderAndLatch	(	VPBlockBase *	HeaderVPB,
		const VPDominatorTree &	VPDT )

static

Checks if HeaderVPB is a loop header block in the plain CFG; that is, it has exactly 2 predecessors (preheader and latch), where the block dominates the latch and the preheader dominates the block.

If it is a header block return true and canonicalize the predecessors of the header (making sure the preheader appears first and the latch second) and the successors of the latch (making sure the loop exit comes first). Otherwise return false.

Definition at line 378 of file VPlanConstruction.cpp.

References assert(), llvm::VPInstruction::BranchOnCond, llvm::cast(), llvm::DominatorTreeBase< NodeT, IsPostDom >::dominates(), getOpcode(), llvm::VPBlockBase::getPredecessors(), llvm::VPInstruction::Not, llvm::ArrayRef< T >::size(), std::swap(), and llvm::VPBlockBase::swapPredecessors().

Referenced by addInitialSkeleton(), and llvm::VPlanTransforms::createLoopRegions().

◆ createExtractsForLiveOuts()

void createExtractsForLiveOuts	(	VPlan &	Plan,
		VPBasicBlock *	MiddleVPBB )

static

Creates extracts for values in Plan defined in a loop region and used outside a loop region.

Definition at line 487 of file VPlanConstruction.cpp.

References assert(), B(), llvm::cast(), llvm::VPlan::getExitBlocks(), and llvm::VPBasicBlock::getFirstNonPhi().

Referenced by addInitialSkeleton().

◆ createLoopRegion()

void createLoopRegion	(	VPlan &	Plan,
		VPBlockBase *	HeaderVPB )

static

Create a new VPRegionBlock for the loop starting at HeaderVPB.

Definition at line 425 of file VPlanConstruction.cpp.

References assert(), llvm::VPBlockUtils::connectBlocks(), llvm::VPlan::createLoopRegion(), llvm::VPBlockUtils::disconnectBlocks(), llvm::VPBlockBase::getPredecessors(), llvm::VPBlockBase::getSingleSuccessor(), llvm::VPBlockUtils::insertOnEdge(), llvm::VPBlockBase::setParent(), and llvm::vp_depth_first_shallow().

Referenced by llvm::VPlanTransforms::createLoopRegions().

◆ createWidenInductionRecipe()

VPHeaderPHIRecipe * createWidenInductionRecipe	(	PHINode *	Phi,
		VPPhi *	PhiR,
		VPValue *	Start,
		const InductionDescriptor &	IndDesc,
		VPlan &	Plan,
		ScalarEvolution &	SE,
		Loop &	OrigLoop,
		DebugLoc	DL )