llvm-project/llvm/lib/Transforms/Vectorize/VPlanTransforms.cpp
David Green d0d38df091 [LoopVectorizer] Change types of lists from pointers to references. NFC
getReductionVars, getInductionVars and getFirstOrderRecurrences were all
being returned from LoopVectorizationLegality as pointers to lists. This
just changes them to be references, cleaning up the interface slightly.

Differential Revision: https://reviews.llvm.org/D75448
2020-03-02 15:04:41 +00:00

89 lines
3.4 KiB
C++

//===-- VPlanTransforms.cpp - Utility VPlan to VPlan transforms -----------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
///
/// \file
/// This file implements a set of utility VPlan to VPlan transformations.
///
//===----------------------------------------------------------------------===//
#include "VPlanTransforms.h"
#include "llvm/ADT/PostOrderIterator.h"
using namespace llvm;
void VPlanTransforms::VPInstructionsToVPRecipes(
Loop *OrigLoop, VPlanPtr &Plan,
LoopVectorizationLegality::InductionList &Inductions,
SmallPtrSetImpl<Instruction *> &DeadInstructions) {
auto *TopRegion = cast<VPRegionBlock>(Plan->getEntry());
ReversePostOrderTraversal<VPBlockBase *> RPOT(TopRegion->getEntry());
// Condition bit VPValues get deleted during transformation to VPRecipes.
// Create new VPValues and save away as condition bits. These will be deleted
// after finalizing the vector IR basic blocks.
for (VPBlockBase *Base : RPOT) {
VPBasicBlock *VPBB = Base->getEntryBasicBlock();
if (auto *CondBit = VPBB->getCondBit()) {
auto *NCondBit = new VPValue(CondBit->getUnderlyingValue());
VPBB->setCondBit(NCondBit);
Plan->addCBV(NCondBit);
}
}
for (VPBlockBase *Base : RPOT) {
// Do not widen instructions in pre-header and exit blocks.
if (Base->getNumPredecessors() == 0 || Base->getNumSuccessors() == 0)
continue;
VPBasicBlock *VPBB = Base->getEntryBasicBlock();
VPRecipeBase *LastRecipe = nullptr;
// Introduce each ingredient into VPlan.
for (auto I = VPBB->begin(), E = VPBB->end(); I != E;) {
VPRecipeBase *Ingredient = &*I++;
// Can only handle VPInstructions.
VPInstruction *VPInst = cast<VPInstruction>(Ingredient);
Instruction *Inst = cast<Instruction>(VPInst->getUnderlyingValue());
if (DeadInstructions.count(Inst)) {
Ingredient->eraseFromParent();
continue;
}
VPRecipeBase *NewRecipe = nullptr;
// Create VPWidenMemoryInstructionRecipe for loads and stores.
if (isa<LoadInst>(Inst) || isa<StoreInst>(Inst))
NewRecipe = new VPWidenMemoryInstructionRecipe(
*Inst, Plan->getOrAddVPValue(getLoadStorePointerOperand(Inst)),
nullptr /*Mask*/);
else if (PHINode *Phi = dyn_cast<PHINode>(Inst)) {
InductionDescriptor II = Inductions.lookup(Phi);
if (II.getKind() == InductionDescriptor::IK_IntInduction ||
II.getKind() == InductionDescriptor::IK_FpInduction) {
NewRecipe = new VPWidenIntOrFpInductionRecipe(Phi);
} else
NewRecipe = new VPWidenPHIRecipe(Phi);
} else if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(Inst)) {
NewRecipe = new VPWidenGEPRecipe(GEP, OrigLoop);
} else {
// If the last recipe is a VPWidenRecipe, add Inst to it instead of
// creating a new recipe.
if (VPWidenRecipe *WidenRecipe =
dyn_cast_or_null<VPWidenRecipe>(LastRecipe)) {
WidenRecipe->appendInstruction(Inst);
Ingredient->eraseFromParent();
continue;
}
NewRecipe = new VPWidenRecipe(Inst);
}
NewRecipe->insertBefore(Ingredient);
LastRecipe = NewRecipe;
Ingredient->eraseFromParent();
}
}
}