1 //===-- VPlanHCFGTransforms.cpp - Utility VPlan to VPlan transforms -------===//
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7 //===----------------------------------------------------------------------===//
10 /// This file implements a set of utility VPlan to VPlan transformations.
12 //===----------------------------------------------------------------------===//
14 #include "VPlanHCFGTransforms.h"
15 #include "llvm/ADT/PostOrderIterator.h"
19 void VPlanHCFGTransforms::VPInstructionsToVPRecipes(
21 LoopVectorizationLegality::InductionList *Inductions,
22 SmallPtrSetImpl<Instruction *> &DeadInstructions) {
24 VPRegionBlock *TopRegion = dyn_cast<VPRegionBlock>(Plan->getEntry());
25 ReversePostOrderTraversal<VPBlockBase *> RPOT(TopRegion->getEntry());
27 // Condition bit VPValues get deleted during transformation to VPRecipes.
28 // Create new VPValues and save away as condition bits. These will be deleted
29 // after finalizing the vector IR basic blocks.
30 for (VPBlockBase *Base : RPOT) {
31 VPBasicBlock *VPBB = Base->getEntryBasicBlock();
32 if (auto *CondBit = VPBB->getCondBit()) {
33 auto *NCondBit = new VPValue(CondBit->getUnderlyingValue());
34 VPBB->setCondBit(NCondBit);
35 Plan->addCBV(NCondBit);
38 for (VPBlockBase *Base : RPOT) {
39 // Do not widen instructions in pre-header and exit blocks.
40 if (Base->getNumPredecessors() == 0 || Base->getNumSuccessors() == 0)
43 VPBasicBlock *VPBB = Base->getEntryBasicBlock();
44 VPRecipeBase *LastRecipe = nullptr;
45 // Introduce each ingredient into VPlan.
46 for (auto I = VPBB->begin(), E = VPBB->end(); I != E;) {
47 VPRecipeBase *Ingredient = &*I++;
48 // Can only handle VPInstructions.
49 VPInstruction *VPInst = cast<VPInstruction>(Ingredient);
50 Instruction *Inst = cast<Instruction>(VPInst->getUnderlyingValue());
51 if (DeadInstructions.count(Inst)) {
52 Ingredient->eraseFromParent();
56 VPRecipeBase *NewRecipe = nullptr;
57 // Create VPWidenMemoryInstructionRecipe for loads and stores.
58 if (isa<LoadInst>(Inst) || isa<StoreInst>(Inst))
59 NewRecipe = new VPWidenMemoryInstructionRecipe(*Inst, nullptr /*Mask*/);
60 else if (PHINode *Phi = dyn_cast<PHINode>(Inst)) {
61 InductionDescriptor II = Inductions->lookup(Phi);
62 if (II.getKind() == InductionDescriptor::IK_IntInduction ||
63 II.getKind() == InductionDescriptor::IK_FpInduction) {
64 NewRecipe = new VPWidenIntOrFpInductionRecipe(Phi);
66 NewRecipe = new VPWidenPHIRecipe(Phi);
68 // If the last recipe is a VPWidenRecipe, add Inst to it instead of
69 // creating a new recipe.
70 if (VPWidenRecipe *WidenRecipe =
71 dyn_cast_or_null<VPWidenRecipe>(LastRecipe)) {
72 WidenRecipe->appendInstruction(Inst);
73 Ingredient->eraseFromParent();
76 NewRecipe = new VPWidenRecipe(Inst);
79 NewRecipe->insertBefore(Ingredient);
80 LastRecipe = NewRecipe;
81 Ingredient->eraseFromParent();