1 //===- VPlanTransforms.h - Utility VPlan to VPlan transforms --------------===// 2 // 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 6 // 7 //===----------------------------------------------------------------------===// 8 /// 9 /// \file 10 /// This file provides utility VPlan to VPlan transformations. 11 //===----------------------------------------------------------------------===// 12 13 #ifndef LLVM_TRANSFORMS_VECTORIZE_VPLANTRANSFORMS_H 14 #define LLVM_TRANSFORMS_VECTORIZE_VPLANTRANSFORMS_H 15 16 #include "VPlan.h" 17 #include "llvm/ADT/STLFunctionalExtras.h" 18 19 namespace llvm { 20 21 class InductionDescriptor; 22 class Instruction; 23 class PHINode; 24 class ScalarEvolution; 25 class Loop; 26 class PredicatedScalarEvolution; 27 class TargetLibraryInfo; 28 29 struct VPlanTransforms { 30 /// Replaces the VPInstructions in \p Plan with corresponding 31 /// widen recipes. 32 static void 33 VPInstructionsToVPRecipes(Loop *OrigLoop, VPlanPtr &Plan, 34 function_ref<const InductionDescriptor *(PHINode *)> 35 GetIntOrFpInductionDescriptor, 36 SmallPtrSetImpl<Instruction *> &DeadInstructions, 37 ScalarEvolution &SE, const TargetLibraryInfo &TLI); 38 39 static bool sinkScalarOperands(VPlan &Plan); 40 41 /// Merge replicate regions in their successor region, if a replicate region 42 /// is connected to a successor replicate region with the same predicate by a 43 /// single, empty VPBasicBlock. 44 static bool mergeReplicateRegionsIntoSuccessors(VPlan &Plan); 45 46 /// Remove redundant VPBasicBlocks by merging them into their predecessor if 47 /// the predecessor has a single successor. 48 static bool mergeBlocksIntoPredecessors(VPlan &Plan); 49 50 /// Remove redundant casts of inductions. 51 /// 52 /// Such redundant casts are casts of induction variables that can be ignored, 53 /// because we already proved that the casted phi is equal to the uncasted phi 54 /// in the vectorized loop. There is no need to vectorize the cast - the same 55 /// value can be used for both the phi and casts in the vector loop. 56 static void removeRedundantInductionCasts(VPlan &Plan); 57 58 /// Try to replace VPWidenCanonicalIVRecipes with a widened canonical IV 59 /// recipe, if it exists. 60 static void removeRedundantCanonicalIVs(VPlan &Plan); 61 62 static void removeDeadRecipes(VPlan &Plan); 63 64 /// If any user of a VPWidenIntOrFpInductionRecipe needs scalar values, 65 /// provide them by building scalar steps off of the canonical scalar IV and 66 /// update the original IV's users. This is an optional optimization to reduce 67 /// the needs of vector extracts. 68 static void optimizeInductions(VPlan &Plan, ScalarEvolution &SE); 69 70 /// Remove redundant EpxandSCEVRecipes in \p Plan's entry block by replacing 71 /// them with already existing recipes expanding the same SCEV expression. 72 static void removeRedundantExpandSCEVRecipes(VPlan &Plan); 73 74 /// Optimize \p Plan based on \p BestVF and \p BestUF. This may restrict the 75 /// resulting plan to \p BestVF and \p BestUF. 76 static void optimizeForVFAndUF(VPlan &Plan, ElementCount BestVF, 77 unsigned BestUF, 78 PredicatedScalarEvolution &PSE); 79 }; 80 81 } // namespace llvm 82 83 #endif // LLVM_TRANSFORMS_VECTORIZE_VPLANTRANSFORMS_H 84