1 //===- LoopVectorize.h ------------------------------------------*- C++ -*-===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // This is the LLVM loop vectorizer. This pass modifies 'vectorizable' loops 11 // and generates target-independent LLVM-IR. 12 // The vectorizer uses the TargetTransformInfo analysis to estimate the costs 13 // of instructions in order to estimate the profitability of vectorization. 14 // 15 // The loop vectorizer combines consecutive loop iterations into a single 16 // 'wide' iteration. After this transformation the index is incremented 17 // by the SIMD vector width, and not by one. 18 // 19 // This pass has three parts: 20 // 1. The main loop pass that drives the different parts. 21 // 2. LoopVectorizationLegality - A unit that checks for the legality 22 // of the vectorization. 23 // 3. InnerLoopVectorizer - A unit that performs the actual 24 // widening of instructions. 25 // 4. LoopVectorizationCostModel - A unit that checks for the profitability 26 // of vectorization. It decides on the optimal vector width, which 27 // can be one, if vectorization is not profitable. 28 // 29 //===----------------------------------------------------------------------===// 30 // 31 // The reduction-variable vectorization is based on the paper: 32 // D. Nuzman and R. Henderson. Multi-platform Auto-vectorization. 33 // 34 // Variable uniformity checks are inspired by: 35 // Karrenberg, R. and Hack, S. Whole Function Vectorization. 36 // 37 // The interleaved access vectorization is based on the paper: 38 // Dorit Nuzman, Ira Rosen and Ayal Zaks. Auto-Vectorization of Interleaved 39 // Data for SIMD 40 // 41 // Other ideas/concepts are from: 42 // A. Zaks and D. Nuzman. Autovectorization in GCC-two years later. 43 // 44 // S. Maleki, Y. Gao, M. Garzaran, T. Wong and D. Padua. An Evaluation of 45 // Vectorizing Compilers. 46 // 47 //===----------------------------------------------------------------------===// 48 49 #ifndef LLVM_TRANSFORMS_VECTORIZE_LOOPVECTORIZE_H 50 #define LLVM_TRANSFORMS_VECTORIZE_LOOPVECTORIZE_H 51 52 #include "llvm/Analysis/AliasAnalysis.h" 53 #include "llvm/IR/PassManager.h" 54 #include <functional> 55 56 namespace llvm { 57 58 class AssumptionCache; 59 class BlockFrequencyInfo; 60 class DemandedBits; 61 class DominatorTree; 62 class Function; 63 class Loop; 64 class LoopAccessInfo; 65 class LoopInfo; 66 class OptimizationRemarkEmitter; 67 class ScalarEvolution; 68 class TargetLibraryInfo; 69 class TargetTransformInfo; 70 71 /// The LoopVectorize Pass. 72 struct LoopVectorizePass : public PassInfoMixin<LoopVectorizePass> { 73 bool DisableUnrolling = false; 74 75 /// If true, consider all loops for vectorization. 76 /// If false, only loops that explicitly request vectorization are 77 /// considered. 78 bool AlwaysVectorize = true; 79 80 ScalarEvolution *SE; 81 LoopInfo *LI; 82 TargetTransformInfo *TTI; 83 DominatorTree *DT; 84 BlockFrequencyInfo *BFI; 85 TargetLibraryInfo *TLI; 86 DemandedBits *DB; 87 AliasAnalysis *AA; 88 AssumptionCache *AC; 89 std::function<const LoopAccessInfo &(Loop &)> *GetLAA; 90 OptimizationRemarkEmitter *ORE; 91 92 PreservedAnalyses run(Function &F, FunctionAnalysisManager &AM); 93 94 // Shim for old PM. 95 bool runImpl(Function &F, ScalarEvolution &SE_, LoopInfo &LI_, 96 TargetTransformInfo &TTI_, DominatorTree &DT_, 97 BlockFrequencyInfo &BFI_, TargetLibraryInfo *TLI_, 98 DemandedBits &DB_, AliasAnalysis &AA_, AssumptionCache &AC_, 99 std::function<const LoopAccessInfo &(Loop &)> &GetLAA_, 100 OptimizationRemarkEmitter &ORE); 101 102 bool processLoop(Loop *L); 103 }; 104 105 } // end namespace llvm 106 107 #endif // LLVM_TRANSFORMS_VECTORIZE_LOOPVECTORIZE_H 108
