contrib/llvm-project/llvm/include/llvm/Transforms/IPO/HotColdSplitting.h

   1 //===- HotColdSplitting.h ---- Outline Cold Regions -------------*- C++ -*-===//
   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 // This pass outlines cold regions to a separate function.
   9 //
  10 //===----------------------------------------------------------------------===//
  11
  12 #ifndef LLVM_TRANSFORMS_IPO_HOTCOLDSPLITTING_H
  13 #define LLVM_TRANSFORMS_IPO_HOTCOLDSPLITTING_H
  14
  15 #include "llvm/IR/PassManager.h"
  16
  17 namespace llvm {
  18
  19 class Module;
  20 class ProfileSummaryInfo;
  21 class BlockFrequencyInfo;
  22 class TargetTransformInfo;
  23 class OptimizationRemarkEmitter;
  24 class AssumptionCache;
  25 class DominatorTree;
  26 class CodeExtractorAnalysisCache;
  27
  28 /// A sequence of basic blocks.
  29 ///
  30 /// A 0-sized SmallVector is slightly cheaper to move than a std::vector.
  31 using BlockSequence = SmallVector<BasicBlock *, 0>;
  32
  33 class HotColdSplitting {
  34 public:
  35   HotColdSplitting(ProfileSummaryInfo *ProfSI,
  36                    function_ref<BlockFrequencyInfo *(Function &)> GBFI,
  37                    function_ref<TargetTransformInfo &(Function &)> GTTI,
  38                    std::function<OptimizationRemarkEmitter &(Function &)> *GORE,
  39                    function_ref<AssumptionCache *(Function &)> LAC)
  40       : PSI(ProfSI), GetBFI(GBFI), GetTTI(GTTI), GetORE(GORE), LookupAC(LAC) {}
  41   bool run(Module &M);
  42
  43 private:
  44   bool isFunctionCold(const Function &F) const;
  45   bool shouldOutlineFrom(const Function &F) const;
  46   bool outlineColdRegions(Function &F, bool HasProfileSummary);
  47   Function *extractColdRegion(const BlockSequence &Region,
  48                               const CodeExtractorAnalysisCache &CEAC,
  49                               DominatorTree &DT, BlockFrequencyInfo *BFI,
  50                               TargetTransformInfo &TTI,
  51                               OptimizationRemarkEmitter &ORE,
  52                               AssumptionCache *AC, unsigned Count);
  53   ProfileSummaryInfo *PSI;
  54   function_ref<BlockFrequencyInfo *(Function &)> GetBFI;
  55   function_ref<TargetTransformInfo &(Function &)> GetTTI;
  56   std::function<OptimizationRemarkEmitter &(Function &)> *GetORE;
  57   function_ref<AssumptionCache *(Function &)> LookupAC;
  58 };
  59
  60 /// Pass to outline cold regions.
  61 class HotColdSplittingPass : public PassInfoMixin<HotColdSplittingPass> {
  62 public:
  63   PreservedAnalyses run(Module &M, ModuleAnalysisManager &AM);
  64 };
  65
  66 } // end namespace llvm
  67
  68 #endif // LLVM_TRANSFORMS_IPO_HOTCOLDSPLITTING_H
  69