1 //===- llvm/IR/ProfDataUtils.h - Profiling Metadata Utilities ---*- 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 // 9 /// @file 10 /// This file contains the declarations for profiling metadata utility 11 /// functions. 12 // 13 //===----------------------------------------------------------------------===// 14 15 #ifndef LLVM_IR_PROFDATAUTILS_H 16 #define LLVM_IR_PROFDATAUTILS_H 17 18 #include "llvm/ADT/SmallVector.h" 19 #include "llvm/ADT/Twine.h" 20 #include "llvm/IR/Metadata.h" 21 22 namespace llvm { 23 24 /// Checks if an Instruction has MD_prof Metadata 25 bool hasProfMD(const Instruction &I); 26 27 /// Checks if an MDNode contains Branch Weight Metadata 28 bool isBranchWeightMD(const MDNode *ProfileData); 29 30 /// Checks if an instructions has Branch Weight Metadata 31 /// 32 /// \param I The instruction to check 33 /// \returns True if I has an MD_prof node containing Branch Weights. False 34 /// otherwise. 35 bool hasBranchWeightMD(const Instruction &I); 36 37 /// Checks if an instructions has valid Branch Weight Metadata 38 /// 39 /// \param I The instruction to check 40 /// \returns True if I has an MD_prof node containing valid Branch Weights, 41 /// i.e., one weight for each successor. False otherwise. 42 bool hasValidBranchWeightMD(const Instruction &I); 43 44 /// Get the branch weights metadata node 45 /// 46 /// \param I The Instruction to get the weights from. 47 /// \returns A pointer to I's branch weights metadata node, if it exists. 48 /// Nullptr otherwise. 49 MDNode *getBranchWeightMDNode(const Instruction &I); 50 51 /// Get the valid branch weights metadata node 52 /// 53 /// \param I The Instruction to get the weights from. 54 /// \returns A pointer to I's valid branch weights metadata node, if it exists. 55 /// Nullptr otherwise. 56 MDNode *getValidBranchWeightMDNode(const Instruction &I); 57 58 /// Extract branch weights from MD_prof metadata 59 /// 60 /// \param ProfileData A pointer to an MDNode. 61 /// \param [out] Weights An output vector to fill with branch weights 62 /// \returns True if weights were extracted, False otherwise. When false Weights 63 /// will be cleared. 64 bool extractBranchWeights(const MDNode *ProfileData, 65 SmallVectorImpl<uint32_t> &Weights); 66 67 /// Faster version of extractBranchWeights() that skips checks and must only 68 /// be called with "branch_weights" metadata nodes. 69 void extractFromBranchWeightMD(const MDNode *ProfileData, 70 SmallVectorImpl<uint32_t> &Weights); 71 72 /// Extract branch weights attatched to an Instruction 73 /// 74 /// \param I The Instruction to extract weights from. 75 /// \param [out] Weights An output vector to fill with branch weights 76 /// \returns True if weights were extracted, False otherwise. When false Weights 77 /// will be cleared. 78 bool extractBranchWeights(const Instruction &I, 79 SmallVectorImpl<uint32_t> &Weights); 80 81 /// Extract branch weights from a conditional branch or select Instruction. 82 /// 83 /// \param I The instruction to extract branch weights from. 84 /// \param [out] TrueVal will contain the branch weight for the True branch 85 /// \param [out] FalseVal will contain the branch weight for the False branch 86 /// \returns True on success with profile weights filled in. False if no 87 /// metadata or invalid metadata was found. 88 bool extractBranchWeights(const Instruction &I, uint64_t &TrueVal, 89 uint64_t &FalseVal); 90 91 /// Retrieve the total of all weights from MD_prof data. 92 /// 93 /// \param ProfileData The profile data to extract the total weight from 94 /// \param [out] TotalWeights input variable to fill with total weights 95 /// \returns True on success with profile total weights filled in. False if no 96 /// metadata was found. 97 bool extractProfTotalWeight(const MDNode *ProfileData, uint64_t &TotalWeights); 98 99 /// Retrieve the total of all weights from an instruction. 100 /// 101 /// \param I The instruction to extract the total weight from 102 /// \param [out] TotalWeights input variable to fill with total weights 103 /// \returns True on success with profile total weights filled in. False if no 104 /// metadata was found. 105 bool extractProfTotalWeight(const Instruction &I, uint64_t &TotalWeights); 106 107 /// Create a new `branch_weights` metadata node and add or overwrite 108 /// a `prof` metadata reference to instruction `I`. 109 void setBranchWeights(Instruction &I, ArrayRef<uint32_t> Weights); 110 111 } // namespace llvm 112 #endif 113