1 //===- CodeGen/Analysis.h - CodeGen LLVM IR Analysis 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 // This file declares several CodeGen-specific LLVM IR analysis utilities. 10 // 11 //===----------------------------------------------------------------------===// 12 13 #ifndef LLVM_CODEGEN_ANALYSIS_H 14 #define LLVM_CODEGEN_ANALYSIS_H 15 16 #include "llvm/ADT/ArrayRef.h" 17 #include "llvm/ADT/DenseMap.h" 18 #include "llvm/CodeGen/ISDOpcodes.h" 19 #include "llvm/IR/Instructions.h" 20 21 namespace llvm { 22 template <typename T> class SmallVectorImpl; 23 class GlobalValue; 24 class LLT; 25 class MachineBasicBlock; 26 class MachineFunction; 27 class TargetLoweringBase; 28 class TargetLowering; 29 class TargetMachine; 30 struct EVT; 31 32 /// Compute the linearized index of a member in a nested 33 /// aggregate/struct/array. 34 /// 35 /// Given an LLVM IR aggregate type and a sequence of insertvalue or 36 /// extractvalue indices that identify a member, return the linearized index of 37 /// the start of the member, i.e the number of element in memory before the 38 /// sought one. This is disconnected from the number of bytes. 39 /// 40 /// \param Ty is the type indexed by \p Indices. 41 /// \param Indices is an optional pointer in the indices list to the current 42 /// index. 43 /// \param IndicesEnd is the end of the indices list. 44 /// \param CurIndex is the current index in the recursion. 45 /// 46 /// \returns \p CurIndex plus the linear index in \p Ty the indices list. 47 unsigned ComputeLinearIndex(Type *Ty, 48 const unsigned *Indices, 49 const unsigned *IndicesEnd, 50 unsigned CurIndex = 0); 51 52 inline unsigned ComputeLinearIndex(Type *Ty, 53 ArrayRef<unsigned> Indices, 54 unsigned CurIndex = 0) { 55 return ComputeLinearIndex(Ty, Indices.begin(), Indices.end(), CurIndex); 56 } 57 58 /// ComputeValueVTs - Given an LLVM IR type, compute a sequence of 59 /// EVTs that represent all the individual underlying 60 /// non-aggregate types that comprise it. 61 /// 62 /// If Offsets is non-null, it points to a vector to be filled in 63 /// with the in-memory offsets of each of the individual values. 64 /// 65 void ComputeValueVTs(const TargetLowering &TLI, const DataLayout &DL, Type *Ty, 66 SmallVectorImpl<EVT> &ValueVTs, 67 SmallVectorImpl<uint64_t> *Offsets = nullptr, 68 uint64_t StartingOffset = 0); 69 70 /// Variant of ComputeValueVTs that also produces the memory VTs. 71 void ComputeValueVTs(const TargetLowering &TLI, const DataLayout &DL, Type *Ty, 72 SmallVectorImpl<EVT> &ValueVTs, 73 SmallVectorImpl<EVT> *MemVTs, 74 SmallVectorImpl<uint64_t> *Offsets = nullptr, 75 uint64_t StartingOffset = 0); 76 77 /// computeValueLLTs - Given an LLVM IR type, compute a sequence of 78 /// LLTs that represent all the individual underlying 79 /// non-aggregate types that comprise it. 80 /// 81 /// If Offsets is non-null, it points to a vector to be filled in 82 /// with the in-memory offsets of each of the individual values. 83 /// 84 void computeValueLLTs(const DataLayout &DL, Type &Ty, 85 SmallVectorImpl<LLT> &ValueTys, 86 SmallVectorImpl<uint64_t> *Offsets = nullptr, 87 uint64_t StartingOffset = 0); 88 89 /// ExtractTypeInfo - Returns the type info, possibly bitcast, encoded in V. 90 GlobalValue *ExtractTypeInfo(Value *V); 91 92 /// getFCmpCondCode - Return the ISD condition code corresponding to 93 /// the given LLVM IR floating-point condition code. This includes 94 /// consideration of global floating-point math flags. 95 /// 96 ISD::CondCode getFCmpCondCode(FCmpInst::Predicate Pred); 97 98 /// getFCmpCodeWithoutNaN - Given an ISD condition code comparing floats, 99 /// return the equivalent code if we're allowed to assume that NaNs won't occur. 100 ISD::CondCode getFCmpCodeWithoutNaN(ISD::CondCode CC); 101 102 /// getICmpCondCode - Return the ISD condition code corresponding to 103 /// the given LLVM IR integer condition code. 104 ISD::CondCode getICmpCondCode(ICmpInst::Predicate Pred); 105 106 /// getICmpCondCode - Return the LLVM IR integer condition code 107 /// corresponding to the given ISD integer condition code. 108 ICmpInst::Predicate getICmpCondCode(ISD::CondCode Pred); 109 110 /// Test if the given instruction is in a position to be optimized 111 /// with a tail-call. This roughly means that it's in a block with 112 /// a return and there's nothing that needs to be scheduled 113 /// between it and the return. 114 /// 115 /// This function only tests target-independent requirements. 116 bool isInTailCallPosition(const CallBase &Call, const TargetMachine &TM); 117 118 /// Test if given that the input instruction is in the tail call position, if 119 /// there is an attribute mismatch between the caller and the callee that will 120 /// inhibit tail call optimizations. 121 /// \p AllowDifferingSizes is an output parameter which, if forming a tail call 122 /// is permitted, determines whether it's permitted only if the size of the 123 /// caller's and callee's return types match exactly. 124 bool attributesPermitTailCall(const Function *F, const Instruction *I, 125 const ReturnInst *Ret, 126 const TargetLoweringBase &TLI, 127 bool *AllowDifferingSizes = nullptr); 128 129 /// Test if given that the input instruction is in the tail call position if the 130 /// return type or any attributes of the function will inhibit tail call 131 /// optimization. 132 bool returnTypeIsEligibleForTailCall(const Function *F, const Instruction *I, 133 const ReturnInst *Ret, 134 const TargetLoweringBase &TLI); 135 136 DenseMap<const MachineBasicBlock *, int> 137 getEHScopeMembership(const MachineFunction &MF); 138 139 } // End llvm namespace 140 141 #endif 142