1 //===- CodeGen/Analysis.h - CodeGen LLVM IR Analysis Utilities --*- 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 file declares several CodeGen-specific LLVM IR analysis utilities. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #ifndef LLVM_CODEGEN_ANALYSIS_H 15 #define LLVM_CODEGEN_ANALYSIS_H 16 17 #include "llvm/ADT/ArrayRef.h" 18 #include "llvm/ADT/SmallVector.h" 19 #include "llvm/CodeGen/ISDOpcodes.h" 20 #include "llvm/IR/CallSite.h" 21 #include "llvm/IR/InlineAsm.h" 22 #include "llvm/IR/Instructions.h" 23 24 namespace llvm { 25 class GlobalValue; 26 class TargetLoweringBase; 27 class TargetLowering; 28 class TargetMachine; 29 class SDNode; 30 class SDValue; 31 class SelectionDAG; 32 struct EVT; 33 34 /// \brief Compute the linearized index of a member in a nested 35 /// aggregate/struct/array. 36 /// 37 /// Given an LLVM IR aggregate type and a sequence of insertvalue or 38 /// extractvalue indices that identify a member, return the linearized index of 39 /// the start of the member, i.e the number of element in memory before the 40 /// seeked one. This is disconnected from the number of bytes. 41 /// 42 /// \param Ty is the type indexed by \p Indices. 43 /// \param Indices is an optional pointer in the indices list to the current 44 /// index. 45 /// \param IndicesEnd is the end of the indices list. 46 /// \param CurIndex is the current index in the recursion. 47 /// 48 /// \returns \p CurIndex plus the linear index in \p Ty the indices list. 49 unsigned ComputeLinearIndex(Type *Ty, 50 const unsigned *Indices, 51 const unsigned *IndicesEnd, 52 unsigned CurIndex = 0); 53 54 inline unsigned ComputeLinearIndex(Type *Ty, 55 ArrayRef<unsigned> Indices, 56 unsigned CurIndex = 0) { 57 return ComputeLinearIndex(Ty, Indices.begin(), Indices.end(), CurIndex); 58 } 59 60 /// ComputeValueVTs - Given an LLVM IR type, compute a sequence of 61 /// EVTs that represent all the individual underlying 62 /// non-aggregate types that comprise it. 63 /// 64 /// If Offsets is non-null, it points to a vector to be filled in 65 /// with the in-memory offsets of each of the individual values. 66 /// 67 void ComputeValueVTs(const TargetLowering &TLI, Type *Ty, 68 SmallVectorImpl<EVT> &ValueVTs, 69 SmallVectorImpl<uint64_t> *Offsets = nullptr, 70 uint64_t StartingOffset = 0); 71 72 /// ExtractTypeInfo - Returns the type info, possibly bitcast, encoded in V. 73 GlobalValue *ExtractTypeInfo(Value *V); 74 75 /// hasInlineAsmMemConstraint - Return true if the inline asm instruction being 76 /// processed uses a memory 'm' constraint. 77 bool hasInlineAsmMemConstraint(InlineAsm::ConstraintInfoVector &CInfos, 78 const TargetLowering &TLI); 79 80 /// getFCmpCondCode - Return the ISD condition code corresponding to 81 /// the given LLVM IR floating-point condition code. This includes 82 /// consideration of global floating-point math flags. 83 /// 84 ISD::CondCode getFCmpCondCode(FCmpInst::Predicate Pred); 85 86 /// getFCmpCodeWithoutNaN - Given an ISD condition code comparing floats, 87 /// return the equivalent code if we're allowed to assume that NaNs won't occur. 88 ISD::CondCode getFCmpCodeWithoutNaN(ISD::CondCode CC); 89 90 /// getICmpCondCode - Return the ISD condition code corresponding to 91 /// the given LLVM IR integer condition code. 92 /// 93 ISD::CondCode getICmpCondCode(ICmpInst::Predicate Pred); 94 95 /// Test if the given instruction is in a position to be optimized 96 /// with a tail-call. This roughly means that it's in a block with 97 /// a return and there's nothing that needs to be scheduled 98 /// between it and the return. 99 /// 100 /// This function only tests target-independent requirements. 101 bool isInTailCallPosition(ImmutableCallSite CS, const TargetMachine &TM); 102 103 /// Test if given that the input instruction is in the tail call position if the 104 /// return type or any attributes of the function will inhibit tail call 105 /// optimization. 106 bool returnTypeIsEligibleForTailCall(const Function *F, 107 const Instruction *I, 108 const ReturnInst *Ret, 109 const TargetLoweringBase &TLI); 110 111 // True if GV can be left out of the object symbol table. This is the case 112 // for linkonce_odr values whose address is not significant. While legal, it is 113 // not normally profitable to omit them from the .o symbol table. Using this 114 // analysis makes sense when the information can be passed down to the linker 115 // or we are in LTO. 116 bool canBeOmittedFromSymbolTable(const GlobalValue *GV); 117 118 } // End llvm namespace 119 120 #endif 121