1 //==- llvm/CodeGen/MachineMemOperand.h - MachineMemOperand class -*- 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 contains the declaration of the MachineMemOperand class, which is a 11 // description of a memory reference. It is used to help track dependencies 12 // in the backend. 13 // 14 //===----------------------------------------------------------------------===// 15 16 #ifndef LLVM_CODEGEN_MACHINEMEMOPERAND_H 17 #define LLVM_CODEGEN_MACHINEMEMOPERAND_H 18 19 #include "llvm/ADT/PointerUnion.h" 20 #include "llvm/CodeGen/PseudoSourceValue.h" 21 #include "llvm/IR/Metadata.h" 22 #include "llvm/IR/Value.h" // PointerLikeTypeTraits<Value*> 23 #include "llvm/Support/DataTypes.h" 24 25 namespace llvm { 26 27 class FoldingSetNodeID; 28 class MDNode; 29 class raw_ostream; 30 31 /// MachinePointerInfo - This class contains a discriminated union of 32 /// information about pointers in memory operands, relating them back to LLVM IR 33 /// or to virtual locations (such as frame indices) that are exposed during 34 /// codegen. 35 struct MachinePointerInfo { 36 /// V - This is the IR pointer value for the access, or it is null if unknown. 37 /// If this is null, then the access is to a pointer in the default address 38 /// space. 39 PointerUnion<const Value *, const PseudoSourceValue *> V; 40 41 /// Offset - This is an offset from the base Value*. 42 int64_t Offset; 43 44 explicit MachinePointerInfo(const Value *v = nullptr, int64_t offset = 0) 45 : V(v), Offset(offset) {} 46 47 explicit MachinePointerInfo(const PseudoSourceValue *v, 48 int64_t offset = 0) 49 : V(v), Offset(offset) {} 50 51 MachinePointerInfo getWithOffset(int64_t O) const { 52 if (V.isNull()) return MachinePointerInfo(); 53 if (V.is<const Value*>()) 54 return MachinePointerInfo(V.get<const Value*>(), Offset+O); 55 return MachinePointerInfo(V.get<const PseudoSourceValue*>(), Offset+O); 56 } 57 58 /// getAddrSpace - Return the LLVM IR address space number that this pointer 59 /// points into. 60 unsigned getAddrSpace() const; 61 62 /// getConstantPool - Return a MachinePointerInfo record that refers to the 63 /// constant pool. 64 static MachinePointerInfo getConstantPool(); 65 66 /// getFixedStack - Return a MachinePointerInfo record that refers to the 67 /// the specified FrameIndex. 68 static MachinePointerInfo getFixedStack(int FI, int64_t offset = 0); 69 70 /// getJumpTable - Return a MachinePointerInfo record that refers to a 71 /// jump table entry. 72 static MachinePointerInfo getJumpTable(); 73 74 /// getGOT - Return a MachinePointerInfo record that refers to a 75 /// GOT entry. 76 static MachinePointerInfo getGOT(); 77 78 /// getStack - stack pointer relative access. 79 static MachinePointerInfo getStack(int64_t Offset); 80 }; 81 82 83 //===----------------------------------------------------------------------===// 84 /// MachineMemOperand - A description of a memory reference used in the backend. 85 /// Instead of holding a StoreInst or LoadInst, this class holds the address 86 /// Value of the reference along with a byte size and offset. This allows it 87 /// to describe lowered loads and stores. Also, the special PseudoSourceValue 88 /// objects can be used to represent loads and stores to memory locations 89 /// that aren't explicit in the regular LLVM IR. 90 /// 91 class MachineMemOperand { 92 MachinePointerInfo PtrInfo; 93 uint64_t Size; 94 unsigned Flags; 95 AAMDNodes AAInfo; 96 const MDNode *Ranges; 97 98 public: 99 /// Flags values. These may be or'd together. 100 enum MemOperandFlags { 101 /// The memory access reads data. 102 MOLoad = 1, 103 /// The memory access writes data. 104 MOStore = 2, 105 /// The memory access is volatile. 106 MOVolatile = 4, 107 /// The memory access is non-temporal. 108 MONonTemporal = 8, 109 /// The memory access is invariant. 110 MOInvariant = 16, 111 // Target hints allow target passes to annotate memory operations. 112 MOTargetStartBit = 5, 113 MOTargetNumBits = 3, 114 // This is the number of bits we need to represent flags. 115 MOMaxBits = 8 116 }; 117 118 /// MachineMemOperand - Construct an MachineMemOperand object with the 119 /// specified PtrInfo, flags, size, and base alignment. 120 MachineMemOperand(MachinePointerInfo PtrInfo, unsigned flags, uint64_t s, 121 unsigned base_alignment, 122 const AAMDNodes &AAInfo = AAMDNodes(), 123 const MDNode *Ranges = nullptr); 124 125 const MachinePointerInfo &getPointerInfo() const { return PtrInfo; } 126 127 /// getValue - Return the base address of the memory access. This may either 128 /// be a normal LLVM IR Value, or one of the special values used in CodeGen. 129 /// Special values are those obtained via 130 /// PseudoSourceValue::getFixedStack(int), PseudoSourceValue::getStack, and 131 /// other PseudoSourceValue member functions which return objects which stand 132 /// for frame/stack pointer relative references and other special references 133 /// which are not representable in the high-level IR. 134 const Value *getValue() const { return PtrInfo.V.dyn_cast<const Value*>(); } 135 136 const PseudoSourceValue *getPseudoValue() const { 137 return PtrInfo.V.dyn_cast<const PseudoSourceValue*>(); 138 } 139 140 const void *getOpaqueValue() const { return PtrInfo.V.getOpaqueValue(); } 141 142 /// getFlags - Return the raw flags of the source value, \see MemOperandFlags. 143 unsigned int getFlags() const { return Flags & ((1 << MOMaxBits) - 1); } 144 145 /// Bitwise OR the current flags with the given flags. 146 void setFlags(unsigned f) { Flags |= (f & ((1 << MOMaxBits) - 1)); } 147 148 /// getOffset - For normal values, this is a byte offset added to the base 149 /// address. For PseudoSourceValue::FPRel values, this is the FrameIndex 150 /// number. 151 int64_t getOffset() const { return PtrInfo.Offset; } 152 153 unsigned getAddrSpace() const { return PtrInfo.getAddrSpace(); } 154 155 /// getSize - Return the size in bytes of the memory reference. 156 uint64_t getSize() const { return Size; } 157 158 /// getAlignment - Return the minimum known alignment in bytes of the 159 /// actual memory reference. 160 uint64_t getAlignment() const; 161 162 /// getBaseAlignment - Return the minimum known alignment in bytes of the 163 /// base address, without the offset. 164 uint64_t getBaseAlignment() const { return (1u << (Flags >> MOMaxBits)) >> 1; } 165 166 /// getAAInfo - Return the AA tags for the memory reference. 167 AAMDNodes getAAInfo() const { return AAInfo; } 168 169 /// getRanges - Return the range tag for the memory reference. 170 const MDNode *getRanges() const { return Ranges; } 171 172 bool isLoad() const { return Flags & MOLoad; } 173 bool isStore() const { return Flags & MOStore; } 174 bool isVolatile() const { return Flags & MOVolatile; } 175 bool isNonTemporal() const { return Flags & MONonTemporal; } 176 bool isInvariant() const { return Flags & MOInvariant; } 177 178 /// isUnordered - Returns true if this memory operation doesn't have any 179 /// ordering constraints other than normal aliasing. Volatile and atomic 180 /// memory operations can't be reordered. 181 /// 182 /// Currently, we don't model the difference between volatile and atomic 183 /// operations. They should retain their ordering relative to all memory 184 /// operations. 185 bool isUnordered() const { return !isVolatile(); } 186 187 /// refineAlignment - Update this MachineMemOperand to reflect the alignment 188 /// of MMO, if it has a greater alignment. This must only be used when the 189 /// new alignment applies to all users of this MachineMemOperand. 190 void refineAlignment(const MachineMemOperand *MMO); 191 192 /// setValue - Change the SourceValue for this MachineMemOperand. This 193 /// should only be used when an object is being relocated and all references 194 /// to it are being updated. 195 void setValue(const Value *NewSV) { PtrInfo.V = NewSV; } 196 void setValue(const PseudoSourceValue *NewSV) { PtrInfo.V = NewSV; } 197 void setOffset(int64_t NewOffset) { PtrInfo.Offset = NewOffset; } 198 199 /// Profile - Gather unique data for the object. 200 /// 201 void Profile(FoldingSetNodeID &ID) const; 202 203 friend bool operator==(const MachineMemOperand &LHS, 204 const MachineMemOperand &RHS) { 205 return LHS.getValue() == RHS.getValue() && 206 LHS.getPseudoValue() == RHS.getPseudoValue() && 207 LHS.getSize() == RHS.getSize() && 208 LHS.getOffset() == RHS.getOffset() && 209 LHS.getFlags() == RHS.getFlags() && 210 LHS.getAAInfo() == RHS.getAAInfo() && 211 LHS.getRanges() == RHS.getRanges() && 212 LHS.getAlignment() == RHS.getAlignment() && 213 LHS.getAddrSpace() == RHS.getAddrSpace(); 214 } 215 216 friend bool operator!=(const MachineMemOperand &LHS, 217 const MachineMemOperand &RHS) { 218 return !(LHS == RHS); 219 } 220 }; 221 222 raw_ostream &operator<<(raw_ostream &OS, const MachineMemOperand &MRO); 223 224 } // End llvm namespace 225 226 #endif 227
