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 class MachineFunction; 31 class ModuleSlotTracker; 32 33 /// MachinePointerInfo - This class contains a discriminated union of 34 /// information about pointers in memory operands, relating them back to LLVM IR 35 /// or to virtual locations (such as frame indices) that are exposed during 36 /// codegen. 37 struct MachinePointerInfo { 38 /// V - This is the IR pointer value for the access, or it is null if unknown. 39 /// If this is null, then the access is to a pointer in the default address 40 /// space. 41 PointerUnion<const Value *, const PseudoSourceValue *> V; 42 43 /// Offset - This is an offset from the base Value*. 44 int64_t Offset; 45 46 explicit MachinePointerInfo(const Value *v = nullptr, int64_t offset = 0) 47 : V(v), Offset(offset) {} 48 49 explicit MachinePointerInfo(const PseudoSourceValue *v, 50 int64_t offset = 0) 51 : V(v), Offset(offset) {} 52 53 MachinePointerInfo getWithOffset(int64_t O) const { 54 if (V.isNull()) return MachinePointerInfo(); 55 if (V.is<const Value*>()) 56 return MachinePointerInfo(V.get<const Value*>(), Offset+O); 57 return MachinePointerInfo(V.get<const PseudoSourceValue*>(), Offset+O); 58 } 59 60 /// getAddrSpace - Return the LLVM IR address space number that this pointer 61 /// points into. 62 unsigned getAddrSpace() const; 63 64 /// getConstantPool - Return a MachinePointerInfo record that refers to the 65 /// constant pool. 66 static MachinePointerInfo getConstantPool(MachineFunction &MF); 67 68 /// getFixedStack - Return a MachinePointerInfo record that refers to the 69 /// the specified FrameIndex. 70 static MachinePointerInfo getFixedStack(MachineFunction &MF, int FI, 71 int64_t Offset = 0); 72 73 /// getJumpTable - Return a MachinePointerInfo record that refers to a 74 /// jump table entry. 75 static MachinePointerInfo getJumpTable(MachineFunction &MF); 76 77 /// getGOT - Return a MachinePointerInfo record that refers to a 78 /// GOT entry. 79 static MachinePointerInfo getGOT(MachineFunction &MF); 80 81 /// getStack - stack pointer relative access. 82 static MachinePointerInfo getStack(MachineFunction &MF, int64_t Offset); 83 }; 84 85 86 //===----------------------------------------------------------------------===// 87 /// MachineMemOperand - A description of a memory reference used in the backend. 88 /// Instead of holding a StoreInst or LoadInst, this class holds the address 89 /// Value of the reference along with a byte size and offset. This allows it 90 /// to describe lowered loads and stores. Also, the special PseudoSourceValue 91 /// objects can be used to represent loads and stores to memory locations 92 /// that aren't explicit in the regular LLVM IR. 93 /// 94 class MachineMemOperand { 95 MachinePointerInfo PtrInfo; 96 uint64_t Size; 97 unsigned Flags; 98 AAMDNodes AAInfo; 99 const MDNode *Ranges; 100 101 public: 102 /// Flags values. These may be or'd together. 103 enum MemOperandFlags { 104 /// The memory access reads data. 105 MOLoad = 1, 106 /// The memory access writes data. 107 MOStore = 2, 108 /// The memory access is volatile. 109 MOVolatile = 4, 110 /// The memory access is non-temporal. 111 MONonTemporal = 8, 112 /// The memory access is invariant. 113 MOInvariant = 16, 114 // Target hints allow target passes to annotate memory operations. 115 MOTargetStartBit = 5, 116 MOTargetNumBits = 3, 117 // This is the number of bits we need to represent flags. 118 MOMaxBits = 8 119 }; 120 121 /// MachineMemOperand - Construct an MachineMemOperand object with the 122 /// specified PtrInfo, flags, size, and base alignment. 123 MachineMemOperand(MachinePointerInfo PtrInfo, unsigned flags, uint64_t s, 124 unsigned base_alignment, 125 const AAMDNodes &AAInfo = AAMDNodes(), 126 const MDNode *Ranges = nullptr); 127 128 const MachinePointerInfo &getPointerInfo() const { return PtrInfo; } 129 130 /// getValue - Return the base address of the memory access. This may either 131 /// be a normal LLVM IR Value, or one of the special values used in CodeGen. 132 /// Special values are those obtained via 133 /// PseudoSourceValue::getFixedStack(int), PseudoSourceValue::getStack, and 134 /// other PseudoSourceValue member functions which return objects which stand 135 /// for frame/stack pointer relative references and other special references 136 /// which are not representable in the high-level IR. 137 const Value *getValue() const { return PtrInfo.V.dyn_cast<const Value*>(); } 138 139 const PseudoSourceValue *getPseudoValue() const { 140 return PtrInfo.V.dyn_cast<const PseudoSourceValue*>(); 141 } 142 143 const void *getOpaqueValue() const { return PtrInfo.V.getOpaqueValue(); } 144 145 /// getFlags - Return the raw flags of the source value, \see MemOperandFlags. 146 unsigned int getFlags() const { return Flags & ((1 << MOMaxBits) - 1); } 147 148 /// Bitwise OR the current flags with the given flags. 149 void setFlags(unsigned f) { Flags |= (f & ((1 << MOMaxBits) - 1)); } 150 151 /// getOffset - For normal values, this is a byte offset added to the base 152 /// address. For PseudoSourceValue::FPRel values, this is the FrameIndex 153 /// number. 154 int64_t getOffset() const { return PtrInfo.Offset; } 155 156 unsigned getAddrSpace() const { return PtrInfo.getAddrSpace(); } 157 158 /// getSize - Return the size in bytes of the memory reference. 159 uint64_t getSize() const { return Size; } 160 161 /// getAlignment - Return the minimum known alignment in bytes of the 162 /// actual memory reference. 163 uint64_t getAlignment() const; 164 165 /// getBaseAlignment - Return the minimum known alignment in bytes of the 166 /// base address, without the offset. 167 uint64_t getBaseAlignment() const { return (1u << (Flags >> MOMaxBits)) >> 1; } 168 169 /// getAAInfo - Return the AA tags for the memory reference. 170 AAMDNodes getAAInfo() const { return AAInfo; } 171 172 /// getRanges - Return the range tag for the memory reference. 173 const MDNode *getRanges() const { return Ranges; } 174 175 bool isLoad() const { return Flags & MOLoad; } 176 bool isStore() const { return Flags & MOStore; } 177 bool isVolatile() const { return Flags & MOVolatile; } 178 bool isNonTemporal() const { return Flags & MONonTemporal; } 179 bool isInvariant() const { return Flags & MOInvariant; } 180 181 /// isUnordered - Returns true if this memory operation doesn't have any 182 /// ordering constraints other than normal aliasing. Volatile and atomic 183 /// memory operations can't be reordered. 184 /// 185 /// Currently, we don't model the difference between volatile and atomic 186 /// operations. They should retain their ordering relative to all memory 187 /// operations. 188 bool isUnordered() const { return !isVolatile(); } 189 190 /// refineAlignment - Update this MachineMemOperand to reflect the alignment 191 /// of MMO, if it has a greater alignment. This must only be used when the 192 /// new alignment applies to all users of this MachineMemOperand. 193 void refineAlignment(const MachineMemOperand *MMO); 194 195 /// setValue - Change the SourceValue for this MachineMemOperand. This 196 /// should only be used when an object is being relocated and all references 197 /// to it are being updated. 198 void setValue(const Value *NewSV) { PtrInfo.V = NewSV; } 199 void setValue(const PseudoSourceValue *NewSV) { PtrInfo.V = NewSV; } 200 void setOffset(int64_t NewOffset) { PtrInfo.Offset = NewOffset; } 201 202 /// Profile - Gather unique data for the object. 203 /// 204 void Profile(FoldingSetNodeID &ID) const; 205 206 /// Support for operator<<. 207 /// @{ 208 void print(raw_ostream &OS) const; 209 void print(raw_ostream &OS, ModuleSlotTracker &MST) const; 210 /// @} 211 212 friend bool operator==(const MachineMemOperand &LHS, 213 const MachineMemOperand &RHS) { 214 return LHS.getValue() == RHS.getValue() && 215 LHS.getPseudoValue() == RHS.getPseudoValue() && 216 LHS.getSize() == RHS.getSize() && 217 LHS.getOffset() == RHS.getOffset() && 218 LHS.getFlags() == RHS.getFlags() && 219 LHS.getAAInfo() == RHS.getAAInfo() && 220 LHS.getRanges() == RHS.getRanges() && 221 LHS.getAlignment() == RHS.getAlignment() && 222 LHS.getAddrSpace() == RHS.getAddrSpace(); 223 } 224 225 friend bool operator!=(const MachineMemOperand &LHS, 226 const MachineMemOperand &RHS) { 227 return !(LHS == RHS); 228 } 229 }; 230 231 inline raw_ostream &operator<<(raw_ostream &OS, const MachineMemOperand &MRO) { 232 MRO.print(OS); 233 return OS; 234 } 235 236 } // End llvm namespace 237 238 #endif 239
