1 //== llvm/Support/LowLevelTypeImpl.h --------------------------- -*- 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 /// Implement a low-level type suitable for MachineInstr level instruction 11 /// selection. 12 /// 13 /// For a type attached to a MachineInstr, we only care about 2 details: total 14 /// size and the number of vector lanes (if any). Accordingly, there are 4 15 /// possible valid type-kinds: 16 /// 17 /// * `sN` for scalars and aggregates 18 /// * `<N x sM>` for vectors, which must have at least 2 elements. 19 /// * `pN` for pointers 20 /// 21 /// Other information required for correct selection is expected to be carried 22 /// by the opcode, or non-type flags. For example the distinction between G_ADD 23 /// and G_FADD for int/float or fast-math flags. 24 // 25 //===----------------------------------------------------------------------===// 26 27 #ifndef LLVM_SUPPORT_LOWLEVELTYPEIMPL_H 28 #define LLVM_SUPPORT_LOWLEVELTYPEIMPL_H 29 30 #include "llvm/ADT/DenseMapInfo.h" 31 #include "llvm/Support/MachineValueType.h" 32 #include <cassert> 33 34 namespace llvm { 35 36 class DataLayout; 37 class Type; 38 class raw_ostream; 39 40 class LLT { 41 public: 42 /// Get a low-level scalar or aggregate "bag of bits". scalar(unsigned SizeInBits)43 static LLT scalar(unsigned SizeInBits) { 44 assert(SizeInBits > 0 && "invalid scalar size"); 45 return LLT{/*isPointer=*/false, /*isVector=*/false, /*NumElements=*/0, 46 SizeInBits, /*AddressSpace=*/0}; 47 } 48 49 /// Get a low-level pointer in the given address space (defaulting to 0). pointer(uint16_t AddressSpace,unsigned SizeInBits)50 static LLT pointer(uint16_t AddressSpace, unsigned SizeInBits) { 51 assert(SizeInBits > 0 && "invalid pointer size"); 52 return LLT{/*isPointer=*/true, /*isVector=*/false, /*NumElements=*/0, 53 SizeInBits, AddressSpace}; 54 } 55 56 /// Get a low-level vector of some number of elements and element width. 57 /// \p NumElements must be at least 2. vector(uint16_t NumElements,unsigned ScalarSizeInBits)58 static LLT vector(uint16_t NumElements, unsigned ScalarSizeInBits) { 59 assert(NumElements > 1 && "invalid number of vector elements"); 60 assert(ScalarSizeInBits > 0 && "invalid vector element size"); 61 return LLT{/*isPointer=*/false, /*isVector=*/true, NumElements, 62 ScalarSizeInBits, /*AddressSpace=*/0}; 63 } 64 65 /// Get a low-level vector of some number of elements and element type. vector(uint16_t NumElements,LLT ScalarTy)66 static LLT vector(uint16_t NumElements, LLT ScalarTy) { 67 assert(NumElements > 1 && "invalid number of vector elements"); 68 assert(!ScalarTy.isVector() && "invalid vector element type"); 69 return LLT{ScalarTy.isPointer(), /*isVector=*/true, NumElements, 70 ScalarTy.getSizeInBits(), 71 ScalarTy.isPointer() ? ScalarTy.getAddressSpace() : 0}; 72 } 73 LLT(bool isPointer,bool isVector,uint16_t NumElements,unsigned SizeInBits,unsigned AddressSpace)74 explicit LLT(bool isPointer, bool isVector, uint16_t NumElements, 75 unsigned SizeInBits, unsigned AddressSpace) { 76 init(isPointer, isVector, NumElements, SizeInBits, AddressSpace); 77 } LLT()78 explicit LLT() : IsPointer(false), IsVector(false), RawData(0) {} 79 80 explicit LLT(MVT VT); 81 isValid()82 bool isValid() const { return RawData != 0; } 83 isScalar()84 bool isScalar() const { return isValid() && !IsPointer && !IsVector; } 85 isPointer()86 bool isPointer() const { return isValid() && IsPointer && !IsVector; } 87 isVector()88 bool isVector() const { return isValid() && IsVector; } 89 90 /// Returns the number of elements in a vector LLT. Must only be called on 91 /// vector types. getNumElements()92 uint16_t getNumElements() const { 93 assert(IsVector && "cannot get number of elements on scalar/aggregate"); 94 if (!IsPointer) 95 return getFieldValue(VectorElementsFieldInfo); 96 else 97 return getFieldValue(PointerVectorElementsFieldInfo); 98 } 99 100 /// Returns the total size of the type. Must only be called on sized types. getSizeInBits()101 unsigned getSizeInBits() const { 102 if (isPointer() || isScalar()) 103 return getScalarSizeInBits(); 104 return getScalarSizeInBits() * getNumElements(); 105 } 106 getScalarSizeInBits()107 unsigned getScalarSizeInBits() const { 108 assert(RawData != 0 && "Invalid Type"); 109 if (!IsVector) { 110 if (!IsPointer) 111 return getFieldValue(ScalarSizeFieldInfo); 112 else 113 return getFieldValue(PointerSizeFieldInfo); 114 } else { 115 if (!IsPointer) 116 return getFieldValue(VectorSizeFieldInfo); 117 else 118 return getFieldValue(PointerVectorSizeFieldInfo); 119 } 120 } 121 getAddressSpace()122 unsigned getAddressSpace() const { 123 assert(RawData != 0 && "Invalid Type"); 124 assert(IsPointer && "cannot get address space of non-pointer type"); 125 if (!IsVector) 126 return getFieldValue(PointerAddressSpaceFieldInfo); 127 else 128 return getFieldValue(PointerVectorAddressSpaceFieldInfo); 129 } 130 131 /// Returns the vector's element type. Only valid for vector types. getElementType()132 LLT getElementType() const { 133 assert(isVector() && "cannot get element type of scalar/aggregate"); 134 if (IsPointer) 135 return pointer(getAddressSpace(), getScalarSizeInBits()); 136 else 137 return scalar(getScalarSizeInBits()); 138 } 139 140 void print(raw_ostream &OS) const; 141 142 bool operator==(const LLT &RHS) const { 143 return IsPointer == RHS.IsPointer && IsVector == RHS.IsVector && 144 RHS.RawData == RawData; 145 } 146 147 bool operator!=(const LLT &RHS) const { return !(*this == RHS); } 148 149 friend struct DenseMapInfo<LLT>; 150 151 private: 152 /// LLT is packed into 64 bits as follows: 153 /// isPointer : 1 154 /// isVector : 1 155 /// with 62 bits remaining for Kind-specific data, packed in bitfields 156 /// as described below. As there isn't a simple portable way to pack bits 157 /// into bitfields, here the different fields in the packed structure is 158 /// described in static const *Field variables. Each of these variables 159 /// is a 2-element array, with the first element describing the bitfield size 160 /// and the second element describing the bitfield offset. 161 typedef int BitFieldInfo[2]; 162 /// 163 /// This is how the bitfields are packed per Kind: 164 /// * Invalid: 165 /// gets encoded as RawData == 0, as that is an invalid encoding, since for 166 /// valid encodings, SizeInBits/SizeOfElement must be larger than 0. 167 /// * Non-pointer scalar (isPointer == 0 && isVector == 0): 168 /// SizeInBits: 32; 169 static const constexpr BitFieldInfo ScalarSizeFieldInfo{32, 0}; 170 /// * Pointer (isPointer == 1 && isVector == 0): 171 /// SizeInBits: 16; 172 /// AddressSpace: 23; 173 static const constexpr BitFieldInfo PointerSizeFieldInfo{16, 0}; 174 static const constexpr BitFieldInfo PointerAddressSpaceFieldInfo{ 175 23, PointerSizeFieldInfo[0] + PointerSizeFieldInfo[1]}; 176 /// * Vector-of-non-pointer (isPointer == 0 && isVector == 1): 177 /// NumElements: 16; 178 /// SizeOfElement: 32; 179 static const constexpr BitFieldInfo VectorElementsFieldInfo{16, 0}; 180 static const constexpr BitFieldInfo VectorSizeFieldInfo{ 181 32, VectorElementsFieldInfo[0] + VectorElementsFieldInfo[1]}; 182 /// * Vector-of-pointer (isPointer == 1 && isVector == 1): 183 /// NumElements: 16; 184 /// SizeOfElement: 16; 185 /// AddressSpace: 23; 186 static const constexpr BitFieldInfo PointerVectorElementsFieldInfo{16, 0}; 187 static const constexpr BitFieldInfo PointerVectorSizeFieldInfo{ 188 16, 189 PointerVectorElementsFieldInfo[1] + PointerVectorElementsFieldInfo[0]}; 190 static const constexpr BitFieldInfo PointerVectorAddressSpaceFieldInfo{ 191 23, PointerVectorSizeFieldInfo[1] + PointerVectorSizeFieldInfo[0]}; 192 193 uint64_t IsPointer : 1; 194 uint64_t IsVector : 1; 195 uint64_t RawData : 62; 196 197 static uint64_t getMask(const BitFieldInfo FieldInfo) { 198 const int FieldSizeInBits = FieldInfo[0]; 199 return (((uint64_t)1) << FieldSizeInBits) - 1; 200 } 201 static uint64_t maskAndShift(uint64_t Val, uint64_t Mask, uint8_t Shift) { 202 assert(Val <= Mask && "Value too large for field"); 203 return (Val & Mask) << Shift; 204 } 205 static uint64_t maskAndShift(uint64_t Val, const BitFieldInfo FieldInfo) { 206 return maskAndShift(Val, getMask(FieldInfo), FieldInfo[1]); 207 } 208 uint64_t getFieldValue(const BitFieldInfo FieldInfo) const { 209 return getMask(FieldInfo) & (RawData >> FieldInfo[1]); 210 } 211 212 void init(bool IsPointer, bool IsVector, uint16_t NumElements, 213 unsigned SizeInBits, unsigned AddressSpace) { 214 this->IsPointer = IsPointer; 215 this->IsVector = IsVector; 216 if (!IsVector) { 217 if (!IsPointer) 218 RawData = maskAndShift(SizeInBits, ScalarSizeFieldInfo); 219 else 220 RawData = maskAndShift(SizeInBits, PointerSizeFieldInfo) | 221 maskAndShift(AddressSpace, PointerAddressSpaceFieldInfo); 222 } else { 223 assert(NumElements > 1 && "invalid number of vector elements"); 224 if (!IsPointer) 225 RawData = maskAndShift(NumElements, VectorElementsFieldInfo) | 226 maskAndShift(SizeInBits, VectorSizeFieldInfo); 227 else 228 RawData = 229 maskAndShift(NumElements, PointerVectorElementsFieldInfo) | 230 maskAndShift(SizeInBits, PointerVectorSizeFieldInfo) | 231 maskAndShift(AddressSpace, PointerVectorAddressSpaceFieldInfo); 232 } 233 } 234 }; 235 236 inline raw_ostream& operator<<(raw_ostream &OS, const LLT &Ty) { 237 Ty.print(OS); 238 return OS; 239 } 240 241 template<> struct DenseMapInfo<LLT> { 242 static inline LLT getEmptyKey() { 243 LLT Invalid; 244 Invalid.IsPointer = true; 245 return Invalid; 246 } 247 static inline LLT getTombstoneKey() { 248 LLT Invalid; 249 Invalid.IsVector = true; 250 return Invalid; 251 } 252 static inline unsigned getHashValue(const LLT &Ty) { 253 uint64_t Val = ((uint64_t)Ty.RawData) << 2 | ((uint64_t)Ty.IsPointer) << 1 | 254 ((uint64_t)Ty.IsVector); 255 return DenseMapInfo<uint64_t>::getHashValue(Val); 256 } 257 static bool isEqual(const LLT &LHS, const LLT &RHS) { 258 return LHS == RHS; 259 } 260 }; 261 262 } 263 264 #endif // LLVM_SUPPORT_LOWLEVELTYPEIMPL_H 265