LLVM  6.0.0svn
LowLevelTypeImpl.h
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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"
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".
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).
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.
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.
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 
74  explicit LLT(bool isPointer, bool isVector, uint16_t NumElements,
75  unsigned SizeInBits, unsigned AddressSpace) {
76  init(isPointer, isVector, NumElements, SizeInBits, AddressSpace);
77  }
78  explicit LLT() : IsPointer(false), IsVector(false), RawData(0) {}
79 
80  explicit LLT(MVT VT);
81 
82  bool isValid() const { return RawData != 0; }
83 
84  bool isScalar() const { return isValid() && !IsPointer && !IsVector; }
85 
86  bool isPointer() const { return isValid() && IsPointer && !IsVector; }
87 
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.
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.
101  unsigned getSizeInBits() const {
102  if (isPointer() || isScalar())
103  return getScalarSizeInBits();
104  return getScalarSizeInBits() * getNumElements();
105  }
106 
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 
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.
132  LLT getElementType() const {
133  assert(isVector() && "cannot get element type of scalar/aggregate");
134  if (IsPointer)
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);
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
static LLT vector(uint16_t NumElements, LLT ScalarTy)
Get a low-level vector of some number of elements and element type.
Compute iterated dominance frontiers using a linear time algorithm.
Definition: AllocatorList.h:24
unsigned getScalarSizeInBits() const
bool isScalar() const
bool operator!=(const LLT &RHS) const
LLT(bool isPointer, bool isVector, uint16_t NumElements, unsigned SizeInBits, unsigned AddressSpace)
bool isVector() const
LLT getElementType() const
Returns the vector&#39;s element type. Only valid for vector types.
static LLT scalar(unsigned SizeInBits)
Get a low-level scalar or aggregate "bag of bits".
initializer< Ty > init(const Ty &Val)
Definition: CommandLine.h:406
Machine Value Type.
bool isValid() const
unsigned getAddressSpace() const
static bool isEqual(const LLT &LHS, const LLT &RHS)
void print(raw_ostream &OS) const
AddressSpace
Definition: NVPTXBaseInfo.h:22
unsigned getSizeInBits() const
Returns the total size of the type. Must only be called on sized types.
static unsigned getHashValue(const LLT &Ty)
bool isPointer() const
bool operator==(const LLT &RHS) const
raw_ostream & operator<<(raw_ostream &OS, const APInt &I)
Definition: APInt.h:2018
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
static LLT pointer(uint16_t AddressSpace, unsigned SizeInBits)
Get a low-level pointer in the given address space (defaulting to 0).
uint16_t getNumElements() const
Returns the number of elements in a vector LLT.
std::underlying_type< E >::type Mask()
Get a bitmask with 1s in all places up to the high-order bit of E&#39;s largest value.
Definition: BitmaskEnum.h:81
This class implements an extremely fast bulk output stream that can only output to a stream...
Definition: raw_ostream.h:44
static LLT vector(uint16_t NumElements, unsigned ScalarSizeInBits)
Get a low-level vector of some number of elements and element width.