llvm.org GIT mirror llvm / release_35@215010 include / llvm / IR / Operator.h
release_35@215010

Tree @release_35@215010 (Download .tar.gz)

Operator.h @release_35@215010raw · history · blame

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
//===-- llvm/Operator.h - Operator utility subclass -------------*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines various classes for working with Instructions and
// ConstantExprs.
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_IR_OPERATOR_H
#define LLVM_IR_OPERATOR_H

#include "llvm/IR/Constants.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/GetElementPtrTypeIterator.h"
#include "llvm/IR/Instruction.h"
#include "llvm/IR/Type.h"

namespace llvm {

class GetElementPtrInst;
class BinaryOperator;
class ConstantExpr;

/// Operator - This is a utility class that provides an abstraction for the
/// common functionality between Instructions and ConstantExprs.
///
class Operator : public User {
private:
  // The Operator class is intended to be used as a utility, and is never itself
  // instantiated.
  void *operator new(size_t, unsigned) LLVM_DELETED_FUNCTION;
  void *operator new(size_t s) LLVM_DELETED_FUNCTION;
  Operator() LLVM_DELETED_FUNCTION;

protected:
  // NOTE: Cannot use LLVM_DELETED_FUNCTION because it's not legal to delete
  // an overridden method that's not deleted in the base class. Cannot leave
  // this unimplemented because that leads to an ODR-violation.
  ~Operator();

public:
  /// getOpcode - Return the opcode for this Instruction or ConstantExpr.
  ///
  unsigned getOpcode() const {
    if (const Instruction *I = dyn_cast<Instruction>(this))
      return I->getOpcode();
    return cast<ConstantExpr>(this)->getOpcode();
  }

  /// getOpcode - If V is an Instruction or ConstantExpr, return its
  /// opcode. Otherwise return UserOp1.
  ///
  static unsigned getOpcode(const Value *V) {
    if (const Instruction *I = dyn_cast<Instruction>(V))
      return I->getOpcode();
    if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(V))
      return CE->getOpcode();
    return Instruction::UserOp1;
  }

  static inline bool classof(const Instruction *) { return true; }
  static inline bool classof(const ConstantExpr *) { return true; }
  static inline bool classof(const Value *V) {
    return isa<Instruction>(V) || isa<ConstantExpr>(V);
  }
};

/// OverflowingBinaryOperator - Utility class for integer arithmetic operators
/// which may exhibit overflow - Add, Sub, and Mul. It does not include SDiv,
/// despite that operator having the potential for overflow.
///
class OverflowingBinaryOperator : public Operator {
public:
  enum {
    NoUnsignedWrap = (1 << 0),
    NoSignedWrap   = (1 << 1)
  };

private:
  friend class BinaryOperator;
  friend class ConstantExpr;
  void setHasNoUnsignedWrap(bool B) {
    SubclassOptionalData =
      (SubclassOptionalData & ~NoUnsignedWrap) | (B * NoUnsignedWrap);
  }
  void setHasNoSignedWrap(bool B) {
    SubclassOptionalData =
      (SubclassOptionalData & ~NoSignedWrap) | (B * NoSignedWrap);
  }

public:
  /// hasNoUnsignedWrap - Test whether this operation is known to never
  /// undergo unsigned overflow, aka the nuw property.
  bool hasNoUnsignedWrap() const {
    return SubclassOptionalData & NoUnsignedWrap;
  }

  /// hasNoSignedWrap - Test whether this operation is known to never
  /// undergo signed overflow, aka the nsw property.
  bool hasNoSignedWrap() const {
    return (SubclassOptionalData & NoSignedWrap) != 0;
  }

  static inline bool classof(const Instruction *I) {
    return I->getOpcode() == Instruction::Add ||
           I->getOpcode() == Instruction::Sub ||
           I->getOpcode() == Instruction::Mul ||
           I->getOpcode() == Instruction::Shl;
  }
  static inline bool classof(const ConstantExpr *CE) {
    return CE->getOpcode() == Instruction::Add ||
           CE->getOpcode() == Instruction::Sub ||
           CE->getOpcode() == Instruction::Mul ||
           CE->getOpcode() == Instruction::Shl;
  }
  static inline bool classof(const Value *V) {
    return (isa<Instruction>(V) && classof(cast<Instruction>(V))) ||
           (isa<ConstantExpr>(V) && classof(cast<ConstantExpr>(V)));
  }
};

/// PossiblyExactOperator - A udiv or sdiv instruction, which can be marked as
/// "exact", indicating that no bits are destroyed.
class PossiblyExactOperator : public Operator {
public:
  enum {
    IsExact = (1 << 0)
  };

private:
  friend class BinaryOperator;
  friend class ConstantExpr;
  void setIsExact(bool B) {
    SubclassOptionalData = (SubclassOptionalData & ~IsExact) | (B * IsExact);
  }

public:
  /// isExact - Test whether this division is known to be exact, with
  /// zero remainder.
  bool isExact() const {
    return SubclassOptionalData & IsExact;
  }

  static bool isPossiblyExactOpcode(unsigned OpC) {
    return OpC == Instruction::SDiv ||
           OpC == Instruction::UDiv ||
           OpC == Instruction::AShr ||
           OpC == Instruction::LShr;
  }
  static inline bool classof(const ConstantExpr *CE) {
    return isPossiblyExactOpcode(CE->getOpcode());
  }
  static inline bool classof(const Instruction *I) {
    return isPossiblyExactOpcode(I->getOpcode());
  }
  static inline bool classof(const Value *V) {
    return (isa<Instruction>(V) && classof(cast<Instruction>(V))) ||
           (isa<ConstantExpr>(V) && classof(cast<ConstantExpr>(V)));
  }
};

/// Convenience struct for specifying and reasoning about fast-math flags.
class FastMathFlags {
private:
  friend class FPMathOperator;
  unsigned Flags;
  FastMathFlags(unsigned F) : Flags(F) { }

public:
  enum {
    UnsafeAlgebra   = (1 << 0),
    NoNaNs          = (1 << 1),
    NoInfs          = (1 << 2),
    NoSignedZeros   = (1 << 3),
    AllowReciprocal = (1 << 4)
  };

  FastMathFlags() : Flags(0)
  { }

  /// Whether any flag is set
  bool any() { return Flags != 0; }

  /// Set all the flags to false
  void clear() { Flags = 0; }

  /// Flag queries
  bool noNaNs()          { return 0 != (Flags & NoNaNs); }
  bool noInfs()          { return 0 != (Flags & NoInfs); }
  bool noSignedZeros()   { return 0 != (Flags & NoSignedZeros); }
  bool allowReciprocal() { return 0 != (Flags & AllowReciprocal); }
  bool unsafeAlgebra()   { return 0 != (Flags & UnsafeAlgebra); }

  /// Flag setters
  void setNoNaNs()          { Flags |= NoNaNs; }
  void setNoInfs()          { Flags |= NoInfs; }
  void setNoSignedZeros()   { Flags |= NoSignedZeros; }
  void setAllowReciprocal() { Flags |= AllowReciprocal; }
  void setUnsafeAlgebra() {
    Flags |= UnsafeAlgebra;
    setNoNaNs();
    setNoInfs();
    setNoSignedZeros();
    setAllowReciprocal();
  }

  void operator&=(const FastMathFlags &OtherFlags) {
    Flags &= OtherFlags.Flags;
  }
};


/// FPMathOperator - Utility class for floating point operations which can have
/// information about relaxed accuracy requirements attached to them.
class FPMathOperator : public Operator {
private:
  friend class Instruction;

  void setHasUnsafeAlgebra(bool B) {
    SubclassOptionalData =
      (SubclassOptionalData & ~FastMathFlags::UnsafeAlgebra) |
      (B * FastMathFlags::UnsafeAlgebra);

    // Unsafe algebra implies all the others
    if (B) {
      setHasNoNaNs(true);
      setHasNoInfs(true);
      setHasNoSignedZeros(true);
      setHasAllowReciprocal(true);
    }
  }
  void setHasNoNaNs(bool B) {
    SubclassOptionalData =
      (SubclassOptionalData & ~FastMathFlags::NoNaNs) |
      (B * FastMathFlags::NoNaNs);
  }
  void setHasNoInfs(bool B) {
    SubclassOptionalData =
      (SubclassOptionalData & ~FastMathFlags::NoInfs) |
      (B * FastMathFlags::NoInfs);
  }
  void setHasNoSignedZeros(bool B) {
    SubclassOptionalData =
      (SubclassOptionalData & ~FastMathFlags::NoSignedZeros) |
      (B * FastMathFlags::NoSignedZeros);
  }
  void setHasAllowReciprocal(bool B) {
    SubclassOptionalData =
      (SubclassOptionalData & ~FastMathFlags::AllowReciprocal) |
      (B * FastMathFlags::AllowReciprocal);
  }

  /// Convenience function for setting all the fast-math flags
  void setFastMathFlags(FastMathFlags FMF) {
    SubclassOptionalData |= FMF.Flags;
  }

public:
  /// Test whether this operation is permitted to be
  /// algebraically transformed, aka the 'A' fast-math property.
  bool hasUnsafeAlgebra() const {
    return (SubclassOptionalData & FastMathFlags::UnsafeAlgebra) != 0;
  }

  /// Test whether this operation's arguments and results are to be
  /// treated as non-NaN, aka the 'N' fast-math property.
  bool hasNoNaNs() const {
    return (SubclassOptionalData & FastMathFlags::NoNaNs) != 0;
  }

  /// Test whether this operation's arguments and results are to be
  /// treated as NoN-Inf, aka the 'I' fast-math property.
  bool hasNoInfs() const {
    return (SubclassOptionalData & FastMathFlags::NoInfs) != 0;
  }

  /// Test whether this operation can treat the sign of zero
  /// as insignificant, aka the 'S' fast-math property.
  bool hasNoSignedZeros() const {
    return (SubclassOptionalData & FastMathFlags::NoSignedZeros) != 0;
  }

  /// Test whether this operation is permitted to use
  /// reciprocal instead of division, aka the 'R' fast-math property.
  bool hasAllowReciprocal() const {
    return (SubclassOptionalData & FastMathFlags::AllowReciprocal) != 0;
  }

  /// Convenience function for getting all the fast-math flags
  FastMathFlags getFastMathFlags() const {
    return FastMathFlags(SubclassOptionalData);
  }

  /// \brief Get the maximum error permitted by this operation in ULPs.  An
  /// accuracy of 0.0 means that the operation should be performed with the
  /// default precision.
  float getFPAccuracy() const;

  static inline bool classof(const Instruction *I) {
    return I->getType()->isFPOrFPVectorTy();
  }
  static inline bool classof(const Value *V) {
    return isa<Instruction>(V) && classof(cast<Instruction>(V));
  }
};


/// ConcreteOperator - A helper template for defining operators for individual
/// opcodes.
template<typename SuperClass, unsigned Opc>
class ConcreteOperator : public SuperClass {
public:
  static inline bool classof(const Instruction *I) {
    return I->getOpcode() == Opc;
  }
  static inline bool classof(const ConstantExpr *CE) {
    return CE->getOpcode() == Opc;
  }
  static inline bool classof(const Value *V) {
    return (isa<Instruction>(V) && classof(cast<Instruction>(V))) ||
           (isa<ConstantExpr>(V) && classof(cast<ConstantExpr>(V)));
  }
};

class AddOperator
  : public ConcreteOperator<OverflowingBinaryOperator, Instruction::Add> {
};
class SubOperator
  : public ConcreteOperator<OverflowingBinaryOperator, Instruction::Sub> {
};
class MulOperator
  : public ConcreteOperator<OverflowingBinaryOperator, Instruction::Mul> {
};
class ShlOperator
  : public ConcreteOperator<OverflowingBinaryOperator, Instruction::Shl> {
};


class SDivOperator
  : public ConcreteOperator<PossiblyExactOperator, Instruction::SDiv> {
};
class UDivOperator
  : public ConcreteOperator<PossiblyExactOperator, Instruction::UDiv> {
};
class AShrOperator
  : public ConcreteOperator<PossiblyExactOperator, Instruction::AShr> {
};
class LShrOperator
  : public ConcreteOperator<PossiblyExactOperator, Instruction::LShr> {
};



class GEPOperator
  : public ConcreteOperator<Operator, Instruction::GetElementPtr> {
  enum {
    IsInBounds = (1 << 0)
  };

  friend class GetElementPtrInst;
  friend class ConstantExpr;
  void setIsInBounds(bool B) {
    SubclassOptionalData =
      (SubclassOptionalData & ~IsInBounds) | (B * IsInBounds);
  }

public:
  /// isInBounds - Test whether this is an inbounds GEP, as defined
  /// by LangRef.html.
  bool isInBounds() const {
    return SubclassOptionalData & IsInBounds;
  }

  inline op_iterator       idx_begin()       { return op_begin()+1; }
  inline const_op_iterator idx_begin() const { return op_begin()+1; }
  inline op_iterator       idx_end()         { return op_end(); }
  inline const_op_iterator idx_end()   const { return op_end(); }

  Value *getPointerOperand() {
    return getOperand(0);
  }
  const Value *getPointerOperand() const {
    return getOperand(0);
  }
  static unsigned getPointerOperandIndex() {
    return 0U;                      // get index for modifying correct operand
  }

  /// getPointerOperandType - Method to return the pointer operand as a
  /// PointerType.
  Type *getPointerOperandType() const {
    return getPointerOperand()->getType();
  }

  /// getPointerAddressSpace - Method to return the address space of the
  /// pointer operand.
  unsigned getPointerAddressSpace() const {
    return cast<PointerType>(getPointerOperandType())->getAddressSpace();
  }

  unsigned getNumIndices() const {  // Note: always non-negative
    return getNumOperands() - 1;
  }

  bool hasIndices() const {
    return getNumOperands() > 1;
  }

  /// hasAllZeroIndices - Return true if all of the indices of this GEP are
  /// zeros.  If so, the result pointer and the first operand have the same
  /// value, just potentially different types.
  bool hasAllZeroIndices() const {
    for (const_op_iterator I = idx_begin(), E = idx_end(); I != E; ++I) {
      if (ConstantInt *C = dyn_cast<ConstantInt>(I))
        if (C->isZero())
          continue;
      return false;
    }
    return true;
  }

  /// hasAllConstantIndices - Return true if all of the indices of this GEP are
  /// constant integers.  If so, the result pointer and the first operand have
  /// a constant offset between them.
  bool hasAllConstantIndices() const {
    for (const_op_iterator I = idx_begin(), E = idx_end(); I != E; ++I) {
      if (!isa<ConstantInt>(I))
        return false;
    }
    return true;
  }

  /// \brief Accumulate the constant address offset of this GEP if possible.
  ///
  /// This routine accepts an APInt into which it will accumulate the constant
  /// offset of this GEP if the GEP is in fact constant. If the GEP is not
  /// all-constant, it returns false and the value of the offset APInt is
  /// undefined (it is *not* preserved!). The APInt passed into this routine
  /// must be at exactly as wide as the IntPtr type for the address space of the
  /// base GEP pointer.
  bool accumulateConstantOffset(const DataLayout &DL, APInt &Offset) const {
    assert(Offset.getBitWidth() ==
           DL.getPointerSizeInBits(getPointerAddressSpace()) &&
           "The offset must have exactly as many bits as our pointer.");

    for (gep_type_iterator GTI = gep_type_begin(this), GTE = gep_type_end(this);
         GTI != GTE; ++GTI) {
      ConstantInt *OpC = dyn_cast<ConstantInt>(GTI.getOperand());
      if (!OpC)
        return false;
      if (OpC->isZero())
        continue;

      // Handle a struct index, which adds its field offset to the pointer.
      if (StructType *STy = dyn_cast<StructType>(*GTI)) {
        unsigned ElementIdx = OpC->getZExtValue();
        const StructLayout *SL = DL.getStructLayout(STy);
        Offset += APInt(Offset.getBitWidth(),
                        SL->getElementOffset(ElementIdx));
        continue;
      }

      // For array or vector indices, scale the index by the size of the type.
      APInt Index = OpC->getValue().sextOrTrunc(Offset.getBitWidth());
      Offset += Index * APInt(Offset.getBitWidth(),
                              DL.getTypeAllocSize(GTI.getIndexedType()));
    }
    return true;
  }

};

class PtrToIntOperator
    : public ConcreteOperator<Operator, Instruction::PtrToInt> {
  friend class PtrToInt;
  friend class ConstantExpr;

public:
  Value *getPointerOperand() {
    return getOperand(0);
  }
  const Value *getPointerOperand() const {
    return getOperand(0);
  }
  static unsigned getPointerOperandIndex() {
    return 0U;                      // get index for modifying correct operand
  }

  /// getPointerOperandType - Method to return the pointer operand as a
  /// PointerType.
  Type *getPointerOperandType() const {
    return getPointerOperand()->getType();
  }

  /// getPointerAddressSpace - Method to return the address space of the
  /// pointer operand.
  unsigned getPointerAddressSpace() const {
    return cast<PointerType>(getPointerOperandType())->getAddressSpace();
  }
};


} // End llvm namespace

#endif