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ConstantRange.h
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1 //===- ConstantRange.h - Represent a range ----------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // Represent a range of possible values that may occur when the program is run
10 // for an integral value. This keeps track of a lower and upper bound for the
11 // constant, which MAY wrap around the end of the numeric range. To do this, it
12 // keeps track of a [lower, upper) bound, which specifies an interval just like
13 // STL iterators. When used with boolean values, the following are important
14 // ranges: :
15 //
16 // [F, F) = {} = Empty set
17 // [T, F) = {T}
18 // [F, T) = {F}
19 // [T, T) = {F, T} = Full set
20 //
21 // The other integral ranges use min/max values for special range values. For
22 // example, for 8-bit types, it uses:
23 // [0, 0) = {} = Empty set
24 // [255, 255) = {0..255} = Full Set
25 //
26 // Note that ConstantRange can be used to represent either signed or
27 // unsigned ranges.
28 //
29 //===----------------------------------------------------------------------===//
30 
31 #ifndef LLVM_IR_CONSTANTRANGE_H
32 #define LLVM_IR_CONSTANTRANGE_H
33 
34 #include "llvm/ADT/APInt.h"
35 #include "llvm/IR/InstrTypes.h"
36 #include "llvm/IR/Instruction.h"
37 #include "llvm/Support/Compiler.h"
38 #include <cstdint>
39 
40 namespace llvm {
41 
42 class MDNode;
43 class raw_ostream;
44 struct KnownBits;
45 
46 /// This class represents a range of values.
47 class [[nodiscard]] ConstantRange {
48  APInt Lower, Upper;
49 
50  /// Create empty constant range with same bitwidth.
51  ConstantRange getEmpty() const {
52  return ConstantRange(getBitWidth(), false);
53  }
54 
55  /// Create full constant range with same bitwidth.
56  ConstantRange getFull() const {
57  return ConstantRange(getBitWidth(), true);
58  }
59 
60 public:
61  /// Initialize a full or empty set for the specified bit width.
62  explicit ConstantRange(uint32_t BitWidth, bool isFullSet);
63 
64  /// Initialize a range to hold the single specified value.
66 
67  /// Initialize a range of values explicitly. This will assert out if
68  /// Lower==Upper and Lower != Min or Max value for its type. It will also
69  /// assert out if the two APInt's are not the same bit width.
71 
72  /// Create empty constant range with the given bit width.
74  return ConstantRange(BitWidth, false);
75  }
76 
77  /// Create full constant range with the given bit width.
79  return ConstantRange(BitWidth, true);
80  }
81 
82  /// Create non-empty constant range with the given bounds. If Lower and
83  /// Upper are the same, a full range is returned.
84  static ConstantRange getNonEmpty(APInt Lower, APInt Upper) {
85  if (Lower == Upper)
86  return getFull(Lower.getBitWidth());
87  return ConstantRange(std::move(Lower), std::move(Upper));
88  }
89 
90  /// Initialize a range based on a known bits constraint. The IsSigned flag
91  /// indicates whether the constant range should not wrap in the signed or
92  /// unsigned domain.
93  static ConstantRange fromKnownBits(const KnownBits &Known, bool IsSigned);
94 
95  /// Produce the smallest range such that all values that may satisfy the given
96  /// predicate with any value contained within Other is contained in the
97  /// returned range. Formally, this returns a superset of
98  /// 'union over all y in Other . { x : icmp op x y is true }'. If the exact
99  /// answer is not representable as a ConstantRange, the return value will be a
100  /// proper superset of the above.
101  ///
102  /// Example: Pred = ult and Other = i8 [2, 5) returns Result = [0, 4)
103  static ConstantRange makeAllowedICmpRegion(CmpInst::Predicate Pred,
104  const ConstantRange &Other);
105 
106  /// Produce the largest range such that all values in the returned range
107  /// satisfy the given predicate with all values contained within Other.
108  /// Formally, this returns a subset of
109  /// 'intersection over all y in Other . { x : icmp op x y is true }'. If the
110  /// exact answer is not representable as a ConstantRange, the return value
111  /// will be a proper subset of the above.
112  ///
113  /// Example: Pred = ult and Other = i8 [2, 5) returns [0, 2)
114  static ConstantRange makeSatisfyingICmpRegion(CmpInst::Predicate Pred,
115  const ConstantRange &Other);
116 
117  /// Produce the exact range such that all values in the returned range satisfy
118  /// the given predicate with any value contained within Other. Formally, this
119  /// returns the exact answer when the superset of 'union over all y in Other
120  /// is exactly same as the subset of intersection over all y in Other.
121  /// { x : icmp op x y is true}'.
122  ///
123  /// Example: Pred = ult and Other = i8 3 returns [0, 3)
124  static ConstantRange makeExactICmpRegion(CmpInst::Predicate Pred,
125  const APInt &Other);
126 
127  /// Does the predicate \p Pred hold between ranges this and \p Other?
128  /// NOTE: false does not mean that inverse predicate holds!
129  bool icmp(CmpInst::Predicate Pred, const ConstantRange &Other) const;
130 
131  /// Return true iff CR1 ult CR2 is equivalent to CR1 slt CR2.
132  /// Does not depend on strictness/direction of the predicate.
133  static bool
134  areInsensitiveToSignednessOfICmpPredicate(const ConstantRange &CR1,
135  const ConstantRange &CR2);
136 
137  /// Return true iff CR1 ult CR2 is equivalent to CR1 sge CR2.
138  /// Does not depend on strictness/direction of the predicate.
139  static bool
140  areInsensitiveToSignednessOfInvertedICmpPredicate(const ConstantRange &CR1,
141  const ConstantRange &CR2);
142 
143  /// If the comparison between constant ranges this and Other
144  /// is insensitive to the signedness of the comparison predicate,
145  /// return a predicate equivalent to \p Pred, with flipped signedness
146  /// (i.e. unsigned instead of signed or vice versa), and maybe inverted,
147  /// otherwise returns CmpInst::Predicate::BAD_ICMP_PREDICATE.
148  static CmpInst::Predicate
149  getEquivalentPredWithFlippedSignedness(CmpInst::Predicate Pred,
150  const ConstantRange &CR1,
151  const ConstantRange &CR2);
152 
153  /// Produce the largest range containing all X such that "X BinOp Y" is
154  /// guaranteed not to wrap (overflow) for *all* Y in Other. However, there may
155  /// be *some* Y in Other for which additional X not contained in the result
156  /// also do not overflow.
157  ///
158  /// NoWrapKind must be one of OBO::NoUnsignedWrap or OBO::NoSignedWrap.
159  ///
160  /// Examples:
161  /// typedef OverflowingBinaryOperator OBO;
162  /// #define MGNR makeGuaranteedNoWrapRegion
163  /// MGNR(Add, [i8 1, 2), OBO::NoSignedWrap) == [-128, 127)
164  /// MGNR(Add, [i8 1, 2), OBO::NoUnsignedWrap) == [0, -1)
165  /// MGNR(Add, [i8 0, 1), OBO::NoUnsignedWrap) == Full Set
166  /// MGNR(Add, [i8 -1, 6), OBO::NoSignedWrap) == [INT_MIN+1, INT_MAX-4)
167  /// MGNR(Sub, [i8 1, 2), OBO::NoSignedWrap) == [-127, 128)
168  /// MGNR(Sub, [i8 1, 2), OBO::NoUnsignedWrap) == [1, 0)
169  static ConstantRange makeGuaranteedNoWrapRegion(Instruction::BinaryOps BinOp,
170  const ConstantRange &Other,
171  unsigned NoWrapKind);
172 
173  /// Produce the range that contains X if and only if "X BinOp Other" does
174  /// not wrap.
175  static ConstantRange makeExactNoWrapRegion(Instruction::BinaryOps BinOp,
176  const APInt &Other,
177  unsigned NoWrapKind);
178 
179  /// Returns true if ConstantRange calculations are supported for intrinsic
180  /// with \p IntrinsicID.
181  static bool isIntrinsicSupported(Intrinsic::ID IntrinsicID);
182 
183  /// Compute range of intrinsic result for the given operand ranges.
184  static ConstantRange intrinsic(Intrinsic::ID IntrinsicID,
186 
187  /// Set up \p Pred and \p RHS such that
188  /// ConstantRange::makeExactICmpRegion(Pred, RHS) == *this. Return true if
189  /// successful.
190  bool getEquivalentICmp(CmpInst::Predicate &Pred, APInt &RHS) const;
191 
192  /// Set up \p Pred, \p RHS and \p Offset such that (V + Offset) Pred RHS
193  /// is true iff V is in the range. Prefers using Offset == 0 if possible.
194  void
195  getEquivalentICmp(CmpInst::Predicate &Pred, APInt &RHS, APInt &Offset) const;
196 
197  /// Return the lower value for this range.
198  const APInt &getLower() const { return Lower; }
199 
200  /// Return the upper value for this range.
201  const APInt &getUpper() const { return Upper; }
202 
203  /// Get the bit width of this ConstantRange.
204  uint32_t getBitWidth() const { return Lower.getBitWidth(); }
205 
206  /// Return true if this set contains all of the elements possible
207  /// for this data-type.
208  bool isFullSet() const;
209 
210  /// Return true if this set contains no members.
211  bool isEmptySet() const;
212 
213  /// Return true if this set wraps around the unsigned domain. Special cases:
214  /// * Empty set: Not wrapped.
215  /// * Full set: Not wrapped.
216  /// * [X, 0) == [X, Max]: Not wrapped.
217  bool isWrappedSet() const;
218 
219  /// Return true if the exclusive upper bound wraps around the unsigned
220  /// domain. Special cases:
221  /// * Empty set: Not wrapped.
222  /// * Full set: Not wrapped.
223  /// * [X, 0): Wrapped.
224  bool isUpperWrapped() const;
225 
226  /// Return true if this set wraps around the signed domain. Special cases:
227  /// * Empty set: Not wrapped.
228  /// * Full set: Not wrapped.
229  /// * [X, SignedMin) == [X, SignedMax]: Not wrapped.
230  bool isSignWrappedSet() const;
231 
232  /// Return true if the (exclusive) upper bound wraps around the signed
233  /// domain. Special cases:
234  /// * Empty set: Not wrapped.
235  /// * Full set: Not wrapped.
236  /// * [X, SignedMin): Wrapped.
237  bool isUpperSignWrapped() const;
238 
239  /// Return true if the specified value is in the set.
240  bool contains(const APInt &Val) const;
241 
242  /// Return true if the other range is a subset of this one.
243  bool contains(const ConstantRange &CR) const;
244 
245  /// If this set contains a single element, return it, otherwise return null.
246  const APInt *getSingleElement() const {
247  if (Upper == Lower + 1)
248  return &Lower;
249  return nullptr;
250  }
251 
252  /// If this set contains all but a single element, return it, otherwise return
253  /// null.
255  if (Lower == Upper + 1)
256  return &Upper;
257  return nullptr;
258  }
259 
260  /// Return true if this set contains exactly one member.
261  bool isSingleElement() const { return getSingleElement() != nullptr; }
262 
263  /// Compare set size of this range with the range CR.
264  bool isSizeStrictlySmallerThan(const ConstantRange &CR) const;
265 
266  /// Compare set size of this range with Value.
267  bool isSizeLargerThan(uint64_t MaxSize) const;
268 
269  /// Return true if all values in this range are negative.
270  bool isAllNegative() const;
271 
272  /// Return true if all values in this range are non-negative.
273  bool isAllNonNegative() const;
274 
275  /// Return the largest unsigned value contained in the ConstantRange.
276  APInt getUnsignedMax() const;
277 
278  /// Return the smallest unsigned value contained in the ConstantRange.
279  APInt getUnsignedMin() const;
280 
281  /// Return the largest signed value contained in the ConstantRange.
282  APInt getSignedMax() const;
283 
284  /// Return the smallest signed value contained in the ConstantRange.
285  APInt getSignedMin() const;
286 
287  /// Return true if this range is equal to another range.
288  bool operator==(const ConstantRange &CR) const {
289  return Lower == CR.Lower && Upper == CR.Upper;
290  }
291  bool operator!=(const ConstantRange &CR) const {
292  return !operator==(CR);
293  }
294 
295  /// Compute the maximal number of active bits needed to represent every value
296  /// in this range.
297  unsigned getActiveBits() const;
298 
299  /// Compute the maximal number of bits needed to represent every value
300  /// in this signed range.
301  unsigned getMinSignedBits() const;
302 
303  /// Subtract the specified constant from the endpoints of this constant range.
304  ConstantRange subtract(const APInt &CI) const;
305 
306  /// Subtract the specified range from this range (aka relative complement of
307  /// the sets).
308  ConstantRange difference(const ConstantRange &CR) const;
309 
310  /// If represented precisely, the result of some range operations may consist
311  /// of multiple disjoint ranges. As only a single range may be returned, any
312  /// range covering these disjoint ranges constitutes a valid result, but some
313  /// may be more useful than others depending on context. The preferred range
314  /// type specifies whether a range that is non-wrapping in the unsigned or
315  /// signed domain, or has the smallest size, is preferred. If a signedness is
316  /// preferred but all ranges are non-wrapping or all wrapping, then the
317  /// smallest set size is preferred. If there are multiple smallest sets, any
318  /// one of them may be returned.
319  enum PreferredRangeType { Smallest, Unsigned, Signed };
320 
321  /// Return the range that results from the intersection of this range with
322  /// another range. If the intersection is disjoint, such that two results
323  /// are possible, the preferred range is determined by the PreferredRangeType.
324  ConstantRange intersectWith(const ConstantRange &CR,
325  PreferredRangeType Type = Smallest) const;
326 
327  /// Return the range that results from the union of this range
328  /// with another range. The resultant range is guaranteed to include the
329  /// elements of both sets, but may contain more. For example, [3, 9) union
330  /// [12,15) is [3, 15), which includes 9, 10, and 11, which were not included
331  /// in either set before.
332  ConstantRange unionWith(const ConstantRange &CR,
333  PreferredRangeType Type = Smallest) const;
334 
335  /// Intersect the two ranges and return the result if it can be represented
336  /// exactly, otherwise return None.
337  Optional<ConstantRange> exactIntersectWith(const ConstantRange &CR) const;
338 
339  /// Union the two ranges and return the result if it can be represented
340  /// exactly, otherwise return None.
341  Optional<ConstantRange> exactUnionWith(const ConstantRange &CR) const;
342 
343  /// Return a new range representing the possible values resulting
344  /// from an application of the specified cast operator to this range. \p
345  /// BitWidth is the target bitwidth of the cast. For casts which don't
346  /// change bitwidth, it must be the same as the source bitwidth. For casts
347  /// which do change bitwidth, the bitwidth must be consistent with the
348  /// requested cast and source bitwidth.
349  ConstantRange castOp(Instruction::CastOps CastOp,
350  uint32_t BitWidth) const;
351 
352  /// Return a new range in the specified integer type, which must
353  /// be strictly larger than the current type. The returned range will
354  /// correspond to the possible range of values if the source range had been
355  /// zero extended to BitWidth.
356  ConstantRange zeroExtend(uint32_t BitWidth) const;
357 
358  /// Return a new range in the specified integer type, which must
359  /// be strictly larger than the current type. The returned range will
360  /// correspond to the possible range of values if the source range had been
361  /// sign extended to BitWidth.
362  ConstantRange signExtend(uint32_t BitWidth) const;
363 
364  /// Return a new range in the specified integer type, which must be
365  /// strictly smaller than the current type. The returned range will
366  /// correspond to the possible range of values if the source range had been
367  /// truncated to the specified type.
368  ConstantRange truncate(uint32_t BitWidth) const;
369 
370  /// Make this range have the bit width given by \p BitWidth. The
371  /// value is zero extended, truncated, or left alone to make it that width.
372  ConstantRange zextOrTrunc(uint32_t BitWidth) const;
373 
374  /// Make this range have the bit width given by \p BitWidth. The
375  /// value is sign extended, truncated, or left alone to make it that width.
376  ConstantRange sextOrTrunc(uint32_t BitWidth) const;
377 
378  /// Return a new range representing the possible values resulting
379  /// from an application of the specified binary operator to an left hand side
380  /// of this range and a right hand side of \p Other.
381  ConstantRange binaryOp(Instruction::BinaryOps BinOp,
382  const ConstantRange &Other) const;
383 
384  /// Return a new range representing the possible values resulting
385  /// from an application of the specified overflowing binary operator to a
386  /// left hand side of this range and a right hand side of \p Other given
387  /// the provided knowledge about lack of wrapping \p NoWrapKind.
388  ConstantRange overflowingBinaryOp(Instruction::BinaryOps BinOp,
389  const ConstantRange &Other,
390  unsigned NoWrapKind) const;
391 
392  /// Return a new range representing the possible values resulting
393  /// from an addition of a value in this range and a value in \p Other.
394  ConstantRange add(const ConstantRange &Other) const;
395 
396  /// Return a new range representing the possible values resulting
397  /// from an addition with wrap type \p NoWrapKind of a value in this
398  /// range and a value in \p Other.
399  /// If the result range is disjoint, the preferred range is determined by the
400  /// \p PreferredRangeType.
401  ConstantRange addWithNoWrap(const ConstantRange &Other, unsigned NoWrapKind,
402  PreferredRangeType RangeType = Smallest) const;
403 
404  /// Return a new range representing the possible values resulting
405  /// from a subtraction of a value in this range and a value in \p Other.
406  ConstantRange sub(const ConstantRange &Other) const;
407 
408  /// Return a new range representing the possible values resulting
409  /// from an subtraction with wrap type \p NoWrapKind of a value in this
410  /// range and a value in \p Other.
411  /// If the result range is disjoint, the preferred range is determined by the
412  /// \p PreferredRangeType.
413  ConstantRange subWithNoWrap(const ConstantRange &Other, unsigned NoWrapKind,
414  PreferredRangeType RangeType = Smallest) const;
415 
416  /// Return a new range representing the possible values resulting
417  /// from a multiplication of a value in this range and a value in \p Other,
418  /// treating both this and \p Other as unsigned ranges.
419  ConstantRange multiply(const ConstantRange &Other) const;
420 
421  /// Return range of possible values for a signed multiplication of this and
422  /// \p Other. However, if overflow is possible always return a full range
423  /// rather than trying to determine a more precise result.
424  ConstantRange smul_fast(const ConstantRange &Other) const;
425 
426  /// Return a new range representing the possible values resulting
427  /// from a signed maximum of a value in this range and a value in \p Other.
428  ConstantRange smax(const ConstantRange &Other) const;
429 
430  /// Return a new range representing the possible values resulting
431  /// from an unsigned maximum of a value in this range and a value in \p Other.
432  ConstantRange umax(const ConstantRange &Other) const;
433 
434  /// Return a new range representing the possible values resulting
435  /// from a signed minimum of a value in this range and a value in \p Other.
436  ConstantRange smin(const ConstantRange &Other) const;
437 
438  /// Return a new range representing the possible values resulting
439  /// from an unsigned minimum of a value in this range and a value in \p Other.
440  ConstantRange umin(const ConstantRange &Other) const;
441 
442  /// Return a new range representing the possible values resulting
443  /// from an unsigned division of a value in this range and a value in
444  /// \p Other.
445  ConstantRange udiv(const ConstantRange &Other) const;
446 
447  /// Return a new range representing the possible values resulting
448  /// from a signed division of a value in this range and a value in
449  /// \p Other. Division by zero and division of SignedMin by -1 are considered
450  /// undefined behavior, in line with IR, and do not contribute towards the
451  /// result.
452  ConstantRange sdiv(const ConstantRange &Other) const;
453 
454  /// Return a new range representing the possible values resulting
455  /// from an unsigned remainder operation of a value in this range and a
456  /// value in \p Other.
457  ConstantRange urem(const ConstantRange &Other) const;
458 
459  /// Return a new range representing the possible values resulting
460  /// from a signed remainder operation of a value in this range and a
461  /// value in \p Other.
462  ConstantRange srem(const ConstantRange &Other) const;
463 
464  /// Return a new range representing the possible values resulting from
465  /// a binary-xor of a value in this range by an all-one value,
466  /// aka bitwise complement operation.
467  ConstantRange binaryNot() const;
468 
469  /// Return a new range representing the possible values resulting
470  /// from a binary-and of a value in this range by a value in \p Other.
471  ConstantRange binaryAnd(const ConstantRange &Other) const;
472 
473  /// Return a new range representing the possible values resulting
474  /// from a binary-or of a value in this range by a value in \p Other.
475  ConstantRange binaryOr(const ConstantRange &Other) const;
476 
477  /// Return a new range representing the possible values resulting
478  /// from a binary-xor of a value in this range by a value in \p Other.
479  ConstantRange binaryXor(const ConstantRange &Other) const;
480 
481  /// Return a new range representing the possible values resulting
482  /// from a left shift of a value in this range by a value in \p Other.
483  /// TODO: This isn't fully implemented yet.
484  ConstantRange shl(const ConstantRange &Other) const;
485 
486  /// Return a new range representing the possible values resulting from a
487  /// logical right shift of a value in this range and a value in \p Other.
488  ConstantRange lshr(const ConstantRange &Other) const;
489 
490  /// Return a new range representing the possible values resulting from a
491  /// arithmetic right shift of a value in this range and a value in \p Other.
492  ConstantRange ashr(const ConstantRange &Other) const;
493 
494  /// Perform an unsigned saturating addition of two constant ranges.
495  ConstantRange uadd_sat(const ConstantRange &Other) const;
496 
497  /// Perform a signed saturating addition of two constant ranges.
498  ConstantRange sadd_sat(const ConstantRange &Other) const;
499 
500  /// Perform an unsigned saturating subtraction of two constant ranges.
501  ConstantRange usub_sat(const ConstantRange &Other) const;
502 
503  /// Perform a signed saturating subtraction of two constant ranges.
504  ConstantRange ssub_sat(const ConstantRange &Other) const;
505 
506  /// Perform an unsigned saturating multiplication of two constant ranges.
507  ConstantRange umul_sat(const ConstantRange &Other) const;
508 
509  /// Perform a signed saturating multiplication of two constant ranges.
510  ConstantRange smul_sat(const ConstantRange &Other) const;
511 
512  /// Perform an unsigned saturating left shift of this constant range by a
513  /// value in \p Other.
514  ConstantRange ushl_sat(const ConstantRange &Other) const;
515 
516  /// Perform a signed saturating left shift of this constant range by a
517  /// value in \p Other.
518  ConstantRange sshl_sat(const ConstantRange &Other) const;
519 
520  /// Return a new range that is the logical not of the current set.
521  ConstantRange inverse() const;
522 
523  /// Calculate absolute value range. If the original range contains signed
524  /// min, then the resulting range will contain signed min if and only if
525  /// \p IntMinIsPoison is false.
526  ConstantRange abs(bool IntMinIsPoison = false) const;
527 
528  /// Represents whether an operation on the given constant range is known to
529  /// always or never overflow.
530  enum class OverflowResult {
531  /// Always overflows in the direction of signed/unsigned min value.
533  /// Always overflows in the direction of signed/unsigned max value.
535  /// May or may not overflow.
536  MayOverflow,
537  /// Never overflows.
539  };
540 
541  /// Return whether unsigned add of the two ranges always/never overflows.
542  OverflowResult unsignedAddMayOverflow(const ConstantRange &Other) const;
543 
544  /// Return whether signed add of the two ranges always/never overflows.
545  OverflowResult signedAddMayOverflow(const ConstantRange &Other) const;
546 
547  /// Return whether unsigned sub of the two ranges always/never overflows.
548  OverflowResult unsignedSubMayOverflow(const ConstantRange &Other) const;
549 
550  /// Return whether signed sub of the two ranges always/never overflows.
551  OverflowResult signedSubMayOverflow(const ConstantRange &Other) const;
552 
553  /// Return whether unsigned mul of the two ranges always/never overflows.
554  OverflowResult unsignedMulMayOverflow(const ConstantRange &Other) const;
555 
556  /// Return known bits for values in this range.
557  KnownBits toKnownBits() const;
558 
559  /// Print out the bounds to a stream.
560  void print(raw_ostream &OS) const;
561 
562  /// Allow printing from a debugger easily.
563  void dump() const;
564 };
565 
567  CR.print(OS);
568  return OS;
569 }
570 
571 /// Parse out a conservative ConstantRange from !range metadata.
572 ///
573 /// E.g. if RangeMD is !{i32 0, i32 10, i32 15, i32 20} then return [0, 20).
574 ConstantRange getConstantRangeFromMetadata(const MDNode &RangeMD);
575 
576 } // end namespace llvm
577 
578 #endif // LLVM_IR_CONSTANTRANGE_H
Signed
@ Signed
Definition: NVPTXISelLowering.cpp:4715
llvm
This is an optimization pass for GlobalISel generic memory operations.
Definition: AddressRanges.h:18
intrinsic
QP Compare Ordered outs ins xscmpudp No intrinsic
Definition: README_P9.txt:303
llvm::OverflowResult::NeverOverflows
@ NeverOverflows
Never overflows.
llvm::HexPrintStyle::Upper
@ Upper
llvm::CmpInst::Predicate
Predicate
This enumeration lists the possible predicates for CmpInst subclasses.
Definition: InstrTypes.h:720
contains
return AArch64::GPR64RegClass contains(Reg)
APInt.h
llvm::Type
The instances of the Type class are immutable: once they are created, they are never changed.
Definition: Type.h:45
llvm::OverflowResult::AlwaysOverflowsLow
@ AlwaysOverflowsLow
Always overflows in the direction of signed/unsigned min value.
llvm::Optional
Definition: APInt.h:33
getBitWidth
static unsigned getBitWidth(Type *Ty, const DataLayout &DL)
Returns the bitwidth of the given scalar or pointer type.
Definition: ValueTracking.cpp:100
llvm::dump
void dump(const SparseBitVector< ElementSize > &LHS, raw_ostream &out)
Definition: SparseBitVector.h:877
RHS
Value * RHS
Definition: X86PartialReduction.cpp:76
llvm::getConstantRangeFromMetadata
ConstantRange getConstantRangeFromMetadata(const MDNode &RangeMD)
Parse out a conservative ConstantRange from !range metadata.
Definition: ConstantRange.cpp:1800
llvm::APIntOps::umin
const APInt & umin(const APInt &A, const APInt &B)
Determine the smaller of two APInts considered to be unsigned.
Definition: APInt.h:2157
llvm::ConstantRange::OverflowResult
OverflowResult
Represents whether an operation on the given constant range is known to always or never overflow.
Definition: ConstantRange.h:530
Instruction.h
shl
We currently generate a but we really shouldn eax ecx xorl edx divl ecx eax divl ecx movl eax ret A similar code sequence works for division We currently compile i32 v2 eax eax jo LBB1_2 shl
Definition: README.txt:1271
llvm::OverflowResult::MayOverflow
@ MayOverflow
May or may not overflow.
InstrTypes.h
llvm::ConstantRange::PreferredRangeType
PreferredRangeType
If represented precisely, the result of some range operations may consist of multiple disjoint ranges...
Definition: ConstantRange.h:319
llvm::ConstantRange::isSingleElement
bool isSingleElement() const
Return true if this set contains exactly one member.
Definition: ConstantRange.h:261
llvm::Instruction::CastOps
CastOps
Definition: Instruction.h:807
llvm::raw_ostream
This class implements an extremely fast bulk output stream that can only output to a stream.
Definition: raw_ostream.h:53
llvm::operator<<
raw_ostream & operator<<(raw_ostream &OS, const APFixedPoint &FX)
Definition: APFixedPoint.h:291
llvm::ConstantRange::Unsigned
@ Unsigned
Definition: ConstantRange.h:319
llvm::ConstantRange::getEmpty
static ConstantRange getEmpty(uint32_t BitWidth)
Create empty constant range with the given bit width.
Definition: ConstantRange.h:73
llvm::OverflowResult
OverflowResult
Definition: ValueTracking.h:501
llvm::ConstantRange::getBitWidth
uint32_t getBitWidth() const
Get the bit width of this ConstantRange.
Definition: ConstantRange.h:204
uint64_t
llvm::ARM_AM::add
@ add
Definition: ARMAddressingModes.h:39
move
compiles ldr LCPI1_0 ldr ldr mov lsr tst moveq r1 ldr LCPI1_1 and r0 bx lr It would be better to do something like to fold the shift into the conditional move
Definition: README.txt:546
sub
we currently eax ecx subl eax ret We would use one fewer register if codegen d eax neg eax eax ret Note that this isn t beneficial if the load can be folded into the sub In this we want a sub
Definition: README.txt:460
llvm::operator==
bool operator==(uint64_t V1, const APInt &V2)
Definition: APInt.h:2010
llvm::ConstantRange::getFull
static ConstantRange getFull(uint32_t BitWidth)
Create full constant range with the given bit width.
Definition: ConstantRange.h:78
llvm::APInt
Class for arbitrary precision integers.
Definition: APInt.h:75
llvm::ConstantRange::getSingleElement
const APInt * getSingleElement() const
If this set contains a single element, return it, otherwise return null.
Definition: ConstantRange.h:246
llvm::print
Printable print(const GCNRegPressure &RP, const GCNSubtarget *ST=nullptr)
Definition: GCNRegPressure.cpp:138
llvm::APIntOps::smin
const APInt & smin(const APInt &A, const APInt &B)
Determine the smaller of two APInts considered to be signed.
Definition: APInt.h:2147
llvm::ArrayRef
ArrayRef - Represent a constant reference to an array (0 or more elements consecutively in memory),...
Definition: APInt.h:32
uint32_t
Compiler.h
llvm::APIntOps::umax
const APInt & umax(const APInt &A, const APInt &B)
Determine the larger of two APInts considered to be unsigned.
Definition: APInt.h:2162
llvm::ConstantRange::getLower
const APInt & getLower() const
Return the lower value for this range.
Definition: ConstantRange.h:198
llvm::KnownBits
Definition: KnownBits.h:23
llvm::ConstantRange::operator==
bool operator==(const ConstantRange &CR) const
Return true if this range is equal to another range.
Definition: ConstantRange.h:288
llvm::BitWidth
constexpr unsigned BitWidth
Definition: BitmaskEnum.h:147
llvm::OverflowResult::AlwaysOverflowsHigh
@ AlwaysOverflowsHigh
Always overflows in the direction of signed/unsigned max value.
llvm::ConstantRange::getSingleMissingElement
const APInt * getSingleMissingElement() const
If this set contains all but a single element, return it, otherwise return null.
Definition: ConstantRange.h:254
llvm::ConstantRange
This class represents a range of values.
Definition: ConstantRange.h:47
llvm::ConstantRange::getNonEmpty
static ConstantRange getNonEmpty(APInt Lower, APInt Upper)
Create non-empty constant range with the given bounds.
Definition: ConstantRange.h:84
llvm::Instruction::BinaryOps
BinaryOps
Definition: Instruction.h:793
llvm::ConstantRange::print
void print(raw_ostream &OS) const
Print out the bounds to a stream.
Definition: ConstantRange.cpp:1785
lshr
Vector Shift Left don t map to llvm shl and lshr
Definition: README_P9.txt:118
llvm::abs
APFloat abs(APFloat X)
Returns the absolute value of the argument.
Definition: APFloat.h:1297
llvm::ConstantRange::getUpper
const APInt & getUpper() const
Return the upper value for this range.
Definition: ConstantRange.h:201
llvm::Value
LLVM Value Representation.
Definition: Value.h:74
llvm::APIntOps::smax
const APInt & smax(const APInt &A, const APInt &B)
Determine the larger of two APInts considered to be signed.
Definition: APInt.h:2152
llvm::ConstantRange::operator!=
bool operator!=(const ConstantRange &CR) const
Definition: ConstantRange.h:291
llvm::Intrinsic::ID
unsigned ID
Definition: TargetTransformInfo.h:39