1 //===- ConstantRangeTest.cpp - ConstantRange tests ------------------------===//
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 #include "llvm/IR/ConstantRange.h"
10 #include "llvm/ADT/BitVector.h"
11 #include "llvm/ADT/Sequence.h"
12 #include "llvm/ADT/SmallBitVector.h"
13 #include "llvm/IR/Instructions.h"
14 #include "llvm/IR/Operator.h"
15 #include "llvm/Support/KnownBits.h"
16 #include "gtest/gtest.h"
17 
18 using namespace llvm;
19 
20 namespace {
21 
22 class ConstantRangeTest : public ::testing::Test {
23 protected:
24   static ConstantRange Full;
25   static ConstantRange Empty;
26   static ConstantRange One;
27   static ConstantRange Some;
28   static ConstantRange Wrap;
29 };
30 
31 template<typename Fn>
32 static void EnumerateAPInts(unsigned Bits, Fn TestFn) {
33   APInt N(Bits, 0);
34   do {
35     TestFn(N);
36   } while (++N != 0);
37 }
38 
39 template<typename Fn>
40 static void EnumerateConstantRanges(unsigned Bits, Fn TestFn) {
41   unsigned Max = 1 << Bits;
42   for (unsigned Lo = 0; Lo < Max; Lo++) {
43     for (unsigned Hi = 0; Hi < Max; Hi++) {
44       // Enforce ConstantRange invariant.
45       if (Lo == Hi && Lo != 0 && Lo != Max - 1)
46         continue;
47 
48       ConstantRange CR(APInt(Bits, Lo), APInt(Bits, Hi));
49       TestFn(CR);
50     }
51   }
52 }
53 
54 template<typename Fn>
55 static void EnumerateTwoConstantRanges(unsigned Bits, Fn TestFn) {
56   EnumerateConstantRanges(Bits, [&](const ConstantRange &CR1) {
57     EnumerateConstantRanges(Bits, [&](const ConstantRange &CR2) {
58       TestFn(CR1, CR2);
59     });
60   });
61 }
62 
63 template<typename Fn>
64 static void ForeachNumInConstantRange(const ConstantRange &CR, Fn TestFn) {
65   if (!CR.isEmptySet()) {
66     APInt N = CR.getLower();
67     do TestFn(N);
68     while (++N != CR.getUpper());
69   }
70 }
71 
72 using PreferFn = llvm::function_ref<bool(const ConstantRange &,
73                                          const ConstantRange &)>;
74 
75 bool PreferSmallest(const ConstantRange &CR1, const ConstantRange &CR2) {
76   return CR1.isSizeStrictlySmallerThan(CR2);
77 }
78 
79 bool PreferSmallestUnsigned(const ConstantRange &CR1,
80                             const ConstantRange &CR2) {
81   if (CR1.isWrappedSet() != CR2.isWrappedSet())
82     return CR1.isWrappedSet() < CR2.isWrappedSet();
83   return PreferSmallest(CR1, CR2);
84 }
85 
86 bool PreferSmallestSigned(const ConstantRange &CR1, const ConstantRange &CR2) {
87   if (CR1.isSignWrappedSet() != CR2.isSignWrappedSet())
88     return CR1.isSignWrappedSet() < CR2.isSignWrappedSet();
89   return PreferSmallest(CR1, CR2);
90 }
91 
92 bool PreferSmallestNonFullUnsigned(const ConstantRange &CR1,
93                                    const ConstantRange &CR2) {
94   if (CR1.isFullSet() != CR2.isFullSet())
95     return CR1.isFullSet() < CR2.isFullSet();
96   return PreferSmallestUnsigned(CR1, CR2);
97 }
98 
99 bool PreferSmallestNonFullSigned(const ConstantRange &CR1,
100                                  const ConstantRange &CR2) {
101   if (CR1.isFullSet() != CR2.isFullSet())
102     return CR1.isFullSet() < CR2.isFullSet();
103   return PreferSmallestSigned(CR1, CR2);
104 }
105 
106 testing::AssertionResult rangeContains(const ConstantRange &CR, const APInt &N,
107                                        ArrayRef<ConstantRange> Inputs) {
108   if (CR.contains(N))
109     return testing::AssertionSuccess();
110 
111   testing::AssertionResult Result = testing::AssertionFailure();
112   Result << CR << " does not contain " << N << " for inputs: ";
113   for (const ConstantRange &Input : Inputs)
114     Result << Input << ", ";
115   return Result;
116 }
117 
118 // Check whether constant range CR is an optimal approximation of the set
119 // Elems under the given PreferenceFn. The preference function should return
120 // true if the first range argument is strictly preferred to the second one.
121 static void TestRange(const ConstantRange &CR, const SmallBitVector &Elems,
122                       PreferFn PreferenceFn, ArrayRef<ConstantRange> Inputs,
123                       bool CheckOptimality = true) {
124   unsigned BitWidth = CR.getBitWidth();
125 
126   // Check conservative correctness.
127   for (unsigned Elem : Elems.set_bits()) {
128     EXPECT_TRUE(rangeContains(CR, APInt(BitWidth, Elem), Inputs));
129   }
130 
131   if (!CheckOptimality)
132     return;
133 
134   // Make sure we have at least one element for the code below.
135   if (Elems.none()) {
136     EXPECT_TRUE(CR.isEmptySet());
137     return;
138   }
139 
140   auto NotPreferred = [&](const ConstantRange &PossibleCR) {
141     if (!PreferenceFn(PossibleCR, CR))
142       return testing::AssertionSuccess();
143 
144     testing::AssertionResult Result = testing::AssertionFailure();
145     Result << "Inputs = ";
146     for (const ConstantRange &Input : Inputs)
147       Result << Input << ", ";
148     Result << "CR = " << CR << ", BetterCR = " << PossibleCR;
149     return Result;
150   };
151 
152   // Look at all pairs of adjacent elements and the slack-free ranges
153   // [Elem, PrevElem] they imply. Check that none of the ranges are strictly
154   // preferred over the computed range (they may have equal preference).
155   int FirstElem = Elems.find_first();
156   int PrevElem = FirstElem, Elem;
157   do {
158     Elem = Elems.find_next(PrevElem);
159     if (Elem < 0)
160       Elem = FirstElem; // Wrap around to first element.
161 
162     ConstantRange PossibleCR =
163         ConstantRange::getNonEmpty(APInt(BitWidth, Elem),
164                                    APInt(BitWidth, PrevElem) + 1);
165     // We get a full range any time PrevElem and Elem are adjacent. Avoid
166     // repeated checks by skipping here, and explicitly checking below instead.
167     if (!PossibleCR.isFullSet()) {
168       EXPECT_TRUE(NotPreferred(PossibleCR));
169     }
170 
171     PrevElem = Elem;
172   } while (Elem != FirstElem);
173 
174   EXPECT_TRUE(NotPreferred(ConstantRange::getFull(BitWidth)));
175 }
176 
177 using UnaryRangeFn = llvm::function_ref<ConstantRange(const ConstantRange &)>;
178 using UnaryIntFn = llvm::function_ref<Optional<APInt>(const APInt &)>;
179 
180 static void TestUnaryOpExhaustive(UnaryRangeFn RangeFn, UnaryIntFn IntFn,
181                                   PreferFn PreferenceFn = PreferSmallest) {
182   unsigned Bits = 4;
183   EnumerateConstantRanges(Bits, [&](const ConstantRange &CR) {
184     SmallBitVector Elems(1 << Bits);
185     ForeachNumInConstantRange(CR, [&](const APInt &N) {
186       if (Optional<APInt> ResultN = IntFn(N))
187         Elems.set(ResultN->getZExtValue());
188     });
189     TestRange(RangeFn(CR), Elems, PreferenceFn, {CR});
190   });
191 }
192 
193 using BinaryRangeFn = llvm::function_ref<ConstantRange(const ConstantRange &,
194                                                        const ConstantRange &)>;
195 using BinaryIntFn = llvm::function_ref<Optional<APInt>(const APInt &,
196                                                        const APInt &)>;
197 using BinaryCheckFn = llvm::function_ref<bool(const ConstantRange &,
198                                               const ConstantRange &)>;
199 
200 static bool CheckAll(const ConstantRange &, const ConstantRange &) {
201   return true;
202 }
203 
204 static bool CheckSingleElementsOnly(const ConstantRange &CR1,
205                                     const ConstantRange &CR2) {
206   return CR1.isSingleElement() && CR2.isSingleElement();
207 }
208 
209 // CheckFn determines whether optimality is checked for a given range pair.
210 // Correctness is always checked.
211 static void TestBinaryOpExhaustive(BinaryRangeFn RangeFn, BinaryIntFn IntFn,
212                                    PreferFn PreferenceFn = PreferSmallest,
213                                    BinaryCheckFn CheckFn = CheckAll) {
214   unsigned Bits = 4;
215   EnumerateTwoConstantRanges(
216       Bits, [&](const ConstantRange &CR1, const ConstantRange &CR2) {
217         SmallBitVector Elems(1 << Bits);
218         ForeachNumInConstantRange(CR1, [&](const APInt &N1) {
219           ForeachNumInConstantRange(CR2, [&](const APInt &N2) {
220             if (Optional<APInt> ResultN = IntFn(N1, N2))
221               Elems.set(ResultN->getZExtValue());
222           });
223         });
224         TestRange(RangeFn(CR1, CR2), Elems, PreferenceFn, {CR1, CR2},
225                   CheckFn(CR1, CR2));
226       });
227 }
228 
229 struct OpRangeGathererBase {
230   void account(const APInt &N);
231   ConstantRange getRange();
232 };
233 
234 struct UnsignedOpRangeGatherer : public OpRangeGathererBase {
235   APInt Min;
236   APInt Max;
237 
238   UnsignedOpRangeGatherer(unsigned Bits)
239       : Min(APInt::getMaxValue(Bits)), Max(APInt::getMinValue(Bits)) {}
240 
241   void account(const APInt &N) {
242     if (N.ult(Min))
243       Min = N;
244     if (N.ugt(Max))
245       Max = N;
246   }
247 
248   ConstantRange getRange() {
249     if (Min.ugt(Max))
250       return ConstantRange::getEmpty(Min.getBitWidth());
251     return ConstantRange::getNonEmpty(Min, Max + 1);
252   }
253 };
254 
255 struct SignedOpRangeGatherer : public OpRangeGathererBase {
256   APInt Min;
257   APInt Max;
258 
259   SignedOpRangeGatherer(unsigned Bits)
260       : Min(APInt::getSignedMaxValue(Bits)),
261         Max(APInt::getSignedMinValue(Bits)) {}
262 
263   void account(const APInt &N) {
264     if (N.slt(Min))
265       Min = N;
266     if (N.sgt(Max))
267       Max = N;
268   }
269 
270   ConstantRange getRange() {
271     if (Min.sgt(Max))
272       return ConstantRange::getEmpty(Min.getBitWidth());
273     return ConstantRange::getNonEmpty(Min, Max + 1);
274   }
275 };
276 
277 ConstantRange ConstantRangeTest::Full(16, true);
278 ConstantRange ConstantRangeTest::Empty(16, false);
279 ConstantRange ConstantRangeTest::One(APInt(16, 0xa));
280 ConstantRange ConstantRangeTest::Some(APInt(16, 0xa), APInt(16, 0xaaa));
281 ConstantRange ConstantRangeTest::Wrap(APInt(16, 0xaaa), APInt(16, 0xa));
282 
283 TEST_F(ConstantRangeTest, Basics) {
284   EXPECT_TRUE(Full.isFullSet());
285   EXPECT_FALSE(Full.isEmptySet());
286   EXPECT_TRUE(Full.inverse().isEmptySet());
287   EXPECT_FALSE(Full.isWrappedSet());
288   EXPECT_TRUE(Full.contains(APInt(16, 0x0)));
289   EXPECT_TRUE(Full.contains(APInt(16, 0x9)));
290   EXPECT_TRUE(Full.contains(APInt(16, 0xa)));
291   EXPECT_TRUE(Full.contains(APInt(16, 0xaa9)));
292   EXPECT_TRUE(Full.contains(APInt(16, 0xaaa)));
293 
294   EXPECT_FALSE(Empty.isFullSet());
295   EXPECT_TRUE(Empty.isEmptySet());
296   EXPECT_TRUE(Empty.inverse().isFullSet());
297   EXPECT_FALSE(Empty.isWrappedSet());
298   EXPECT_FALSE(Empty.contains(APInt(16, 0x0)));
299   EXPECT_FALSE(Empty.contains(APInt(16, 0x9)));
300   EXPECT_FALSE(Empty.contains(APInt(16, 0xa)));
301   EXPECT_FALSE(Empty.contains(APInt(16, 0xaa9)));
302   EXPECT_FALSE(Empty.contains(APInt(16, 0xaaa)));
303 
304   EXPECT_FALSE(One.isFullSet());
305   EXPECT_FALSE(One.isEmptySet());
306   EXPECT_FALSE(One.isWrappedSet());
307   EXPECT_FALSE(One.contains(APInt(16, 0x0)));
308   EXPECT_FALSE(One.contains(APInt(16, 0x9)));
309   EXPECT_TRUE(One.contains(APInt(16, 0xa)));
310   EXPECT_FALSE(One.contains(APInt(16, 0xaa9)));
311   EXPECT_FALSE(One.contains(APInt(16, 0xaaa)));
312   EXPECT_FALSE(One.inverse().contains(APInt(16, 0xa)));
313 
314   EXPECT_FALSE(Some.isFullSet());
315   EXPECT_FALSE(Some.isEmptySet());
316   EXPECT_FALSE(Some.isWrappedSet());
317   EXPECT_FALSE(Some.contains(APInt(16, 0x0)));
318   EXPECT_FALSE(Some.contains(APInt(16, 0x9)));
319   EXPECT_TRUE(Some.contains(APInt(16, 0xa)));
320   EXPECT_TRUE(Some.contains(APInt(16, 0xaa9)));
321   EXPECT_FALSE(Some.contains(APInt(16, 0xaaa)));
322 
323   EXPECT_FALSE(Wrap.isFullSet());
324   EXPECT_FALSE(Wrap.isEmptySet());
325   EXPECT_TRUE(Wrap.isWrappedSet());
326   EXPECT_TRUE(Wrap.contains(APInt(16, 0x0)));
327   EXPECT_TRUE(Wrap.contains(APInt(16, 0x9)));
328   EXPECT_FALSE(Wrap.contains(APInt(16, 0xa)));
329   EXPECT_FALSE(Wrap.contains(APInt(16, 0xaa9)));
330   EXPECT_TRUE(Wrap.contains(APInt(16, 0xaaa)));
331 }
332 
333 TEST_F(ConstantRangeTest, Equality) {
334   EXPECT_EQ(Full, Full);
335   EXPECT_EQ(Empty, Empty);
336   EXPECT_EQ(One, One);
337   EXPECT_EQ(Some, Some);
338   EXPECT_EQ(Wrap, Wrap);
339   EXPECT_NE(Full, Empty);
340   EXPECT_NE(Full, One);
341   EXPECT_NE(Full, Some);
342   EXPECT_NE(Full, Wrap);
343   EXPECT_NE(Empty, One);
344   EXPECT_NE(Empty, Some);
345   EXPECT_NE(Empty, Wrap);
346   EXPECT_NE(One, Some);
347   EXPECT_NE(One, Wrap);
348   EXPECT_NE(Some, Wrap);
349 }
350 
351 TEST_F(ConstantRangeTest, SingleElement) {
352   EXPECT_EQ(Full.getSingleElement(), static_cast<APInt *>(nullptr));
353   EXPECT_EQ(Empty.getSingleElement(), static_cast<APInt *>(nullptr));
354   EXPECT_EQ(Full.getSingleMissingElement(), static_cast<APInt *>(nullptr));
355   EXPECT_EQ(Empty.getSingleMissingElement(), static_cast<APInt *>(nullptr));
356 
357   EXPECT_EQ(*One.getSingleElement(), APInt(16, 0xa));
358   EXPECT_EQ(Some.getSingleElement(), static_cast<APInt *>(nullptr));
359   EXPECT_EQ(Wrap.getSingleElement(), static_cast<APInt *>(nullptr));
360 
361   EXPECT_EQ(One.getSingleMissingElement(), static_cast<APInt *>(nullptr));
362   EXPECT_EQ(Some.getSingleMissingElement(), static_cast<APInt *>(nullptr));
363 
364   ConstantRange OneInverse = One.inverse();
365   EXPECT_EQ(*OneInverse.getSingleMissingElement(), *One.getSingleElement());
366 
367   EXPECT_FALSE(Full.isSingleElement());
368   EXPECT_FALSE(Empty.isSingleElement());
369   EXPECT_TRUE(One.isSingleElement());
370   EXPECT_FALSE(Some.isSingleElement());
371   EXPECT_FALSE(Wrap.isSingleElement());
372 }
373 
374 TEST_F(ConstantRangeTest, GetMinsAndMaxes) {
375   EXPECT_EQ(Full.getUnsignedMax(), APInt(16, UINT16_MAX));
376   EXPECT_EQ(One.getUnsignedMax(), APInt(16, 0xa));
377   EXPECT_EQ(Some.getUnsignedMax(), APInt(16, 0xaa9));
378   EXPECT_EQ(Wrap.getUnsignedMax(), APInt(16, UINT16_MAX));
379 
380   EXPECT_EQ(Full.getUnsignedMin(), APInt(16, 0));
381   EXPECT_EQ(One.getUnsignedMin(), APInt(16, 0xa));
382   EXPECT_EQ(Some.getUnsignedMin(), APInt(16, 0xa));
383   EXPECT_EQ(Wrap.getUnsignedMin(), APInt(16, 0));
384 
385   EXPECT_EQ(Full.getSignedMax(), APInt(16, INT16_MAX));
386   EXPECT_EQ(One.getSignedMax(), APInt(16, 0xa));
387   EXPECT_EQ(Some.getSignedMax(), APInt(16, 0xaa9));
388   EXPECT_EQ(Wrap.getSignedMax(), APInt(16, INT16_MAX));
389 
390   EXPECT_EQ(Full.getSignedMin(), APInt(16, (uint64_t)INT16_MIN));
391   EXPECT_EQ(One.getSignedMin(), APInt(16, 0xa));
392   EXPECT_EQ(Some.getSignedMin(), APInt(16, 0xa));
393   EXPECT_EQ(Wrap.getSignedMin(), APInt(16, (uint64_t)INT16_MIN));
394 
395   // Found by Klee
396   EXPECT_EQ(ConstantRange(APInt(4, 7), APInt(4, 0)).getSignedMax(),
397             APInt(4, 7));
398 }
399 
400 TEST_F(ConstantRangeTest, SignWrapped) {
401   EXPECT_FALSE(Full.isSignWrappedSet());
402   EXPECT_FALSE(Empty.isSignWrappedSet());
403   EXPECT_FALSE(One.isSignWrappedSet());
404   EXPECT_FALSE(Some.isSignWrappedSet());
405   EXPECT_TRUE(Wrap.isSignWrappedSet());
406 
407   EXPECT_FALSE(ConstantRange(APInt(8, 127), APInt(8, 128)).isSignWrappedSet());
408   EXPECT_TRUE(ConstantRange(APInt(8, 127), APInt(8, 129)).isSignWrappedSet());
409   EXPECT_FALSE(ConstantRange(APInt(8, 128), APInt(8, 129)).isSignWrappedSet());
410   EXPECT_TRUE(ConstantRange(APInt(8, 10), APInt(8, 9)).isSignWrappedSet());
411   EXPECT_TRUE(ConstantRange(APInt(8, 10), APInt(8, 250)).isSignWrappedSet());
412   EXPECT_FALSE(ConstantRange(APInt(8, 250), APInt(8, 10)).isSignWrappedSet());
413   EXPECT_FALSE(ConstantRange(APInt(8, 250), APInt(8, 251)).isSignWrappedSet());
414 }
415 
416 TEST_F(ConstantRangeTest, UpperWrapped) {
417   // The behavior here is the same as for isWrappedSet() / isSignWrappedSet().
418   EXPECT_FALSE(Full.isUpperWrapped());
419   EXPECT_FALSE(Empty.isUpperWrapped());
420   EXPECT_FALSE(One.isUpperWrapped());
421   EXPECT_FALSE(Some.isUpperWrapped());
422   EXPECT_TRUE(Wrap.isUpperWrapped());
423   EXPECT_FALSE(Full.isUpperSignWrapped());
424   EXPECT_FALSE(Empty.isUpperSignWrapped());
425   EXPECT_FALSE(One.isUpperSignWrapped());
426   EXPECT_FALSE(Some.isUpperSignWrapped());
427   EXPECT_TRUE(Wrap.isUpperSignWrapped());
428 
429   // The behavior differs if Upper is the Min/SignedMin value.
430   ConstantRange CR1(APInt(8, 42), APInt::getMinValue(8));
431   EXPECT_FALSE(CR1.isWrappedSet());
432   EXPECT_TRUE(CR1.isUpperWrapped());
433 
434   ConstantRange CR2(APInt(8, 42), APInt::getSignedMinValue(8));
435   EXPECT_FALSE(CR2.isSignWrappedSet());
436   EXPECT_TRUE(CR2.isUpperSignWrapped());
437 }
438 
439 TEST_F(ConstantRangeTest, Trunc) {
440   ConstantRange TFull = Full.truncate(10);
441   ConstantRange TEmpty = Empty.truncate(10);
442   ConstantRange TOne = One.truncate(10);
443   ConstantRange TSome = Some.truncate(10);
444   ConstantRange TWrap = Wrap.truncate(10);
445   EXPECT_TRUE(TFull.isFullSet());
446   EXPECT_TRUE(TEmpty.isEmptySet());
447   EXPECT_EQ(TOne, ConstantRange(One.getLower().trunc(10),
448                                 One.getUpper().trunc(10)));
449   EXPECT_TRUE(TSome.isFullSet());
450   EXPECT_TRUE(TWrap.isFullSet());
451 
452   // trunc([2, 5), 3->2) = [2, 1)
453   ConstantRange TwoFive(APInt(3, 2), APInt(3, 5));
454   EXPECT_EQ(TwoFive.truncate(2), ConstantRange(APInt(2, 2), APInt(2, 1)));
455 
456   // trunc([2, 6), 3->2) = full
457   ConstantRange TwoSix(APInt(3, 2), APInt(3, 6));
458   EXPECT_TRUE(TwoSix.truncate(2).isFullSet());
459 
460   // trunc([5, 7), 3->2) = [1, 3)
461   ConstantRange FiveSeven(APInt(3, 5), APInt(3, 7));
462   EXPECT_EQ(FiveSeven.truncate(2), ConstantRange(APInt(2, 1), APInt(2, 3)));
463 
464   // trunc([7, 1), 3->2) = [3, 1)
465   ConstantRange SevenOne(APInt(3, 7), APInt(3, 1));
466   EXPECT_EQ(SevenOne.truncate(2), ConstantRange(APInt(2, 3), APInt(2, 1)));
467 }
468 
469 TEST_F(ConstantRangeTest, ZExt) {
470   ConstantRange ZFull = Full.zeroExtend(20);
471   ConstantRange ZEmpty = Empty.zeroExtend(20);
472   ConstantRange ZOne = One.zeroExtend(20);
473   ConstantRange ZSome = Some.zeroExtend(20);
474   ConstantRange ZWrap = Wrap.zeroExtend(20);
475   EXPECT_EQ(ZFull, ConstantRange(APInt(20, 0), APInt(20, 0x10000)));
476   EXPECT_TRUE(ZEmpty.isEmptySet());
477   EXPECT_EQ(ZOne, ConstantRange(One.getLower().zext(20),
478                                 One.getUpper().zext(20)));
479   EXPECT_EQ(ZSome, ConstantRange(Some.getLower().zext(20),
480                                  Some.getUpper().zext(20)));
481   EXPECT_EQ(ZWrap, ConstantRange(APInt(20, 0), APInt(20, 0x10000)));
482 
483   // zext([5, 0), 3->7) = [5, 8)
484   ConstantRange FiveZero(APInt(3, 5), APInt(3, 0));
485   EXPECT_EQ(FiveZero.zeroExtend(7), ConstantRange(APInt(7, 5), APInt(7, 8)));
486 }
487 
488 TEST_F(ConstantRangeTest, SExt) {
489   ConstantRange SFull = Full.signExtend(20);
490   ConstantRange SEmpty = Empty.signExtend(20);
491   ConstantRange SOne = One.signExtend(20);
492   ConstantRange SSome = Some.signExtend(20);
493   ConstantRange SWrap = Wrap.signExtend(20);
494   EXPECT_EQ(SFull, ConstantRange(APInt(20, (uint64_t)INT16_MIN, true),
495                                  APInt(20, INT16_MAX + 1, true)));
496   EXPECT_TRUE(SEmpty.isEmptySet());
497   EXPECT_EQ(SOne, ConstantRange(One.getLower().sext(20),
498                                 One.getUpper().sext(20)));
499   EXPECT_EQ(SSome, ConstantRange(Some.getLower().sext(20),
500                                  Some.getUpper().sext(20)));
501   EXPECT_EQ(SWrap, ConstantRange(APInt(20, (uint64_t)INT16_MIN, true),
502                                  APInt(20, INT16_MAX + 1, true)));
503 
504   EXPECT_EQ(ConstantRange(APInt(8, 120), APInt(8, 140)).signExtend(16),
505             ConstantRange(APInt(16, -128), APInt(16, 128)));
506 
507   EXPECT_EQ(ConstantRange(APInt(16, 0x0200), APInt(16, 0x8000)).signExtend(19),
508             ConstantRange(APInt(19, 0x0200), APInt(19, 0x8000)));
509 }
510 
511 TEST_F(ConstantRangeTest, IntersectWith) {
512   EXPECT_EQ(Empty.intersectWith(Full), Empty);
513   EXPECT_EQ(Empty.intersectWith(Empty), Empty);
514   EXPECT_EQ(Empty.intersectWith(One), Empty);
515   EXPECT_EQ(Empty.intersectWith(Some), Empty);
516   EXPECT_EQ(Empty.intersectWith(Wrap), Empty);
517   EXPECT_EQ(Full.intersectWith(Full), Full);
518   EXPECT_EQ(Some.intersectWith(Some), Some);
519   EXPECT_EQ(Some.intersectWith(One), One);
520   EXPECT_EQ(Full.intersectWith(One), One);
521   EXPECT_EQ(Full.intersectWith(Some), Some);
522   EXPECT_EQ(Some.intersectWith(Wrap), Empty);
523   EXPECT_EQ(One.intersectWith(Wrap), Empty);
524   EXPECT_EQ(One.intersectWith(Wrap), Wrap.intersectWith(One));
525 
526   // Klee generated testcase from PR4545.
527   // The intersection of i16 [4, 2) and [6, 5) is disjoint, looking like
528   // 01..4.6789ABCDEF where the dots represent values not in the intersection.
529   ConstantRange LHS(APInt(16, 4), APInt(16, 2));
530   ConstantRange RHS(APInt(16, 6), APInt(16, 5));
531   EXPECT_TRUE(LHS.intersectWith(RHS) == LHS);
532 
533   // previous bug: intersection of [min, 3) and [2, max) should be 2
534   LHS = ConstantRange(APInt(32, -2147483646), APInt(32, 3));
535   RHS = ConstantRange(APInt(32, 2), APInt(32, 2147483646));
536   EXPECT_EQ(LHS.intersectWith(RHS), ConstantRange(APInt(32, 2)));
537 
538   // [2, 0) /\ [4, 3) = [2, 0)
539   LHS = ConstantRange(APInt(32, 2), APInt(32, 0));
540   RHS = ConstantRange(APInt(32, 4), APInt(32, 3));
541   EXPECT_EQ(LHS.intersectWith(RHS), ConstantRange(APInt(32, 2), APInt(32, 0)));
542 
543   // [2, 0) /\ [4, 2) = [4, 0)
544   LHS = ConstantRange(APInt(32, 2), APInt(32, 0));
545   RHS = ConstantRange(APInt(32, 4), APInt(32, 2));
546   EXPECT_EQ(LHS.intersectWith(RHS), ConstantRange(APInt(32, 4), APInt(32, 0)));
547 
548   // [4, 2) /\ [5, 1) = [5, 1)
549   LHS = ConstantRange(APInt(32, 4), APInt(32, 2));
550   RHS = ConstantRange(APInt(32, 5), APInt(32, 1));
551   EXPECT_EQ(LHS.intersectWith(RHS), ConstantRange(APInt(32, 5), APInt(32, 1)));
552 
553   // [2, 0) /\ [7, 4) = [7, 4)
554   LHS = ConstantRange(APInt(32, 2), APInt(32, 0));
555   RHS = ConstantRange(APInt(32, 7), APInt(32, 4));
556   EXPECT_EQ(LHS.intersectWith(RHS), ConstantRange(APInt(32, 7), APInt(32, 4)));
557 
558   // [4, 2) /\ [1, 0) = [1, 0)
559   LHS = ConstantRange(APInt(32, 4), APInt(32, 2));
560   RHS = ConstantRange(APInt(32, 1), APInt(32, 0));
561   EXPECT_EQ(LHS.intersectWith(RHS), ConstantRange(APInt(32, 4), APInt(32, 2)));
562 
563   // [15, 0) /\ [7, 6) = [15, 0)
564   LHS = ConstantRange(APInt(32, 15), APInt(32, 0));
565   RHS = ConstantRange(APInt(32, 7), APInt(32, 6));
566   EXPECT_EQ(LHS.intersectWith(RHS), ConstantRange(APInt(32, 15), APInt(32, 0)));
567 }
568 
569 template<typename Fn1, typename Fn2, typename Fn3>
570 void testBinarySetOperationExhaustive(Fn1 OpFn, Fn2 ExactOpFn, Fn3 InResultFn) {
571   unsigned Bits = 4;
572   EnumerateTwoConstantRanges(Bits,
573       [=](const ConstantRange &CR1, const ConstantRange &CR2) {
574         SmallBitVector Elems(1 << Bits);
575         APInt Num(Bits, 0);
576         for (unsigned I = 0, Limit = 1 << Bits; I < Limit; ++I, ++Num)
577           if (InResultFn(CR1, CR2, Num))
578             Elems.set(Num.getZExtValue());
579 
580         ConstantRange SmallestCR = OpFn(CR1, CR2, ConstantRange::Smallest);
581         TestRange(SmallestCR, Elems, PreferSmallest, {CR1, CR2});
582 
583         ConstantRange UnsignedCR = OpFn(CR1, CR2, ConstantRange::Unsigned);
584         TestRange(UnsignedCR, Elems, PreferSmallestNonFullUnsigned, {CR1, CR2});
585 
586         ConstantRange SignedCR = OpFn(CR1, CR2, ConstantRange::Signed);
587         TestRange(SignedCR, Elems, PreferSmallestNonFullSigned, {CR1, CR2});
588 
589         Optional<ConstantRange> ExactCR = ExactOpFn(CR1, CR2);
590         if (SmallestCR.isSizeLargerThan(Elems.count())) {
591           EXPECT_TRUE(!ExactCR.hasValue());
592         } else {
593           EXPECT_EQ(SmallestCR, *ExactCR);
594         }
595       });
596 }
597 
598 TEST_F(ConstantRangeTest, IntersectWithExhaustive) {
599   testBinarySetOperationExhaustive(
600       [](const ConstantRange &CR1, const ConstantRange &CR2,
601          ConstantRange::PreferredRangeType Type) {
602         return CR1.intersectWith(CR2, Type);
603       },
604       [](const ConstantRange &CR1, const ConstantRange &CR2) {
605         return CR1.exactIntersectWith(CR2);
606       },
607       [](const ConstantRange &CR1, const ConstantRange &CR2, const APInt &N) {
608         return CR1.contains(N) && CR2.contains(N);
609       });
610 }
611 
612 TEST_F(ConstantRangeTest, UnionWithExhaustive) {
613   testBinarySetOperationExhaustive(
614       [](const ConstantRange &CR1, const ConstantRange &CR2,
615          ConstantRange::PreferredRangeType Type) {
616         return CR1.unionWith(CR2, Type);
617       },
618       [](const ConstantRange &CR1, const ConstantRange &CR2) {
619         return CR1.exactUnionWith(CR2);
620       },
621       [](const ConstantRange &CR1, const ConstantRange &CR2, const APInt &N) {
622         return CR1.contains(N) || CR2.contains(N);
623       });
624 }
625 
626 TEST_F(ConstantRangeTest, UnionWith) {
627   EXPECT_EQ(Wrap.unionWith(One),
628             ConstantRange(APInt(16, 0xaaa), APInt(16, 0xb)));
629   EXPECT_EQ(One.unionWith(Wrap), Wrap.unionWith(One));
630   EXPECT_EQ(Empty.unionWith(Empty), Empty);
631   EXPECT_EQ(Full.unionWith(Full), Full);
632   EXPECT_EQ(Some.unionWith(Wrap), Full);
633 
634   // PR4545
635   EXPECT_EQ(ConstantRange(APInt(16, 14), APInt(16, 1)).unionWith(
636                                     ConstantRange(APInt(16, 0), APInt(16, 8))),
637             ConstantRange(APInt(16, 14), APInt(16, 8)));
638   EXPECT_EQ(ConstantRange(APInt(16, 6), APInt(16, 4)).unionWith(
639                                     ConstantRange(APInt(16, 4), APInt(16, 0))),
640             ConstantRange::getFull(16));
641   EXPECT_EQ(ConstantRange(APInt(16, 1), APInt(16, 0)).unionWith(
642                                     ConstantRange(APInt(16, 2), APInt(16, 1))),
643             ConstantRange::getFull(16));
644 }
645 
646 TEST_F(ConstantRangeTest, SetDifference) {
647   EXPECT_EQ(Full.difference(Empty), Full);
648   EXPECT_EQ(Full.difference(Full), Empty);
649   EXPECT_EQ(Empty.difference(Empty), Empty);
650   EXPECT_EQ(Empty.difference(Full), Empty);
651 
652   ConstantRange A(APInt(16, 3), APInt(16, 7));
653   ConstantRange B(APInt(16, 5), APInt(16, 9));
654   ConstantRange C(APInt(16, 3), APInt(16, 5));
655   ConstantRange D(APInt(16, 7), APInt(16, 9));
656   ConstantRange E(APInt(16, 5), APInt(16, 4));
657   ConstantRange F(APInt(16, 7), APInt(16, 3));
658   EXPECT_EQ(A.difference(B), C);
659   EXPECT_EQ(B.difference(A), D);
660   EXPECT_EQ(E.difference(A), F);
661 }
662 
663 TEST_F(ConstantRangeTest, getActiveBits) {
664   unsigned Bits = 4;
665   EnumerateConstantRanges(Bits, [&](const ConstantRange &CR) {
666     unsigned Exact = 0;
667     ForeachNumInConstantRange(CR, [&](const APInt &N) {
668       Exact = std::max(Exact, N.getActiveBits());
669     });
670 
671     unsigned ResultCR = CR.getActiveBits();
672     EXPECT_EQ(Exact, ResultCR);
673   });
674 }
675 TEST_F(ConstantRangeTest, losslessUnsignedTruncationZeroext) {
676   unsigned Bits = 4;
677   EnumerateConstantRanges(Bits, [&](const ConstantRange &CR) {
678     unsigned MinBitWidth = CR.getActiveBits();
679     if (MinBitWidth == 0) {
680       EXPECT_TRUE(CR.isEmptySet() ||
681                   (CR.isSingleElement() && CR.getSingleElement()->isZero()));
682       return;
683     }
684     if (MinBitWidth == Bits)
685       return;
686     EXPECT_EQ(CR, CR.truncate(MinBitWidth).zeroExtend(Bits));
687   });
688 }
689 
690 TEST_F(ConstantRangeTest, getMinSignedBits) {
691   unsigned Bits = 4;
692   EnumerateConstantRanges(Bits, [&](const ConstantRange &CR) {
693     unsigned Exact = 0;
694     ForeachNumInConstantRange(CR, [&](const APInt &N) {
695       Exact = std::max(Exact, N.getMinSignedBits());
696     });
697 
698     unsigned ResultCR = CR.getMinSignedBits();
699     EXPECT_EQ(Exact, ResultCR);
700   });
701 }
702 TEST_F(ConstantRangeTest, losslessSignedTruncationSignext) {
703   unsigned Bits = 4;
704   EnumerateConstantRanges(Bits, [&](const ConstantRange &CR) {
705     unsigned MinBitWidth = CR.getMinSignedBits();
706     if (MinBitWidth == 0) {
707       EXPECT_TRUE(CR.isEmptySet());
708       return;
709     }
710     if (MinBitWidth == Bits)
711       return;
712     EXPECT_EQ(CR, CR.truncate(MinBitWidth).signExtend(Bits));
713   });
714 }
715 
716 TEST_F(ConstantRangeTest, SubtractAPInt) {
717   EXPECT_EQ(Full.subtract(APInt(16, 4)), Full);
718   EXPECT_EQ(Empty.subtract(APInt(16, 4)), Empty);
719   EXPECT_EQ(Some.subtract(APInt(16, 4)),
720             ConstantRange(APInt(16, 0x6), APInt(16, 0xaa6)));
721   EXPECT_EQ(Wrap.subtract(APInt(16, 4)),
722             ConstantRange(APInt(16, 0xaa6), APInt(16, 0x6)));
723   EXPECT_EQ(One.subtract(APInt(16, 4)),
724             ConstantRange(APInt(16, 0x6)));
725 }
726 
727 TEST_F(ConstantRangeTest, Add) {
728   EXPECT_EQ(Full.add(APInt(16, 4)), Full);
729   EXPECT_EQ(Full.add(Full), Full);
730   EXPECT_EQ(Full.add(Empty), Empty);
731   EXPECT_EQ(Full.add(One), Full);
732   EXPECT_EQ(Full.add(Some), Full);
733   EXPECT_EQ(Full.add(Wrap), Full);
734   EXPECT_EQ(Empty.add(Empty), Empty);
735   EXPECT_EQ(Empty.add(One), Empty);
736   EXPECT_EQ(Empty.add(Some), Empty);
737   EXPECT_EQ(Empty.add(Wrap), Empty);
738   EXPECT_EQ(Empty.add(APInt(16, 4)), Empty);
739   EXPECT_EQ(Some.add(APInt(16, 4)),
740             ConstantRange(APInt(16, 0xe), APInt(16, 0xaae)));
741   EXPECT_EQ(Wrap.add(APInt(16, 4)),
742             ConstantRange(APInt(16, 0xaae), APInt(16, 0xe)));
743   EXPECT_EQ(One.add(APInt(16, 4)),
744             ConstantRange(APInt(16, 0xe)));
745 
746   TestBinaryOpExhaustive(
747       [](const ConstantRange &CR1, const ConstantRange &CR2) {
748         return CR1.add(CR2);
749       },
750       [](const APInt &N1, const APInt &N2) {
751         return N1 + N2;
752       });
753 }
754 
755 template <typename Fn1, typename Fn2>
756 static void TestAddWithNoSignedWrapExhaustive(Fn1 RangeFn, Fn2 IntFn) {
757   unsigned Bits = 4;
758   EnumerateTwoConstantRanges(Bits, [&](const ConstantRange &CR1,
759                                        const ConstantRange &CR2) {
760     ConstantRange CR = RangeFn(CR1, CR2);
761     SignedOpRangeGatherer R(CR.getBitWidth());
762     bool AllOverflow = true;
763     ForeachNumInConstantRange(CR1, [&](const APInt &N1) {
764       ForeachNumInConstantRange(CR2, [&](const APInt &N2) {
765         bool IsOverflow = false;
766         APInt N = IntFn(IsOverflow, N1, N2);
767         if (!IsOverflow) {
768           AllOverflow = false;
769           R.account(N);
770           EXPECT_TRUE(CR.contains(N));
771         }
772       });
773     });
774 
775     EXPECT_EQ(CR.isEmptySet(), AllOverflow);
776 
777     if (CR1.isSignWrappedSet() || CR2.isSignWrappedSet())
778       return;
779 
780     ConstantRange Exact = R.getRange();
781     EXPECT_EQ(Exact, CR);
782   });
783 }
784 
785 template <typename Fn1, typename Fn2>
786 static void TestAddWithNoUnsignedWrapExhaustive(Fn1 RangeFn, Fn2 IntFn) {
787   unsigned Bits = 4;
788   EnumerateTwoConstantRanges(Bits, [&](const ConstantRange &CR1,
789                                        const ConstantRange &CR2) {
790     ConstantRange CR = RangeFn(CR1, CR2);
791     UnsignedOpRangeGatherer R(CR.getBitWidth());
792     bool AllOverflow = true;
793     ForeachNumInConstantRange(CR1, [&](const APInt &N1) {
794       ForeachNumInConstantRange(CR2, [&](const APInt &N2) {
795         bool IsOverflow = false;
796         APInt N = IntFn(IsOverflow, N1, N2);
797         if (!IsOverflow) {
798           AllOverflow = false;
799           R.account(N);
800           EXPECT_TRUE(CR.contains(N));
801         }
802       });
803     });
804 
805     EXPECT_EQ(CR.isEmptySet(), AllOverflow);
806 
807     if (CR1.isWrappedSet() || CR2.isWrappedSet())
808       return;
809 
810     ConstantRange Exact = R.getRange();
811     EXPECT_EQ(Exact, CR);
812   });
813 }
814 
815 template <typename Fn1, typename Fn2, typename Fn3>
816 static void TestAddWithNoSignedUnsignedWrapExhaustive(Fn1 RangeFn,
817                                                       Fn2 IntFnSigned,
818                                                       Fn3 IntFnUnsigned) {
819   unsigned Bits = 4;
820   EnumerateTwoConstantRanges(
821       Bits, [&](const ConstantRange &CR1, const ConstantRange &CR2) {
822         ConstantRange CR = RangeFn(CR1, CR2);
823         UnsignedOpRangeGatherer UR(CR.getBitWidth());
824         SignedOpRangeGatherer SR(CR.getBitWidth());
825         bool AllOverflow = true;
826         ForeachNumInConstantRange(CR1, [&](const APInt &N1) {
827           ForeachNumInConstantRange(CR2, [&](const APInt &N2) {
828             bool IsOverflow = false, IsSignedOverflow = false;
829             APInt N = IntFnSigned(IsSignedOverflow, N1, N2);
830             (void) IntFnUnsigned(IsOverflow, N1, N2);
831             if (!IsSignedOverflow && !IsOverflow) {
832               AllOverflow = false;
833               UR.account(N);
834               SR.account(N);
835               EXPECT_TRUE(CR.contains(N));
836             }
837           });
838         });
839 
840         EXPECT_EQ(CR.isEmptySet(), AllOverflow);
841 
842         if (CR1.isWrappedSet() || CR2.isWrappedSet() ||
843             CR1.isSignWrappedSet() || CR2.isSignWrappedSet())
844           return;
845 
846         ConstantRange ExactUnsignedCR = UR.getRange();
847         ConstantRange ExactSignedCR = SR.getRange();
848 
849         if (ExactUnsignedCR.isEmptySet() || ExactSignedCR.isEmptySet()) {
850           EXPECT_TRUE(CR.isEmptySet());
851           return;
852         }
853 
854         ConstantRange Exact = ExactSignedCR.intersectWith(ExactUnsignedCR);
855         EXPECT_EQ(Exact, CR);
856       });
857 }
858 
859 TEST_F(ConstantRangeTest, AddWithNoWrap) {
860   typedef OverflowingBinaryOperator OBO;
861   EXPECT_EQ(Empty.addWithNoWrap(Some, OBO::NoSignedWrap), Empty);
862   EXPECT_EQ(Some.addWithNoWrap(Empty, OBO::NoSignedWrap), Empty);
863   EXPECT_EQ(Full.addWithNoWrap(Full, OBO::NoSignedWrap), Full);
864   EXPECT_NE(Full.addWithNoWrap(Some, OBO::NoSignedWrap), Full);
865   EXPECT_NE(Some.addWithNoWrap(Full, OBO::NoSignedWrap), Full);
866   EXPECT_EQ(Full.addWithNoWrap(ConstantRange(APInt(16, 1), APInt(16, 2)),
867                                OBO::NoSignedWrap),
868             ConstantRange(APInt(16, INT16_MIN + 1), APInt(16, INT16_MIN)));
869   EXPECT_EQ(ConstantRange(APInt(16, 1), APInt(16, 2))
870                 .addWithNoWrap(Full, OBO::NoSignedWrap),
871             ConstantRange(APInt(16, INT16_MIN + 1), APInt(16, INT16_MIN)));
872   EXPECT_EQ(Full.addWithNoWrap(ConstantRange(APInt(16, -1), APInt(16, 0)),
873                                OBO::NoSignedWrap),
874             ConstantRange(APInt(16, INT16_MIN), APInt(16, INT16_MAX)));
875   EXPECT_EQ(ConstantRange(APInt(8, 100), APInt(8, 120))
876                 .addWithNoWrap(ConstantRange(APInt(8, 120), APInt(8, 123)),
877                                OBO::NoSignedWrap),
878             ConstantRange(8, false));
879   EXPECT_EQ(ConstantRange(APInt(8, -120), APInt(8, -100))
880                 .addWithNoWrap(ConstantRange(APInt(8, -110), APInt(8, -100)),
881                                OBO::NoSignedWrap),
882             ConstantRange(8, false));
883   EXPECT_EQ(ConstantRange(APInt(8, 0), APInt(8, 101))
884                 .addWithNoWrap(ConstantRange(APInt(8, -128), APInt(8, 28)),
885                                OBO::NoSignedWrap),
886             ConstantRange(8, true));
887   EXPECT_EQ(ConstantRange(APInt(8, 0), APInt(8, 101))
888                 .addWithNoWrap(ConstantRange(APInt(8, -120), APInt(8, 29)),
889                                OBO::NoSignedWrap),
890             ConstantRange(APInt(8, -120), APInt(8, -128)));
891   EXPECT_EQ(ConstantRange(APInt(8, -50), APInt(8, 50))
892                 .addWithNoWrap(ConstantRange(APInt(8, 10), APInt(8, 20)),
893                                OBO::NoSignedWrap),
894             ConstantRange(APInt(8, -40), APInt(8, 69)));
895   EXPECT_EQ(ConstantRange(APInt(8, 10), APInt(8, 20))
896                 .addWithNoWrap(ConstantRange(APInt(8, -50), APInt(8, 50)),
897                                OBO::NoSignedWrap),
898             ConstantRange(APInt(8, -40), APInt(8, 69)));
899   EXPECT_EQ(ConstantRange(APInt(8, 120), APInt(8, -10))
900                 .addWithNoWrap(ConstantRange(APInt(8, 5), APInt(8, 20)),
901                                OBO::NoSignedWrap),
902             ConstantRange(APInt(8, 125), APInt(8, 9)));
903   EXPECT_EQ(ConstantRange(APInt(8, 5), APInt(8, 20))
904                 .addWithNoWrap(ConstantRange(APInt(8, 120), APInt(8, -10)),
905                                OBO::NoSignedWrap),
906             ConstantRange(APInt(8, 125), APInt(8, 9)));
907 
908   TestAddWithNoSignedWrapExhaustive(
909       [](const ConstantRange &CR1, const ConstantRange &CR2) {
910         return CR1.addWithNoWrap(CR2, OBO::NoSignedWrap);
911       },
912       [](bool &IsOverflow, const APInt &N1, const APInt &N2) {
913         return N1.sadd_ov(N2, IsOverflow);
914       });
915 
916   EXPECT_EQ(Empty.addWithNoWrap(Some, OBO::NoUnsignedWrap), Empty);
917   EXPECT_EQ(Some.addWithNoWrap(Empty, OBO::NoUnsignedWrap), Empty);
918   EXPECT_EQ(Full.addWithNoWrap(Full, OBO::NoUnsignedWrap), Full);
919   EXPECT_NE(Full.addWithNoWrap(Some, OBO::NoUnsignedWrap), Full);
920   EXPECT_NE(Some.addWithNoWrap(Full, OBO::NoUnsignedWrap), Full);
921   EXPECT_EQ(Full.addWithNoWrap(ConstantRange(APInt(16, 1), APInt(16, 2)),
922                                OBO::NoUnsignedWrap),
923             ConstantRange(APInt(16, 1), APInt(16, 0)));
924   EXPECT_EQ(ConstantRange(APInt(16, 1), APInt(16, 2))
925                 .addWithNoWrap(Full, OBO::NoUnsignedWrap),
926             ConstantRange(APInt(16, 1), APInt(16, 0)));
927   EXPECT_EQ(ConstantRange(APInt(8, 200), APInt(8, 220))
928                 .addWithNoWrap(ConstantRange(APInt(8, 100), APInt(8, 123)),
929                                OBO::NoUnsignedWrap),
930             ConstantRange(8, false));
931   EXPECT_EQ(ConstantRange(APInt(8, 0), APInt(8, 101))
932                 .addWithNoWrap(ConstantRange(APInt(8, 0), APInt(8, 156)),
933                                OBO::NoUnsignedWrap),
934             ConstantRange(8, true));
935   EXPECT_EQ(ConstantRange(APInt(8, 0), APInt(8, 101))
936                 .addWithNoWrap(ConstantRange(APInt(8, 10), APInt(8, 29)),
937                                OBO::NoUnsignedWrap),
938             ConstantRange(APInt(8, 10), APInt(8, 129)));
939   EXPECT_EQ(ConstantRange(APInt(8, 20), APInt(8, 10))
940                 .addWithNoWrap(ConstantRange(APInt(8, 50), APInt(8, 200)),
941                                OBO::NoUnsignedWrap),
942             ConstantRange(APInt(8, 50), APInt(8, 0)));
943   EXPECT_EQ(ConstantRange(APInt(8, 10), APInt(8, 20))
944                 .addWithNoWrap(ConstantRange(APInt(8, 50), APInt(8, 200)),
945                                OBO::NoUnsignedWrap),
946             ConstantRange(APInt(8, 60), APInt(8, -37)));
947   EXPECT_EQ(ConstantRange(APInt(8, 20), APInt(8, -30))
948                 .addWithNoWrap(ConstantRange(APInt(8, 5), APInt(8, 20)),
949                                OBO::NoUnsignedWrap),
950             ConstantRange(APInt(8, 25), APInt(8, -11)));
951   EXPECT_EQ(ConstantRange(APInt(8, 5), APInt(8, 20))
952                 .addWithNoWrap(ConstantRange(APInt(8, 20), APInt(8, -30)),
953                                OBO::NoUnsignedWrap),
954             ConstantRange(APInt(8, 25), APInt(8, -11)));
955 
956   TestAddWithNoUnsignedWrapExhaustive(
957       [](const ConstantRange &CR1, const ConstantRange &CR2) {
958         return CR1.addWithNoWrap(CR2, OBO::NoUnsignedWrap);
959       },
960       [](bool &IsOverflow, const APInt &N1, const APInt &N2) {
961         return N1.uadd_ov(N2, IsOverflow);
962       });
963 
964   EXPECT_EQ(ConstantRange(APInt(8, 50), APInt(8, 100))
965                 .addWithNoWrap(ConstantRange(APInt(8, 20), APInt(8, 70)),
966                                OBO::NoSignedWrap),
967             ConstantRange(APInt(8, 70), APInt(8, -128)));
968   EXPECT_EQ(ConstantRange(APInt(8, 50), APInt(8, 100))
969                 .addWithNoWrap(ConstantRange(APInt(8, 20), APInt(8, 70)),
970                                OBO::NoUnsignedWrap),
971             ConstantRange(APInt(8, 70), APInt(8, 169)));
972   EXPECT_EQ(ConstantRange(APInt(8, 50), APInt(8, 100))
973                 .addWithNoWrap(ConstantRange(APInt(8, 20), APInt(8, 70)),
974                                OBO::NoUnsignedWrap | OBO::NoSignedWrap),
975             ConstantRange(APInt(8, 70), APInt(8, -128)));
976 
977   EXPECT_EQ(ConstantRange(APInt(8, -100), APInt(8, -50))
978                 .addWithNoWrap(ConstantRange(APInt(8, 20), APInt(8, 30)),
979                                OBO::NoSignedWrap),
980             ConstantRange(APInt(8, -80), APInt(8, -21)));
981   EXPECT_EQ(ConstantRange(APInt(8, -100), APInt(8, -50))
982                 .addWithNoWrap(ConstantRange(APInt(8, 20), APInt(8, 30)),
983                                OBO::NoUnsignedWrap),
984             ConstantRange(APInt(8, 176), APInt(8, 235)));
985   EXPECT_EQ(ConstantRange(APInt(8, -100), APInt(8, -50))
986                 .addWithNoWrap(ConstantRange(APInt(8, 20), APInt(8, 30)),
987                                OBO::NoUnsignedWrap | OBO::NoSignedWrap),
988             ConstantRange(APInt(8, 176), APInt(8, 235)));
989 
990   TestAddWithNoSignedUnsignedWrapExhaustive(
991       [](const ConstantRange &CR1, const ConstantRange &CR2) {
992         return CR1.addWithNoWrap(CR2, OBO::NoUnsignedWrap | OBO::NoSignedWrap);
993       },
994       [](bool &IsOverflow, const APInt &N1, const APInt &N2) {
995         return N1.sadd_ov(N2, IsOverflow);
996       },
997       [](bool &IsOverflow, const APInt &N1, const APInt &N2) {
998         return N1.uadd_ov(N2, IsOverflow);
999       });
1000 }
1001 
1002 TEST_F(ConstantRangeTest, Sub) {
1003   EXPECT_EQ(Full.sub(APInt(16, 4)), Full);
1004   EXPECT_EQ(Full.sub(Full), Full);
1005   EXPECT_EQ(Full.sub(Empty), Empty);
1006   EXPECT_EQ(Full.sub(One), Full);
1007   EXPECT_EQ(Full.sub(Some), Full);
1008   EXPECT_EQ(Full.sub(Wrap), Full);
1009   EXPECT_EQ(Empty.sub(Empty), Empty);
1010   EXPECT_EQ(Empty.sub(One), Empty);
1011   EXPECT_EQ(Empty.sub(Some), Empty);
1012   EXPECT_EQ(Empty.sub(Wrap), Empty);
1013   EXPECT_EQ(Empty.sub(APInt(16, 4)), Empty);
1014   EXPECT_EQ(Some.sub(APInt(16, 4)),
1015             ConstantRange(APInt(16, 0x6), APInt(16, 0xaa6)));
1016   EXPECT_EQ(Some.sub(Some),
1017             ConstantRange(APInt(16, 0xf561), APInt(16, 0xaa0)));
1018   EXPECT_EQ(Wrap.sub(APInt(16, 4)),
1019             ConstantRange(APInt(16, 0xaa6), APInt(16, 0x6)));
1020   EXPECT_EQ(One.sub(APInt(16, 4)),
1021             ConstantRange(APInt(16, 0x6)));
1022 
1023   TestBinaryOpExhaustive(
1024       [](const ConstantRange &CR1, const ConstantRange &CR2) {
1025         return CR1.sub(CR2);
1026       },
1027       [](const APInt &N1, const APInt &N2) {
1028         return N1 - N2;
1029       });
1030 }
1031 
1032 TEST_F(ConstantRangeTest, SubWithNoWrap) {
1033   typedef OverflowingBinaryOperator OBO;
1034   TestAddWithNoSignedWrapExhaustive(
1035       [](const ConstantRange &CR1, const ConstantRange &CR2) {
1036         return CR1.subWithNoWrap(CR2, OBO::NoSignedWrap);
1037       },
1038       [](bool &IsOverflow, const APInt &N1, const APInt &N2) {
1039         return N1.ssub_ov(N2, IsOverflow);
1040       });
1041   TestAddWithNoUnsignedWrapExhaustive(
1042       [](const ConstantRange &CR1, const ConstantRange &CR2) {
1043         return CR1.subWithNoWrap(CR2, OBO::NoUnsignedWrap);
1044       },
1045       [](bool &IsOverflow, const APInt &N1, const APInt &N2) {
1046         return N1.usub_ov(N2, IsOverflow);
1047       });
1048   TestAddWithNoSignedUnsignedWrapExhaustive(
1049       [](const ConstantRange &CR1, const ConstantRange &CR2) {
1050         return CR1.subWithNoWrap(CR2, OBO::NoUnsignedWrap | OBO::NoSignedWrap);
1051       },
1052       [](bool &IsOverflow, const APInt &N1, const APInt &N2) {
1053         return N1.ssub_ov(N2, IsOverflow);
1054       },
1055       [](bool &IsOverflow, const APInt &N1, const APInt &N2) {
1056         return N1.usub_ov(N2, IsOverflow);
1057       });
1058 }
1059 
1060 TEST_F(ConstantRangeTest, Multiply) {
1061   EXPECT_EQ(Full.multiply(Full), Full);
1062   EXPECT_EQ(Full.multiply(Empty), Empty);
1063   EXPECT_EQ(Full.multiply(One), Full);
1064   EXPECT_EQ(Full.multiply(Some), Full);
1065   EXPECT_EQ(Full.multiply(Wrap), Full);
1066   EXPECT_EQ(Empty.multiply(Empty), Empty);
1067   EXPECT_EQ(Empty.multiply(One), Empty);
1068   EXPECT_EQ(Empty.multiply(Some), Empty);
1069   EXPECT_EQ(Empty.multiply(Wrap), Empty);
1070   EXPECT_EQ(One.multiply(One), ConstantRange(APInt(16, 0xa*0xa),
1071                                              APInt(16, 0xa*0xa + 1)));
1072   EXPECT_EQ(One.multiply(Some), ConstantRange(APInt(16, 0xa*0xa),
1073                                               APInt(16, 0xa*0xaa9 + 1)));
1074   EXPECT_EQ(One.multiply(Wrap), Full);
1075   EXPECT_EQ(Some.multiply(Some), Full);
1076   EXPECT_EQ(Some.multiply(Wrap), Full);
1077   EXPECT_EQ(Wrap.multiply(Wrap), Full);
1078 
1079   ConstantRange Zero(APInt(16, 0));
1080   EXPECT_EQ(Zero.multiply(Full), Zero);
1081   EXPECT_EQ(Zero.multiply(Some), Zero);
1082   EXPECT_EQ(Zero.multiply(Wrap), Zero);
1083   EXPECT_EQ(Full.multiply(Zero), Zero);
1084   EXPECT_EQ(Some.multiply(Zero), Zero);
1085   EXPECT_EQ(Wrap.multiply(Zero), Zero);
1086 
1087   // http://llvm.org/PR4545
1088   EXPECT_EQ(ConstantRange(APInt(4, 1), APInt(4, 6)).multiply(
1089                 ConstantRange(APInt(4, 6), APInt(4, 2))),
1090             ConstantRange(4, /*isFullSet=*/true));
1091 
1092   EXPECT_EQ(ConstantRange(APInt(8, 254), APInt(8, 0)).multiply(
1093               ConstantRange(APInt(8, 252), APInt(8, 4))),
1094             ConstantRange(APInt(8, 250), APInt(8, 9)));
1095   EXPECT_EQ(ConstantRange(APInt(8, 254), APInt(8, 255)).multiply(
1096               ConstantRange(APInt(8, 2), APInt(8, 4))),
1097             ConstantRange(APInt(8, 250), APInt(8, 253)));
1098 
1099   // TODO: This should be return [-2, 0]
1100   EXPECT_EQ(ConstantRange(APInt(8, -2)).multiply(
1101               ConstantRange(APInt(8, 0), APInt(8, 2))),
1102             ConstantRange(APInt(8, -2), APInt(8, 1)));
1103 }
1104 
1105 TEST_F(ConstantRangeTest, smul_fast) {
1106   TestBinaryOpExhaustive(
1107       [](const ConstantRange &CR1, const ConstantRange &CR2) {
1108         return CR1.smul_fast(CR2);
1109       },
1110       [](const APInt &N1, const APInt &N2) {
1111         return N1 * N2;
1112       },
1113       PreferSmallest,
1114       [](const ConstantRange &, const ConstantRange &) {
1115         return false; // Check correctness only.
1116       });
1117 }
1118 
1119 TEST_F(ConstantRangeTest, UMax) {
1120   EXPECT_EQ(Full.umax(Full), Full);
1121   EXPECT_EQ(Full.umax(Empty), Empty);
1122   EXPECT_EQ(Full.umax(Some), ConstantRange(APInt(16, 0xa), APInt(16, 0)));
1123   EXPECT_EQ(Full.umax(Wrap), Full);
1124   EXPECT_EQ(Full.umax(Some), ConstantRange(APInt(16, 0xa), APInt(16, 0)));
1125   EXPECT_EQ(Empty.umax(Empty), Empty);
1126   EXPECT_EQ(Empty.umax(Some), Empty);
1127   EXPECT_EQ(Empty.umax(Wrap), Empty);
1128   EXPECT_EQ(Empty.umax(One), Empty);
1129   EXPECT_EQ(Some.umax(Some), Some);
1130   EXPECT_EQ(Some.umax(Wrap), ConstantRange(APInt(16, 0xa), APInt(16, 0)));
1131   EXPECT_EQ(Some.umax(One), Some);
1132   EXPECT_EQ(Wrap.umax(Wrap), Wrap);
1133   EXPECT_EQ(Wrap.umax(One), ConstantRange(APInt(16, 0xa), APInt(16, 0)));
1134   EXPECT_EQ(One.umax(One), One);
1135 
1136   TestBinaryOpExhaustive(
1137       [](const ConstantRange &CR1, const ConstantRange &CR2) {
1138         return CR1.umax(CR2);
1139       },
1140       [](const APInt &N1, const APInt &N2) {
1141         return APIntOps::umax(N1, N2);
1142       },
1143       PreferSmallestNonFullUnsigned);
1144 }
1145 
1146 TEST_F(ConstantRangeTest, SMax) {
1147   EXPECT_EQ(Full.smax(Full), Full);
1148   EXPECT_EQ(Full.smax(Empty), Empty);
1149   EXPECT_EQ(Full.smax(Some), ConstantRange(APInt(16, 0xa),
1150                                            APInt::getSignedMinValue(16)));
1151   EXPECT_EQ(Full.smax(Wrap), Full);
1152   EXPECT_EQ(Full.smax(One), ConstantRange(APInt(16, 0xa),
1153                                           APInt::getSignedMinValue(16)));
1154   EXPECT_EQ(Empty.smax(Empty), Empty);
1155   EXPECT_EQ(Empty.smax(Some), Empty);
1156   EXPECT_EQ(Empty.smax(Wrap), Empty);
1157   EXPECT_EQ(Empty.smax(One), Empty);
1158   EXPECT_EQ(Some.smax(Some), Some);
1159   EXPECT_EQ(Some.smax(Wrap), ConstantRange(APInt(16, 0xa),
1160                                            APInt(16, (uint64_t)INT16_MIN)));
1161   EXPECT_EQ(Some.smax(One), Some);
1162   EXPECT_EQ(Wrap.smax(One), ConstantRange(APInt(16, 0xa),
1163                                           APInt(16, (uint64_t)INT16_MIN)));
1164   EXPECT_EQ(One.smax(One), One);
1165 
1166   TestBinaryOpExhaustive(
1167       [](const ConstantRange &CR1, const ConstantRange &CR2) {
1168         return CR1.smax(CR2);
1169       },
1170       [](const APInt &N1, const APInt &N2) {
1171         return APIntOps::smax(N1, N2);
1172       },
1173       PreferSmallestNonFullSigned);
1174 }
1175 
1176 TEST_F(ConstantRangeTest, UMin) {
1177   EXPECT_EQ(Full.umin(Full), Full);
1178   EXPECT_EQ(Full.umin(Empty), Empty);
1179   EXPECT_EQ(Full.umin(Some), ConstantRange(APInt(16, 0), APInt(16, 0xaaa)));
1180   EXPECT_EQ(Full.umin(Wrap), Full);
1181   EXPECT_EQ(Empty.umin(Empty), Empty);
1182   EXPECT_EQ(Empty.umin(Some), Empty);
1183   EXPECT_EQ(Empty.umin(Wrap), Empty);
1184   EXPECT_EQ(Empty.umin(One), Empty);
1185   EXPECT_EQ(Some.umin(Some), Some);
1186   EXPECT_EQ(Some.umin(Wrap), ConstantRange(APInt(16, 0), APInt(16, 0xaaa)));
1187   EXPECT_EQ(Some.umin(One), One);
1188   EXPECT_EQ(Wrap.umin(Wrap), Wrap);
1189   EXPECT_EQ(Wrap.umin(One), ConstantRange(APInt(16, 0), APInt(16, 0xb)));
1190   EXPECT_EQ(One.umin(One), One);
1191 
1192   TestBinaryOpExhaustive(
1193       [](const ConstantRange &CR1, const ConstantRange &CR2) {
1194         return CR1.umin(CR2);
1195       },
1196       [](const APInt &N1, const APInt &N2) {
1197         return APIntOps::umin(N1, N2);
1198       },
1199       PreferSmallestNonFullUnsigned);
1200 }
1201 
1202 TEST_F(ConstantRangeTest, SMin) {
1203   EXPECT_EQ(Full.smin(Full), Full);
1204   EXPECT_EQ(Full.smin(Empty), Empty);
1205   EXPECT_EQ(Full.smin(Some), ConstantRange(APInt(16, (uint64_t)INT16_MIN),
1206                                            APInt(16, 0xaaa)));
1207   EXPECT_EQ(Full.smin(Wrap), Full);
1208   EXPECT_EQ(Empty.smin(Empty), Empty);
1209   EXPECT_EQ(Empty.smin(Some), Empty);
1210   EXPECT_EQ(Empty.smin(Wrap), Empty);
1211   EXPECT_EQ(Empty.smin(One), Empty);
1212   EXPECT_EQ(Some.smin(Some), Some);
1213   EXPECT_EQ(Some.smin(Wrap), ConstantRange(APInt(16, (uint64_t)INT16_MIN),
1214                                            APInt(16, 0xaaa)));
1215   EXPECT_EQ(Some.smin(One), One);
1216   EXPECT_EQ(Wrap.smin(Wrap), Wrap);
1217   EXPECT_EQ(Wrap.smin(One), ConstantRange(APInt(16, (uint64_t)INT16_MIN),
1218                                           APInt(16, 0xb)));
1219   EXPECT_EQ(One.smin(One), One);
1220 
1221   TestBinaryOpExhaustive(
1222       [](const ConstantRange &CR1, const ConstantRange &CR2) {
1223         return CR1.smin(CR2);
1224       },
1225       [](const APInt &N1, const APInt &N2) {
1226         return APIntOps::smin(N1, N2);
1227       },
1228       PreferSmallestNonFullSigned);
1229 }
1230 
1231 TEST_F(ConstantRangeTest, UDiv) {
1232   EXPECT_EQ(Full.udiv(Full), Full);
1233   EXPECT_EQ(Full.udiv(Empty), Empty);
1234   EXPECT_EQ(Full.udiv(One), ConstantRange(APInt(16, 0),
1235                                           APInt(16, 0xffff / 0xa + 1)));
1236   EXPECT_EQ(Full.udiv(Some), ConstantRange(APInt(16, 0),
1237                                            APInt(16, 0xffff / 0xa + 1)));
1238   EXPECT_EQ(Full.udiv(Wrap), Full);
1239   EXPECT_EQ(Empty.udiv(Empty), Empty);
1240   EXPECT_EQ(Empty.udiv(One), Empty);
1241   EXPECT_EQ(Empty.udiv(Some), Empty);
1242   EXPECT_EQ(Empty.udiv(Wrap), Empty);
1243   EXPECT_EQ(One.udiv(One), ConstantRange(APInt(16, 1)));
1244   EXPECT_EQ(One.udiv(Some), ConstantRange(APInt(16, 0), APInt(16, 2)));
1245   EXPECT_EQ(One.udiv(Wrap), ConstantRange(APInt(16, 0), APInt(16, 0xb)));
1246   EXPECT_EQ(Some.udiv(Some), ConstantRange(APInt(16, 0), APInt(16, 0x111)));
1247   EXPECT_EQ(Some.udiv(Wrap), ConstantRange(APInt(16, 0), APInt(16, 0xaaa)));
1248   EXPECT_EQ(Wrap.udiv(Wrap), Full);
1249 
1250 
1251   ConstantRange Zero(APInt(16, 0));
1252   EXPECT_EQ(Zero.udiv(One), Zero);
1253   EXPECT_EQ(Zero.udiv(Full), Zero);
1254 
1255   EXPECT_EQ(ConstantRange(APInt(16, 0), APInt(16, 99)).udiv(Full),
1256             ConstantRange(APInt(16, 0), APInt(16, 99)));
1257   EXPECT_EQ(ConstantRange(APInt(16, 10), APInt(16, 99)).udiv(Full),
1258             ConstantRange(APInt(16, 0), APInt(16, 99)));
1259 }
1260 
1261 TEST_F(ConstantRangeTest, SDiv) {
1262   unsigned Bits = 4;
1263   EnumerateTwoConstantRanges(Bits, [&](const ConstantRange &CR1,
1264                                        const ConstantRange &CR2) {
1265     // Collect possible results in a bit vector. We store the signed value plus
1266     // a bias to make it unsigned.
1267     int Bias = 1 << (Bits - 1);
1268     BitVector Results(1 << Bits);
1269     ForeachNumInConstantRange(CR1, [&](const APInt &N1) {
1270       ForeachNumInConstantRange(CR2, [&](const APInt &N2) {
1271         // Division by zero is UB.
1272         if (N2 == 0)
1273           return;
1274 
1275         // SignedMin / -1 is UB.
1276         if (N1.isMinSignedValue() && N2.isAllOnes())
1277           return;
1278 
1279         APInt N = N1.sdiv(N2);
1280         Results.set(N.getSExtValue() + Bias);
1281       });
1282     });
1283 
1284     ConstantRange CR = CR1.sdiv(CR2);
1285     if (Results.none()) {
1286       EXPECT_TRUE(CR.isEmptySet());
1287       return;
1288     }
1289 
1290     // If there is a non-full signed envelope, that should be the result.
1291     APInt SMin(Bits, Results.find_first() - Bias);
1292     APInt SMax(Bits, Results.find_last() - Bias);
1293     ConstantRange Envelope = ConstantRange::getNonEmpty(SMin, SMax + 1);
1294     if (!Envelope.isFullSet()) {
1295       EXPECT_EQ(Envelope, CR);
1296       return;
1297     }
1298 
1299     // If the signed envelope is a full set, try to find a smaller sign wrapped
1300     // set that is separated in negative and positive components (or one which
1301     // can also additionally contain zero).
1302     int LastNeg = Results.find_last_in(0, Bias) - Bias;
1303     int LastPos = Results.find_next(Bias) - Bias;
1304     if (Results[Bias]) {
1305       if (LastNeg == -1)
1306         ++LastNeg;
1307       else if (LastPos == 1)
1308         --LastPos;
1309     }
1310 
1311     APInt WMax(Bits, LastNeg);
1312     APInt WMin(Bits, LastPos);
1313     ConstantRange Wrapped = ConstantRange::getNonEmpty(WMin, WMax + 1);
1314     EXPECT_EQ(Wrapped, CR);
1315   });
1316 }
1317 
1318 TEST_F(ConstantRangeTest, URem) {
1319   EXPECT_EQ(Full.urem(Empty), Empty);
1320   EXPECT_EQ(Empty.urem(Full), Empty);
1321   // urem by zero is poison.
1322   EXPECT_EQ(Full.urem(ConstantRange(APInt(16, 0))), Empty);
1323   // urem by full range doesn't contain MaxValue.
1324   EXPECT_EQ(Full.urem(Full), ConstantRange(APInt(16, 0), APInt(16, 0xffff)));
1325   // urem is upper bounded by maximum RHS minus one.
1326   EXPECT_EQ(Full.urem(ConstantRange(APInt(16, 0), APInt(16, 123))),
1327             ConstantRange(APInt(16, 0), APInt(16, 122)));
1328   // urem is upper bounded by maximum LHS.
1329   EXPECT_EQ(ConstantRange(APInt(16, 0), APInt(16, 123)).urem(Full),
1330             ConstantRange(APInt(16, 0), APInt(16, 123)));
1331   // If the LHS is always lower than the RHS, the result is the LHS.
1332   EXPECT_EQ(ConstantRange(APInt(16, 10), APInt(16, 20))
1333                 .urem(ConstantRange(APInt(16, 20), APInt(16, 30))),
1334             ConstantRange(APInt(16, 10), APInt(16, 20)));
1335   // It has to be strictly lower, otherwise the top value may wrap to zero.
1336   EXPECT_EQ(ConstantRange(APInt(16, 10), APInt(16, 20))
1337                 .urem(ConstantRange(APInt(16, 19), APInt(16, 30))),
1338             ConstantRange(APInt(16, 0), APInt(16, 20)));
1339   // [12, 14] % 10 is [2, 4], but we conservatively compute [0, 9].
1340   EXPECT_EQ(ConstantRange(APInt(16, 12), APInt(16, 15))
1341                 .urem(ConstantRange(APInt(16, 10))),
1342             ConstantRange(APInt(16, 0), APInt(16, 10)));
1343 
1344   TestBinaryOpExhaustive(
1345       [](const ConstantRange &CR1, const ConstantRange &CR2) {
1346         return CR1.urem(CR2);
1347       },
1348       [](const APInt &N1, const APInt &N2) -> Optional<APInt> {
1349         if (N2.isZero())
1350           return None;
1351         return N1.urem(N2);
1352       },
1353       PreferSmallest,
1354       CheckSingleElementsOnly);
1355 }
1356 
1357 TEST_F(ConstantRangeTest, SRem) {
1358   EXPECT_EQ(Full.srem(Empty), Empty);
1359   EXPECT_EQ(Empty.srem(Full), Empty);
1360   // srem by zero is UB.
1361   EXPECT_EQ(Full.srem(ConstantRange(APInt(16, 0))), Empty);
1362   // srem by full range doesn't contain SignedMinValue.
1363   EXPECT_EQ(Full.srem(Full), ConstantRange(APInt::getSignedMinValue(16) + 1,
1364                                            APInt::getSignedMinValue(16)));
1365 
1366   ConstantRange PosMod(APInt(16, 10), APInt(16, 21));  // [10, 20]
1367   ConstantRange NegMod(APInt(16, -20), APInt(16, -9)); // [-20, -10]
1368   ConstantRange IntMinMod(APInt::getSignedMinValue(16));
1369 
1370   ConstantRange Expected(16, true);
1371 
1372   // srem is bounded by abs(RHS) minus one.
1373   ConstantRange PosLargeLHS(APInt(16, 0), APInt(16, 41));
1374   Expected = ConstantRange(APInt(16, 0), APInt(16, 20));
1375   EXPECT_EQ(PosLargeLHS.srem(PosMod), Expected);
1376   EXPECT_EQ(PosLargeLHS.srem(NegMod), Expected);
1377   ConstantRange NegLargeLHS(APInt(16, -40), APInt(16, 1));
1378   Expected = ConstantRange(APInt(16, -19), APInt(16, 1));
1379   EXPECT_EQ(NegLargeLHS.srem(PosMod), Expected);
1380   EXPECT_EQ(NegLargeLHS.srem(NegMod), Expected);
1381   ConstantRange PosNegLargeLHS(APInt(16, -32), APInt(16, 38));
1382   Expected = ConstantRange(APInt(16, -19), APInt(16, 20));
1383   EXPECT_EQ(PosNegLargeLHS.srem(PosMod), Expected);
1384   EXPECT_EQ(PosNegLargeLHS.srem(NegMod), Expected);
1385 
1386   // srem is bounded by LHS.
1387   ConstantRange PosLHS(APInt(16, 0), APInt(16, 16));
1388   EXPECT_EQ(PosLHS.srem(PosMod), PosLHS);
1389   EXPECT_EQ(PosLHS.srem(NegMod), PosLHS);
1390   EXPECT_EQ(PosLHS.srem(IntMinMod), PosLHS);
1391   ConstantRange NegLHS(APInt(16, -15), APInt(16, 1));
1392   EXPECT_EQ(NegLHS.srem(PosMod), NegLHS);
1393   EXPECT_EQ(NegLHS.srem(NegMod), NegLHS);
1394   EXPECT_EQ(NegLHS.srem(IntMinMod), NegLHS);
1395   ConstantRange PosNegLHS(APInt(16, -12), APInt(16, 18));
1396   EXPECT_EQ(PosNegLHS.srem(PosMod), PosNegLHS);
1397   EXPECT_EQ(PosNegLHS.srem(NegMod), PosNegLHS);
1398   EXPECT_EQ(PosNegLHS.srem(IntMinMod), PosNegLHS);
1399 
1400   // srem is LHS if it is smaller than RHS.
1401   ConstantRange PosSmallLHS(APInt(16, 3), APInt(16, 8));
1402   EXPECT_EQ(PosSmallLHS.srem(PosMod), PosSmallLHS);
1403   EXPECT_EQ(PosSmallLHS.srem(NegMod), PosSmallLHS);
1404   EXPECT_EQ(PosSmallLHS.srem(IntMinMod), PosSmallLHS);
1405   ConstantRange NegSmallLHS(APInt(16, -7), APInt(16, -2));
1406   EXPECT_EQ(NegSmallLHS.srem(PosMod), NegSmallLHS);
1407   EXPECT_EQ(NegSmallLHS.srem(NegMod), NegSmallLHS);
1408   EXPECT_EQ(NegSmallLHS.srem(IntMinMod), NegSmallLHS);
1409   ConstantRange PosNegSmallLHS(APInt(16, -3), APInt(16, 8));
1410   EXPECT_EQ(PosNegSmallLHS.srem(PosMod), PosNegSmallLHS);
1411   EXPECT_EQ(PosNegSmallLHS.srem(NegMod), PosNegSmallLHS);
1412   EXPECT_EQ(PosNegSmallLHS.srem(IntMinMod), PosNegSmallLHS);
1413 
1414   // Example of a suboptimal result:
1415   // [12, 14] srem 10 is [2, 4], but we conservatively compute [0, 9].
1416   EXPECT_EQ(ConstantRange(APInt(16, 12), APInt(16, 15))
1417                 .srem(ConstantRange(APInt(16, 10))),
1418             ConstantRange(APInt(16, 0), APInt(16, 10)));
1419 
1420   TestBinaryOpExhaustive(
1421       [](const ConstantRange &CR1, const ConstantRange &CR2) {
1422         return CR1.srem(CR2);
1423       },
1424       [](const APInt &N1, const APInt &N2) -> Optional<APInt> {
1425         if (N2.isZero())
1426           return None;
1427         return N1.srem(N2);
1428       },
1429       PreferSmallest,
1430       CheckSingleElementsOnly);
1431 }
1432 
1433 TEST_F(ConstantRangeTest, Shl) {
1434   ConstantRange Some2(APInt(16, 0xfff), APInt(16, 0x8000));
1435   ConstantRange WrapNullMax(APInt(16, 0x1), APInt(16, 0x0));
1436   EXPECT_EQ(Full.shl(Full), Full);
1437   EXPECT_EQ(Full.shl(Empty), Empty);
1438   EXPECT_EQ(Full.shl(One), ConstantRange(APInt(16, 0),
1439                                          APInt(16, 0xfc00) + 1));
1440   EXPECT_EQ(Full.shl(Some), Full);   // TODO: [0, (-1 << 0xa) + 1)
1441   EXPECT_EQ(Full.shl(Wrap), Full);
1442   EXPECT_EQ(Empty.shl(Empty), Empty);
1443   EXPECT_EQ(Empty.shl(One), Empty);
1444   EXPECT_EQ(Empty.shl(Some), Empty);
1445   EXPECT_EQ(Empty.shl(Wrap), Empty);
1446   EXPECT_EQ(One.shl(One), ConstantRange(APInt(16, 0xa << 0xa),
1447                                         APInt(16, (0xa << 0xa) + 1)));
1448   EXPECT_EQ(One.shl(Some), Full);    // TODO: [0xa << 0xa, 0)
1449   EXPECT_EQ(One.shl(Wrap), Full);    // TODO: [0xa, 0xa << 14 + 1)
1450   EXPECT_EQ(Some.shl(Some), Full);   // TODO: [0xa << 0xa, 0xfc01)
1451   EXPECT_EQ(Some.shl(Wrap), Full);   // TODO: [0xa, 0x7ff << 0x5 + 1)
1452   EXPECT_EQ(Wrap.shl(Wrap), Full);
1453   EXPECT_EQ(
1454       Some2.shl(ConstantRange(APInt(16, 0x1))),
1455       ConstantRange(APInt(16, 0xfff << 0x1), APInt(16, 0x7fff << 0x1) + 1));
1456   EXPECT_EQ(One.shl(WrapNullMax), Full);
1457 
1458   TestBinaryOpExhaustive(
1459       [](const ConstantRange &CR1, const ConstantRange &CR2) {
1460         return CR1.shl(CR2);
1461       },
1462       [](const APInt &N1, const APInt &N2) -> Optional<APInt> {
1463         if (N2.uge(N2.getBitWidth()))
1464           return None;
1465         return N1.shl(N2);
1466       },
1467       PreferSmallestUnsigned,
1468       [](const ConstantRange &, const ConstantRange &CR2) {
1469         // We currently only produce precise results for single element RHS.
1470         return CR2.isSingleElement();
1471       });
1472 }
1473 
1474 TEST_F(ConstantRangeTest, Lshr) {
1475   EXPECT_EQ(Full.lshr(Full), Full);
1476   EXPECT_EQ(Full.lshr(Empty), Empty);
1477   EXPECT_EQ(Full.lshr(One), ConstantRange(APInt(16, 0),
1478                                           APInt(16, (0xffff >> 0xa) + 1)));
1479   EXPECT_EQ(Full.lshr(Some), ConstantRange(APInt(16, 0),
1480                                            APInt(16, (0xffff >> 0xa) + 1)));
1481   EXPECT_EQ(Full.lshr(Wrap), Full);
1482   EXPECT_EQ(Empty.lshr(Empty), Empty);
1483   EXPECT_EQ(Empty.lshr(One), Empty);
1484   EXPECT_EQ(Empty.lshr(Some), Empty);
1485   EXPECT_EQ(Empty.lshr(Wrap), Empty);
1486   EXPECT_EQ(One.lshr(One), ConstantRange(APInt(16, 0)));
1487   EXPECT_EQ(One.lshr(Some), ConstantRange(APInt(16, 0)));
1488   EXPECT_EQ(One.lshr(Wrap), ConstantRange(APInt(16, 0), APInt(16, 0xb)));
1489   EXPECT_EQ(Some.lshr(Some), ConstantRange(APInt(16, 0),
1490                                            APInt(16, (0xaaa >> 0xa) + 1)));
1491   EXPECT_EQ(Some.lshr(Wrap), ConstantRange(APInt(16, 0), APInt(16, 0xaaa)));
1492   EXPECT_EQ(Wrap.lshr(Wrap), Full);
1493 }
1494 
1495 TEST_F(ConstantRangeTest, Ashr) {
1496   EXPECT_EQ(Full.ashr(Full), Full);
1497   EXPECT_EQ(Full.ashr(Empty), Empty);
1498   EXPECT_EQ(Full.ashr(One), ConstantRange(APInt(16, 0xffe0),
1499                                           APInt(16, (0x7fff >> 0xa) + 1 )));
1500   ConstantRange Small(APInt(16, 0xa), APInt(16, 0xb));
1501   EXPECT_EQ(Full.ashr(Small), ConstantRange(APInt(16, 0xffe0),
1502                                            APInt(16, (0x7fff >> 0xa) + 1 )));
1503   EXPECT_EQ(Full.ashr(Some), ConstantRange(APInt(16, 0xffe0),
1504                                            APInt(16, (0x7fff >> 0xa) + 1 )));
1505   EXPECT_EQ(Full.ashr(Wrap), Full);
1506   EXPECT_EQ(Empty.ashr(Empty), Empty);
1507   EXPECT_EQ(Empty.ashr(One), Empty);
1508   EXPECT_EQ(Empty.ashr(Some), Empty);
1509   EXPECT_EQ(Empty.ashr(Wrap), Empty);
1510   EXPECT_EQ(One.ashr(One), ConstantRange(APInt(16, 0)));
1511   EXPECT_EQ(One.ashr(Some), ConstantRange(APInt(16, 0)));
1512   EXPECT_EQ(One.ashr(Wrap), ConstantRange(APInt(16, 0), APInt(16, 0xb)));
1513   EXPECT_EQ(Some.ashr(Some), ConstantRange(APInt(16, 0),
1514                                            APInt(16, (0xaaa >> 0xa) + 1)));
1515   EXPECT_EQ(Some.ashr(Wrap), ConstantRange(APInt(16, 0), APInt(16, 0xaaa)));
1516   EXPECT_EQ(Wrap.ashr(Wrap), Full);
1517   ConstantRange Neg(APInt(16, 0xf3f0, true), APInt(16, 0xf7f8, true));
1518   EXPECT_EQ(Neg.ashr(Small), ConstantRange(APInt(16, 0xfffc, true),
1519                                            APInt(16, 0xfffe, true)));
1520 }
1521 
1522 TEST(ConstantRange, MakeAllowedICmpRegion) {
1523   // PR8250
1524   ConstantRange SMax = ConstantRange(APInt::getSignedMaxValue(32));
1525   EXPECT_TRUE(ConstantRange::makeAllowedICmpRegion(ICmpInst::ICMP_SGT, SMax)
1526                   .isEmptySet());
1527 }
1528 
1529 TEST(ConstantRange, MakeSatisfyingICmpRegion) {
1530   ConstantRange LowHalf(APInt(8, 0), APInt(8, 128));
1531   ConstantRange HighHalf(APInt(8, 128), APInt(8, 0));
1532   ConstantRange EmptySet(8, /* isFullSet = */ false);
1533 
1534   EXPECT_EQ(ConstantRange::makeSatisfyingICmpRegion(ICmpInst::ICMP_NE, LowHalf),
1535             HighHalf);
1536 
1537   EXPECT_EQ(
1538       ConstantRange::makeSatisfyingICmpRegion(ICmpInst::ICMP_NE, HighHalf),
1539       LowHalf);
1540 
1541   EXPECT_TRUE(ConstantRange::makeSatisfyingICmpRegion(ICmpInst::ICMP_EQ,
1542                                                       HighHalf).isEmptySet());
1543 
1544   ConstantRange UnsignedSample(APInt(8, 5), APInt(8, 200));
1545 
1546   EXPECT_EQ(ConstantRange::makeSatisfyingICmpRegion(ICmpInst::ICMP_ULT,
1547                                                     UnsignedSample),
1548             ConstantRange(APInt(8, 0), APInt(8, 5)));
1549 
1550   EXPECT_EQ(ConstantRange::makeSatisfyingICmpRegion(ICmpInst::ICMP_ULE,
1551                                                     UnsignedSample),
1552             ConstantRange(APInt(8, 0), APInt(8, 6)));
1553 
1554   EXPECT_EQ(ConstantRange::makeSatisfyingICmpRegion(ICmpInst::ICMP_UGT,
1555                                                     UnsignedSample),
1556             ConstantRange(APInt(8, 200), APInt(8, 0)));
1557 
1558   EXPECT_EQ(ConstantRange::makeSatisfyingICmpRegion(ICmpInst::ICMP_UGE,
1559                                                     UnsignedSample),
1560             ConstantRange(APInt(8, 199), APInt(8, 0)));
1561 
1562   ConstantRange SignedSample(APInt(8, -5), APInt(8, 5));
1563 
1564   EXPECT_EQ(
1565       ConstantRange::makeSatisfyingICmpRegion(ICmpInst::ICMP_SLT, SignedSample),
1566       ConstantRange(APInt(8, -128), APInt(8, -5)));
1567 
1568   EXPECT_EQ(
1569       ConstantRange::makeSatisfyingICmpRegion(ICmpInst::ICMP_SLE, SignedSample),
1570       ConstantRange(APInt(8, -128), APInt(8, -4)));
1571 
1572   EXPECT_EQ(
1573       ConstantRange::makeSatisfyingICmpRegion(ICmpInst::ICMP_SGT, SignedSample),
1574       ConstantRange(APInt(8, 5), APInt(8, -128)));
1575 
1576   EXPECT_EQ(
1577       ConstantRange::makeSatisfyingICmpRegion(ICmpInst::ICMP_SGE, SignedSample),
1578       ConstantRange(APInt(8, 4), APInt(8, -128)));
1579 }
1580 
1581 void ICmpTestImpl(CmpInst::Predicate Pred) {
1582   unsigned Bits = 4;
1583   EnumerateTwoConstantRanges(
1584       Bits, [&](const ConstantRange &CR1, const ConstantRange &CR2) {
1585         bool Exhaustive = true;
1586         ForeachNumInConstantRange(CR1, [&](const APInt &N1) {
1587           ForeachNumInConstantRange(CR2, [&](const APInt &N2) {
1588             Exhaustive &= ICmpInst::compare(N1, N2, Pred);
1589           });
1590         });
1591         EXPECT_EQ(CR1.icmp(Pred, CR2), Exhaustive);
1592       });
1593 }
1594 
1595 TEST(ConstantRange, ICmp) {
1596   for (auto Pred : ICmpInst::predicates())
1597     ICmpTestImpl(Pred);
1598 }
1599 
1600 TEST(ConstantRange, MakeGuaranteedNoWrapRegion) {
1601   const int IntMin4Bits = 8;
1602   const int IntMax4Bits = 7;
1603   typedef OverflowingBinaryOperator OBO;
1604 
1605   for (int Const : {0, -1, -2, 1, 2, IntMin4Bits, IntMax4Bits}) {
1606     APInt C(4, Const, true /* = isSigned */);
1607 
1608     auto NUWRegion = ConstantRange::makeGuaranteedNoWrapRegion(
1609         Instruction::Add, C, OBO::NoUnsignedWrap);
1610 
1611     EXPECT_FALSE(NUWRegion.isEmptySet());
1612 
1613     auto NSWRegion = ConstantRange::makeGuaranteedNoWrapRegion(
1614         Instruction::Add, C, OBO::NoSignedWrap);
1615 
1616     EXPECT_FALSE(NSWRegion.isEmptySet());
1617 
1618     for (APInt I = NUWRegion.getLower(), E = NUWRegion.getUpper(); I != E;
1619          ++I) {
1620       bool Overflow = false;
1621       (void)I.uadd_ov(C, Overflow);
1622       EXPECT_FALSE(Overflow);
1623     }
1624 
1625     for (APInt I = NSWRegion.getLower(), E = NSWRegion.getUpper(); I != E;
1626          ++I) {
1627       bool Overflow = false;
1628       (void)I.sadd_ov(C, Overflow);
1629       EXPECT_FALSE(Overflow);
1630     }
1631   }
1632 
1633   for (int Const : {0, -1, -2, 1, 2, IntMin4Bits, IntMax4Bits}) {
1634     APInt C(4, Const, true /* = isSigned */);
1635 
1636     auto NUWRegion = ConstantRange::makeGuaranteedNoWrapRegion(
1637         Instruction::Sub, C, OBO::NoUnsignedWrap);
1638 
1639     EXPECT_FALSE(NUWRegion.isEmptySet());
1640 
1641     auto NSWRegion = ConstantRange::makeGuaranteedNoWrapRegion(
1642         Instruction::Sub, C, OBO::NoSignedWrap);
1643 
1644     EXPECT_FALSE(NSWRegion.isEmptySet());
1645 
1646     for (APInt I = NUWRegion.getLower(), E = NUWRegion.getUpper(); I != E;
1647          ++I) {
1648       bool Overflow = false;
1649       (void)I.usub_ov(C, Overflow);
1650       EXPECT_FALSE(Overflow);
1651     }
1652 
1653     for (APInt I = NSWRegion.getLower(), E = NSWRegion.getUpper(); I != E;
1654          ++I) {
1655       bool Overflow = false;
1656       (void)I.ssub_ov(C, Overflow);
1657       EXPECT_FALSE(Overflow);
1658     }
1659   }
1660 
1661   auto NSWForAllValues = ConstantRange::makeGuaranteedNoWrapRegion(
1662       Instruction::Add, ConstantRange(32, /* isFullSet = */ true),
1663       OBO::NoSignedWrap);
1664   EXPECT_TRUE(NSWForAllValues.isSingleElement() &&
1665               NSWForAllValues.getSingleElement()->isMinValue());
1666 
1667   NSWForAllValues = ConstantRange::makeGuaranteedNoWrapRegion(
1668       Instruction::Sub, ConstantRange(32, /* isFullSet = */ true),
1669       OBO::NoSignedWrap);
1670   EXPECT_TRUE(NSWForAllValues.isSingleElement() &&
1671               NSWForAllValues.getSingleElement()->isMaxValue());
1672 
1673   auto NUWForAllValues = ConstantRange::makeGuaranteedNoWrapRegion(
1674       Instruction::Add, ConstantRange(32, /* isFullSet = */ true),
1675       OBO::NoUnsignedWrap);
1676   EXPECT_TRUE(NUWForAllValues.isSingleElement() &&
1677               NUWForAllValues.getSingleElement()->isMinValue());
1678 
1679   NUWForAllValues = ConstantRange::makeGuaranteedNoWrapRegion(
1680       Instruction::Sub, ConstantRange(32, /* isFullSet = */ true),
1681       OBO::NoUnsignedWrap);
1682   EXPECT_TRUE(NUWForAllValues.isSingleElement() &&
1683               NUWForAllValues.getSingleElement()->isMaxValue());
1684 
1685   EXPECT_TRUE(ConstantRange::makeGuaranteedNoWrapRegion(
1686       Instruction::Add, APInt(32, 0), OBO::NoUnsignedWrap).isFullSet());
1687   EXPECT_TRUE(ConstantRange::makeGuaranteedNoWrapRegion(
1688       Instruction::Add, APInt(32, 0), OBO::NoSignedWrap).isFullSet());
1689   EXPECT_TRUE(ConstantRange::makeGuaranteedNoWrapRegion(
1690       Instruction::Sub, APInt(32, 0), OBO::NoUnsignedWrap).isFullSet());
1691   EXPECT_TRUE(ConstantRange::makeGuaranteedNoWrapRegion(
1692       Instruction::Sub, APInt(32, 0), OBO::NoSignedWrap).isFullSet());
1693 
1694   ConstantRange OneToFive(APInt(32, 1), APInt(32, 6));
1695   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1696                 Instruction::Add, OneToFive, OBO::NoSignedWrap),
1697             ConstantRange(APInt::getSignedMinValue(32),
1698                           APInt::getSignedMaxValue(32) - 4));
1699   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1700                 Instruction::Add, OneToFive, OBO::NoUnsignedWrap),
1701             ConstantRange(APInt::getMinValue(32), APInt::getMinValue(32) - 5));
1702   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1703                 Instruction::Sub, OneToFive, OBO::NoSignedWrap),
1704             ConstantRange(APInt::getSignedMinValue(32) + 5,
1705                           APInt::getSignedMinValue(32)));
1706   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1707                 Instruction::Sub, OneToFive, OBO::NoUnsignedWrap),
1708             ConstantRange(APInt::getMinValue(32) + 5, APInt::getMinValue(32)));
1709 
1710   ConstantRange MinusFiveToMinusTwo(APInt(32, -5), APInt(32, -1));
1711   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1712                 Instruction::Add, MinusFiveToMinusTwo, OBO::NoSignedWrap),
1713             ConstantRange(APInt::getSignedMinValue(32) + 5,
1714                           APInt::getSignedMinValue(32)));
1715   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1716                 Instruction::Add, MinusFiveToMinusTwo, OBO::NoUnsignedWrap),
1717             ConstantRange(APInt(32, 0), APInt(32, 2)));
1718   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1719                 Instruction::Sub, MinusFiveToMinusTwo, OBO::NoSignedWrap),
1720             ConstantRange(APInt::getSignedMinValue(32),
1721                           APInt::getSignedMaxValue(32) - 4));
1722   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1723                 Instruction::Sub, MinusFiveToMinusTwo, OBO::NoUnsignedWrap),
1724             ConstantRange(APInt::getMaxValue(32) - 1,
1725                           APInt::getMinValue(32)));
1726 
1727   ConstantRange MinusOneToOne(APInt(32, -1), APInt(32, 2));
1728   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1729                 Instruction::Add, MinusOneToOne, OBO::NoSignedWrap),
1730             ConstantRange(APInt::getSignedMinValue(32) + 1,
1731                           APInt::getSignedMinValue(32) - 1));
1732   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1733                 Instruction::Add, MinusOneToOne, OBO::NoUnsignedWrap),
1734             ConstantRange(APInt(32, 0), APInt(32, 1)));
1735   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1736                 Instruction::Sub, MinusOneToOne, OBO::NoSignedWrap),
1737             ConstantRange(APInt::getSignedMinValue(32) + 1,
1738                           APInt::getSignedMinValue(32) - 1));
1739   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1740                 Instruction::Sub, MinusOneToOne, OBO::NoUnsignedWrap),
1741             ConstantRange(APInt::getMaxValue(32),
1742                           APInt::getMinValue(32)));
1743 
1744   ConstantRange One(APInt(32, 1), APInt(32, 2));
1745   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1746                 Instruction::Add, One, OBO::NoSignedWrap),
1747             ConstantRange(APInt::getSignedMinValue(32),
1748                           APInt::getSignedMaxValue(32)));
1749   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1750                 Instruction::Add, One, OBO::NoUnsignedWrap),
1751             ConstantRange(APInt::getMinValue(32), APInt::getMaxValue(32)));
1752   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1753                 Instruction::Sub, One, OBO::NoSignedWrap),
1754             ConstantRange(APInt::getSignedMinValue(32) + 1,
1755                           APInt::getSignedMinValue(32)));
1756   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1757                 Instruction::Sub, One, OBO::NoUnsignedWrap),
1758             ConstantRange(APInt::getMinValue(32) + 1, APInt::getMinValue(32)));
1759 
1760   ConstantRange OneLessThanBitWidth(APInt(32, 0), APInt(32, 31) + 1);
1761   ConstantRange UpToBitWidth(APInt(32, 0), APInt(32, 32) + 1);
1762   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1763                 Instruction::Shl, UpToBitWidth, OBO::NoUnsignedWrap),
1764             ConstantRange::makeGuaranteedNoWrapRegion(
1765                 Instruction::Shl, OneLessThanBitWidth, OBO::NoUnsignedWrap));
1766   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1767                 Instruction::Shl, UpToBitWidth, OBO::NoSignedWrap),
1768             ConstantRange::makeGuaranteedNoWrapRegion(
1769                 Instruction::Shl, OneLessThanBitWidth, OBO::NoSignedWrap));
1770   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1771                 Instruction::Shl, UpToBitWidth, OBO::NoUnsignedWrap),
1772             ConstantRange(APInt(32, 0), APInt(32, 1) + 1));
1773   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1774                 Instruction::Shl, UpToBitWidth, OBO::NoSignedWrap),
1775             ConstantRange(APInt(32, -1), APInt(32, 0) + 1));
1776 
1777   EXPECT_EQ(
1778       ConstantRange::makeGuaranteedNoWrapRegion(
1779           Instruction::Shl, ConstantRange::getFull(32), OBO::NoUnsignedWrap),
1780       ConstantRange::makeGuaranteedNoWrapRegion(
1781           Instruction::Shl, OneLessThanBitWidth, OBO::NoUnsignedWrap));
1782   EXPECT_EQ(
1783       ConstantRange::makeGuaranteedNoWrapRegion(
1784           Instruction::Shl, ConstantRange::getFull(32), OBO::NoSignedWrap),
1785       ConstantRange::makeGuaranteedNoWrapRegion(
1786           Instruction::Shl, OneLessThanBitWidth, OBO::NoSignedWrap));
1787 
1788   ConstantRange IllegalShAmt(APInt(32, 32), APInt(32, 0) + 1);
1789   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1790                 Instruction::Shl, IllegalShAmt, OBO::NoUnsignedWrap),
1791             ConstantRange::getFull(32));
1792   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1793                 Instruction::Shl, IllegalShAmt, OBO::NoSignedWrap),
1794             ConstantRange::getFull(32));
1795 
1796   EXPECT_EQ(
1797       ConstantRange::makeGuaranteedNoWrapRegion(
1798           Instruction::Shl, ConstantRange(APInt(32, -32), APInt(32, 16) + 1),
1799           OBO::NoUnsignedWrap),
1800       ConstantRange::makeGuaranteedNoWrapRegion(
1801           Instruction::Shl, ConstantRange(APInt(32, 0), APInt(32, 16) + 1),
1802           OBO::NoUnsignedWrap));
1803   EXPECT_EQ(
1804       ConstantRange::makeGuaranteedNoWrapRegion(
1805           Instruction::Shl, ConstantRange(APInt(32, -32), APInt(32, 16) + 1),
1806           OBO::NoSignedWrap),
1807       ConstantRange::makeGuaranteedNoWrapRegion(
1808           Instruction::Shl, ConstantRange(APInt(32, 0), APInt(32, 16) + 1),
1809           OBO::NoSignedWrap));
1810 
1811   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1812                 Instruction::Shl,
1813                 ConstantRange(APInt(32, -32), APInt(32, 16) + 1),
1814                 OBO::NoUnsignedWrap),
1815             ConstantRange(APInt(32, 0), APInt(32, 65535) + 1));
1816   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1817                 Instruction::Shl,
1818                 ConstantRange(APInt(32, -32), APInt(32, 16) + 1),
1819                 OBO::NoSignedWrap),
1820             ConstantRange(APInt(32, -32768), APInt(32, 32767) + 1));
1821 }
1822 
1823 template<typename Fn>
1824 void TestNoWrapRegionExhaustive(Instruction::BinaryOps BinOp,
1825                                 unsigned NoWrapKind, Fn OverflowFn) {
1826   unsigned Bits = 5;
1827   EnumerateConstantRanges(Bits, [&](const ConstantRange &CR) {
1828     if (CR.isEmptySet())
1829       return;
1830     if (Instruction::isShift(BinOp) && CR.getUnsignedMax().uge(Bits))
1831       return;
1832 
1833     ConstantRange NoWrap =
1834         ConstantRange::makeGuaranteedNoWrapRegion(BinOp, CR, NoWrapKind);
1835     EnumerateAPInts(Bits, [&](const APInt &N1) {
1836       bool NoOverflow = true;
1837       bool Overflow = true;
1838       ForeachNumInConstantRange(CR, [&](const APInt &N2) {
1839         if (OverflowFn(N1, N2))
1840           NoOverflow = false;
1841         else
1842           Overflow = false;
1843       });
1844       EXPECT_EQ(NoOverflow, NoWrap.contains(N1));
1845 
1846       // The no-wrap range is exact for single-element ranges.
1847       if (CR.isSingleElement()) {
1848         EXPECT_EQ(Overflow, !NoWrap.contains(N1));
1849       }
1850     });
1851   });
1852 }
1853 
1854 // Show that makeGuaranteedNoWrapRegion() is maximal, and for single-element
1855 // ranges also exact.
1856 TEST(ConstantRange, NoWrapRegionExhaustive) {
1857   TestNoWrapRegionExhaustive(
1858       Instruction::Add, OverflowingBinaryOperator::NoUnsignedWrap,
1859       [](const APInt &N1, const APInt &N2) {
1860         bool Overflow;
1861         (void) N1.uadd_ov(N2, Overflow);
1862         return Overflow;
1863       });
1864   TestNoWrapRegionExhaustive(
1865       Instruction::Add, OverflowingBinaryOperator::NoSignedWrap,
1866       [](const APInt &N1, const APInt &N2) {
1867         bool Overflow;
1868         (void) N1.sadd_ov(N2, Overflow);
1869         return Overflow;
1870       });
1871   TestNoWrapRegionExhaustive(
1872       Instruction::Sub, OverflowingBinaryOperator::NoUnsignedWrap,
1873       [](const APInt &N1, const APInt &N2) {
1874         bool Overflow;
1875         (void) N1.usub_ov(N2, Overflow);
1876         return Overflow;
1877       });
1878   TestNoWrapRegionExhaustive(
1879       Instruction::Sub, OverflowingBinaryOperator::NoSignedWrap,
1880       [](const APInt &N1, const APInt &N2) {
1881         bool Overflow;
1882         (void) N1.ssub_ov(N2, Overflow);
1883         return Overflow;
1884       });
1885   TestNoWrapRegionExhaustive(
1886       Instruction::Mul, OverflowingBinaryOperator::NoUnsignedWrap,
1887       [](const APInt &N1, const APInt &N2) {
1888         bool Overflow;
1889         (void) N1.umul_ov(N2, Overflow);
1890         return Overflow;
1891       });
1892   TestNoWrapRegionExhaustive(
1893       Instruction::Mul, OverflowingBinaryOperator::NoSignedWrap,
1894       [](const APInt &N1, const APInt &N2) {
1895         bool Overflow;
1896         (void) N1.smul_ov(N2, Overflow);
1897         return Overflow;
1898       });
1899   TestNoWrapRegionExhaustive(Instruction::Shl,
1900                              OverflowingBinaryOperator::NoUnsignedWrap,
1901                              [](const APInt &N1, const APInt &N2) {
1902                                bool Overflow;
1903                                (void)N1.ushl_ov(N2, Overflow);
1904                                return Overflow;
1905                              });
1906   TestNoWrapRegionExhaustive(Instruction::Shl,
1907                              OverflowingBinaryOperator::NoSignedWrap,
1908                              [](const APInt &N1, const APInt &N2) {
1909                                bool Overflow;
1910                                (void)N1.sshl_ov(N2, Overflow);
1911                                return Overflow;
1912                              });
1913 }
1914 
1915 TEST(ConstantRange, GetEquivalentICmp) {
1916   APInt RHS;
1917   CmpInst::Predicate Pred;
1918 
1919   EXPECT_TRUE(ConstantRange(APInt::getMinValue(32), APInt(32, 100))
1920                   .getEquivalentICmp(Pred, RHS));
1921   EXPECT_EQ(Pred, CmpInst::ICMP_ULT);
1922   EXPECT_EQ(RHS, APInt(32, 100));
1923 
1924   EXPECT_TRUE(ConstantRange(APInt::getSignedMinValue(32), APInt(32, 100))
1925                   .getEquivalentICmp(Pred, RHS));
1926   EXPECT_EQ(Pred, CmpInst::ICMP_SLT);
1927   EXPECT_EQ(RHS, APInt(32, 100));
1928 
1929   EXPECT_TRUE(ConstantRange(APInt(32, 100), APInt::getMinValue(32))
1930                   .getEquivalentICmp(Pred, RHS));
1931   EXPECT_EQ(Pred, CmpInst::ICMP_UGE);
1932   EXPECT_EQ(RHS, APInt(32, 100));
1933 
1934   EXPECT_TRUE(ConstantRange(APInt(32, 100), APInt::getSignedMinValue(32))
1935                   .getEquivalentICmp(Pred, RHS));
1936   EXPECT_EQ(Pred, CmpInst::ICMP_SGE);
1937   EXPECT_EQ(RHS, APInt(32, 100));
1938 
1939   EXPECT_TRUE(
1940       ConstantRange(32, /*isFullSet=*/true).getEquivalentICmp(Pred, RHS));
1941   EXPECT_EQ(Pred, CmpInst::ICMP_UGE);
1942   EXPECT_EQ(RHS, APInt(32, 0));
1943 
1944   EXPECT_TRUE(
1945       ConstantRange(32, /*isFullSet=*/false).getEquivalentICmp(Pred, RHS));
1946   EXPECT_EQ(Pred, CmpInst::ICMP_ULT);
1947   EXPECT_EQ(RHS, APInt(32, 0));
1948 
1949   EXPECT_FALSE(ConstantRange(APInt(32, 100), APInt(32, 200))
1950                    .getEquivalentICmp(Pred, RHS));
1951 
1952   EXPECT_FALSE(ConstantRange(APInt::getSignedMinValue(32) - APInt(32, 100),
1953                              APInt::getSignedMinValue(32) + APInt(32, 100))
1954                    .getEquivalentICmp(Pred, RHS));
1955 
1956   EXPECT_FALSE(ConstantRange(APInt::getMinValue(32) - APInt(32, 100),
1957                              APInt::getMinValue(32) + APInt(32, 100))
1958                    .getEquivalentICmp(Pred, RHS));
1959 
1960   EXPECT_TRUE(ConstantRange(APInt(32, 100)).getEquivalentICmp(Pred, RHS));
1961   EXPECT_EQ(Pred, CmpInst::ICMP_EQ);
1962   EXPECT_EQ(RHS, APInt(32, 100));
1963 
1964   EXPECT_TRUE(
1965       ConstantRange(APInt(32, 100)).inverse().getEquivalentICmp(Pred, RHS));
1966   EXPECT_EQ(Pred, CmpInst::ICMP_NE);
1967   EXPECT_EQ(RHS, APInt(32, 100));
1968 
1969   EXPECT_TRUE(
1970       ConstantRange(APInt(512, 100)).inverse().getEquivalentICmp(Pred, RHS));
1971   EXPECT_EQ(Pred, CmpInst::ICMP_NE);
1972   EXPECT_EQ(RHS, APInt(512, 100));
1973 
1974   // NB!  It would be correct for the following four calls to getEquivalentICmp
1975   // to return ordered predicates like CmpInst::ICMP_ULT or CmpInst::ICMP_UGT.
1976   // However, that's not the case today.
1977 
1978   EXPECT_TRUE(ConstantRange(APInt(32, 0)).getEquivalentICmp(Pred, RHS));
1979   EXPECT_EQ(Pred, CmpInst::ICMP_EQ);
1980   EXPECT_EQ(RHS, APInt(32, 0));
1981 
1982   EXPECT_TRUE(
1983       ConstantRange(APInt(32, 0)).inverse().getEquivalentICmp(Pred, RHS));
1984   EXPECT_EQ(Pred, CmpInst::ICMP_NE);
1985   EXPECT_EQ(RHS, APInt(32, 0));
1986 
1987   EXPECT_TRUE(ConstantRange(APInt(32, -1)).getEquivalentICmp(Pred, RHS));
1988   EXPECT_EQ(Pred, CmpInst::ICMP_EQ);
1989   EXPECT_EQ(RHS, APInt(32, -1));
1990 
1991   EXPECT_TRUE(
1992       ConstantRange(APInt(32, -1)).inverse().getEquivalentICmp(Pred, RHS));
1993   EXPECT_EQ(Pred, CmpInst::ICMP_NE);
1994   EXPECT_EQ(RHS, APInt(32, -1));
1995 
1996   unsigned Bits = 4;
1997   EnumerateConstantRanges(Bits, [Bits](const ConstantRange &CR) {
1998     CmpInst::Predicate Pred;
1999     APInt RHS, Offset;
2000     CR.getEquivalentICmp(Pred, RHS, Offset);
2001     EnumerateAPInts(Bits, [&](const APInt &N) {
2002       bool Result = ICmpInst::compare(N + Offset, RHS, Pred);
2003       EXPECT_EQ(CR.contains(N), Result);
2004     });
2005 
2006     if (CR.getEquivalentICmp(Pred, RHS)) {
2007       EnumerateAPInts(Bits, [&](const APInt &N) {
2008         bool Result = ICmpInst::compare(N, RHS, Pred);
2009         EXPECT_EQ(CR.contains(N), Result);
2010       });
2011     }
2012   });
2013 }
2014 
2015 #define EXPECT_MAY_OVERFLOW(op) \
2016   EXPECT_EQ(ConstantRange::OverflowResult::MayOverflow, (op))
2017 #define EXPECT_ALWAYS_OVERFLOWS_LOW(op) \
2018   EXPECT_EQ(ConstantRange::OverflowResult::AlwaysOverflowsLow, (op))
2019 #define EXPECT_ALWAYS_OVERFLOWS_HIGH(op) \
2020   EXPECT_EQ(ConstantRange::OverflowResult::AlwaysOverflowsHigh, (op))
2021 #define EXPECT_NEVER_OVERFLOWS(op) \
2022   EXPECT_EQ(ConstantRange::OverflowResult::NeverOverflows, (op))
2023 
2024 TEST_F(ConstantRangeTest, UnsignedAddOverflow) {
2025   // Ill-defined - may overflow is a conservative result.
2026   EXPECT_MAY_OVERFLOW(Some.unsignedAddMayOverflow(Empty));
2027   EXPECT_MAY_OVERFLOW(Empty.unsignedAddMayOverflow(Some));
2028 
2029   // Never overflow despite one full/wrap set.
2030   ConstantRange Zero(APInt::getZero(16));
2031   EXPECT_NEVER_OVERFLOWS(Full.unsignedAddMayOverflow(Zero));
2032   EXPECT_NEVER_OVERFLOWS(Wrap.unsignedAddMayOverflow(Zero));
2033   EXPECT_NEVER_OVERFLOWS(Zero.unsignedAddMayOverflow(Full));
2034   EXPECT_NEVER_OVERFLOWS(Zero.unsignedAddMayOverflow(Wrap));
2035 
2036   // But usually full/wrap always may overflow.
2037   EXPECT_MAY_OVERFLOW(Full.unsignedAddMayOverflow(One));
2038   EXPECT_MAY_OVERFLOW(Wrap.unsignedAddMayOverflow(One));
2039   EXPECT_MAY_OVERFLOW(One.unsignedAddMayOverflow(Full));
2040   EXPECT_MAY_OVERFLOW(One.unsignedAddMayOverflow(Wrap));
2041 
2042   ConstantRange A(APInt(16, 0xfd00), APInt(16, 0xfe00));
2043   ConstantRange B1(APInt(16, 0x0100), APInt(16, 0x0201));
2044   ConstantRange B2(APInt(16, 0x0100), APInt(16, 0x0202));
2045   EXPECT_NEVER_OVERFLOWS(A.unsignedAddMayOverflow(B1));
2046   EXPECT_MAY_OVERFLOW(A.unsignedAddMayOverflow(B2));
2047   EXPECT_NEVER_OVERFLOWS(B1.unsignedAddMayOverflow(A));
2048   EXPECT_MAY_OVERFLOW(B2.unsignedAddMayOverflow(A));
2049 
2050   ConstantRange C1(APInt(16, 0x0299), APInt(16, 0x0400));
2051   ConstantRange C2(APInt(16, 0x0300), APInt(16, 0x0400));
2052   EXPECT_MAY_OVERFLOW(A.unsignedAddMayOverflow(C1));
2053   EXPECT_ALWAYS_OVERFLOWS_HIGH(A.unsignedAddMayOverflow(C2));
2054   EXPECT_MAY_OVERFLOW(C1.unsignedAddMayOverflow(A));
2055   EXPECT_ALWAYS_OVERFLOWS_HIGH(C2.unsignedAddMayOverflow(A));
2056 }
2057 
2058 TEST_F(ConstantRangeTest, UnsignedSubOverflow) {
2059   // Ill-defined - may overflow is a conservative result.
2060   EXPECT_MAY_OVERFLOW(Some.unsignedSubMayOverflow(Empty));
2061   EXPECT_MAY_OVERFLOW(Empty.unsignedSubMayOverflow(Some));
2062 
2063   // Never overflow despite one full/wrap set.
2064   ConstantRange Zero(APInt::getZero(16));
2065   ConstantRange Max(APInt::getAllOnes(16));
2066   EXPECT_NEVER_OVERFLOWS(Full.unsignedSubMayOverflow(Zero));
2067   EXPECT_NEVER_OVERFLOWS(Wrap.unsignedSubMayOverflow(Zero));
2068   EXPECT_NEVER_OVERFLOWS(Max.unsignedSubMayOverflow(Full));
2069   EXPECT_NEVER_OVERFLOWS(Max.unsignedSubMayOverflow(Wrap));
2070 
2071   // But usually full/wrap always may overflow.
2072   EXPECT_MAY_OVERFLOW(Full.unsignedSubMayOverflow(One));
2073   EXPECT_MAY_OVERFLOW(Wrap.unsignedSubMayOverflow(One));
2074   EXPECT_MAY_OVERFLOW(One.unsignedSubMayOverflow(Full));
2075   EXPECT_MAY_OVERFLOW(One.unsignedSubMayOverflow(Wrap));
2076 
2077   ConstantRange A(APInt(16, 0x0000), APInt(16, 0x0100));
2078   ConstantRange B(APInt(16, 0x0100), APInt(16, 0x0200));
2079   EXPECT_NEVER_OVERFLOWS(B.unsignedSubMayOverflow(A));
2080   EXPECT_ALWAYS_OVERFLOWS_LOW(A.unsignedSubMayOverflow(B));
2081 
2082   ConstantRange A1(APInt(16, 0x0000), APInt(16, 0x0101));
2083   ConstantRange B1(APInt(16, 0x0100), APInt(16, 0x0201));
2084   EXPECT_NEVER_OVERFLOWS(B1.unsignedSubMayOverflow(A1));
2085   EXPECT_MAY_OVERFLOW(A1.unsignedSubMayOverflow(B1));
2086 
2087   ConstantRange A2(APInt(16, 0x0000), APInt(16, 0x0102));
2088   ConstantRange B2(APInt(16, 0x0100), APInt(16, 0x0202));
2089   EXPECT_MAY_OVERFLOW(B2.unsignedSubMayOverflow(A2));
2090   EXPECT_MAY_OVERFLOW(A2.unsignedSubMayOverflow(B2));
2091 }
2092 
2093 TEST_F(ConstantRangeTest, SignedAddOverflow) {
2094   // Ill-defined - may overflow is a conservative result.
2095   EXPECT_MAY_OVERFLOW(Some.signedAddMayOverflow(Empty));
2096   EXPECT_MAY_OVERFLOW(Empty.signedAddMayOverflow(Some));
2097 
2098   // Never overflow despite one full/wrap set.
2099   ConstantRange Zero(APInt::getZero(16));
2100   EXPECT_NEVER_OVERFLOWS(Full.signedAddMayOverflow(Zero));
2101   EXPECT_NEVER_OVERFLOWS(Wrap.signedAddMayOverflow(Zero));
2102   EXPECT_NEVER_OVERFLOWS(Zero.signedAddMayOverflow(Full));
2103   EXPECT_NEVER_OVERFLOWS(Zero.signedAddMayOverflow(Wrap));
2104 
2105   // But usually full/wrap always may overflow.
2106   EXPECT_MAY_OVERFLOW(Full.signedAddMayOverflow(One));
2107   EXPECT_MAY_OVERFLOW(Wrap.signedAddMayOverflow(One));
2108   EXPECT_MAY_OVERFLOW(One.signedAddMayOverflow(Full));
2109   EXPECT_MAY_OVERFLOW(One.signedAddMayOverflow(Wrap));
2110 
2111   ConstantRange A(APInt(16, 0x7d00), APInt(16, 0x7e00));
2112   ConstantRange B1(APInt(16, 0x0100), APInt(16, 0x0201));
2113   ConstantRange B2(APInt(16, 0x0100), APInt(16, 0x0202));
2114   EXPECT_NEVER_OVERFLOWS(A.signedAddMayOverflow(B1));
2115   EXPECT_MAY_OVERFLOW(A.signedAddMayOverflow(B2));
2116   ConstantRange B3(APInt(16, 0x8000), APInt(16, 0x0201));
2117   ConstantRange B4(APInt(16, 0x8000), APInt(16, 0x0202));
2118   EXPECT_NEVER_OVERFLOWS(A.signedAddMayOverflow(B3));
2119   EXPECT_MAY_OVERFLOW(A.signedAddMayOverflow(B4));
2120   ConstantRange B5(APInt(16, 0x0299), APInt(16, 0x0400));
2121   ConstantRange B6(APInt(16, 0x0300), APInt(16, 0x0400));
2122   EXPECT_MAY_OVERFLOW(A.signedAddMayOverflow(B5));
2123   EXPECT_ALWAYS_OVERFLOWS_HIGH(A.signedAddMayOverflow(B6));
2124 
2125   ConstantRange C(APInt(16, 0x8200), APInt(16, 0x8300));
2126   ConstantRange D1(APInt(16, 0xfe00), APInt(16, 0xff00));
2127   ConstantRange D2(APInt(16, 0xfd99), APInt(16, 0xff00));
2128   EXPECT_NEVER_OVERFLOWS(C.signedAddMayOverflow(D1));
2129   EXPECT_MAY_OVERFLOW(C.signedAddMayOverflow(D2));
2130   ConstantRange D3(APInt(16, 0xfe00), APInt(16, 0x8000));
2131   ConstantRange D4(APInt(16, 0xfd99), APInt(16, 0x8000));
2132   EXPECT_NEVER_OVERFLOWS(C.signedAddMayOverflow(D3));
2133   EXPECT_MAY_OVERFLOW(C.signedAddMayOverflow(D4));
2134   ConstantRange D5(APInt(16, 0xfc00), APInt(16, 0xfd02));
2135   ConstantRange D6(APInt(16, 0xfc00), APInt(16, 0xfd01));
2136   EXPECT_MAY_OVERFLOW(C.signedAddMayOverflow(D5));
2137   EXPECT_ALWAYS_OVERFLOWS_LOW(C.signedAddMayOverflow(D6));
2138 
2139   ConstantRange E(APInt(16, 0xff00), APInt(16, 0x0100));
2140   EXPECT_NEVER_OVERFLOWS(E.signedAddMayOverflow(E));
2141   ConstantRange F(APInt(16, 0xf000), APInt(16, 0x7000));
2142   EXPECT_MAY_OVERFLOW(F.signedAddMayOverflow(F));
2143 }
2144 
2145 TEST_F(ConstantRangeTest, SignedSubOverflow) {
2146   // Ill-defined - may overflow is a conservative result.
2147   EXPECT_MAY_OVERFLOW(Some.signedSubMayOverflow(Empty));
2148   EXPECT_MAY_OVERFLOW(Empty.signedSubMayOverflow(Some));
2149 
2150   // Never overflow despite one full/wrap set.
2151   ConstantRange Zero(APInt::getZero(16));
2152   EXPECT_NEVER_OVERFLOWS(Full.signedSubMayOverflow(Zero));
2153   EXPECT_NEVER_OVERFLOWS(Wrap.signedSubMayOverflow(Zero));
2154 
2155   // But usually full/wrap always may overflow.
2156   EXPECT_MAY_OVERFLOW(Full.signedSubMayOverflow(One));
2157   EXPECT_MAY_OVERFLOW(Wrap.signedSubMayOverflow(One));
2158   EXPECT_MAY_OVERFLOW(One.signedSubMayOverflow(Full));
2159   EXPECT_MAY_OVERFLOW(One.signedSubMayOverflow(Wrap));
2160 
2161   ConstantRange A(APInt(16, 0x7d00), APInt(16, 0x7e00));
2162   ConstantRange B1(APInt(16, 0xfe00), APInt(16, 0xff00));
2163   ConstantRange B2(APInt(16, 0xfd99), APInt(16, 0xff00));
2164   EXPECT_NEVER_OVERFLOWS(A.signedSubMayOverflow(B1));
2165   EXPECT_MAY_OVERFLOW(A.signedSubMayOverflow(B2));
2166   ConstantRange B3(APInt(16, 0xfc00), APInt(16, 0xfd02));
2167   ConstantRange B4(APInt(16, 0xfc00), APInt(16, 0xfd01));
2168   EXPECT_MAY_OVERFLOW(A.signedSubMayOverflow(B3));
2169   EXPECT_ALWAYS_OVERFLOWS_HIGH(A.signedSubMayOverflow(B4));
2170 
2171   ConstantRange C(APInt(16, 0x8200), APInt(16, 0x8300));
2172   ConstantRange D1(APInt(16, 0x0100), APInt(16, 0x0201));
2173   ConstantRange D2(APInt(16, 0x0100), APInt(16, 0x0202));
2174   EXPECT_NEVER_OVERFLOWS(C.signedSubMayOverflow(D1));
2175   EXPECT_MAY_OVERFLOW(C.signedSubMayOverflow(D2));
2176   ConstantRange D3(APInt(16, 0x0299), APInt(16, 0x0400));
2177   ConstantRange D4(APInt(16, 0x0300), APInt(16, 0x0400));
2178   EXPECT_MAY_OVERFLOW(C.signedSubMayOverflow(D3));
2179   EXPECT_ALWAYS_OVERFLOWS_LOW(C.signedSubMayOverflow(D4));
2180 
2181   ConstantRange E(APInt(16, 0xff00), APInt(16, 0x0100));
2182   EXPECT_NEVER_OVERFLOWS(E.signedSubMayOverflow(E));
2183   ConstantRange F(APInt(16, 0xf000), APInt(16, 0x7001));
2184   EXPECT_MAY_OVERFLOW(F.signedSubMayOverflow(F));
2185 }
2186 
2187 template<typename Fn1, typename Fn2>
2188 static void TestOverflowExhaustive(Fn1 OverflowFn, Fn2 MayOverflowFn) {
2189   // Constant range overflow checks are tested exhaustively on 4-bit numbers.
2190   unsigned Bits = 4;
2191   EnumerateTwoConstantRanges(Bits, [=](const ConstantRange &CR1,
2192                                        const ConstantRange &CR2) {
2193     // Loop over all N1 in CR1 and N2 in CR2 and check whether any of the
2194     // operations have overflow / have no overflow.
2195     bool RangeHasOverflowLow = false;
2196     bool RangeHasOverflowHigh = false;
2197     bool RangeHasNoOverflow = false;
2198     ForeachNumInConstantRange(CR1, [&](const APInt &N1) {
2199       ForeachNumInConstantRange(CR2, [&](const APInt &N2) {
2200         bool IsOverflowHigh;
2201         if (!OverflowFn(IsOverflowHigh, N1, N2)) {
2202           RangeHasNoOverflow = true;
2203           return;
2204         }
2205 
2206         if (IsOverflowHigh)
2207           RangeHasOverflowHigh = true;
2208         else
2209           RangeHasOverflowLow = true;
2210       });
2211     });
2212 
2213     ConstantRange::OverflowResult OR = MayOverflowFn(CR1, CR2);
2214     switch (OR) {
2215     case ConstantRange::OverflowResult::AlwaysOverflowsLow:
2216       EXPECT_TRUE(RangeHasOverflowLow);
2217       EXPECT_FALSE(RangeHasOverflowHigh);
2218       EXPECT_FALSE(RangeHasNoOverflow);
2219       break;
2220     case ConstantRange::OverflowResult::AlwaysOverflowsHigh:
2221       EXPECT_TRUE(RangeHasOverflowHigh);
2222       EXPECT_FALSE(RangeHasOverflowLow);
2223       EXPECT_FALSE(RangeHasNoOverflow);
2224       break;
2225     case ConstantRange::OverflowResult::NeverOverflows:
2226       EXPECT_FALSE(RangeHasOverflowLow);
2227       EXPECT_FALSE(RangeHasOverflowHigh);
2228       EXPECT_TRUE(RangeHasNoOverflow);
2229       break;
2230     case ConstantRange::OverflowResult::MayOverflow:
2231       // We return MayOverflow for empty sets as a conservative result,
2232       // but of course neither the RangeHasOverflow nor the
2233       // RangeHasNoOverflow flags will be set.
2234       if (CR1.isEmptySet() || CR2.isEmptySet())
2235         break;
2236 
2237       EXPECT_TRUE(RangeHasOverflowLow || RangeHasOverflowHigh);
2238       EXPECT_TRUE(RangeHasNoOverflow);
2239       break;
2240     }
2241   });
2242 }
2243 
2244 TEST_F(ConstantRangeTest, UnsignedAddOverflowExhaustive) {
2245   TestOverflowExhaustive(
2246       [](bool &IsOverflowHigh, const APInt &N1, const APInt &N2) {
2247         bool Overflow;
2248         (void) N1.uadd_ov(N2, Overflow);
2249         IsOverflowHigh = true;
2250         return Overflow;
2251       },
2252       [](const ConstantRange &CR1, const ConstantRange &CR2) {
2253         return CR1.unsignedAddMayOverflow(CR2);
2254       });
2255 }
2256 
2257 TEST_F(ConstantRangeTest, UnsignedSubOverflowExhaustive) {
2258   TestOverflowExhaustive(
2259       [](bool &IsOverflowHigh, const APInt &N1, const APInt &N2) {
2260         bool Overflow;
2261         (void) N1.usub_ov(N2, Overflow);
2262         IsOverflowHigh = false;
2263         return Overflow;
2264       },
2265       [](const ConstantRange &CR1, const ConstantRange &CR2) {
2266         return CR1.unsignedSubMayOverflow(CR2);
2267       });
2268 }
2269 
2270 TEST_F(ConstantRangeTest, UnsignedMulOverflowExhaustive) {
2271   TestOverflowExhaustive(
2272       [](bool &IsOverflowHigh, const APInt &N1, const APInt &N2) {
2273         bool Overflow;
2274         (void) N1.umul_ov(N2, Overflow);
2275         IsOverflowHigh = true;
2276         return Overflow;
2277       },
2278       [](const ConstantRange &CR1, const ConstantRange &CR2) {
2279         return CR1.unsignedMulMayOverflow(CR2);
2280       });
2281 }
2282 
2283 TEST_F(ConstantRangeTest, SignedAddOverflowExhaustive) {
2284   TestOverflowExhaustive(
2285       [](bool &IsOverflowHigh, const APInt &N1, const APInt &N2) {
2286         bool Overflow;
2287         (void) N1.sadd_ov(N2, Overflow);
2288         IsOverflowHigh = N1.isNonNegative();
2289         return Overflow;
2290       },
2291       [](const ConstantRange &CR1, const ConstantRange &CR2) {
2292         return CR1.signedAddMayOverflow(CR2);
2293       });
2294 }
2295 
2296 TEST_F(ConstantRangeTest, SignedSubOverflowExhaustive) {
2297   TestOverflowExhaustive(
2298       [](bool &IsOverflowHigh, const APInt &N1, const APInt &N2) {
2299         bool Overflow;
2300         (void) N1.ssub_ov(N2, Overflow);
2301         IsOverflowHigh = N1.isNonNegative();
2302         return Overflow;
2303       },
2304       [](const ConstantRange &CR1, const ConstantRange &CR2) {
2305         return CR1.signedSubMayOverflow(CR2);
2306       });
2307 }
2308 
2309 TEST_F(ConstantRangeTest, FromKnownBits) {
2310   KnownBits Unknown(16);
2311   EXPECT_EQ(Full, ConstantRange::fromKnownBits(Unknown, /*signed*/false));
2312   EXPECT_EQ(Full, ConstantRange::fromKnownBits(Unknown, /*signed*/true));
2313 
2314   // .10..01. -> unsigned 01000010 (66)  to 11011011 (219)
2315   //          -> signed   11000010 (194) to 01011011 (91)
2316   KnownBits Known(8);
2317   Known.Zero = 36;
2318   Known.One = 66;
2319   ConstantRange Unsigned(APInt(8, 66), APInt(8, 219 + 1));
2320   ConstantRange Signed(APInt(8, 194), APInt(8, 91 + 1));
2321   EXPECT_EQ(Unsigned, ConstantRange::fromKnownBits(Known, /*signed*/false));
2322   EXPECT_EQ(Signed, ConstantRange::fromKnownBits(Known, /*signed*/true));
2323 
2324   // 1.10.10. -> 10100100 (164) to 11101101 (237)
2325   Known.Zero = 18;
2326   Known.One = 164;
2327   ConstantRange CR1(APInt(8, 164), APInt(8, 237 + 1));
2328   EXPECT_EQ(CR1, ConstantRange::fromKnownBits(Known, /*signed*/false));
2329   EXPECT_EQ(CR1, ConstantRange::fromKnownBits(Known, /*signed*/true));
2330 
2331   // 01.0.1.0 -> 01000100 (68) to 01101110 (110)
2332   Known.Zero = 145;
2333   Known.One = 68;
2334   ConstantRange CR2(APInt(8, 68), APInt(8, 110 + 1));
2335   EXPECT_EQ(CR2, ConstantRange::fromKnownBits(Known, /*signed*/false));
2336   EXPECT_EQ(CR2, ConstantRange::fromKnownBits(Known, /*signed*/true));
2337 }
2338 
2339 TEST_F(ConstantRangeTest, FromKnownBitsExhaustive) {
2340   unsigned Bits = 4;
2341   unsigned Max = 1 << Bits;
2342   KnownBits Known(Bits);
2343   for (unsigned Zero = 0; Zero < Max; ++Zero) {
2344     for (unsigned One = 0; One < Max; ++One) {
2345       Known.Zero = Zero;
2346       Known.One = One;
2347       if (Known.hasConflict() || Known.isUnknown())
2348         continue;
2349 
2350       UnsignedOpRangeGatherer UR(Bits);
2351       SignedOpRangeGatherer SR(Bits);
2352       for (unsigned N = 0; N < Max; ++N) {
2353         APInt Num(Bits, N);
2354         if ((Num & Known.Zero) != 0 || (~Num & Known.One) != 0)
2355           continue;
2356 
2357         UR.account(Num);
2358         SR.account(Num);
2359       }
2360 
2361       ConstantRange UnsignedCR = UR.getRange();
2362       ConstantRange SignedCR = SR.getRange();
2363       EXPECT_EQ(UnsignedCR, ConstantRange::fromKnownBits(Known, false));
2364       EXPECT_EQ(SignedCR, ConstantRange::fromKnownBits(Known, true));
2365     }
2366   }
2367 }
2368 
2369 TEST_F(ConstantRangeTest, ToKnownBits) {
2370   unsigned Bits = 4;
2371   EnumerateConstantRanges(Bits, [&](const ConstantRange &CR) {
2372     KnownBits Known = CR.toKnownBits();
2373     KnownBits ExpectedKnown(Bits);
2374     ExpectedKnown.Zero.setAllBits();
2375     ExpectedKnown.One.setAllBits();
2376     ForeachNumInConstantRange(CR, [&](const APInt &N) {
2377       ExpectedKnown.One &= N;
2378       ExpectedKnown.Zero &= ~N;
2379     });
2380     // For an empty CR any result would be legal.
2381     if (!CR.isEmptySet()) {
2382       EXPECT_EQ(ExpectedKnown, Known);
2383     }
2384   });
2385 }
2386 
2387 TEST_F(ConstantRangeTest, Negative) {
2388   // All elements in an empty set (of which there are none) are both negative
2389   // and non-negative. Empty & full sets checked explicitly for clarity, but
2390   // they are also covered by the exhaustive test below.
2391   EXPECT_TRUE(Empty.isAllNegative());
2392   EXPECT_TRUE(Empty.isAllNonNegative());
2393   EXPECT_FALSE(Full.isAllNegative());
2394   EXPECT_FALSE(Full.isAllNonNegative());
2395 
2396   unsigned Bits = 4;
2397   EnumerateConstantRanges(Bits, [](const ConstantRange &CR) {
2398     bool AllNegative = true;
2399     bool AllNonNegative = true;
2400     ForeachNumInConstantRange(CR, [&](const APInt &N) {
2401       if (!N.isNegative())
2402         AllNegative = false;
2403       if (!N.isNonNegative())
2404         AllNonNegative = false;
2405     });
2406     assert((CR.isEmptySet() || !AllNegative || !AllNonNegative) &&
2407            "Only empty set can be both all negative and all non-negative");
2408 
2409     EXPECT_EQ(AllNegative, CR.isAllNegative());
2410     EXPECT_EQ(AllNonNegative, CR.isAllNonNegative());
2411   });
2412 }
2413 
2414 TEST_F(ConstantRangeTest, UAddSat) {
2415   TestBinaryOpExhaustive(
2416       [](const ConstantRange &CR1, const ConstantRange &CR2) {
2417         return CR1.uadd_sat(CR2);
2418       },
2419       [](const APInt &N1, const APInt &N2) {
2420         return N1.uadd_sat(N2);
2421       },
2422       PreferSmallestUnsigned);
2423 }
2424 
2425 TEST_F(ConstantRangeTest, USubSat) {
2426   TestBinaryOpExhaustive(
2427       [](const ConstantRange &CR1, const ConstantRange &CR2) {
2428         return CR1.usub_sat(CR2);
2429       },
2430       [](const APInt &N1, const APInt &N2) {
2431         return N1.usub_sat(N2);
2432       },
2433       PreferSmallestUnsigned);
2434 }
2435 
2436 TEST_F(ConstantRangeTest, UMulSat) {
2437   TestBinaryOpExhaustive(
2438       [](const ConstantRange &CR1, const ConstantRange &CR2) {
2439         return CR1.umul_sat(CR2);
2440       },
2441       [](const APInt &N1, const APInt &N2) { return N1.umul_sat(N2); },
2442       PreferSmallestUnsigned);
2443 }
2444 
2445 TEST_F(ConstantRangeTest, UShlSat) {
2446   TestBinaryOpExhaustive(
2447       [](const ConstantRange &CR1, const ConstantRange &CR2) {
2448         return CR1.ushl_sat(CR2);
2449       },
2450       [](const APInt &N1, const APInt &N2) { return N1.ushl_sat(N2); },
2451       PreferSmallestUnsigned);
2452 }
2453 
2454 TEST_F(ConstantRangeTest, SAddSat) {
2455   TestBinaryOpExhaustive(
2456       [](const ConstantRange &CR1, const ConstantRange &CR2) {
2457         return CR1.sadd_sat(CR2);
2458       },
2459       [](const APInt &N1, const APInt &N2) {
2460         return N1.sadd_sat(N2);
2461       },
2462       PreferSmallestSigned);
2463 }
2464 
2465 TEST_F(ConstantRangeTest, SSubSat) {
2466   TestBinaryOpExhaustive(
2467       [](const ConstantRange &CR1, const ConstantRange &CR2) {
2468         return CR1.ssub_sat(CR2);
2469       },
2470       [](const APInt &N1, const APInt &N2) {
2471         return N1.ssub_sat(N2);
2472       },
2473       PreferSmallestSigned);
2474 }
2475 
2476 TEST_F(ConstantRangeTest, SMulSat) {
2477   TestBinaryOpExhaustive(
2478       [](const ConstantRange &CR1, const ConstantRange &CR2) {
2479         return CR1.smul_sat(CR2);
2480       },
2481       [](const APInt &N1, const APInt &N2) { return N1.smul_sat(N2); },
2482       PreferSmallestSigned);
2483 }
2484 
2485 TEST_F(ConstantRangeTest, SShlSat) {
2486   TestBinaryOpExhaustive(
2487       [](const ConstantRange &CR1, const ConstantRange &CR2) {
2488         return CR1.sshl_sat(CR2);
2489       },
2490       [](const APInt &N1, const APInt &N2) { return N1.sshl_sat(N2); },
2491       PreferSmallestSigned);
2492 }
2493 
2494 TEST_F(ConstantRangeTest, Abs) {
2495   TestUnaryOpExhaustive(
2496       [](const ConstantRange &CR) { return CR.abs(); },
2497       [](const APInt &N) { return N.abs(); });
2498 
2499   TestUnaryOpExhaustive(
2500       [](const ConstantRange &CR) { return CR.abs(/*IntMinIsPoison=*/true); },
2501       [](const APInt &N) -> Optional<APInt> {
2502         if (N.isMinSignedValue())
2503           return None;
2504         return N.abs();
2505       });
2506 }
2507 
2508 TEST_F(ConstantRangeTest, castOps) {
2509   ConstantRange A(APInt(16, 66), APInt(16, 128));
2510   ConstantRange FpToI8 = A.castOp(Instruction::FPToSI, 8);
2511   EXPECT_EQ(8u, FpToI8.getBitWidth());
2512   EXPECT_TRUE(FpToI8.isFullSet());
2513 
2514   ConstantRange FpToI16 = A.castOp(Instruction::FPToSI, 16);
2515   EXPECT_EQ(16u, FpToI16.getBitWidth());
2516   EXPECT_EQ(A, FpToI16);
2517 
2518   ConstantRange FPExtToDouble = A.castOp(Instruction::FPExt, 64);
2519   EXPECT_EQ(64u, FPExtToDouble.getBitWidth());
2520   EXPECT_TRUE(FPExtToDouble.isFullSet());
2521 
2522   ConstantRange PtrToInt = A.castOp(Instruction::PtrToInt, 64);
2523   EXPECT_EQ(64u, PtrToInt.getBitWidth());
2524   EXPECT_TRUE(PtrToInt.isFullSet());
2525 
2526   ConstantRange IntToPtr = A.castOp(Instruction::IntToPtr, 64);
2527   EXPECT_EQ(64u, IntToPtr.getBitWidth());
2528   EXPECT_TRUE(IntToPtr.isFullSet());
2529 }
2530 
2531 TEST_F(ConstantRangeTest, binaryAnd) {
2532   // Single element ranges.
2533   ConstantRange R16(APInt(8, 16));
2534   ConstantRange R20(APInt(8, 20));
2535   EXPECT_EQ(*R16.binaryAnd(R16).getSingleElement(), APInt(8, 16));
2536   EXPECT_EQ(*R16.binaryAnd(R20).getSingleElement(), APInt(8, 16 & 20));
2537 
2538   ConstantRange R16_32(APInt(8, 16), APInt(8, 32));
2539   // 'And' with a high bits mask.
2540   ConstantRange R32(APInt(8, 32));
2541   EXPECT_TRUE(R16_32.binaryAnd(R32).getSingleElement()->isZero());
2542   EXPECT_TRUE(R32.binaryAnd(R16_32).getSingleElement()->isZero());
2543   // 'And' with a low bits mask. Handled conservatively for now.
2544   ConstantRange R4(APInt(8, 4));
2545   ConstantRange R0_5(APInt(8, 0), APInt(8, 5));
2546   EXPECT_EQ(R16_32.binaryAnd(R4), R0_5);
2547   EXPECT_EQ(R4.binaryAnd(R16_32), R0_5);
2548 
2549   // Ranges with more than one element. Handled conservatively for now.
2550   ConstantRange R0_99(APInt(8, 0), APInt(8, 99));
2551   ConstantRange R0_32(APInt(8, 0), APInt(8, 32));
2552   EXPECT_EQ(R16_32.binaryAnd(R0_99), R0_32);
2553   EXPECT_EQ(R0_99.binaryAnd(R16_32), R0_32);
2554 
2555   TestBinaryOpExhaustive(
2556       [](const ConstantRange &CR1, const ConstantRange &CR2) {
2557         return CR1.binaryAnd(CR2);
2558       },
2559       [](const APInt &N1, const APInt &N2) { return N1 & N2; }, PreferSmallest,
2560       CheckSingleElementsOnly);
2561 }
2562 
2563 TEST_F(ConstantRangeTest, binaryOr) {
2564   // Single element ranges.
2565   ConstantRange R16(APInt(8, 16));
2566   ConstantRange R20(APInt(8, 20));
2567   EXPECT_EQ(*R16.binaryOr(R16).getSingleElement(), APInt(8, 16));
2568   EXPECT_EQ(*R16.binaryOr(R20).getSingleElement(), APInt(8, 16 | 20));
2569 
2570   ConstantRange R16_32(APInt(8, 16), APInt(8, 32));
2571   // 'Or' with a high bits mask.
2572   // KnownBits estimate is important, otherwise the maximum included element
2573   // would be 2^8 - 1.
2574   ConstantRange R32(APInt(8, 32));
2575   ConstantRange R48_64(APInt(8, 48), APInt(8, 64));
2576   EXPECT_EQ(R16_32.binaryOr(R32), R48_64);
2577   EXPECT_EQ(R32.binaryOr(R16_32), R48_64);
2578   // 'Or' with a low bits mask.
2579   ConstantRange R4(APInt(8, 4));
2580   ConstantRange R0_16(APInt(8, 0), APInt(8, 16));
2581   ConstantRange R4_16(APInt(8, 4), APInt(8, 16));
2582   EXPECT_EQ(R0_16.binaryOr(R4), R4_16);
2583   EXPECT_EQ(R4.binaryOr(R0_16), R4_16);
2584 
2585   // Ranges with more than one element. Handled conservatively for now.
2586   // UMaxUMin estimate is important, otherwise the lower bound would be zero.
2587   ConstantRange R0_64(APInt(8, 0), APInt(8, 64));
2588   ConstantRange R5_32(APInt(8, 5), APInt(8, 32));
2589   ConstantRange R5_64(APInt(8, 5), APInt(8, 64));
2590   EXPECT_EQ(R0_64.binaryOr(R5_32), R5_64);
2591   EXPECT_EQ(R5_32.binaryOr(R0_64), R5_64);
2592 
2593   TestBinaryOpExhaustive(
2594       [](const ConstantRange &CR1, const ConstantRange &CR2) {
2595         return CR1.binaryOr(CR2);
2596       },
2597       [](const APInt &N1, const APInt &N2) { return N1 | N2; }, PreferSmallest,
2598       CheckSingleElementsOnly);
2599 }
2600 
2601 TEST_F(ConstantRangeTest, binaryXor) {
2602   // Single element ranges.
2603   ConstantRange R16(APInt(8, 16));
2604   ConstantRange R20(APInt(8, 20));
2605   EXPECT_EQ(*R16.binaryXor(R16).getSingleElement(), APInt(8, 0));
2606   EXPECT_EQ(*R16.binaryXor(R20).getSingleElement(), APInt(8, 16 ^ 20));
2607 
2608   // Ranges with more than a single element.
2609   ConstantRange R16_35(APInt(8, 16), APInt(8, 35));
2610   ConstantRange R0_99(APInt(8, 0), APInt(8, 99));
2611   EXPECT_EQ(R16_35.binaryXor(R16_35), ConstantRange(APInt(8, 0), APInt(8, 64)));
2612   EXPECT_EQ(R16_35.binaryXor(R0_99), ConstantRange(APInt(8, 0), APInt(8, 128)));
2613   EXPECT_EQ(R0_99.binaryXor(R16_35), ConstantRange(APInt(8, 0), APInt(8, 128)));
2614 
2615   TestBinaryOpExhaustive(
2616       [](const ConstantRange &CR1, const ConstantRange &CR2) {
2617         return CR1.binaryXor(CR2);
2618       },
2619       [](const APInt &N1, const APInt &N2) {
2620         return N1 ^ N2;
2621       },
2622       PreferSmallest,
2623       CheckSingleElementsOnly);
2624 }
2625 
2626 TEST_F(ConstantRangeTest, binaryNot) {
2627   TestUnaryOpExhaustive(
2628       [](const ConstantRange &CR) { return CR.binaryNot(); },
2629       [](const APInt &N) { return ~N; },
2630       PreferSmallest);
2631   TestUnaryOpExhaustive(
2632       [](const ConstantRange &CR) {
2633         return CR.binaryXor(ConstantRange(APInt::getAllOnes(CR.getBitWidth())));
2634       },
2635       [](const APInt &N) { return ~N; }, PreferSmallest);
2636   TestUnaryOpExhaustive(
2637       [](const ConstantRange &CR) {
2638         return ConstantRange(APInt::getAllOnes(CR.getBitWidth())).binaryXor(CR);
2639       },
2640       [](const APInt &N) { return ~N; }, PreferSmallest);
2641 }
2642 
2643 template <typename T>
2644 void testConstantRangeICmpPredEquivalence(ICmpInst::Predicate SrcPred, T Func) {
2645   unsigned Bits = 4;
2646   EnumerateTwoConstantRanges(
2647       Bits, [&](const ConstantRange &CR1, const ConstantRange &CR2) {
2648         ICmpInst::Predicate TgtPred;
2649         bool ExpectedEquivalent;
2650         std::tie(TgtPred, ExpectedEquivalent) = Func(CR1, CR2);
2651         if (TgtPred == CmpInst::Predicate::BAD_ICMP_PREDICATE)
2652           return;
2653         bool TrulyEquivalent = true;
2654         ForeachNumInConstantRange(CR1, [&](const APInt &N1) {
2655           if (!TrulyEquivalent)
2656             return;
2657           ForeachNumInConstantRange(CR2, [&](const APInt &N2) {
2658             if (!TrulyEquivalent)
2659               return;
2660             TrulyEquivalent &= ICmpInst::compare(N1, N2, SrcPred) ==
2661                                ICmpInst::compare(N1, N2, TgtPred);
2662           });
2663         });
2664         ASSERT_EQ(TrulyEquivalent, ExpectedEquivalent);
2665       });
2666 }
2667 
2668 TEST_F(ConstantRangeTest, areInsensitiveToSignednessOfICmpPredicate) {
2669   for (auto Pred : ICmpInst::predicates()) {
2670     if (ICmpInst::isEquality(Pred))
2671       continue;
2672     ICmpInst::Predicate FlippedSignednessPred =
2673         ICmpInst::getFlippedSignednessPredicate(Pred);
2674     testConstantRangeICmpPredEquivalence(Pred, [FlippedSignednessPred](
2675                                                    const ConstantRange &CR1,
2676                                                    const ConstantRange &CR2) {
2677       return std::make_pair(
2678           FlippedSignednessPred,
2679           ConstantRange::areInsensitiveToSignednessOfICmpPredicate(CR1, CR2));
2680     });
2681   }
2682 }
2683 
2684 TEST_F(ConstantRangeTest, areInsensitiveToSignednessOfInvertedICmpPredicate) {
2685   for (auto Pred : ICmpInst::predicates()) {
2686     if (ICmpInst::isEquality(Pred))
2687       continue;
2688     ICmpInst::Predicate InvertedFlippedSignednessPred =
2689         ICmpInst::getInversePredicate(
2690             ICmpInst::getFlippedSignednessPredicate(Pred));
2691     testConstantRangeICmpPredEquivalence(
2692         Pred, [InvertedFlippedSignednessPred](const ConstantRange &CR1,
2693                                               const ConstantRange &CR2) {
2694           return std::make_pair(
2695               InvertedFlippedSignednessPred,
2696               ConstantRange::areInsensitiveToSignednessOfInvertedICmpPredicate(
2697                   CR1, CR2));
2698         });
2699   }
2700 }
2701 
2702 TEST_F(ConstantRangeTest, getEquivalentPredWithFlippedSignedness) {
2703   for (auto Pred : ICmpInst::predicates()) {
2704     if (ICmpInst::isEquality(Pred))
2705       continue;
2706     testConstantRangeICmpPredEquivalence(
2707         Pred, [Pred](const ConstantRange &CR1, const ConstantRange &CR2) {
2708           return std::make_pair(
2709               ConstantRange::getEquivalentPredWithFlippedSignedness(Pred, CR1,
2710                                                                     CR2),
2711               /*ExpectedEquivalent=*/true);
2712         });
2713   }
2714 }
2715 
2716 TEST_F(ConstantRangeTest, isSizeLargerThan) {
2717   EXPECT_FALSE(Empty.isSizeLargerThan(0));
2718 
2719   EXPECT_TRUE(Full.isSizeLargerThan(0));
2720   EXPECT_TRUE(Full.isSizeLargerThan(65535));
2721   EXPECT_FALSE(Full.isSizeLargerThan(65536));
2722 
2723   EXPECT_TRUE(One.isSizeLargerThan(0));
2724   EXPECT_FALSE(One.isSizeLargerThan(1));
2725 }
2726 
2727 } // anonymous namespace
2728