xref: /llvm-project/llvm/unittests/IR/ConstantRangeTest.cpp (revision 89fae41ef142892d8d6c20ead28465a34e12172b)
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 static bool CheckNonWrappedOnly(const ConstantRange &CR1,
210                                 const ConstantRange &CR2) {
211   return !CR1.isWrappedSet() && !CR2.isWrappedSet();
212 }
213 
214 static bool CheckNonSignWrappedOnly(const ConstantRange &CR1,
215                                     const ConstantRange &CR2) {
216   return !CR1.isSignWrappedSet() && !CR2.isSignWrappedSet();
217 }
218 
219 static bool CheckNonWrappedOrSignWrappedOnly(const ConstantRange &CR1,
220                                              const ConstantRange &CR2) {
221   return !CR1.isWrappedSet() && !CR1.isSignWrappedSet() &&
222          !CR2.isWrappedSet() && !CR2.isSignWrappedSet();
223 }
224 
225 // CheckFn determines whether optimality is checked for a given range pair.
226 // Correctness is always checked.
227 static void TestBinaryOpExhaustive(BinaryRangeFn RangeFn, BinaryIntFn IntFn,
228                                    PreferFn PreferenceFn = PreferSmallest,
229                                    BinaryCheckFn CheckFn = CheckAll) {
230   unsigned Bits = 4;
231   EnumerateTwoConstantRanges(
232       Bits, [&](const ConstantRange &CR1, const ConstantRange &CR2) {
233         SmallBitVector Elems(1 << Bits);
234         ForeachNumInConstantRange(CR1, [&](const APInt &N1) {
235           ForeachNumInConstantRange(CR2, [&](const APInt &N2) {
236             if (Optional<APInt> ResultN = IntFn(N1, N2))
237               Elems.set(ResultN->getZExtValue());
238           });
239         });
240         TestRange(RangeFn(CR1, CR2), Elems, PreferenceFn, {CR1, CR2},
241                   CheckFn(CR1, CR2));
242       });
243 }
244 
245 ConstantRange ConstantRangeTest::Full(16, true);
246 ConstantRange ConstantRangeTest::Empty(16, false);
247 ConstantRange ConstantRangeTest::One(APInt(16, 0xa));
248 ConstantRange ConstantRangeTest::Some(APInt(16, 0xa), APInt(16, 0xaaa));
249 ConstantRange ConstantRangeTest::Wrap(APInt(16, 0xaaa), APInt(16, 0xa));
250 
251 TEST_F(ConstantRangeTest, Basics) {
252   EXPECT_TRUE(Full.isFullSet());
253   EXPECT_FALSE(Full.isEmptySet());
254   EXPECT_TRUE(Full.inverse().isEmptySet());
255   EXPECT_FALSE(Full.isWrappedSet());
256   EXPECT_TRUE(Full.contains(APInt(16, 0x0)));
257   EXPECT_TRUE(Full.contains(APInt(16, 0x9)));
258   EXPECT_TRUE(Full.contains(APInt(16, 0xa)));
259   EXPECT_TRUE(Full.contains(APInt(16, 0xaa9)));
260   EXPECT_TRUE(Full.contains(APInt(16, 0xaaa)));
261 
262   EXPECT_FALSE(Empty.isFullSet());
263   EXPECT_TRUE(Empty.isEmptySet());
264   EXPECT_TRUE(Empty.inverse().isFullSet());
265   EXPECT_FALSE(Empty.isWrappedSet());
266   EXPECT_FALSE(Empty.contains(APInt(16, 0x0)));
267   EXPECT_FALSE(Empty.contains(APInt(16, 0x9)));
268   EXPECT_FALSE(Empty.contains(APInt(16, 0xa)));
269   EXPECT_FALSE(Empty.contains(APInt(16, 0xaa9)));
270   EXPECT_FALSE(Empty.contains(APInt(16, 0xaaa)));
271 
272   EXPECT_FALSE(One.isFullSet());
273   EXPECT_FALSE(One.isEmptySet());
274   EXPECT_FALSE(One.isWrappedSet());
275   EXPECT_FALSE(One.contains(APInt(16, 0x0)));
276   EXPECT_FALSE(One.contains(APInt(16, 0x9)));
277   EXPECT_TRUE(One.contains(APInt(16, 0xa)));
278   EXPECT_FALSE(One.contains(APInt(16, 0xaa9)));
279   EXPECT_FALSE(One.contains(APInt(16, 0xaaa)));
280   EXPECT_FALSE(One.inverse().contains(APInt(16, 0xa)));
281 
282   EXPECT_FALSE(Some.isFullSet());
283   EXPECT_FALSE(Some.isEmptySet());
284   EXPECT_FALSE(Some.isWrappedSet());
285   EXPECT_FALSE(Some.contains(APInt(16, 0x0)));
286   EXPECT_FALSE(Some.contains(APInt(16, 0x9)));
287   EXPECT_TRUE(Some.contains(APInt(16, 0xa)));
288   EXPECT_TRUE(Some.contains(APInt(16, 0xaa9)));
289   EXPECT_FALSE(Some.contains(APInt(16, 0xaaa)));
290 
291   EXPECT_FALSE(Wrap.isFullSet());
292   EXPECT_FALSE(Wrap.isEmptySet());
293   EXPECT_TRUE(Wrap.isWrappedSet());
294   EXPECT_TRUE(Wrap.contains(APInt(16, 0x0)));
295   EXPECT_TRUE(Wrap.contains(APInt(16, 0x9)));
296   EXPECT_FALSE(Wrap.contains(APInt(16, 0xa)));
297   EXPECT_FALSE(Wrap.contains(APInt(16, 0xaa9)));
298   EXPECT_TRUE(Wrap.contains(APInt(16, 0xaaa)));
299 }
300 
301 TEST_F(ConstantRangeTest, Equality) {
302   EXPECT_EQ(Full, Full);
303   EXPECT_EQ(Empty, Empty);
304   EXPECT_EQ(One, One);
305   EXPECT_EQ(Some, Some);
306   EXPECT_EQ(Wrap, Wrap);
307   EXPECT_NE(Full, Empty);
308   EXPECT_NE(Full, One);
309   EXPECT_NE(Full, Some);
310   EXPECT_NE(Full, Wrap);
311   EXPECT_NE(Empty, One);
312   EXPECT_NE(Empty, Some);
313   EXPECT_NE(Empty, Wrap);
314   EXPECT_NE(One, Some);
315   EXPECT_NE(One, Wrap);
316   EXPECT_NE(Some, Wrap);
317 }
318 
319 TEST_F(ConstantRangeTest, SingleElement) {
320   EXPECT_EQ(Full.getSingleElement(), static_cast<APInt *>(nullptr));
321   EXPECT_EQ(Empty.getSingleElement(), static_cast<APInt *>(nullptr));
322   EXPECT_EQ(Full.getSingleMissingElement(), static_cast<APInt *>(nullptr));
323   EXPECT_EQ(Empty.getSingleMissingElement(), static_cast<APInt *>(nullptr));
324 
325   EXPECT_EQ(*One.getSingleElement(), APInt(16, 0xa));
326   EXPECT_EQ(Some.getSingleElement(), static_cast<APInt *>(nullptr));
327   EXPECT_EQ(Wrap.getSingleElement(), static_cast<APInt *>(nullptr));
328 
329   EXPECT_EQ(One.getSingleMissingElement(), static_cast<APInt *>(nullptr));
330   EXPECT_EQ(Some.getSingleMissingElement(), static_cast<APInt *>(nullptr));
331 
332   ConstantRange OneInverse = One.inverse();
333   EXPECT_EQ(*OneInverse.getSingleMissingElement(), *One.getSingleElement());
334 
335   EXPECT_FALSE(Full.isSingleElement());
336   EXPECT_FALSE(Empty.isSingleElement());
337   EXPECT_TRUE(One.isSingleElement());
338   EXPECT_FALSE(Some.isSingleElement());
339   EXPECT_FALSE(Wrap.isSingleElement());
340 }
341 
342 TEST_F(ConstantRangeTest, GetMinsAndMaxes) {
343   EXPECT_EQ(Full.getUnsignedMax(), APInt(16, UINT16_MAX));
344   EXPECT_EQ(One.getUnsignedMax(), APInt(16, 0xa));
345   EXPECT_EQ(Some.getUnsignedMax(), APInt(16, 0xaa9));
346   EXPECT_EQ(Wrap.getUnsignedMax(), APInt(16, UINT16_MAX));
347 
348   EXPECT_EQ(Full.getUnsignedMin(), APInt(16, 0));
349   EXPECT_EQ(One.getUnsignedMin(), APInt(16, 0xa));
350   EXPECT_EQ(Some.getUnsignedMin(), APInt(16, 0xa));
351   EXPECT_EQ(Wrap.getUnsignedMin(), APInt(16, 0));
352 
353   EXPECT_EQ(Full.getSignedMax(), APInt(16, INT16_MAX));
354   EXPECT_EQ(One.getSignedMax(), APInt(16, 0xa));
355   EXPECT_EQ(Some.getSignedMax(), APInt(16, 0xaa9));
356   EXPECT_EQ(Wrap.getSignedMax(), APInt(16, INT16_MAX));
357 
358   EXPECT_EQ(Full.getSignedMin(), APInt(16, (uint64_t)INT16_MIN));
359   EXPECT_EQ(One.getSignedMin(), APInt(16, 0xa));
360   EXPECT_EQ(Some.getSignedMin(), APInt(16, 0xa));
361   EXPECT_EQ(Wrap.getSignedMin(), APInt(16, (uint64_t)INT16_MIN));
362 
363   // Found by Klee
364   EXPECT_EQ(ConstantRange(APInt(4, 7), APInt(4, 0)).getSignedMax(),
365             APInt(4, 7));
366 }
367 
368 TEST_F(ConstantRangeTest, SignWrapped) {
369   EXPECT_FALSE(Full.isSignWrappedSet());
370   EXPECT_FALSE(Empty.isSignWrappedSet());
371   EXPECT_FALSE(One.isSignWrappedSet());
372   EXPECT_FALSE(Some.isSignWrappedSet());
373   EXPECT_TRUE(Wrap.isSignWrappedSet());
374 
375   EXPECT_FALSE(ConstantRange(APInt(8, 127), APInt(8, 128)).isSignWrappedSet());
376   EXPECT_TRUE(ConstantRange(APInt(8, 127), APInt(8, 129)).isSignWrappedSet());
377   EXPECT_FALSE(ConstantRange(APInt(8, 128), APInt(8, 129)).isSignWrappedSet());
378   EXPECT_TRUE(ConstantRange(APInt(8, 10), APInt(8, 9)).isSignWrappedSet());
379   EXPECT_TRUE(ConstantRange(APInt(8, 10), APInt(8, 250)).isSignWrappedSet());
380   EXPECT_FALSE(ConstantRange(APInt(8, 250), APInt(8, 10)).isSignWrappedSet());
381   EXPECT_FALSE(ConstantRange(APInt(8, 250), APInt(8, 251)).isSignWrappedSet());
382 }
383 
384 TEST_F(ConstantRangeTest, UpperWrapped) {
385   // The behavior here is the same as for isWrappedSet() / isSignWrappedSet().
386   EXPECT_FALSE(Full.isUpperWrapped());
387   EXPECT_FALSE(Empty.isUpperWrapped());
388   EXPECT_FALSE(One.isUpperWrapped());
389   EXPECT_FALSE(Some.isUpperWrapped());
390   EXPECT_TRUE(Wrap.isUpperWrapped());
391   EXPECT_FALSE(Full.isUpperSignWrapped());
392   EXPECT_FALSE(Empty.isUpperSignWrapped());
393   EXPECT_FALSE(One.isUpperSignWrapped());
394   EXPECT_FALSE(Some.isUpperSignWrapped());
395   EXPECT_TRUE(Wrap.isUpperSignWrapped());
396 
397   // The behavior differs if Upper is the Min/SignedMin value.
398   ConstantRange CR1(APInt(8, 42), APInt::getMinValue(8));
399   EXPECT_FALSE(CR1.isWrappedSet());
400   EXPECT_TRUE(CR1.isUpperWrapped());
401 
402   ConstantRange CR2(APInt(8, 42), APInt::getSignedMinValue(8));
403   EXPECT_FALSE(CR2.isSignWrappedSet());
404   EXPECT_TRUE(CR2.isUpperSignWrapped());
405 }
406 
407 TEST_F(ConstantRangeTest, Trunc) {
408   ConstantRange TFull = Full.truncate(10);
409   ConstantRange TEmpty = Empty.truncate(10);
410   ConstantRange TOne = One.truncate(10);
411   ConstantRange TSome = Some.truncate(10);
412   ConstantRange TWrap = Wrap.truncate(10);
413   EXPECT_TRUE(TFull.isFullSet());
414   EXPECT_TRUE(TEmpty.isEmptySet());
415   EXPECT_EQ(TOne, ConstantRange(One.getLower().trunc(10),
416                                 One.getUpper().trunc(10)));
417   EXPECT_TRUE(TSome.isFullSet());
418   EXPECT_TRUE(TWrap.isFullSet());
419 
420   // trunc([2, 5), 3->2) = [2, 1)
421   ConstantRange TwoFive(APInt(3, 2), APInt(3, 5));
422   EXPECT_EQ(TwoFive.truncate(2), ConstantRange(APInt(2, 2), APInt(2, 1)));
423 
424   // trunc([2, 6), 3->2) = full
425   ConstantRange TwoSix(APInt(3, 2), APInt(3, 6));
426   EXPECT_TRUE(TwoSix.truncate(2).isFullSet());
427 
428   // trunc([5, 7), 3->2) = [1, 3)
429   ConstantRange FiveSeven(APInt(3, 5), APInt(3, 7));
430   EXPECT_EQ(FiveSeven.truncate(2), ConstantRange(APInt(2, 1), APInt(2, 3)));
431 
432   // trunc([7, 1), 3->2) = [3, 1)
433   ConstantRange SevenOne(APInt(3, 7), APInt(3, 1));
434   EXPECT_EQ(SevenOne.truncate(2), ConstantRange(APInt(2, 3), APInt(2, 1)));
435 }
436 
437 TEST_F(ConstantRangeTest, ZExt) {
438   ConstantRange ZFull = Full.zeroExtend(20);
439   ConstantRange ZEmpty = Empty.zeroExtend(20);
440   ConstantRange ZOne = One.zeroExtend(20);
441   ConstantRange ZSome = Some.zeroExtend(20);
442   ConstantRange ZWrap = Wrap.zeroExtend(20);
443   EXPECT_EQ(ZFull, ConstantRange(APInt(20, 0), APInt(20, 0x10000)));
444   EXPECT_TRUE(ZEmpty.isEmptySet());
445   EXPECT_EQ(ZOne, ConstantRange(One.getLower().zext(20),
446                                 One.getUpper().zext(20)));
447   EXPECT_EQ(ZSome, ConstantRange(Some.getLower().zext(20),
448                                  Some.getUpper().zext(20)));
449   EXPECT_EQ(ZWrap, ConstantRange(APInt(20, 0), APInt(20, 0x10000)));
450 
451   // zext([5, 0), 3->7) = [5, 8)
452   ConstantRange FiveZero(APInt(3, 5), APInt(3, 0));
453   EXPECT_EQ(FiveZero.zeroExtend(7), ConstantRange(APInt(7, 5), APInt(7, 8)));
454 }
455 
456 TEST_F(ConstantRangeTest, SExt) {
457   ConstantRange SFull = Full.signExtend(20);
458   ConstantRange SEmpty = Empty.signExtend(20);
459   ConstantRange SOne = One.signExtend(20);
460   ConstantRange SSome = Some.signExtend(20);
461   ConstantRange SWrap = Wrap.signExtend(20);
462   EXPECT_EQ(SFull, ConstantRange(APInt(20, (uint64_t)INT16_MIN, true),
463                                  APInt(20, INT16_MAX + 1, true)));
464   EXPECT_TRUE(SEmpty.isEmptySet());
465   EXPECT_EQ(SOne, ConstantRange(One.getLower().sext(20),
466                                 One.getUpper().sext(20)));
467   EXPECT_EQ(SSome, ConstantRange(Some.getLower().sext(20),
468                                  Some.getUpper().sext(20)));
469   EXPECT_EQ(SWrap, ConstantRange(APInt(20, (uint64_t)INT16_MIN, true),
470                                  APInt(20, INT16_MAX + 1, true)));
471 
472   EXPECT_EQ(ConstantRange(APInt(8, 120), APInt(8, 140)).signExtend(16),
473             ConstantRange(APInt(16, -128), APInt(16, 128)));
474 
475   EXPECT_EQ(ConstantRange(APInt(16, 0x0200), APInt(16, 0x8000)).signExtend(19),
476             ConstantRange(APInt(19, 0x0200), APInt(19, 0x8000)));
477 }
478 
479 TEST_F(ConstantRangeTest, IntersectWith) {
480   EXPECT_EQ(Empty.intersectWith(Full), Empty);
481   EXPECT_EQ(Empty.intersectWith(Empty), Empty);
482   EXPECT_EQ(Empty.intersectWith(One), Empty);
483   EXPECT_EQ(Empty.intersectWith(Some), Empty);
484   EXPECT_EQ(Empty.intersectWith(Wrap), Empty);
485   EXPECT_EQ(Full.intersectWith(Full), Full);
486   EXPECT_EQ(Some.intersectWith(Some), Some);
487   EXPECT_EQ(Some.intersectWith(One), One);
488   EXPECT_EQ(Full.intersectWith(One), One);
489   EXPECT_EQ(Full.intersectWith(Some), Some);
490   EXPECT_EQ(Some.intersectWith(Wrap), Empty);
491   EXPECT_EQ(One.intersectWith(Wrap), Empty);
492   EXPECT_EQ(One.intersectWith(Wrap), Wrap.intersectWith(One));
493 
494   // Klee generated testcase from PR4545.
495   // The intersection of i16 [4, 2) and [6, 5) is disjoint, looking like
496   // 01..4.6789ABCDEF where the dots represent values not in the intersection.
497   ConstantRange LHS(APInt(16, 4), APInt(16, 2));
498   ConstantRange RHS(APInt(16, 6), APInt(16, 5));
499   EXPECT_TRUE(LHS.intersectWith(RHS) == LHS);
500 
501   // previous bug: intersection of [min, 3) and [2, max) should be 2
502   LHS = ConstantRange(APInt(32, -2147483646), APInt(32, 3));
503   RHS = ConstantRange(APInt(32, 2), APInt(32, 2147483646));
504   EXPECT_EQ(LHS.intersectWith(RHS), ConstantRange(APInt(32, 2)));
505 
506   // [2, 0) /\ [4, 3) = [2, 0)
507   LHS = ConstantRange(APInt(32, 2), APInt(32, 0));
508   RHS = ConstantRange(APInt(32, 4), APInt(32, 3));
509   EXPECT_EQ(LHS.intersectWith(RHS), ConstantRange(APInt(32, 2), APInt(32, 0)));
510 
511   // [2, 0) /\ [4, 2) = [4, 0)
512   LHS = ConstantRange(APInt(32, 2), APInt(32, 0));
513   RHS = ConstantRange(APInt(32, 4), APInt(32, 2));
514   EXPECT_EQ(LHS.intersectWith(RHS), ConstantRange(APInt(32, 4), APInt(32, 0)));
515 
516   // [4, 2) /\ [5, 1) = [5, 1)
517   LHS = ConstantRange(APInt(32, 4), APInt(32, 2));
518   RHS = ConstantRange(APInt(32, 5), APInt(32, 1));
519   EXPECT_EQ(LHS.intersectWith(RHS), ConstantRange(APInt(32, 5), APInt(32, 1)));
520 
521   // [2, 0) /\ [7, 4) = [7, 4)
522   LHS = ConstantRange(APInt(32, 2), APInt(32, 0));
523   RHS = ConstantRange(APInt(32, 7), APInt(32, 4));
524   EXPECT_EQ(LHS.intersectWith(RHS), ConstantRange(APInt(32, 7), APInt(32, 4)));
525 
526   // [4, 2) /\ [1, 0) = [1, 0)
527   LHS = ConstantRange(APInt(32, 4), APInt(32, 2));
528   RHS = ConstantRange(APInt(32, 1), APInt(32, 0));
529   EXPECT_EQ(LHS.intersectWith(RHS), ConstantRange(APInt(32, 4), APInt(32, 2)));
530 
531   // [15, 0) /\ [7, 6) = [15, 0)
532   LHS = ConstantRange(APInt(32, 15), APInt(32, 0));
533   RHS = ConstantRange(APInt(32, 7), APInt(32, 6));
534   EXPECT_EQ(LHS.intersectWith(RHS), ConstantRange(APInt(32, 15), APInt(32, 0)));
535 }
536 
537 template<typename Fn1, typename Fn2, typename Fn3>
538 void testBinarySetOperationExhaustive(Fn1 OpFn, Fn2 ExactOpFn, Fn3 InResultFn) {
539   unsigned Bits = 4;
540   EnumerateTwoConstantRanges(Bits,
541       [=](const ConstantRange &CR1, const ConstantRange &CR2) {
542         SmallBitVector Elems(1 << Bits);
543         APInt Num(Bits, 0);
544         for (unsigned I = 0, Limit = 1 << Bits; I < Limit; ++I, ++Num)
545           if (InResultFn(CR1, CR2, Num))
546             Elems.set(Num.getZExtValue());
547 
548         ConstantRange SmallestCR = OpFn(CR1, CR2, ConstantRange::Smallest);
549         TestRange(SmallestCR, Elems, PreferSmallest, {CR1, CR2});
550 
551         ConstantRange UnsignedCR = OpFn(CR1, CR2, ConstantRange::Unsigned);
552         TestRange(UnsignedCR, Elems, PreferSmallestNonFullUnsigned, {CR1, CR2});
553 
554         ConstantRange SignedCR = OpFn(CR1, CR2, ConstantRange::Signed);
555         TestRange(SignedCR, Elems, PreferSmallestNonFullSigned, {CR1, CR2});
556 
557         std::optional<ConstantRange> ExactCR = ExactOpFn(CR1, CR2);
558         if (SmallestCR.isSizeLargerThan(Elems.count())) {
559           EXPECT_TRUE(!ExactCR);
560         } else {
561           EXPECT_EQ(SmallestCR, *ExactCR);
562         }
563       });
564 }
565 
566 TEST_F(ConstantRangeTest, IntersectWithExhaustive) {
567   testBinarySetOperationExhaustive(
568       [](const ConstantRange &CR1, const ConstantRange &CR2,
569          ConstantRange::PreferredRangeType Type) {
570         return CR1.intersectWith(CR2, Type);
571       },
572       [](const ConstantRange &CR1, const ConstantRange &CR2) {
573         return CR1.exactIntersectWith(CR2);
574       },
575       [](const ConstantRange &CR1, const ConstantRange &CR2, const APInt &N) {
576         return CR1.contains(N) && CR2.contains(N);
577       });
578 }
579 
580 TEST_F(ConstantRangeTest, UnionWithExhaustive) {
581   testBinarySetOperationExhaustive(
582       [](const ConstantRange &CR1, const ConstantRange &CR2,
583          ConstantRange::PreferredRangeType Type) {
584         return CR1.unionWith(CR2, Type);
585       },
586       [](const ConstantRange &CR1, const ConstantRange &CR2) {
587         return CR1.exactUnionWith(CR2);
588       },
589       [](const ConstantRange &CR1, const ConstantRange &CR2, const APInt &N) {
590         return CR1.contains(N) || CR2.contains(N);
591       });
592 }
593 
594 TEST_F(ConstantRangeTest, UnionWith) {
595   EXPECT_EQ(Wrap.unionWith(One),
596             ConstantRange(APInt(16, 0xaaa), APInt(16, 0xb)));
597   EXPECT_EQ(One.unionWith(Wrap), Wrap.unionWith(One));
598   EXPECT_EQ(Empty.unionWith(Empty), Empty);
599   EXPECT_EQ(Full.unionWith(Full), Full);
600   EXPECT_EQ(Some.unionWith(Wrap), Full);
601 
602   // PR4545
603   EXPECT_EQ(ConstantRange(APInt(16, 14), APInt(16, 1)).unionWith(
604                                     ConstantRange(APInt(16, 0), APInt(16, 8))),
605             ConstantRange(APInt(16, 14), APInt(16, 8)));
606   EXPECT_EQ(ConstantRange(APInt(16, 6), APInt(16, 4)).unionWith(
607                                     ConstantRange(APInt(16, 4), APInt(16, 0))),
608             ConstantRange::getFull(16));
609   EXPECT_EQ(ConstantRange(APInt(16, 1), APInt(16, 0)).unionWith(
610                                     ConstantRange(APInt(16, 2), APInt(16, 1))),
611             ConstantRange::getFull(16));
612 }
613 
614 TEST_F(ConstantRangeTest, SetDifference) {
615   EXPECT_EQ(Full.difference(Empty), Full);
616   EXPECT_EQ(Full.difference(Full), Empty);
617   EXPECT_EQ(Empty.difference(Empty), Empty);
618   EXPECT_EQ(Empty.difference(Full), Empty);
619 
620   ConstantRange A(APInt(16, 3), APInt(16, 7));
621   ConstantRange B(APInt(16, 5), APInt(16, 9));
622   ConstantRange C(APInt(16, 3), APInt(16, 5));
623   ConstantRange D(APInt(16, 7), APInt(16, 9));
624   ConstantRange E(APInt(16, 5), APInt(16, 4));
625   ConstantRange F(APInt(16, 7), APInt(16, 3));
626   EXPECT_EQ(A.difference(B), C);
627   EXPECT_EQ(B.difference(A), D);
628   EXPECT_EQ(E.difference(A), F);
629 }
630 
631 TEST_F(ConstantRangeTest, getActiveBits) {
632   unsigned Bits = 4;
633   EnumerateConstantRanges(Bits, [&](const ConstantRange &CR) {
634     unsigned Exact = 0;
635     ForeachNumInConstantRange(CR, [&](const APInt &N) {
636       Exact = std::max(Exact, N.getActiveBits());
637     });
638 
639     unsigned ResultCR = CR.getActiveBits();
640     EXPECT_EQ(Exact, ResultCR);
641   });
642 }
643 TEST_F(ConstantRangeTest, losslessUnsignedTruncationZeroext) {
644   unsigned Bits = 4;
645   EnumerateConstantRanges(Bits, [&](const ConstantRange &CR) {
646     unsigned MinBitWidth = CR.getActiveBits();
647     if (MinBitWidth == 0) {
648       EXPECT_TRUE(CR.isEmptySet() ||
649                   (CR.isSingleElement() && CR.getSingleElement()->isZero()));
650       return;
651     }
652     if (MinBitWidth == Bits)
653       return;
654     EXPECT_EQ(CR, CR.truncate(MinBitWidth).zeroExtend(Bits));
655   });
656 }
657 
658 TEST_F(ConstantRangeTest, getMinSignedBits) {
659   unsigned Bits = 4;
660   EnumerateConstantRanges(Bits, [&](const ConstantRange &CR) {
661     unsigned Exact = 0;
662     ForeachNumInConstantRange(CR, [&](const APInt &N) {
663       Exact = std::max(Exact, N.getMinSignedBits());
664     });
665 
666     unsigned ResultCR = CR.getMinSignedBits();
667     EXPECT_EQ(Exact, ResultCR);
668   });
669 }
670 TEST_F(ConstantRangeTest, losslessSignedTruncationSignext) {
671   unsigned Bits = 4;
672   EnumerateConstantRanges(Bits, [&](const ConstantRange &CR) {
673     unsigned MinBitWidth = CR.getMinSignedBits();
674     if (MinBitWidth == 0) {
675       EXPECT_TRUE(CR.isEmptySet());
676       return;
677     }
678     if (MinBitWidth == Bits)
679       return;
680     EXPECT_EQ(CR, CR.truncate(MinBitWidth).signExtend(Bits));
681   });
682 }
683 
684 TEST_F(ConstantRangeTest, SubtractAPInt) {
685   EXPECT_EQ(Full.subtract(APInt(16, 4)), Full);
686   EXPECT_EQ(Empty.subtract(APInt(16, 4)), Empty);
687   EXPECT_EQ(Some.subtract(APInt(16, 4)),
688             ConstantRange(APInt(16, 0x6), APInt(16, 0xaa6)));
689   EXPECT_EQ(Wrap.subtract(APInt(16, 4)),
690             ConstantRange(APInt(16, 0xaa6), APInt(16, 0x6)));
691   EXPECT_EQ(One.subtract(APInt(16, 4)),
692             ConstantRange(APInt(16, 0x6)));
693 }
694 
695 TEST_F(ConstantRangeTest, Add) {
696   EXPECT_EQ(Full.add(APInt(16, 4)), Full);
697   EXPECT_EQ(Full.add(Full), Full);
698   EXPECT_EQ(Full.add(Empty), Empty);
699   EXPECT_EQ(Full.add(One), Full);
700   EXPECT_EQ(Full.add(Some), Full);
701   EXPECT_EQ(Full.add(Wrap), Full);
702   EXPECT_EQ(Empty.add(Empty), Empty);
703   EXPECT_EQ(Empty.add(One), Empty);
704   EXPECT_EQ(Empty.add(Some), Empty);
705   EXPECT_EQ(Empty.add(Wrap), Empty);
706   EXPECT_EQ(Empty.add(APInt(16, 4)), Empty);
707   EXPECT_EQ(Some.add(APInt(16, 4)),
708             ConstantRange(APInt(16, 0xe), APInt(16, 0xaae)));
709   EXPECT_EQ(Wrap.add(APInt(16, 4)),
710             ConstantRange(APInt(16, 0xaae), APInt(16, 0xe)));
711   EXPECT_EQ(One.add(APInt(16, 4)),
712             ConstantRange(APInt(16, 0xe)));
713 
714   TestBinaryOpExhaustive(
715       [](const ConstantRange &CR1, const ConstantRange &CR2) {
716         return CR1.add(CR2);
717       },
718       [](const APInt &N1, const APInt &N2) {
719         return N1 + N2;
720       });
721 }
722 
723 TEST_F(ConstantRangeTest, AddWithNoWrap) {
724   typedef OverflowingBinaryOperator OBO;
725   EXPECT_EQ(Empty.addWithNoWrap(Some, OBO::NoSignedWrap), Empty);
726   EXPECT_EQ(Some.addWithNoWrap(Empty, OBO::NoSignedWrap), Empty);
727   EXPECT_EQ(Full.addWithNoWrap(Full, OBO::NoSignedWrap), Full);
728   EXPECT_NE(Full.addWithNoWrap(Some, OBO::NoSignedWrap), Full);
729   EXPECT_NE(Some.addWithNoWrap(Full, OBO::NoSignedWrap), Full);
730   EXPECT_EQ(Full.addWithNoWrap(ConstantRange(APInt(16, 1), APInt(16, 2)),
731                                OBO::NoSignedWrap),
732             ConstantRange(APInt(16, INT16_MIN + 1), APInt(16, INT16_MIN)));
733   EXPECT_EQ(ConstantRange(APInt(16, 1), APInt(16, 2))
734                 .addWithNoWrap(Full, OBO::NoSignedWrap),
735             ConstantRange(APInt(16, INT16_MIN + 1), APInt(16, INT16_MIN)));
736   EXPECT_EQ(Full.addWithNoWrap(ConstantRange(APInt(16, -1), APInt(16, 0)),
737                                OBO::NoSignedWrap),
738             ConstantRange(APInt(16, INT16_MIN), APInt(16, INT16_MAX)));
739   EXPECT_EQ(ConstantRange(APInt(8, 100), APInt(8, 120))
740                 .addWithNoWrap(ConstantRange(APInt(8, 120), APInt(8, 123)),
741                                OBO::NoSignedWrap),
742             ConstantRange(8, false));
743   EXPECT_EQ(ConstantRange(APInt(8, -120), APInt(8, -100))
744                 .addWithNoWrap(ConstantRange(APInt(8, -110), APInt(8, -100)),
745                                OBO::NoSignedWrap),
746             ConstantRange(8, false));
747   EXPECT_EQ(ConstantRange(APInt(8, 0), APInt(8, 101))
748                 .addWithNoWrap(ConstantRange(APInt(8, -128), APInt(8, 28)),
749                                OBO::NoSignedWrap),
750             ConstantRange(8, true));
751   EXPECT_EQ(ConstantRange(APInt(8, 0), APInt(8, 101))
752                 .addWithNoWrap(ConstantRange(APInt(8, -120), APInt(8, 29)),
753                                OBO::NoSignedWrap),
754             ConstantRange(APInt(8, -120), APInt(8, -128)));
755   EXPECT_EQ(ConstantRange(APInt(8, -50), APInt(8, 50))
756                 .addWithNoWrap(ConstantRange(APInt(8, 10), APInt(8, 20)),
757                                OBO::NoSignedWrap),
758             ConstantRange(APInt(8, -40), APInt(8, 69)));
759   EXPECT_EQ(ConstantRange(APInt(8, 10), APInt(8, 20))
760                 .addWithNoWrap(ConstantRange(APInt(8, -50), APInt(8, 50)),
761                                OBO::NoSignedWrap),
762             ConstantRange(APInt(8, -40), APInt(8, 69)));
763   EXPECT_EQ(ConstantRange(APInt(8, 120), APInt(8, -10))
764                 .addWithNoWrap(ConstantRange(APInt(8, 5), APInt(8, 20)),
765                                OBO::NoSignedWrap),
766             ConstantRange(APInt(8, 125), APInt(8, 9)));
767   EXPECT_EQ(ConstantRange(APInt(8, 5), APInt(8, 20))
768                 .addWithNoWrap(ConstantRange(APInt(8, 120), APInt(8, -10)),
769                                OBO::NoSignedWrap),
770             ConstantRange(APInt(8, 125), APInt(8, 9)));
771 
772   TestBinaryOpExhaustive(
773       [](const ConstantRange &CR1, const ConstantRange &CR2) {
774         return CR1.addWithNoWrap(CR2, OBO::NoSignedWrap);
775       },
776       [](const APInt &N1, const APInt &N2) -> Optional<APInt> {
777         bool IsOverflow;
778         APInt Res = N1.sadd_ov(N2, IsOverflow);
779         if (IsOverflow)
780           return std::nullopt;
781         return Res;
782       },
783       PreferSmallest,
784       CheckNonSignWrappedOnly);
785 
786   EXPECT_EQ(Empty.addWithNoWrap(Some, OBO::NoUnsignedWrap), Empty);
787   EXPECT_EQ(Some.addWithNoWrap(Empty, OBO::NoUnsignedWrap), Empty);
788   EXPECT_EQ(Full.addWithNoWrap(Full, OBO::NoUnsignedWrap), Full);
789   EXPECT_NE(Full.addWithNoWrap(Some, OBO::NoUnsignedWrap), Full);
790   EXPECT_NE(Some.addWithNoWrap(Full, OBO::NoUnsignedWrap), Full);
791   EXPECT_EQ(Full.addWithNoWrap(ConstantRange(APInt(16, 1), APInt(16, 2)),
792                                OBO::NoUnsignedWrap),
793             ConstantRange(APInt(16, 1), APInt(16, 0)));
794   EXPECT_EQ(ConstantRange(APInt(16, 1), APInt(16, 2))
795                 .addWithNoWrap(Full, OBO::NoUnsignedWrap),
796             ConstantRange(APInt(16, 1), APInt(16, 0)));
797   EXPECT_EQ(ConstantRange(APInt(8, 200), APInt(8, 220))
798                 .addWithNoWrap(ConstantRange(APInt(8, 100), APInt(8, 123)),
799                                OBO::NoUnsignedWrap),
800             ConstantRange(8, false));
801   EXPECT_EQ(ConstantRange(APInt(8, 0), APInt(8, 101))
802                 .addWithNoWrap(ConstantRange(APInt(8, 0), APInt(8, 156)),
803                                OBO::NoUnsignedWrap),
804             ConstantRange(8, true));
805   EXPECT_EQ(ConstantRange(APInt(8, 0), APInt(8, 101))
806                 .addWithNoWrap(ConstantRange(APInt(8, 10), APInt(8, 29)),
807                                OBO::NoUnsignedWrap),
808             ConstantRange(APInt(8, 10), APInt(8, 129)));
809   EXPECT_EQ(ConstantRange(APInt(8, 20), APInt(8, 10))
810                 .addWithNoWrap(ConstantRange(APInt(8, 50), APInt(8, 200)),
811                                OBO::NoUnsignedWrap),
812             ConstantRange(APInt(8, 50), APInt(8, 0)));
813   EXPECT_EQ(ConstantRange(APInt(8, 10), APInt(8, 20))
814                 .addWithNoWrap(ConstantRange(APInt(8, 50), APInt(8, 200)),
815                                OBO::NoUnsignedWrap),
816             ConstantRange(APInt(8, 60), APInt(8, -37)));
817   EXPECT_EQ(ConstantRange(APInt(8, 20), APInt(8, -30))
818                 .addWithNoWrap(ConstantRange(APInt(8, 5), APInt(8, 20)),
819                                OBO::NoUnsignedWrap),
820             ConstantRange(APInt(8, 25), APInt(8, -11)));
821   EXPECT_EQ(ConstantRange(APInt(8, 5), APInt(8, 20))
822                 .addWithNoWrap(ConstantRange(APInt(8, 20), APInt(8, -30)),
823                                OBO::NoUnsignedWrap),
824             ConstantRange(APInt(8, 25), APInt(8, -11)));
825 
826   TestBinaryOpExhaustive(
827       [](const ConstantRange &CR1, const ConstantRange &CR2) {
828         return CR1.addWithNoWrap(CR2, OBO::NoUnsignedWrap);
829       },
830       [](const APInt &N1, const APInt &N2) -> Optional<APInt> {
831         bool IsOverflow;
832         APInt Res = N1.uadd_ov(N2, IsOverflow);
833         if (IsOverflow)
834           return std::nullopt;
835         return Res;
836       },
837       PreferSmallest,
838       CheckNonWrappedOnly);
839 
840   EXPECT_EQ(ConstantRange(APInt(8, 50), APInt(8, 100))
841                 .addWithNoWrap(ConstantRange(APInt(8, 20), APInt(8, 70)),
842                                OBO::NoSignedWrap),
843             ConstantRange(APInt(8, 70), APInt(8, -128)));
844   EXPECT_EQ(ConstantRange(APInt(8, 50), APInt(8, 100))
845                 .addWithNoWrap(ConstantRange(APInt(8, 20), APInt(8, 70)),
846                                OBO::NoUnsignedWrap),
847             ConstantRange(APInt(8, 70), APInt(8, 169)));
848   EXPECT_EQ(ConstantRange(APInt(8, 50), APInt(8, 100))
849                 .addWithNoWrap(ConstantRange(APInt(8, 20), APInt(8, 70)),
850                                OBO::NoUnsignedWrap | OBO::NoSignedWrap),
851             ConstantRange(APInt(8, 70), APInt(8, -128)));
852 
853   EXPECT_EQ(ConstantRange(APInt(8, -100), APInt(8, -50))
854                 .addWithNoWrap(ConstantRange(APInt(8, 20), APInt(8, 30)),
855                                OBO::NoSignedWrap),
856             ConstantRange(APInt(8, -80), APInt(8, -21)));
857   EXPECT_EQ(ConstantRange(APInt(8, -100), APInt(8, -50))
858                 .addWithNoWrap(ConstantRange(APInt(8, 20), APInt(8, 30)),
859                                OBO::NoUnsignedWrap),
860             ConstantRange(APInt(8, 176), APInt(8, 235)));
861   EXPECT_EQ(ConstantRange(APInt(8, -100), APInt(8, -50))
862                 .addWithNoWrap(ConstantRange(APInt(8, 20), APInt(8, 30)),
863                                OBO::NoUnsignedWrap | OBO::NoSignedWrap),
864             ConstantRange(APInt(8, 176), APInt(8, 235)));
865 
866   TestBinaryOpExhaustive(
867       [](const ConstantRange &CR1, const ConstantRange &CR2) {
868         return CR1.addWithNoWrap(CR2, OBO::NoUnsignedWrap | OBO::NoSignedWrap);
869       },
870       [](const APInt &N1, const APInt &N2) -> Optional<APInt> {
871         bool IsOverflow1, IsOverflow2;
872         APInt Res1 = N1.uadd_ov(N2, IsOverflow1);
873         APInt Res2 = N1.sadd_ov(N2, IsOverflow2);
874         if (IsOverflow1 || IsOverflow2)
875           return std::nullopt;
876         assert(Res1 == Res2 && "Addition results differ?");
877         return Res1;
878       },
879       PreferSmallest,
880       CheckNonWrappedOrSignWrappedOnly);
881 }
882 
883 TEST_F(ConstantRangeTest, Sub) {
884   EXPECT_EQ(Full.sub(APInt(16, 4)), Full);
885   EXPECT_EQ(Full.sub(Full), Full);
886   EXPECT_EQ(Full.sub(Empty), Empty);
887   EXPECT_EQ(Full.sub(One), Full);
888   EXPECT_EQ(Full.sub(Some), Full);
889   EXPECT_EQ(Full.sub(Wrap), Full);
890   EXPECT_EQ(Empty.sub(Empty), Empty);
891   EXPECT_EQ(Empty.sub(One), Empty);
892   EXPECT_EQ(Empty.sub(Some), Empty);
893   EXPECT_EQ(Empty.sub(Wrap), Empty);
894   EXPECT_EQ(Empty.sub(APInt(16, 4)), Empty);
895   EXPECT_EQ(Some.sub(APInt(16, 4)),
896             ConstantRange(APInt(16, 0x6), APInt(16, 0xaa6)));
897   EXPECT_EQ(Some.sub(Some),
898             ConstantRange(APInt(16, 0xf561), APInt(16, 0xaa0)));
899   EXPECT_EQ(Wrap.sub(APInt(16, 4)),
900             ConstantRange(APInt(16, 0xaa6), APInt(16, 0x6)));
901   EXPECT_EQ(One.sub(APInt(16, 4)),
902             ConstantRange(APInt(16, 0x6)));
903 
904   TestBinaryOpExhaustive(
905       [](const ConstantRange &CR1, const ConstantRange &CR2) {
906         return CR1.sub(CR2);
907       },
908       [](const APInt &N1, const APInt &N2) {
909         return N1 - N2;
910       });
911 }
912 
913 TEST_F(ConstantRangeTest, SubWithNoWrap) {
914   typedef OverflowingBinaryOperator OBO;
915   TestBinaryOpExhaustive(
916       [](const ConstantRange &CR1, const ConstantRange &CR2) {
917         return CR1.subWithNoWrap(CR2, OBO::NoSignedWrap);
918       },
919       [](const APInt &N1, const APInt &N2) -> Optional<APInt> {
920         bool IsOverflow;
921         APInt Res = N1.ssub_ov(N2, IsOverflow);
922         if (IsOverflow)
923           return std::nullopt;
924         return Res;
925       },
926       PreferSmallest,
927       CheckNonSignWrappedOnly);
928   TestBinaryOpExhaustive(
929       [](const ConstantRange &CR1, const ConstantRange &CR2) {
930         return CR1.subWithNoWrap(CR2, OBO::NoUnsignedWrap);
931       },
932       [](const APInt &N1, const APInt &N2) -> Optional<APInt> {
933         bool IsOverflow;
934         APInt Res = N1.usub_ov(N2, IsOverflow);
935         if (IsOverflow)
936           return std::nullopt;
937         return Res;
938       },
939       PreferSmallest,
940       CheckNonWrappedOnly);
941   TestBinaryOpExhaustive(
942       [](const ConstantRange &CR1, const ConstantRange &CR2) {
943         return CR1.subWithNoWrap(CR2, OBO::NoUnsignedWrap | OBO::NoSignedWrap);
944       },
945       [](const APInt &N1, const APInt &N2) -> Optional<APInt> {
946         bool IsOverflow1, IsOverflow2;
947         APInt Res1 = N1.usub_ov(N2, IsOverflow1);
948         APInt Res2 = N1.ssub_ov(N2, IsOverflow2);
949         if (IsOverflow1 || IsOverflow2)
950           return std::nullopt;
951         assert(Res1 == Res2 && "Subtraction results differ?");
952         return Res1;
953       },
954       PreferSmallest,
955       CheckNonWrappedOrSignWrappedOnly);
956 }
957 
958 TEST_F(ConstantRangeTest, Multiply) {
959   EXPECT_EQ(Full.multiply(Full), Full);
960   EXPECT_EQ(Full.multiply(Empty), Empty);
961   EXPECT_EQ(Full.multiply(One), Full);
962   EXPECT_EQ(Full.multiply(Some), Full);
963   EXPECT_EQ(Full.multiply(Wrap), Full);
964   EXPECT_EQ(Empty.multiply(Empty), Empty);
965   EXPECT_EQ(Empty.multiply(One), Empty);
966   EXPECT_EQ(Empty.multiply(Some), Empty);
967   EXPECT_EQ(Empty.multiply(Wrap), Empty);
968   EXPECT_EQ(One.multiply(One), ConstantRange(APInt(16, 0xa*0xa),
969                                              APInt(16, 0xa*0xa + 1)));
970   EXPECT_EQ(One.multiply(Some), ConstantRange(APInt(16, 0xa*0xa),
971                                               APInt(16, 0xa*0xaa9 + 1)));
972   EXPECT_EQ(One.multiply(Wrap), Full);
973   EXPECT_EQ(Some.multiply(Some), Full);
974   EXPECT_EQ(Some.multiply(Wrap), Full);
975   EXPECT_EQ(Wrap.multiply(Wrap), Full);
976 
977   ConstantRange Zero(APInt(16, 0));
978   EXPECT_EQ(Zero.multiply(Full), Zero);
979   EXPECT_EQ(Zero.multiply(Some), Zero);
980   EXPECT_EQ(Zero.multiply(Wrap), Zero);
981   EXPECT_EQ(Full.multiply(Zero), Zero);
982   EXPECT_EQ(Some.multiply(Zero), Zero);
983   EXPECT_EQ(Wrap.multiply(Zero), Zero);
984 
985   // http://llvm.org/PR4545
986   EXPECT_EQ(ConstantRange(APInt(4, 1), APInt(4, 6)).multiply(
987                 ConstantRange(APInt(4, 6), APInt(4, 2))),
988             ConstantRange(4, /*isFullSet=*/true));
989 
990   EXPECT_EQ(ConstantRange(APInt(8, 254), APInt(8, 0)).multiply(
991               ConstantRange(APInt(8, 252), APInt(8, 4))),
992             ConstantRange(APInt(8, 250), APInt(8, 9)));
993   EXPECT_EQ(ConstantRange(APInt(8, 254), APInt(8, 255)).multiply(
994               ConstantRange(APInt(8, 2), APInt(8, 4))),
995             ConstantRange(APInt(8, 250), APInt(8, 253)));
996 
997   // TODO: This should be return [-2, 0]
998   EXPECT_EQ(ConstantRange(APInt(8, -2)).multiply(
999               ConstantRange(APInt(8, 0), APInt(8, 2))),
1000             ConstantRange(APInt(8, -2), APInt(8, 1)));
1001 }
1002 
1003 TEST_F(ConstantRangeTest, smul_fast) {
1004   TestBinaryOpExhaustive(
1005       [](const ConstantRange &CR1, const ConstantRange &CR2) {
1006         return CR1.smul_fast(CR2);
1007       },
1008       [](const APInt &N1, const APInt &N2) {
1009         return N1 * N2;
1010       },
1011       PreferSmallest,
1012       [](const ConstantRange &, const ConstantRange &) {
1013         return false; // Check correctness only.
1014       });
1015 }
1016 
1017 TEST_F(ConstantRangeTest, UMax) {
1018   EXPECT_EQ(Full.umax(Full), Full);
1019   EXPECT_EQ(Full.umax(Empty), Empty);
1020   EXPECT_EQ(Full.umax(Some), ConstantRange(APInt(16, 0xa), APInt(16, 0)));
1021   EXPECT_EQ(Full.umax(Wrap), Full);
1022   EXPECT_EQ(Full.umax(Some), ConstantRange(APInt(16, 0xa), APInt(16, 0)));
1023   EXPECT_EQ(Empty.umax(Empty), Empty);
1024   EXPECT_EQ(Empty.umax(Some), Empty);
1025   EXPECT_EQ(Empty.umax(Wrap), Empty);
1026   EXPECT_EQ(Empty.umax(One), Empty);
1027   EXPECT_EQ(Some.umax(Some), Some);
1028   EXPECT_EQ(Some.umax(Wrap), ConstantRange(APInt(16, 0xa), APInt(16, 0)));
1029   EXPECT_EQ(Some.umax(One), Some);
1030   EXPECT_EQ(Wrap.umax(Wrap), Wrap);
1031   EXPECT_EQ(Wrap.umax(One), ConstantRange(APInt(16, 0xa), APInt(16, 0)));
1032   EXPECT_EQ(One.umax(One), One);
1033 
1034   TestBinaryOpExhaustive(
1035       [](const ConstantRange &CR1, const ConstantRange &CR2) {
1036         return CR1.umax(CR2);
1037       },
1038       [](const APInt &N1, const APInt &N2) {
1039         return APIntOps::umax(N1, N2);
1040       },
1041       PreferSmallestNonFullUnsigned);
1042 }
1043 
1044 TEST_F(ConstantRangeTest, SMax) {
1045   EXPECT_EQ(Full.smax(Full), Full);
1046   EXPECT_EQ(Full.smax(Empty), Empty);
1047   EXPECT_EQ(Full.smax(Some), ConstantRange(APInt(16, 0xa),
1048                                            APInt::getSignedMinValue(16)));
1049   EXPECT_EQ(Full.smax(Wrap), Full);
1050   EXPECT_EQ(Full.smax(One), ConstantRange(APInt(16, 0xa),
1051                                           APInt::getSignedMinValue(16)));
1052   EXPECT_EQ(Empty.smax(Empty), Empty);
1053   EXPECT_EQ(Empty.smax(Some), Empty);
1054   EXPECT_EQ(Empty.smax(Wrap), Empty);
1055   EXPECT_EQ(Empty.smax(One), Empty);
1056   EXPECT_EQ(Some.smax(Some), Some);
1057   EXPECT_EQ(Some.smax(Wrap), ConstantRange(APInt(16, 0xa),
1058                                            APInt(16, (uint64_t)INT16_MIN)));
1059   EXPECT_EQ(Some.smax(One), Some);
1060   EXPECT_EQ(Wrap.smax(One), ConstantRange(APInt(16, 0xa),
1061                                           APInt(16, (uint64_t)INT16_MIN)));
1062   EXPECT_EQ(One.smax(One), One);
1063 
1064   TestBinaryOpExhaustive(
1065       [](const ConstantRange &CR1, const ConstantRange &CR2) {
1066         return CR1.smax(CR2);
1067       },
1068       [](const APInt &N1, const APInt &N2) {
1069         return APIntOps::smax(N1, N2);
1070       },
1071       PreferSmallestNonFullSigned);
1072 }
1073 
1074 TEST_F(ConstantRangeTest, UMin) {
1075   EXPECT_EQ(Full.umin(Full), Full);
1076   EXPECT_EQ(Full.umin(Empty), Empty);
1077   EXPECT_EQ(Full.umin(Some), ConstantRange(APInt(16, 0), APInt(16, 0xaaa)));
1078   EXPECT_EQ(Full.umin(Wrap), Full);
1079   EXPECT_EQ(Empty.umin(Empty), Empty);
1080   EXPECT_EQ(Empty.umin(Some), Empty);
1081   EXPECT_EQ(Empty.umin(Wrap), Empty);
1082   EXPECT_EQ(Empty.umin(One), Empty);
1083   EXPECT_EQ(Some.umin(Some), Some);
1084   EXPECT_EQ(Some.umin(Wrap), ConstantRange(APInt(16, 0), APInt(16, 0xaaa)));
1085   EXPECT_EQ(Some.umin(One), One);
1086   EXPECT_EQ(Wrap.umin(Wrap), Wrap);
1087   EXPECT_EQ(Wrap.umin(One), ConstantRange(APInt(16, 0), APInt(16, 0xb)));
1088   EXPECT_EQ(One.umin(One), One);
1089 
1090   TestBinaryOpExhaustive(
1091       [](const ConstantRange &CR1, const ConstantRange &CR2) {
1092         return CR1.umin(CR2);
1093       },
1094       [](const APInt &N1, const APInt &N2) {
1095         return APIntOps::umin(N1, N2);
1096       },
1097       PreferSmallestNonFullUnsigned);
1098 }
1099 
1100 TEST_F(ConstantRangeTest, SMin) {
1101   EXPECT_EQ(Full.smin(Full), Full);
1102   EXPECT_EQ(Full.smin(Empty), Empty);
1103   EXPECT_EQ(Full.smin(Some), ConstantRange(APInt(16, (uint64_t)INT16_MIN),
1104                                            APInt(16, 0xaaa)));
1105   EXPECT_EQ(Full.smin(Wrap), Full);
1106   EXPECT_EQ(Empty.smin(Empty), Empty);
1107   EXPECT_EQ(Empty.smin(Some), Empty);
1108   EXPECT_EQ(Empty.smin(Wrap), Empty);
1109   EXPECT_EQ(Empty.smin(One), Empty);
1110   EXPECT_EQ(Some.smin(Some), Some);
1111   EXPECT_EQ(Some.smin(Wrap), ConstantRange(APInt(16, (uint64_t)INT16_MIN),
1112                                            APInt(16, 0xaaa)));
1113   EXPECT_EQ(Some.smin(One), One);
1114   EXPECT_EQ(Wrap.smin(Wrap), Wrap);
1115   EXPECT_EQ(Wrap.smin(One), ConstantRange(APInt(16, (uint64_t)INT16_MIN),
1116                                           APInt(16, 0xb)));
1117   EXPECT_EQ(One.smin(One), One);
1118 
1119   TestBinaryOpExhaustive(
1120       [](const ConstantRange &CR1, const ConstantRange &CR2) {
1121         return CR1.smin(CR2);
1122       },
1123       [](const APInt &N1, const APInt &N2) {
1124         return APIntOps::smin(N1, N2);
1125       },
1126       PreferSmallestNonFullSigned);
1127 }
1128 
1129 TEST_F(ConstantRangeTest, UDiv) {
1130   EXPECT_EQ(Full.udiv(Full), Full);
1131   EXPECT_EQ(Full.udiv(Empty), Empty);
1132   EXPECT_EQ(Full.udiv(One), ConstantRange(APInt(16, 0),
1133                                           APInt(16, 0xffff / 0xa + 1)));
1134   EXPECT_EQ(Full.udiv(Some), ConstantRange(APInt(16, 0),
1135                                            APInt(16, 0xffff / 0xa + 1)));
1136   EXPECT_EQ(Full.udiv(Wrap), Full);
1137   EXPECT_EQ(Empty.udiv(Empty), Empty);
1138   EXPECT_EQ(Empty.udiv(One), Empty);
1139   EXPECT_EQ(Empty.udiv(Some), Empty);
1140   EXPECT_EQ(Empty.udiv(Wrap), Empty);
1141   EXPECT_EQ(One.udiv(One), ConstantRange(APInt(16, 1)));
1142   EXPECT_EQ(One.udiv(Some), ConstantRange(APInt(16, 0), APInt(16, 2)));
1143   EXPECT_EQ(One.udiv(Wrap), ConstantRange(APInt(16, 0), APInt(16, 0xb)));
1144   EXPECT_EQ(Some.udiv(Some), ConstantRange(APInt(16, 0), APInt(16, 0x111)));
1145   EXPECT_EQ(Some.udiv(Wrap), ConstantRange(APInt(16, 0), APInt(16, 0xaaa)));
1146   EXPECT_EQ(Wrap.udiv(Wrap), Full);
1147 
1148 
1149   ConstantRange Zero(APInt(16, 0));
1150   EXPECT_EQ(Zero.udiv(One), Zero);
1151   EXPECT_EQ(Zero.udiv(Full), Zero);
1152 
1153   EXPECT_EQ(ConstantRange(APInt(16, 0), APInt(16, 99)).udiv(Full),
1154             ConstantRange(APInt(16, 0), APInt(16, 99)));
1155   EXPECT_EQ(ConstantRange(APInt(16, 10), APInt(16, 99)).udiv(Full),
1156             ConstantRange(APInt(16, 0), APInt(16, 99)));
1157 }
1158 
1159 TEST_F(ConstantRangeTest, SDiv) {
1160   ConstantRange OneBit = ConstantRange::getFull(1);
1161   EXPECT_EQ(OneBit.sdiv(OneBit), ConstantRange(APInt(1, 0)));
1162 
1163   unsigned Bits = 4;
1164   EnumerateTwoConstantRanges(Bits, [&](const ConstantRange &CR1,
1165                                        const ConstantRange &CR2) {
1166     // Collect possible results in a bit vector. We store the signed value plus
1167     // a bias to make it unsigned.
1168     int Bias = 1 << (Bits - 1);
1169     BitVector Results(1 << Bits);
1170     ForeachNumInConstantRange(CR1, [&](const APInt &N1) {
1171       ForeachNumInConstantRange(CR2, [&](const APInt &N2) {
1172         // Division by zero is UB.
1173         if (N2 == 0)
1174           return;
1175 
1176         // SignedMin / -1 is UB.
1177         if (N1.isMinSignedValue() && N2.isAllOnes())
1178           return;
1179 
1180         APInt N = N1.sdiv(N2);
1181         Results.set(N.getSExtValue() + Bias);
1182       });
1183     });
1184 
1185     ConstantRange CR = CR1.sdiv(CR2);
1186     if (Results.none()) {
1187       EXPECT_TRUE(CR.isEmptySet());
1188       return;
1189     }
1190 
1191     // If there is a non-full signed envelope, that should be the result.
1192     APInt SMin(Bits, Results.find_first() - Bias);
1193     APInt SMax(Bits, Results.find_last() - Bias);
1194     ConstantRange Envelope = ConstantRange::getNonEmpty(SMin, SMax + 1);
1195     if (!Envelope.isFullSet()) {
1196       EXPECT_EQ(Envelope, CR);
1197       return;
1198     }
1199 
1200     // If the signed envelope is a full set, try to find a smaller sign wrapped
1201     // set that is separated in negative and positive components (or one which
1202     // can also additionally contain zero).
1203     int LastNeg = Results.find_last_in(0, Bias) - Bias;
1204     int LastPos = Results.find_next(Bias) - Bias;
1205     if (Results[Bias]) {
1206       if (LastNeg == -1)
1207         ++LastNeg;
1208       else if (LastPos == 1)
1209         --LastPos;
1210     }
1211 
1212     APInt WMax(Bits, LastNeg);
1213     APInt WMin(Bits, LastPos);
1214     ConstantRange Wrapped = ConstantRange::getNonEmpty(WMin, WMax + 1);
1215     EXPECT_EQ(Wrapped, CR);
1216   });
1217 }
1218 
1219 TEST_F(ConstantRangeTest, URem) {
1220   EXPECT_EQ(Full.urem(Empty), Empty);
1221   EXPECT_EQ(Empty.urem(Full), Empty);
1222   // urem by zero is poison.
1223   EXPECT_EQ(Full.urem(ConstantRange(APInt(16, 0))), Empty);
1224   // urem by full range doesn't contain MaxValue.
1225   EXPECT_EQ(Full.urem(Full), ConstantRange(APInt(16, 0), APInt(16, 0xffff)));
1226   // urem is upper bounded by maximum RHS minus one.
1227   EXPECT_EQ(Full.urem(ConstantRange(APInt(16, 0), APInt(16, 123))),
1228             ConstantRange(APInt(16, 0), APInt(16, 122)));
1229   // urem is upper bounded by maximum LHS.
1230   EXPECT_EQ(ConstantRange(APInt(16, 0), APInt(16, 123)).urem(Full),
1231             ConstantRange(APInt(16, 0), APInt(16, 123)));
1232   // If the LHS is always lower than the RHS, the result is the LHS.
1233   EXPECT_EQ(ConstantRange(APInt(16, 10), APInt(16, 20))
1234                 .urem(ConstantRange(APInt(16, 20), APInt(16, 30))),
1235             ConstantRange(APInt(16, 10), APInt(16, 20)));
1236   // It has to be strictly lower, otherwise the top value may wrap to zero.
1237   EXPECT_EQ(ConstantRange(APInt(16, 10), APInt(16, 20))
1238                 .urem(ConstantRange(APInt(16, 19), APInt(16, 30))),
1239             ConstantRange(APInt(16, 0), APInt(16, 20)));
1240   // [12, 14] % 10 is [2, 4], but we conservatively compute [0, 9].
1241   EXPECT_EQ(ConstantRange(APInt(16, 12), APInt(16, 15))
1242                 .urem(ConstantRange(APInt(16, 10))),
1243             ConstantRange(APInt(16, 0), APInt(16, 10)));
1244 
1245   TestBinaryOpExhaustive(
1246       [](const ConstantRange &CR1, const ConstantRange &CR2) {
1247         return CR1.urem(CR2);
1248       },
1249       [](const APInt &N1, const APInt &N2) -> Optional<APInt> {
1250         if (N2.isZero())
1251           return std::nullopt;
1252         return N1.urem(N2);
1253       },
1254       PreferSmallest,
1255       CheckSingleElementsOnly);
1256 }
1257 
1258 TEST_F(ConstantRangeTest, SRem) {
1259   EXPECT_EQ(Full.srem(Empty), Empty);
1260   EXPECT_EQ(Empty.srem(Full), Empty);
1261   // srem by zero is UB.
1262   EXPECT_EQ(Full.srem(ConstantRange(APInt(16, 0))), Empty);
1263   // srem by full range doesn't contain SignedMinValue.
1264   EXPECT_EQ(Full.srem(Full), ConstantRange(APInt::getSignedMinValue(16) + 1,
1265                                            APInt::getSignedMinValue(16)));
1266 
1267   ConstantRange PosMod(APInt(16, 10), APInt(16, 21));  // [10, 20]
1268   ConstantRange NegMod(APInt(16, -20), APInt(16, -9)); // [-20, -10]
1269   ConstantRange IntMinMod(APInt::getSignedMinValue(16));
1270 
1271   ConstantRange Expected(16, true);
1272 
1273   // srem is bounded by abs(RHS) minus one.
1274   ConstantRange PosLargeLHS(APInt(16, 0), APInt(16, 41));
1275   Expected = ConstantRange(APInt(16, 0), APInt(16, 20));
1276   EXPECT_EQ(PosLargeLHS.srem(PosMod), Expected);
1277   EXPECT_EQ(PosLargeLHS.srem(NegMod), Expected);
1278   ConstantRange NegLargeLHS(APInt(16, -40), APInt(16, 1));
1279   Expected = ConstantRange(APInt(16, -19), APInt(16, 1));
1280   EXPECT_EQ(NegLargeLHS.srem(PosMod), Expected);
1281   EXPECT_EQ(NegLargeLHS.srem(NegMod), Expected);
1282   ConstantRange PosNegLargeLHS(APInt(16, -32), APInt(16, 38));
1283   Expected = ConstantRange(APInt(16, -19), APInt(16, 20));
1284   EXPECT_EQ(PosNegLargeLHS.srem(PosMod), Expected);
1285   EXPECT_EQ(PosNegLargeLHS.srem(NegMod), Expected);
1286 
1287   // srem is bounded by LHS.
1288   ConstantRange PosLHS(APInt(16, 0), APInt(16, 16));
1289   EXPECT_EQ(PosLHS.srem(PosMod), PosLHS);
1290   EXPECT_EQ(PosLHS.srem(NegMod), PosLHS);
1291   EXPECT_EQ(PosLHS.srem(IntMinMod), PosLHS);
1292   ConstantRange NegLHS(APInt(16, -15), APInt(16, 1));
1293   EXPECT_EQ(NegLHS.srem(PosMod), NegLHS);
1294   EXPECT_EQ(NegLHS.srem(NegMod), NegLHS);
1295   EXPECT_EQ(NegLHS.srem(IntMinMod), NegLHS);
1296   ConstantRange PosNegLHS(APInt(16, -12), APInt(16, 18));
1297   EXPECT_EQ(PosNegLHS.srem(PosMod), PosNegLHS);
1298   EXPECT_EQ(PosNegLHS.srem(NegMod), PosNegLHS);
1299   EXPECT_EQ(PosNegLHS.srem(IntMinMod), PosNegLHS);
1300 
1301   // srem is LHS if it is smaller than RHS.
1302   ConstantRange PosSmallLHS(APInt(16, 3), APInt(16, 8));
1303   EXPECT_EQ(PosSmallLHS.srem(PosMod), PosSmallLHS);
1304   EXPECT_EQ(PosSmallLHS.srem(NegMod), PosSmallLHS);
1305   EXPECT_EQ(PosSmallLHS.srem(IntMinMod), PosSmallLHS);
1306   ConstantRange NegSmallLHS(APInt(16, -7), APInt(16, -2));
1307   EXPECT_EQ(NegSmallLHS.srem(PosMod), NegSmallLHS);
1308   EXPECT_EQ(NegSmallLHS.srem(NegMod), NegSmallLHS);
1309   EXPECT_EQ(NegSmallLHS.srem(IntMinMod), NegSmallLHS);
1310   ConstantRange PosNegSmallLHS(APInt(16, -3), APInt(16, 8));
1311   EXPECT_EQ(PosNegSmallLHS.srem(PosMod), PosNegSmallLHS);
1312   EXPECT_EQ(PosNegSmallLHS.srem(NegMod), PosNegSmallLHS);
1313   EXPECT_EQ(PosNegSmallLHS.srem(IntMinMod), PosNegSmallLHS);
1314 
1315   // Example of a suboptimal result:
1316   // [12, 14] srem 10 is [2, 4], but we conservatively compute [0, 9].
1317   EXPECT_EQ(ConstantRange(APInt(16, 12), APInt(16, 15))
1318                 .srem(ConstantRange(APInt(16, 10))),
1319             ConstantRange(APInt(16, 0), APInt(16, 10)));
1320 
1321   TestBinaryOpExhaustive(
1322       [](const ConstantRange &CR1, const ConstantRange &CR2) {
1323         return CR1.srem(CR2);
1324       },
1325       [](const APInt &N1, const APInt &N2) -> Optional<APInt> {
1326         if (N2.isZero())
1327           return std::nullopt;
1328         return N1.srem(N2);
1329       },
1330       PreferSmallest,
1331       CheckSingleElementsOnly);
1332 }
1333 
1334 TEST_F(ConstantRangeTest, Shl) {
1335   ConstantRange Some2(APInt(16, 0xfff), APInt(16, 0x8000));
1336   ConstantRange WrapNullMax(APInt(16, 0x1), APInt(16, 0x0));
1337   EXPECT_EQ(Full.shl(Full), Full);
1338   EXPECT_EQ(Full.shl(Empty), Empty);
1339   EXPECT_EQ(Full.shl(One), ConstantRange(APInt(16, 0),
1340                                          APInt(16, 0xfc00) + 1));
1341   EXPECT_EQ(Full.shl(Some), Full);   // TODO: [0, (-1 << 0xa) + 1)
1342   EXPECT_EQ(Full.shl(Wrap), Full);
1343   EXPECT_EQ(Empty.shl(Empty), Empty);
1344   EXPECT_EQ(Empty.shl(One), Empty);
1345   EXPECT_EQ(Empty.shl(Some), Empty);
1346   EXPECT_EQ(Empty.shl(Wrap), Empty);
1347   EXPECT_EQ(One.shl(One), ConstantRange(APInt(16, 0xa << 0xa),
1348                                         APInt(16, (0xa << 0xa) + 1)));
1349   EXPECT_EQ(One.shl(Some), Full);    // TODO: [0xa << 0xa, 0)
1350   EXPECT_EQ(One.shl(Wrap), Full);    // TODO: [0xa, 0xa << 14 + 1)
1351   EXPECT_EQ(Some.shl(Some), Full);   // TODO: [0xa << 0xa, 0xfc01)
1352   EXPECT_EQ(Some.shl(Wrap), Full);   // TODO: [0xa, 0x7ff << 0x5 + 1)
1353   EXPECT_EQ(Wrap.shl(Wrap), Full);
1354   EXPECT_EQ(
1355       Some2.shl(ConstantRange(APInt(16, 0x1))),
1356       ConstantRange(APInt(16, 0xfff << 0x1), APInt(16, 0x7fff << 0x1) + 1));
1357   EXPECT_EQ(One.shl(WrapNullMax), Full);
1358 
1359   TestBinaryOpExhaustive(
1360       [](const ConstantRange &CR1, const ConstantRange &CR2) {
1361         return CR1.shl(CR2);
1362       },
1363       [](const APInt &N1, const APInt &N2) -> Optional<APInt> {
1364         if (N2.uge(N2.getBitWidth()))
1365           return std::nullopt;
1366         return N1.shl(N2);
1367       },
1368       PreferSmallestUnsigned,
1369       [](const ConstantRange &, const ConstantRange &CR2) {
1370         // We currently only produce precise results for single element RHS.
1371         return CR2.isSingleElement();
1372       });
1373 }
1374 
1375 TEST_F(ConstantRangeTest, Lshr) {
1376   EXPECT_EQ(Full.lshr(Full), Full);
1377   EXPECT_EQ(Full.lshr(Empty), Empty);
1378   EXPECT_EQ(Full.lshr(One), ConstantRange(APInt(16, 0),
1379                                           APInt(16, (0xffff >> 0xa) + 1)));
1380   EXPECT_EQ(Full.lshr(Some), ConstantRange(APInt(16, 0),
1381                                            APInt(16, (0xffff >> 0xa) + 1)));
1382   EXPECT_EQ(Full.lshr(Wrap), Full);
1383   EXPECT_EQ(Empty.lshr(Empty), Empty);
1384   EXPECT_EQ(Empty.lshr(One), Empty);
1385   EXPECT_EQ(Empty.lshr(Some), Empty);
1386   EXPECT_EQ(Empty.lshr(Wrap), Empty);
1387   EXPECT_EQ(One.lshr(One), ConstantRange(APInt(16, 0)));
1388   EXPECT_EQ(One.lshr(Some), ConstantRange(APInt(16, 0)));
1389   EXPECT_EQ(One.lshr(Wrap), ConstantRange(APInt(16, 0), APInt(16, 0xb)));
1390   EXPECT_EQ(Some.lshr(Some), ConstantRange(APInt(16, 0),
1391                                            APInt(16, (0xaaa >> 0xa) + 1)));
1392   EXPECT_EQ(Some.lshr(Wrap), ConstantRange(APInt(16, 0), APInt(16, 0xaaa)));
1393   EXPECT_EQ(Wrap.lshr(Wrap), Full);
1394 }
1395 
1396 TEST_F(ConstantRangeTest, Ashr) {
1397   EXPECT_EQ(Full.ashr(Full), Full);
1398   EXPECT_EQ(Full.ashr(Empty), Empty);
1399   EXPECT_EQ(Full.ashr(One), ConstantRange(APInt(16, 0xffe0),
1400                                           APInt(16, (0x7fff >> 0xa) + 1 )));
1401   ConstantRange Small(APInt(16, 0xa), APInt(16, 0xb));
1402   EXPECT_EQ(Full.ashr(Small), ConstantRange(APInt(16, 0xffe0),
1403                                            APInt(16, (0x7fff >> 0xa) + 1 )));
1404   EXPECT_EQ(Full.ashr(Some), ConstantRange(APInt(16, 0xffe0),
1405                                            APInt(16, (0x7fff >> 0xa) + 1 )));
1406   EXPECT_EQ(Full.ashr(Wrap), Full);
1407   EXPECT_EQ(Empty.ashr(Empty), Empty);
1408   EXPECT_EQ(Empty.ashr(One), Empty);
1409   EXPECT_EQ(Empty.ashr(Some), Empty);
1410   EXPECT_EQ(Empty.ashr(Wrap), Empty);
1411   EXPECT_EQ(One.ashr(One), ConstantRange(APInt(16, 0)));
1412   EXPECT_EQ(One.ashr(Some), ConstantRange(APInt(16, 0)));
1413   EXPECT_EQ(One.ashr(Wrap), ConstantRange(APInt(16, 0), APInt(16, 0xb)));
1414   EXPECT_EQ(Some.ashr(Some), ConstantRange(APInt(16, 0),
1415                                            APInt(16, (0xaaa >> 0xa) + 1)));
1416   EXPECT_EQ(Some.ashr(Wrap), ConstantRange(APInt(16, 0), APInt(16, 0xaaa)));
1417   EXPECT_EQ(Wrap.ashr(Wrap), Full);
1418   ConstantRange Neg(APInt(16, 0xf3f0, true), APInt(16, 0xf7f8, true));
1419   EXPECT_EQ(Neg.ashr(Small), ConstantRange(APInt(16, 0xfffc, true),
1420                                            APInt(16, 0xfffe, true)));
1421 }
1422 
1423 TEST(ConstantRange, MakeAllowedICmpRegion) {
1424   // PR8250
1425   ConstantRange SMax = ConstantRange(APInt::getSignedMaxValue(32));
1426   EXPECT_TRUE(ConstantRange::makeAllowedICmpRegion(ICmpInst::ICMP_SGT, SMax)
1427                   .isEmptySet());
1428 }
1429 
1430 TEST(ConstantRange, MakeSatisfyingICmpRegion) {
1431   ConstantRange LowHalf(APInt(8, 0), APInt(8, 128));
1432   ConstantRange HighHalf(APInt(8, 128), APInt(8, 0));
1433   ConstantRange EmptySet(8, /* isFullSet = */ false);
1434 
1435   EXPECT_EQ(ConstantRange::makeSatisfyingICmpRegion(ICmpInst::ICMP_NE, LowHalf),
1436             HighHalf);
1437 
1438   EXPECT_EQ(
1439       ConstantRange::makeSatisfyingICmpRegion(ICmpInst::ICMP_NE, HighHalf),
1440       LowHalf);
1441 
1442   EXPECT_TRUE(ConstantRange::makeSatisfyingICmpRegion(ICmpInst::ICMP_EQ,
1443                                                       HighHalf).isEmptySet());
1444 
1445   ConstantRange UnsignedSample(APInt(8, 5), APInt(8, 200));
1446 
1447   EXPECT_EQ(ConstantRange::makeSatisfyingICmpRegion(ICmpInst::ICMP_ULT,
1448                                                     UnsignedSample),
1449             ConstantRange(APInt(8, 0), APInt(8, 5)));
1450 
1451   EXPECT_EQ(ConstantRange::makeSatisfyingICmpRegion(ICmpInst::ICMP_ULE,
1452                                                     UnsignedSample),
1453             ConstantRange(APInt(8, 0), APInt(8, 6)));
1454 
1455   EXPECT_EQ(ConstantRange::makeSatisfyingICmpRegion(ICmpInst::ICMP_UGT,
1456                                                     UnsignedSample),
1457             ConstantRange(APInt(8, 200), APInt(8, 0)));
1458 
1459   EXPECT_EQ(ConstantRange::makeSatisfyingICmpRegion(ICmpInst::ICMP_UGE,
1460                                                     UnsignedSample),
1461             ConstantRange(APInt(8, 199), APInt(8, 0)));
1462 
1463   ConstantRange SignedSample(APInt(8, -5), APInt(8, 5));
1464 
1465   EXPECT_EQ(
1466       ConstantRange::makeSatisfyingICmpRegion(ICmpInst::ICMP_SLT, SignedSample),
1467       ConstantRange(APInt(8, -128), APInt(8, -5)));
1468 
1469   EXPECT_EQ(
1470       ConstantRange::makeSatisfyingICmpRegion(ICmpInst::ICMP_SLE, SignedSample),
1471       ConstantRange(APInt(8, -128), APInt(8, -4)));
1472 
1473   EXPECT_EQ(
1474       ConstantRange::makeSatisfyingICmpRegion(ICmpInst::ICMP_SGT, SignedSample),
1475       ConstantRange(APInt(8, 5), APInt(8, -128)));
1476 
1477   EXPECT_EQ(
1478       ConstantRange::makeSatisfyingICmpRegion(ICmpInst::ICMP_SGE, SignedSample),
1479       ConstantRange(APInt(8, 4), APInt(8, -128)));
1480 }
1481 
1482 void ICmpTestImpl(CmpInst::Predicate Pred) {
1483   unsigned Bits = 4;
1484   EnumerateTwoConstantRanges(
1485       Bits, [&](const ConstantRange &CR1, const ConstantRange &CR2) {
1486         bool Exhaustive = true;
1487         ForeachNumInConstantRange(CR1, [&](const APInt &N1) {
1488           ForeachNumInConstantRange(CR2, [&](const APInt &N2) {
1489             Exhaustive &= ICmpInst::compare(N1, N2, Pred);
1490           });
1491         });
1492         EXPECT_EQ(CR1.icmp(Pred, CR2), Exhaustive);
1493       });
1494 }
1495 
1496 TEST(ConstantRange, ICmp) {
1497   for (auto Pred : ICmpInst::predicates())
1498     ICmpTestImpl(Pred);
1499 }
1500 
1501 TEST(ConstantRange, MakeGuaranteedNoWrapRegion) {
1502   const int IntMin4Bits = 8;
1503   const int IntMax4Bits = 7;
1504   typedef OverflowingBinaryOperator OBO;
1505 
1506   for (int Const : {0, -1, -2, 1, 2, IntMin4Bits, IntMax4Bits}) {
1507     APInt C(4, Const, true /* = isSigned */);
1508 
1509     auto NUWRegion = ConstantRange::makeGuaranteedNoWrapRegion(
1510         Instruction::Add, C, OBO::NoUnsignedWrap);
1511 
1512     EXPECT_FALSE(NUWRegion.isEmptySet());
1513 
1514     auto NSWRegion = ConstantRange::makeGuaranteedNoWrapRegion(
1515         Instruction::Add, C, OBO::NoSignedWrap);
1516 
1517     EXPECT_FALSE(NSWRegion.isEmptySet());
1518 
1519     for (APInt I = NUWRegion.getLower(), E = NUWRegion.getUpper(); I != E;
1520          ++I) {
1521       bool Overflow = false;
1522       (void)I.uadd_ov(C, Overflow);
1523       EXPECT_FALSE(Overflow);
1524     }
1525 
1526     for (APInt I = NSWRegion.getLower(), E = NSWRegion.getUpper(); I != E;
1527          ++I) {
1528       bool Overflow = false;
1529       (void)I.sadd_ov(C, Overflow);
1530       EXPECT_FALSE(Overflow);
1531     }
1532   }
1533 
1534   for (int Const : {0, -1, -2, 1, 2, IntMin4Bits, IntMax4Bits}) {
1535     APInt C(4, Const, true /* = isSigned */);
1536 
1537     auto NUWRegion = ConstantRange::makeGuaranteedNoWrapRegion(
1538         Instruction::Sub, C, OBO::NoUnsignedWrap);
1539 
1540     EXPECT_FALSE(NUWRegion.isEmptySet());
1541 
1542     auto NSWRegion = ConstantRange::makeGuaranteedNoWrapRegion(
1543         Instruction::Sub, C, OBO::NoSignedWrap);
1544 
1545     EXPECT_FALSE(NSWRegion.isEmptySet());
1546 
1547     for (APInt I = NUWRegion.getLower(), E = NUWRegion.getUpper(); I != E;
1548          ++I) {
1549       bool Overflow = false;
1550       (void)I.usub_ov(C, Overflow);
1551       EXPECT_FALSE(Overflow);
1552     }
1553 
1554     for (APInt I = NSWRegion.getLower(), E = NSWRegion.getUpper(); I != E;
1555          ++I) {
1556       bool Overflow = false;
1557       (void)I.ssub_ov(C, Overflow);
1558       EXPECT_FALSE(Overflow);
1559     }
1560   }
1561 
1562   auto NSWForAllValues = ConstantRange::makeGuaranteedNoWrapRegion(
1563       Instruction::Add, ConstantRange(32, /* isFullSet = */ true),
1564       OBO::NoSignedWrap);
1565   EXPECT_TRUE(NSWForAllValues.isSingleElement() &&
1566               NSWForAllValues.getSingleElement()->isMinValue());
1567 
1568   NSWForAllValues = ConstantRange::makeGuaranteedNoWrapRegion(
1569       Instruction::Sub, ConstantRange(32, /* isFullSet = */ true),
1570       OBO::NoSignedWrap);
1571   EXPECT_TRUE(NSWForAllValues.isSingleElement() &&
1572               NSWForAllValues.getSingleElement()->isMaxValue());
1573 
1574   auto NUWForAllValues = ConstantRange::makeGuaranteedNoWrapRegion(
1575       Instruction::Add, ConstantRange(32, /* isFullSet = */ true),
1576       OBO::NoUnsignedWrap);
1577   EXPECT_TRUE(NUWForAllValues.isSingleElement() &&
1578               NUWForAllValues.getSingleElement()->isMinValue());
1579 
1580   NUWForAllValues = ConstantRange::makeGuaranteedNoWrapRegion(
1581       Instruction::Sub, ConstantRange(32, /* isFullSet = */ true),
1582       OBO::NoUnsignedWrap);
1583   EXPECT_TRUE(NUWForAllValues.isSingleElement() &&
1584               NUWForAllValues.getSingleElement()->isMaxValue());
1585 
1586   EXPECT_TRUE(ConstantRange::makeGuaranteedNoWrapRegion(
1587       Instruction::Add, APInt(32, 0), OBO::NoUnsignedWrap).isFullSet());
1588   EXPECT_TRUE(ConstantRange::makeGuaranteedNoWrapRegion(
1589       Instruction::Add, APInt(32, 0), OBO::NoSignedWrap).isFullSet());
1590   EXPECT_TRUE(ConstantRange::makeGuaranteedNoWrapRegion(
1591       Instruction::Sub, APInt(32, 0), OBO::NoUnsignedWrap).isFullSet());
1592   EXPECT_TRUE(ConstantRange::makeGuaranteedNoWrapRegion(
1593       Instruction::Sub, APInt(32, 0), OBO::NoSignedWrap).isFullSet());
1594 
1595   ConstantRange OneToFive(APInt(32, 1), APInt(32, 6));
1596   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1597                 Instruction::Add, OneToFive, OBO::NoSignedWrap),
1598             ConstantRange(APInt::getSignedMinValue(32),
1599                           APInt::getSignedMaxValue(32) - 4));
1600   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1601                 Instruction::Add, OneToFive, OBO::NoUnsignedWrap),
1602             ConstantRange(APInt::getMinValue(32), APInt::getMinValue(32) - 5));
1603   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1604                 Instruction::Sub, OneToFive, OBO::NoSignedWrap),
1605             ConstantRange(APInt::getSignedMinValue(32) + 5,
1606                           APInt::getSignedMinValue(32)));
1607   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1608                 Instruction::Sub, OneToFive, OBO::NoUnsignedWrap),
1609             ConstantRange(APInt::getMinValue(32) + 5, APInt::getMinValue(32)));
1610 
1611   ConstantRange MinusFiveToMinusTwo(APInt(32, -5), APInt(32, -1));
1612   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1613                 Instruction::Add, MinusFiveToMinusTwo, OBO::NoSignedWrap),
1614             ConstantRange(APInt::getSignedMinValue(32) + 5,
1615                           APInt::getSignedMinValue(32)));
1616   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1617                 Instruction::Add, MinusFiveToMinusTwo, OBO::NoUnsignedWrap),
1618             ConstantRange(APInt(32, 0), APInt(32, 2)));
1619   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1620                 Instruction::Sub, MinusFiveToMinusTwo, OBO::NoSignedWrap),
1621             ConstantRange(APInt::getSignedMinValue(32),
1622                           APInt::getSignedMaxValue(32) - 4));
1623   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1624                 Instruction::Sub, MinusFiveToMinusTwo, OBO::NoUnsignedWrap),
1625             ConstantRange(APInt::getMaxValue(32) - 1,
1626                           APInt::getMinValue(32)));
1627 
1628   ConstantRange MinusOneToOne(APInt(32, -1), APInt(32, 2));
1629   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1630                 Instruction::Add, MinusOneToOne, OBO::NoSignedWrap),
1631             ConstantRange(APInt::getSignedMinValue(32) + 1,
1632                           APInt::getSignedMinValue(32) - 1));
1633   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1634                 Instruction::Add, MinusOneToOne, OBO::NoUnsignedWrap),
1635             ConstantRange(APInt(32, 0), APInt(32, 1)));
1636   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1637                 Instruction::Sub, MinusOneToOne, OBO::NoSignedWrap),
1638             ConstantRange(APInt::getSignedMinValue(32) + 1,
1639                           APInt::getSignedMinValue(32) - 1));
1640   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1641                 Instruction::Sub, MinusOneToOne, OBO::NoUnsignedWrap),
1642             ConstantRange(APInt::getMaxValue(32),
1643                           APInt::getMinValue(32)));
1644 
1645   ConstantRange One(APInt(32, 1), APInt(32, 2));
1646   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1647                 Instruction::Add, One, OBO::NoSignedWrap),
1648             ConstantRange(APInt::getSignedMinValue(32),
1649                           APInt::getSignedMaxValue(32)));
1650   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1651                 Instruction::Add, One, OBO::NoUnsignedWrap),
1652             ConstantRange(APInt::getMinValue(32), APInt::getMaxValue(32)));
1653   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1654                 Instruction::Sub, One, OBO::NoSignedWrap),
1655             ConstantRange(APInt::getSignedMinValue(32) + 1,
1656                           APInt::getSignedMinValue(32)));
1657   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1658                 Instruction::Sub, One, OBO::NoUnsignedWrap),
1659             ConstantRange(APInt::getMinValue(32) + 1, APInt::getMinValue(32)));
1660 
1661   ConstantRange OneLessThanBitWidth(APInt(32, 0), APInt(32, 31) + 1);
1662   ConstantRange UpToBitWidth(APInt(32, 0), APInt(32, 32) + 1);
1663   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1664                 Instruction::Shl, UpToBitWidth, OBO::NoUnsignedWrap),
1665             ConstantRange::makeGuaranteedNoWrapRegion(
1666                 Instruction::Shl, OneLessThanBitWidth, OBO::NoUnsignedWrap));
1667   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1668                 Instruction::Shl, UpToBitWidth, OBO::NoSignedWrap),
1669             ConstantRange::makeGuaranteedNoWrapRegion(
1670                 Instruction::Shl, OneLessThanBitWidth, OBO::NoSignedWrap));
1671   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1672                 Instruction::Shl, UpToBitWidth, OBO::NoUnsignedWrap),
1673             ConstantRange(APInt(32, 0), APInt(32, 1) + 1));
1674   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1675                 Instruction::Shl, UpToBitWidth, OBO::NoSignedWrap),
1676             ConstantRange(APInt(32, -1), APInt(32, 0) + 1));
1677 
1678   EXPECT_EQ(
1679       ConstantRange::makeGuaranteedNoWrapRegion(
1680           Instruction::Shl, ConstantRange::getFull(32), OBO::NoUnsignedWrap),
1681       ConstantRange::makeGuaranteedNoWrapRegion(
1682           Instruction::Shl, OneLessThanBitWidth, OBO::NoUnsignedWrap));
1683   EXPECT_EQ(
1684       ConstantRange::makeGuaranteedNoWrapRegion(
1685           Instruction::Shl, ConstantRange::getFull(32), OBO::NoSignedWrap),
1686       ConstantRange::makeGuaranteedNoWrapRegion(
1687           Instruction::Shl, OneLessThanBitWidth, OBO::NoSignedWrap));
1688 
1689   ConstantRange IllegalShAmt(APInt(32, 32), APInt(32, 0) + 1);
1690   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1691                 Instruction::Shl, IllegalShAmt, OBO::NoUnsignedWrap),
1692             ConstantRange::getFull(32));
1693   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1694                 Instruction::Shl, IllegalShAmt, OBO::NoSignedWrap),
1695             ConstantRange::getFull(32));
1696 
1697   EXPECT_EQ(
1698       ConstantRange::makeGuaranteedNoWrapRegion(
1699           Instruction::Shl, ConstantRange(APInt(32, -32), APInt(32, 16) + 1),
1700           OBO::NoUnsignedWrap),
1701       ConstantRange::makeGuaranteedNoWrapRegion(
1702           Instruction::Shl, ConstantRange(APInt(32, 0), APInt(32, 16) + 1),
1703           OBO::NoUnsignedWrap));
1704   EXPECT_EQ(
1705       ConstantRange::makeGuaranteedNoWrapRegion(
1706           Instruction::Shl, ConstantRange(APInt(32, -32), APInt(32, 16) + 1),
1707           OBO::NoSignedWrap),
1708       ConstantRange::makeGuaranteedNoWrapRegion(
1709           Instruction::Shl, ConstantRange(APInt(32, 0), APInt(32, 16) + 1),
1710           OBO::NoSignedWrap));
1711 
1712   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1713                 Instruction::Shl,
1714                 ConstantRange(APInt(32, -32), APInt(32, 16) + 1),
1715                 OBO::NoUnsignedWrap),
1716             ConstantRange(APInt(32, 0), APInt(32, 65535) + 1));
1717   EXPECT_EQ(ConstantRange::makeGuaranteedNoWrapRegion(
1718                 Instruction::Shl,
1719                 ConstantRange(APInt(32, -32), APInt(32, 16) + 1),
1720                 OBO::NoSignedWrap),
1721             ConstantRange(APInt(32, -32768), APInt(32, 32767) + 1));
1722 }
1723 
1724 template<typename Fn>
1725 void TestNoWrapRegionExhaustive(Instruction::BinaryOps BinOp,
1726                                 unsigned NoWrapKind, Fn OverflowFn) {
1727   unsigned Bits = 5;
1728   EnumerateConstantRanges(Bits, [&](const ConstantRange &CR) {
1729     if (CR.isEmptySet())
1730       return;
1731     if (Instruction::isShift(BinOp) && CR.getUnsignedMax().uge(Bits))
1732       return;
1733 
1734     ConstantRange NoWrap =
1735         ConstantRange::makeGuaranteedNoWrapRegion(BinOp, CR, NoWrapKind);
1736     EnumerateAPInts(Bits, [&](const APInt &N1) {
1737       bool NoOverflow = true;
1738       bool Overflow = true;
1739       ForeachNumInConstantRange(CR, [&](const APInt &N2) {
1740         if (OverflowFn(N1, N2))
1741           NoOverflow = false;
1742         else
1743           Overflow = false;
1744       });
1745       EXPECT_EQ(NoOverflow, NoWrap.contains(N1));
1746 
1747       // The no-wrap range is exact for single-element ranges.
1748       if (CR.isSingleElement()) {
1749         EXPECT_EQ(Overflow, !NoWrap.contains(N1));
1750       }
1751     });
1752   });
1753 }
1754 
1755 // Show that makeGuaranteedNoWrapRegion() is maximal, and for single-element
1756 // ranges also exact.
1757 TEST(ConstantRange, NoWrapRegionExhaustive) {
1758   TestNoWrapRegionExhaustive(
1759       Instruction::Add, OverflowingBinaryOperator::NoUnsignedWrap,
1760       [](const APInt &N1, const APInt &N2) {
1761         bool Overflow;
1762         (void) N1.uadd_ov(N2, Overflow);
1763         return Overflow;
1764       });
1765   TestNoWrapRegionExhaustive(
1766       Instruction::Add, OverflowingBinaryOperator::NoSignedWrap,
1767       [](const APInt &N1, const APInt &N2) {
1768         bool Overflow;
1769         (void) N1.sadd_ov(N2, Overflow);
1770         return Overflow;
1771       });
1772   TestNoWrapRegionExhaustive(
1773       Instruction::Sub, OverflowingBinaryOperator::NoUnsignedWrap,
1774       [](const APInt &N1, const APInt &N2) {
1775         bool Overflow;
1776         (void) N1.usub_ov(N2, Overflow);
1777         return Overflow;
1778       });
1779   TestNoWrapRegionExhaustive(
1780       Instruction::Sub, OverflowingBinaryOperator::NoSignedWrap,
1781       [](const APInt &N1, const APInt &N2) {
1782         bool Overflow;
1783         (void) N1.ssub_ov(N2, Overflow);
1784         return Overflow;
1785       });
1786   TestNoWrapRegionExhaustive(
1787       Instruction::Mul, OverflowingBinaryOperator::NoUnsignedWrap,
1788       [](const APInt &N1, const APInt &N2) {
1789         bool Overflow;
1790         (void) N1.umul_ov(N2, Overflow);
1791         return Overflow;
1792       });
1793   TestNoWrapRegionExhaustive(
1794       Instruction::Mul, OverflowingBinaryOperator::NoSignedWrap,
1795       [](const APInt &N1, const APInt &N2) {
1796         bool Overflow;
1797         (void) N1.smul_ov(N2, Overflow);
1798         return Overflow;
1799       });
1800   TestNoWrapRegionExhaustive(Instruction::Shl,
1801                              OverflowingBinaryOperator::NoUnsignedWrap,
1802                              [](const APInt &N1, const APInt &N2) {
1803                                bool Overflow;
1804                                (void)N1.ushl_ov(N2, Overflow);
1805                                return Overflow;
1806                              });
1807   TestNoWrapRegionExhaustive(Instruction::Shl,
1808                              OverflowingBinaryOperator::NoSignedWrap,
1809                              [](const APInt &N1, const APInt &N2) {
1810                                bool Overflow;
1811                                (void)N1.sshl_ov(N2, Overflow);
1812                                return Overflow;
1813                              });
1814 }
1815 
1816 TEST(ConstantRange, GetEquivalentICmp) {
1817   APInt RHS;
1818   CmpInst::Predicate Pred;
1819 
1820   EXPECT_TRUE(ConstantRange(APInt::getMinValue(32), APInt(32, 100))
1821                   .getEquivalentICmp(Pred, RHS));
1822   EXPECT_EQ(Pred, CmpInst::ICMP_ULT);
1823   EXPECT_EQ(RHS, APInt(32, 100));
1824 
1825   EXPECT_TRUE(ConstantRange(APInt::getSignedMinValue(32), APInt(32, 100))
1826                   .getEquivalentICmp(Pred, RHS));
1827   EXPECT_EQ(Pred, CmpInst::ICMP_SLT);
1828   EXPECT_EQ(RHS, APInt(32, 100));
1829 
1830   EXPECT_TRUE(ConstantRange(APInt(32, 100), APInt::getMinValue(32))
1831                   .getEquivalentICmp(Pred, RHS));
1832   EXPECT_EQ(Pred, CmpInst::ICMP_UGE);
1833   EXPECT_EQ(RHS, APInt(32, 100));
1834 
1835   EXPECT_TRUE(ConstantRange(APInt(32, 100), APInt::getSignedMinValue(32))
1836                   .getEquivalentICmp(Pred, RHS));
1837   EXPECT_EQ(Pred, CmpInst::ICMP_SGE);
1838   EXPECT_EQ(RHS, APInt(32, 100));
1839 
1840   EXPECT_TRUE(
1841       ConstantRange(32, /*isFullSet=*/true).getEquivalentICmp(Pred, RHS));
1842   EXPECT_EQ(Pred, CmpInst::ICMP_UGE);
1843   EXPECT_EQ(RHS, APInt(32, 0));
1844 
1845   EXPECT_TRUE(
1846       ConstantRange(32, /*isFullSet=*/false).getEquivalentICmp(Pred, RHS));
1847   EXPECT_EQ(Pred, CmpInst::ICMP_ULT);
1848   EXPECT_EQ(RHS, APInt(32, 0));
1849 
1850   EXPECT_FALSE(ConstantRange(APInt(32, 100), APInt(32, 200))
1851                    .getEquivalentICmp(Pred, RHS));
1852 
1853   EXPECT_FALSE(ConstantRange(APInt::getSignedMinValue(32) - APInt(32, 100),
1854                              APInt::getSignedMinValue(32) + APInt(32, 100))
1855                    .getEquivalentICmp(Pred, RHS));
1856 
1857   EXPECT_FALSE(ConstantRange(APInt::getMinValue(32) - APInt(32, 100),
1858                              APInt::getMinValue(32) + APInt(32, 100))
1859                    .getEquivalentICmp(Pred, RHS));
1860 
1861   EXPECT_TRUE(ConstantRange(APInt(32, 100)).getEquivalentICmp(Pred, RHS));
1862   EXPECT_EQ(Pred, CmpInst::ICMP_EQ);
1863   EXPECT_EQ(RHS, APInt(32, 100));
1864 
1865   EXPECT_TRUE(
1866       ConstantRange(APInt(32, 100)).inverse().getEquivalentICmp(Pred, RHS));
1867   EXPECT_EQ(Pred, CmpInst::ICMP_NE);
1868   EXPECT_EQ(RHS, APInt(32, 100));
1869 
1870   EXPECT_TRUE(
1871       ConstantRange(APInt(512, 100)).inverse().getEquivalentICmp(Pred, RHS));
1872   EXPECT_EQ(Pred, CmpInst::ICMP_NE);
1873   EXPECT_EQ(RHS, APInt(512, 100));
1874 
1875   // NB!  It would be correct for the following four calls to getEquivalentICmp
1876   // to return ordered predicates like CmpInst::ICMP_ULT or CmpInst::ICMP_UGT.
1877   // However, that's not the case today.
1878 
1879   EXPECT_TRUE(ConstantRange(APInt(32, 0)).getEquivalentICmp(Pred, RHS));
1880   EXPECT_EQ(Pred, CmpInst::ICMP_EQ);
1881   EXPECT_EQ(RHS, APInt(32, 0));
1882 
1883   EXPECT_TRUE(
1884       ConstantRange(APInt(32, 0)).inverse().getEquivalentICmp(Pred, RHS));
1885   EXPECT_EQ(Pred, CmpInst::ICMP_NE);
1886   EXPECT_EQ(RHS, APInt(32, 0));
1887 
1888   EXPECT_TRUE(ConstantRange(APInt(32, -1)).getEquivalentICmp(Pred, RHS));
1889   EXPECT_EQ(Pred, CmpInst::ICMP_EQ);
1890   EXPECT_EQ(RHS, APInt(32, -1));
1891 
1892   EXPECT_TRUE(
1893       ConstantRange(APInt(32, -1)).inverse().getEquivalentICmp(Pred, RHS));
1894   EXPECT_EQ(Pred, CmpInst::ICMP_NE);
1895   EXPECT_EQ(RHS, APInt(32, -1));
1896 
1897   unsigned Bits = 4;
1898   EnumerateConstantRanges(Bits, [Bits](const ConstantRange &CR) {
1899     CmpInst::Predicate Pred;
1900     APInt RHS, Offset;
1901     CR.getEquivalentICmp(Pred, RHS, Offset);
1902     EnumerateAPInts(Bits, [&](const APInt &N) {
1903       bool Result = ICmpInst::compare(N + Offset, RHS, Pred);
1904       EXPECT_EQ(CR.contains(N), Result);
1905     });
1906 
1907     if (CR.getEquivalentICmp(Pred, RHS)) {
1908       EnumerateAPInts(Bits, [&](const APInt &N) {
1909         bool Result = ICmpInst::compare(N, RHS, Pred);
1910         EXPECT_EQ(CR.contains(N), Result);
1911       });
1912     }
1913   });
1914 }
1915 
1916 #define EXPECT_MAY_OVERFLOW(op) \
1917   EXPECT_EQ(ConstantRange::OverflowResult::MayOverflow, (op))
1918 #define EXPECT_ALWAYS_OVERFLOWS_LOW(op) \
1919   EXPECT_EQ(ConstantRange::OverflowResult::AlwaysOverflowsLow, (op))
1920 #define EXPECT_ALWAYS_OVERFLOWS_HIGH(op) \
1921   EXPECT_EQ(ConstantRange::OverflowResult::AlwaysOverflowsHigh, (op))
1922 #define EXPECT_NEVER_OVERFLOWS(op) \
1923   EXPECT_EQ(ConstantRange::OverflowResult::NeverOverflows, (op))
1924 
1925 TEST_F(ConstantRangeTest, UnsignedAddOverflow) {
1926   // Ill-defined - may overflow is a conservative result.
1927   EXPECT_MAY_OVERFLOW(Some.unsignedAddMayOverflow(Empty));
1928   EXPECT_MAY_OVERFLOW(Empty.unsignedAddMayOverflow(Some));
1929 
1930   // Never overflow despite one full/wrap set.
1931   ConstantRange Zero(APInt::getZero(16));
1932   EXPECT_NEVER_OVERFLOWS(Full.unsignedAddMayOverflow(Zero));
1933   EXPECT_NEVER_OVERFLOWS(Wrap.unsignedAddMayOverflow(Zero));
1934   EXPECT_NEVER_OVERFLOWS(Zero.unsignedAddMayOverflow(Full));
1935   EXPECT_NEVER_OVERFLOWS(Zero.unsignedAddMayOverflow(Wrap));
1936 
1937   // But usually full/wrap always may overflow.
1938   EXPECT_MAY_OVERFLOW(Full.unsignedAddMayOverflow(One));
1939   EXPECT_MAY_OVERFLOW(Wrap.unsignedAddMayOverflow(One));
1940   EXPECT_MAY_OVERFLOW(One.unsignedAddMayOverflow(Full));
1941   EXPECT_MAY_OVERFLOW(One.unsignedAddMayOverflow(Wrap));
1942 
1943   ConstantRange A(APInt(16, 0xfd00), APInt(16, 0xfe00));
1944   ConstantRange B1(APInt(16, 0x0100), APInt(16, 0x0201));
1945   ConstantRange B2(APInt(16, 0x0100), APInt(16, 0x0202));
1946   EXPECT_NEVER_OVERFLOWS(A.unsignedAddMayOverflow(B1));
1947   EXPECT_MAY_OVERFLOW(A.unsignedAddMayOverflow(B2));
1948   EXPECT_NEVER_OVERFLOWS(B1.unsignedAddMayOverflow(A));
1949   EXPECT_MAY_OVERFLOW(B2.unsignedAddMayOverflow(A));
1950 
1951   ConstantRange C1(APInt(16, 0x0299), APInt(16, 0x0400));
1952   ConstantRange C2(APInt(16, 0x0300), APInt(16, 0x0400));
1953   EXPECT_MAY_OVERFLOW(A.unsignedAddMayOverflow(C1));
1954   EXPECT_ALWAYS_OVERFLOWS_HIGH(A.unsignedAddMayOverflow(C2));
1955   EXPECT_MAY_OVERFLOW(C1.unsignedAddMayOverflow(A));
1956   EXPECT_ALWAYS_OVERFLOWS_HIGH(C2.unsignedAddMayOverflow(A));
1957 }
1958 
1959 TEST_F(ConstantRangeTest, UnsignedSubOverflow) {
1960   // Ill-defined - may overflow is a conservative result.
1961   EXPECT_MAY_OVERFLOW(Some.unsignedSubMayOverflow(Empty));
1962   EXPECT_MAY_OVERFLOW(Empty.unsignedSubMayOverflow(Some));
1963 
1964   // Never overflow despite one full/wrap set.
1965   ConstantRange Zero(APInt::getZero(16));
1966   ConstantRange Max(APInt::getAllOnes(16));
1967   EXPECT_NEVER_OVERFLOWS(Full.unsignedSubMayOverflow(Zero));
1968   EXPECT_NEVER_OVERFLOWS(Wrap.unsignedSubMayOverflow(Zero));
1969   EXPECT_NEVER_OVERFLOWS(Max.unsignedSubMayOverflow(Full));
1970   EXPECT_NEVER_OVERFLOWS(Max.unsignedSubMayOverflow(Wrap));
1971 
1972   // But usually full/wrap always may overflow.
1973   EXPECT_MAY_OVERFLOW(Full.unsignedSubMayOverflow(One));
1974   EXPECT_MAY_OVERFLOW(Wrap.unsignedSubMayOverflow(One));
1975   EXPECT_MAY_OVERFLOW(One.unsignedSubMayOverflow(Full));
1976   EXPECT_MAY_OVERFLOW(One.unsignedSubMayOverflow(Wrap));
1977 
1978   ConstantRange A(APInt(16, 0x0000), APInt(16, 0x0100));
1979   ConstantRange B(APInt(16, 0x0100), APInt(16, 0x0200));
1980   EXPECT_NEVER_OVERFLOWS(B.unsignedSubMayOverflow(A));
1981   EXPECT_ALWAYS_OVERFLOWS_LOW(A.unsignedSubMayOverflow(B));
1982 
1983   ConstantRange A1(APInt(16, 0x0000), APInt(16, 0x0101));
1984   ConstantRange B1(APInt(16, 0x0100), APInt(16, 0x0201));
1985   EXPECT_NEVER_OVERFLOWS(B1.unsignedSubMayOverflow(A1));
1986   EXPECT_MAY_OVERFLOW(A1.unsignedSubMayOverflow(B1));
1987 
1988   ConstantRange A2(APInt(16, 0x0000), APInt(16, 0x0102));
1989   ConstantRange B2(APInt(16, 0x0100), APInt(16, 0x0202));
1990   EXPECT_MAY_OVERFLOW(B2.unsignedSubMayOverflow(A2));
1991   EXPECT_MAY_OVERFLOW(A2.unsignedSubMayOverflow(B2));
1992 }
1993 
1994 TEST_F(ConstantRangeTest, SignedAddOverflow) {
1995   // Ill-defined - may overflow is a conservative result.
1996   EXPECT_MAY_OVERFLOW(Some.signedAddMayOverflow(Empty));
1997   EXPECT_MAY_OVERFLOW(Empty.signedAddMayOverflow(Some));
1998 
1999   // Never overflow despite one full/wrap set.
2000   ConstantRange Zero(APInt::getZero(16));
2001   EXPECT_NEVER_OVERFLOWS(Full.signedAddMayOverflow(Zero));
2002   EXPECT_NEVER_OVERFLOWS(Wrap.signedAddMayOverflow(Zero));
2003   EXPECT_NEVER_OVERFLOWS(Zero.signedAddMayOverflow(Full));
2004   EXPECT_NEVER_OVERFLOWS(Zero.signedAddMayOverflow(Wrap));
2005 
2006   // But usually full/wrap always may overflow.
2007   EXPECT_MAY_OVERFLOW(Full.signedAddMayOverflow(One));
2008   EXPECT_MAY_OVERFLOW(Wrap.signedAddMayOverflow(One));
2009   EXPECT_MAY_OVERFLOW(One.signedAddMayOverflow(Full));
2010   EXPECT_MAY_OVERFLOW(One.signedAddMayOverflow(Wrap));
2011 
2012   ConstantRange A(APInt(16, 0x7d00), APInt(16, 0x7e00));
2013   ConstantRange B1(APInt(16, 0x0100), APInt(16, 0x0201));
2014   ConstantRange B2(APInt(16, 0x0100), APInt(16, 0x0202));
2015   EXPECT_NEVER_OVERFLOWS(A.signedAddMayOverflow(B1));
2016   EXPECT_MAY_OVERFLOW(A.signedAddMayOverflow(B2));
2017   ConstantRange B3(APInt(16, 0x8000), APInt(16, 0x0201));
2018   ConstantRange B4(APInt(16, 0x8000), APInt(16, 0x0202));
2019   EXPECT_NEVER_OVERFLOWS(A.signedAddMayOverflow(B3));
2020   EXPECT_MAY_OVERFLOW(A.signedAddMayOverflow(B4));
2021   ConstantRange B5(APInt(16, 0x0299), APInt(16, 0x0400));
2022   ConstantRange B6(APInt(16, 0x0300), APInt(16, 0x0400));
2023   EXPECT_MAY_OVERFLOW(A.signedAddMayOverflow(B5));
2024   EXPECT_ALWAYS_OVERFLOWS_HIGH(A.signedAddMayOverflow(B6));
2025 
2026   ConstantRange C(APInt(16, 0x8200), APInt(16, 0x8300));
2027   ConstantRange D1(APInt(16, 0xfe00), APInt(16, 0xff00));
2028   ConstantRange D2(APInt(16, 0xfd99), APInt(16, 0xff00));
2029   EXPECT_NEVER_OVERFLOWS(C.signedAddMayOverflow(D1));
2030   EXPECT_MAY_OVERFLOW(C.signedAddMayOverflow(D2));
2031   ConstantRange D3(APInt(16, 0xfe00), APInt(16, 0x8000));
2032   ConstantRange D4(APInt(16, 0xfd99), APInt(16, 0x8000));
2033   EXPECT_NEVER_OVERFLOWS(C.signedAddMayOverflow(D3));
2034   EXPECT_MAY_OVERFLOW(C.signedAddMayOverflow(D4));
2035   ConstantRange D5(APInt(16, 0xfc00), APInt(16, 0xfd02));
2036   ConstantRange D6(APInt(16, 0xfc00), APInt(16, 0xfd01));
2037   EXPECT_MAY_OVERFLOW(C.signedAddMayOverflow(D5));
2038   EXPECT_ALWAYS_OVERFLOWS_LOW(C.signedAddMayOverflow(D6));
2039 
2040   ConstantRange E(APInt(16, 0xff00), APInt(16, 0x0100));
2041   EXPECT_NEVER_OVERFLOWS(E.signedAddMayOverflow(E));
2042   ConstantRange F(APInt(16, 0xf000), APInt(16, 0x7000));
2043   EXPECT_MAY_OVERFLOW(F.signedAddMayOverflow(F));
2044 }
2045 
2046 TEST_F(ConstantRangeTest, SignedSubOverflow) {
2047   // Ill-defined - may overflow is a conservative result.
2048   EXPECT_MAY_OVERFLOW(Some.signedSubMayOverflow(Empty));
2049   EXPECT_MAY_OVERFLOW(Empty.signedSubMayOverflow(Some));
2050 
2051   // Never overflow despite one full/wrap set.
2052   ConstantRange Zero(APInt::getZero(16));
2053   EXPECT_NEVER_OVERFLOWS(Full.signedSubMayOverflow(Zero));
2054   EXPECT_NEVER_OVERFLOWS(Wrap.signedSubMayOverflow(Zero));
2055 
2056   // But usually full/wrap always may overflow.
2057   EXPECT_MAY_OVERFLOW(Full.signedSubMayOverflow(One));
2058   EXPECT_MAY_OVERFLOW(Wrap.signedSubMayOverflow(One));
2059   EXPECT_MAY_OVERFLOW(One.signedSubMayOverflow(Full));
2060   EXPECT_MAY_OVERFLOW(One.signedSubMayOverflow(Wrap));
2061 
2062   ConstantRange A(APInt(16, 0x7d00), APInt(16, 0x7e00));
2063   ConstantRange B1(APInt(16, 0xfe00), APInt(16, 0xff00));
2064   ConstantRange B2(APInt(16, 0xfd99), APInt(16, 0xff00));
2065   EXPECT_NEVER_OVERFLOWS(A.signedSubMayOverflow(B1));
2066   EXPECT_MAY_OVERFLOW(A.signedSubMayOverflow(B2));
2067   ConstantRange B3(APInt(16, 0xfc00), APInt(16, 0xfd02));
2068   ConstantRange B4(APInt(16, 0xfc00), APInt(16, 0xfd01));
2069   EXPECT_MAY_OVERFLOW(A.signedSubMayOverflow(B3));
2070   EXPECT_ALWAYS_OVERFLOWS_HIGH(A.signedSubMayOverflow(B4));
2071 
2072   ConstantRange C(APInt(16, 0x8200), APInt(16, 0x8300));
2073   ConstantRange D1(APInt(16, 0x0100), APInt(16, 0x0201));
2074   ConstantRange D2(APInt(16, 0x0100), APInt(16, 0x0202));
2075   EXPECT_NEVER_OVERFLOWS(C.signedSubMayOverflow(D1));
2076   EXPECT_MAY_OVERFLOW(C.signedSubMayOverflow(D2));
2077   ConstantRange D3(APInt(16, 0x0299), APInt(16, 0x0400));
2078   ConstantRange D4(APInt(16, 0x0300), APInt(16, 0x0400));
2079   EXPECT_MAY_OVERFLOW(C.signedSubMayOverflow(D3));
2080   EXPECT_ALWAYS_OVERFLOWS_LOW(C.signedSubMayOverflow(D4));
2081 
2082   ConstantRange E(APInt(16, 0xff00), APInt(16, 0x0100));
2083   EXPECT_NEVER_OVERFLOWS(E.signedSubMayOverflow(E));
2084   ConstantRange F(APInt(16, 0xf000), APInt(16, 0x7001));
2085   EXPECT_MAY_OVERFLOW(F.signedSubMayOverflow(F));
2086 }
2087 
2088 template<typename Fn1, typename Fn2>
2089 static void TestOverflowExhaustive(Fn1 OverflowFn, Fn2 MayOverflowFn) {
2090   // Constant range overflow checks are tested exhaustively on 4-bit numbers.
2091   unsigned Bits = 4;
2092   EnumerateTwoConstantRanges(Bits, [=](const ConstantRange &CR1,
2093                                        const ConstantRange &CR2) {
2094     // Loop over all N1 in CR1 and N2 in CR2 and check whether any of the
2095     // operations have overflow / have no overflow.
2096     bool RangeHasOverflowLow = false;
2097     bool RangeHasOverflowHigh = false;
2098     bool RangeHasNoOverflow = false;
2099     ForeachNumInConstantRange(CR1, [&](const APInt &N1) {
2100       ForeachNumInConstantRange(CR2, [&](const APInt &N2) {
2101         bool IsOverflowHigh;
2102         if (!OverflowFn(IsOverflowHigh, N1, N2)) {
2103           RangeHasNoOverflow = true;
2104           return;
2105         }
2106 
2107         if (IsOverflowHigh)
2108           RangeHasOverflowHigh = true;
2109         else
2110           RangeHasOverflowLow = true;
2111       });
2112     });
2113 
2114     ConstantRange::OverflowResult OR = MayOverflowFn(CR1, CR2);
2115     switch (OR) {
2116     case ConstantRange::OverflowResult::AlwaysOverflowsLow:
2117       EXPECT_TRUE(RangeHasOverflowLow);
2118       EXPECT_FALSE(RangeHasOverflowHigh);
2119       EXPECT_FALSE(RangeHasNoOverflow);
2120       break;
2121     case ConstantRange::OverflowResult::AlwaysOverflowsHigh:
2122       EXPECT_TRUE(RangeHasOverflowHigh);
2123       EXPECT_FALSE(RangeHasOverflowLow);
2124       EXPECT_FALSE(RangeHasNoOverflow);
2125       break;
2126     case ConstantRange::OverflowResult::NeverOverflows:
2127       EXPECT_FALSE(RangeHasOverflowLow);
2128       EXPECT_FALSE(RangeHasOverflowHigh);
2129       EXPECT_TRUE(RangeHasNoOverflow);
2130       break;
2131     case ConstantRange::OverflowResult::MayOverflow:
2132       // We return MayOverflow for empty sets as a conservative result,
2133       // but of course neither the RangeHasOverflow nor the
2134       // RangeHasNoOverflow flags will be set.
2135       if (CR1.isEmptySet() || CR2.isEmptySet())
2136         break;
2137 
2138       EXPECT_TRUE(RangeHasOverflowLow || RangeHasOverflowHigh);
2139       EXPECT_TRUE(RangeHasNoOverflow);
2140       break;
2141     }
2142   });
2143 }
2144 
2145 TEST_F(ConstantRangeTest, UnsignedAddOverflowExhaustive) {
2146   TestOverflowExhaustive(
2147       [](bool &IsOverflowHigh, const APInt &N1, const APInt &N2) {
2148         bool Overflow;
2149         (void) N1.uadd_ov(N2, Overflow);
2150         IsOverflowHigh = true;
2151         return Overflow;
2152       },
2153       [](const ConstantRange &CR1, const ConstantRange &CR2) {
2154         return CR1.unsignedAddMayOverflow(CR2);
2155       });
2156 }
2157 
2158 TEST_F(ConstantRangeTest, UnsignedSubOverflowExhaustive) {
2159   TestOverflowExhaustive(
2160       [](bool &IsOverflowHigh, const APInt &N1, const APInt &N2) {
2161         bool Overflow;
2162         (void) N1.usub_ov(N2, Overflow);
2163         IsOverflowHigh = false;
2164         return Overflow;
2165       },
2166       [](const ConstantRange &CR1, const ConstantRange &CR2) {
2167         return CR1.unsignedSubMayOverflow(CR2);
2168       });
2169 }
2170 
2171 TEST_F(ConstantRangeTest, UnsignedMulOverflowExhaustive) {
2172   TestOverflowExhaustive(
2173       [](bool &IsOverflowHigh, const APInt &N1, const APInt &N2) {
2174         bool Overflow;
2175         (void) N1.umul_ov(N2, Overflow);
2176         IsOverflowHigh = true;
2177         return Overflow;
2178       },
2179       [](const ConstantRange &CR1, const ConstantRange &CR2) {
2180         return CR1.unsignedMulMayOverflow(CR2);
2181       });
2182 }
2183 
2184 TEST_F(ConstantRangeTest, SignedAddOverflowExhaustive) {
2185   TestOverflowExhaustive(
2186       [](bool &IsOverflowHigh, const APInt &N1, const APInt &N2) {
2187         bool Overflow;
2188         (void) N1.sadd_ov(N2, Overflow);
2189         IsOverflowHigh = N1.isNonNegative();
2190         return Overflow;
2191       },
2192       [](const ConstantRange &CR1, const ConstantRange &CR2) {
2193         return CR1.signedAddMayOverflow(CR2);
2194       });
2195 }
2196 
2197 TEST_F(ConstantRangeTest, SignedSubOverflowExhaustive) {
2198   TestOverflowExhaustive(
2199       [](bool &IsOverflowHigh, const APInt &N1, const APInt &N2) {
2200         bool Overflow;
2201         (void) N1.ssub_ov(N2, Overflow);
2202         IsOverflowHigh = N1.isNonNegative();
2203         return Overflow;
2204       },
2205       [](const ConstantRange &CR1, const ConstantRange &CR2) {
2206         return CR1.signedSubMayOverflow(CR2);
2207       });
2208 }
2209 
2210 TEST_F(ConstantRangeTest, FromKnownBits) {
2211   KnownBits Unknown(16);
2212   EXPECT_EQ(Full, ConstantRange::fromKnownBits(Unknown, /*signed*/false));
2213   EXPECT_EQ(Full, ConstantRange::fromKnownBits(Unknown, /*signed*/true));
2214 
2215   // .10..01. -> unsigned 01000010 (66)  to 11011011 (219)
2216   //          -> signed   11000010 (194) to 01011011 (91)
2217   KnownBits Known(8);
2218   Known.Zero = 36;
2219   Known.One = 66;
2220   ConstantRange Unsigned(APInt(8, 66), APInt(8, 219 + 1));
2221   ConstantRange Signed(APInt(8, 194), APInt(8, 91 + 1));
2222   EXPECT_EQ(Unsigned, ConstantRange::fromKnownBits(Known, /*signed*/false));
2223   EXPECT_EQ(Signed, ConstantRange::fromKnownBits(Known, /*signed*/true));
2224 
2225   // 1.10.10. -> 10100100 (164) to 11101101 (237)
2226   Known.Zero = 18;
2227   Known.One = 164;
2228   ConstantRange CR1(APInt(8, 164), APInt(8, 237 + 1));
2229   EXPECT_EQ(CR1, ConstantRange::fromKnownBits(Known, /*signed*/false));
2230   EXPECT_EQ(CR1, ConstantRange::fromKnownBits(Known, /*signed*/true));
2231 
2232   // 01.0.1.0 -> 01000100 (68) to 01101110 (110)
2233   Known.Zero = 145;
2234   Known.One = 68;
2235   ConstantRange CR2(APInt(8, 68), APInt(8, 110 + 1));
2236   EXPECT_EQ(CR2, ConstantRange::fromKnownBits(Known, /*signed*/false));
2237   EXPECT_EQ(CR2, ConstantRange::fromKnownBits(Known, /*signed*/true));
2238 }
2239 
2240 TEST_F(ConstantRangeTest, FromKnownBitsExhaustive) {
2241   unsigned Bits = 4;
2242   unsigned Max = 1 << Bits;
2243   KnownBits Known(Bits);
2244   for (unsigned Zero = 0; Zero < Max; ++Zero) {
2245     for (unsigned One = 0; One < Max; ++One) {
2246       Known.Zero = Zero;
2247       Known.One = One;
2248       if (Known.hasConflict() || Known.isUnknown())
2249         continue;
2250 
2251       SmallBitVector Elems(1 << Bits);
2252       for (unsigned N = 0; N < Max; ++N) {
2253         APInt Num(Bits, N);
2254         if ((Num & Known.Zero) != 0 || (~Num & Known.One) != 0)
2255           continue;
2256         Elems.set(Num.getZExtValue());
2257       }
2258 
2259       TestRange(ConstantRange::fromKnownBits(Known, false),
2260                 Elems, PreferSmallestUnsigned, {});
2261       TestRange(ConstantRange::fromKnownBits(Known, true),
2262                 Elems, PreferSmallestSigned, {});
2263     }
2264   }
2265 }
2266 
2267 TEST_F(ConstantRangeTest, ToKnownBits) {
2268   unsigned Bits = 4;
2269   EnumerateConstantRanges(Bits, [&](const ConstantRange &CR) {
2270     KnownBits Known = CR.toKnownBits();
2271     KnownBits ExpectedKnown(Bits);
2272     ExpectedKnown.Zero.setAllBits();
2273     ExpectedKnown.One.setAllBits();
2274     ForeachNumInConstantRange(CR, [&](const APInt &N) {
2275       ExpectedKnown.One &= N;
2276       ExpectedKnown.Zero &= ~N;
2277     });
2278     // For an empty CR any result would be legal.
2279     if (!CR.isEmptySet()) {
2280       EXPECT_EQ(ExpectedKnown, Known);
2281     }
2282   });
2283 }
2284 
2285 TEST_F(ConstantRangeTest, Negative) {
2286   // All elements in an empty set (of which there are none) are both negative
2287   // and non-negative. Empty & full sets checked explicitly for clarity, but
2288   // they are also covered by the exhaustive test below.
2289   EXPECT_TRUE(Empty.isAllNegative());
2290   EXPECT_TRUE(Empty.isAllNonNegative());
2291   EXPECT_FALSE(Full.isAllNegative());
2292   EXPECT_FALSE(Full.isAllNonNegative());
2293 
2294   unsigned Bits = 4;
2295   EnumerateConstantRanges(Bits, [](const ConstantRange &CR) {
2296     bool AllNegative = true;
2297     bool AllNonNegative = true;
2298     ForeachNumInConstantRange(CR, [&](const APInt &N) {
2299       if (!N.isNegative())
2300         AllNegative = false;
2301       if (!N.isNonNegative())
2302         AllNonNegative = false;
2303     });
2304     assert((CR.isEmptySet() || !AllNegative || !AllNonNegative) &&
2305            "Only empty set can be both all negative and all non-negative");
2306 
2307     EXPECT_EQ(AllNegative, CR.isAllNegative());
2308     EXPECT_EQ(AllNonNegative, CR.isAllNonNegative());
2309   });
2310 }
2311 
2312 TEST_F(ConstantRangeTest, UAddSat) {
2313   TestBinaryOpExhaustive(
2314       [](const ConstantRange &CR1, const ConstantRange &CR2) {
2315         return CR1.uadd_sat(CR2);
2316       },
2317       [](const APInt &N1, const APInt &N2) {
2318         return N1.uadd_sat(N2);
2319       },
2320       PreferSmallestUnsigned);
2321 }
2322 
2323 TEST_F(ConstantRangeTest, USubSat) {
2324   TestBinaryOpExhaustive(
2325       [](const ConstantRange &CR1, const ConstantRange &CR2) {
2326         return CR1.usub_sat(CR2);
2327       },
2328       [](const APInt &N1, const APInt &N2) {
2329         return N1.usub_sat(N2);
2330       },
2331       PreferSmallestUnsigned);
2332 }
2333 
2334 TEST_F(ConstantRangeTest, UMulSat) {
2335   TestBinaryOpExhaustive(
2336       [](const ConstantRange &CR1, const ConstantRange &CR2) {
2337         return CR1.umul_sat(CR2);
2338       },
2339       [](const APInt &N1, const APInt &N2) { return N1.umul_sat(N2); },
2340       PreferSmallestUnsigned);
2341 }
2342 
2343 TEST_F(ConstantRangeTest, UShlSat) {
2344   TestBinaryOpExhaustive(
2345       [](const ConstantRange &CR1, const ConstantRange &CR2) {
2346         return CR1.ushl_sat(CR2);
2347       },
2348       [](const APInt &N1, const APInt &N2) { return N1.ushl_sat(N2); },
2349       PreferSmallestUnsigned);
2350 }
2351 
2352 TEST_F(ConstantRangeTest, SAddSat) {
2353   TestBinaryOpExhaustive(
2354       [](const ConstantRange &CR1, const ConstantRange &CR2) {
2355         return CR1.sadd_sat(CR2);
2356       },
2357       [](const APInt &N1, const APInt &N2) {
2358         return N1.sadd_sat(N2);
2359       },
2360       PreferSmallestSigned);
2361 }
2362 
2363 TEST_F(ConstantRangeTest, SSubSat) {
2364   TestBinaryOpExhaustive(
2365       [](const ConstantRange &CR1, const ConstantRange &CR2) {
2366         return CR1.ssub_sat(CR2);
2367       },
2368       [](const APInt &N1, const APInt &N2) {
2369         return N1.ssub_sat(N2);
2370       },
2371       PreferSmallestSigned);
2372 }
2373 
2374 TEST_F(ConstantRangeTest, SMulSat) {
2375   TestBinaryOpExhaustive(
2376       [](const ConstantRange &CR1, const ConstantRange &CR2) {
2377         return CR1.smul_sat(CR2);
2378       },
2379       [](const APInt &N1, const APInt &N2) { return N1.smul_sat(N2); },
2380       PreferSmallestSigned);
2381 }
2382 
2383 TEST_F(ConstantRangeTest, SShlSat) {
2384   TestBinaryOpExhaustive(
2385       [](const ConstantRange &CR1, const ConstantRange &CR2) {
2386         return CR1.sshl_sat(CR2);
2387       },
2388       [](const APInt &N1, const APInt &N2) { return N1.sshl_sat(N2); },
2389       PreferSmallestSigned);
2390 }
2391 
2392 TEST_F(ConstantRangeTest, Abs) {
2393   TestUnaryOpExhaustive(
2394       [](const ConstantRange &CR) { return CR.abs(); },
2395       [](const APInt &N) { return N.abs(); });
2396 
2397   TestUnaryOpExhaustive(
2398       [](const ConstantRange &CR) { return CR.abs(/*IntMinIsPoison=*/true); },
2399       [](const APInt &N) -> Optional<APInt> {
2400         if (N.isMinSignedValue())
2401           return std::nullopt;
2402         return N.abs();
2403       });
2404 }
2405 
2406 TEST_F(ConstantRangeTest, castOps) {
2407   ConstantRange A(APInt(16, 66), APInt(16, 128));
2408   ConstantRange FpToI8 = A.castOp(Instruction::FPToSI, 8);
2409   EXPECT_EQ(8u, FpToI8.getBitWidth());
2410   EXPECT_TRUE(FpToI8.isFullSet());
2411 
2412   ConstantRange FpToI16 = A.castOp(Instruction::FPToSI, 16);
2413   EXPECT_EQ(16u, FpToI16.getBitWidth());
2414   EXPECT_EQ(A, FpToI16);
2415 
2416   ConstantRange FPExtToDouble = A.castOp(Instruction::FPExt, 64);
2417   EXPECT_EQ(64u, FPExtToDouble.getBitWidth());
2418   EXPECT_TRUE(FPExtToDouble.isFullSet());
2419 
2420   ConstantRange PtrToInt = A.castOp(Instruction::PtrToInt, 64);
2421   EXPECT_EQ(64u, PtrToInt.getBitWidth());
2422   EXPECT_TRUE(PtrToInt.isFullSet());
2423 
2424   ConstantRange IntToPtr = A.castOp(Instruction::IntToPtr, 64);
2425   EXPECT_EQ(64u, IntToPtr.getBitWidth());
2426   EXPECT_TRUE(IntToPtr.isFullSet());
2427 }
2428 
2429 TEST_F(ConstantRangeTest, binaryAnd) {
2430   // Single element ranges.
2431   ConstantRange R16(APInt(8, 16));
2432   ConstantRange R20(APInt(8, 20));
2433   EXPECT_EQ(*R16.binaryAnd(R16).getSingleElement(), APInt(8, 16));
2434   EXPECT_EQ(*R16.binaryAnd(R20).getSingleElement(), APInt(8, 16 & 20));
2435 
2436   ConstantRange R16_32(APInt(8, 16), APInt(8, 32));
2437   // 'And' with a high bits mask.
2438   ConstantRange R32(APInt(8, 32));
2439   EXPECT_TRUE(R16_32.binaryAnd(R32).getSingleElement()->isZero());
2440   EXPECT_TRUE(R32.binaryAnd(R16_32).getSingleElement()->isZero());
2441   // 'And' with a low bits mask. Handled conservatively for now.
2442   ConstantRange R4(APInt(8, 4));
2443   ConstantRange R0_5(APInt(8, 0), APInt(8, 5));
2444   EXPECT_EQ(R16_32.binaryAnd(R4), R0_5);
2445   EXPECT_EQ(R4.binaryAnd(R16_32), R0_5);
2446 
2447   // Ranges with more than one element. Handled conservatively for now.
2448   ConstantRange R0_99(APInt(8, 0), APInt(8, 99));
2449   ConstantRange R0_32(APInt(8, 0), APInt(8, 32));
2450   EXPECT_EQ(R16_32.binaryAnd(R0_99), R0_32);
2451   EXPECT_EQ(R0_99.binaryAnd(R16_32), R0_32);
2452 
2453   TestBinaryOpExhaustive(
2454       [](const ConstantRange &CR1, const ConstantRange &CR2) {
2455         return CR1.binaryAnd(CR2);
2456       },
2457       [](const APInt &N1, const APInt &N2) { return N1 & N2; }, PreferSmallest,
2458       CheckSingleElementsOnly);
2459 }
2460 
2461 TEST_F(ConstantRangeTest, binaryOr) {
2462   // Single element ranges.
2463   ConstantRange R16(APInt(8, 16));
2464   ConstantRange R20(APInt(8, 20));
2465   EXPECT_EQ(*R16.binaryOr(R16).getSingleElement(), APInt(8, 16));
2466   EXPECT_EQ(*R16.binaryOr(R20).getSingleElement(), APInt(8, 16 | 20));
2467 
2468   ConstantRange R16_32(APInt(8, 16), APInt(8, 32));
2469   // 'Or' with a high bits mask.
2470   // KnownBits estimate is important, otherwise the maximum included element
2471   // would be 2^8 - 1.
2472   ConstantRange R32(APInt(8, 32));
2473   ConstantRange R48_64(APInt(8, 48), APInt(8, 64));
2474   EXPECT_EQ(R16_32.binaryOr(R32), R48_64);
2475   EXPECT_EQ(R32.binaryOr(R16_32), R48_64);
2476   // 'Or' with a low bits mask.
2477   ConstantRange R4(APInt(8, 4));
2478   ConstantRange R0_16(APInt(8, 0), APInt(8, 16));
2479   ConstantRange R4_16(APInt(8, 4), APInt(8, 16));
2480   EXPECT_EQ(R0_16.binaryOr(R4), R4_16);
2481   EXPECT_EQ(R4.binaryOr(R0_16), R4_16);
2482 
2483   // Ranges with more than one element. Handled conservatively for now.
2484   // UMaxUMin estimate is important, otherwise the lower bound would be zero.
2485   ConstantRange R0_64(APInt(8, 0), APInt(8, 64));
2486   ConstantRange R5_32(APInt(8, 5), APInt(8, 32));
2487   ConstantRange R5_64(APInt(8, 5), APInt(8, 64));
2488   EXPECT_EQ(R0_64.binaryOr(R5_32), R5_64);
2489   EXPECT_EQ(R5_32.binaryOr(R0_64), R5_64);
2490 
2491   TestBinaryOpExhaustive(
2492       [](const ConstantRange &CR1, const ConstantRange &CR2) {
2493         return CR1.binaryOr(CR2);
2494       },
2495       [](const APInt &N1, const APInt &N2) { return N1 | N2; }, PreferSmallest,
2496       CheckSingleElementsOnly);
2497 }
2498 
2499 TEST_F(ConstantRangeTest, binaryXor) {
2500   // Single element ranges.
2501   ConstantRange R16(APInt(8, 16));
2502   ConstantRange R20(APInt(8, 20));
2503   EXPECT_EQ(*R16.binaryXor(R16).getSingleElement(), APInt(8, 0));
2504   EXPECT_EQ(*R16.binaryXor(R20).getSingleElement(), APInt(8, 16 ^ 20));
2505 
2506   // Ranges with more than a single element.
2507   ConstantRange R16_35(APInt(8, 16), APInt(8, 35));
2508   ConstantRange R0_99(APInt(8, 0), APInt(8, 99));
2509   EXPECT_EQ(R16_35.binaryXor(R16_35), ConstantRange(APInt(8, 0), APInt(8, 64)));
2510   EXPECT_EQ(R16_35.binaryXor(R0_99), ConstantRange(APInt(8, 0), APInt(8, 128)));
2511   EXPECT_EQ(R0_99.binaryXor(R16_35), ConstantRange(APInt(8, 0), APInt(8, 128)));
2512 
2513   TestBinaryOpExhaustive(
2514       [](const ConstantRange &CR1, const ConstantRange &CR2) {
2515         return CR1.binaryXor(CR2);
2516       },
2517       [](const APInt &N1, const APInt &N2) {
2518         return N1 ^ N2;
2519       },
2520       PreferSmallest,
2521       CheckSingleElementsOnly);
2522 }
2523 
2524 TEST_F(ConstantRangeTest, binaryNot) {
2525   TestUnaryOpExhaustive(
2526       [](const ConstantRange &CR) { return CR.binaryNot(); },
2527       [](const APInt &N) { return ~N; },
2528       PreferSmallest);
2529   TestUnaryOpExhaustive(
2530       [](const ConstantRange &CR) {
2531         return CR.binaryXor(ConstantRange(APInt::getAllOnes(CR.getBitWidth())));
2532       },
2533       [](const APInt &N) { return ~N; }, PreferSmallest);
2534   TestUnaryOpExhaustive(
2535       [](const ConstantRange &CR) {
2536         return ConstantRange(APInt::getAllOnes(CR.getBitWidth())).binaryXor(CR);
2537       },
2538       [](const APInt &N) { return ~N; }, PreferSmallest);
2539 }
2540 
2541 template <typename T>
2542 void testConstantRangeICmpPredEquivalence(ICmpInst::Predicate SrcPred, T Func) {
2543   unsigned Bits = 4;
2544   EnumerateTwoConstantRanges(
2545       Bits, [&](const ConstantRange &CR1, const ConstantRange &CR2) {
2546         ICmpInst::Predicate TgtPred;
2547         bool ExpectedEquivalent;
2548         std::tie(TgtPred, ExpectedEquivalent) = Func(CR1, CR2);
2549         if (TgtPred == CmpInst::Predicate::BAD_ICMP_PREDICATE)
2550           return;
2551         bool TrulyEquivalent = true;
2552         ForeachNumInConstantRange(CR1, [&](const APInt &N1) {
2553           if (!TrulyEquivalent)
2554             return;
2555           ForeachNumInConstantRange(CR2, [&](const APInt &N2) {
2556             if (!TrulyEquivalent)
2557               return;
2558             TrulyEquivalent &= ICmpInst::compare(N1, N2, SrcPred) ==
2559                                ICmpInst::compare(N1, N2, TgtPred);
2560           });
2561         });
2562         ASSERT_EQ(TrulyEquivalent, ExpectedEquivalent);
2563       });
2564 }
2565 
2566 TEST_F(ConstantRangeTest, areInsensitiveToSignednessOfICmpPredicate) {
2567   for (auto Pred : ICmpInst::predicates()) {
2568     if (ICmpInst::isEquality(Pred))
2569       continue;
2570     ICmpInst::Predicate FlippedSignednessPred =
2571         ICmpInst::getFlippedSignednessPredicate(Pred);
2572     testConstantRangeICmpPredEquivalence(Pred, [FlippedSignednessPred](
2573                                                    const ConstantRange &CR1,
2574                                                    const ConstantRange &CR2) {
2575       return std::make_pair(
2576           FlippedSignednessPred,
2577           ConstantRange::areInsensitiveToSignednessOfICmpPredicate(CR1, CR2));
2578     });
2579   }
2580 }
2581 
2582 TEST_F(ConstantRangeTest, areInsensitiveToSignednessOfInvertedICmpPredicate) {
2583   for (auto Pred : ICmpInst::predicates()) {
2584     if (ICmpInst::isEquality(Pred))
2585       continue;
2586     ICmpInst::Predicate InvertedFlippedSignednessPred =
2587         ICmpInst::getInversePredicate(
2588             ICmpInst::getFlippedSignednessPredicate(Pred));
2589     testConstantRangeICmpPredEquivalence(
2590         Pred, [InvertedFlippedSignednessPred](const ConstantRange &CR1,
2591                                               const ConstantRange &CR2) {
2592           return std::make_pair(
2593               InvertedFlippedSignednessPred,
2594               ConstantRange::areInsensitiveToSignednessOfInvertedICmpPredicate(
2595                   CR1, CR2));
2596         });
2597   }
2598 }
2599 
2600 TEST_F(ConstantRangeTest, getEquivalentPredWithFlippedSignedness) {
2601   for (auto Pred : ICmpInst::predicates()) {
2602     if (ICmpInst::isEquality(Pred))
2603       continue;
2604     testConstantRangeICmpPredEquivalence(
2605         Pred, [Pred](const ConstantRange &CR1, const ConstantRange &CR2) {
2606           return std::make_pair(
2607               ConstantRange::getEquivalentPredWithFlippedSignedness(Pred, CR1,
2608                                                                     CR2),
2609               /*ExpectedEquivalent=*/true);
2610         });
2611   }
2612 }
2613 
2614 TEST_F(ConstantRangeTest, isSizeLargerThan) {
2615   EXPECT_FALSE(Empty.isSizeLargerThan(0));
2616 
2617   EXPECT_TRUE(Full.isSizeLargerThan(0));
2618   EXPECT_TRUE(Full.isSizeLargerThan(65535));
2619   EXPECT_FALSE(Full.isSizeLargerThan(65536));
2620 
2621   EXPECT_TRUE(One.isSizeLargerThan(0));
2622   EXPECT_FALSE(One.isSizeLargerThan(1));
2623 }
2624 
2625 } // anonymous namespace
2626