xref: /llvm-project/llvm/unittests/Analysis/ValueTrackingTest.cpp (revision 7a46baa465c49db84b7b5f8fa9ab847ec1da3ce4)
1 //===- ValueTrackingTest.cpp - ValueTracking 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/Analysis/ValueTracking.h"
10 #include "llvm/Analysis/AssumptionCache.h"
11 #include "llvm/AsmParser/Parser.h"
12 #include "llvm/IR/ConstantRange.h"
13 #include "llvm/IR/Dominators.h"
14 #include "llvm/IR/Function.h"
15 #include "llvm/IR/IRBuilder.h"
16 #include "llvm/IR/InstIterator.h"
17 #include "llvm/IR/Instructions.h"
18 #include "llvm/IR/LLVMContext.h"
19 #include "llvm/IR/Module.h"
20 #include "llvm/Support/ErrorHandling.h"
21 #include "llvm/Support/KnownBits.h"
22 #include "llvm/Support/SourceMgr.h"
23 #include "llvm/Transforms/Utils/Local.h"
24 #include "gtest/gtest.h"
25 
26 using namespace llvm;
27 
28 namespace {
29 
30 static Instruction *findInstructionByNameOrNull(Function *F, StringRef Name) {
31   for (Instruction &I : instructions(F))
32     if (I.getName() == Name)
33       return &I;
34 
35   return nullptr;
36 }
37 
38 static Instruction &findInstructionByName(Function *F, StringRef Name) {
39   auto *I = findInstructionByNameOrNull(F, Name);
40   if (I)
41     return *I;
42 
43   llvm_unreachable("Expected value not found");
44 }
45 
46 class ValueTrackingTest : public testing::Test {
47 protected:
48   std::unique_ptr<Module> parseModule(StringRef Assembly) {
49     SMDiagnostic Error;
50     std::unique_ptr<Module> M = parseAssemblyString(Assembly, Error, Context);
51 
52     std::string errMsg;
53     raw_string_ostream os(errMsg);
54     Error.print("", os);
55     EXPECT_TRUE(M) << os.str();
56 
57     return M;
58   }
59 
60   void parseAssembly(StringRef Assembly) {
61     M = parseModule(Assembly);
62     ASSERT_TRUE(M);
63 
64     F = M->getFunction("test");
65     ASSERT_TRUE(F) << "Test must have a function @test";
66     if (!F)
67       return;
68 
69     A = findInstructionByNameOrNull(F, "A");
70     ASSERT_TRUE(A) << "@test must have an instruction %A";
71     A2 = findInstructionByNameOrNull(F, "A2");
72     A3 = findInstructionByNameOrNull(F, "A3");
73     A4 = findInstructionByNameOrNull(F, "A4");
74     A5 = findInstructionByNameOrNull(F, "A5");
75     A6 = findInstructionByNameOrNull(F, "A6");
76     A7 = findInstructionByNameOrNull(F, "A7");
77 
78     CxtI = findInstructionByNameOrNull(F, "CxtI");
79     CxtI2 = findInstructionByNameOrNull(F, "CxtI2");
80     CxtI3 = findInstructionByNameOrNull(F, "CxtI3");
81   }
82 
83   LLVMContext Context;
84   std::unique_ptr<Module> M;
85   Function *F = nullptr;
86   Instruction *A = nullptr;
87   // Instructions (optional)
88   Instruction *A2 = nullptr, *A3 = nullptr, *A4 = nullptr, *A5 = nullptr,
89               *A6 = nullptr, *A7 = nullptr;
90 
91   // Context instructions (optional)
92   Instruction *CxtI = nullptr, *CxtI2 = nullptr, *CxtI3 = nullptr;
93 };
94 
95 class MatchSelectPatternTest : public ValueTrackingTest {
96 protected:
97   void expectPattern(const SelectPatternResult &P) {
98     Value *LHS, *RHS;
99     Instruction::CastOps CastOp;
100     SelectPatternResult R = matchSelectPattern(A, LHS, RHS, &CastOp);
101     EXPECT_EQ(P.Flavor, R.Flavor);
102     EXPECT_EQ(P.NaNBehavior, R.NaNBehavior);
103     EXPECT_EQ(P.Ordered, R.Ordered);
104   }
105 };
106 
107 class ComputeKnownBitsTest : public ValueTrackingTest {
108 protected:
109   void expectKnownBits(uint64_t Zero, uint64_t One) {
110     auto Known = computeKnownBits(A, M->getDataLayout());
111     ASSERT_FALSE(Known.hasConflict());
112     EXPECT_EQ(Known.One.getZExtValue(), One);
113     EXPECT_EQ(Known.Zero.getZExtValue(), Zero);
114   }
115 };
116 
117 class ComputeKnownFPClassTest : public ValueTrackingTest {
118 protected:
119   void expectKnownFPClass(unsigned KnownTrue, std::optional<bool> SignBitKnown,
120                           Instruction *TestVal = nullptr) {
121     if (!TestVal)
122       TestVal = A;
123 
124     KnownFPClass Known = computeKnownFPClass(TestVal, M->getDataLayout());
125     EXPECT_EQ(KnownTrue, Known.KnownFPClasses);
126     EXPECT_EQ(SignBitKnown, Known.SignBit);
127   }
128 };
129 }
130 
131 TEST_F(MatchSelectPatternTest, SimpleFMin) {
132   parseAssembly(
133       "define float @test(float %a) {\n"
134       "  %1 = fcmp ult float %a, 5.0\n"
135       "  %A = select i1 %1, float %a, float 5.0\n"
136       "  ret float %A\n"
137       "}\n");
138   expectPattern({SPF_FMINNUM, SPNB_RETURNS_NAN, false});
139 }
140 
141 TEST_F(MatchSelectPatternTest, SimpleFMax) {
142   parseAssembly(
143       "define float @test(float %a) {\n"
144       "  %1 = fcmp ogt float %a, 5.0\n"
145       "  %A = select i1 %1, float %a, float 5.0\n"
146       "  ret float %A\n"
147       "}\n");
148   expectPattern({SPF_FMAXNUM, SPNB_RETURNS_OTHER, true});
149 }
150 
151 TEST_F(MatchSelectPatternTest, SwappedFMax) {
152   parseAssembly(
153       "define float @test(float %a) {\n"
154       "  %1 = fcmp olt float 5.0, %a\n"
155       "  %A = select i1 %1, float %a, float 5.0\n"
156       "  ret float %A\n"
157       "}\n");
158   expectPattern({SPF_FMAXNUM, SPNB_RETURNS_OTHER, false});
159 }
160 
161 TEST_F(MatchSelectPatternTest, SwappedFMax2) {
162   parseAssembly(
163       "define float @test(float %a) {\n"
164       "  %1 = fcmp olt float %a, 5.0\n"
165       "  %A = select i1 %1, float 5.0, float %a\n"
166       "  ret float %A\n"
167       "}\n");
168   expectPattern({SPF_FMAXNUM, SPNB_RETURNS_NAN, false});
169 }
170 
171 TEST_F(MatchSelectPatternTest, SwappedFMax3) {
172   parseAssembly(
173       "define float @test(float %a) {\n"
174       "  %1 = fcmp ult float %a, 5.0\n"
175       "  %A = select i1 %1, float 5.0, float %a\n"
176       "  ret float %A\n"
177       "}\n");
178   expectPattern({SPF_FMAXNUM, SPNB_RETURNS_OTHER, true});
179 }
180 
181 TEST_F(MatchSelectPatternTest, FastFMin) {
182   parseAssembly(
183       "define float @test(float %a) {\n"
184       "  %1 = fcmp nnan olt float %a, 5.0\n"
185       "  %A = select i1 %1, float %a, float 5.0\n"
186       "  ret float %A\n"
187       "}\n");
188   expectPattern({SPF_FMINNUM, SPNB_RETURNS_ANY, false});
189 }
190 
191 TEST_F(MatchSelectPatternTest, FMinConstantZero) {
192   parseAssembly(
193       "define float @test(float %a) {\n"
194       "  %1 = fcmp ole float %a, 0.0\n"
195       "  %A = select i1 %1, float %a, float 0.0\n"
196       "  ret float %A\n"
197       "}\n");
198   // This shouldn't be matched, as %a could be -0.0.
199   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
200 }
201 
202 TEST_F(MatchSelectPatternTest, FMinConstantZeroNsz) {
203   parseAssembly(
204       "define float @test(float %a) {\n"
205       "  %1 = fcmp nsz ole float %a, 0.0\n"
206       "  %A = select i1 %1, float %a, float 0.0\n"
207       "  ret float %A\n"
208       "}\n");
209   // But this should be, because we've ignored signed zeroes.
210   expectPattern({SPF_FMINNUM, SPNB_RETURNS_OTHER, true});
211 }
212 
213 TEST_F(MatchSelectPatternTest, FMinMismatchConstantZero1) {
214   parseAssembly(
215       "define float @test(float %a) {\n"
216       "  %1 = fcmp olt float -0.0, %a\n"
217       "  %A = select i1 %1, float 0.0, float %a\n"
218       "  ret float %A\n"
219       "}\n");
220   // The sign of zero doesn't matter in fcmp.
221   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
222 }
223 
224 TEST_F(MatchSelectPatternTest, FMinMismatchConstantZero2) {
225   parseAssembly(
226       "define float @test(float %a) {\n"
227       "  %1 = fcmp ogt float %a, -0.0\n"
228       "  %A = select i1 %1, float 0.0, float %a\n"
229       "  ret float %A\n"
230       "}\n");
231   // The sign of zero doesn't matter in fcmp.
232   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
233 }
234 
235 TEST_F(MatchSelectPatternTest, FMinMismatchConstantZero3) {
236   parseAssembly(
237       "define float @test(float %a) {\n"
238       "  %1 = fcmp olt float 0.0, %a\n"
239       "  %A = select i1 %1, float -0.0, float %a\n"
240       "  ret float %A\n"
241       "}\n");
242   // The sign of zero doesn't matter in fcmp.
243   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
244 }
245 
246 TEST_F(MatchSelectPatternTest, FMinMismatchConstantZero4) {
247   parseAssembly(
248       "define float @test(float %a) {\n"
249       "  %1 = fcmp ogt float %a, 0.0\n"
250       "  %A = select i1 %1, float -0.0, float %a\n"
251       "  ret float %A\n"
252       "}\n");
253   // The sign of zero doesn't matter in fcmp.
254   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
255 }
256 
257 TEST_F(MatchSelectPatternTest, FMinMismatchConstantZero5) {
258   parseAssembly(
259       "define float @test(float %a) {\n"
260       "  %1 = fcmp ogt float -0.0, %a\n"
261       "  %A = select i1 %1, float %a, float 0.0\n"
262       "  ret float %A\n"
263       "}\n");
264   // The sign of zero doesn't matter in fcmp.
265   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
266 }
267 
268 TEST_F(MatchSelectPatternTest, FMinMismatchConstantZero6) {
269   parseAssembly(
270       "define float @test(float %a) {\n"
271       "  %1 = fcmp olt float %a, -0.0\n"
272       "  %A = select i1 %1, float %a, float 0.0\n"
273       "  ret float %A\n"
274       "}\n");
275   // The sign of zero doesn't matter in fcmp.
276   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
277 }
278 
279 TEST_F(MatchSelectPatternTest, FMinMismatchConstantZero7) {
280   parseAssembly(
281       "define float @test(float %a) {\n"
282       "  %1 = fcmp ogt float 0.0, %a\n"
283       "  %A = select i1 %1, float %a, float -0.0\n"
284       "  ret float %A\n"
285       "}\n");
286   // The sign of zero doesn't matter in fcmp.
287   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
288 }
289 
290 TEST_F(MatchSelectPatternTest, FMinMismatchConstantZero8) {
291   parseAssembly(
292       "define float @test(float %a) {\n"
293       "  %1 = fcmp olt float %a, 0.0\n"
294       "  %A = select i1 %1, float %a, float -0.0\n"
295       "  ret float %A\n"
296       "}\n");
297   // The sign of zero doesn't matter in fcmp.
298   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
299 }
300 
301 TEST_F(MatchSelectPatternTest, FMaxMismatchConstantZero1) {
302   parseAssembly(
303       "define float @test(float %a) {\n"
304       "  %1 = fcmp ogt float -0.0, %a\n"
305       "  %A = select i1 %1, float 0.0, float %a\n"
306       "  ret float %A\n"
307       "}\n");
308   // The sign of zero doesn't matter in fcmp.
309   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
310 }
311 
312 TEST_F(MatchSelectPatternTest, FMaxMismatchConstantZero2) {
313   parseAssembly(
314       "define float @test(float %a) {\n"
315       "  %1 = fcmp olt float %a, -0.0\n"
316       "  %A = select i1 %1, float 0.0, float %a\n"
317       "  ret float %A\n"
318       "}\n");
319   // The sign of zero doesn't matter in fcmp.
320   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
321 }
322 
323 TEST_F(MatchSelectPatternTest, FMaxMismatchConstantZero3) {
324   parseAssembly(
325       "define float @test(float %a) {\n"
326       "  %1 = fcmp ogt float 0.0, %a\n"
327       "  %A = select i1 %1, float -0.0, float %a\n"
328       "  ret float %A\n"
329       "}\n");
330   // The sign of zero doesn't matter in fcmp.
331   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
332 }
333 
334 TEST_F(MatchSelectPatternTest, FMaxMismatchConstantZero4) {
335   parseAssembly(
336       "define float @test(float %a) {\n"
337       "  %1 = fcmp olt float %a, 0.0\n"
338       "  %A = select i1 %1, float -0.0, float %a\n"
339       "  ret float %A\n"
340       "}\n");
341   // The sign of zero doesn't matter in fcmp.
342   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
343 }
344 
345 TEST_F(MatchSelectPatternTest, FMaxMismatchConstantZero5) {
346   parseAssembly(
347       "define float @test(float %a) {\n"
348       "  %1 = fcmp olt float -0.0, %a\n"
349       "  %A = select i1 %1, float %a, float 0.0\n"
350       "  ret float %A\n"
351       "}\n");
352   // The sign of zero doesn't matter in fcmp.
353   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
354 }
355 
356 TEST_F(MatchSelectPatternTest, FMaxMismatchConstantZero6) {
357   parseAssembly(
358       "define float @test(float %a) {\n"
359       "  %1 = fcmp ogt float %a, -0.0\n"
360       "  %A = select i1 %1, float %a, float 0.0\n"
361       "  ret float %A\n"
362       "}\n");
363   // The sign of zero doesn't matter in fcmp.
364   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
365 }
366 
367 TEST_F(MatchSelectPatternTest, FMaxMismatchConstantZero7) {
368   parseAssembly(
369       "define float @test(float %a) {\n"
370       "  %1 = fcmp olt float 0.0, %a\n"
371       "  %A = select i1 %1, float %a, float -0.0\n"
372       "  ret float %A\n"
373       "}\n");
374   // The sign of zero doesn't matter in fcmp.
375   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
376 }
377 
378 TEST_F(MatchSelectPatternTest, FMaxMismatchConstantZero8) {
379   parseAssembly(
380       "define float @test(float %a) {\n"
381       "  %1 = fcmp ogt float %a, 0.0\n"
382       "  %A = select i1 %1, float %a, float -0.0\n"
383       "  ret float %A\n"
384       "}\n");
385   // The sign of zero doesn't matter in fcmp.
386   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
387 }
388 
389 TEST_F(MatchSelectPatternTest, FMinMismatchConstantZeroVecUndef) {
390   parseAssembly(
391       "define <2 x float> @test(<2 x float> %a) {\n"
392       "  %1 = fcmp ogt <2 x float> %a, <float -0.0, float -0.0>\n"
393       "  %A = select <2 x i1> %1, <2 x float> <float undef, float 0.0>, <2 x float> %a\n"
394       "  ret <2 x float> %A\n"
395       "}\n");
396   // An undef in a vector constant can not be back-propagated for this analysis.
397   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
398 }
399 
400 TEST_F(MatchSelectPatternTest, FMaxMismatchConstantZeroVecUndef) {
401   parseAssembly(
402       "define <2 x float> @test(<2 x float> %a) {\n"
403       "  %1 = fcmp ogt <2 x float> %a, zeroinitializer\n"
404       "  %A = select <2 x i1> %1, <2 x float> %a, <2 x float> <float -0.0, float undef>\n"
405       "  ret <2 x float> %A\n"
406       "}\n");
407   // An undef in a vector constant can not be back-propagated for this analysis.
408   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
409 }
410 
411 TEST_F(MatchSelectPatternTest, VectorFMinimum) {
412   parseAssembly(
413       "define <4 x float> @test(<4 x float> %a) {\n"
414       "  %1 = fcmp ule <4 x float> %a, \n"
415       "    <float 5.0, float 5.0, float 5.0, float 5.0>\n"
416       "  %A = select <4 x i1> %1, <4 x float> %a,\n"
417       "     <4 x float> <float 5.0, float 5.0, float 5.0, float 5.0>\n"
418       "  ret <4 x float> %A\n"
419       "}\n");
420   // Check that pattern matching works on vectors where each lane has the same
421   // unordered pattern.
422   expectPattern({SPF_FMINNUM, SPNB_RETURNS_NAN, false});
423 }
424 
425 TEST_F(MatchSelectPatternTest, VectorFMinOtherOrdered) {
426   parseAssembly(
427       "define <4 x float> @test(<4 x float> %a) {\n"
428       "  %1 = fcmp ole <4 x float> %a, \n"
429       "    <float 5.0, float 5.0, float 5.0, float 5.0>\n"
430       "  %A = select <4 x i1> %1, <4 x float> %a,\n"
431       "     <4 x float> <float 5.0, float 5.0, float 5.0, float 5.0>\n"
432       "  ret <4 x float> %A\n"
433       "}\n");
434   // Check that pattern matching works on vectors where each lane has the same
435   // ordered pattern.
436   expectPattern({SPF_FMINNUM, SPNB_RETURNS_OTHER, true});
437 }
438 
439 TEST_F(MatchSelectPatternTest, VectorNotFMinimum) {
440   parseAssembly(
441       "define <4 x float> @test(<4 x float> %a) {\n"
442       "  %1 = fcmp ule <4 x float> %a, \n"
443       "    <float 5.0, float 0x7ff8000000000000, float 5.0, float 5.0>\n"
444       "  %A = select <4 x i1> %1, <4 x float> %a,\n"
445       "     <4 x float> <float 5.0, float 0x7ff8000000000000, float 5.0, float "
446       "5.0>\n"
447       "  ret <4 x float> %A\n"
448       "}\n");
449   // The lane that contains a NaN (0x7ff80...) behaves like a
450   // non-NaN-propagating min and the other lines behave like a NaN-propagating
451   // min, so check that neither is returned.
452   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
453 }
454 
455 TEST_F(MatchSelectPatternTest, VectorNotFMinZero) {
456   parseAssembly(
457       "define <4 x float> @test(<4 x float> %a) {\n"
458       "  %1 = fcmp ule <4 x float> %a, \n"
459       "    <float 5.0, float -0.0, float 5.0, float 5.0>\n"
460       "  %A = select <4 x i1> %1, <4 x float> %a,\n"
461       "     <4 x float> <float 5.0, float 0.0, float 5.0, float 5.0>\n"
462       "  ret <4 x float> %A\n"
463       "}\n");
464   // Always selects the second lane of %a if it is positive or negative zero, so
465   // this is stricter than a min.
466   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
467 }
468 
469 TEST_F(MatchSelectPatternTest, DoubleCastU) {
470   parseAssembly(
471       "define i32 @test(i8 %a, i8 %b) {\n"
472       "  %1 = icmp ult i8 %a, %b\n"
473       "  %2 = zext i8 %a to i32\n"
474       "  %3 = zext i8 %b to i32\n"
475       "  %A = select i1 %1, i32 %2, i32 %3\n"
476       "  ret i32 %A\n"
477       "}\n");
478   // We should be able to look through the situation where we cast both operands
479   // to the select.
480   expectPattern({SPF_UMIN, SPNB_NA, false});
481 }
482 
483 TEST_F(MatchSelectPatternTest, DoubleCastS) {
484   parseAssembly(
485       "define i32 @test(i8 %a, i8 %b) {\n"
486       "  %1 = icmp slt i8 %a, %b\n"
487       "  %2 = sext i8 %a to i32\n"
488       "  %3 = sext i8 %b to i32\n"
489       "  %A = select i1 %1, i32 %2, i32 %3\n"
490       "  ret i32 %A\n"
491       "}\n");
492   // We should be able to look through the situation where we cast both operands
493   // to the select.
494   expectPattern({SPF_SMIN, SPNB_NA, false});
495 }
496 
497 TEST_F(MatchSelectPatternTest, DoubleCastBad) {
498   parseAssembly(
499       "define i32 @test(i8 %a, i8 %b) {\n"
500       "  %1 = icmp ult i8 %a, %b\n"
501       "  %2 = zext i8 %a to i32\n"
502       "  %3 = sext i8 %b to i32\n"
503       "  %A = select i1 %1, i32 %2, i32 %3\n"
504       "  ret i32 %A\n"
505       "}\n");
506   // The cast types here aren't the same, so we cannot match an UMIN.
507   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
508 }
509 
510 TEST_F(MatchSelectPatternTest, NotNotSMin) {
511   parseAssembly(
512       "define i8 @test(i8 %a, i8 %b) {\n"
513       "  %cmp = icmp sgt i8 %a, %b\n"
514       "  %an = xor i8 %a, -1\n"
515       "  %bn = xor i8 %b, -1\n"
516       "  %A = select i1 %cmp, i8 %an, i8 %bn\n"
517       "  ret i8 %A\n"
518       "}\n");
519   expectPattern({SPF_SMIN, SPNB_NA, false});
520 }
521 
522 TEST_F(MatchSelectPatternTest, NotNotSMinSwap) {
523   parseAssembly(
524       "define <2 x i8> @test(<2 x i8> %a, <2 x i8> %b) {\n"
525       "  %cmp = icmp slt <2 x i8> %a, %b\n"
526       "  %an = xor <2 x i8> %a, <i8 -1, i8-1>\n"
527       "  %bn = xor <2 x i8> %b, <i8 -1, i8-1>\n"
528       "  %A = select <2 x i1> %cmp, <2 x i8> %bn, <2 x i8> %an\n"
529       "  ret <2 x i8> %A\n"
530       "}\n");
531   expectPattern({SPF_SMIN, SPNB_NA, false});
532 }
533 
534 TEST_F(MatchSelectPatternTest, NotNotSMax) {
535   parseAssembly(
536       "define i8 @test(i8 %a, i8 %b) {\n"
537       "  %cmp = icmp slt i8 %a, %b\n"
538       "  %an = xor i8 %a, -1\n"
539       "  %bn = xor i8 %b, -1\n"
540       "  %A = select i1 %cmp, i8 %an, i8 %bn\n"
541       "  ret i8 %A\n"
542       "}\n");
543   expectPattern({SPF_SMAX, SPNB_NA, false});
544 }
545 
546 TEST_F(MatchSelectPatternTest, NotNotSMaxSwap) {
547   parseAssembly(
548       "define <2 x i8> @test(<2 x i8> %a, <2 x i8> %b) {\n"
549       "  %cmp = icmp sgt <2 x i8> %a, %b\n"
550       "  %an = xor <2 x i8> %a, <i8 -1, i8-1>\n"
551       "  %bn = xor <2 x i8> %b, <i8 -1, i8-1>\n"
552       "  %A = select <2 x i1> %cmp, <2 x i8> %bn, <2 x i8> %an\n"
553       "  ret <2 x i8> %A\n"
554       "}\n");
555   expectPattern({SPF_SMAX, SPNB_NA, false});
556 }
557 
558 TEST_F(MatchSelectPatternTest, NotNotUMin) {
559   parseAssembly(
560       "define <2 x i8> @test(<2 x i8> %a, <2 x i8> %b) {\n"
561       "  %cmp = icmp ugt <2 x i8> %a, %b\n"
562       "  %an = xor <2 x i8> %a, <i8 -1, i8-1>\n"
563       "  %bn = xor <2 x i8> %b, <i8 -1, i8-1>\n"
564       "  %A = select <2 x i1> %cmp, <2 x i8> %an, <2 x i8> %bn\n"
565       "  ret <2 x i8> %A\n"
566       "}\n");
567   expectPattern({SPF_UMIN, SPNB_NA, false});
568 }
569 
570 TEST_F(MatchSelectPatternTest, NotNotUMinSwap) {
571   parseAssembly(
572       "define i8 @test(i8 %a, i8 %b) {\n"
573       "  %cmp = icmp ult i8 %a, %b\n"
574       "  %an = xor i8 %a, -1\n"
575       "  %bn = xor i8 %b, -1\n"
576       "  %A = select i1 %cmp, i8 %bn, i8 %an\n"
577       "  ret i8 %A\n"
578       "}\n");
579   expectPattern({SPF_UMIN, SPNB_NA, false});
580 }
581 
582 TEST_F(MatchSelectPatternTest, NotNotUMax) {
583   parseAssembly(
584       "define <2 x i8> @test(<2 x i8> %a, <2 x i8> %b) {\n"
585       "  %cmp = icmp ult <2 x i8> %a, %b\n"
586       "  %an = xor <2 x i8> %a, <i8 -1, i8-1>\n"
587       "  %bn = xor <2 x i8> %b, <i8 -1, i8-1>\n"
588       "  %A = select <2 x i1> %cmp, <2 x i8> %an, <2 x i8> %bn\n"
589       "  ret <2 x i8> %A\n"
590       "}\n");
591   expectPattern({SPF_UMAX, SPNB_NA, false});
592 }
593 
594 TEST_F(MatchSelectPatternTest, NotNotUMaxSwap) {
595   parseAssembly(
596       "define i8 @test(i8 %a, i8 %b) {\n"
597       "  %cmp = icmp ugt i8 %a, %b\n"
598       "  %an = xor i8 %a, -1\n"
599       "  %bn = xor i8 %b, -1\n"
600       "  %A = select i1 %cmp, i8 %bn, i8 %an\n"
601       "  ret i8 %A\n"
602       "}\n");
603   expectPattern({SPF_UMAX, SPNB_NA, false});
604 }
605 
606 TEST_F(MatchSelectPatternTest, NotNotEq) {
607   parseAssembly(
608       "define i8 @test(i8 %a, i8 %b) {\n"
609       "  %cmp = icmp eq i8 %a, %b\n"
610       "  %an = xor i8 %a, -1\n"
611       "  %bn = xor i8 %b, -1\n"
612       "  %A = select i1 %cmp, i8 %bn, i8 %an\n"
613       "  ret i8 %A\n"
614       "}\n");
615   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
616 }
617 
618 TEST_F(MatchSelectPatternTest, NotNotNe) {
619   parseAssembly(
620       "define i8 @test(i8 %a, i8 %b) {\n"
621       "  %cmp = icmp ne i8 %a, %b\n"
622       "  %an = xor i8 %a, -1\n"
623       "  %bn = xor i8 %b, -1\n"
624       "  %A = select i1 %cmp, i8 %bn, i8 %an\n"
625       "  ret i8 %A\n"
626       "}\n");
627   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
628 }
629 
630 TEST(ValueTracking, GuaranteedToTransferExecutionToSuccessor) {
631   StringRef Assembly =
632       "declare void @nounwind_readonly(ptr) nounwind readonly "
633       "declare void @nounwind_argmemonly(ptr) nounwind argmemonly "
634       "declare void @nounwind_willreturn(ptr) nounwind willreturn "
635       "declare void @throws_but_readonly(ptr) readonly "
636       "declare void @throws_but_argmemonly(ptr) argmemonly "
637       "declare void @throws_but_willreturn(ptr) willreturn "
638       " "
639       "declare void @unknown(ptr) "
640       " "
641       "define void @f(ptr %p) { "
642       "  call void @nounwind_readonly(ptr %p) "
643       "  call void @nounwind_argmemonly(ptr %p) "
644       "  call void @nounwind_willreturn(ptr %p)"
645       "  call void @throws_but_readonly(ptr %p) "
646       "  call void @throws_but_argmemonly(ptr %p) "
647       "  call void @throws_but_willreturn(ptr %p) "
648       "  call void @unknown(ptr %p) nounwind readonly "
649       "  call void @unknown(ptr %p) nounwind argmemonly "
650       "  call void @unknown(ptr %p) nounwind willreturn "
651       "  call void @unknown(ptr %p) readonly "
652       "  call void @unknown(ptr %p) argmemonly "
653       "  call void @unknown(ptr %p) willreturn "
654       "  ret void "
655       "} ";
656 
657   LLVMContext Context;
658   SMDiagnostic Error;
659   auto M = parseAssemblyString(Assembly, Error, Context);
660   assert(M && "Bad assembly?");
661 
662   auto *F = M->getFunction("f");
663   assert(F && "Bad assembly?");
664 
665   auto &BB = F->getEntryBlock();
666   bool ExpectedAnswers[] = {
667       false, // call void @nounwind_readonly(ptr %p)
668       false, // call void @nounwind_argmemonly(ptr %p)
669       true,  // call void @nounwind_willreturn(ptr %p)
670       false, // call void @throws_but_readonly(ptr %p)
671       false, // call void @throws_but_argmemonly(ptr %p)
672       false, // call void @throws_but_willreturn(ptr %p)
673       false, // call void @unknown(ptr %p) nounwind readonly
674       false, // call void @unknown(ptr %p) nounwind argmemonly
675       true,  // call void @unknown(ptr %p) nounwind willreturn
676       false, // call void @unknown(ptr %p) readonly
677       false, // call void @unknown(ptr %p) argmemonly
678       false, // call void @unknown(ptr %p) willreturn
679       false, // ret void
680   };
681 
682   int Index = 0;
683   for (auto &I : BB) {
684     EXPECT_EQ(isGuaranteedToTransferExecutionToSuccessor(&I),
685               ExpectedAnswers[Index])
686         << "Incorrect answer at instruction " << Index << " = " << I;
687     Index++;
688   }
689 }
690 
691 TEST_F(ValueTrackingTest, ComputeNumSignBits_PR32045) {
692   parseAssembly(
693       "define i32 @test(i32 %a) {\n"
694       "  %A = ashr i32 %a, -1\n"
695       "  ret i32 %A\n"
696       "}\n");
697   EXPECT_EQ(ComputeNumSignBits(A, M->getDataLayout()), 32u);
698 }
699 
700 // No guarantees for canonical IR in this analysis, so this just bails out.
701 TEST_F(ValueTrackingTest, ComputeNumSignBits_Shuffle) {
702   parseAssembly(
703       "define <2 x i32> @test() {\n"
704       "  %A = shufflevector <2 x i32> undef, <2 x i32> undef, <2 x i32> <i32 0, i32 0>\n"
705       "  ret <2 x i32> %A\n"
706       "}\n");
707   EXPECT_EQ(ComputeNumSignBits(A, M->getDataLayout()), 1u);
708 }
709 
710 // No guarantees for canonical IR in this analysis, so a shuffle element that
711 // references an undef value means this can't return any extra information.
712 TEST_F(ValueTrackingTest, ComputeNumSignBits_Shuffle2) {
713   parseAssembly(
714       "define <2 x i32> @test(<2 x i1> %x) {\n"
715       "  %sext = sext <2 x i1> %x to <2 x i32>\n"
716       "  %A = shufflevector <2 x i32> %sext, <2 x i32> undef, <2 x i32> <i32 0, i32 2>\n"
717       "  ret <2 x i32> %A\n"
718       "}\n");
719   EXPECT_EQ(ComputeNumSignBits(A, M->getDataLayout()), 1u);
720 }
721 
722 TEST_F(ValueTrackingTest, impliesPoisonTest_Identity) {
723   parseAssembly("define void @test(i32 %x, i32 %y) {\n"
724                 "  %A = add i32 %x, %y\n"
725                 "  ret void\n"
726                 "}");
727   EXPECT_TRUE(impliesPoison(A, A));
728 }
729 
730 TEST_F(ValueTrackingTest, impliesPoisonTest_ICmp) {
731   parseAssembly("define void @test(i32 %x) {\n"
732                 "  %A2 = icmp eq i32 %x, 0\n"
733                 "  %A = icmp eq i32 %x, 1\n"
734                 "  ret void\n"
735                 "}");
736   EXPECT_TRUE(impliesPoison(A2, A));
737 }
738 
739 TEST_F(ValueTrackingTest, impliesPoisonTest_ICmpUnknown) {
740   parseAssembly("define void @test(i32 %x, i32 %y) {\n"
741                 "  %A2 = icmp eq i32 %x, %y\n"
742                 "  %A = icmp eq i32 %x, 1\n"
743                 "  ret void\n"
744                 "}");
745   EXPECT_FALSE(impliesPoison(A2, A));
746 }
747 
748 TEST_F(ValueTrackingTest, impliesPoisonTest_AddNswOkay) {
749   parseAssembly("define void @test(i32 %x) {\n"
750                 "  %A2 = add nsw i32 %x, 1\n"
751                 "  %A = add i32 %A2, 1\n"
752                 "  ret void\n"
753                 "}");
754   EXPECT_TRUE(impliesPoison(A2, A));
755 }
756 
757 TEST_F(ValueTrackingTest, impliesPoisonTest_AddNswOkay2) {
758   parseAssembly("define void @test(i32 %x) {\n"
759                 "  %A2 = add i32 %x, 1\n"
760                 "  %A = add nsw i32 %A2, 1\n"
761                 "  ret void\n"
762                 "}");
763   EXPECT_TRUE(impliesPoison(A2, A));
764 }
765 
766 TEST_F(ValueTrackingTest, impliesPoisonTest_AddNsw) {
767   parseAssembly("define void @test(i32 %x) {\n"
768                 "  %A2 = add nsw i32 %x, 1\n"
769                 "  %A = add i32 %x, 1\n"
770                 "  ret void\n"
771                 "}");
772   EXPECT_FALSE(impliesPoison(A2, A));
773 }
774 
775 TEST_F(ValueTrackingTest, impliesPoisonTest_Cmp) {
776   parseAssembly("define void @test(i32 %x, i32 %y, i1 %c) {\n"
777                 "  %A2 = icmp eq i32 %x, %y\n"
778                 "  %A0 = icmp ult i32 %x, %y\n"
779                 "  %A = or i1 %A0, %c\n"
780                 "  ret void\n"
781                 "}");
782   EXPECT_TRUE(impliesPoison(A2, A));
783 }
784 
785 TEST_F(ValueTrackingTest, impliesPoisonTest_FCmpFMF) {
786   parseAssembly("define void @test(float %x, float %y, i1 %c) {\n"
787                 "  %A2 = fcmp nnan oeq float %x, %y\n"
788                 "  %A0 = fcmp olt float %x, %y\n"
789                 "  %A = or i1 %A0, %c\n"
790                 "  ret void\n"
791                 "}");
792   EXPECT_FALSE(impliesPoison(A2, A));
793 }
794 
795 TEST_F(ValueTrackingTest, impliesPoisonTest_AddSubSameOps) {
796   parseAssembly("define void @test(i32 %x, i32 %y, i1 %c) {\n"
797                 "  %A2 = add i32 %x, %y\n"
798                 "  %A = sub i32 %x, %y\n"
799                 "  ret void\n"
800                 "}");
801   EXPECT_TRUE(impliesPoison(A2, A));
802 }
803 
804 TEST_F(ValueTrackingTest, impliesPoisonTest_MaskCmp) {
805   parseAssembly("define void @test(i32 %x, i32 %y, i1 %c) {\n"
806                 "  %M2 = and i32 %x, 7\n"
807                 "  %A2 = icmp eq i32 %M2, 1\n"
808                 "  %M = and i32 %x, 15\n"
809                 "  %A = icmp eq i32 %M, 3\n"
810                 "  ret void\n"
811                 "}");
812   EXPECT_TRUE(impliesPoison(A2, A));
813 }
814 
815 TEST_F(ValueTrackingTest, ComputeNumSignBits_Shuffle_Pointers) {
816   parseAssembly(
817       "define <2 x ptr> @test(<2 x ptr> %x) {\n"
818       "  %A = shufflevector <2 x ptr> zeroinitializer, <2 x ptr> undef, <2 x i32> zeroinitializer\n"
819       "  ret <2 x ptr> %A\n"
820       "}\n");
821   EXPECT_EQ(ComputeNumSignBits(A, M->getDataLayout()), 64u);
822 }
823 
824 TEST(ValueTracking, propagatesPoison) {
825   std::string AsmHead =
826       "declare i32 @g(i32)\n"
827       "declare {i32, i1} @llvm.sadd.with.overflow.i32(i32 %a, i32 %b)\n"
828       "declare {i32, i1} @llvm.ssub.with.overflow.i32(i32 %a, i32 %b)\n"
829       "declare {i32, i1} @llvm.smul.with.overflow.i32(i32 %a, i32 %b)\n"
830       "declare {i32, i1} @llvm.uadd.with.overflow.i32(i32 %a, i32 %b)\n"
831       "declare {i32, i1} @llvm.usub.with.overflow.i32(i32 %a, i32 %b)\n"
832       "declare {i32, i1} @llvm.umul.with.overflow.i32(i32 %a, i32 %b)\n"
833       "declare float @llvm.sqrt.f32(float)\n"
834       "declare float @llvm.powi.f32.i32(float, i32)\n"
835       "declare float @llvm.sin.f32(float)\n"
836       "declare float @llvm.cos.f32(float)\n"
837       "declare float @llvm.pow.f32(float, float)\n"
838       "declare float @llvm.exp.f32(float)\n"
839       "declare float @llvm.exp2.f32(float)\n"
840       "declare float @llvm.log.f32(float)\n"
841       "declare float @llvm.log10.f32(float)\n"
842       "declare float @llvm.log2.f32(float)\n"
843       "declare float @llvm.fma.f32(float, float, float)\n"
844       "declare float @llvm.fabs.f32(float)\n"
845       "declare float @llvm.minnum.f32(float, float)\n"
846       "declare float @llvm.maxnum.f32(float, float)\n"
847       "declare float @llvm.minimum.f32(float, float)\n"
848       "declare float @llvm.maximum.f32(float, float)\n"
849       "declare float @llvm.copysign.f32(float, float)\n"
850       "declare float @llvm.floor.f32(float)\n"
851       "declare float @llvm.ceil.f32(float)\n"
852       "declare float @llvm.trunc.f32(float)\n"
853       "declare float @llvm.rint.f32(float)\n"
854       "declare float @llvm.nearbyint.f32(float)\n"
855       "declare float @llvm.round.f32(float)\n"
856       "declare float @llvm.roundeven.f32(float)\n"
857       "declare i32 @llvm.lround.f32(float)\n"
858       "declare i64 @llvm.llround.f32(float)\n"
859       "declare i32 @llvm.lrint.f32(float)\n"
860       "declare i64 @llvm.llrint.f32(float)\n"
861       "declare float @llvm.fmuladd.f32(float, float, float)\n"
862       "define void @f(i32 %x, i32 %y, float %fx, float %fy, "
863       "i1 %cond, ptr %p) {\n";
864   std::string AsmTail = "  ret void\n}";
865   // (propagates poison?, IR instruction)
866   SmallVector<std::tuple<bool, std::string, unsigned>, 32> Data = {
867       {true, "add i32 %x, %y", 0},
868       {true, "add i32 %x, %y", 1},
869       {true, "add nsw nuw i32 %x, %y", 0},
870       {true, "add nsw nuw i32 %x, %y", 1},
871       {true, "ashr i32 %x, %y", 0},
872       {true, "ashr i32 %x, %y", 1},
873       {true, "lshr exact i32 %x, 31", 0},
874       {true, "lshr exact i32 %x, 31", 1},
875       {true, "fadd float %fx, %fy", 0},
876       {true, "fadd float %fx, %fy", 1},
877       {true, "fsub float %fx, %fy", 0},
878       {true, "fsub float %fx, %fy", 1},
879       {true, "fmul float %fx, %fy", 0},
880       {true, "fmul float %fx, %fy", 1},
881       {true, "fdiv float %fx, %fy", 0},
882       {true, "fdiv float %fx, %fy", 1},
883       {true, "frem float %fx, %fy", 0},
884       {true, "frem float %fx, %fy", 1},
885       {true, "fneg float %fx", 0},
886       {true, "fcmp oeq float %fx, %fy", 0},
887       {true, "fcmp oeq float %fx, %fy", 1},
888       {true, "icmp eq i32 %x, %y", 0},
889       {true, "icmp eq i32 %x, %y", 1},
890       {true, "getelementptr i8, ptr %p, i32 %x", 0},
891       {true, "getelementptr i8, ptr %p, i32 %x", 1},
892       {true, "getelementptr inbounds i8, ptr %p, i32 %x", 0},
893       {true, "getelementptr inbounds i8, ptr %p, i32 %x", 1},
894       {true, "bitcast float %fx to i32", 0},
895       {true, "select i1 %cond, i32 %x, i32 %y", 0},
896       {false, "select i1 %cond, i32 %x, i32 %y", 1},
897       {false, "select i1 %cond, i32 %x, i32 %y", 2},
898       {false, "freeze i32 %x", 0},
899       {true, "udiv i32 %x, %y", 0},
900       {true, "udiv i32 %x, %y", 1},
901       {true, "urem i32 %x, %y", 0},
902       {true, "urem i32 %x, %y", 1},
903       {true, "sdiv exact i32 %x, %y", 0},
904       {true, "sdiv exact i32 %x, %y", 1},
905       {true, "srem i32 %x, %y", 0},
906       {true, "srem i32 %x, %y", 1},
907       {false, "call i32 @g(i32 %x)", 0},
908       {false, "call i32 @g(i32 %x)", 1},
909       {true, "call {i32, i1} @llvm.sadd.with.overflow.i32(i32 %x, i32 %y)", 0},
910       {true, "call {i32, i1} @llvm.ssub.with.overflow.i32(i32 %x, i32 %y)", 0},
911       {true, "call {i32, i1} @llvm.smul.with.overflow.i32(i32 %x, i32 %y)", 0},
912       {true, "call {i32, i1} @llvm.uadd.with.overflow.i32(i32 %x, i32 %y)", 0},
913       {true, "call {i32, i1} @llvm.usub.with.overflow.i32(i32 %x, i32 %y)", 0},
914       {true, "call {i32, i1} @llvm.umul.with.overflow.i32(i32 %x, i32 %y)", 0},
915       {false, "call float @llvm.sqrt.f32(float %fx)", 0},
916       {false, "call float @llvm.powi.f32.i32(float %fx, i32 %x)", 0},
917       {false, "call float @llvm.sin.f32(float %fx)", 0},
918       {false, "call float @llvm.cos.f32(float %fx)", 0},
919       {false, "call float @llvm.pow.f32(float %fx, float %fy)", 0},
920       {false, "call float @llvm.exp.f32(float %fx)", 0},
921       {false, "call float @llvm.exp2.f32(float %fx)", 0},
922       {false, "call float @llvm.log.f32(float %fx)", 0},
923       {false, "call float @llvm.log10.f32(float %fx)", 0},
924       {false, "call float @llvm.log2.f32(float %fx)", 0},
925       {false, "call float @llvm.fma.f32(float %fx, float %fx, float %fy)", 0},
926       {false, "call float @llvm.fabs.f32(float %fx)", 0},
927       {false, "call float @llvm.minnum.f32(float %fx, float %fy)", 0},
928       {false, "call float @llvm.maxnum.f32(float %fx, float %fy)", 0},
929       {false, "call float @llvm.minimum.f32(float %fx, float %fy)", 0},
930       {false, "call float @llvm.maximum.f32(float %fx, float %fy)", 0},
931       {false, "call float @llvm.copysign.f32(float %fx, float %fy)", 0},
932       {false, "call float @llvm.floor.f32(float %fx)", 0},
933       {false, "call float @llvm.ceil.f32(float %fx)", 0},
934       {false, "call float @llvm.trunc.f32(float %fx)", 0},
935       {false, "call float @llvm.rint.f32(float %fx)", 0},
936       {false, "call float @llvm.nearbyint.f32(float %fx)", 0},
937       {false, "call float @llvm.round.f32(float %fx)", 0},
938       {false, "call float @llvm.roundeven.f32(float %fx)", 0},
939       {false, "call i32 @llvm.lround.f32(float %fx)", 0},
940       {false, "call i64 @llvm.llround.f32(float %fx)", 0},
941       {false, "call i32 @llvm.lrint.f32(float %fx)", 0},
942       {false, "call i64 @llvm.llrint.f32(float %fx)", 0},
943       {false, "call float @llvm.fmuladd.f32(float %fx, float %fx, float %fy)",
944        0}};
945 
946   std::string AssemblyStr = AsmHead;
947   for (auto &Itm : Data)
948     AssemblyStr += std::get<1>(Itm) + "\n";
949   AssemblyStr += AsmTail;
950 
951   LLVMContext Context;
952   SMDiagnostic Error;
953   auto M = parseAssemblyString(AssemblyStr, Error, Context);
954   assert(M && "Bad assembly?");
955 
956   auto *F = M->getFunction("f");
957   assert(F && "Bad assembly?");
958 
959   auto &BB = F->getEntryBlock();
960 
961   int Index = 0;
962   for (auto &I : BB) {
963     if (isa<ReturnInst>(&I))
964       break;
965     bool ExpectedVal = std::get<0>(Data[Index]);
966     unsigned OpIdx = std::get<2>(Data[Index]);
967     EXPECT_EQ(propagatesPoison(I.getOperandUse(OpIdx)), ExpectedVal)
968         << "Incorrect answer at instruction " << Index << " = " << I;
969     Index++;
970   }
971 }
972 
973 TEST_F(ValueTrackingTest, programUndefinedIfPoison) {
974   parseAssembly("declare i32 @any_num()"
975                 "define void @test(i32 %mask) {\n"
976                 "  %A = call i32 @any_num()\n"
977                 "  %B = or i32 %A, %mask\n"
978                 "  udiv i32 1, %B"
979                 "  ret void\n"
980                 "}\n");
981   // If %A was poison, udiv raises UB regardless of %mask's value
982   EXPECT_EQ(programUndefinedIfPoison(A), true);
983 }
984 
985 TEST_F(ValueTrackingTest, programUndefinedIfPoisonSelect) {
986   parseAssembly("declare i32 @any_num()"
987                 "define void @test(i1 %Cond) {\n"
988                 "  %A = call i32 @any_num()\n"
989                 "  %B = add i32 %A, 1\n"
990                 "  %C = select i1 %Cond, i32 %A, i32 %B\n"
991                 "  udiv i32 1, %C"
992                 "  ret void\n"
993                 "}\n");
994   // If A is poison, B is also poison, and therefore C is poison regardless of
995   // the value of %Cond.
996   EXPECT_EQ(programUndefinedIfPoison(A), true);
997 }
998 
999 TEST_F(ValueTrackingTest, programUndefinedIfUndefOrPoison) {
1000   parseAssembly("declare i32 @any_num()"
1001                 "define void @test(i32 %mask) {\n"
1002                 "  %A = call i32 @any_num()\n"
1003                 "  %B = or i32 %A, %mask\n"
1004                 "  udiv i32 1, %B"
1005                 "  ret void\n"
1006                 "}\n");
1007   // If %A was undef and %mask was 1, udiv does not raise UB
1008   EXPECT_EQ(programUndefinedIfUndefOrPoison(A), false);
1009 }
1010 
1011 TEST_F(ValueTrackingTest, isGuaranteedNotToBePoison_exploitBranchCond) {
1012   parseAssembly("declare i1 @any_bool()"
1013                 "define void @test(i1 %y) {\n"
1014                 "  %A = call i1 @any_bool()\n"
1015                 "  %cond = and i1 %A, %y\n"
1016                 "  br i1 %cond, label %BB1, label %BB2\n"
1017                 "BB1:\n"
1018                 "  ret void\n"
1019                 "BB2:\n"
1020                 "  ret void\n"
1021                 "}\n");
1022   DominatorTree DT(*F);
1023   for (auto &BB : *F) {
1024     if (&BB == &F->getEntryBlock())
1025       continue;
1026 
1027     EXPECT_EQ(isGuaranteedNotToBePoison(A, nullptr, BB.getTerminator(), &DT),
1028               true)
1029         << "isGuaranteedNotToBePoison does not hold at " << *BB.getTerminator();
1030   }
1031 }
1032 
1033 TEST_F(ValueTrackingTest, isGuaranteedNotToBePoison_phi) {
1034   parseAssembly("declare i32 @any_i32(i32)"
1035                 "define void @test() {\n"
1036                 "ENTRY:\n"
1037                 "  br label %LOOP\n"
1038                 "LOOP:\n"
1039                 "  %A = phi i32 [0, %ENTRY], [%A.next, %NEXT]\n"
1040                 "  %A.next = call i32 @any_i32(i32 %A)\n"
1041                 "  %cond = icmp eq i32 %A.next, 0\n"
1042                 "  br i1 %cond, label %NEXT, label %EXIT\n"
1043                 "NEXT:\n"
1044                 "  br label %LOOP\n"
1045                 "EXIT:\n"
1046                 "  ret void\n"
1047                 "}\n");
1048   DominatorTree DT(*F);
1049   for (auto &BB : *F) {
1050     if (BB.getName() == "LOOP") {
1051       EXPECT_EQ(isGuaranteedNotToBePoison(A, nullptr, A, &DT), true)
1052           << "isGuaranteedNotToBePoison does not hold";
1053     }
1054   }
1055 }
1056 
1057 TEST_F(ValueTrackingTest, isGuaranteedNotToBeUndefOrPoison) {
1058   parseAssembly("declare void @f(i32 noundef)"
1059                 "define void @test(i32 %x) {\n"
1060                 "  %A = bitcast i32 %x to i32\n"
1061                 "  call void @f(i32 noundef %x)\n"
1062                 "  ret void\n"
1063                 "}\n");
1064   EXPECT_EQ(isGuaranteedNotToBeUndefOrPoison(A), true);
1065   EXPECT_EQ(isGuaranteedNotToBeUndefOrPoison(UndefValue::get(IntegerType::get(Context, 8))), false);
1066   EXPECT_EQ(isGuaranteedNotToBeUndefOrPoison(PoisonValue::get(IntegerType::get(Context, 8))), false);
1067   EXPECT_EQ(isGuaranteedNotToBePoison(UndefValue::get(IntegerType::get(Context, 8))), true);
1068   EXPECT_EQ(isGuaranteedNotToBePoison(PoisonValue::get(IntegerType::get(Context, 8))), false);
1069 
1070   Type *Int32Ty = Type::getInt32Ty(Context);
1071   Constant *CU = UndefValue::get(Int32Ty);
1072   Constant *CP = PoisonValue::get(Int32Ty);
1073   Constant *C1 = ConstantInt::get(Int32Ty, 1);
1074   Constant *C2 = ConstantInt::get(Int32Ty, 2);
1075 
1076   {
1077     Constant *V1 = ConstantVector::get({C1, C2});
1078     EXPECT_TRUE(isGuaranteedNotToBeUndefOrPoison(V1));
1079     EXPECT_TRUE(isGuaranteedNotToBePoison(V1));
1080   }
1081 
1082   {
1083     Constant *V2 = ConstantVector::get({C1, CU});
1084     EXPECT_FALSE(isGuaranteedNotToBeUndefOrPoison(V2));
1085     EXPECT_TRUE(isGuaranteedNotToBePoison(V2));
1086   }
1087 
1088   {
1089     Constant *V3 = ConstantVector::get({C1, CP});
1090     EXPECT_FALSE(isGuaranteedNotToBeUndefOrPoison(V3));
1091     EXPECT_FALSE(isGuaranteedNotToBePoison(V3));
1092   }
1093 }
1094 
1095 TEST_F(ValueTrackingTest, isGuaranteedNotToBeUndefOrPoison_assume) {
1096   parseAssembly("declare i1 @f_i1()\n"
1097                 "declare i32 @f_i32()\n"
1098                 "declare void @llvm.assume(i1)\n"
1099                 "define void @test() {\n"
1100                 "  %A = call i32 @f_i32()\n"
1101                 "  %cond = call i1 @f_i1()\n"
1102                 "  %CxtI = add i32 0, 0\n"
1103                 "  br i1 %cond, label %BB1, label %EXIT\n"
1104                 "BB1:\n"
1105                 "  %CxtI2 = add i32 0, 0\n"
1106                 "  %cond2 = call i1 @f_i1()\n"
1107                 "  call void @llvm.assume(i1 true) [ \"noundef\"(i32 %A) ]\n"
1108                 "  br i1 %cond2, label %BB2, label %EXIT\n"
1109                 "BB2:\n"
1110                 "  %CxtI3 = add i32 0, 0\n"
1111                 "  ret void\n"
1112                 "EXIT:\n"
1113                 "  ret void\n"
1114                 "}");
1115   AssumptionCache AC(*F);
1116   DominatorTree DT(*F);
1117   EXPECT_FALSE(isGuaranteedNotToBeUndefOrPoison(A, &AC, CxtI, &DT));
1118   EXPECT_FALSE(isGuaranteedNotToBeUndefOrPoison(A, &AC, CxtI2, &DT));
1119   EXPECT_TRUE(isGuaranteedNotToBeUndefOrPoison(A, &AC, CxtI3, &DT));
1120 }
1121 
1122 TEST(ValueTracking, canCreatePoisonOrUndef) {
1123   std::string AsmHead =
1124       "@s = external dso_local global i32, align 1\n"
1125       "declare i32 @g(i32)\n"
1126       "declare {i32, i1} @llvm.sadd.with.overflow.i32(i32 %a, i32 %b)\n"
1127       "declare {i32, i1} @llvm.ssub.with.overflow.i32(i32 %a, i32 %b)\n"
1128       "declare {i32, i1} @llvm.smul.with.overflow.i32(i32 %a, i32 %b)\n"
1129       "declare {i32, i1} @llvm.uadd.with.overflow.i32(i32 %a, i32 %b)\n"
1130       "declare {i32, i1} @llvm.usub.with.overflow.i32(i32 %a, i32 %b)\n"
1131       "declare {i32, i1} @llvm.umul.with.overflow.i32(i32 %a, i32 %b)\n"
1132       "define void @f(i32 %x, i32 %y, float %fx, float %fy, i1 %cond, "
1133       "<4 x i32> %vx, <4 x i32> %vx2, <vscale x 4 x i32> %svx, ptr %p) {\n";
1134   std::string AsmTail = "  ret void\n}";
1135   // (can create poison?, can create undef?, IR instruction)
1136   SmallVector<std::pair<std::pair<bool, bool>, std::string>, 32> Data = {
1137       {{false, false}, "add i32 %x, %y"},
1138       {{true, false}, "add nsw nuw i32 %x, %y"},
1139       {{true, false}, "shl i32 %x, %y"},
1140       {{true, false}, "shl <4 x i32> %vx, %vx2"},
1141       {{true, false}, "shl nsw i32 %x, %y"},
1142       {{true, false}, "shl nsw <4 x i32> %vx, <i32 0, i32 1, i32 2, i32 3>"},
1143       {{false, false}, "shl i32 %x, 31"},
1144       {{true, false}, "shl i32 %x, 32"},
1145       {{false, false}, "shl <4 x i32> %vx, <i32 0, i32 1, i32 2, i32 3>"},
1146       {{true, false}, "shl <4 x i32> %vx, <i32 0, i32 1, i32 2, i32 32>"},
1147       {{true, false}, "ashr i32 %x, %y"},
1148       {{true, false}, "ashr exact i32 %x, %y"},
1149       {{false, false}, "ashr i32 %x, 31"},
1150       {{true, false}, "ashr exact i32 %x, 31"},
1151       {{false, false}, "ashr <4 x i32> %vx, <i32 0, i32 1, i32 2, i32 3>"},
1152       {{true, false}, "ashr <4 x i32> %vx, <i32 0, i32 1, i32 2, i32 32>"},
1153       {{true, false}, "ashr exact <4 x i32> %vx, <i32 0, i32 1, i32 2, i32 3>"},
1154       {{true, false}, "lshr i32 %x, %y"},
1155       {{true, false}, "lshr exact i32 %x, 31"},
1156       {{false, false}, "udiv i32 %x, %y"},
1157       {{true, false}, "udiv exact i32 %x, %y"},
1158       {{false, false}, "getelementptr i8, ptr %p, i32 %x"},
1159       {{true, false}, "getelementptr inbounds i8, ptr %p, i32 %x"},
1160       {{true, false}, "fneg nnan float %fx"},
1161       {{false, false}, "fneg float %fx"},
1162       {{false, false}, "fadd float %fx, %fy"},
1163       {{true, false}, "fadd nnan float %fx, %fy"},
1164       {{false, false}, "urem i32 %x, %y"},
1165       {{true, false}, "fptoui float %fx to i32"},
1166       {{true, false}, "fptosi float %fx to i32"},
1167       {{false, false}, "bitcast float %fx to i32"},
1168       {{false, false}, "select i1 %cond, i32 %x, i32 %y"},
1169       {{true, false}, "select nnan i1 %cond, float %fx, float %fy"},
1170       {{true, false}, "extractelement <4 x i32> %vx, i32 %x"},
1171       {{false, false}, "extractelement <4 x i32> %vx, i32 3"},
1172       {{true, false}, "extractelement <vscale x 4 x i32> %svx, i32 4"},
1173       {{true, false}, "insertelement <4 x i32> %vx, i32 %x, i32 %y"},
1174       {{false, false}, "insertelement <4 x i32> %vx, i32 %x, i32 3"},
1175       {{true, false}, "insertelement <vscale x 4 x i32> %svx, i32 %x, i32 4"},
1176       {{false, false}, "freeze i32 %x"},
1177       {{false, false},
1178        "shufflevector <4 x i32> %vx, <4 x i32> %vx2, "
1179        "<4 x i32> <i32 0, i32 1, i32 2, i32 3>"},
1180       {{false, true},
1181        "shufflevector <4 x i32> %vx, <4 x i32> %vx2, "
1182        "<4 x i32> <i32 0, i32 1, i32 2, i32 undef>"},
1183       {{false, true},
1184        "shufflevector <vscale x 4 x i32> %svx, "
1185        "<vscale x 4 x i32> %svx, <vscale x 4 x i32> undef"},
1186       {{true, false}, "call i32 @g(i32 %x)"},
1187       {{false, false}, "call noundef i32 @g(i32 %x)"},
1188       {{true, false}, "fcmp nnan oeq float %fx, %fy"},
1189       {{false, false}, "fcmp oeq float %fx, %fy"},
1190       {{true, false}, "ashr i32 %x, ptrtoint (ptr @s to i32)"},
1191       {{false, false},
1192        "call {i32, i1} @llvm.sadd.with.overflow.i32(i32 %x, i32 %y)"},
1193       {{false, false},
1194        "call {i32, i1} @llvm.ssub.with.overflow.i32(i32 %x, i32 %y)"},
1195       {{false, false},
1196        "call {i32, i1} @llvm.smul.with.overflow.i32(i32 %x, i32 %y)"},
1197       {{false, false},
1198        "call {i32, i1} @llvm.uadd.with.overflow.i32(i32 %x, i32 %y)"},
1199       {{false, false},
1200        "call {i32, i1} @llvm.usub.with.overflow.i32(i32 %x, i32 %y)"},
1201       {{false, false},
1202        "call {i32, i1} @llvm.umul.with.overflow.i32(i32 %x, i32 %y)"}};
1203 
1204   std::string AssemblyStr = AsmHead;
1205   for (auto &Itm : Data)
1206     AssemblyStr += Itm.second + "\n";
1207   AssemblyStr += AsmTail;
1208 
1209   LLVMContext Context;
1210   SMDiagnostic Error;
1211   auto M = parseAssemblyString(AssemblyStr, Error, Context);
1212   assert(M && "Bad assembly?");
1213 
1214   auto *F = M->getFunction("f");
1215   assert(F && "Bad assembly?");
1216 
1217   auto &BB = F->getEntryBlock();
1218 
1219   int Index = 0;
1220   for (auto &I : BB) {
1221     if (isa<ReturnInst>(&I))
1222       break;
1223     bool Poison = Data[Index].first.first;
1224     bool Undef = Data[Index].first.second;
1225     EXPECT_EQ(canCreatePoison(cast<Operator>(&I)), Poison)
1226         << "Incorrect answer of canCreatePoison at instruction " << Index
1227         << " = " << I;
1228     EXPECT_EQ(canCreateUndefOrPoison(cast<Operator>(&I)), Undef || Poison)
1229         << "Incorrect answer of canCreateUndef at instruction " << Index
1230         << " = " << I;
1231     Index++;
1232   }
1233 }
1234 
1235 TEST_F(ValueTrackingTest, computePtrAlignment) {
1236   parseAssembly("declare i1 @f_i1()\n"
1237                 "declare ptr @f_i8p()\n"
1238                 "declare void @llvm.assume(i1)\n"
1239                 "define void @test() {\n"
1240                 "  %A = call ptr @f_i8p()\n"
1241                 "  %cond = call i1 @f_i1()\n"
1242                 "  %CxtI = add i32 0, 0\n"
1243                 "  br i1 %cond, label %BB1, label %EXIT\n"
1244                 "BB1:\n"
1245                 "  %CxtI2 = add i32 0, 0\n"
1246                 "  %cond2 = call i1 @f_i1()\n"
1247                 "  call void @llvm.assume(i1 true) [ \"align\"(ptr %A, i64 16) ]\n"
1248                 "  br i1 %cond2, label %BB2, label %EXIT\n"
1249                 "BB2:\n"
1250                 "  %CxtI3 = add i32 0, 0\n"
1251                 "  ret void\n"
1252                 "EXIT:\n"
1253                 "  ret void\n"
1254                 "}");
1255   AssumptionCache AC(*F);
1256   DominatorTree DT(*F);
1257   const DataLayout &DL = M->getDataLayout();
1258   EXPECT_EQ(getKnownAlignment(A, DL, CxtI, &AC, &DT), Align(1));
1259   EXPECT_EQ(getKnownAlignment(A, DL, CxtI2, &AC, &DT), Align(1));
1260   EXPECT_EQ(getKnownAlignment(A, DL, CxtI3, &AC, &DT), Align(16));
1261 }
1262 
1263 TEST_F(ComputeKnownBitsTest, ComputeKnownBits) {
1264   parseAssembly(
1265       "define i32 @test(i32 %a, i32 %b) {\n"
1266       "  %ash = mul i32 %a, 8\n"
1267       "  %aad = add i32 %ash, 7\n"
1268       "  %aan = and i32 %aad, 4095\n"
1269       "  %bsh = shl i32 %b, 4\n"
1270       "  %bad = or i32 %bsh, 6\n"
1271       "  %ban = and i32 %bad, 4095\n"
1272       "  %A = mul i32 %aan, %ban\n"
1273       "  ret i32 %A\n"
1274       "}\n");
1275   expectKnownBits(/*zero*/ 4278190085u, /*one*/ 10u);
1276 }
1277 
1278 TEST_F(ComputeKnownBitsTest, ComputeKnownMulBits) {
1279   parseAssembly(
1280       "define i32 @test(i32 %a, i32 %b) {\n"
1281       "  %aa = shl i32 %a, 5\n"
1282       "  %bb = shl i32 %b, 5\n"
1283       "  %aaa = or i32 %aa, 24\n"
1284       "  %bbb = or i32 %bb, 28\n"
1285       "  %A = mul i32 %aaa, %bbb\n"
1286       "  ret i32 %A\n"
1287       "}\n");
1288   expectKnownBits(/*zero*/ 95u, /*one*/ 32u);
1289 }
1290 
1291 TEST_F(ComputeKnownFPClassTest, SelectPos0) {
1292   parseAssembly(
1293       "define float @test(i1 %cond) {\n"
1294       "  %A = select i1 %cond, float 0.0, float 0.0"
1295       "  ret float %A\n"
1296       "}\n");
1297   expectKnownFPClass(fcPosZero, false);
1298 }
1299 
1300 TEST_F(ComputeKnownFPClassTest, SelectNeg0) {
1301   parseAssembly(
1302       "define float @test(i1 %cond) {\n"
1303       "  %A = select i1 %cond, float -0.0, float -0.0"
1304       "  ret float %A\n"
1305       "}\n");
1306   expectKnownFPClass(fcNegZero, true);
1307 }
1308 
1309 TEST_F(ComputeKnownFPClassTest, SelectPosOrNeg0) {
1310   parseAssembly(
1311       "define float @test(i1 %cond) {\n"
1312       "  %A = select i1 %cond, float 0.0, float -0.0"
1313       "  ret float %A\n"
1314       "}\n");
1315   expectKnownFPClass(fcZero, std::nullopt);
1316 }
1317 
1318 TEST_F(ComputeKnownFPClassTest, SelectPosInf) {
1319   parseAssembly(
1320       "define float @test(i1 %cond) {\n"
1321       "  %A = select i1 %cond, float 0x7FF0000000000000, float 0x7FF0000000000000"
1322       "  ret float %A\n"
1323       "}\n");
1324   expectKnownFPClass(fcPosInf, false);
1325 }
1326 
1327 TEST_F(ComputeKnownFPClassTest, SelectNegInf) {
1328   parseAssembly(
1329       "define float @test(i1 %cond) {\n"
1330       "  %A = select i1 %cond, float 0xFFF0000000000000, float 0xFFF0000000000000"
1331       "  ret float %A\n"
1332       "}\n");
1333   expectKnownFPClass(fcNegInf, true);
1334 }
1335 
1336 TEST_F(ComputeKnownFPClassTest, SelectPosOrNegInf) {
1337   parseAssembly(
1338       "define float @test(i1 %cond) {\n"
1339       "  %A = select i1 %cond, float 0x7FF0000000000000, float 0xFFF0000000000000"
1340       "  ret float %A\n"
1341       "}\n");
1342   expectKnownFPClass(fcInf, std::nullopt);
1343 }
1344 
1345 TEST_F(ComputeKnownFPClassTest, SelectNNaN) {
1346   parseAssembly(
1347       "define float @test(i1 %cond, float %arg0, float %arg1) {\n"
1348       "  %A = select nnan i1 %cond, float %arg0, float %arg1"
1349       "  ret float %A\n"
1350       "}\n");
1351   expectKnownFPClass(~fcNan, std::nullopt);
1352 }
1353 
1354 TEST_F(ComputeKnownFPClassTest, SelectNInf) {
1355   parseAssembly(
1356       "define float @test(i1 %cond, float %arg0, float %arg1) {\n"
1357       "  %A = select ninf i1 %cond, float %arg0, float %arg1"
1358       "  ret float %A\n"
1359       "}\n");
1360   expectKnownFPClass(~fcInf, std::nullopt);
1361 }
1362 
1363 TEST_F(ComputeKnownFPClassTest, SelectNNaNNInf) {
1364   parseAssembly(
1365       "define float @test(i1 %cond, float %arg0, float %arg1) {\n"
1366       "  %A = select nnan ninf i1 %cond, float %arg0, float %arg1"
1367       "  ret float %A\n"
1368       "}\n");
1369   expectKnownFPClass(~(fcNan | fcInf), std::nullopt);
1370 }
1371 
1372 TEST_F(ComputeKnownFPClassTest, SelectNoFPClassArgUnionAll) {
1373   parseAssembly(
1374       "define float @test(i1 %cond, float nofpclass(snan ninf nsub pzero pnorm) %arg0, float nofpclass(qnan nnorm nzero psub pinf) %arg1) {\n"
1375       "  %A = select i1 %cond, float %arg0, float %arg1"
1376       "  ret float %A\n"
1377       "}\n");
1378   expectKnownFPClass(fcAllFlags, std::nullopt);
1379 }
1380 
1381 TEST_F(ComputeKnownFPClassTest, SelectNoFPClassArgNoNan) {
1382   parseAssembly(
1383       "define float @test(i1 %cond, float nofpclass(nan) %arg0, float nofpclass(nan) %arg1) {\n"
1384       "  %A = select i1 %cond, float %arg0, float %arg1"
1385       "  ret float %A\n"
1386       "}\n");
1387   expectKnownFPClass(~fcNan, std::nullopt);
1388 }
1389 
1390 TEST_F(ComputeKnownFPClassTest, SelectNoFPClassArgNoPInf) {
1391   parseAssembly(
1392       "define float @test(i1 %cond, float nofpclass(inf) %arg0, float nofpclass(pinf) %arg1) {\n"
1393       "  %A = select i1 %cond, float %arg0, float %arg1"
1394       "  ret float %A\n"
1395       "}\n");
1396   expectKnownFPClass(~fcPosInf, std::nullopt);
1397 }
1398 
1399 TEST_F(ComputeKnownFPClassTest, SelectNoFPClassArgNoNInf) {
1400   parseAssembly(
1401       "define float @test(i1 %cond, float nofpclass(ninf) %arg0, float nofpclass(inf) %arg1) {\n"
1402       "  %A = select i1 %cond, float %arg0, float %arg1"
1403       "  ret float %A\n"
1404       "}\n");
1405   expectKnownFPClass(~fcNegInf, std::nullopt);
1406 }
1407 
1408 TEST_F(ComputeKnownFPClassTest, SelectNoFPClassCallSiteNoNan) {
1409   parseAssembly(
1410       "declare float @func()\n"
1411       "define float @test() {\n"
1412       "  %A = call nofpclass(nan) float @func()\n"
1413       "  ret float %A\n"
1414       "}\n");
1415   expectKnownFPClass(~fcNan, std::nullopt);
1416 }
1417 
1418 TEST_F(ComputeKnownFPClassTest, SelectNoFPClassCallSiteNoZeros) {
1419   parseAssembly(
1420       "declare float @func()\n"
1421       "define float @test() {\n"
1422       "  %A = call nofpclass(zero) float @func()\n"
1423       "  ret float %A\n"
1424       "}\n");
1425   expectKnownFPClass(~fcZero, std::nullopt);
1426 }
1427 
1428 TEST_F(ComputeKnownFPClassTest, SelectNoFPClassDeclarationNoNan) {
1429   parseAssembly(
1430       "declare nofpclass(nan) float @no_nans()\n"
1431       "define float @test() {\n"
1432       "  %A = call float @no_nans()\n"
1433       "  ret float %A\n"
1434       "}\n");
1435   expectKnownFPClass(~fcNan, std::nullopt);
1436 }
1437 
1438 // Check nofpclass + ninf works on a callsite
1439 TEST_F(ComputeKnownFPClassTest, SelectNoFPClassCallSiteNoZerosNInfFlags) {
1440   parseAssembly(
1441       "declare float @func()\n"
1442       "define float @test() {\n"
1443       "  %A = call ninf nofpclass(zero) float @func()\n"
1444       "  ret float %A\n"
1445       "}\n");
1446   expectKnownFPClass(~(fcZero | fcInf), std::nullopt);
1447 }
1448 
1449 TEST_F(ComputeKnownFPClassTest, FNegNInf) {
1450   parseAssembly(
1451       "define float @test(float %arg) {\n"
1452       "  %A = fneg ninf float %arg"
1453       "  ret float %A\n"
1454       "}\n");
1455   expectKnownFPClass(~fcInf, std::nullopt);
1456 }
1457 
1458 TEST_F(ComputeKnownFPClassTest, FabsUnknown) {
1459   parseAssembly(
1460       "declare float @llvm.fabs.f32(float)"
1461       "define float @test(float %arg) {\n"
1462       "  %A = call float @llvm.fabs.f32(float %arg)"
1463       "  ret float %A\n"
1464       "}\n");
1465   expectKnownFPClass(fcPositive | fcNan, false);
1466 }
1467 
1468 TEST_F(ComputeKnownFPClassTest, FNegFabsUnknown) {
1469   parseAssembly(
1470       "declare float @llvm.fabs.f32(float)"
1471       "define float @test(float %arg) {\n"
1472       "  %fabs = call float @llvm.fabs.f32(float %arg)"
1473       "  %A = fneg float %fabs"
1474       "  ret float %A\n"
1475       "}\n");
1476   expectKnownFPClass(fcNegative | fcNan, true);
1477 }
1478 
1479 TEST_F(ComputeKnownFPClassTest, NegFabsNInf) {
1480   parseAssembly(
1481       "declare float @llvm.fabs.f32(float)"
1482       "define float @test(float %arg) {\n"
1483       "  %fabs = call ninf float @llvm.fabs.f32(float %arg)"
1484       "  %A = fneg float %fabs"
1485       "  ret float %A\n"
1486       "}\n");
1487   expectKnownFPClass((fcNegative & ~fcNegInf) | fcNan, true);
1488 }
1489 
1490 TEST_F(ComputeKnownFPClassTest, FNegFabsNNaN) {
1491   parseAssembly(
1492       "declare float @llvm.fabs.f32(float)"
1493       "define float @test(float %arg) {\n"
1494       "  %fabs = call nnan float @llvm.fabs.f32(float %arg)"
1495       "  %A = fneg float %fabs"
1496       "  ret float %A\n"
1497       "}\n");
1498   expectKnownFPClass(fcNegative, true);
1499 }
1500 
1501 TEST_F(ComputeKnownFPClassTest, CopySignNNanSrc0) {
1502   parseAssembly(
1503       "declare float @llvm.fabs.f32(float)\n"
1504       "declare float @llvm.copysign.f32(float, float)\n"
1505       "define float @test(float %arg0, float %arg1) {\n"
1506       "  %fabs = call nnan float @llvm.fabs.f32(float %arg0)"
1507       "  %A = call float @llvm.copysign.f32(float %fabs, float %arg1)"
1508       "  ret float %A\n"
1509       "}\n");
1510   expectKnownFPClass(~fcNan, std::nullopt);
1511 }
1512 
1513 TEST_F(ComputeKnownFPClassTest, CopySignNInfSrc0_NegSign) {
1514   parseAssembly(
1515       "declare float @llvm.log.f32(float)\n"
1516       "declare float @llvm.copysign.f32(float, float)\n"
1517       "define float @test(float %arg0, float %arg1) {\n"
1518       "  %ninf = call ninf float @llvm.log.f32(float %arg0)"
1519       "  %A = call float @llvm.copysign.f32(float %ninf, float -1.0)"
1520       "  ret float %A\n"
1521       "}\n");
1522   expectKnownFPClass(fcNegFinite | fcNan, true);
1523 }
1524 
1525 TEST_F(ComputeKnownFPClassTest, CopySignNInfSrc0_PosSign) {
1526   parseAssembly(
1527       "declare float @llvm.sqrt.f32(float)\n"
1528       "declare float @llvm.copysign.f32(float, float)\n"
1529       "define float @test(float %arg0, float %arg1) {\n"
1530       "  %ninf = call ninf float @llvm.sqrt.f32(float %arg0)"
1531       "  %A = call float @llvm.copysign.f32(float %ninf, float 1.0)"
1532       "  ret float %A\n"
1533       "}\n");
1534   expectKnownFPClass(fcPosFinite | fcNan, false);
1535 }
1536 
1537 TEST_F(ComputeKnownFPClassTest, UIToFP) {
1538   parseAssembly(
1539       "define float @test(i32 %arg0, i16 %arg1) {\n"
1540       "  %A = uitofp i32 %arg0 to float"
1541       "  %A2 = uitofp i16 %arg1 to half"
1542       "  ret float %A\n"
1543       "}\n");
1544   expectKnownFPClass(fcPosFinite & ~fcSubnormal, false, A);
1545   expectKnownFPClass(fcPositive & ~fcSubnormal, false, A2);
1546 }
1547 
1548 TEST_F(ComputeKnownFPClassTest, SIToFP) {
1549   parseAssembly(
1550       "define float @test(i32 %arg0, i16 %arg1, i17 %arg2) {\n"
1551       "  %A = sitofp i32 %arg0 to float"
1552       "  %A2 = sitofp i16 %arg1 to half"
1553       "  %A3 = sitofp i17 %arg2 to half"
1554       "  ret float %A\n"
1555       "}\n");
1556   expectKnownFPClass(fcFinite & ~fcNegZero & ~fcSubnormal, std::nullopt, A);
1557   expectKnownFPClass(fcFinite & ~fcNegZero & ~fcSubnormal, std::nullopt, A2);
1558   expectKnownFPClass(~(fcNan | fcNegZero | fcSubnormal), std::nullopt, A3);
1559 }
1560 
1561 TEST_F(ComputeKnownFPClassTest, FAdd) {
1562   parseAssembly(
1563       "define float @test(float nofpclass(nan inf) %nnan.ninf, float nofpclass(nan) %nnan, float nofpclass(qnan) %no.qnan, float %unknown) {\n"
1564       "  %A = fadd float %nnan, %nnan.ninf"
1565       "  %A2 = fadd float %nnan.ninf, %nnan"
1566       "  %A3 = fadd float %nnan.ninf, %unknown"
1567       "  %A4 = fadd float %nnan.ninf, %no.qnan"
1568       "  %A5 = fadd float %nnan, %nnan"
1569       "  ret float %A\n"
1570       "}\n");
1571   expectKnownFPClass(fcFinite | fcInf, std::nullopt, A);
1572   expectKnownFPClass(fcFinite | fcInf, std::nullopt, A2);
1573   expectKnownFPClass(fcAllFlags, std::nullopt, A3);
1574   expectKnownFPClass(fcAllFlags, std::nullopt, A4);
1575   expectKnownFPClass(fcAllFlags, std::nullopt, A5);
1576 }
1577 
1578 TEST_F(ComputeKnownFPClassTest, FSub) {
1579   parseAssembly(
1580       "define float @test(float nofpclass(nan inf) %nnan.ninf, float nofpclass(nan) %nnan, float nofpclass(qnan) %no.qnan, float %unknown) {\n"
1581       "  %A = fsub float %nnan, %nnan.ninf"
1582       "  %A2 = fsub float %nnan.ninf, %nnan"
1583       "  %A3 = fsub float %nnan.ninf, %unknown"
1584       "  %A4 = fsub float %nnan.ninf, %no.qnan"
1585       "  %A5 = fsub float %nnan, %nnan"
1586       "  ret float %A\n"
1587       "}\n");
1588   expectKnownFPClass(fcFinite | fcInf, std::nullopt, A);
1589   expectKnownFPClass(fcFinite | fcInf, std::nullopt, A2);
1590   expectKnownFPClass(fcAllFlags, std::nullopt, A3);
1591   expectKnownFPClass(fcAllFlags, std::nullopt, A4);
1592   expectKnownFPClass(fcAllFlags, std::nullopt, A5);
1593 }
1594 
1595 TEST_F(ComputeKnownFPClassTest, FMul) {
1596   parseAssembly(
1597       "define float @test(float nofpclass(nan inf) %nnan.ninf0, float nofpclass(nan inf) %nnan.ninf1, float nofpclass(nan) %nnan, float nofpclass(qnan) %no.qnan, float %unknown) {\n"
1598       "  %A = fmul float %nnan.ninf0, %nnan.ninf1"
1599       "  %A2 = fmul float %nnan.ninf0, %nnan"
1600       "  %A3 = fmul float %nnan, %nnan.ninf0"
1601       "  %A4 = fmul float %nnan.ninf0, %no.qnan"
1602       "  %A5 = fmul float %nnan, %nnan"
1603       "  ret float %A\n"
1604       "}\n");
1605   expectKnownFPClass(fcFinite | fcInf, std::nullopt, A);
1606   expectKnownFPClass(fcAllFlags, std::nullopt, A2);
1607   expectKnownFPClass(fcAllFlags, std::nullopt, A3);
1608   expectKnownFPClass(fcAllFlags, std::nullopt, A4);
1609   expectKnownFPClass(fcPositive | fcNan, std::nullopt, A5);
1610 }
1611 
1612 TEST_F(ComputeKnownFPClassTest, FMulNoZero) {
1613   parseAssembly(
1614       "define float @test(float nofpclass(zero) %no.zero, float nofpclass(zero nan) %no.zero.nan0, float nofpclass(zero nan) %no.zero.nan1, float nofpclass(nzero nan) %no.negzero.nan, float nofpclass(pzero nan) %no.poszero.nan, float nofpclass(inf nan) %no.inf.nan, float nofpclass(inf) %no.inf, float nofpclass(nan) %no.nan) {\n"
1615       "  %A = fmul float %no.zero.nan0, %no.zero.nan1"
1616       "  %A2 = fmul float %no.zero, %no.zero"
1617       "  %A3 = fmul float %no.poszero.nan, %no.zero.nan0"
1618       "  %A4 = fmul float %no.nan, %no.zero"
1619       "  %A5 = fmul float %no.zero, %no.inf"
1620       "  %A6 = fmul float %no.zero.nan0, %no.nan"
1621       "  %A7 = fmul float %no.nan, %no.zero.nan0"
1622       "  ret float %A\n"
1623       "}\n");
1624   expectKnownFPClass(fcFinite | fcInf, std::nullopt, A);
1625   expectKnownFPClass(fcPositive | fcNan, std::nullopt, A2);
1626   expectKnownFPClass(fcAllFlags, std::nullopt, A3);
1627   expectKnownFPClass(fcAllFlags, std::nullopt, A4);
1628   expectKnownFPClass(fcAllFlags, std::nullopt, A5);
1629   expectKnownFPClass(fcAllFlags, std::nullopt, A6);
1630   expectKnownFPClass(fcAllFlags, std::nullopt, A7);
1631 }
1632 
1633 TEST_F(ComputeKnownFPClassTest, Phi) {
1634   parseAssembly(
1635       "define float @test(i1 %cond, float nofpclass(nan inf) %arg0, float nofpclass(nan) %arg1) {\n"
1636       "entry:\n"
1637       "  br i1 %cond, label %bb0, label %bb1\n"
1638       "bb0:\n"
1639       "  br label %ret\n"
1640       "bb1:\n"
1641       "  br label %ret\n"
1642       "ret:\n"
1643       "  %A = phi float [ %arg0, %bb0 ],  [ %arg1, %bb1 ]\n"
1644       "  ret float %A\n"
1645       "}\n");
1646   expectKnownFPClass(~fcNan, std::nullopt);
1647 }
1648 
1649 TEST_F(ComputeKnownFPClassTest, PhiKnownSignFalse) {
1650   parseAssembly(
1651       "declare float @llvm.fabs.f32(float)"
1652       "define float @test(i1 %cond, float nofpclass(nan) %arg0, float nofpclass(nan) %arg1) {\n"
1653       "entry:\n"
1654       "  br i1 %cond, label %bb0, label %bb1\n"
1655       "bb0:\n"
1656       "  %fabs.arg0 = call float @llvm.fabs.f32(float %arg0)\n"
1657       "  br label %ret\n"
1658       "bb1:\n"
1659       "  %fabs.arg1 = call float @llvm.fabs.f32(float %arg1)\n"
1660       "  br label %ret\n"
1661       "ret:\n"
1662       "  %A = phi float [ %fabs.arg0, %bb0 ],  [ %fabs.arg1, %bb1 ]\n"
1663       "  ret float %A\n"
1664       "}\n");
1665   expectKnownFPClass(fcPositive, false);
1666 }
1667 
1668 TEST_F(ComputeKnownFPClassTest, PhiKnownSignTrue) {
1669   parseAssembly(
1670       "declare float @llvm.fabs.f32(float)"
1671       "define float @test(i1 %cond, float nofpclass(nan) %arg0, float %arg1) {\n"
1672       "entry:\n"
1673       "  br i1 %cond, label %bb0, label %bb1\n"
1674       "bb0:\n"
1675       "  %fabs.arg0 = call float @llvm.fabs.f32(float %arg0)\n"
1676       "  %fneg.fabs.arg0 = fneg float %fabs.arg0\n"
1677       "  br label %ret\n"
1678       "bb1:\n"
1679       "  %fabs.arg1 = call float @llvm.fabs.f32(float %arg1)\n"
1680       "  %fneg.fabs.arg1 = fneg float %fabs.arg1\n"
1681       "  br label %ret\n"
1682       "ret:\n"
1683       "  %A = phi float [ %fneg.fabs.arg0, %bb0 ],  [ %fneg.fabs.arg1, %bb1 ]\n"
1684       "  ret float %A\n"
1685       "}\n");
1686   expectKnownFPClass(fcNegative | fcNan, true);
1687 }
1688 
1689 TEST_F(ComputeKnownFPClassTest, UnreachablePhi) {
1690   parseAssembly(
1691       "define float @test(float %arg) {\n"
1692       "entry:\n"
1693       "  ret float 0.0\n"
1694       "unreachable:\n"
1695       "  %A = phi float\n"
1696       "  ret float %A\n"
1697       "}\n");
1698   expectKnownFPClass(fcAllFlags, std::nullopt);
1699 }
1700 
1701 TEST_F(ComputeKnownFPClassTest, SelfPhiOnly) {
1702   parseAssembly(
1703       "define float @test(float %arg) {\n"
1704       "entry:\n"
1705       "  ret float 0.0\n"
1706       "loop:\n"
1707       "  %A = phi float [ %A, %loop ]\n"
1708       "  br label %loop\n"
1709       "}\n");
1710   expectKnownFPClass(fcAllFlags, std::nullopt);
1711 }
1712 
1713 TEST_F(ComputeKnownFPClassTest, SelfPhiFirstArg) {
1714   parseAssembly(
1715       "define float @test(i1 %cond, float nofpclass(inf) %arg) {\n"
1716       "entry:\n"
1717       "  br i1 %cond, label %loop, label %ret\n"
1718       "loop:\n"
1719       "  %A = phi float [ %arg, %entry ], [ %A, %loop ]\n"
1720       "  br label %loop\n"
1721       "ret:\n"
1722       "  ret float %A"
1723       "}\n");
1724   expectKnownFPClass(~fcInf, std::nullopt);
1725 }
1726 
1727 TEST_F(ComputeKnownFPClassTest, SelfPhiSecondArg) {
1728   parseAssembly(
1729       "define float @test(i1 %cond, float nofpclass(inf) %arg) {\n"
1730       "entry:\n"
1731       "  br i1 %cond, label %loop, label %ret\n"
1732       "loop:\n"
1733       "  %A = phi float [ %A, %loop ], [ %arg, %entry ]\n"
1734       "  br label %loop\n"
1735       "ret:\n"
1736       "  ret float %A"
1737       "}\n");
1738   expectKnownFPClass(~fcInf, std::nullopt);
1739 }
1740 
1741 TEST_F(ComputeKnownFPClassTest, CannotBeOrderedLessThanZero) {
1742   parseAssembly("define float @test(float %arg) {\n"
1743                 "  %A = fmul float %arg, %arg"
1744                 "  ret float %A\n"
1745                 "}\n");
1746 
1747   Type *FPTy = Type::getDoubleTy(M->getContext());
1748   const DataLayout &DL = M->getDataLayout();
1749 
1750   EXPECT_TRUE(
1751       computeKnownFPClass(ConstantFP::getZero(FPTy, /*Negative=*/false), DL)
1752           .cannotBeOrderedLessThanZero());
1753   EXPECT_TRUE(
1754       computeKnownFPClass(ConstantFP::getZero(FPTy, /*Negative=*/true), DL)
1755           .cannotBeOrderedLessThanZero());
1756 
1757   EXPECT_TRUE(computeKnownFPClass(ConstantFP::getInfinity(FPTy, false), DL)
1758                   .cannotBeOrderedLessThanZero());
1759   EXPECT_FALSE(computeKnownFPClass(ConstantFP::getInfinity(FPTy, true), DL)
1760                    .cannotBeOrderedLessThanZero());
1761 
1762   EXPECT_TRUE(computeKnownFPClass(ConstantFP::get(FPTy, 1.0), DL)
1763                   .cannotBeOrderedLessThanZero());
1764   EXPECT_FALSE(computeKnownFPClass(ConstantFP::get(FPTy, -1.0), DL)
1765                    .cannotBeOrderedLessThanZero());
1766 
1767   EXPECT_TRUE(
1768       computeKnownFPClass(
1769           ConstantFP::get(FPTy, APFloat::getSmallest(FPTy->getFltSemantics(),
1770                                                      /*Negative=*/false)),
1771           DL)
1772           .cannotBeOrderedLessThanZero());
1773   EXPECT_FALSE(
1774       computeKnownFPClass(
1775           ConstantFP::get(FPTy, APFloat::getSmallest(FPTy->getFltSemantics(),
1776                                                      /*Negative=*/true)),
1777           DL)
1778           .cannotBeOrderedLessThanZero());
1779 
1780   EXPECT_TRUE(
1781       computeKnownFPClass(ConstantFP::getQNaN(FPTy, /*Negative=*/false), DL)
1782           .cannotBeOrderedLessThanZero());
1783   EXPECT_TRUE(
1784       computeKnownFPClass(ConstantFP::getQNaN(FPTy, /*Negative=*/true), DL)
1785           .cannotBeOrderedLessThanZero());
1786   EXPECT_TRUE(
1787       computeKnownFPClass(ConstantFP::getSNaN(FPTy, /*Negative=*/false), DL)
1788           .cannotBeOrderedLessThanZero());
1789   EXPECT_TRUE(
1790       computeKnownFPClass(ConstantFP::getSNaN(FPTy, /*Negative=*/true), DL)
1791           .cannotBeOrderedLessThanZero());
1792 }
1793 
1794 TEST_F(ComputeKnownFPClassTest, FCmpToClassTest_OrdNan) {
1795   parseAssembly("define i1 @test(double %arg) {\n"
1796                 "  %A = fcmp ord double %arg, 0x7FF8000000000000"
1797                 "  %A2 = fcmp uno double %arg, 0x7FF8000000000000"
1798                 "  %A3 = fcmp oeq double %arg, 0x7FF8000000000000"
1799                 "  %A4 = fcmp ueq double %arg, 0x7FF8000000000000"
1800                 "  ret i1 %A\n"
1801                 "}\n");
1802 
1803   auto [OrdVal, OrdClass] = fcmpToClassTest(
1804       CmpInst::FCMP_ORD, *A->getFunction(), A->getOperand(0), A->getOperand(1));
1805   EXPECT_EQ(A->getOperand(0), OrdVal);
1806   EXPECT_EQ(fcNone, OrdClass);
1807 
1808   auto [UnordVal, UnordClass] =
1809       fcmpToClassTest(CmpInst::FCMP_UNO, *A2->getFunction(), A2->getOperand(0),
1810                       A2->getOperand(1));
1811   EXPECT_EQ(A2->getOperand(0), UnordVal);
1812   EXPECT_EQ(fcAllFlags, UnordClass);
1813 
1814   auto [OeqVal, OeqClass] =
1815       fcmpToClassTest(CmpInst::FCMP_OEQ, *A3->getFunction(), A3->getOperand(0),
1816                       A3->getOperand(1));
1817   EXPECT_EQ(A3->getOperand(0), OeqVal);
1818   EXPECT_EQ(fcNone, OeqClass);
1819 
1820   auto [UeqVal, UeqClass] =
1821       fcmpToClassTest(CmpInst::FCMP_UEQ, *A3->getFunction(), A3->getOperand(0),
1822                       A3->getOperand(1));
1823   EXPECT_EQ(A3->getOperand(0), UeqVal);
1824   EXPECT_EQ(fcAllFlags, UeqClass);
1825 }
1826 
1827 TEST_F(ComputeKnownFPClassTest, FCmpToClassTest_NInf) {
1828   parseAssembly("define i1 @test(double %arg) {\n"
1829                 "  %A = fcmp olt double %arg, 0xFFF0000000000000"
1830                 "  %A2 = fcmp uge double %arg, 0xFFF0000000000000"
1831                 "  %A3 = fcmp ogt double %arg, 0xFFF0000000000000"
1832                 "  %A4 = fcmp ule double %arg, 0xFFF0000000000000"
1833                 "  ret i1 %A\n"
1834                 "}\n");
1835 
1836   auto [OltVal, OltClass] = fcmpToClassTest(
1837       CmpInst::FCMP_OLT, *A->getFunction(), A->getOperand(0), A->getOperand(1));
1838   EXPECT_EQ(A->getOperand(0), OltVal);
1839   EXPECT_EQ(fcNone, OltClass);
1840 
1841   auto [UgeVal, UgeClass] =
1842       fcmpToClassTest(CmpInst::FCMP_UGE, *A2->getFunction(), A2->getOperand(0),
1843                       A2->getOperand(1));
1844   EXPECT_EQ(A2->getOperand(0), UgeVal);
1845   EXPECT_EQ(fcAllFlags, UgeClass);
1846 
1847   auto [OgtVal, OgtClass] =
1848       fcmpToClassTest(CmpInst::FCMP_OGT, *A3->getFunction(), A3->getOperand(0),
1849                       A3->getOperand(1));
1850   EXPECT_EQ(nullptr, OgtVal);
1851   EXPECT_EQ(fcAllFlags, OgtClass);
1852 
1853   auto [UleVal, UleClass] =
1854       fcmpToClassTest(CmpInst::FCMP_ULE, *A4->getFunction(), A4->getOperand(0),
1855                       A4->getOperand(1));
1856   EXPECT_EQ(nullptr, UleVal);
1857   EXPECT_EQ(fcAllFlags, UleClass);
1858 }
1859 
1860 TEST_F(ComputeKnownFPClassTest, FCmpToClassTest_PInf) {
1861   parseAssembly("define i1 @test(double %arg) {\n"
1862                 "  %A = fcmp ogt double %arg, 0x7FF0000000000000"
1863                 "  %A2 = fcmp ule double %arg, 0x7FF0000000000000"
1864                 "  %A3 = fcmp ole double %arg, 0x7FF0000000000000"
1865                 "  %A4 = fcmp ugt double %arg, 0x7FF0000000000000"
1866                 "  ret i1 %A\n"
1867                 "}\n");
1868 
1869   auto [OgtVal, OgtClass] = fcmpToClassTest(
1870       CmpInst::FCMP_OGT, *A->getFunction(), A->getOperand(0), A->getOperand(1));
1871   EXPECT_EQ(A->getOperand(0), OgtVal);
1872   EXPECT_EQ(fcNone, OgtClass);
1873 
1874   auto [UleVal, UleClass] =
1875       fcmpToClassTest(CmpInst::FCMP_ULE, *A2->getFunction(), A2->getOperand(0),
1876                       A2->getOperand(1));
1877   EXPECT_EQ(A2->getOperand(0), UleVal);
1878   EXPECT_EQ(fcAllFlags, UleClass);
1879 
1880   auto [OleVal, OleClass] =
1881       fcmpToClassTest(CmpInst::FCMP_OLE, *A3->getFunction(), A3->getOperand(0),
1882                       A3->getOperand(1));
1883   EXPECT_EQ(nullptr, OleVal);
1884   EXPECT_EQ(fcAllFlags, OleClass);
1885 
1886   auto [UgtVal, UgtClass] =
1887       fcmpToClassTest(CmpInst::FCMP_UGT, *A4->getFunction(), A4->getOperand(0),
1888                       A4->getOperand(1));
1889   EXPECT_EQ(nullptr, UgtVal);
1890   EXPECT_EQ(fcAllFlags, UgtClass);
1891 }
1892 
1893 TEST_F(ComputeKnownFPClassTest, SqrtNszSignBit) {
1894   parseAssembly(
1895       "declare float @llvm.sqrt.f32(float)\n"
1896       "define float @test(float %arg, float nofpclass(nan) %arg.nnan) {\n"
1897       "  %A = call float @llvm.sqrt.f32(float %arg)\n"
1898       "  %A2 = call nsz float @llvm.sqrt.f32(float %arg)\n"
1899       "  %A3 = call float @llvm.sqrt.f32(float %arg.nnan)\n"
1900       "  %A4 = call nsz float @llvm.sqrt.f32(float %arg.nnan)\n"
1901       "  ret float %A\n"
1902       "}\n");
1903 
1904   const FPClassTest SqrtMask = fcPositive | fcNegZero | fcNan;
1905   const FPClassTest NszSqrtMask = fcPositive | fcNan;
1906 
1907   {
1908     KnownFPClass UseInstrInfo =
1909         computeKnownFPClass(A, M->getDataLayout(), fcAllFlags, 0, nullptr,
1910                             nullptr, nullptr, nullptr, /*UseInstrInfo=*/true);
1911     EXPECT_EQ(SqrtMask, UseInstrInfo.KnownFPClasses);
1912     EXPECT_EQ(std::nullopt, UseInstrInfo.SignBit);
1913 
1914     KnownFPClass NoUseInstrInfo =
1915         computeKnownFPClass(A, M->getDataLayout(), fcAllFlags, 0, nullptr,
1916                             nullptr, nullptr, nullptr, /*UseInstrInfo=*/false);
1917     EXPECT_EQ(SqrtMask, NoUseInstrInfo.KnownFPClasses);
1918     EXPECT_EQ(std::nullopt, NoUseInstrInfo.SignBit);
1919   }
1920 
1921   {
1922     KnownFPClass UseInstrInfoNSZ =
1923         computeKnownFPClass(A2, M->getDataLayout(), fcAllFlags, 0, nullptr,
1924                             nullptr, nullptr, nullptr, /*UseInstrInfo=*/true);
1925     EXPECT_EQ(NszSqrtMask, UseInstrInfoNSZ.KnownFPClasses);
1926     EXPECT_EQ(std::nullopt, UseInstrInfoNSZ.SignBit);
1927 
1928     KnownFPClass NoUseInstrInfoNSZ =
1929         computeKnownFPClass(A2, M->getDataLayout(), fcAllFlags, 0, nullptr,
1930                             nullptr, nullptr, nullptr, /*UseInstrInfo=*/false);
1931     EXPECT_EQ(SqrtMask, NoUseInstrInfoNSZ.KnownFPClasses);
1932     EXPECT_EQ(std::nullopt, NoUseInstrInfoNSZ.SignBit);
1933   }
1934 
1935   {
1936     KnownFPClass UseInstrInfoNoNan =
1937         computeKnownFPClass(A3, M->getDataLayout(), fcAllFlags, 0, nullptr,
1938                             nullptr, nullptr, nullptr, /*UseInstrInfo=*/true);
1939     EXPECT_EQ(fcPositive | fcNegZero | fcQNan,
1940               UseInstrInfoNoNan.KnownFPClasses);
1941     EXPECT_EQ(std::nullopt, UseInstrInfoNoNan.SignBit);
1942 
1943     KnownFPClass NoUseInstrInfoNoNan =
1944         computeKnownFPClass(A3, M->getDataLayout(), fcAllFlags, 0, nullptr,
1945                             nullptr, nullptr, nullptr, /*UseInstrInfo=*/false);
1946     EXPECT_EQ(fcPositive | fcNegZero | fcQNan,
1947               NoUseInstrInfoNoNan.KnownFPClasses);
1948     EXPECT_EQ(std::nullopt, NoUseInstrInfoNoNan.SignBit);
1949   }
1950 
1951   {
1952     KnownFPClass UseInstrInfoNSZNoNan =
1953         computeKnownFPClass(A4, M->getDataLayout(), fcAllFlags, 0, nullptr,
1954                             nullptr, nullptr, nullptr, /*UseInstrInfo=*/true);
1955     EXPECT_EQ(fcPositive | fcQNan, UseInstrInfoNSZNoNan.KnownFPClasses);
1956     EXPECT_EQ(false, UseInstrInfoNSZNoNan.SignBit);
1957 
1958     KnownFPClass NoUseInstrInfoNSZNoNan =
1959         computeKnownFPClass(A4, M->getDataLayout(), fcAllFlags, 0, nullptr,
1960                             nullptr, nullptr, nullptr, /*UseInstrInfo=*/false);
1961     EXPECT_EQ(fcPositive | fcNegZero | fcQNan,
1962               NoUseInstrInfoNSZNoNan.KnownFPClasses);
1963     EXPECT_EQ(std::nullopt, NoUseInstrInfoNSZNoNan.SignBit);
1964   }
1965 }
1966 
1967 TEST_F(ValueTrackingTest, isNonZeroRecurrence) {
1968   parseAssembly(R"(
1969     define i1 @test(i8 %n, i8 %r) {
1970     entry:
1971       br label %loop
1972     loop:
1973       %p = phi i8 [ -1, %entry ], [ %next, %loop ]
1974       %next = add nsw i8 %p, -1
1975       %cmp1 = icmp eq i8 %p, %n
1976       br i1 %cmp1, label %exit, label %loop
1977     exit:
1978       %A = or i8 %p, %r
1979       %CxtI = icmp eq i8 %A, 0
1980       ret i1 %CxtI
1981     }
1982   )");
1983   const DataLayout &DL = M->getDataLayout();
1984   AssumptionCache AC(*F);
1985   EXPECT_TRUE(isKnownNonZero(A, DL, 0, &AC, CxtI));
1986 }
1987 
1988 TEST_F(ValueTrackingTest, KnownNonZeroFromDomCond) {
1989   parseAssembly(R"(
1990     declare ptr @f_i8()
1991     define void @test(i1 %c) {
1992       %A = call ptr @f_i8()
1993       %B = call ptr @f_i8()
1994       %c1 = icmp ne ptr %A, null
1995       %cond = and i1 %c1, %c
1996       br i1 %cond, label %T, label %Q
1997     T:
1998       %CxtI = add i32 0, 0
1999       ret void
2000     Q:
2001       %CxtI2 = add i32 0, 0
2002       ret void
2003     }
2004   )");
2005   AssumptionCache AC(*F);
2006   DominatorTree DT(*F);
2007   const DataLayout &DL = M->getDataLayout();
2008   EXPECT_EQ(isKnownNonZero(A, DL, 0, &AC, CxtI, &DT), true);
2009   EXPECT_EQ(isKnownNonZero(A, DL, 0, &AC, CxtI2, &DT), false);
2010 }
2011 
2012 TEST_F(ValueTrackingTest, KnownNonZeroFromDomCond2) {
2013   parseAssembly(R"(
2014     declare ptr @f_i8()
2015     define void @test(i1 %c) {
2016       %A = call ptr @f_i8()
2017       %B = call ptr @f_i8()
2018       %c1 = icmp ne ptr %A, null
2019       %cond = select i1 %c, i1 %c1, i1 false
2020       br i1 %cond, label %T, label %Q
2021     T:
2022       %CxtI = add i32 0, 0
2023       ret void
2024     Q:
2025       %CxtI2 = add i32 0, 0
2026       ret void
2027     }
2028   )");
2029   AssumptionCache AC(*F);
2030   DominatorTree DT(*F);
2031   const DataLayout &DL = M->getDataLayout();
2032   EXPECT_EQ(isKnownNonZero(A, DL, 0, &AC, CxtI, &DT), true);
2033   EXPECT_EQ(isKnownNonZero(A, DL, 0, &AC, CxtI2, &DT), false);
2034 }
2035 
2036 TEST_F(ValueTrackingTest, IsImpliedConditionAnd) {
2037   parseAssembly(R"(
2038     define void @test(i32 %x, i32 %y) {
2039       %c1 = icmp ult i32 %x, 10
2040       %c2 = icmp ult i32 %y, 15
2041       %A = and i1 %c1, %c2
2042       ; x < 10 /\ y < 15
2043       %A2 = icmp ult i32 %x, 20
2044       %A3 = icmp uge i32 %y, 20
2045       %A4 = icmp ult i32 %x, 5
2046       ret void
2047     }
2048   )");
2049   const DataLayout &DL = M->getDataLayout();
2050   EXPECT_EQ(isImpliedCondition(A, A2, DL), true);
2051   EXPECT_EQ(isImpliedCondition(A, A3, DL), false);
2052   EXPECT_EQ(isImpliedCondition(A, A4, DL), std::nullopt);
2053 }
2054 
2055 TEST_F(ValueTrackingTest, IsImpliedConditionAnd2) {
2056   parseAssembly(R"(
2057     define void @test(i32 %x, i32 %y) {
2058       %c1 = icmp ult i32 %x, 10
2059       %c2 = icmp ult i32 %y, 15
2060       %A = select i1 %c1, i1 %c2, i1 false
2061       ; x < 10 /\ y < 15
2062       %A2 = icmp ult i32 %x, 20
2063       %A3 = icmp uge i32 %y, 20
2064       %A4 = icmp ult i32 %x, 5
2065       ret void
2066     }
2067   )");
2068   const DataLayout &DL = M->getDataLayout();
2069   EXPECT_EQ(isImpliedCondition(A, A2, DL), true);
2070   EXPECT_EQ(isImpliedCondition(A, A3, DL), false);
2071   EXPECT_EQ(isImpliedCondition(A, A4, DL), std::nullopt);
2072 }
2073 
2074 TEST_F(ValueTrackingTest, IsImpliedConditionAndVec) {
2075   parseAssembly(R"(
2076     define void @test(<2 x i8> %x, <2 x i8> %y) {
2077       %A = icmp ult <2 x i8> %x, %y
2078       %A2 = icmp ule <2 x i8> %x, %y
2079       ret void
2080     }
2081   )");
2082   const DataLayout &DL = M->getDataLayout();
2083   EXPECT_EQ(isImpliedCondition(A, A2, DL), true);
2084 }
2085 
2086 TEST_F(ValueTrackingTest, IsImpliedConditionOr) {
2087   parseAssembly(R"(
2088     define void @test(i32 %x, i32 %y) {
2089       %c1 = icmp ult i32 %x, 10
2090       %c2 = icmp ult i32 %y, 15
2091       %A = or i1 %c1, %c2 ; negated
2092       ; x >= 10 /\ y >= 15
2093       %A2 = icmp ult i32 %x, 5
2094       %A3 = icmp uge i32 %y, 10
2095       %A4 = icmp ult i32 %x, 15
2096       ret void
2097     }
2098   )");
2099   const DataLayout &DL = M->getDataLayout();
2100   EXPECT_EQ(isImpliedCondition(A, A2, DL, false), false);
2101   EXPECT_EQ(isImpliedCondition(A, A3, DL, false), true);
2102   EXPECT_EQ(isImpliedCondition(A, A4, DL, false), std::nullopt);
2103 }
2104 
2105 TEST_F(ValueTrackingTest, IsImpliedConditionOr2) {
2106   parseAssembly(R"(
2107     define void @test(i32 %x, i32 %y) {
2108       %c1 = icmp ult i32 %x, 10
2109       %c2 = icmp ult i32 %y, 15
2110       %A = select i1 %c1, i1 true, i1 %c2 ; negated
2111       ; x >= 10 /\ y >= 15
2112       %A2 = icmp ult i32 %x, 5
2113       %A3 = icmp uge i32 %y, 10
2114       %A4 = icmp ult i32 %x, 15
2115       ret void
2116     }
2117   )");
2118   const DataLayout &DL = M->getDataLayout();
2119   EXPECT_EQ(isImpliedCondition(A, A2, DL, false), false);
2120   EXPECT_EQ(isImpliedCondition(A, A3, DL, false), true);
2121   EXPECT_EQ(isImpliedCondition(A, A4, DL, false), std::nullopt);
2122 }
2123 
2124 TEST_F(ComputeKnownBitsTest, KnownNonZeroShift) {
2125   // %q is known nonzero without known bits.
2126   // Because %q is nonzero, %A[0] is known to be zero.
2127   parseAssembly(
2128       "define i8 @test(i8 %p, ptr %pq) {\n"
2129       "  %q = load i8, ptr %pq, !range !0\n"
2130       "  %A = shl i8 %p, %q\n"
2131       "  ret i8 %A\n"
2132       "}\n"
2133       "!0 = !{ i8 1, i8 5 }\n");
2134   expectKnownBits(/*zero*/ 1u, /*one*/ 0u);
2135 }
2136 
2137 TEST_F(ComputeKnownBitsTest, ComputeKnownFshl) {
2138   // fshl(....1111....0000, 00..1111........, 6)
2139   // = 11....000000..11
2140   parseAssembly(
2141       "define i16 @test(i16 %a, i16 %b) {\n"
2142       "  %aa = shl i16 %a, 4\n"
2143       "  %bb = lshr i16 %b, 2\n"
2144       "  %aaa = or i16 %aa, 3840\n"
2145       "  %bbb = or i16 %bb, 3840\n"
2146       "  %A = call i16 @llvm.fshl.i16(i16 %aaa, i16 %bbb, i16 6)\n"
2147       "  ret i16 %A\n"
2148       "}\n"
2149       "declare i16 @llvm.fshl.i16(i16, i16, i16)\n");
2150   expectKnownBits(/*zero*/ 1008u, /*one*/ 49155u);
2151 }
2152 
2153 TEST_F(ComputeKnownBitsTest, ComputeKnownFshr) {
2154   // fshr(....1111....0000, 00..1111........, 26)
2155   // = 11....000000..11
2156   parseAssembly(
2157       "define i16 @test(i16 %a, i16 %b) {\n"
2158       "  %aa = shl i16 %a, 4\n"
2159       "  %bb = lshr i16 %b, 2\n"
2160       "  %aaa = or i16 %aa, 3840\n"
2161       "  %bbb = or i16 %bb, 3840\n"
2162       "  %A = call i16 @llvm.fshr.i16(i16 %aaa, i16 %bbb, i16 26)\n"
2163       "  ret i16 %A\n"
2164       "}\n"
2165       "declare i16 @llvm.fshr.i16(i16, i16, i16)\n");
2166   expectKnownBits(/*zero*/ 1008u, /*one*/ 49155u);
2167 }
2168 
2169 TEST_F(ComputeKnownBitsTest, ComputeKnownFshlZero) {
2170   // fshl(....1111....0000, 00..1111........, 0)
2171   // = ....1111....0000
2172   parseAssembly(
2173       "define i16 @test(i16 %a, i16 %b) {\n"
2174       "  %aa = shl i16 %a, 4\n"
2175       "  %bb = lshr i16 %b, 2\n"
2176       "  %aaa = or i16 %aa, 3840\n"
2177       "  %bbb = or i16 %bb, 3840\n"
2178       "  %A = call i16 @llvm.fshl.i16(i16 %aaa, i16 %bbb, i16 0)\n"
2179       "  ret i16 %A\n"
2180       "}\n"
2181       "declare i16 @llvm.fshl.i16(i16, i16, i16)\n");
2182   expectKnownBits(/*zero*/ 15u, /*one*/ 3840u);
2183 }
2184 
2185 TEST_F(ComputeKnownBitsTest, ComputeKnownUAddSatLeadingOnes) {
2186   // uadd.sat(1111...1, ........)
2187   // = 1111....
2188   parseAssembly(
2189       "define i8 @test(i8 %a, i8 %b) {\n"
2190       "  %aa = or i8 %a, 241\n"
2191       "  %A = call i8 @llvm.uadd.sat.i8(i8 %aa, i8 %b)\n"
2192       "  ret i8 %A\n"
2193       "}\n"
2194       "declare i8 @llvm.uadd.sat.i8(i8, i8)\n");
2195   expectKnownBits(/*zero*/ 0u, /*one*/ 240u);
2196 }
2197 
2198 TEST_F(ComputeKnownBitsTest, ComputeKnownUAddSatOnesPreserved) {
2199   // uadd.sat(00...011, .1...110)
2200   // = .......1
2201   parseAssembly(
2202       "define i8 @test(i8 %a, i8 %b) {\n"
2203       "  %aa = or i8 %a, 3\n"
2204       "  %aaa = and i8 %aa, 59\n"
2205       "  %bb = or i8 %b, 70\n"
2206       "  %bbb = and i8 %bb, 254\n"
2207       "  %A = call i8 @llvm.uadd.sat.i8(i8 %aaa, i8 %bbb)\n"
2208       "  ret i8 %A\n"
2209       "}\n"
2210       "declare i8 @llvm.uadd.sat.i8(i8, i8)\n");
2211   expectKnownBits(/*zero*/ 0u, /*one*/ 1u);
2212 }
2213 
2214 TEST_F(ComputeKnownBitsTest, ComputeKnownUSubSatLHSLeadingZeros) {
2215   // usub.sat(0000...0, ........)
2216   // = 0000....
2217   parseAssembly(
2218       "define i8 @test(i8 %a, i8 %b) {\n"
2219       "  %aa = and i8 %a, 14\n"
2220       "  %A = call i8 @llvm.usub.sat.i8(i8 %aa, i8 %b)\n"
2221       "  ret i8 %A\n"
2222       "}\n"
2223       "declare i8 @llvm.usub.sat.i8(i8, i8)\n");
2224   expectKnownBits(/*zero*/ 240u, /*one*/ 0u);
2225 }
2226 
2227 TEST_F(ComputeKnownBitsTest, ComputeKnownUSubSatRHSLeadingOnes) {
2228   // usub.sat(........, 1111...1)
2229   // = 0000....
2230   parseAssembly(
2231       "define i8 @test(i8 %a, i8 %b) {\n"
2232       "  %bb = or i8 %a, 241\n"
2233       "  %A = call i8 @llvm.usub.sat.i8(i8 %a, i8 %bb)\n"
2234       "  ret i8 %A\n"
2235       "}\n"
2236       "declare i8 @llvm.usub.sat.i8(i8, i8)\n");
2237   expectKnownBits(/*zero*/ 240u, /*one*/ 0u);
2238 }
2239 
2240 TEST_F(ComputeKnownBitsTest, ComputeKnownUSubSatZerosPreserved) {
2241   // usub.sat(11...011, .1...110)
2242   // = ......0.
2243   parseAssembly(
2244       "define i8 @test(i8 %a, i8 %b) {\n"
2245       "  %aa = or i8 %a, 195\n"
2246       "  %aaa = and i8 %aa, 251\n"
2247       "  %bb = or i8 %b, 70\n"
2248       "  %bbb = and i8 %bb, 254\n"
2249       "  %A = call i8 @llvm.usub.sat.i8(i8 %aaa, i8 %bbb)\n"
2250       "  ret i8 %A\n"
2251       "}\n"
2252       "declare i8 @llvm.usub.sat.i8(i8, i8)\n");
2253   expectKnownBits(/*zero*/ 2u, /*one*/ 0u);
2254 }
2255 
2256 TEST_F(ComputeKnownBitsTest, ComputeKnownBitsPtrToIntTrunc) {
2257   // ptrtoint truncates the pointer type. Make sure we don't crash.
2258   parseAssembly(
2259       "define void @test(ptr %p) {\n"
2260       "  %A = load ptr, ptr %p\n"
2261       "  %i = ptrtoint ptr %A to i32\n"
2262       "  %m = and i32 %i, 31\n"
2263       "  %c = icmp eq i32 %m, 0\n"
2264       "  call void @llvm.assume(i1 %c)\n"
2265       "  ret void\n"
2266       "}\n"
2267       "declare void @llvm.assume(i1)\n");
2268   AssumptionCache AC(*F);
2269   KnownBits Known = computeKnownBits(
2270       A, M->getDataLayout(), /* Depth */ 0, &AC, F->front().getTerminator());
2271   EXPECT_TRUE(Known.isUnknown());
2272 }
2273 
2274 TEST_F(ComputeKnownBitsTest, ComputeKnownBitsPtrToIntZext) {
2275   // ptrtoint zero extends the pointer type. Make sure we don't crash.
2276   parseAssembly(
2277       "define void @test(ptr %p) {\n"
2278       "  %A = load ptr, ptr %p\n"
2279       "  %i = ptrtoint ptr %A to i128\n"
2280       "  %m = and i128 %i, 31\n"
2281       "  %c = icmp eq i128 %m, 0\n"
2282       "  call void @llvm.assume(i1 %c)\n"
2283       "  ret void\n"
2284       "}\n"
2285       "declare void @llvm.assume(i1)\n");
2286   AssumptionCache AC(*F);
2287   KnownBits Known = computeKnownBits(
2288       A, M->getDataLayout(), /* Depth */ 0, &AC, F->front().getTerminator());
2289   EXPECT_TRUE(Known.isUnknown());
2290 }
2291 
2292 TEST_F(ComputeKnownBitsTest, ComputeKnownBitsFreeze) {
2293   parseAssembly("define void @test() {\n"
2294                 "  %m = call i32 @any_num()\n"
2295                 "  %A = freeze i32 %m\n"
2296                 "  %n = and i32 %m, 31\n"
2297                 "  %c = icmp eq i32 %n, 0\n"
2298                 "  call void @llvm.assume(i1 %c)\n"
2299                 "  ret void\n"
2300                 "}\n"
2301                 "declare void @llvm.assume(i1)\n"
2302                 "declare i32 @any_num()\n");
2303   AssumptionCache AC(*F);
2304   KnownBits Known = computeKnownBits(A, M->getDataLayout(), /* Depth */ 0, &AC,
2305                                      F->front().getTerminator());
2306   EXPECT_EQ(Known.Zero.getZExtValue(), 31u);
2307   EXPECT_EQ(Known.One.getZExtValue(), 0u);
2308 }
2309 
2310 TEST_F(ComputeKnownBitsTest, ComputeKnownBitsAddWithRange) {
2311   parseAssembly("define void @test(ptr %p) {\n"
2312                 "  %A = load i64, ptr %p, !range !{i64 64, i64 65536}\n"
2313                 "  %APlus512 = add i64 %A, 512\n"
2314                 "  %c = icmp ugt i64 %APlus512, 523\n"
2315                 "  call void @llvm.assume(i1 %c)\n"
2316                 "  ret void\n"
2317                 "}\n"
2318                 "declare void @llvm.assume(i1)\n");
2319   AssumptionCache AC(*F);
2320   KnownBits Known = computeKnownBits(A, M->getDataLayout(), /* Depth */ 0, &AC,
2321                                      F->front().getTerminator());
2322   EXPECT_EQ(Known.Zero.getZExtValue(), ~(65536llu - 1));
2323   EXPECT_EQ(Known.One.getZExtValue(), 0u);
2324   Instruction &APlus512 = findInstructionByName(F, "APlus512");
2325   Known = computeKnownBits(&APlus512, M->getDataLayout(), /* Depth */ 0, &AC,
2326                            F->front().getTerminator());
2327   // We know of one less zero because 512 may have produced a 1 that
2328   // got carried all the way to the first trailing zero.
2329   EXPECT_EQ(Known.Zero.getZExtValue(), (~(65536llu - 1)) << 1);
2330   EXPECT_EQ(Known.One.getZExtValue(), 0u);
2331   // The known range is not precise given computeKnownBits works
2332   // with the masks of zeros and ones, not the ranges.
2333   EXPECT_EQ(Known.getMinValue(), 0u);
2334   EXPECT_EQ(Known.getMaxValue(), 131071);
2335 }
2336 
2337 TEST_F(ComputeKnownBitsTest, ComputeKnownBitsUnknownVScale) {
2338   Module M("", Context);
2339   IRBuilder<> Builder(Context);
2340   Function *TheFn =
2341       Intrinsic::getDeclaration(&M, Intrinsic::vscale, {Builder.getInt32Ty()});
2342   CallInst *CI = Builder.CreateCall(TheFn, {}, {}, "");
2343 
2344   KnownBits Known = computeKnownBits(CI, M.getDataLayout(), /* Depth */ 0);
2345   // There is no parent function so we cannot look up the vscale_range
2346   // attribute to determine the number of bits.
2347   EXPECT_EQ(Known.One.getZExtValue(), 0u);
2348   EXPECT_EQ(Known.Zero.getZExtValue(), 0u);
2349 
2350   BasicBlock *BB = BasicBlock::Create(Context);
2351   CI->insertInto(BB, BB->end());
2352   Known = computeKnownBits(CI, M.getDataLayout(), /* Depth */ 0);
2353   // There is no parent function so we cannot look up the vscale_range
2354   // attribute to determine the number of bits.
2355   EXPECT_EQ(Known.One.getZExtValue(), 0u);
2356   EXPECT_EQ(Known.Zero.getZExtValue(), 0u);
2357 
2358   CI->removeFromParent();
2359   delete CI;
2360   delete BB;
2361 }
2362 
2363 // 512 + [32, 64) doesn't produce overlapping bits.
2364 // Make sure we get all the individual bits properly.
2365 TEST_F(ComputeKnownBitsTest, ComputeKnownBitsAddWithRangeNoOverlap) {
2366   parseAssembly("define void @test(ptr %p) {\n"
2367                 "  %A = load i64, ptr %p, !range !{i64 32, i64 64}\n"
2368                 "  %APlus512 = add i64 %A, 512\n"
2369                 "  %c = icmp ugt i64 %APlus512, 523\n"
2370                 "  call void @llvm.assume(i1 %c)\n"
2371                 "  ret void\n"
2372                 "}\n"
2373                 "declare void @llvm.assume(i1)\n");
2374   AssumptionCache AC(*F);
2375   KnownBits Known = computeKnownBits(A, M->getDataLayout(), /* Depth */ 0, &AC,
2376                                      F->front().getTerminator());
2377   EXPECT_EQ(Known.Zero.getZExtValue(), ~(64llu - 1));
2378   EXPECT_EQ(Known.One.getZExtValue(), 32u);
2379   Instruction &APlus512 = findInstructionByName(F, "APlus512");
2380   Known = computeKnownBits(&APlus512, M->getDataLayout(), /* Depth */ 0, &AC,
2381                            F->front().getTerminator());
2382   EXPECT_EQ(Known.Zero.getZExtValue(), ~512llu & ~(64llu - 1));
2383   EXPECT_EQ(Known.One.getZExtValue(), 512u | 32u);
2384   // The known range is not precise given computeKnownBits works
2385   // with the masks of zeros and ones, not the ranges.
2386   EXPECT_EQ(Known.getMinValue(), 544);
2387   EXPECT_EQ(Known.getMaxValue(), 575);
2388 }
2389 
2390 TEST_F(ComputeKnownBitsTest, ComputeKnownBitsGEPWithRange) {
2391   parseAssembly(
2392       "define void @test(ptr %p) {\n"
2393       "  %A = load i64, ptr %p, !range !{i64 64, i64 65536}\n"
2394       "  %APtr = inttoptr i64 %A to float*"
2395       "  %APtrPlus512 = getelementptr float, float* %APtr, i32 128\n"
2396       "  %c = icmp ugt float* %APtrPlus512, inttoptr (i32 523 to float*)\n"
2397       "  call void @llvm.assume(i1 %c)\n"
2398       "  ret void\n"
2399       "}\n"
2400       "declare void @llvm.assume(i1)\n");
2401   AssumptionCache AC(*F);
2402   KnownBits Known = computeKnownBits(A, M->getDataLayout(), /* Depth */ 0, &AC,
2403                                      F->front().getTerminator());
2404   EXPECT_EQ(Known.Zero.getZExtValue(), ~(65536llu - 1));
2405   EXPECT_EQ(Known.One.getZExtValue(), 0u);
2406   Instruction &APtrPlus512 = findInstructionByName(F, "APtrPlus512");
2407   Known = computeKnownBits(&APtrPlus512, M->getDataLayout(), /* Depth */ 0, &AC,
2408                            F->front().getTerminator());
2409   // We know of one less zero because 512 may have produced a 1 that
2410   // got carried all the way to the first trailing zero.
2411   EXPECT_EQ(Known.Zero.getZExtValue(), ~(65536llu - 1) << 1);
2412   EXPECT_EQ(Known.One.getZExtValue(), 0u);
2413   // The known range is not precise given computeKnownBits works
2414   // with the masks of zeros and ones, not the ranges.
2415   EXPECT_EQ(Known.getMinValue(), 0u);
2416   EXPECT_EQ(Known.getMaxValue(), 131071);
2417 }
2418 
2419 // 4*128 + [32, 64) doesn't produce overlapping bits.
2420 // Make sure we get all the individual bits properly.
2421 // This test is useful to check that we account for the scaling factor
2422 // in the gep. Indeed, gep float, [32,64), 128 is not 128 + [32,64).
2423 TEST_F(ComputeKnownBitsTest, ComputeKnownBitsGEPWithRangeNoOverlap) {
2424   parseAssembly(
2425       "define void @test(ptr %p) {\n"
2426       "  %A = load i64, ptr %p, !range !{i64 32, i64 64}\n"
2427       "  %APtr = inttoptr i64 %A to float*"
2428       "  %APtrPlus512 = getelementptr float, float* %APtr, i32 128\n"
2429       "  %c = icmp ugt float* %APtrPlus512, inttoptr (i32 523 to float*)\n"
2430       "  call void @llvm.assume(i1 %c)\n"
2431       "  ret void\n"
2432       "}\n"
2433       "declare void @llvm.assume(i1)\n");
2434   AssumptionCache AC(*F);
2435   KnownBits Known = computeKnownBits(A, M->getDataLayout(), /* Depth */ 0, &AC,
2436                                      F->front().getTerminator());
2437   EXPECT_EQ(Known.Zero.getZExtValue(), ~(64llu - 1));
2438   EXPECT_EQ(Known.One.getZExtValue(), 32u);
2439   Instruction &APtrPlus512 = findInstructionByName(F, "APtrPlus512");
2440   Known = computeKnownBits(&APtrPlus512, M->getDataLayout(), /* Depth */ 0, &AC,
2441                            F->front().getTerminator());
2442   EXPECT_EQ(Known.Zero.getZExtValue(), ~512llu & ~(64llu - 1));
2443   EXPECT_EQ(Known.One.getZExtValue(), 512u | 32u);
2444   // The known range is not precise given computeKnownBits works
2445   // with the masks of zeros and ones, not the ranges.
2446   EXPECT_EQ(Known.getMinValue(), 544);
2447   EXPECT_EQ(Known.getMaxValue(), 575);
2448 }
2449 
2450 TEST_F(ComputeKnownBitsTest, ComputeKnownBitsAbsoluteSymbol) {
2451   auto M = parseModule(R"(
2452     @absolute_0_255 = external global [128 x i32], align 1, !absolute_symbol !0
2453     @absolute_0_256 = external global [128 x i32], align 1, !absolute_symbol !1
2454     @absolute_256_512 = external global [128 x i32], align 1, !absolute_symbol !2
2455     @absolute_0_neg1 = external global [128 x i32], align 1, !absolute_symbol !3
2456     @absolute_neg32_32 = external global [128 x i32], align 1, !absolute_symbol !4
2457     @absolute_neg32_33 = external global [128 x i32], align 1, !absolute_symbol !5
2458     @absolute_neg64_neg32 = external global [128 x i32], align 1, !absolute_symbol !6
2459     @absolute_0_256_align8 = external global [128 x i32], align 8, !absolute_symbol !1
2460 
2461     !0 = !{i64 0, i64 255}
2462     !1 = !{i64 0, i64 256}
2463     !2 = !{i64 256, i64 512}
2464     !3 = !{i64 0, i64 -1}
2465     !4 = !{i64 -32, i64 32}
2466     !5 = !{i64 -32, i64 33}
2467     !6 = !{i64 -64, i64 -32}
2468   )");
2469 
2470   GlobalValue *Absolute_0_255 = M->getNamedValue("absolute_0_255");
2471   GlobalValue *Absolute_0_256 = M->getNamedValue("absolute_0_256");
2472   GlobalValue *Absolute_256_512 = M->getNamedValue("absolute_256_512");
2473   GlobalValue *Absolute_0_Neg1 = M->getNamedValue("absolute_0_neg1");
2474   GlobalValue *Absolute_Neg32_32 = M->getNamedValue("absolute_neg32_32");
2475   GlobalValue *Absolute_Neg32_33 = M->getNamedValue("absolute_neg32_33");
2476   GlobalValue *Absolute_Neg64_Neg32 = M->getNamedValue("absolute_neg64_neg32");
2477   GlobalValue *Absolute_0_256_Align8 =
2478       M->getNamedValue("absolute_0_256_align8");
2479 
2480   KnownBits Known_0_255 = computeKnownBits(Absolute_0_255, M->getDataLayout());
2481   EXPECT_EQ(64u - 8u, Known_0_255.countMinLeadingZeros());
2482   EXPECT_EQ(0u, Known_0_255.countMinTrailingZeros());
2483   EXPECT_EQ(0u, Known_0_255.countMinLeadingOnes());
2484   EXPECT_EQ(0u, Known_0_255.countMinTrailingOnes());
2485 
2486   KnownBits Known_0_256 = computeKnownBits(Absolute_0_256, M->getDataLayout());
2487   EXPECT_EQ(64u - 8u, Known_0_256.countMinLeadingZeros());
2488   EXPECT_EQ(0u, Known_0_256.countMinTrailingZeros());
2489   EXPECT_EQ(0u, Known_0_256.countMinLeadingOnes());
2490   EXPECT_EQ(0u, Known_0_256.countMinTrailingOnes());
2491 
2492   KnownBits Known_256_512 =
2493       computeKnownBits(Absolute_256_512, M->getDataLayout());
2494   EXPECT_EQ(64u - 8u, Known_0_255.countMinLeadingZeros());
2495   EXPECT_EQ(0u, Known_0_255.countMinTrailingZeros());
2496   EXPECT_EQ(0u, Known_0_255.countMinLeadingOnes());
2497   EXPECT_EQ(0u, Known_0_255.countMinTrailingOnes());
2498 
2499   KnownBits Known_0_Neg1 =
2500       computeKnownBits(Absolute_0_Neg1, M->getDataLayout());
2501   EXPECT_EQ(0u, Known_0_Neg1.countMinLeadingZeros());
2502   EXPECT_EQ(0u, Known_0_Neg1.countMinTrailingZeros());
2503   EXPECT_EQ(0u, Known_0_Neg1.countMinLeadingOnes());
2504   EXPECT_EQ(0u, Known_0_Neg1.countMinTrailingOnes());
2505 
2506   KnownBits Known_Neg32_32 =
2507       computeKnownBits(Absolute_Neg32_32, M->getDataLayout());
2508   EXPECT_EQ(0u, Known_Neg32_32.countMinLeadingZeros());
2509   EXPECT_EQ(0u, Known_Neg32_32.countMinTrailingZeros());
2510   EXPECT_EQ(0u, Known_Neg32_32.countMinLeadingOnes());
2511   EXPECT_EQ(0u, Known_Neg32_32.countMinTrailingOnes());
2512   EXPECT_EQ(1u, Known_Neg32_32.countMinSignBits());
2513 
2514   KnownBits Known_Neg32_33 =
2515       computeKnownBits(Absolute_Neg32_33, M->getDataLayout());
2516   EXPECT_EQ(0u, Known_Neg32_33.countMinLeadingZeros());
2517   EXPECT_EQ(0u, Known_Neg32_33.countMinTrailingZeros());
2518   EXPECT_EQ(0u, Known_Neg32_33.countMinLeadingOnes());
2519   EXPECT_EQ(0u, Known_Neg32_33.countMinTrailingOnes());
2520   EXPECT_EQ(1u, Known_Neg32_33.countMinSignBits());
2521 
2522   KnownBits Known_Neg32_Neg32 =
2523       computeKnownBits(Absolute_Neg64_Neg32, M->getDataLayout());
2524   EXPECT_EQ(0u, Known_Neg32_Neg32.countMinLeadingZeros());
2525   EXPECT_EQ(0u, Known_Neg32_Neg32.countMinTrailingZeros());
2526   EXPECT_EQ(58u, Known_Neg32_Neg32.countMinLeadingOnes());
2527   EXPECT_EQ(0u, Known_Neg32_Neg32.countMinTrailingOnes());
2528   EXPECT_EQ(58u, Known_Neg32_Neg32.countMinSignBits());
2529 
2530   KnownBits Known_0_256_Align8 =
2531       computeKnownBits(Absolute_0_256_Align8, M->getDataLayout());
2532   EXPECT_EQ(64u - 8u, Known_0_256_Align8.countMinLeadingZeros());
2533   EXPECT_EQ(3u, Known_0_256_Align8.countMinTrailingZeros());
2534   EXPECT_EQ(0u, Known_0_256_Align8.countMinLeadingOnes());
2535   EXPECT_EQ(0u, Known_0_256_Align8.countMinTrailingOnes());
2536 }
2537 
2538 TEST_F(ValueTrackingTest, HaveNoCommonBitsSet) {
2539   {
2540     // Check for an inverted mask: (X & ~M) op (Y & M).
2541     auto M = parseModule(R"(
2542   define i32 @test(i32 %X, i32 %Y, i32 %M) {
2543     %1 = xor i32 %M, -1
2544     %LHS = and i32 %1, %X
2545     %RHS = and i32 %Y, %M
2546     %Ret = add i32 %LHS, %RHS
2547     ret i32 %Ret
2548   })");
2549 
2550     auto *F = M->getFunction("test");
2551     auto *LHS = findInstructionByNameOrNull(F, "LHS");
2552     auto *RHS = findInstructionByNameOrNull(F, "RHS");
2553 
2554     const DataLayout &DL = M->getDataLayout();
2555     EXPECT_TRUE(haveNoCommonBitsSet(LHS, RHS, DL));
2556     EXPECT_TRUE(haveNoCommonBitsSet(RHS, LHS, DL));
2557   }
2558   {
2559     // Check for (A & B) and ~(A | B)
2560     auto M = parseModule(R"(
2561   define void @test(i32 %A, i32 %B) {
2562     %LHS = and i32 %A, %B
2563     %or = or i32 %A, %B
2564     %RHS = xor i32 %or, -1
2565 
2566     %LHS2 = and i32 %B, %A
2567     %or2 = or i32 %A, %B
2568     %RHS2 = xor i32 %or2, -1
2569 
2570     ret void
2571   })");
2572 
2573     auto *F = M->getFunction("test");
2574     const DataLayout &DL = M->getDataLayout();
2575 
2576     auto *LHS = findInstructionByNameOrNull(F, "LHS");
2577     auto *RHS = findInstructionByNameOrNull(F, "RHS");
2578     EXPECT_TRUE(haveNoCommonBitsSet(LHS, RHS, DL));
2579     EXPECT_TRUE(haveNoCommonBitsSet(RHS, LHS, DL));
2580 
2581     auto *LHS2 = findInstructionByNameOrNull(F, "LHS2");
2582     auto *RHS2 = findInstructionByNameOrNull(F, "RHS2");
2583     EXPECT_TRUE(haveNoCommonBitsSet(LHS2, RHS2, DL));
2584     EXPECT_TRUE(haveNoCommonBitsSet(RHS2, LHS2, DL));
2585   }
2586   {
2587     // Check for (A & B) and ~(A | B) in vector version
2588     auto M = parseModule(R"(
2589   define void @test(<2 x i32> %A, <2 x i32> %B) {
2590     %LHS = and <2 x i32> %A, %B
2591     %or = or <2 x i32> %A, %B
2592     %RHS = xor <2 x i32> %or, <i32 -1, i32 -1>
2593 
2594     %LHS2 = and <2 x i32> %B, %A
2595     %or2 = or <2 x i32> %A, %B
2596     %RHS2 = xor <2 x i32> %or2, <i32 -1, i32 -1>
2597 
2598     ret void
2599   })");
2600 
2601     auto *F = M->getFunction("test");
2602     const DataLayout &DL = M->getDataLayout();
2603 
2604     auto *LHS = findInstructionByNameOrNull(F, "LHS");
2605     auto *RHS = findInstructionByNameOrNull(F, "RHS");
2606     EXPECT_TRUE(haveNoCommonBitsSet(LHS, RHS, DL));
2607     EXPECT_TRUE(haveNoCommonBitsSet(RHS, LHS, DL));
2608 
2609     auto *LHS2 = findInstructionByNameOrNull(F, "LHS2");
2610     auto *RHS2 = findInstructionByNameOrNull(F, "RHS2");
2611     EXPECT_TRUE(haveNoCommonBitsSet(LHS2, RHS2, DL));
2612     EXPECT_TRUE(haveNoCommonBitsSet(RHS2, LHS2, DL));
2613   }
2614 }
2615 
2616 class IsBytewiseValueTest : public ValueTrackingTest,
2617                             public ::testing::WithParamInterface<
2618                                 std::pair<const char *, const char *>> {
2619 protected:
2620 };
2621 
2622 const std::pair<const char *, const char *> IsBytewiseValueTests[] = {
2623     {
2624         "i8 0",
2625         "i48* null",
2626     },
2627     {
2628         "i8 undef",
2629         "i48* undef",
2630     },
2631     {
2632         "i8 0",
2633         "i8 zeroinitializer",
2634     },
2635     {
2636         "i8 0",
2637         "i8 0",
2638     },
2639     {
2640         "i8 -86",
2641         "i8 -86",
2642     },
2643     {
2644         "i8 -1",
2645         "i8 -1",
2646     },
2647     {
2648         "i8 undef",
2649         "i16 undef",
2650     },
2651     {
2652         "i8 0",
2653         "i16 0",
2654     },
2655     {
2656         "",
2657         "i16 7",
2658     },
2659     {
2660         "i8 -86",
2661         "i16 -21846",
2662     },
2663     {
2664         "i8 -1",
2665         "i16 -1",
2666     },
2667     {
2668         "i8 0",
2669         "i48 0",
2670     },
2671     {
2672         "i8 -1",
2673         "i48 -1",
2674     },
2675     {
2676         "i8 0",
2677         "i49 0",
2678     },
2679     {
2680         "",
2681         "i49 -1",
2682     },
2683     {
2684         "i8 0",
2685         "half 0xH0000",
2686     },
2687     {
2688         "i8 -85",
2689         "half 0xHABAB",
2690     },
2691     {
2692         "i8 0",
2693         "float 0.0",
2694     },
2695     {
2696         "i8 -1",
2697         "float 0xFFFFFFFFE0000000",
2698     },
2699     {
2700         "i8 0",
2701         "double 0.0",
2702     },
2703     {
2704         "i8 -15",
2705         "double 0xF1F1F1F1F1F1F1F1",
2706     },
2707     {
2708         "i8 undef",
2709         "i16* undef",
2710     },
2711     {
2712         "i8 0",
2713         "i16* inttoptr (i64 0 to i16*)",
2714     },
2715     {
2716         "i8 -1",
2717         "i16* inttoptr (i64 -1 to i16*)",
2718     },
2719     {
2720         "i8 -86",
2721         "i16* inttoptr (i64 -6148914691236517206 to i16*)",
2722     },
2723     {
2724         "",
2725         "i16* inttoptr (i48 -1 to i16*)",
2726     },
2727     {
2728         "i8 -1",
2729         "i16* inttoptr (i96 -1 to i16*)",
2730     },
2731     {
2732         "i8 undef",
2733         "[0 x i8] zeroinitializer",
2734     },
2735     {
2736         "i8 undef",
2737         "[0 x i8] undef",
2738     },
2739     {
2740         "i8 undef",
2741         "[5 x [0 x i8]] zeroinitializer",
2742     },
2743     {
2744         "i8 undef",
2745         "[5 x [0 x i8]] undef",
2746     },
2747     {
2748         "i8 0",
2749         "[6 x i8] zeroinitializer",
2750     },
2751     {
2752         "i8 undef",
2753         "[6 x i8] undef",
2754     },
2755     {
2756         "i8 1",
2757         "[5 x i8] [i8 1, i8 1, i8 1, i8 1, i8 1]",
2758     },
2759     {
2760         "",
2761         "[5 x i64] [i64 1, i64 1, i64 1, i64 1, i64 1]",
2762     },
2763     {
2764         "i8 -1",
2765         "[5 x i64] [i64 -1, i64 -1, i64 -1, i64 -1, i64 -1]",
2766     },
2767     {
2768         "",
2769         "[4 x i8] [i8 1, i8 2, i8 1, i8 1]",
2770     },
2771     {
2772         "i8 1",
2773         "[4 x i8] [i8 1, i8 undef, i8 1, i8 1]",
2774     },
2775     {
2776         "i8 0",
2777         "<6 x i8> zeroinitializer",
2778     },
2779     {
2780         "i8 undef",
2781         "<6 x i8> undef",
2782     },
2783     {
2784         "i8 1",
2785         "<5 x i8> <i8 1, i8 1, i8 1, i8 1, i8 1>",
2786     },
2787     {
2788         "",
2789         "<5 x i64> <i64 1, i64 1, i64 1, i64 1, i64 1>",
2790     },
2791     {
2792         "i8 -1",
2793         "<5 x i64> <i64 -1, i64 -1, i64 -1, i64 -1, i64 -1>",
2794     },
2795     {
2796         "",
2797         "<4 x i8> <i8 1, i8 1, i8 2, i8 1>",
2798     },
2799     {
2800         "i8 5",
2801         "<2 x i8> < i8 5, i8 undef >",
2802     },
2803     {
2804         "i8 0",
2805         "[2 x [2 x i16]] zeroinitializer",
2806     },
2807     {
2808         "i8 undef",
2809         "[2 x [2 x i16]] undef",
2810     },
2811     {
2812         "i8 -86",
2813         "[2 x [2 x i16]] [[2 x i16] [i16 -21846, i16 -21846], "
2814         "[2 x i16] [i16 -21846, i16 -21846]]",
2815     },
2816     {
2817         "",
2818         "[2 x [2 x i16]] [[2 x i16] [i16 -21846, i16 -21846], "
2819         "[2 x i16] [i16 -21836, i16 -21846]]",
2820     },
2821     {
2822         "i8 undef",
2823         "{ } zeroinitializer",
2824     },
2825     {
2826         "i8 undef",
2827         "{ } undef",
2828     },
2829     {
2830         "i8 undef",
2831         "{ {}, {} } zeroinitializer",
2832     },
2833     {
2834         "i8 undef",
2835         "{ {}, {} } undef",
2836     },
2837     {
2838         "i8 0",
2839         "{i8, i64, i16*} zeroinitializer",
2840     },
2841     {
2842         "i8 undef",
2843         "{i8, i64, i16*} undef",
2844     },
2845     {
2846         "i8 -86",
2847         "{i8, i64, i16*} {i8 -86, i64 -6148914691236517206, i16* undef}",
2848     },
2849     {
2850         "",
2851         "{i8, i64, i16*} {i8 86, i64 -6148914691236517206, i16* undef}",
2852     },
2853 };
2854 
2855 INSTANTIATE_TEST_SUITE_P(IsBytewiseValueParamTests, IsBytewiseValueTest,
2856                          ::testing::ValuesIn(IsBytewiseValueTests));
2857 
2858 TEST_P(IsBytewiseValueTest, IsBytewiseValue) {
2859   auto M = parseModule(std::string("@test = global ") + GetParam().second);
2860   GlobalVariable *GV = dyn_cast<GlobalVariable>(M->getNamedValue("test"));
2861   Value *Actual = isBytewiseValue(GV->getInitializer(), M->getDataLayout());
2862   std::string Buff;
2863   raw_string_ostream S(Buff);
2864   if (Actual)
2865     S << *Actual;
2866   EXPECT_EQ(GetParam().first, S.str());
2867 }
2868 
2869 TEST_F(ValueTrackingTest, ComputeConstantRange) {
2870   {
2871     // Assumptions:
2872     //  * stride >= 5
2873     //  * stride < 10
2874     //
2875     // stride = [5, 10)
2876     auto M = parseModule(R"(
2877   declare void @llvm.assume(i1)
2878 
2879   define i32 @test(i32 %stride) {
2880     %gt = icmp uge i32 %stride, 5
2881     call void @llvm.assume(i1 %gt)
2882     %lt = icmp ult i32 %stride, 10
2883     call void @llvm.assume(i1 %lt)
2884     %stride.plus.one = add nsw nuw i32 %stride, 1
2885     ret i32 %stride.plus.one
2886   })");
2887     Function *F = M->getFunction("test");
2888 
2889     AssumptionCache AC(*F);
2890     Value *Stride = &*F->arg_begin();
2891     ConstantRange CR1 = computeConstantRange(Stride, false, true, &AC, nullptr);
2892     EXPECT_TRUE(CR1.isFullSet());
2893 
2894     Instruction *I = &findInstructionByName(F, "stride.plus.one");
2895     ConstantRange CR2 = computeConstantRange(Stride, false, true, &AC, I);
2896     EXPECT_EQ(5, CR2.getLower());
2897     EXPECT_EQ(10, CR2.getUpper());
2898   }
2899 
2900   {
2901     // Assumptions:
2902     //  * stride >= 5
2903     //  * stride < 200
2904     //  * stride == 99
2905     //
2906     // stride = [99, 100)
2907     auto M = parseModule(R"(
2908   declare void @llvm.assume(i1)
2909 
2910   define i32 @test(i32 %stride) {
2911     %gt = icmp uge i32 %stride, 5
2912     call void @llvm.assume(i1 %gt)
2913     %lt = icmp ult i32 %stride, 200
2914     call void @llvm.assume(i1 %lt)
2915     %eq = icmp eq i32 %stride, 99
2916     call void @llvm.assume(i1 %eq)
2917     %stride.plus.one = add nsw nuw i32 %stride, 1
2918     ret i32 %stride.plus.one
2919   })");
2920     Function *F = M->getFunction("test");
2921 
2922     AssumptionCache AC(*F);
2923     Value *Stride = &*F->arg_begin();
2924     Instruction *I = &findInstructionByName(F, "stride.plus.one");
2925     ConstantRange CR = computeConstantRange(Stride, false, true, &AC, I);
2926     EXPECT_EQ(99, *CR.getSingleElement());
2927   }
2928 
2929   {
2930     // Assumptions:
2931     //  * stride >= 5
2932     //  * stride >= 50
2933     //  * stride < 100
2934     //  * stride < 200
2935     //
2936     // stride = [50, 100)
2937     auto M = parseModule(R"(
2938   declare void @llvm.assume(i1)
2939 
2940   define i32 @test(i32 %stride, i1 %cond) {
2941     %gt = icmp uge i32 %stride, 5
2942     call void @llvm.assume(i1 %gt)
2943     %gt.2 = icmp uge i32 %stride, 50
2944     call void @llvm.assume(i1 %gt.2)
2945     br i1 %cond, label %bb1, label %bb2
2946 
2947   bb1:
2948     %lt = icmp ult i32 %stride, 200
2949     call void @llvm.assume(i1 %lt)
2950     %lt.2 = icmp ult i32 %stride, 100
2951     call void @llvm.assume(i1 %lt.2)
2952     %stride.plus.one = add nsw nuw i32 %stride, 1
2953     ret i32 %stride.plus.one
2954 
2955   bb2:
2956     ret i32 0
2957   })");
2958     Function *F = M->getFunction("test");
2959 
2960     AssumptionCache AC(*F);
2961     Value *Stride = &*F->arg_begin();
2962     Instruction *GT2 = &findInstructionByName(F, "gt.2");
2963     ConstantRange CR = computeConstantRange(Stride, false, true, &AC, GT2);
2964     EXPECT_EQ(5, CR.getLower());
2965     EXPECT_EQ(0, CR.getUpper());
2966 
2967     Instruction *I = &findInstructionByName(F, "stride.plus.one");
2968     ConstantRange CR2 = computeConstantRange(Stride, false, true, &AC, I);
2969     EXPECT_EQ(50, CR2.getLower());
2970     EXPECT_EQ(100, CR2.getUpper());
2971   }
2972 
2973   {
2974     // Assumptions:
2975     //  * stride > 5
2976     //  * stride < 5
2977     //
2978     // stride = empty range, as the assumptions contradict each other.
2979     auto M = parseModule(R"(
2980   declare void @llvm.assume(i1)
2981 
2982   define i32 @test(i32 %stride, i1 %cond) {
2983     %gt = icmp ugt i32 %stride, 5
2984     call void @llvm.assume(i1 %gt)
2985     %lt = icmp ult i32 %stride, 5
2986     call void @llvm.assume(i1 %lt)
2987     %stride.plus.one = add nsw nuw i32 %stride, 1
2988     ret i32 %stride.plus.one
2989   })");
2990     Function *F = M->getFunction("test");
2991 
2992     AssumptionCache AC(*F);
2993     Value *Stride = &*F->arg_begin();
2994 
2995     Instruction *I = &findInstructionByName(F, "stride.plus.one");
2996     ConstantRange CR = computeConstantRange(Stride, false, true, &AC, I);
2997     EXPECT_TRUE(CR.isEmptySet());
2998   }
2999 
3000   {
3001     // Assumptions:
3002     //  * x.1 >= 5
3003     //  * x.2 < x.1
3004     //
3005     // stride = [0, -1)
3006     auto M = parseModule(R"(
3007   declare void @llvm.assume(i1)
3008 
3009   define i32 @test(i32 %x.1, i32 %x.2) {
3010     %gt = icmp uge i32 %x.1, 5
3011     call void @llvm.assume(i1 %gt)
3012     %lt = icmp ult i32 %x.2, %x.1
3013     call void @llvm.assume(i1 %lt)
3014     %stride.plus.one = add nsw nuw i32 %x.1, 1
3015     ret i32 %stride.plus.one
3016   })");
3017     Function *F = M->getFunction("test");
3018 
3019     AssumptionCache AC(*F);
3020     Value *X1 = &*(F->arg_begin());
3021     Value *X2 = &*std::next(F->arg_begin());
3022 
3023     Instruction *I = &findInstructionByName(F, "stride.plus.one");
3024     ConstantRange CR1 = computeConstantRange(X1, false, true, &AC, I);
3025     ConstantRange CR2 = computeConstantRange(X2, false, true, &AC, I);
3026 
3027     EXPECT_EQ(5, CR1.getLower());
3028     EXPECT_EQ(0, CR1.getUpper());
3029 
3030     EXPECT_EQ(0, CR2.getLower());
3031     EXPECT_EQ(0xffffffff, CR2.getUpper());
3032 
3033     // Check the depth cutoff results in a conservative result (full set) by
3034     // passing Depth == MaxDepth == 6.
3035     ConstantRange CR3 = computeConstantRange(X2, false, true, &AC, I, nullptr, 6);
3036     EXPECT_TRUE(CR3.isFullSet());
3037   }
3038   {
3039     // Assumptions:
3040     //  * x.2 <= x.1
3041     auto M = parseModule(R"(
3042   declare void @llvm.assume(i1)
3043 
3044   define i32 @test(i32 %x.1, i32 %x.2) {
3045     %lt = icmp ule i32 %x.2, %x.1
3046     call void @llvm.assume(i1 %lt)
3047     %stride.plus.one = add nsw nuw i32 %x.1, 1
3048     ret i32 %stride.plus.one
3049   })");
3050     Function *F = M->getFunction("test");
3051 
3052     AssumptionCache AC(*F);
3053     Value *X2 = &*std::next(F->arg_begin());
3054 
3055     Instruction *I = &findInstructionByName(F, "stride.plus.one");
3056     ConstantRange CR1 = computeConstantRange(X2, false, true, &AC, I);
3057     // If we don't know the value of x.2, we don't know the value of x.1.
3058     EXPECT_TRUE(CR1.isFullSet());
3059   }
3060 }
3061 
3062 struct FindAllocaForValueTestParams {
3063   const char *IR;
3064   bool AnyOffsetResult;
3065   bool ZeroOffsetResult;
3066 };
3067 
3068 class FindAllocaForValueTest
3069     : public ValueTrackingTest,
3070       public ::testing::WithParamInterface<FindAllocaForValueTestParams> {
3071 protected:
3072 };
3073 
3074 const FindAllocaForValueTestParams FindAllocaForValueTests[] = {
3075     {R"(
3076       define void @test() {
3077         %a = alloca i64
3078         %r = bitcast ptr %a to ptr
3079         ret void
3080       })",
3081      true, true},
3082 
3083     {R"(
3084       define void @test() {
3085         %a = alloca i32
3086         %r = getelementptr i32, ptr %a, i32 1
3087         ret void
3088       })",
3089      true, false},
3090 
3091     {R"(
3092       define void @test() {
3093         %a = alloca i32
3094         %r = getelementptr i32, ptr %a, i32 0
3095         ret void
3096       })",
3097      true, true},
3098 
3099     {R"(
3100       define void @test(i1 %cond) {
3101       entry:
3102         %a = alloca i32
3103         br label %bb1
3104 
3105       bb1:
3106         %r = phi ptr [ %a, %entry ], [ %r, %bb1 ]
3107         br i1 %cond, label %bb1, label %exit
3108 
3109       exit:
3110         ret void
3111       })",
3112      true, true},
3113 
3114     {R"(
3115       define void @test(i1 %cond) {
3116         %a = alloca i32
3117         %r = select i1 %cond, ptr %a, ptr %a
3118         ret void
3119       })",
3120      true, true},
3121 
3122     {R"(
3123       define void @test(i1 %cond) {
3124         %a = alloca i32
3125         %b = alloca i32
3126         %r = select i1 %cond, ptr %a, ptr %b
3127         ret void
3128       })",
3129      false, false},
3130 
3131     {R"(
3132       define void @test(i1 %cond) {
3133       entry:
3134         %a = alloca i64
3135         %a32 = bitcast ptr %a to ptr
3136         br label %bb1
3137 
3138       bb1:
3139         %x = phi ptr [ %a32, %entry ], [ %x, %bb1 ]
3140         %r = getelementptr i32, ptr %x, i32 1
3141         br i1 %cond, label %bb1, label %exit
3142 
3143       exit:
3144         ret void
3145       })",
3146      true, false},
3147 
3148     {R"(
3149       define void @test(i1 %cond) {
3150       entry:
3151         %a = alloca i64
3152         %a32 = bitcast ptr %a to ptr
3153         br label %bb1
3154 
3155       bb1:
3156         %x = phi ptr [ %a32, %entry ], [ %r, %bb1 ]
3157         %r = getelementptr i32, ptr %x, i32 1
3158         br i1 %cond, label %bb1, label %exit
3159 
3160       exit:
3161         ret void
3162       })",
3163      true, false},
3164 
3165     {R"(
3166       define void @test(i1 %cond, ptr %a) {
3167       entry:
3168         %r = bitcast ptr %a to ptr
3169         ret void
3170       })",
3171      false, false},
3172 
3173     {R"(
3174       define void @test(i1 %cond) {
3175       entry:
3176         %a = alloca i32
3177         %b = alloca i32
3178         br label %bb1
3179 
3180       bb1:
3181         %r = phi ptr [ %a, %entry ], [ %b, %bb1 ]
3182         br i1 %cond, label %bb1, label %exit
3183 
3184       exit:
3185         ret void
3186       })",
3187      false, false},
3188     {R"(
3189       declare ptr @retptr(ptr returned)
3190       define void @test(i1 %cond) {
3191         %a = alloca i32
3192         %r = call ptr @retptr(ptr %a)
3193         ret void
3194       })",
3195      true, true},
3196     {R"(
3197       declare ptr @fun(ptr)
3198       define void @test(i1 %cond) {
3199         %a = alloca i32
3200         %r = call ptr @fun(ptr %a)
3201         ret void
3202       })",
3203      false, false},
3204 };
3205 
3206 TEST_P(FindAllocaForValueTest, findAllocaForValue) {
3207   auto M = parseModule(GetParam().IR);
3208   Function *F = M->getFunction("test");
3209   Instruction *I = &findInstructionByName(F, "r");
3210   const AllocaInst *AI = findAllocaForValue(I);
3211   EXPECT_EQ(!!AI, GetParam().AnyOffsetResult);
3212 }
3213 
3214 TEST_P(FindAllocaForValueTest, findAllocaForValueZeroOffset) {
3215   auto M = parseModule(GetParam().IR);
3216   Function *F = M->getFunction("test");
3217   Instruction *I = &findInstructionByName(F, "r");
3218   const AllocaInst *AI = findAllocaForValue(I, true);
3219   EXPECT_EQ(!!AI, GetParam().ZeroOffsetResult);
3220 }
3221 
3222 INSTANTIATE_TEST_SUITE_P(FindAllocaForValueTest, FindAllocaForValueTest,
3223                          ::testing::ValuesIn(FindAllocaForValueTests));
3224