xref: /llvm-project/llvm/unittests/Analysis/ValueTrackingTest.cpp (revision b39deda3e1b3617650964de8a134ca828c1a2451)
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 
75     CxtI = findInstructionByNameOrNull(F, "CxtI");
76     CxtI2 = findInstructionByNameOrNull(F, "CxtI2");
77     CxtI3 = findInstructionByNameOrNull(F, "CxtI3");
78   }
79 
80   LLVMContext Context;
81   std::unique_ptr<Module> M;
82   Function *F = nullptr;
83   Instruction *A = nullptr;
84   // Instructions (optional)
85   Instruction *A2 = nullptr, *A3 = nullptr, *A4 = nullptr;
86 
87   // Context instructions (optional)
88   Instruction *CxtI = nullptr, *CxtI2 = nullptr, *CxtI3 = nullptr;
89 };
90 
91 class MatchSelectPatternTest : public ValueTrackingTest {
92 protected:
93   void expectPattern(const SelectPatternResult &P) {
94     Value *LHS, *RHS;
95     Instruction::CastOps CastOp;
96     SelectPatternResult R = matchSelectPattern(A, LHS, RHS, &CastOp);
97     EXPECT_EQ(P.Flavor, R.Flavor);
98     EXPECT_EQ(P.NaNBehavior, R.NaNBehavior);
99     EXPECT_EQ(P.Ordered, R.Ordered);
100   }
101 };
102 
103 class ComputeKnownBitsTest : public ValueTrackingTest {
104 protected:
105   void expectKnownBits(uint64_t Zero, uint64_t One) {
106     auto Known = computeKnownBits(A, M->getDataLayout());
107     ASSERT_FALSE(Known.hasConflict());
108     EXPECT_EQ(Known.One.getZExtValue(), One);
109     EXPECT_EQ(Known.Zero.getZExtValue(), Zero);
110   }
111 };
112 
113 class ComputeKnownFPClassTest : public ValueTrackingTest {
114 protected:
115   void expectKnownFPClass(unsigned KnownTrue, std::optional<bool> SignBitKnown,
116                           Instruction *TestVal = nullptr) {
117     if (!TestVal)
118       TestVal = A;
119 
120     KnownFPClass Known = computeKnownFPClass(TestVal, M->getDataLayout());
121     EXPECT_EQ(KnownTrue, Known.KnownFPClasses);
122     EXPECT_EQ(SignBitKnown, Known.SignBit);
123   }
124 };
125 }
126 
127 TEST_F(MatchSelectPatternTest, SimpleFMin) {
128   parseAssembly(
129       "define float @test(float %a) {\n"
130       "  %1 = fcmp ult float %a, 5.0\n"
131       "  %A = select i1 %1, float %a, float 5.0\n"
132       "  ret float %A\n"
133       "}\n");
134   expectPattern({SPF_FMINNUM, SPNB_RETURNS_NAN, false});
135 }
136 
137 TEST_F(MatchSelectPatternTest, SimpleFMax) {
138   parseAssembly(
139       "define float @test(float %a) {\n"
140       "  %1 = fcmp ogt float %a, 5.0\n"
141       "  %A = select i1 %1, float %a, float 5.0\n"
142       "  ret float %A\n"
143       "}\n");
144   expectPattern({SPF_FMAXNUM, SPNB_RETURNS_OTHER, true});
145 }
146 
147 TEST_F(MatchSelectPatternTest, SwappedFMax) {
148   parseAssembly(
149       "define float @test(float %a) {\n"
150       "  %1 = fcmp olt float 5.0, %a\n"
151       "  %A = select i1 %1, float %a, float 5.0\n"
152       "  ret float %A\n"
153       "}\n");
154   expectPattern({SPF_FMAXNUM, SPNB_RETURNS_OTHER, false});
155 }
156 
157 TEST_F(MatchSelectPatternTest, SwappedFMax2) {
158   parseAssembly(
159       "define float @test(float %a) {\n"
160       "  %1 = fcmp olt float %a, 5.0\n"
161       "  %A = select i1 %1, float 5.0, float %a\n"
162       "  ret float %A\n"
163       "}\n");
164   expectPattern({SPF_FMAXNUM, SPNB_RETURNS_NAN, false});
165 }
166 
167 TEST_F(MatchSelectPatternTest, SwappedFMax3) {
168   parseAssembly(
169       "define float @test(float %a) {\n"
170       "  %1 = fcmp ult float %a, 5.0\n"
171       "  %A = select i1 %1, float 5.0, float %a\n"
172       "  ret float %A\n"
173       "}\n");
174   expectPattern({SPF_FMAXNUM, SPNB_RETURNS_OTHER, true});
175 }
176 
177 TEST_F(MatchSelectPatternTest, FastFMin) {
178   parseAssembly(
179       "define float @test(float %a) {\n"
180       "  %1 = fcmp nnan olt float %a, 5.0\n"
181       "  %A = select i1 %1, float %a, float 5.0\n"
182       "  ret float %A\n"
183       "}\n");
184   expectPattern({SPF_FMINNUM, SPNB_RETURNS_ANY, false});
185 }
186 
187 TEST_F(MatchSelectPatternTest, FMinConstantZero) {
188   parseAssembly(
189       "define float @test(float %a) {\n"
190       "  %1 = fcmp ole float %a, 0.0\n"
191       "  %A = select i1 %1, float %a, float 0.0\n"
192       "  ret float %A\n"
193       "}\n");
194   // This shouldn't be matched, as %a could be -0.0.
195   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
196 }
197 
198 TEST_F(MatchSelectPatternTest, FMinConstantZeroNsz) {
199   parseAssembly(
200       "define float @test(float %a) {\n"
201       "  %1 = fcmp nsz ole float %a, 0.0\n"
202       "  %A = select i1 %1, float %a, float 0.0\n"
203       "  ret float %A\n"
204       "}\n");
205   // But this should be, because we've ignored signed zeroes.
206   expectPattern({SPF_FMINNUM, SPNB_RETURNS_OTHER, true});
207 }
208 
209 TEST_F(MatchSelectPatternTest, FMinMismatchConstantZero1) {
210   parseAssembly(
211       "define float @test(float %a) {\n"
212       "  %1 = fcmp olt float -0.0, %a\n"
213       "  %A = select i1 %1, float 0.0, float %a\n"
214       "  ret float %A\n"
215       "}\n");
216   // The sign of zero doesn't matter in fcmp.
217   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
218 }
219 
220 TEST_F(MatchSelectPatternTest, FMinMismatchConstantZero2) {
221   parseAssembly(
222       "define float @test(float %a) {\n"
223       "  %1 = fcmp ogt float %a, -0.0\n"
224       "  %A = select i1 %1, float 0.0, float %a\n"
225       "  ret float %A\n"
226       "}\n");
227   // The sign of zero doesn't matter in fcmp.
228   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
229 }
230 
231 TEST_F(MatchSelectPatternTest, FMinMismatchConstantZero3) {
232   parseAssembly(
233       "define float @test(float %a) {\n"
234       "  %1 = fcmp olt float 0.0, %a\n"
235       "  %A = select i1 %1, float -0.0, float %a\n"
236       "  ret float %A\n"
237       "}\n");
238   // The sign of zero doesn't matter in fcmp.
239   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
240 }
241 
242 TEST_F(MatchSelectPatternTest, FMinMismatchConstantZero4) {
243   parseAssembly(
244       "define float @test(float %a) {\n"
245       "  %1 = fcmp ogt float %a, 0.0\n"
246       "  %A = select i1 %1, float -0.0, float %a\n"
247       "  ret float %A\n"
248       "}\n");
249   // The sign of zero doesn't matter in fcmp.
250   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
251 }
252 
253 TEST_F(MatchSelectPatternTest, FMinMismatchConstantZero5) {
254   parseAssembly(
255       "define float @test(float %a) {\n"
256       "  %1 = fcmp ogt float -0.0, %a\n"
257       "  %A = select i1 %1, float %a, float 0.0\n"
258       "  ret float %A\n"
259       "}\n");
260   // The sign of zero doesn't matter in fcmp.
261   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
262 }
263 
264 TEST_F(MatchSelectPatternTest, FMinMismatchConstantZero6) {
265   parseAssembly(
266       "define float @test(float %a) {\n"
267       "  %1 = fcmp olt float %a, -0.0\n"
268       "  %A = select i1 %1, float %a, float 0.0\n"
269       "  ret float %A\n"
270       "}\n");
271   // The sign of zero doesn't matter in fcmp.
272   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
273 }
274 
275 TEST_F(MatchSelectPatternTest, FMinMismatchConstantZero7) {
276   parseAssembly(
277       "define float @test(float %a) {\n"
278       "  %1 = fcmp ogt float 0.0, %a\n"
279       "  %A = select i1 %1, float %a, float -0.0\n"
280       "  ret float %A\n"
281       "}\n");
282   // The sign of zero doesn't matter in fcmp.
283   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
284 }
285 
286 TEST_F(MatchSelectPatternTest, FMinMismatchConstantZero8) {
287   parseAssembly(
288       "define float @test(float %a) {\n"
289       "  %1 = fcmp olt float %a, 0.0\n"
290       "  %A = select i1 %1, float %a, float -0.0\n"
291       "  ret float %A\n"
292       "}\n");
293   // The sign of zero doesn't matter in fcmp.
294   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
295 }
296 
297 TEST_F(MatchSelectPatternTest, FMaxMismatchConstantZero1) {
298   parseAssembly(
299       "define float @test(float %a) {\n"
300       "  %1 = fcmp ogt float -0.0, %a\n"
301       "  %A = select i1 %1, float 0.0, float %a\n"
302       "  ret float %A\n"
303       "}\n");
304   // The sign of zero doesn't matter in fcmp.
305   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
306 }
307 
308 TEST_F(MatchSelectPatternTest, FMaxMismatchConstantZero2) {
309   parseAssembly(
310       "define float @test(float %a) {\n"
311       "  %1 = fcmp olt float %a, -0.0\n"
312       "  %A = select i1 %1, float 0.0, float %a\n"
313       "  ret float %A\n"
314       "}\n");
315   // The sign of zero doesn't matter in fcmp.
316   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
317 }
318 
319 TEST_F(MatchSelectPatternTest, FMaxMismatchConstantZero3) {
320   parseAssembly(
321       "define float @test(float %a) {\n"
322       "  %1 = fcmp ogt float 0.0, %a\n"
323       "  %A = select i1 %1, float -0.0, float %a\n"
324       "  ret float %A\n"
325       "}\n");
326   // The sign of zero doesn't matter in fcmp.
327   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
328 }
329 
330 TEST_F(MatchSelectPatternTest, FMaxMismatchConstantZero4) {
331   parseAssembly(
332       "define float @test(float %a) {\n"
333       "  %1 = fcmp olt float %a, 0.0\n"
334       "  %A = select i1 %1, float -0.0, float %a\n"
335       "  ret float %A\n"
336       "}\n");
337   // The sign of zero doesn't matter in fcmp.
338   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
339 }
340 
341 TEST_F(MatchSelectPatternTest, FMaxMismatchConstantZero5) {
342   parseAssembly(
343       "define float @test(float %a) {\n"
344       "  %1 = fcmp olt float -0.0, %a\n"
345       "  %A = select i1 %1, float %a, float 0.0\n"
346       "  ret float %A\n"
347       "}\n");
348   // The sign of zero doesn't matter in fcmp.
349   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
350 }
351 
352 TEST_F(MatchSelectPatternTest, FMaxMismatchConstantZero6) {
353   parseAssembly(
354       "define float @test(float %a) {\n"
355       "  %1 = fcmp ogt float %a, -0.0\n"
356       "  %A = select i1 %1, float %a, float 0.0\n"
357       "  ret float %A\n"
358       "}\n");
359   // The sign of zero doesn't matter in fcmp.
360   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
361 }
362 
363 TEST_F(MatchSelectPatternTest, FMaxMismatchConstantZero7) {
364   parseAssembly(
365       "define float @test(float %a) {\n"
366       "  %1 = fcmp olt float 0.0, %a\n"
367       "  %A = select i1 %1, float %a, float -0.0\n"
368       "  ret float %A\n"
369       "}\n");
370   // The sign of zero doesn't matter in fcmp.
371   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
372 }
373 
374 TEST_F(MatchSelectPatternTest, FMaxMismatchConstantZero8) {
375   parseAssembly(
376       "define float @test(float %a) {\n"
377       "  %1 = fcmp ogt float %a, 0.0\n"
378       "  %A = select i1 %1, float %a, float -0.0\n"
379       "  ret float %A\n"
380       "}\n");
381   // The sign of zero doesn't matter in fcmp.
382   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
383 }
384 
385 TEST_F(MatchSelectPatternTest, FMinMismatchConstantZeroVecUndef) {
386   parseAssembly(
387       "define <2 x float> @test(<2 x float> %a) {\n"
388       "  %1 = fcmp ogt <2 x float> %a, <float -0.0, float -0.0>\n"
389       "  %A = select <2 x i1> %1, <2 x float> <float undef, float 0.0>, <2 x float> %a\n"
390       "  ret <2 x float> %A\n"
391       "}\n");
392   // An undef in a vector constant can not be back-propagated for this analysis.
393   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
394 }
395 
396 TEST_F(MatchSelectPatternTest, FMaxMismatchConstantZeroVecUndef) {
397   parseAssembly(
398       "define <2 x float> @test(<2 x float> %a) {\n"
399       "  %1 = fcmp ogt <2 x float> %a, zeroinitializer\n"
400       "  %A = select <2 x i1> %1, <2 x float> %a, <2 x float> <float -0.0, float undef>\n"
401       "  ret <2 x float> %A\n"
402       "}\n");
403   // An undef in a vector constant can not be back-propagated for this analysis.
404   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
405 }
406 
407 TEST_F(MatchSelectPatternTest, VectorFMinimum) {
408   parseAssembly(
409       "define <4 x float> @test(<4 x float> %a) {\n"
410       "  %1 = fcmp ule <4 x float> %a, \n"
411       "    <float 5.0, float 5.0, float 5.0, float 5.0>\n"
412       "  %A = select <4 x i1> %1, <4 x float> %a,\n"
413       "     <4 x float> <float 5.0, float 5.0, float 5.0, float 5.0>\n"
414       "  ret <4 x float> %A\n"
415       "}\n");
416   // Check that pattern matching works on vectors where each lane has the same
417   // unordered pattern.
418   expectPattern({SPF_FMINNUM, SPNB_RETURNS_NAN, false});
419 }
420 
421 TEST_F(MatchSelectPatternTest, VectorFMinOtherOrdered) {
422   parseAssembly(
423       "define <4 x float> @test(<4 x float> %a) {\n"
424       "  %1 = fcmp ole <4 x float> %a, \n"
425       "    <float 5.0, float 5.0, float 5.0, float 5.0>\n"
426       "  %A = select <4 x i1> %1, <4 x float> %a,\n"
427       "     <4 x float> <float 5.0, float 5.0, float 5.0, float 5.0>\n"
428       "  ret <4 x float> %A\n"
429       "}\n");
430   // Check that pattern matching works on vectors where each lane has the same
431   // ordered pattern.
432   expectPattern({SPF_FMINNUM, SPNB_RETURNS_OTHER, true});
433 }
434 
435 TEST_F(MatchSelectPatternTest, VectorNotFMinimum) {
436   parseAssembly(
437       "define <4 x float> @test(<4 x float> %a) {\n"
438       "  %1 = fcmp ule <4 x float> %a, \n"
439       "    <float 5.0, float 0x7ff8000000000000, float 5.0, float 5.0>\n"
440       "  %A = select <4 x i1> %1, <4 x float> %a,\n"
441       "     <4 x float> <float 5.0, float 0x7ff8000000000000, float 5.0, float "
442       "5.0>\n"
443       "  ret <4 x float> %A\n"
444       "}\n");
445   // The lane that contains a NaN (0x7ff80...) behaves like a
446   // non-NaN-propagating min and the other lines behave like a NaN-propagating
447   // min, so check that neither is returned.
448   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
449 }
450 
451 TEST_F(MatchSelectPatternTest, VectorNotFMinZero) {
452   parseAssembly(
453       "define <4 x float> @test(<4 x float> %a) {\n"
454       "  %1 = fcmp ule <4 x float> %a, \n"
455       "    <float 5.0, float -0.0, float 5.0, float 5.0>\n"
456       "  %A = select <4 x i1> %1, <4 x float> %a,\n"
457       "     <4 x float> <float 5.0, float 0.0, float 5.0, float 5.0>\n"
458       "  ret <4 x float> %A\n"
459       "}\n");
460   // Always selects the second lane of %a if it is positive or negative zero, so
461   // this is stricter than a min.
462   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
463 }
464 
465 TEST_F(MatchSelectPatternTest, DoubleCastU) {
466   parseAssembly(
467       "define i32 @test(i8 %a, i8 %b) {\n"
468       "  %1 = icmp ult i8 %a, %b\n"
469       "  %2 = zext i8 %a to i32\n"
470       "  %3 = zext i8 %b to i32\n"
471       "  %A = select i1 %1, i32 %2, i32 %3\n"
472       "  ret i32 %A\n"
473       "}\n");
474   // We should be able to look through the situation where we cast both operands
475   // to the select.
476   expectPattern({SPF_UMIN, SPNB_NA, false});
477 }
478 
479 TEST_F(MatchSelectPatternTest, DoubleCastS) {
480   parseAssembly(
481       "define i32 @test(i8 %a, i8 %b) {\n"
482       "  %1 = icmp slt i8 %a, %b\n"
483       "  %2 = sext i8 %a to i32\n"
484       "  %3 = sext i8 %b to i32\n"
485       "  %A = select i1 %1, i32 %2, i32 %3\n"
486       "  ret i32 %A\n"
487       "}\n");
488   // We should be able to look through the situation where we cast both operands
489   // to the select.
490   expectPattern({SPF_SMIN, SPNB_NA, false});
491 }
492 
493 TEST_F(MatchSelectPatternTest, DoubleCastBad) {
494   parseAssembly(
495       "define i32 @test(i8 %a, i8 %b) {\n"
496       "  %1 = icmp ult i8 %a, %b\n"
497       "  %2 = zext i8 %a to i32\n"
498       "  %3 = sext i8 %b to i32\n"
499       "  %A = select i1 %1, i32 %2, i32 %3\n"
500       "  ret i32 %A\n"
501       "}\n");
502   // The cast types here aren't the same, so we cannot match an UMIN.
503   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
504 }
505 
506 TEST_F(MatchSelectPatternTest, NotNotSMin) {
507   parseAssembly(
508       "define i8 @test(i8 %a, i8 %b) {\n"
509       "  %cmp = icmp sgt i8 %a, %b\n"
510       "  %an = xor i8 %a, -1\n"
511       "  %bn = xor i8 %b, -1\n"
512       "  %A = select i1 %cmp, i8 %an, i8 %bn\n"
513       "  ret i8 %A\n"
514       "}\n");
515   expectPattern({SPF_SMIN, SPNB_NA, false});
516 }
517 
518 TEST_F(MatchSelectPatternTest, NotNotSMinSwap) {
519   parseAssembly(
520       "define <2 x i8> @test(<2 x i8> %a, <2 x i8> %b) {\n"
521       "  %cmp = icmp slt <2 x i8> %a, %b\n"
522       "  %an = xor <2 x i8> %a, <i8 -1, i8-1>\n"
523       "  %bn = xor <2 x i8> %b, <i8 -1, i8-1>\n"
524       "  %A = select <2 x i1> %cmp, <2 x i8> %bn, <2 x i8> %an\n"
525       "  ret <2 x i8> %A\n"
526       "}\n");
527   expectPattern({SPF_SMIN, SPNB_NA, false});
528 }
529 
530 TEST_F(MatchSelectPatternTest, NotNotSMax) {
531   parseAssembly(
532       "define i8 @test(i8 %a, i8 %b) {\n"
533       "  %cmp = icmp slt i8 %a, %b\n"
534       "  %an = xor i8 %a, -1\n"
535       "  %bn = xor i8 %b, -1\n"
536       "  %A = select i1 %cmp, i8 %an, i8 %bn\n"
537       "  ret i8 %A\n"
538       "}\n");
539   expectPattern({SPF_SMAX, SPNB_NA, false});
540 }
541 
542 TEST_F(MatchSelectPatternTest, NotNotSMaxSwap) {
543   parseAssembly(
544       "define <2 x i8> @test(<2 x i8> %a, <2 x i8> %b) {\n"
545       "  %cmp = icmp sgt <2 x i8> %a, %b\n"
546       "  %an = xor <2 x i8> %a, <i8 -1, i8-1>\n"
547       "  %bn = xor <2 x i8> %b, <i8 -1, i8-1>\n"
548       "  %A = select <2 x i1> %cmp, <2 x i8> %bn, <2 x i8> %an\n"
549       "  ret <2 x i8> %A\n"
550       "}\n");
551   expectPattern({SPF_SMAX, SPNB_NA, false});
552 }
553 
554 TEST_F(MatchSelectPatternTest, NotNotUMin) {
555   parseAssembly(
556       "define <2 x i8> @test(<2 x i8> %a, <2 x i8> %b) {\n"
557       "  %cmp = icmp ugt <2 x i8> %a, %b\n"
558       "  %an = xor <2 x i8> %a, <i8 -1, i8-1>\n"
559       "  %bn = xor <2 x i8> %b, <i8 -1, i8-1>\n"
560       "  %A = select <2 x i1> %cmp, <2 x i8> %an, <2 x i8> %bn\n"
561       "  ret <2 x i8> %A\n"
562       "}\n");
563   expectPattern({SPF_UMIN, SPNB_NA, false});
564 }
565 
566 TEST_F(MatchSelectPatternTest, NotNotUMinSwap) {
567   parseAssembly(
568       "define i8 @test(i8 %a, i8 %b) {\n"
569       "  %cmp = icmp ult i8 %a, %b\n"
570       "  %an = xor i8 %a, -1\n"
571       "  %bn = xor i8 %b, -1\n"
572       "  %A = select i1 %cmp, i8 %bn, i8 %an\n"
573       "  ret i8 %A\n"
574       "}\n");
575   expectPattern({SPF_UMIN, SPNB_NA, false});
576 }
577 
578 TEST_F(MatchSelectPatternTest, NotNotUMax) {
579   parseAssembly(
580       "define <2 x i8> @test(<2 x i8> %a, <2 x i8> %b) {\n"
581       "  %cmp = icmp ult <2 x i8> %a, %b\n"
582       "  %an = xor <2 x i8> %a, <i8 -1, i8-1>\n"
583       "  %bn = xor <2 x i8> %b, <i8 -1, i8-1>\n"
584       "  %A = select <2 x i1> %cmp, <2 x i8> %an, <2 x i8> %bn\n"
585       "  ret <2 x i8> %A\n"
586       "}\n");
587   expectPattern({SPF_UMAX, SPNB_NA, false});
588 }
589 
590 TEST_F(MatchSelectPatternTest, NotNotUMaxSwap) {
591   parseAssembly(
592       "define i8 @test(i8 %a, i8 %b) {\n"
593       "  %cmp = icmp ugt i8 %a, %b\n"
594       "  %an = xor i8 %a, -1\n"
595       "  %bn = xor i8 %b, -1\n"
596       "  %A = select i1 %cmp, i8 %bn, i8 %an\n"
597       "  ret i8 %A\n"
598       "}\n");
599   expectPattern({SPF_UMAX, SPNB_NA, false});
600 }
601 
602 TEST_F(MatchSelectPatternTest, NotNotEq) {
603   parseAssembly(
604       "define i8 @test(i8 %a, i8 %b) {\n"
605       "  %cmp = icmp eq i8 %a, %b\n"
606       "  %an = xor i8 %a, -1\n"
607       "  %bn = xor i8 %b, -1\n"
608       "  %A = select i1 %cmp, i8 %bn, i8 %an\n"
609       "  ret i8 %A\n"
610       "}\n");
611   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
612 }
613 
614 TEST_F(MatchSelectPatternTest, NotNotNe) {
615   parseAssembly(
616       "define i8 @test(i8 %a, i8 %b) {\n"
617       "  %cmp = icmp ne i8 %a, %b\n"
618       "  %an = xor i8 %a, -1\n"
619       "  %bn = xor i8 %b, -1\n"
620       "  %A = select i1 %cmp, i8 %bn, i8 %an\n"
621       "  ret i8 %A\n"
622       "}\n");
623   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
624 }
625 
626 TEST(ValueTracking, GuaranteedToTransferExecutionToSuccessor) {
627   StringRef Assembly =
628       "declare void @nounwind_readonly(i32*) nounwind readonly "
629       "declare void @nounwind_argmemonly(i32*) nounwind argmemonly "
630       "declare void @nounwind_willreturn(i32*) nounwind willreturn "
631       "declare void @throws_but_readonly(i32*) readonly "
632       "declare void @throws_but_argmemonly(i32*) argmemonly "
633       "declare void @throws_but_willreturn(i32*) willreturn "
634       " "
635       "declare void @unknown(i32*) "
636       " "
637       "define void @f(i32* %p) { "
638       "  call void @nounwind_readonly(i32* %p) "
639       "  call void @nounwind_argmemonly(i32* %p) "
640       "  call void @nounwind_willreturn(i32* %p)"
641       "  call void @throws_but_readonly(i32* %p) "
642       "  call void @throws_but_argmemonly(i32* %p) "
643       "  call void @throws_but_willreturn(i32* %p) "
644       "  call void @unknown(i32* %p) nounwind readonly "
645       "  call void @unknown(i32* %p) nounwind argmemonly "
646       "  call void @unknown(i32* %p) nounwind willreturn "
647       "  call void @unknown(i32* %p) readonly "
648       "  call void @unknown(i32* %p) argmemonly "
649       "  call void @unknown(i32* %p) willreturn "
650       "  ret void "
651       "} ";
652 
653   LLVMContext Context;
654   SMDiagnostic Error;
655   auto M = parseAssemblyString(Assembly, Error, Context);
656   assert(M && "Bad assembly?");
657 
658   auto *F = M->getFunction("f");
659   assert(F && "Bad assembly?");
660 
661   auto &BB = F->getEntryBlock();
662   bool ExpectedAnswers[] = {
663       false, // call void @nounwind_readonly(i32* %p)
664       false, // call void @nounwind_argmemonly(i32* %p)
665       true,  // call void @nounwind_willreturn(i32* %p)
666       false, // call void @throws_but_readonly(i32* %p)
667       false, // call void @throws_but_argmemonly(i32* %p)
668       false, // call void @throws_but_willreturn(i32* %p)
669       false, // call void @unknown(i32* %p) nounwind readonly
670       false, // call void @unknown(i32* %p) nounwind argmemonly
671       true,  // call void @unknown(i32* %p) nounwind willreturn
672       false, // call void @unknown(i32* %p) readonly
673       false, // call void @unknown(i32* %p) argmemonly
674       false, // call void @unknown(i32* %p) willreturn
675       false, // ret void
676   };
677 
678   int Index = 0;
679   for (auto &I : BB) {
680     EXPECT_EQ(isGuaranteedToTransferExecutionToSuccessor(&I),
681               ExpectedAnswers[Index])
682         << "Incorrect answer at instruction " << Index << " = " << I;
683     Index++;
684   }
685 }
686 
687 TEST_F(ValueTrackingTest, ComputeNumSignBits_PR32045) {
688   parseAssembly(
689       "define i32 @test(i32 %a) {\n"
690       "  %A = ashr i32 %a, -1\n"
691       "  ret i32 %A\n"
692       "}\n");
693   EXPECT_EQ(ComputeNumSignBits(A, M->getDataLayout()), 1u);
694 }
695 
696 // No guarantees for canonical IR in this analysis, so this just bails out.
697 TEST_F(ValueTrackingTest, ComputeNumSignBits_Shuffle) {
698   parseAssembly(
699       "define <2 x i32> @test() {\n"
700       "  %A = shufflevector <2 x i32> undef, <2 x i32> undef, <2 x i32> <i32 0, i32 0>\n"
701       "  ret <2 x i32> %A\n"
702       "}\n");
703   EXPECT_EQ(ComputeNumSignBits(A, M->getDataLayout()), 1u);
704 }
705 
706 // No guarantees for canonical IR in this analysis, so a shuffle element that
707 // references an undef value means this can't return any extra information.
708 TEST_F(ValueTrackingTest, ComputeNumSignBits_Shuffle2) {
709   parseAssembly(
710       "define <2 x i32> @test(<2 x i1> %x) {\n"
711       "  %sext = sext <2 x i1> %x to <2 x i32>\n"
712       "  %A = shufflevector <2 x i32> %sext, <2 x i32> undef, <2 x i32> <i32 0, i32 2>\n"
713       "  ret <2 x i32> %A\n"
714       "}\n");
715   EXPECT_EQ(ComputeNumSignBits(A, M->getDataLayout()), 1u);
716 }
717 
718 TEST_F(ValueTrackingTest, impliesPoisonTest_Identity) {
719   parseAssembly("define void @test(i32 %x, i32 %y) {\n"
720                 "  %A = add i32 %x, %y\n"
721                 "  ret void\n"
722                 "}");
723   EXPECT_TRUE(impliesPoison(A, A));
724 }
725 
726 TEST_F(ValueTrackingTest, impliesPoisonTest_ICmp) {
727   parseAssembly("define void @test(i32 %x) {\n"
728                 "  %A2 = icmp eq i32 %x, 0\n"
729                 "  %A = icmp eq i32 %x, 1\n"
730                 "  ret void\n"
731                 "}");
732   EXPECT_TRUE(impliesPoison(A2, A));
733 }
734 
735 TEST_F(ValueTrackingTest, impliesPoisonTest_ICmpUnknown) {
736   parseAssembly("define void @test(i32 %x, i32 %y) {\n"
737                 "  %A2 = icmp eq i32 %x, %y\n"
738                 "  %A = icmp eq i32 %x, 1\n"
739                 "  ret void\n"
740                 "}");
741   EXPECT_FALSE(impliesPoison(A2, A));
742 }
743 
744 TEST_F(ValueTrackingTest, impliesPoisonTest_AddNswOkay) {
745   parseAssembly("define void @test(i32 %x) {\n"
746                 "  %A2 = add nsw i32 %x, 1\n"
747                 "  %A = add i32 %A2, 1\n"
748                 "  ret void\n"
749                 "}");
750   EXPECT_TRUE(impliesPoison(A2, A));
751 }
752 
753 TEST_F(ValueTrackingTest, impliesPoisonTest_AddNswOkay2) {
754   parseAssembly("define void @test(i32 %x) {\n"
755                 "  %A2 = add i32 %x, 1\n"
756                 "  %A = add nsw i32 %A2, 1\n"
757                 "  ret void\n"
758                 "}");
759   EXPECT_TRUE(impliesPoison(A2, A));
760 }
761 
762 TEST_F(ValueTrackingTest, impliesPoisonTest_AddNsw) {
763   parseAssembly("define void @test(i32 %x) {\n"
764                 "  %A2 = add nsw i32 %x, 1\n"
765                 "  %A = add i32 %x, 1\n"
766                 "  ret void\n"
767                 "}");
768   EXPECT_FALSE(impliesPoison(A2, A));
769 }
770 
771 TEST_F(ValueTrackingTest, impliesPoisonTest_Cmp) {
772   parseAssembly("define void @test(i32 %x, i32 %y, i1 %c) {\n"
773                 "  %A2 = icmp eq i32 %x, %y\n"
774                 "  %A0 = icmp ult i32 %x, %y\n"
775                 "  %A = or i1 %A0, %c\n"
776                 "  ret void\n"
777                 "}");
778   EXPECT_TRUE(impliesPoison(A2, A));
779 }
780 
781 TEST_F(ValueTrackingTest, impliesPoisonTest_FCmpFMF) {
782   parseAssembly("define void @test(float %x, float %y, i1 %c) {\n"
783                 "  %A2 = fcmp nnan oeq float %x, %y\n"
784                 "  %A0 = fcmp olt float %x, %y\n"
785                 "  %A = or i1 %A0, %c\n"
786                 "  ret void\n"
787                 "}");
788   EXPECT_FALSE(impliesPoison(A2, A));
789 }
790 
791 TEST_F(ValueTrackingTest, impliesPoisonTest_AddSubSameOps) {
792   parseAssembly("define void @test(i32 %x, i32 %y, i1 %c) {\n"
793                 "  %A2 = add i32 %x, %y\n"
794                 "  %A = sub i32 %x, %y\n"
795                 "  ret void\n"
796                 "}");
797   EXPECT_TRUE(impliesPoison(A2, A));
798 }
799 
800 TEST_F(ValueTrackingTest, impliesPoisonTest_MaskCmp) {
801   parseAssembly("define void @test(i32 %x, i32 %y, i1 %c) {\n"
802                 "  %M2 = and i32 %x, 7\n"
803                 "  %A2 = icmp eq i32 %M2, 1\n"
804                 "  %M = and i32 %x, 15\n"
805                 "  %A = icmp eq i32 %M, 3\n"
806                 "  ret void\n"
807                 "}");
808   EXPECT_TRUE(impliesPoison(A2, A));
809 }
810 
811 TEST_F(ValueTrackingTest, ComputeNumSignBits_Shuffle_Pointers) {
812   parseAssembly(
813       "define <2 x i32*> @test(<2 x i32*> %x) {\n"
814       "  %A = shufflevector <2 x i32*> zeroinitializer, <2 x i32*> undef, <2 x i32> zeroinitializer\n"
815       "  ret <2 x i32*> %A\n"
816       "}\n");
817   EXPECT_EQ(ComputeNumSignBits(A, M->getDataLayout()), 64u);
818 }
819 
820 TEST(ValueTracking, propagatesPoison) {
821   std::string AsmHead =
822       "declare i32 @g(i32)\n"
823       "declare {i32, i1} @llvm.sadd.with.overflow.i32(i32 %a, i32 %b)\n"
824       "declare {i32, i1} @llvm.ssub.with.overflow.i32(i32 %a, i32 %b)\n"
825       "declare {i32, i1} @llvm.smul.with.overflow.i32(i32 %a, i32 %b)\n"
826       "declare {i32, i1} @llvm.uadd.with.overflow.i32(i32 %a, i32 %b)\n"
827       "declare {i32, i1} @llvm.usub.with.overflow.i32(i32 %a, i32 %b)\n"
828       "declare {i32, i1} @llvm.umul.with.overflow.i32(i32 %a, i32 %b)\n"
829       "declare float @llvm.sqrt.f32(float)\n"
830       "declare float @llvm.powi.f32.i32(float, i32)\n"
831       "declare float @llvm.sin.f32(float)\n"
832       "declare float @llvm.cos.f32(float)\n"
833       "declare float @llvm.pow.f32(float, float)\n"
834       "declare float @llvm.exp.f32(float)\n"
835       "declare float @llvm.exp2.f32(float)\n"
836       "declare float @llvm.log.f32(float)\n"
837       "declare float @llvm.log10.f32(float)\n"
838       "declare float @llvm.log2.f32(float)\n"
839       "declare float @llvm.fma.f32(float, float, float)\n"
840       "declare float @llvm.fabs.f32(float)\n"
841       "declare float @llvm.minnum.f32(float, float)\n"
842       "declare float @llvm.maxnum.f32(float, float)\n"
843       "declare float @llvm.minimum.f32(float, float)\n"
844       "declare float @llvm.maximum.f32(float, float)\n"
845       "declare float @llvm.copysign.f32(float, float)\n"
846       "declare float @llvm.floor.f32(float)\n"
847       "declare float @llvm.ceil.f32(float)\n"
848       "declare float @llvm.trunc.f32(float)\n"
849       "declare float @llvm.rint.f32(float)\n"
850       "declare float @llvm.nearbyint.f32(float)\n"
851       "declare float @llvm.round.f32(float)\n"
852       "declare float @llvm.roundeven.f32(float)\n"
853       "declare i32 @llvm.lround.f32(float)\n"
854       "declare i64 @llvm.llround.f32(float)\n"
855       "declare i32 @llvm.lrint.f32(float)\n"
856       "declare i64 @llvm.llrint.f32(float)\n"
857       "declare float @llvm.fmuladd.f32(float, float, float)\n"
858       "define void @f(i32 %x, i32 %y, float %fx, float %fy, "
859       "i1 %cond, i8* %p) {\n";
860   std::string AsmTail = "  ret void\n}";
861   // (propagates poison?, IR instruction)
862   SmallVector<std::tuple<bool, std::string, unsigned>, 32> Data = {
863       {true, "add i32 %x, %y", 0},
864       {true, "add i32 %x, %y", 1},
865       {true, "add nsw nuw i32 %x, %y", 0},
866       {true, "add nsw nuw i32 %x, %y", 1},
867       {true, "ashr i32 %x, %y", 0},
868       {true, "ashr i32 %x, %y", 1},
869       {true, "lshr exact i32 %x, 31", 0},
870       {true, "lshr exact i32 %x, 31", 1},
871       {true, "fadd float %fx, %fy", 0},
872       {true, "fadd float %fx, %fy", 1},
873       {true, "fsub float %fx, %fy", 0},
874       {true, "fsub float %fx, %fy", 1},
875       {true, "fmul float %fx, %fy", 0},
876       {true, "fmul float %fx, %fy", 1},
877       {true, "fdiv float %fx, %fy", 0},
878       {true, "fdiv float %fx, %fy", 1},
879       {true, "frem float %fx, %fy", 0},
880       {true, "frem float %fx, %fy", 1},
881       {true, "fneg float %fx", 0},
882       {true, "fcmp oeq float %fx, %fy", 0},
883       {true, "fcmp oeq float %fx, %fy", 1},
884       {true, "icmp eq i32 %x, %y", 0},
885       {true, "icmp eq i32 %x, %y", 1},
886       {true, "getelementptr i8, i8* %p, i32 %x", 0},
887       {true, "getelementptr i8, i8* %p, i32 %x", 1},
888       {true, "getelementptr inbounds i8, i8* %p, i32 %x", 0},
889       {true, "getelementptr inbounds i8, i8* %p, i32 %x", 1},
890       {true, "bitcast float %fx to i32", 0},
891       {true, "select i1 %cond, i32 %x, i32 %y", 0},
892       {false, "select i1 %cond, i32 %x, i32 %y", 1},
893       {false, "select i1 %cond, i32 %x, i32 %y", 2},
894       {false, "freeze i32 %x", 0},
895       {true, "udiv i32 %x, %y", 0},
896       {true, "udiv i32 %x, %y", 1},
897       {true, "urem i32 %x, %y", 0},
898       {true, "urem i32 %x, %y", 1},
899       {true, "sdiv exact i32 %x, %y", 0},
900       {true, "sdiv exact i32 %x, %y", 1},
901       {true, "srem i32 %x, %y", 0},
902       {true, "srem i32 %x, %y", 1},
903       {false, "call i32 @g(i32 %x)", 0},
904       {false, "call i32 @g(i32 %x)", 1},
905       {true, "call {i32, i1} @llvm.sadd.with.overflow.i32(i32 %x, i32 %y)", 0},
906       {true, "call {i32, i1} @llvm.ssub.with.overflow.i32(i32 %x, i32 %y)", 0},
907       {true, "call {i32, i1} @llvm.smul.with.overflow.i32(i32 %x, i32 %y)", 0},
908       {true, "call {i32, i1} @llvm.uadd.with.overflow.i32(i32 %x, i32 %y)", 0},
909       {true, "call {i32, i1} @llvm.usub.with.overflow.i32(i32 %x, i32 %y)", 0},
910       {true, "call {i32, i1} @llvm.umul.with.overflow.i32(i32 %x, i32 %y)", 0},
911       {false, "call float @llvm.sqrt.f32(float %fx)", 0},
912       {false, "call float @llvm.powi.f32.i32(float %fx, i32 %x)", 0},
913       {false, "call float @llvm.sin.f32(float %fx)", 0},
914       {false, "call float @llvm.cos.f32(float %fx)", 0},
915       {false, "call float @llvm.pow.f32(float %fx, float %fy)", 0},
916       {false, "call float @llvm.exp.f32(float %fx)", 0},
917       {false, "call float @llvm.exp2.f32(float %fx)", 0},
918       {false, "call float @llvm.log.f32(float %fx)", 0},
919       {false, "call float @llvm.log10.f32(float %fx)", 0},
920       {false, "call float @llvm.log2.f32(float %fx)", 0},
921       {false, "call float @llvm.fma.f32(float %fx, float %fx, float %fy)", 0},
922       {false, "call float @llvm.fabs.f32(float %fx)", 0},
923       {false, "call float @llvm.minnum.f32(float %fx, float %fy)", 0},
924       {false, "call float @llvm.maxnum.f32(float %fx, float %fy)", 0},
925       {false, "call float @llvm.minimum.f32(float %fx, float %fy)", 0},
926       {false, "call float @llvm.maximum.f32(float %fx, float %fy)", 0},
927       {false, "call float @llvm.copysign.f32(float %fx, float %fy)", 0},
928       {false, "call float @llvm.floor.f32(float %fx)", 0},
929       {false, "call float @llvm.ceil.f32(float %fx)", 0},
930       {false, "call float @llvm.trunc.f32(float %fx)", 0},
931       {false, "call float @llvm.rint.f32(float %fx)", 0},
932       {false, "call float @llvm.nearbyint.f32(float %fx)", 0},
933       {false, "call float @llvm.round.f32(float %fx)", 0},
934       {false, "call float @llvm.roundeven.f32(float %fx)", 0},
935       {false, "call i32 @llvm.lround.f32(float %fx)", 0},
936       {false, "call i64 @llvm.llround.f32(float %fx)", 0},
937       {false, "call i32 @llvm.lrint.f32(float %fx)", 0},
938       {false, "call i64 @llvm.llrint.f32(float %fx)", 0},
939       {false, "call float @llvm.fmuladd.f32(float %fx, float %fx, float %fy)",
940        0}};
941 
942   std::string AssemblyStr = AsmHead;
943   for (auto &Itm : Data)
944     AssemblyStr += std::get<1>(Itm) + "\n";
945   AssemblyStr += AsmTail;
946 
947   LLVMContext Context;
948   SMDiagnostic Error;
949   auto M = parseAssemblyString(AssemblyStr, Error, Context);
950   assert(M && "Bad assembly?");
951 
952   auto *F = M->getFunction("f");
953   assert(F && "Bad assembly?");
954 
955   auto &BB = F->getEntryBlock();
956 
957   int Index = 0;
958   for (auto &I : BB) {
959     if (isa<ReturnInst>(&I))
960       break;
961     bool ExpectedVal = std::get<0>(Data[Index]);
962     unsigned OpIdx = std::get<2>(Data[Index]);
963     EXPECT_EQ(propagatesPoison(I.getOperandUse(OpIdx)), ExpectedVal)
964         << "Incorrect answer at instruction " << Index << " = " << I;
965     Index++;
966   }
967 }
968 
969 TEST_F(ValueTrackingTest, programUndefinedIfPoison) {
970   parseAssembly("declare i32 @any_num()"
971                 "define void @test(i32 %mask) {\n"
972                 "  %A = call i32 @any_num()\n"
973                 "  %B = or i32 %A, %mask\n"
974                 "  udiv i32 1, %B"
975                 "  ret void\n"
976                 "}\n");
977   // If %A was poison, udiv raises UB regardless of %mask's value
978   EXPECT_EQ(programUndefinedIfPoison(A), true);
979 }
980 
981 TEST_F(ValueTrackingTest, programUndefinedIfUndefOrPoison) {
982   parseAssembly("declare i32 @any_num()"
983                 "define void @test(i32 %mask) {\n"
984                 "  %A = call i32 @any_num()\n"
985                 "  %B = or i32 %A, %mask\n"
986                 "  udiv i32 1, %B"
987                 "  ret void\n"
988                 "}\n");
989   // If %A was undef and %mask was 1, udiv does not raise UB
990   EXPECT_EQ(programUndefinedIfUndefOrPoison(A), false);
991 }
992 
993 TEST_F(ValueTrackingTest, isGuaranteedNotToBePoison_exploitBranchCond) {
994   parseAssembly("declare i1 @any_bool()"
995                 "define void @test(i1 %y) {\n"
996                 "  %A = call i1 @any_bool()\n"
997                 "  %cond = and i1 %A, %y\n"
998                 "  br i1 %cond, label %BB1, label %BB2\n"
999                 "BB1:\n"
1000                 "  ret void\n"
1001                 "BB2:\n"
1002                 "  ret void\n"
1003                 "}\n");
1004   DominatorTree DT(*F);
1005   for (auto &BB : *F) {
1006     if (&BB == &F->getEntryBlock())
1007       continue;
1008 
1009     EXPECT_EQ(isGuaranteedNotToBePoison(A, nullptr, BB.getTerminator(), &DT),
1010               true)
1011         << "isGuaranteedNotToBePoison does not hold at " << *BB.getTerminator();
1012   }
1013 }
1014 
1015 TEST_F(ValueTrackingTest, isGuaranteedNotToBePoison_phi) {
1016   parseAssembly("declare i32 @any_i32(i32)"
1017                 "define void @test() {\n"
1018                 "ENTRY:\n"
1019                 "  br label %LOOP\n"
1020                 "LOOP:\n"
1021                 "  %A = phi i32 [0, %ENTRY], [%A.next, %NEXT]\n"
1022                 "  %A.next = call i32 @any_i32(i32 %A)\n"
1023                 "  %cond = icmp eq i32 %A.next, 0\n"
1024                 "  br i1 %cond, label %NEXT, label %EXIT\n"
1025                 "NEXT:\n"
1026                 "  br label %LOOP\n"
1027                 "EXIT:\n"
1028                 "  ret void\n"
1029                 "}\n");
1030   DominatorTree DT(*F);
1031   for (auto &BB : *F) {
1032     if (BB.getName() == "LOOP") {
1033       EXPECT_EQ(isGuaranteedNotToBePoison(A, nullptr, A, &DT), true)
1034           << "isGuaranteedNotToBePoison does not hold";
1035     }
1036   }
1037 }
1038 
1039 TEST_F(ValueTrackingTest, isGuaranteedNotToBeUndefOrPoison) {
1040   parseAssembly("declare void @f(i32 noundef)"
1041                 "define void @test(i32 %x) {\n"
1042                 "  %A = bitcast i32 %x to i32\n"
1043                 "  call void @f(i32 noundef %x)\n"
1044                 "  ret void\n"
1045                 "}\n");
1046   EXPECT_EQ(isGuaranteedNotToBeUndefOrPoison(A), true);
1047   EXPECT_EQ(isGuaranteedNotToBeUndefOrPoison(UndefValue::get(IntegerType::get(Context, 8))), false);
1048   EXPECT_EQ(isGuaranteedNotToBeUndefOrPoison(PoisonValue::get(IntegerType::get(Context, 8))), false);
1049   EXPECT_EQ(isGuaranteedNotToBePoison(UndefValue::get(IntegerType::get(Context, 8))), true);
1050   EXPECT_EQ(isGuaranteedNotToBePoison(PoisonValue::get(IntegerType::get(Context, 8))), false);
1051 
1052   Type *Int32Ty = Type::getInt32Ty(Context);
1053   Constant *CU = UndefValue::get(Int32Ty);
1054   Constant *CP = PoisonValue::get(Int32Ty);
1055   Constant *C1 = ConstantInt::get(Int32Ty, 1);
1056   Constant *C2 = ConstantInt::get(Int32Ty, 2);
1057 
1058   {
1059     Constant *V1 = ConstantVector::get({C1, C2});
1060     EXPECT_TRUE(isGuaranteedNotToBeUndefOrPoison(V1));
1061     EXPECT_TRUE(isGuaranteedNotToBePoison(V1));
1062   }
1063 
1064   {
1065     Constant *V2 = ConstantVector::get({C1, CU});
1066     EXPECT_FALSE(isGuaranteedNotToBeUndefOrPoison(V2));
1067     EXPECT_TRUE(isGuaranteedNotToBePoison(V2));
1068   }
1069 
1070   {
1071     Constant *V3 = ConstantVector::get({C1, CP});
1072     EXPECT_FALSE(isGuaranteedNotToBeUndefOrPoison(V3));
1073     EXPECT_FALSE(isGuaranteedNotToBePoison(V3));
1074   }
1075 }
1076 
1077 TEST_F(ValueTrackingTest, isGuaranteedNotToBeUndefOrPoison_assume) {
1078   parseAssembly("declare i1 @f_i1()\n"
1079                 "declare i32 @f_i32()\n"
1080                 "declare void @llvm.assume(i1)\n"
1081                 "define void @test() {\n"
1082                 "  %A = call i32 @f_i32()\n"
1083                 "  %cond = call i1 @f_i1()\n"
1084                 "  %CxtI = add i32 0, 0\n"
1085                 "  br i1 %cond, label %BB1, label %EXIT\n"
1086                 "BB1:\n"
1087                 "  %CxtI2 = add i32 0, 0\n"
1088                 "  %cond2 = call i1 @f_i1()\n"
1089                 "  call void @llvm.assume(i1 true) [ \"noundef\"(i32 %A) ]\n"
1090                 "  br i1 %cond2, label %BB2, label %EXIT\n"
1091                 "BB2:\n"
1092                 "  %CxtI3 = add i32 0, 0\n"
1093                 "  ret void\n"
1094                 "EXIT:\n"
1095                 "  ret void\n"
1096                 "}");
1097   AssumptionCache AC(*F);
1098   DominatorTree DT(*F);
1099   EXPECT_FALSE(isGuaranteedNotToBeUndefOrPoison(A, &AC, CxtI, &DT));
1100   EXPECT_FALSE(isGuaranteedNotToBeUndefOrPoison(A, &AC, CxtI2, &DT));
1101   EXPECT_TRUE(isGuaranteedNotToBeUndefOrPoison(A, &AC, CxtI3, &DT));
1102 }
1103 
1104 TEST(ValueTracking, canCreatePoisonOrUndef) {
1105   std::string AsmHead =
1106       "@s = external dso_local global i32, align 1\n"
1107       "declare i32 @g(i32)\n"
1108       "declare {i32, i1} @llvm.sadd.with.overflow.i32(i32 %a, i32 %b)\n"
1109       "declare {i32, i1} @llvm.ssub.with.overflow.i32(i32 %a, i32 %b)\n"
1110       "declare {i32, i1} @llvm.smul.with.overflow.i32(i32 %a, i32 %b)\n"
1111       "declare {i32, i1} @llvm.uadd.with.overflow.i32(i32 %a, i32 %b)\n"
1112       "declare {i32, i1} @llvm.usub.with.overflow.i32(i32 %a, i32 %b)\n"
1113       "declare {i32, i1} @llvm.umul.with.overflow.i32(i32 %a, i32 %b)\n"
1114       "define void @f(i32 %x, i32 %y, float %fx, float %fy, i1 %cond, "
1115       "<4 x i32> %vx, <4 x i32> %vx2, <vscale x 4 x i32> %svx, i8* %p) {\n";
1116   std::string AsmTail = "  ret void\n}";
1117   // (can create poison?, can create undef?, IR instruction)
1118   SmallVector<std::pair<std::pair<bool, bool>, std::string>, 32> Data = {
1119       {{false, false}, "add i32 %x, %y"},
1120       {{true, false}, "add nsw nuw i32 %x, %y"},
1121       {{true, false}, "shl i32 %x, %y"},
1122       {{true, false}, "shl <4 x i32> %vx, %vx2"},
1123       {{true, false}, "shl nsw i32 %x, %y"},
1124       {{true, false}, "shl nsw <4 x i32> %vx, <i32 0, i32 1, i32 2, i32 3>"},
1125       {{false, false}, "shl i32 %x, 31"},
1126       {{true, false}, "shl i32 %x, 32"},
1127       {{false, false}, "shl <4 x i32> %vx, <i32 0, i32 1, i32 2, i32 3>"},
1128       {{true, false}, "shl <4 x i32> %vx, <i32 0, i32 1, i32 2, i32 32>"},
1129       {{true, false}, "ashr i32 %x, %y"},
1130       {{true, false}, "ashr exact i32 %x, %y"},
1131       {{false, false}, "ashr i32 %x, 31"},
1132       {{true, false}, "ashr exact i32 %x, 31"},
1133       {{false, false}, "ashr <4 x i32> %vx, <i32 0, i32 1, i32 2, i32 3>"},
1134       {{true, false}, "ashr <4 x i32> %vx, <i32 0, i32 1, i32 2, i32 32>"},
1135       {{true, false}, "ashr exact <4 x i32> %vx, <i32 0, i32 1, i32 2, i32 3>"},
1136       {{true, false}, "lshr i32 %x, %y"},
1137       {{true, false}, "lshr exact i32 %x, 31"},
1138       {{false, false}, "udiv i32 %x, %y"},
1139       {{true, false}, "udiv exact i32 %x, %y"},
1140       {{false, false}, "getelementptr i8, i8* %p, i32 %x"},
1141       {{true, false}, "getelementptr inbounds i8, i8* %p, i32 %x"},
1142       {{true, false}, "fneg nnan float %fx"},
1143       {{false, false}, "fneg float %fx"},
1144       {{false, false}, "fadd float %fx, %fy"},
1145       {{true, false}, "fadd nnan float %fx, %fy"},
1146       {{false, false}, "urem i32 %x, %y"},
1147       {{true, false}, "fptoui float %fx to i32"},
1148       {{true, false}, "fptosi float %fx to i32"},
1149       {{false, false}, "bitcast float %fx to i32"},
1150       {{false, false}, "select i1 %cond, i32 %x, i32 %y"},
1151       {{true, false}, "select nnan i1 %cond, float %fx, float %fy"},
1152       {{true, false}, "extractelement <4 x i32> %vx, i32 %x"},
1153       {{false, false}, "extractelement <4 x i32> %vx, i32 3"},
1154       {{true, false}, "extractelement <vscale x 4 x i32> %svx, i32 4"},
1155       {{true, false}, "insertelement <4 x i32> %vx, i32 %x, i32 %y"},
1156       {{false, false}, "insertelement <4 x i32> %vx, i32 %x, i32 3"},
1157       {{true, false}, "insertelement <vscale x 4 x i32> %svx, i32 %x, i32 4"},
1158       {{false, false}, "freeze i32 %x"},
1159       {{false, false},
1160        "shufflevector <4 x i32> %vx, <4 x i32> %vx2, "
1161        "<4 x i32> <i32 0, i32 1, i32 2, i32 3>"},
1162       {{false, true},
1163        "shufflevector <4 x i32> %vx, <4 x i32> %vx2, "
1164        "<4 x i32> <i32 0, i32 1, i32 2, i32 undef>"},
1165       {{false, true},
1166        "shufflevector <vscale x 4 x i32> %svx, "
1167        "<vscale x 4 x i32> %svx, <vscale x 4 x i32> undef"},
1168       {{true, false}, "call i32 @g(i32 %x)"},
1169       {{false, false}, "call noundef i32 @g(i32 %x)"},
1170       {{true, false}, "fcmp nnan oeq float %fx, %fy"},
1171       {{false, false}, "fcmp oeq float %fx, %fy"},
1172       {{true, false}, "ashr i32 %x, ptrtoint (i32* @s to i32)"},
1173       {{false, false},
1174        "call {i32, i1} @llvm.sadd.with.overflow.i32(i32 %x, i32 %y)"},
1175       {{false, false},
1176        "call {i32, i1} @llvm.ssub.with.overflow.i32(i32 %x, i32 %y)"},
1177       {{false, false},
1178        "call {i32, i1} @llvm.smul.with.overflow.i32(i32 %x, i32 %y)"},
1179       {{false, false},
1180        "call {i32, i1} @llvm.uadd.with.overflow.i32(i32 %x, i32 %y)"},
1181       {{false, false},
1182        "call {i32, i1} @llvm.usub.with.overflow.i32(i32 %x, i32 %y)"},
1183       {{false, false},
1184        "call {i32, i1} @llvm.umul.with.overflow.i32(i32 %x, i32 %y)"}};
1185 
1186   std::string AssemblyStr = AsmHead;
1187   for (auto &Itm : Data)
1188     AssemblyStr += Itm.second + "\n";
1189   AssemblyStr += AsmTail;
1190 
1191   LLVMContext Context;
1192   SMDiagnostic Error;
1193   auto M = parseAssemblyString(AssemblyStr, Error, Context);
1194   assert(M && "Bad assembly?");
1195 
1196   auto *F = M->getFunction("f");
1197   assert(F && "Bad assembly?");
1198 
1199   auto &BB = F->getEntryBlock();
1200 
1201   int Index = 0;
1202   for (auto &I : BB) {
1203     if (isa<ReturnInst>(&I))
1204       break;
1205     bool Poison = Data[Index].first.first;
1206     bool Undef = Data[Index].first.second;
1207     EXPECT_EQ(canCreatePoison(cast<Operator>(&I)), Poison)
1208         << "Incorrect answer of canCreatePoison at instruction " << Index
1209         << " = " << I;
1210     EXPECT_EQ(canCreateUndefOrPoison(cast<Operator>(&I)), Undef || Poison)
1211         << "Incorrect answer of canCreateUndef at instruction " << Index
1212         << " = " << I;
1213     Index++;
1214   }
1215 }
1216 
1217 TEST_F(ValueTrackingTest, computePtrAlignment) {
1218   parseAssembly("declare i1 @f_i1()\n"
1219                 "declare i8* @f_i8p()\n"
1220                 "declare void @llvm.assume(i1)\n"
1221                 "define void @test() {\n"
1222                 "  %A = call i8* @f_i8p()\n"
1223                 "  %cond = call i1 @f_i1()\n"
1224                 "  %CxtI = add i32 0, 0\n"
1225                 "  br i1 %cond, label %BB1, label %EXIT\n"
1226                 "BB1:\n"
1227                 "  %CxtI2 = add i32 0, 0\n"
1228                 "  %cond2 = call i1 @f_i1()\n"
1229                 "  call void @llvm.assume(i1 true) [ \"align\"(i8* %A, i64 16) ]\n"
1230                 "  br i1 %cond2, label %BB2, label %EXIT\n"
1231                 "BB2:\n"
1232                 "  %CxtI3 = add i32 0, 0\n"
1233                 "  ret void\n"
1234                 "EXIT:\n"
1235                 "  ret void\n"
1236                 "}");
1237   AssumptionCache AC(*F);
1238   DominatorTree DT(*F);
1239   const DataLayout &DL = M->getDataLayout();
1240   EXPECT_EQ(getKnownAlignment(A, DL, CxtI, &AC, &DT), Align(1));
1241   EXPECT_EQ(getKnownAlignment(A, DL, CxtI2, &AC, &DT), Align(1));
1242   EXPECT_EQ(getKnownAlignment(A, DL, CxtI3, &AC, &DT), Align(16));
1243 }
1244 
1245 TEST_F(ComputeKnownBitsTest, ComputeKnownBits) {
1246   parseAssembly(
1247       "define i32 @test(i32 %a, i32 %b) {\n"
1248       "  %ash = mul i32 %a, 8\n"
1249       "  %aad = add i32 %ash, 7\n"
1250       "  %aan = and i32 %aad, 4095\n"
1251       "  %bsh = shl i32 %b, 4\n"
1252       "  %bad = or i32 %bsh, 6\n"
1253       "  %ban = and i32 %bad, 4095\n"
1254       "  %A = mul i32 %aan, %ban\n"
1255       "  ret i32 %A\n"
1256       "}\n");
1257   expectKnownBits(/*zero*/ 4278190085u, /*one*/ 10u);
1258 }
1259 
1260 TEST_F(ComputeKnownBitsTest, ComputeKnownMulBits) {
1261   parseAssembly(
1262       "define i32 @test(i32 %a, i32 %b) {\n"
1263       "  %aa = shl i32 %a, 5\n"
1264       "  %bb = shl i32 %b, 5\n"
1265       "  %aaa = or i32 %aa, 24\n"
1266       "  %bbb = or i32 %bb, 28\n"
1267       "  %A = mul i32 %aaa, %bbb\n"
1268       "  ret i32 %A\n"
1269       "}\n");
1270   expectKnownBits(/*zero*/ 95u, /*one*/ 32u);
1271 }
1272 
1273 TEST_F(ComputeKnownFPClassTest, SelectPos0) {
1274   parseAssembly(
1275       "define float @test(i1 %cond) {\n"
1276       "  %A = select i1 %cond, float 0.0, float 0.0"
1277       "  ret float %A\n"
1278       "}\n");
1279   expectKnownFPClass(fcPosZero, false);
1280 }
1281 
1282 TEST_F(ComputeKnownFPClassTest, SelectNeg0) {
1283   parseAssembly(
1284       "define float @test(i1 %cond) {\n"
1285       "  %A = select i1 %cond, float -0.0, float -0.0"
1286       "  ret float %A\n"
1287       "}\n");
1288   expectKnownFPClass(fcNegZero, true);
1289 }
1290 
1291 TEST_F(ComputeKnownFPClassTest, SelectPosOrNeg0) {
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(fcZero, std::nullopt);
1298 }
1299 
1300 TEST_F(ComputeKnownFPClassTest, SelectPosInf) {
1301   parseAssembly(
1302       "define float @test(i1 %cond) {\n"
1303       "  %A = select i1 %cond, float 0x7FF0000000000000, float 0x7FF0000000000000"
1304       "  ret float %A\n"
1305       "}\n");
1306   expectKnownFPClass(fcPosInf, false);
1307 }
1308 
1309 TEST_F(ComputeKnownFPClassTest, SelectNegInf) {
1310   parseAssembly(
1311       "define float @test(i1 %cond) {\n"
1312       "  %A = select i1 %cond, float 0xFFF0000000000000, float 0xFFF0000000000000"
1313       "  ret float %A\n"
1314       "}\n");
1315   expectKnownFPClass(fcNegInf, true);
1316 }
1317 
1318 TEST_F(ComputeKnownFPClassTest, SelectPosOrNegInf) {
1319   parseAssembly(
1320       "define float @test(i1 %cond) {\n"
1321       "  %A = select i1 %cond, float 0x7FF0000000000000, float 0xFFF0000000000000"
1322       "  ret float %A\n"
1323       "}\n");
1324   expectKnownFPClass(fcInf, std::nullopt);
1325 }
1326 
1327 TEST_F(ComputeKnownFPClassTest, SelectNNaN) {
1328   parseAssembly(
1329       "define float @test(i1 %cond, float %arg0, float %arg1) {\n"
1330       "  %A = select nnan i1 %cond, float %arg0, float %arg1"
1331       "  ret float %A\n"
1332       "}\n");
1333   expectKnownFPClass(~fcNan, std::nullopt);
1334 }
1335 
1336 TEST_F(ComputeKnownFPClassTest, SelectNInf) {
1337   parseAssembly(
1338       "define float @test(i1 %cond, float %arg0, float %arg1) {\n"
1339       "  %A = select ninf i1 %cond, float %arg0, float %arg1"
1340       "  ret float %A\n"
1341       "}\n");
1342   expectKnownFPClass(~fcInf, std::nullopt);
1343 }
1344 
1345 TEST_F(ComputeKnownFPClassTest, SelectNNaNNInf) {
1346   parseAssembly(
1347       "define float @test(i1 %cond, float %arg0, float %arg1) {\n"
1348       "  %A = select nnan ninf i1 %cond, float %arg0, float %arg1"
1349       "  ret float %A\n"
1350       "}\n");
1351   expectKnownFPClass(~(fcNan | fcInf), std::nullopt);
1352 }
1353 
1354 TEST_F(ComputeKnownFPClassTest, SelectNoFPClassArgUnionAll) {
1355   parseAssembly(
1356       "define float @test(i1 %cond, float nofpclass(snan ninf nsub pzero pnorm) %arg0, float nofpclass(qnan nnorm nzero psub pinf) %arg1) {\n"
1357       "  %A = select i1 %cond, float %arg0, float %arg1"
1358       "  ret float %A\n"
1359       "}\n");
1360   expectKnownFPClass(fcAllFlags, std::nullopt);
1361 }
1362 
1363 TEST_F(ComputeKnownFPClassTest, SelectNoFPClassArgNoNan) {
1364   parseAssembly(
1365       "define float @test(i1 %cond, float nofpclass(nan) %arg0, float nofpclass(nan) %arg1) {\n"
1366       "  %A = select i1 %cond, float %arg0, float %arg1"
1367       "  ret float %A\n"
1368       "}\n");
1369   expectKnownFPClass(~fcNan, std::nullopt);
1370 }
1371 
1372 TEST_F(ComputeKnownFPClassTest, SelectNoFPClassArgNoPInf) {
1373   parseAssembly(
1374       "define float @test(i1 %cond, float nofpclass(inf) %arg0, float nofpclass(pinf) %arg1) {\n"
1375       "  %A = select i1 %cond, float %arg0, float %arg1"
1376       "  ret float %A\n"
1377       "}\n");
1378   expectKnownFPClass(~fcPosInf, std::nullopt);
1379 }
1380 
1381 TEST_F(ComputeKnownFPClassTest, SelectNoFPClassArgNoNInf) {
1382   parseAssembly(
1383       "define float @test(i1 %cond, float nofpclass(ninf) %arg0, float nofpclass(inf) %arg1) {\n"
1384       "  %A = select i1 %cond, float %arg0, float %arg1"
1385       "  ret float %A\n"
1386       "}\n");
1387   expectKnownFPClass(~fcNegInf, std::nullopt);
1388 }
1389 
1390 TEST_F(ComputeKnownFPClassTest, SelectNoFPClassCallSiteNoNan) {
1391   parseAssembly(
1392       "declare float @func()\n"
1393       "define float @test() {\n"
1394       "  %A = call nofpclass(nan) float @func()\n"
1395       "  ret float %A\n"
1396       "}\n");
1397   expectKnownFPClass(~fcNan, std::nullopt);
1398 }
1399 
1400 TEST_F(ComputeKnownFPClassTest, SelectNoFPClassCallSiteNoZeros) {
1401   parseAssembly(
1402       "declare float @func()\n"
1403       "define float @test() {\n"
1404       "  %A = call nofpclass(zero) float @func()\n"
1405       "  ret float %A\n"
1406       "}\n");
1407   expectKnownFPClass(~fcZero, std::nullopt);
1408 }
1409 
1410 TEST_F(ComputeKnownFPClassTest, SelectNoFPClassDeclarationNoNan) {
1411   parseAssembly(
1412       "declare nofpclass(nan) float @no_nans()\n"
1413       "define float @test() {\n"
1414       "  %A = call float @no_nans()\n"
1415       "  ret float %A\n"
1416       "}\n");
1417   expectKnownFPClass(~fcNan, std::nullopt);
1418 }
1419 
1420 // Check nofpclass + ninf works on a callsite
1421 TEST_F(ComputeKnownFPClassTest, SelectNoFPClassCallSiteNoZerosNInfFlags) {
1422   parseAssembly(
1423       "declare float @func()\n"
1424       "define float @test() {\n"
1425       "  %A = call ninf nofpclass(zero) float @func()\n"
1426       "  ret float %A\n"
1427       "}\n");
1428   expectKnownFPClass(~(fcZero | fcInf), std::nullopt);
1429 }
1430 
1431 TEST_F(ComputeKnownFPClassTest, FNegNInf) {
1432   parseAssembly(
1433       "define float @test(float %arg) {\n"
1434       "  %A = fneg ninf float %arg"
1435       "  ret float %A\n"
1436       "}\n");
1437   expectKnownFPClass(~fcInf, std::nullopt);
1438 }
1439 
1440 TEST_F(ComputeKnownFPClassTest, FabsUnknown) {
1441   parseAssembly(
1442       "declare float @llvm.fabs.f32(float)"
1443       "define float @test(float %arg) {\n"
1444       "  %A = call float @llvm.fabs.f32(float %arg)"
1445       "  ret float %A\n"
1446       "}\n");
1447   expectKnownFPClass(fcAllFlags, false);
1448 }
1449 
1450 TEST_F(ComputeKnownFPClassTest, FNegFabsUnknown) {
1451   parseAssembly(
1452       "declare float @llvm.fabs.f32(float)"
1453       "define float @test(float %arg) {\n"
1454       "  %fabs = call float @llvm.fabs.f32(float %arg)"
1455       "  %A = fneg float %fabs"
1456       "  ret float %A\n"
1457       "}\n");
1458   expectKnownFPClass(fcAllFlags, true);
1459 }
1460 
1461 TEST_F(ComputeKnownFPClassTest, NegFabsNInf) {
1462   parseAssembly(
1463       "declare float @llvm.fabs.f32(float)"
1464       "define float @test(float %arg) {\n"
1465       "  %fabs = call ninf float @llvm.fabs.f32(float %arg)"
1466       "  %A = fneg float %fabs"
1467       "  ret float %A\n"
1468       "}\n");
1469   expectKnownFPClass(~fcInf, true);
1470 }
1471 
1472 TEST_F(ComputeKnownFPClassTest, FNegFabsNNaN) {
1473   parseAssembly(
1474       "declare float @llvm.fabs.f32(float)"
1475       "define float @test(float %arg) {\n"
1476       "  %fabs = call nnan float @llvm.fabs.f32(float %arg)"
1477       "  %A = fneg float %fabs"
1478       "  ret float %A\n"
1479       "}\n");
1480   expectKnownFPClass(~fcNan, true);
1481 }
1482 
1483 TEST_F(ComputeKnownFPClassTest, CopySignNNanSrc0) {
1484   parseAssembly(
1485       "declare float @llvm.fabs.f32(float)\n"
1486       "declare float @llvm.copysign.f32(float, float)\n"
1487       "define float @test(float %arg0, float %arg1) {\n"
1488       "  %fabs = call nnan float @llvm.fabs.f32(float %arg0)"
1489       "  %A = call float @llvm.copysign.f32(float %fabs, float %arg1)"
1490       "  ret float %A\n"
1491       "}\n");
1492   expectKnownFPClass(~fcNan, std::nullopt);
1493 }
1494 
1495 TEST_F(ComputeKnownFPClassTest, CopySignNInfSrc0_NegSign) {
1496   parseAssembly(
1497       "declare float @llvm.sqrt.f32(float)\n"
1498       "declare float @llvm.copysign.f32(float, float)\n"
1499       "define float @test(float %arg0, float %arg1) {\n"
1500       "  %ninf = call ninf float @llvm.sqrt.f32(float %arg0)"
1501       "  %A = call float @llvm.copysign.f32(float %ninf, float -1.0)"
1502       "  ret float %A\n"
1503       "}\n");
1504   expectKnownFPClass(fcNegFinite, true);
1505 }
1506 
1507 TEST_F(ComputeKnownFPClassTest, CopySignNInfSrc0_PosSign) {
1508   parseAssembly(
1509       "declare float @llvm.sqrt.f32(float)\n"
1510       "declare float @llvm.copysign.f32(float, float)\n"
1511       "define float @test(float %arg0, float %arg1) {\n"
1512       "  %ninf = call ninf float @llvm.sqrt.f32(float %arg0)"
1513       "  %A = call float @llvm.copysign.f32(float %ninf, float 1.0)"
1514       "  ret float %A\n"
1515       "}\n");
1516   expectKnownFPClass(fcPosFinite, false);
1517 }
1518 
1519 TEST_F(ComputeKnownFPClassTest, UIToFP) {
1520   parseAssembly(
1521       "define float @test(i32 %arg0, i16 %arg1) {\n"
1522       "  %A = uitofp i32 %arg0 to float"
1523       "  %A2 = uitofp i16 %arg1 to half"
1524       "  ret float %A\n"
1525       "}\n");
1526   expectKnownFPClass(fcPosFinite, false, A);
1527   expectKnownFPClass(fcPositive, false, A2);
1528 }
1529 
1530 TEST_F(ComputeKnownFPClassTest, SIToFP) {
1531   parseAssembly(
1532       "define float @test(i32 %arg0, i16 %arg1, i17 %arg2) {\n"
1533       "  %A = sitofp i32 %arg0 to float"
1534       "  %A2 = sitofp i16 %arg1 to half"
1535       "  %A3 = sitofp i17 %arg2 to half"
1536       "  ret float %A\n"
1537       "}\n");
1538   expectKnownFPClass(fcFinite, std::nullopt, A);
1539   expectKnownFPClass(fcFinite, std::nullopt, A2);
1540   expectKnownFPClass(~fcNan, std::nullopt, A3);
1541 }
1542 
1543 TEST_F(ValueTrackingTest, isNonZeroRecurrence) {
1544   parseAssembly(R"(
1545     define i1 @test(i8 %n, i8 %r) {
1546     entry:
1547       br label %loop
1548     loop:
1549       %p = phi i8 [ -1, %entry ], [ %next, %loop ]
1550       %next = add nsw i8 %p, -1
1551       %cmp1 = icmp eq i8 %p, %n
1552       br i1 %cmp1, label %exit, label %loop
1553     exit:
1554       %A = or i8 %p, %r
1555       %CxtI = icmp eq i8 %A, 0
1556       ret i1 %CxtI
1557     }
1558   )");
1559   const DataLayout &DL = M->getDataLayout();
1560   AssumptionCache AC(*F);
1561   EXPECT_TRUE(isKnownNonZero(A, DL, 0, &AC, CxtI));
1562 }
1563 
1564 TEST_F(ValueTrackingTest, KnownNonZeroFromDomCond) {
1565   parseAssembly(R"(
1566     declare i8* @f_i8()
1567     define void @test(i1 %c) {
1568       %A = call i8* @f_i8()
1569       %B = call i8* @f_i8()
1570       %c1 = icmp ne i8* %A, null
1571       %cond = and i1 %c1, %c
1572       br i1 %cond, label %T, label %Q
1573     T:
1574       %CxtI = add i32 0, 0
1575       ret void
1576     Q:
1577       %CxtI2 = add i32 0, 0
1578       ret void
1579     }
1580   )");
1581   AssumptionCache AC(*F);
1582   DominatorTree DT(*F);
1583   const DataLayout &DL = M->getDataLayout();
1584   EXPECT_EQ(isKnownNonZero(A, DL, 0, &AC, CxtI, &DT), true);
1585   EXPECT_EQ(isKnownNonZero(A, DL, 0, &AC, CxtI2, &DT), false);
1586 }
1587 
1588 TEST_F(ValueTrackingTest, KnownNonZeroFromDomCond2) {
1589   parseAssembly(R"(
1590     declare i8* @f_i8()
1591     define void @test(i1 %c) {
1592       %A = call i8* @f_i8()
1593       %B = call i8* @f_i8()
1594       %c1 = icmp ne i8* %A, null
1595       %cond = select i1 %c, i1 %c1, i1 false
1596       br i1 %cond, label %T, label %Q
1597     T:
1598       %CxtI = add i32 0, 0
1599       ret void
1600     Q:
1601       %CxtI2 = add i32 0, 0
1602       ret void
1603     }
1604   )");
1605   AssumptionCache AC(*F);
1606   DominatorTree DT(*F);
1607   const DataLayout &DL = M->getDataLayout();
1608   EXPECT_EQ(isKnownNonZero(A, DL, 0, &AC, CxtI, &DT), true);
1609   EXPECT_EQ(isKnownNonZero(A, DL, 0, &AC, CxtI2, &DT), false);
1610 }
1611 
1612 TEST_F(ValueTrackingTest, IsImpliedConditionAnd) {
1613   parseAssembly(R"(
1614     define void @test(i32 %x, i32 %y) {
1615       %c1 = icmp ult i32 %x, 10
1616       %c2 = icmp ult i32 %y, 15
1617       %A = and i1 %c1, %c2
1618       ; x < 10 /\ y < 15
1619       %A2 = icmp ult i32 %x, 20
1620       %A3 = icmp uge i32 %y, 20
1621       %A4 = icmp ult i32 %x, 5
1622       ret void
1623     }
1624   )");
1625   const DataLayout &DL = M->getDataLayout();
1626   EXPECT_EQ(isImpliedCondition(A, A2, DL), true);
1627   EXPECT_EQ(isImpliedCondition(A, A3, DL), false);
1628   EXPECT_EQ(isImpliedCondition(A, A4, DL), std::nullopt);
1629 }
1630 
1631 TEST_F(ValueTrackingTest, IsImpliedConditionAnd2) {
1632   parseAssembly(R"(
1633     define void @test(i32 %x, i32 %y) {
1634       %c1 = icmp ult i32 %x, 10
1635       %c2 = icmp ult i32 %y, 15
1636       %A = select i1 %c1, i1 %c2, i1 false
1637       ; x < 10 /\ y < 15
1638       %A2 = icmp ult i32 %x, 20
1639       %A3 = icmp uge i32 %y, 20
1640       %A4 = icmp ult i32 %x, 5
1641       ret void
1642     }
1643   )");
1644   const DataLayout &DL = M->getDataLayout();
1645   EXPECT_EQ(isImpliedCondition(A, A2, DL), true);
1646   EXPECT_EQ(isImpliedCondition(A, A3, DL), false);
1647   EXPECT_EQ(isImpliedCondition(A, A4, DL), std::nullopt);
1648 }
1649 
1650 TEST_F(ValueTrackingTest, IsImpliedConditionAndVec) {
1651   parseAssembly(R"(
1652     define void @test(<2 x i8> %x, <2 x i8> %y) {
1653       %A = icmp ult <2 x i8> %x, %y
1654       %A2 = icmp ule <2 x i8> %x, %y
1655       ret void
1656     }
1657   )");
1658   const DataLayout &DL = M->getDataLayout();
1659   EXPECT_EQ(isImpliedCondition(A, A2, DL), true);
1660 }
1661 
1662 TEST_F(ValueTrackingTest, IsImpliedConditionOr) {
1663   parseAssembly(R"(
1664     define void @test(i32 %x, i32 %y) {
1665       %c1 = icmp ult i32 %x, 10
1666       %c2 = icmp ult i32 %y, 15
1667       %A = or i1 %c1, %c2 ; negated
1668       ; x >= 10 /\ y >= 15
1669       %A2 = icmp ult i32 %x, 5
1670       %A3 = icmp uge i32 %y, 10
1671       %A4 = icmp ult i32 %x, 15
1672       ret void
1673     }
1674   )");
1675   const DataLayout &DL = M->getDataLayout();
1676   EXPECT_EQ(isImpliedCondition(A, A2, DL, false), false);
1677   EXPECT_EQ(isImpliedCondition(A, A3, DL, false), true);
1678   EXPECT_EQ(isImpliedCondition(A, A4, DL, false), std::nullopt);
1679 }
1680 
1681 TEST_F(ValueTrackingTest, IsImpliedConditionOr2) {
1682   parseAssembly(R"(
1683     define void @test(i32 %x, i32 %y) {
1684       %c1 = icmp ult i32 %x, 10
1685       %c2 = icmp ult i32 %y, 15
1686       %A = select i1 %c1, i1 true, i1 %c2 ; negated
1687       ; x >= 10 /\ y >= 15
1688       %A2 = icmp ult i32 %x, 5
1689       %A3 = icmp uge i32 %y, 10
1690       %A4 = icmp ult i32 %x, 15
1691       ret void
1692     }
1693   )");
1694   const DataLayout &DL = M->getDataLayout();
1695   EXPECT_EQ(isImpliedCondition(A, A2, DL, false), false);
1696   EXPECT_EQ(isImpliedCondition(A, A3, DL, false), true);
1697   EXPECT_EQ(isImpliedCondition(A, A4, DL, false), std::nullopt);
1698 }
1699 
1700 TEST_F(ComputeKnownBitsTest, KnownNonZeroShift) {
1701   // %q is known nonzero without known bits.
1702   // Because %q is nonzero, %A[0] is known to be zero.
1703   parseAssembly(
1704       "define i8 @test(i8 %p, i8* %pq) {\n"
1705       "  %q = load i8, i8* %pq, !range !0\n"
1706       "  %A = shl i8 %p, %q\n"
1707       "  ret i8 %A\n"
1708       "}\n"
1709       "!0 = !{ i8 1, i8 5 }\n");
1710   expectKnownBits(/*zero*/ 1u, /*one*/ 0u);
1711 }
1712 
1713 TEST_F(ComputeKnownBitsTest, ComputeKnownFshl) {
1714   // fshl(....1111....0000, 00..1111........, 6)
1715   // = 11....000000..11
1716   parseAssembly(
1717       "define i16 @test(i16 %a, i16 %b) {\n"
1718       "  %aa = shl i16 %a, 4\n"
1719       "  %bb = lshr i16 %b, 2\n"
1720       "  %aaa = or i16 %aa, 3840\n"
1721       "  %bbb = or i16 %bb, 3840\n"
1722       "  %A = call i16 @llvm.fshl.i16(i16 %aaa, i16 %bbb, i16 6)\n"
1723       "  ret i16 %A\n"
1724       "}\n"
1725       "declare i16 @llvm.fshl.i16(i16, i16, i16)\n");
1726   expectKnownBits(/*zero*/ 1008u, /*one*/ 49155u);
1727 }
1728 
1729 TEST_F(ComputeKnownBitsTest, ComputeKnownFshr) {
1730   // fshr(....1111....0000, 00..1111........, 26)
1731   // = 11....000000..11
1732   parseAssembly(
1733       "define i16 @test(i16 %a, i16 %b) {\n"
1734       "  %aa = shl i16 %a, 4\n"
1735       "  %bb = lshr i16 %b, 2\n"
1736       "  %aaa = or i16 %aa, 3840\n"
1737       "  %bbb = or i16 %bb, 3840\n"
1738       "  %A = call i16 @llvm.fshr.i16(i16 %aaa, i16 %bbb, i16 26)\n"
1739       "  ret i16 %A\n"
1740       "}\n"
1741       "declare i16 @llvm.fshr.i16(i16, i16, i16)\n");
1742   expectKnownBits(/*zero*/ 1008u, /*one*/ 49155u);
1743 }
1744 
1745 TEST_F(ComputeKnownBitsTest, ComputeKnownFshlZero) {
1746   // fshl(....1111....0000, 00..1111........, 0)
1747   // = ....1111....0000
1748   parseAssembly(
1749       "define i16 @test(i16 %a, i16 %b) {\n"
1750       "  %aa = shl i16 %a, 4\n"
1751       "  %bb = lshr i16 %b, 2\n"
1752       "  %aaa = or i16 %aa, 3840\n"
1753       "  %bbb = or i16 %bb, 3840\n"
1754       "  %A = call i16 @llvm.fshl.i16(i16 %aaa, i16 %bbb, i16 0)\n"
1755       "  ret i16 %A\n"
1756       "}\n"
1757       "declare i16 @llvm.fshl.i16(i16, i16, i16)\n");
1758   expectKnownBits(/*zero*/ 15u, /*one*/ 3840u);
1759 }
1760 
1761 TEST_F(ComputeKnownBitsTest, ComputeKnownUAddSatLeadingOnes) {
1762   // uadd.sat(1111...1, ........)
1763   // = 1111....
1764   parseAssembly(
1765       "define i8 @test(i8 %a, i8 %b) {\n"
1766       "  %aa = or i8 %a, 241\n"
1767       "  %A = call i8 @llvm.uadd.sat.i8(i8 %aa, i8 %b)\n"
1768       "  ret i8 %A\n"
1769       "}\n"
1770       "declare i8 @llvm.uadd.sat.i8(i8, i8)\n");
1771   expectKnownBits(/*zero*/ 0u, /*one*/ 240u);
1772 }
1773 
1774 TEST_F(ComputeKnownBitsTest, ComputeKnownUAddSatOnesPreserved) {
1775   // uadd.sat(00...011, .1...110)
1776   // = .......1
1777   parseAssembly(
1778       "define i8 @test(i8 %a, i8 %b) {\n"
1779       "  %aa = or i8 %a, 3\n"
1780       "  %aaa = and i8 %aa, 59\n"
1781       "  %bb = or i8 %b, 70\n"
1782       "  %bbb = and i8 %bb, 254\n"
1783       "  %A = call i8 @llvm.uadd.sat.i8(i8 %aaa, i8 %bbb)\n"
1784       "  ret i8 %A\n"
1785       "}\n"
1786       "declare i8 @llvm.uadd.sat.i8(i8, i8)\n");
1787   expectKnownBits(/*zero*/ 0u, /*one*/ 1u);
1788 }
1789 
1790 TEST_F(ComputeKnownBitsTest, ComputeKnownUSubSatLHSLeadingZeros) {
1791   // usub.sat(0000...0, ........)
1792   // = 0000....
1793   parseAssembly(
1794       "define i8 @test(i8 %a, i8 %b) {\n"
1795       "  %aa = and i8 %a, 14\n"
1796       "  %A = call i8 @llvm.usub.sat.i8(i8 %aa, i8 %b)\n"
1797       "  ret i8 %A\n"
1798       "}\n"
1799       "declare i8 @llvm.usub.sat.i8(i8, i8)\n");
1800   expectKnownBits(/*zero*/ 240u, /*one*/ 0u);
1801 }
1802 
1803 TEST_F(ComputeKnownBitsTest, ComputeKnownUSubSatRHSLeadingOnes) {
1804   // usub.sat(........, 1111...1)
1805   // = 0000....
1806   parseAssembly(
1807       "define i8 @test(i8 %a, i8 %b) {\n"
1808       "  %bb = or i8 %a, 241\n"
1809       "  %A = call i8 @llvm.usub.sat.i8(i8 %a, i8 %bb)\n"
1810       "  ret i8 %A\n"
1811       "}\n"
1812       "declare i8 @llvm.usub.sat.i8(i8, i8)\n");
1813   expectKnownBits(/*zero*/ 240u, /*one*/ 0u);
1814 }
1815 
1816 TEST_F(ComputeKnownBitsTest, ComputeKnownUSubSatZerosPreserved) {
1817   // usub.sat(11...011, .1...110)
1818   // = ......0.
1819   parseAssembly(
1820       "define i8 @test(i8 %a, i8 %b) {\n"
1821       "  %aa = or i8 %a, 195\n"
1822       "  %aaa = and i8 %aa, 251\n"
1823       "  %bb = or i8 %b, 70\n"
1824       "  %bbb = and i8 %bb, 254\n"
1825       "  %A = call i8 @llvm.usub.sat.i8(i8 %aaa, i8 %bbb)\n"
1826       "  ret i8 %A\n"
1827       "}\n"
1828       "declare i8 @llvm.usub.sat.i8(i8, i8)\n");
1829   expectKnownBits(/*zero*/ 2u, /*one*/ 0u);
1830 }
1831 
1832 TEST_F(ComputeKnownBitsTest, ComputeKnownBitsPtrToIntTrunc) {
1833   // ptrtoint truncates the pointer type.
1834   parseAssembly(
1835       "define void @test(i8** %p) {\n"
1836       "  %A = load i8*, i8** %p\n"
1837       "  %i = ptrtoint i8* %A to i32\n"
1838       "  %m = and i32 %i, 31\n"
1839       "  %c = icmp eq i32 %m, 0\n"
1840       "  call void @llvm.assume(i1 %c)\n"
1841       "  ret void\n"
1842       "}\n"
1843       "declare void @llvm.assume(i1)\n");
1844   AssumptionCache AC(*F);
1845   KnownBits Known = computeKnownBits(
1846       A, M->getDataLayout(), /* Depth */ 0, &AC, F->front().getTerminator());
1847   EXPECT_EQ(Known.Zero.getZExtValue(), 31u);
1848   EXPECT_EQ(Known.One.getZExtValue(), 0u);
1849 }
1850 
1851 TEST_F(ComputeKnownBitsTest, ComputeKnownBitsPtrToIntZext) {
1852   // ptrtoint zero extends the pointer type.
1853   parseAssembly(
1854       "define void @test(i8** %p) {\n"
1855       "  %A = load i8*, i8** %p\n"
1856       "  %i = ptrtoint i8* %A to i128\n"
1857       "  %m = and i128 %i, 31\n"
1858       "  %c = icmp eq i128 %m, 0\n"
1859       "  call void @llvm.assume(i1 %c)\n"
1860       "  ret void\n"
1861       "}\n"
1862       "declare void @llvm.assume(i1)\n");
1863   AssumptionCache AC(*F);
1864   KnownBits Known = computeKnownBits(
1865       A, M->getDataLayout(), /* Depth */ 0, &AC, F->front().getTerminator());
1866   EXPECT_EQ(Known.Zero.getZExtValue(), 31u);
1867   EXPECT_EQ(Known.One.getZExtValue(), 0u);
1868 }
1869 
1870 TEST_F(ComputeKnownBitsTest, ComputeKnownBitsFreeze) {
1871   parseAssembly("define void @test() {\n"
1872                 "  %m = call i32 @any_num()\n"
1873                 "  %A = freeze i32 %m\n"
1874                 "  %n = and i32 %m, 31\n"
1875                 "  %c = icmp eq i32 %n, 0\n"
1876                 "  call void @llvm.assume(i1 %c)\n"
1877                 "  ret void\n"
1878                 "}\n"
1879                 "declare void @llvm.assume(i1)\n"
1880                 "declare i32 @any_num()\n");
1881   AssumptionCache AC(*F);
1882   KnownBits Known = computeKnownBits(A, M->getDataLayout(), /* Depth */ 0, &AC,
1883                                      F->front().getTerminator());
1884   EXPECT_EQ(Known.Zero.getZExtValue(), 31u);
1885   EXPECT_EQ(Known.One.getZExtValue(), 0u);
1886 }
1887 
1888 TEST_F(ComputeKnownBitsTest, ComputeKnownBitsAddWithRange) {
1889   parseAssembly("define void @test(i64* %p) {\n"
1890                 "  %A = load i64, i64* %p, !range !{i64 64, i64 65536}\n"
1891                 "  %APlus512 = add i64 %A, 512\n"
1892                 "  %c = icmp ugt i64 %APlus512, 523\n"
1893                 "  call void @llvm.assume(i1 %c)\n"
1894                 "  ret void\n"
1895                 "}\n"
1896                 "declare void @llvm.assume(i1)\n");
1897   AssumptionCache AC(*F);
1898   KnownBits Known = computeKnownBits(A, M->getDataLayout(), /* Depth */ 0, &AC,
1899                                      F->front().getTerminator());
1900   EXPECT_EQ(Known.Zero.getZExtValue(), ~(65536llu - 1));
1901   EXPECT_EQ(Known.One.getZExtValue(), 0u);
1902   Instruction &APlus512 = findInstructionByName(F, "APlus512");
1903   Known = computeKnownBits(&APlus512, M->getDataLayout(), /* Depth */ 0, &AC,
1904                            F->front().getTerminator());
1905   // We know of one less zero because 512 may have produced a 1 that
1906   // got carried all the way to the first trailing zero.
1907   EXPECT_EQ(Known.Zero.getZExtValue(), (~(65536llu - 1)) << 1);
1908   EXPECT_EQ(Known.One.getZExtValue(), 0u);
1909   // The known range is not precise given computeKnownBits works
1910   // with the masks of zeros and ones, not the ranges.
1911   EXPECT_EQ(Known.getMinValue(), 0u);
1912   EXPECT_EQ(Known.getMaxValue(), 131071);
1913 }
1914 
1915 TEST_F(ComputeKnownBitsTest, ComputeKnownBitsUnknownVScale) {
1916   Module M("", Context);
1917   IRBuilder<> Builder(Context);
1918   Function *TheFn =
1919       Intrinsic::getDeclaration(&M, Intrinsic::vscale, {Builder.getInt32Ty()});
1920   CallInst *CI = Builder.CreateCall(TheFn, {}, {}, "");
1921 
1922   KnownBits Known = computeKnownBits(CI, M.getDataLayout(), /* Depth */ 0);
1923   // There is no parent function so we cannot look up the vscale_range
1924   // attribute to determine the number of bits.
1925   EXPECT_EQ(Known.One.getZExtValue(), 0u);
1926   EXPECT_EQ(Known.Zero.getZExtValue(), 0u);
1927 
1928   BasicBlock *BB = BasicBlock::Create(Context);
1929   CI->insertInto(BB, BB->end());
1930   Known = computeKnownBits(CI, M.getDataLayout(), /* Depth */ 0);
1931   // There is no parent function so we cannot look up the vscale_range
1932   // attribute to determine the number of bits.
1933   EXPECT_EQ(Known.One.getZExtValue(), 0u);
1934   EXPECT_EQ(Known.Zero.getZExtValue(), 0u);
1935 
1936   CI->removeFromParent();
1937   delete CI;
1938   delete BB;
1939 }
1940 
1941 // 512 + [32, 64) doesn't produce overlapping bits.
1942 // Make sure we get all the individual bits properly.
1943 TEST_F(ComputeKnownBitsTest, ComputeKnownBitsAddWithRangeNoOverlap) {
1944   parseAssembly("define void @test(i64* %p) {\n"
1945                 "  %A = load i64, i64* %p, !range !{i64 32, i64 64}\n"
1946                 "  %APlus512 = add i64 %A, 512\n"
1947                 "  %c = icmp ugt i64 %APlus512, 523\n"
1948                 "  call void @llvm.assume(i1 %c)\n"
1949                 "  ret void\n"
1950                 "}\n"
1951                 "declare void @llvm.assume(i1)\n");
1952   AssumptionCache AC(*F);
1953   KnownBits Known = computeKnownBits(A, M->getDataLayout(), /* Depth */ 0, &AC,
1954                                      F->front().getTerminator());
1955   EXPECT_EQ(Known.Zero.getZExtValue(), ~(64llu - 1));
1956   EXPECT_EQ(Known.One.getZExtValue(), 32u);
1957   Instruction &APlus512 = findInstructionByName(F, "APlus512");
1958   Known = computeKnownBits(&APlus512, M->getDataLayout(), /* Depth */ 0, &AC,
1959                            F->front().getTerminator());
1960   EXPECT_EQ(Known.Zero.getZExtValue(), ~512llu & ~(64llu - 1));
1961   EXPECT_EQ(Known.One.getZExtValue(), 512u | 32u);
1962   // The known range is not precise given computeKnownBits works
1963   // with the masks of zeros and ones, not the ranges.
1964   EXPECT_EQ(Known.getMinValue(), 544);
1965   EXPECT_EQ(Known.getMaxValue(), 575);
1966 }
1967 
1968 TEST_F(ComputeKnownBitsTest, ComputeKnownBitsGEPWithRange) {
1969   parseAssembly(
1970       "define void @test(i64* %p) {\n"
1971       "  %A = load i64, i64* %p, !range !{i64 64, i64 65536}\n"
1972       "  %APtr = inttoptr i64 %A to float*"
1973       "  %APtrPlus512 = getelementptr float, float* %APtr, i32 128\n"
1974       "  %c = icmp ugt float* %APtrPlus512, inttoptr (i32 523 to float*)\n"
1975       "  call void @llvm.assume(i1 %c)\n"
1976       "  ret void\n"
1977       "}\n"
1978       "declare void @llvm.assume(i1)\n");
1979   AssumptionCache AC(*F);
1980   KnownBits Known = computeKnownBits(A, M->getDataLayout(), /* Depth */ 0, &AC,
1981                                      F->front().getTerminator());
1982   EXPECT_EQ(Known.Zero.getZExtValue(), ~(65536llu - 1));
1983   EXPECT_EQ(Known.One.getZExtValue(), 0u);
1984   Instruction &APtrPlus512 = findInstructionByName(F, "APtrPlus512");
1985   Known = computeKnownBits(&APtrPlus512, M->getDataLayout(), /* Depth */ 0, &AC,
1986                            F->front().getTerminator());
1987   // We know of one less zero because 512 may have produced a 1 that
1988   // got carried all the way to the first trailing zero.
1989   EXPECT_EQ(Known.Zero.getZExtValue(), ~(65536llu - 1) << 1);
1990   EXPECT_EQ(Known.One.getZExtValue(), 0u);
1991   // The known range is not precise given computeKnownBits works
1992   // with the masks of zeros and ones, not the ranges.
1993   EXPECT_EQ(Known.getMinValue(), 0u);
1994   EXPECT_EQ(Known.getMaxValue(), 131071);
1995 }
1996 
1997 // 4*128 + [32, 64) doesn't produce overlapping bits.
1998 // Make sure we get all the individual bits properly.
1999 // This test is useful to check that we account for the scaling factor
2000 // in the gep. Indeed, gep float, [32,64), 128 is not 128 + [32,64).
2001 TEST_F(ComputeKnownBitsTest, ComputeKnownBitsGEPWithRangeNoOverlap) {
2002   parseAssembly(
2003       "define void @test(i64* %p) {\n"
2004       "  %A = load i64, i64* %p, !range !{i64 32, i64 64}\n"
2005       "  %APtr = inttoptr i64 %A to float*"
2006       "  %APtrPlus512 = getelementptr float, float* %APtr, i32 128\n"
2007       "  %c = icmp ugt float* %APtrPlus512, inttoptr (i32 523 to float*)\n"
2008       "  call void @llvm.assume(i1 %c)\n"
2009       "  ret void\n"
2010       "}\n"
2011       "declare void @llvm.assume(i1)\n");
2012   AssumptionCache AC(*F);
2013   KnownBits Known = computeKnownBits(A, M->getDataLayout(), /* Depth */ 0, &AC,
2014                                      F->front().getTerminator());
2015   EXPECT_EQ(Known.Zero.getZExtValue(), ~(64llu - 1));
2016   EXPECT_EQ(Known.One.getZExtValue(), 32u);
2017   Instruction &APtrPlus512 = findInstructionByName(F, "APtrPlus512");
2018   Known = computeKnownBits(&APtrPlus512, M->getDataLayout(), /* Depth */ 0, &AC,
2019                            F->front().getTerminator());
2020   EXPECT_EQ(Known.Zero.getZExtValue(), ~512llu & ~(64llu - 1));
2021   EXPECT_EQ(Known.One.getZExtValue(), 512u | 32u);
2022   // The known range is not precise given computeKnownBits works
2023   // with the masks of zeros and ones, not the ranges.
2024   EXPECT_EQ(Known.getMinValue(), 544);
2025   EXPECT_EQ(Known.getMaxValue(), 575);
2026 }
2027 
2028 TEST_F(ValueTrackingTest, HaveNoCommonBitsSet) {
2029   {
2030     // Check for an inverted mask: (X & ~M) op (Y & M).
2031     auto M = parseModule(R"(
2032   define i32 @test(i32 %X, i32 %Y, i32 %M) {
2033     %1 = xor i32 %M, -1
2034     %LHS = and i32 %1, %X
2035     %RHS = and i32 %Y, %M
2036     %Ret = add i32 %LHS, %RHS
2037     ret i32 %Ret
2038   })");
2039 
2040     auto *F = M->getFunction("test");
2041     auto *LHS = findInstructionByNameOrNull(F, "LHS");
2042     auto *RHS = findInstructionByNameOrNull(F, "RHS");
2043 
2044     const DataLayout &DL = M->getDataLayout();
2045     EXPECT_TRUE(haveNoCommonBitsSet(LHS, RHS, DL));
2046     EXPECT_TRUE(haveNoCommonBitsSet(RHS, LHS, DL));
2047   }
2048   {
2049     // Check for (A & B) and ~(A | B)
2050     auto M = parseModule(R"(
2051   define void @test(i32 %A, i32 %B) {
2052     %LHS = and i32 %A, %B
2053     %or = or i32 %A, %B
2054     %RHS = xor i32 %or, -1
2055 
2056     %LHS2 = and i32 %B, %A
2057     %or2 = or i32 %A, %B
2058     %RHS2 = xor i32 %or2, -1
2059 
2060     ret void
2061   })");
2062 
2063     auto *F = M->getFunction("test");
2064     const DataLayout &DL = M->getDataLayout();
2065 
2066     auto *LHS = findInstructionByNameOrNull(F, "LHS");
2067     auto *RHS = findInstructionByNameOrNull(F, "RHS");
2068     EXPECT_TRUE(haveNoCommonBitsSet(LHS, RHS, DL));
2069     EXPECT_TRUE(haveNoCommonBitsSet(RHS, LHS, DL));
2070 
2071     auto *LHS2 = findInstructionByNameOrNull(F, "LHS2");
2072     auto *RHS2 = findInstructionByNameOrNull(F, "RHS2");
2073     EXPECT_TRUE(haveNoCommonBitsSet(LHS2, RHS2, DL));
2074     EXPECT_TRUE(haveNoCommonBitsSet(RHS2, LHS2, DL));
2075   }
2076   {
2077     // Check for (A & B) and ~(A | B) in vector version
2078     auto M = parseModule(R"(
2079   define void @test(<2 x i32> %A, <2 x i32> %B) {
2080     %LHS = and <2 x i32> %A, %B
2081     %or = or <2 x i32> %A, %B
2082     %RHS = xor <2 x i32> %or, <i32 -1, i32 -1>
2083 
2084     %LHS2 = and <2 x i32> %B, %A
2085     %or2 = or <2 x i32> %A, %B
2086     %RHS2 = xor <2 x i32> %or2, <i32 -1, i32 -1>
2087 
2088     ret void
2089   })");
2090 
2091     auto *F = M->getFunction("test");
2092     const DataLayout &DL = M->getDataLayout();
2093 
2094     auto *LHS = findInstructionByNameOrNull(F, "LHS");
2095     auto *RHS = findInstructionByNameOrNull(F, "RHS");
2096     EXPECT_TRUE(haveNoCommonBitsSet(LHS, RHS, DL));
2097     EXPECT_TRUE(haveNoCommonBitsSet(RHS, LHS, DL));
2098 
2099     auto *LHS2 = findInstructionByNameOrNull(F, "LHS2");
2100     auto *RHS2 = findInstructionByNameOrNull(F, "RHS2");
2101     EXPECT_TRUE(haveNoCommonBitsSet(LHS2, RHS2, DL));
2102     EXPECT_TRUE(haveNoCommonBitsSet(RHS2, LHS2, DL));
2103   }
2104 }
2105 
2106 class IsBytewiseValueTest : public ValueTrackingTest,
2107                             public ::testing::WithParamInterface<
2108                                 std::pair<const char *, const char *>> {
2109 protected:
2110 };
2111 
2112 const std::pair<const char *, const char *> IsBytewiseValueTests[] = {
2113     {
2114         "i8 0",
2115         "i48* null",
2116     },
2117     {
2118         "i8 undef",
2119         "i48* undef",
2120     },
2121     {
2122         "i8 0",
2123         "i8 zeroinitializer",
2124     },
2125     {
2126         "i8 0",
2127         "i8 0",
2128     },
2129     {
2130         "i8 -86",
2131         "i8 -86",
2132     },
2133     {
2134         "i8 -1",
2135         "i8 -1",
2136     },
2137     {
2138         "i8 undef",
2139         "i16 undef",
2140     },
2141     {
2142         "i8 0",
2143         "i16 0",
2144     },
2145     {
2146         "",
2147         "i16 7",
2148     },
2149     {
2150         "i8 -86",
2151         "i16 -21846",
2152     },
2153     {
2154         "i8 -1",
2155         "i16 -1",
2156     },
2157     {
2158         "i8 0",
2159         "i48 0",
2160     },
2161     {
2162         "i8 -1",
2163         "i48 -1",
2164     },
2165     {
2166         "i8 0",
2167         "i49 0",
2168     },
2169     {
2170         "",
2171         "i49 -1",
2172     },
2173     {
2174         "i8 0",
2175         "half 0xH0000",
2176     },
2177     {
2178         "i8 -85",
2179         "half 0xHABAB",
2180     },
2181     {
2182         "i8 0",
2183         "float 0.0",
2184     },
2185     {
2186         "i8 -1",
2187         "float 0xFFFFFFFFE0000000",
2188     },
2189     {
2190         "i8 0",
2191         "double 0.0",
2192     },
2193     {
2194         "i8 -15",
2195         "double 0xF1F1F1F1F1F1F1F1",
2196     },
2197     {
2198         "i8 undef",
2199         "i16* undef",
2200     },
2201     {
2202         "i8 0",
2203         "i16* inttoptr (i64 0 to i16*)",
2204     },
2205     {
2206         "i8 -1",
2207         "i16* inttoptr (i64 -1 to i16*)",
2208     },
2209     {
2210         "i8 -86",
2211         "i16* inttoptr (i64 -6148914691236517206 to i16*)",
2212     },
2213     {
2214         "",
2215         "i16* inttoptr (i48 -1 to i16*)",
2216     },
2217     {
2218         "i8 -1",
2219         "i16* inttoptr (i96 -1 to i16*)",
2220     },
2221     {
2222         "i8 undef",
2223         "[0 x i8] zeroinitializer",
2224     },
2225     {
2226         "i8 undef",
2227         "[0 x i8] undef",
2228     },
2229     {
2230         "i8 undef",
2231         "[5 x [0 x i8]] zeroinitializer",
2232     },
2233     {
2234         "i8 undef",
2235         "[5 x [0 x i8]] undef",
2236     },
2237     {
2238         "i8 0",
2239         "[6 x i8] zeroinitializer",
2240     },
2241     {
2242         "i8 undef",
2243         "[6 x i8] undef",
2244     },
2245     {
2246         "i8 1",
2247         "[5 x i8] [i8 1, i8 1, i8 1, i8 1, i8 1]",
2248     },
2249     {
2250         "",
2251         "[5 x i64] [i64 1, i64 1, i64 1, i64 1, i64 1]",
2252     },
2253     {
2254         "i8 -1",
2255         "[5 x i64] [i64 -1, i64 -1, i64 -1, i64 -1, i64 -1]",
2256     },
2257     {
2258         "",
2259         "[4 x i8] [i8 1, i8 2, i8 1, i8 1]",
2260     },
2261     {
2262         "i8 1",
2263         "[4 x i8] [i8 1, i8 undef, i8 1, i8 1]",
2264     },
2265     {
2266         "i8 0",
2267         "<6 x i8> zeroinitializer",
2268     },
2269     {
2270         "i8 undef",
2271         "<6 x i8> undef",
2272     },
2273     {
2274         "i8 1",
2275         "<5 x i8> <i8 1, i8 1, i8 1, i8 1, i8 1>",
2276     },
2277     {
2278         "",
2279         "<5 x i64> <i64 1, i64 1, i64 1, i64 1, i64 1>",
2280     },
2281     {
2282         "i8 -1",
2283         "<5 x i64> <i64 -1, i64 -1, i64 -1, i64 -1, i64 -1>",
2284     },
2285     {
2286         "",
2287         "<4 x i8> <i8 1, i8 1, i8 2, i8 1>",
2288     },
2289     {
2290         "i8 5",
2291         "<2 x i8> < i8 5, i8 undef >",
2292     },
2293     {
2294         "i8 0",
2295         "[2 x [2 x i16]] zeroinitializer",
2296     },
2297     {
2298         "i8 undef",
2299         "[2 x [2 x i16]] undef",
2300     },
2301     {
2302         "i8 -86",
2303         "[2 x [2 x i16]] [[2 x i16] [i16 -21846, i16 -21846], "
2304         "[2 x i16] [i16 -21846, i16 -21846]]",
2305     },
2306     {
2307         "",
2308         "[2 x [2 x i16]] [[2 x i16] [i16 -21846, i16 -21846], "
2309         "[2 x i16] [i16 -21836, i16 -21846]]",
2310     },
2311     {
2312         "i8 undef",
2313         "{ } zeroinitializer",
2314     },
2315     {
2316         "i8 undef",
2317         "{ } undef",
2318     },
2319     {
2320         "i8 undef",
2321         "{ {}, {} } zeroinitializer",
2322     },
2323     {
2324         "i8 undef",
2325         "{ {}, {} } undef",
2326     },
2327     {
2328         "i8 0",
2329         "{i8, i64, i16*} zeroinitializer",
2330     },
2331     {
2332         "i8 undef",
2333         "{i8, i64, i16*} undef",
2334     },
2335     {
2336         "i8 -86",
2337         "{i8, i64, i16*} {i8 -86, i64 -6148914691236517206, i16* undef}",
2338     },
2339     {
2340         "",
2341         "{i8, i64, i16*} {i8 86, i64 -6148914691236517206, i16* undef}",
2342     },
2343 };
2344 
2345 INSTANTIATE_TEST_SUITE_P(IsBytewiseValueParamTests, IsBytewiseValueTest,
2346                          ::testing::ValuesIn(IsBytewiseValueTests));
2347 
2348 TEST_P(IsBytewiseValueTest, IsBytewiseValue) {
2349   auto M = parseModule(std::string("@test = global ") + GetParam().second);
2350   GlobalVariable *GV = dyn_cast<GlobalVariable>(M->getNamedValue("test"));
2351   Value *Actual = isBytewiseValue(GV->getInitializer(), M->getDataLayout());
2352   std::string Buff;
2353   raw_string_ostream S(Buff);
2354   if (Actual)
2355     S << *Actual;
2356   EXPECT_EQ(GetParam().first, S.str());
2357 }
2358 
2359 TEST_F(ValueTrackingTest, ComputeConstantRange) {
2360   {
2361     // Assumptions:
2362     //  * stride >= 5
2363     //  * stride < 10
2364     //
2365     // stride = [5, 10)
2366     auto M = parseModule(R"(
2367   declare void @llvm.assume(i1)
2368 
2369   define i32 @test(i32 %stride) {
2370     %gt = icmp uge i32 %stride, 5
2371     call void @llvm.assume(i1 %gt)
2372     %lt = icmp ult i32 %stride, 10
2373     call void @llvm.assume(i1 %lt)
2374     %stride.plus.one = add nsw nuw i32 %stride, 1
2375     ret i32 %stride.plus.one
2376   })");
2377     Function *F = M->getFunction("test");
2378 
2379     AssumptionCache AC(*F);
2380     Value *Stride = &*F->arg_begin();
2381     ConstantRange CR1 = computeConstantRange(Stride, false, true, &AC, nullptr);
2382     EXPECT_TRUE(CR1.isFullSet());
2383 
2384     Instruction *I = &findInstructionByName(F, "stride.plus.one");
2385     ConstantRange CR2 = computeConstantRange(Stride, false, true, &AC, I);
2386     EXPECT_EQ(5, CR2.getLower());
2387     EXPECT_EQ(10, CR2.getUpper());
2388   }
2389 
2390   {
2391     // Assumptions:
2392     //  * stride >= 5
2393     //  * stride < 200
2394     //  * stride == 99
2395     //
2396     // stride = [99, 100)
2397     auto M = parseModule(R"(
2398   declare void @llvm.assume(i1)
2399 
2400   define i32 @test(i32 %stride) {
2401     %gt = icmp uge i32 %stride, 5
2402     call void @llvm.assume(i1 %gt)
2403     %lt = icmp ult i32 %stride, 200
2404     call void @llvm.assume(i1 %lt)
2405     %eq = icmp eq i32 %stride, 99
2406     call void @llvm.assume(i1 %eq)
2407     %stride.plus.one = add nsw nuw i32 %stride, 1
2408     ret i32 %stride.plus.one
2409   })");
2410     Function *F = M->getFunction("test");
2411 
2412     AssumptionCache AC(*F);
2413     Value *Stride = &*F->arg_begin();
2414     Instruction *I = &findInstructionByName(F, "stride.plus.one");
2415     ConstantRange CR = computeConstantRange(Stride, false, true, &AC, I);
2416     EXPECT_EQ(99, *CR.getSingleElement());
2417   }
2418 
2419   {
2420     // Assumptions:
2421     //  * stride >= 5
2422     //  * stride >= 50
2423     //  * stride < 100
2424     //  * stride < 200
2425     //
2426     // stride = [50, 100)
2427     auto M = parseModule(R"(
2428   declare void @llvm.assume(i1)
2429 
2430   define i32 @test(i32 %stride, i1 %cond) {
2431     %gt = icmp uge i32 %stride, 5
2432     call void @llvm.assume(i1 %gt)
2433     %gt.2 = icmp uge i32 %stride, 50
2434     call void @llvm.assume(i1 %gt.2)
2435     br i1 %cond, label %bb1, label %bb2
2436 
2437   bb1:
2438     %lt = icmp ult i32 %stride, 200
2439     call void @llvm.assume(i1 %lt)
2440     %lt.2 = icmp ult i32 %stride, 100
2441     call void @llvm.assume(i1 %lt.2)
2442     %stride.plus.one = add nsw nuw i32 %stride, 1
2443     ret i32 %stride.plus.one
2444 
2445   bb2:
2446     ret i32 0
2447   })");
2448     Function *F = M->getFunction("test");
2449 
2450     AssumptionCache AC(*F);
2451     Value *Stride = &*F->arg_begin();
2452     Instruction *GT2 = &findInstructionByName(F, "gt.2");
2453     ConstantRange CR = computeConstantRange(Stride, false, true, &AC, GT2);
2454     EXPECT_EQ(5, CR.getLower());
2455     EXPECT_EQ(0, CR.getUpper());
2456 
2457     Instruction *I = &findInstructionByName(F, "stride.plus.one");
2458     ConstantRange CR2 = computeConstantRange(Stride, false, true, &AC, I);
2459     EXPECT_EQ(50, CR2.getLower());
2460     EXPECT_EQ(100, CR2.getUpper());
2461   }
2462 
2463   {
2464     // Assumptions:
2465     //  * stride > 5
2466     //  * stride < 5
2467     //
2468     // stride = empty range, as the assumptions contradict each other.
2469     auto M = parseModule(R"(
2470   declare void @llvm.assume(i1)
2471 
2472   define i32 @test(i32 %stride, i1 %cond) {
2473     %gt = icmp ugt i32 %stride, 5
2474     call void @llvm.assume(i1 %gt)
2475     %lt = icmp ult i32 %stride, 5
2476     call void @llvm.assume(i1 %lt)
2477     %stride.plus.one = add nsw nuw i32 %stride, 1
2478     ret i32 %stride.plus.one
2479   })");
2480     Function *F = M->getFunction("test");
2481 
2482     AssumptionCache AC(*F);
2483     Value *Stride = &*F->arg_begin();
2484 
2485     Instruction *I = &findInstructionByName(F, "stride.plus.one");
2486     ConstantRange CR = computeConstantRange(Stride, false, true, &AC, I);
2487     EXPECT_TRUE(CR.isEmptySet());
2488   }
2489 
2490   {
2491     // Assumptions:
2492     //  * x.1 >= 5
2493     //  * x.2 < x.1
2494     //
2495     // stride = [0, -1)
2496     auto M = parseModule(R"(
2497   declare void @llvm.assume(i1)
2498 
2499   define i32 @test(i32 %x.1, i32 %x.2) {
2500     %gt = icmp uge i32 %x.1, 5
2501     call void @llvm.assume(i1 %gt)
2502     %lt = icmp ult i32 %x.2, %x.1
2503     call void @llvm.assume(i1 %lt)
2504     %stride.plus.one = add nsw nuw i32 %x.1, 1
2505     ret i32 %stride.plus.one
2506   })");
2507     Function *F = M->getFunction("test");
2508 
2509     AssumptionCache AC(*F);
2510     Value *X1 = &*(F->arg_begin());
2511     Value *X2 = &*std::next(F->arg_begin());
2512 
2513     Instruction *I = &findInstructionByName(F, "stride.plus.one");
2514     ConstantRange CR1 = computeConstantRange(X1, false, true, &AC, I);
2515     ConstantRange CR2 = computeConstantRange(X2, false, true, &AC, I);
2516 
2517     EXPECT_EQ(5, CR1.getLower());
2518     EXPECT_EQ(0, CR1.getUpper());
2519 
2520     EXPECT_EQ(0, CR2.getLower());
2521     EXPECT_EQ(0xffffffff, CR2.getUpper());
2522 
2523     // Check the depth cutoff results in a conservative result (full set) by
2524     // passing Depth == MaxDepth == 6.
2525     ConstantRange CR3 = computeConstantRange(X2, false, true, &AC, I, nullptr, 6);
2526     EXPECT_TRUE(CR3.isFullSet());
2527   }
2528   {
2529     // Assumptions:
2530     //  * x.2 <= x.1
2531     auto M = parseModule(R"(
2532   declare void @llvm.assume(i1)
2533 
2534   define i32 @test(i32 %x.1, i32 %x.2) {
2535     %lt = icmp ule i32 %x.2, %x.1
2536     call void @llvm.assume(i1 %lt)
2537     %stride.plus.one = add nsw nuw i32 %x.1, 1
2538     ret i32 %stride.plus.one
2539   })");
2540     Function *F = M->getFunction("test");
2541 
2542     AssumptionCache AC(*F);
2543     Value *X2 = &*std::next(F->arg_begin());
2544 
2545     Instruction *I = &findInstructionByName(F, "stride.plus.one");
2546     ConstantRange CR1 = computeConstantRange(X2, false, true, &AC, I);
2547     // If we don't know the value of x.2, we don't know the value of x.1.
2548     EXPECT_TRUE(CR1.isFullSet());
2549   }
2550 }
2551 
2552 struct FindAllocaForValueTestParams {
2553   const char *IR;
2554   bool AnyOffsetResult;
2555   bool ZeroOffsetResult;
2556 };
2557 
2558 class FindAllocaForValueTest
2559     : public ValueTrackingTest,
2560       public ::testing::WithParamInterface<FindAllocaForValueTestParams> {
2561 protected:
2562 };
2563 
2564 const FindAllocaForValueTestParams FindAllocaForValueTests[] = {
2565     {R"(
2566       define void @test() {
2567         %a = alloca i64
2568         %r = bitcast i64* %a to i32*
2569         ret void
2570       })",
2571      true, true},
2572 
2573     {R"(
2574       define void @test() {
2575         %a = alloca i32
2576         %r = getelementptr i32, i32* %a, i32 1
2577         ret void
2578       })",
2579      true, false},
2580 
2581     {R"(
2582       define void @test() {
2583         %a = alloca i32
2584         %r = getelementptr i32, i32* %a, i32 0
2585         ret void
2586       })",
2587      true, true},
2588 
2589     {R"(
2590       define void @test(i1 %cond) {
2591       entry:
2592         %a = alloca i32
2593         br label %bb1
2594 
2595       bb1:
2596         %r = phi i32* [ %a, %entry ], [ %r, %bb1 ]
2597         br i1 %cond, label %bb1, label %exit
2598 
2599       exit:
2600         ret void
2601       })",
2602      true, true},
2603 
2604     {R"(
2605       define void @test(i1 %cond) {
2606         %a = alloca i32
2607         %r = select i1 %cond, i32* %a, i32* %a
2608         ret void
2609       })",
2610      true, true},
2611 
2612     {R"(
2613       define void @test(i1 %cond) {
2614         %a = alloca i32
2615         %b = alloca i32
2616         %r = select i1 %cond, i32* %a, i32* %b
2617         ret void
2618       })",
2619      false, false},
2620 
2621     {R"(
2622       define void @test(i1 %cond) {
2623       entry:
2624         %a = alloca i64
2625         %a32 = bitcast i64* %a to i32*
2626         br label %bb1
2627 
2628       bb1:
2629         %x = phi i32* [ %a32, %entry ], [ %x, %bb1 ]
2630         %r = getelementptr i32, i32* %x, i32 1
2631         br i1 %cond, label %bb1, label %exit
2632 
2633       exit:
2634         ret void
2635       })",
2636      true, false},
2637 
2638     {R"(
2639       define void @test(i1 %cond) {
2640       entry:
2641         %a = alloca i64
2642         %a32 = bitcast i64* %a to i32*
2643         br label %bb1
2644 
2645       bb1:
2646         %x = phi i32* [ %a32, %entry ], [ %r, %bb1 ]
2647         %r = getelementptr i32, i32* %x, i32 1
2648         br i1 %cond, label %bb1, label %exit
2649 
2650       exit:
2651         ret void
2652       })",
2653      true, false},
2654 
2655     {R"(
2656       define void @test(i1 %cond, i64* %a) {
2657       entry:
2658         %r = bitcast i64* %a to i32*
2659         ret void
2660       })",
2661      false, false},
2662 
2663     {R"(
2664       define void @test(i1 %cond) {
2665       entry:
2666         %a = alloca i32
2667         %b = alloca i32
2668         br label %bb1
2669 
2670       bb1:
2671         %r = phi i32* [ %a, %entry ], [ %b, %bb1 ]
2672         br i1 %cond, label %bb1, label %exit
2673 
2674       exit:
2675         ret void
2676       })",
2677      false, false},
2678     {R"(
2679       declare i32* @retptr(i32* returned)
2680       define void @test(i1 %cond) {
2681         %a = alloca i32
2682         %r = call i32* @retptr(i32* %a)
2683         ret void
2684       })",
2685      true, true},
2686     {R"(
2687       declare i32* @fun(i32*)
2688       define void @test(i1 %cond) {
2689         %a = alloca i32
2690         %r = call i32* @fun(i32* %a)
2691         ret void
2692       })",
2693      false, false},
2694 };
2695 
2696 TEST_P(FindAllocaForValueTest, findAllocaForValue) {
2697   auto M = parseModule(GetParam().IR);
2698   Function *F = M->getFunction("test");
2699   Instruction *I = &findInstructionByName(F, "r");
2700   const AllocaInst *AI = findAllocaForValue(I);
2701   EXPECT_EQ(!!AI, GetParam().AnyOffsetResult);
2702 }
2703 
2704 TEST_P(FindAllocaForValueTest, findAllocaForValueZeroOffset) {
2705   auto M = parseModule(GetParam().IR);
2706   Function *F = M->getFunction("test");
2707   Instruction *I = &findInstructionByName(F, "r");
2708   const AllocaInst *AI = findAllocaForValue(I, true);
2709   EXPECT_EQ(!!AI, GetParam().ZeroOffsetResult);
2710 }
2711 
2712 INSTANTIATE_TEST_SUITE_P(FindAllocaForValueTest, FindAllocaForValueTest,
2713                          ::testing::ValuesIn(FindAllocaForValueTests));
2714