xref: /llvm-project/llvm/unittests/Analysis/ValueTrackingTest.cpp (revision 5c3496ff33ce8e4cc6f8c18edd7ae5fc65d23fdf)
1 //===- ValueTrackingTest.cpp - ValueTracking tests ------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "llvm/Analysis/ValueTracking.h"
10 #include "llvm/Analysis/AssumptionCache.h"
11 #include "llvm/AsmParser/Parser.h"
12 #include "llvm/IR/ConstantRange.h"
13 #include "llvm/IR/Dominators.h"
14 #include "llvm/IR/Function.h"
15 #include "llvm/IR/IRBuilder.h"
16 #include "llvm/IR/InstIterator.h"
17 #include "llvm/IR/Instructions.h"
18 #include "llvm/IR/LLVMContext.h"
19 #include "llvm/IR/Module.h"
20 #include "llvm/Support/ErrorHandling.h"
21 #include "llvm/Support/KnownBits.h"
22 #include "llvm/Support/SourceMgr.h"
23 #include "llvm/Transforms/Utils/Local.h"
24 #include "gtest/gtest.h"
25 
26 using namespace llvm;
27 
28 namespace {
29 
30 static Instruction *findInstructionByNameOrNull(Function *F, StringRef Name) {
31   for (Instruction &I : instructions(F))
32     if (I.getName() == Name)
33       return &I;
34 
35   return nullptr;
36 }
37 
38 static Instruction &findInstructionByName(Function *F, StringRef Name) {
39   auto *I = findInstructionByNameOrNull(F, Name);
40   if (I)
41     return *I;
42 
43   llvm_unreachable("Expected value not found");
44 }
45 
46 class ValueTrackingTest : public testing::Test {
47 protected:
48   std::unique_ptr<Module> parseModule(StringRef Assembly) {
49     SMDiagnostic Error;
50     std::unique_ptr<Module> M = parseAssemblyString(Assembly, Error, Context);
51 
52     std::string errMsg;
53     raw_string_ostream os(errMsg);
54     Error.print("", os);
55     EXPECT_TRUE(M) << os.str();
56 
57     return M;
58   }
59 
60   void parseAssembly(StringRef Assembly) {
61     M = parseModule(Assembly);
62     ASSERT_TRUE(M);
63 
64     F = M->getFunction("test");
65     ASSERT_TRUE(F) << "Test must have a function @test";
66     if (!F)
67       return;
68 
69     A = findInstructionByNameOrNull(F, "A");
70     ASSERT_TRUE(A) << "@test must have an instruction %A";
71     A2 = findInstructionByNameOrNull(F, "A2");
72     A3 = findInstructionByNameOrNull(F, "A3");
73     A4 = findInstructionByNameOrNull(F, "A4");
74     A5 = findInstructionByNameOrNull(F, "A5");
75     A6 = findInstructionByNameOrNull(F, "A6");
76     A7 = findInstructionByNameOrNull(F, "A7");
77 
78     CxtI = findInstructionByNameOrNull(F, "CxtI");
79     CxtI2 = findInstructionByNameOrNull(F, "CxtI2");
80     CxtI3 = findInstructionByNameOrNull(F, "CxtI3");
81   }
82 
83   LLVMContext Context;
84   std::unique_ptr<Module> M;
85   Function *F = nullptr;
86   Instruction *A = nullptr;
87   // Instructions (optional)
88   Instruction *A2 = nullptr, *A3 = nullptr, *A4 = nullptr, *A5 = nullptr,
89               *A6 = nullptr, *A7 = nullptr;
90 
91   // Context instructions (optional)
92   Instruction *CxtI = nullptr, *CxtI2 = nullptr, *CxtI3 = nullptr;
93 };
94 
95 class MatchSelectPatternTest : public ValueTrackingTest {
96 protected:
97   void expectPattern(const SelectPatternResult &P) {
98     Value *LHS, *RHS;
99     Instruction::CastOps CastOp;
100     SelectPatternResult R = matchSelectPattern(A, LHS, RHS, &CastOp);
101     EXPECT_EQ(P.Flavor, R.Flavor);
102     EXPECT_EQ(P.NaNBehavior, R.NaNBehavior);
103     EXPECT_EQ(P.Ordered, R.Ordered);
104   }
105 };
106 
107 class ComputeKnownBitsTest : public ValueTrackingTest {
108 protected:
109   void expectKnownBits(uint64_t Zero, uint64_t One) {
110     auto Known = computeKnownBits(A, M->getDataLayout());
111     ASSERT_FALSE(Known.hasConflict());
112     EXPECT_EQ(Known.One.getZExtValue(), One);
113     EXPECT_EQ(Known.Zero.getZExtValue(), Zero);
114   }
115 };
116 
117 class ComputeKnownFPClassTest : public ValueTrackingTest {
118 protected:
119   void expectKnownFPClass(unsigned KnownTrue, std::optional<bool> SignBitKnown,
120                           Instruction *TestVal = nullptr) {
121     if (!TestVal)
122       TestVal = A;
123 
124     KnownFPClass Known = computeKnownFPClass(TestVal, M->getDataLayout());
125     EXPECT_EQ(KnownTrue, Known.KnownFPClasses);
126     EXPECT_EQ(SignBitKnown, Known.SignBit);
127   }
128 };
129 }
130 
131 TEST_F(MatchSelectPatternTest, SimpleFMin) {
132   parseAssembly(
133       "define float @test(float %a) {\n"
134       "  %1 = fcmp ult float %a, 5.0\n"
135       "  %A = select i1 %1, float %a, float 5.0\n"
136       "  ret float %A\n"
137       "}\n");
138   expectPattern({SPF_FMINNUM, SPNB_RETURNS_NAN, false});
139 }
140 
141 TEST_F(MatchSelectPatternTest, SimpleFMax) {
142   parseAssembly(
143       "define float @test(float %a) {\n"
144       "  %1 = fcmp ogt float %a, 5.0\n"
145       "  %A = select i1 %1, float %a, float 5.0\n"
146       "  ret float %A\n"
147       "}\n");
148   expectPattern({SPF_FMAXNUM, SPNB_RETURNS_OTHER, true});
149 }
150 
151 TEST_F(MatchSelectPatternTest, SwappedFMax) {
152   parseAssembly(
153       "define float @test(float %a) {\n"
154       "  %1 = fcmp olt float 5.0, %a\n"
155       "  %A = select i1 %1, float %a, float 5.0\n"
156       "  ret float %A\n"
157       "}\n");
158   expectPattern({SPF_FMAXNUM, SPNB_RETURNS_OTHER, false});
159 }
160 
161 TEST_F(MatchSelectPatternTest, SwappedFMax2) {
162   parseAssembly(
163       "define float @test(float %a) {\n"
164       "  %1 = fcmp olt float %a, 5.0\n"
165       "  %A = select i1 %1, float 5.0, float %a\n"
166       "  ret float %A\n"
167       "}\n");
168   expectPattern({SPF_FMAXNUM, SPNB_RETURNS_NAN, false});
169 }
170 
171 TEST_F(MatchSelectPatternTest, SwappedFMax3) {
172   parseAssembly(
173       "define float @test(float %a) {\n"
174       "  %1 = fcmp ult float %a, 5.0\n"
175       "  %A = select i1 %1, float 5.0, float %a\n"
176       "  ret float %A\n"
177       "}\n");
178   expectPattern({SPF_FMAXNUM, SPNB_RETURNS_OTHER, true});
179 }
180 
181 TEST_F(MatchSelectPatternTest, FastFMin) {
182   parseAssembly(
183       "define float @test(float %a) {\n"
184       "  %1 = fcmp nnan olt float %a, 5.0\n"
185       "  %A = select i1 %1, float %a, float 5.0\n"
186       "  ret float %A\n"
187       "}\n");
188   expectPattern({SPF_FMINNUM, SPNB_RETURNS_ANY, false});
189 }
190 
191 TEST_F(MatchSelectPatternTest, FMinConstantZero) {
192   parseAssembly(
193       "define float @test(float %a) {\n"
194       "  %1 = fcmp ole float %a, 0.0\n"
195       "  %A = select i1 %1, float %a, float 0.0\n"
196       "  ret float %A\n"
197       "}\n");
198   // This shouldn't be matched, as %a could be -0.0.
199   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
200 }
201 
202 TEST_F(MatchSelectPatternTest, FMinConstantZeroNsz) {
203   parseAssembly(
204       "define float @test(float %a) {\n"
205       "  %1 = fcmp nsz ole float %a, 0.0\n"
206       "  %A = select i1 %1, float %a, float 0.0\n"
207       "  ret float %A\n"
208       "}\n");
209   // But this should be, because we've ignored signed zeroes.
210   expectPattern({SPF_FMINNUM, SPNB_RETURNS_OTHER, true});
211 }
212 
213 TEST_F(MatchSelectPatternTest, FMinMismatchConstantZero1) {
214   parseAssembly(
215       "define float @test(float %a) {\n"
216       "  %1 = fcmp olt float -0.0, %a\n"
217       "  %A = select i1 %1, float 0.0, float %a\n"
218       "  ret float %A\n"
219       "}\n");
220   // The sign of zero doesn't matter in fcmp.
221   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
222 }
223 
224 TEST_F(MatchSelectPatternTest, FMinMismatchConstantZero2) {
225   parseAssembly(
226       "define float @test(float %a) {\n"
227       "  %1 = fcmp ogt float %a, -0.0\n"
228       "  %A = select i1 %1, float 0.0, float %a\n"
229       "  ret float %A\n"
230       "}\n");
231   // The sign of zero doesn't matter in fcmp.
232   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
233 }
234 
235 TEST_F(MatchSelectPatternTest, FMinMismatchConstantZero3) {
236   parseAssembly(
237       "define float @test(float %a) {\n"
238       "  %1 = fcmp olt float 0.0, %a\n"
239       "  %A = select i1 %1, float -0.0, float %a\n"
240       "  ret float %A\n"
241       "}\n");
242   // The sign of zero doesn't matter in fcmp.
243   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
244 }
245 
246 TEST_F(MatchSelectPatternTest, FMinMismatchConstantZero4) {
247   parseAssembly(
248       "define float @test(float %a) {\n"
249       "  %1 = fcmp ogt float %a, 0.0\n"
250       "  %A = select i1 %1, float -0.0, float %a\n"
251       "  ret float %A\n"
252       "}\n");
253   // The sign of zero doesn't matter in fcmp.
254   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
255 }
256 
257 TEST_F(MatchSelectPatternTest, FMinMismatchConstantZero5) {
258   parseAssembly(
259       "define float @test(float %a) {\n"
260       "  %1 = fcmp ogt float -0.0, %a\n"
261       "  %A = select i1 %1, float %a, float 0.0\n"
262       "  ret float %A\n"
263       "}\n");
264   // The sign of zero doesn't matter in fcmp.
265   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
266 }
267 
268 TEST_F(MatchSelectPatternTest, FMinMismatchConstantZero6) {
269   parseAssembly(
270       "define float @test(float %a) {\n"
271       "  %1 = fcmp olt float %a, -0.0\n"
272       "  %A = select i1 %1, float %a, float 0.0\n"
273       "  ret float %A\n"
274       "}\n");
275   // The sign of zero doesn't matter in fcmp.
276   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
277 }
278 
279 TEST_F(MatchSelectPatternTest, FMinMismatchConstantZero7) {
280   parseAssembly(
281       "define float @test(float %a) {\n"
282       "  %1 = fcmp ogt float 0.0, %a\n"
283       "  %A = select i1 %1, float %a, float -0.0\n"
284       "  ret float %A\n"
285       "}\n");
286   // The sign of zero doesn't matter in fcmp.
287   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
288 }
289 
290 TEST_F(MatchSelectPatternTest, FMinMismatchConstantZero8) {
291   parseAssembly(
292       "define float @test(float %a) {\n"
293       "  %1 = fcmp olt float %a, 0.0\n"
294       "  %A = select i1 %1, float %a, float -0.0\n"
295       "  ret float %A\n"
296       "}\n");
297   // The sign of zero doesn't matter in fcmp.
298   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
299 }
300 
301 TEST_F(MatchSelectPatternTest, FMaxMismatchConstantZero1) {
302   parseAssembly(
303       "define float @test(float %a) {\n"
304       "  %1 = fcmp ogt float -0.0, %a\n"
305       "  %A = select i1 %1, float 0.0, float %a\n"
306       "  ret float %A\n"
307       "}\n");
308   // The sign of zero doesn't matter in fcmp.
309   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
310 }
311 
312 TEST_F(MatchSelectPatternTest, FMaxMismatchConstantZero2) {
313   parseAssembly(
314       "define float @test(float %a) {\n"
315       "  %1 = fcmp olt float %a, -0.0\n"
316       "  %A = select i1 %1, float 0.0, float %a\n"
317       "  ret float %A\n"
318       "}\n");
319   // The sign of zero doesn't matter in fcmp.
320   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
321 }
322 
323 TEST_F(MatchSelectPatternTest, FMaxMismatchConstantZero3) {
324   parseAssembly(
325       "define float @test(float %a) {\n"
326       "  %1 = fcmp ogt float 0.0, %a\n"
327       "  %A = select i1 %1, float -0.0, float %a\n"
328       "  ret float %A\n"
329       "}\n");
330   // The sign of zero doesn't matter in fcmp.
331   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
332 }
333 
334 TEST_F(MatchSelectPatternTest, FMaxMismatchConstantZero4) {
335   parseAssembly(
336       "define float @test(float %a) {\n"
337       "  %1 = fcmp olt float %a, 0.0\n"
338       "  %A = select i1 %1, float -0.0, float %a\n"
339       "  ret float %A\n"
340       "}\n");
341   // The sign of zero doesn't matter in fcmp.
342   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
343 }
344 
345 TEST_F(MatchSelectPatternTest, FMaxMismatchConstantZero5) {
346   parseAssembly(
347       "define float @test(float %a) {\n"
348       "  %1 = fcmp olt float -0.0, %a\n"
349       "  %A = select i1 %1, float %a, float 0.0\n"
350       "  ret float %A\n"
351       "}\n");
352   // The sign of zero doesn't matter in fcmp.
353   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
354 }
355 
356 TEST_F(MatchSelectPatternTest, FMaxMismatchConstantZero6) {
357   parseAssembly(
358       "define float @test(float %a) {\n"
359       "  %1 = fcmp ogt float %a, -0.0\n"
360       "  %A = select i1 %1, float %a, float 0.0\n"
361       "  ret float %A\n"
362       "}\n");
363   // The sign of zero doesn't matter in fcmp.
364   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
365 }
366 
367 TEST_F(MatchSelectPatternTest, FMaxMismatchConstantZero7) {
368   parseAssembly(
369       "define float @test(float %a) {\n"
370       "  %1 = fcmp olt float 0.0, %a\n"
371       "  %A = select i1 %1, float %a, float -0.0\n"
372       "  ret float %A\n"
373       "}\n");
374   // The sign of zero doesn't matter in fcmp.
375   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
376 }
377 
378 TEST_F(MatchSelectPatternTest, FMaxMismatchConstantZero8) {
379   parseAssembly(
380       "define float @test(float %a) {\n"
381       "  %1 = fcmp ogt float %a, 0.0\n"
382       "  %A = select i1 %1, float %a, float -0.0\n"
383       "  ret float %A\n"
384       "}\n");
385   // The sign of zero doesn't matter in fcmp.
386   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
387 }
388 
389 TEST_F(MatchSelectPatternTest, FMinMismatchConstantZeroVecUndef) {
390   parseAssembly(
391       "define <2 x float> @test(<2 x float> %a) {\n"
392       "  %1 = fcmp ogt <2 x float> %a, <float -0.0, float -0.0>\n"
393       "  %A = select <2 x i1> %1, <2 x float> <float undef, float 0.0>, <2 x float> %a\n"
394       "  ret <2 x float> %A\n"
395       "}\n");
396   // An undef in a vector constant can not be back-propagated for this analysis.
397   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
398 }
399 
400 TEST_F(MatchSelectPatternTest, FMaxMismatchConstantZeroVecUndef) {
401   parseAssembly(
402       "define <2 x float> @test(<2 x float> %a) {\n"
403       "  %1 = fcmp ogt <2 x float> %a, zeroinitializer\n"
404       "  %A = select <2 x i1> %1, <2 x float> %a, <2 x float> <float -0.0, float undef>\n"
405       "  ret <2 x float> %A\n"
406       "}\n");
407   // An undef in a vector constant can not be back-propagated for this analysis.
408   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
409 }
410 
411 TEST_F(MatchSelectPatternTest, VectorFMinimum) {
412   parseAssembly(
413       "define <4 x float> @test(<4 x float> %a) {\n"
414       "  %1 = fcmp ule <4 x float> %a, \n"
415       "    <float 5.0, float 5.0, float 5.0, float 5.0>\n"
416       "  %A = select <4 x i1> %1, <4 x float> %a,\n"
417       "     <4 x float> <float 5.0, float 5.0, float 5.0, float 5.0>\n"
418       "  ret <4 x float> %A\n"
419       "}\n");
420   // Check that pattern matching works on vectors where each lane has the same
421   // unordered pattern.
422   expectPattern({SPF_FMINNUM, SPNB_RETURNS_NAN, false});
423 }
424 
425 TEST_F(MatchSelectPatternTest, VectorFMinOtherOrdered) {
426   parseAssembly(
427       "define <4 x float> @test(<4 x float> %a) {\n"
428       "  %1 = fcmp ole <4 x float> %a, \n"
429       "    <float 5.0, float 5.0, float 5.0, float 5.0>\n"
430       "  %A = select <4 x i1> %1, <4 x float> %a,\n"
431       "     <4 x float> <float 5.0, float 5.0, float 5.0, float 5.0>\n"
432       "  ret <4 x float> %A\n"
433       "}\n");
434   // Check that pattern matching works on vectors where each lane has the same
435   // ordered pattern.
436   expectPattern({SPF_FMINNUM, SPNB_RETURNS_OTHER, true});
437 }
438 
439 TEST_F(MatchSelectPatternTest, VectorNotFMinimum) {
440   parseAssembly(
441       "define <4 x float> @test(<4 x float> %a) {\n"
442       "  %1 = fcmp ule <4 x float> %a, \n"
443       "    <float 5.0, float 0x7ff8000000000000, float 5.0, float 5.0>\n"
444       "  %A = select <4 x i1> %1, <4 x float> %a,\n"
445       "     <4 x float> <float 5.0, float 0x7ff8000000000000, float 5.0, float "
446       "5.0>\n"
447       "  ret <4 x float> %A\n"
448       "}\n");
449   // The lane that contains a NaN (0x7ff80...) behaves like a
450   // non-NaN-propagating min and the other lines behave like a NaN-propagating
451   // min, so check that neither is returned.
452   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
453 }
454 
455 TEST_F(MatchSelectPatternTest, VectorNotFMinZero) {
456   parseAssembly(
457       "define <4 x float> @test(<4 x float> %a) {\n"
458       "  %1 = fcmp ule <4 x float> %a, \n"
459       "    <float 5.0, float -0.0, float 5.0, float 5.0>\n"
460       "  %A = select <4 x i1> %1, <4 x float> %a,\n"
461       "     <4 x float> <float 5.0, float 0.0, float 5.0, float 5.0>\n"
462       "  ret <4 x float> %A\n"
463       "}\n");
464   // Always selects the second lane of %a if it is positive or negative zero, so
465   // this is stricter than a min.
466   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
467 }
468 
469 TEST_F(MatchSelectPatternTest, DoubleCastU) {
470   parseAssembly(
471       "define i32 @test(i8 %a, i8 %b) {\n"
472       "  %1 = icmp ult i8 %a, %b\n"
473       "  %2 = zext i8 %a to i32\n"
474       "  %3 = zext i8 %b to i32\n"
475       "  %A = select i1 %1, i32 %2, i32 %3\n"
476       "  ret i32 %A\n"
477       "}\n");
478   // We should be able to look through the situation where we cast both operands
479   // to the select.
480   expectPattern({SPF_UMIN, SPNB_NA, false});
481 }
482 
483 TEST_F(MatchSelectPatternTest, DoubleCastS) {
484   parseAssembly(
485       "define i32 @test(i8 %a, i8 %b) {\n"
486       "  %1 = icmp slt i8 %a, %b\n"
487       "  %2 = sext i8 %a to i32\n"
488       "  %3 = sext i8 %b to i32\n"
489       "  %A = select i1 %1, i32 %2, i32 %3\n"
490       "  ret i32 %A\n"
491       "}\n");
492   // We should be able to look through the situation where we cast both operands
493   // to the select.
494   expectPattern({SPF_SMIN, SPNB_NA, false});
495 }
496 
497 TEST_F(MatchSelectPatternTest, DoubleCastBad) {
498   parseAssembly(
499       "define i32 @test(i8 %a, i8 %b) {\n"
500       "  %1 = icmp ult i8 %a, %b\n"
501       "  %2 = zext i8 %a to i32\n"
502       "  %3 = sext i8 %b to i32\n"
503       "  %A = select i1 %1, i32 %2, i32 %3\n"
504       "  ret i32 %A\n"
505       "}\n");
506   // The cast types here aren't the same, so we cannot match an UMIN.
507   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
508 }
509 
510 TEST_F(MatchSelectPatternTest, NotNotSMin) {
511   parseAssembly(
512       "define i8 @test(i8 %a, i8 %b) {\n"
513       "  %cmp = icmp sgt i8 %a, %b\n"
514       "  %an = xor i8 %a, -1\n"
515       "  %bn = xor i8 %b, -1\n"
516       "  %A = select i1 %cmp, i8 %an, i8 %bn\n"
517       "  ret i8 %A\n"
518       "}\n");
519   expectPattern({SPF_SMIN, SPNB_NA, false});
520 }
521 
522 TEST_F(MatchSelectPatternTest, NotNotSMinSwap) {
523   parseAssembly(
524       "define <2 x i8> @test(<2 x i8> %a, <2 x i8> %b) {\n"
525       "  %cmp = icmp slt <2 x i8> %a, %b\n"
526       "  %an = xor <2 x i8> %a, <i8 -1, i8-1>\n"
527       "  %bn = xor <2 x i8> %b, <i8 -1, i8-1>\n"
528       "  %A = select <2 x i1> %cmp, <2 x i8> %bn, <2 x i8> %an\n"
529       "  ret <2 x i8> %A\n"
530       "}\n");
531   expectPattern({SPF_SMIN, SPNB_NA, false});
532 }
533 
534 TEST_F(MatchSelectPatternTest, NotNotSMax) {
535   parseAssembly(
536       "define i8 @test(i8 %a, i8 %b) {\n"
537       "  %cmp = icmp slt i8 %a, %b\n"
538       "  %an = xor i8 %a, -1\n"
539       "  %bn = xor i8 %b, -1\n"
540       "  %A = select i1 %cmp, i8 %an, i8 %bn\n"
541       "  ret i8 %A\n"
542       "}\n");
543   expectPattern({SPF_SMAX, SPNB_NA, false});
544 }
545 
546 TEST_F(MatchSelectPatternTest, NotNotSMaxSwap) {
547   parseAssembly(
548       "define <2 x i8> @test(<2 x i8> %a, <2 x i8> %b) {\n"
549       "  %cmp = icmp sgt <2 x i8> %a, %b\n"
550       "  %an = xor <2 x i8> %a, <i8 -1, i8-1>\n"
551       "  %bn = xor <2 x i8> %b, <i8 -1, i8-1>\n"
552       "  %A = select <2 x i1> %cmp, <2 x i8> %bn, <2 x i8> %an\n"
553       "  ret <2 x i8> %A\n"
554       "}\n");
555   expectPattern({SPF_SMAX, SPNB_NA, false});
556 }
557 
558 TEST_F(MatchSelectPatternTest, NotNotUMin) {
559   parseAssembly(
560       "define <2 x i8> @test(<2 x i8> %a, <2 x i8> %b) {\n"
561       "  %cmp = icmp ugt <2 x i8> %a, %b\n"
562       "  %an = xor <2 x i8> %a, <i8 -1, i8-1>\n"
563       "  %bn = xor <2 x i8> %b, <i8 -1, i8-1>\n"
564       "  %A = select <2 x i1> %cmp, <2 x i8> %an, <2 x i8> %bn\n"
565       "  ret <2 x i8> %A\n"
566       "}\n");
567   expectPattern({SPF_UMIN, SPNB_NA, false});
568 }
569 
570 TEST_F(MatchSelectPatternTest, NotNotUMinSwap) {
571   parseAssembly(
572       "define i8 @test(i8 %a, i8 %b) {\n"
573       "  %cmp = icmp ult i8 %a, %b\n"
574       "  %an = xor i8 %a, -1\n"
575       "  %bn = xor i8 %b, -1\n"
576       "  %A = select i1 %cmp, i8 %bn, i8 %an\n"
577       "  ret i8 %A\n"
578       "}\n");
579   expectPattern({SPF_UMIN, SPNB_NA, false});
580 }
581 
582 TEST_F(MatchSelectPatternTest, NotNotUMax) {
583   parseAssembly(
584       "define <2 x i8> @test(<2 x i8> %a, <2 x i8> %b) {\n"
585       "  %cmp = icmp ult <2 x i8> %a, %b\n"
586       "  %an = xor <2 x i8> %a, <i8 -1, i8-1>\n"
587       "  %bn = xor <2 x i8> %b, <i8 -1, i8-1>\n"
588       "  %A = select <2 x i1> %cmp, <2 x i8> %an, <2 x i8> %bn\n"
589       "  ret <2 x i8> %A\n"
590       "}\n");
591   expectPattern({SPF_UMAX, SPNB_NA, false});
592 }
593 
594 TEST_F(MatchSelectPatternTest, NotNotUMaxSwap) {
595   parseAssembly(
596       "define i8 @test(i8 %a, i8 %b) {\n"
597       "  %cmp = icmp ugt i8 %a, %b\n"
598       "  %an = xor i8 %a, -1\n"
599       "  %bn = xor i8 %b, -1\n"
600       "  %A = select i1 %cmp, i8 %bn, i8 %an\n"
601       "  ret i8 %A\n"
602       "}\n");
603   expectPattern({SPF_UMAX, SPNB_NA, false});
604 }
605 
606 TEST_F(MatchSelectPatternTest, NotNotEq) {
607   parseAssembly(
608       "define i8 @test(i8 %a, i8 %b) {\n"
609       "  %cmp = icmp eq i8 %a, %b\n"
610       "  %an = xor i8 %a, -1\n"
611       "  %bn = xor i8 %b, -1\n"
612       "  %A = select i1 %cmp, i8 %bn, i8 %an\n"
613       "  ret i8 %A\n"
614       "}\n");
615   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
616 }
617 
618 TEST_F(MatchSelectPatternTest, NotNotNe) {
619   parseAssembly(
620       "define i8 @test(i8 %a, i8 %b) {\n"
621       "  %cmp = icmp ne i8 %a, %b\n"
622       "  %an = xor i8 %a, -1\n"
623       "  %bn = xor i8 %b, -1\n"
624       "  %A = select i1 %cmp, i8 %bn, i8 %an\n"
625       "  ret i8 %A\n"
626       "}\n");
627   expectPattern({SPF_UNKNOWN, SPNB_NA, false});
628 }
629 
630 TEST(ValueTracking, GuaranteedToTransferExecutionToSuccessor) {
631   StringRef Assembly =
632       "declare void @nounwind_readonly(ptr) nounwind readonly "
633       "declare void @nounwind_argmemonly(ptr) nounwind argmemonly "
634       "declare void @nounwind_willreturn(ptr) nounwind willreturn "
635       "declare void @throws_but_readonly(ptr) readonly "
636       "declare void @throws_but_argmemonly(ptr) argmemonly "
637       "declare void @throws_but_willreturn(ptr) willreturn "
638       " "
639       "declare void @unknown(ptr) "
640       " "
641       "define void @f(ptr %p) { "
642       "  call void @nounwind_readonly(ptr %p) "
643       "  call void @nounwind_argmemonly(ptr %p) "
644       "  call void @nounwind_willreturn(ptr %p)"
645       "  call void @throws_but_readonly(ptr %p) "
646       "  call void @throws_but_argmemonly(ptr %p) "
647       "  call void @throws_but_willreturn(ptr %p) "
648       "  call void @unknown(ptr %p) nounwind readonly "
649       "  call void @unknown(ptr %p) nounwind argmemonly "
650       "  call void @unknown(ptr %p) nounwind willreturn "
651       "  call void @unknown(ptr %p) readonly "
652       "  call void @unknown(ptr %p) argmemonly "
653       "  call void @unknown(ptr %p) willreturn "
654       "  ret void "
655       "} ";
656 
657   LLVMContext Context;
658   SMDiagnostic Error;
659   auto M = parseAssemblyString(Assembly, Error, Context);
660   assert(M && "Bad assembly?");
661 
662   auto *F = M->getFunction("f");
663   assert(F && "Bad assembly?");
664 
665   auto &BB = F->getEntryBlock();
666   bool ExpectedAnswers[] = {
667       false, // call void @nounwind_readonly(ptr %p)
668       false, // call void @nounwind_argmemonly(ptr %p)
669       true,  // call void @nounwind_willreturn(ptr %p)
670       false, // call void @throws_but_readonly(ptr %p)
671       false, // call void @throws_but_argmemonly(ptr %p)
672       false, // call void @throws_but_willreturn(ptr %p)
673       false, // call void @unknown(ptr %p) nounwind readonly
674       false, // call void @unknown(ptr %p) nounwind argmemonly
675       true,  // call void @unknown(ptr %p) nounwind willreturn
676       false, // call void @unknown(ptr %p) readonly
677       false, // call void @unknown(ptr %p) argmemonly
678       false, // call void @unknown(ptr %p) willreturn
679       false, // ret void
680   };
681 
682   int Index = 0;
683   for (auto &I : BB) {
684     EXPECT_EQ(isGuaranteedToTransferExecutionToSuccessor(&I),
685               ExpectedAnswers[Index])
686         << "Incorrect answer at instruction " << Index << " = " << I;
687     Index++;
688   }
689 }
690 
691 TEST_F(ValueTrackingTest, ComputeNumSignBits_PR32045) {
692   parseAssembly(
693       "define i32 @test(i32 %a) {\n"
694       "  %A = ashr i32 %a, -1\n"
695       "  ret i32 %A\n"
696       "}\n");
697   EXPECT_EQ(ComputeNumSignBits(A, M->getDataLayout()), 32u);
698 }
699 
700 // No guarantees for canonical IR in this analysis, so this just bails out.
701 TEST_F(ValueTrackingTest, ComputeNumSignBits_Shuffle) {
702   parseAssembly(
703       "define <2 x i32> @test() {\n"
704       "  %A = shufflevector <2 x i32> undef, <2 x i32> undef, <2 x i32> <i32 0, i32 0>\n"
705       "  ret <2 x i32> %A\n"
706       "}\n");
707   EXPECT_EQ(ComputeNumSignBits(A, M->getDataLayout()), 1u);
708 }
709 
710 // No guarantees for canonical IR in this analysis, so a shuffle element that
711 // references an undef value means this can't return any extra information.
712 TEST_F(ValueTrackingTest, ComputeNumSignBits_Shuffle2) {
713   parseAssembly(
714       "define <2 x i32> @test(<2 x i1> %x) {\n"
715       "  %sext = sext <2 x i1> %x to <2 x i32>\n"
716       "  %A = shufflevector <2 x i32> %sext, <2 x i32> undef, <2 x i32> <i32 0, i32 2>\n"
717       "  ret <2 x i32> %A\n"
718       "}\n");
719   EXPECT_EQ(ComputeNumSignBits(A, M->getDataLayout()), 1u);
720 }
721 
722 TEST_F(ValueTrackingTest, impliesPoisonTest_Identity) {
723   parseAssembly("define void @test(i32 %x, i32 %y) {\n"
724                 "  %A = add i32 %x, %y\n"
725                 "  ret void\n"
726                 "}");
727   EXPECT_TRUE(impliesPoison(A, A));
728 }
729 
730 TEST_F(ValueTrackingTest, impliesPoisonTest_ICmp) {
731   parseAssembly("define void @test(i32 %x) {\n"
732                 "  %A2 = icmp eq i32 %x, 0\n"
733                 "  %A = icmp eq i32 %x, 1\n"
734                 "  ret void\n"
735                 "}");
736   EXPECT_TRUE(impliesPoison(A2, A));
737 }
738 
739 TEST_F(ValueTrackingTest, impliesPoisonTest_ICmpUnknown) {
740   parseAssembly("define void @test(i32 %x, i32 %y) {\n"
741                 "  %A2 = icmp eq i32 %x, %y\n"
742                 "  %A = icmp eq i32 %x, 1\n"
743                 "  ret void\n"
744                 "}");
745   EXPECT_FALSE(impliesPoison(A2, A));
746 }
747 
748 TEST_F(ValueTrackingTest, impliesPoisonTest_AddNswOkay) {
749   parseAssembly("define void @test(i32 %x) {\n"
750                 "  %A2 = add nsw i32 %x, 1\n"
751                 "  %A = add i32 %A2, 1\n"
752                 "  ret void\n"
753                 "}");
754   EXPECT_TRUE(impliesPoison(A2, A));
755 }
756 
757 TEST_F(ValueTrackingTest, impliesPoisonTest_AddNswOkay2) {
758   parseAssembly("define void @test(i32 %x) {\n"
759                 "  %A2 = add i32 %x, 1\n"
760                 "  %A = add nsw i32 %A2, 1\n"
761                 "  ret void\n"
762                 "}");
763   EXPECT_TRUE(impliesPoison(A2, A));
764 }
765 
766 TEST_F(ValueTrackingTest, impliesPoisonTest_AddNsw) {
767   parseAssembly("define void @test(i32 %x) {\n"
768                 "  %A2 = add nsw i32 %x, 1\n"
769                 "  %A = add i32 %x, 1\n"
770                 "  ret void\n"
771                 "}");
772   EXPECT_FALSE(impliesPoison(A2, A));
773 }
774 
775 TEST_F(ValueTrackingTest, impliesPoisonTest_Cmp) {
776   parseAssembly("define void @test(i32 %x, i32 %y, i1 %c) {\n"
777                 "  %A2 = icmp eq i32 %x, %y\n"
778                 "  %A0 = icmp ult i32 %x, %y\n"
779                 "  %A = or i1 %A0, %c\n"
780                 "  ret void\n"
781                 "}");
782   EXPECT_TRUE(impliesPoison(A2, A));
783 }
784 
785 TEST_F(ValueTrackingTest, impliesPoisonTest_FCmpFMF) {
786   parseAssembly("define void @test(float %x, float %y, i1 %c) {\n"
787                 "  %A2 = fcmp nnan oeq float %x, %y\n"
788                 "  %A0 = fcmp olt float %x, %y\n"
789                 "  %A = or i1 %A0, %c\n"
790                 "  ret void\n"
791                 "}");
792   EXPECT_FALSE(impliesPoison(A2, A));
793 }
794 
795 TEST_F(ValueTrackingTest, impliesPoisonTest_AddSubSameOps) {
796   parseAssembly("define void @test(i32 %x, i32 %y, i1 %c) {\n"
797                 "  %A2 = add i32 %x, %y\n"
798                 "  %A = sub i32 %x, %y\n"
799                 "  ret void\n"
800                 "}");
801   EXPECT_TRUE(impliesPoison(A2, A));
802 }
803 
804 TEST_F(ValueTrackingTest, impliesPoisonTest_MaskCmp) {
805   parseAssembly("define void @test(i32 %x, i32 %y, i1 %c) {\n"
806                 "  %M2 = and i32 %x, 7\n"
807                 "  %A2 = icmp eq i32 %M2, 1\n"
808                 "  %M = and i32 %x, 15\n"
809                 "  %A = icmp eq i32 %M, 3\n"
810                 "  ret void\n"
811                 "}");
812   EXPECT_TRUE(impliesPoison(A2, A));
813 }
814 
815 TEST_F(ValueTrackingTest, ComputeNumSignBits_Shuffle_Pointers) {
816   parseAssembly(
817       "define <2 x ptr> @test(<2 x ptr> %x) {\n"
818       "  %A = shufflevector <2 x ptr> zeroinitializer, <2 x ptr> undef, <2 x i32> zeroinitializer\n"
819       "  ret <2 x ptr> %A\n"
820       "}\n");
821   EXPECT_EQ(ComputeNumSignBits(A, M->getDataLayout()), 64u);
822 }
823 
824 TEST(ValueTracking, propagatesPoison) {
825   std::string AsmHead =
826       "declare i32 @g(i32)\n"
827       "declare {i32, i1} @llvm.sadd.with.overflow.i32(i32 %a, i32 %b)\n"
828       "declare {i32, i1} @llvm.ssub.with.overflow.i32(i32 %a, i32 %b)\n"
829       "declare {i32, i1} @llvm.smul.with.overflow.i32(i32 %a, i32 %b)\n"
830       "declare {i32, i1} @llvm.uadd.with.overflow.i32(i32 %a, i32 %b)\n"
831       "declare {i32, i1} @llvm.usub.with.overflow.i32(i32 %a, i32 %b)\n"
832       "declare {i32, i1} @llvm.umul.with.overflow.i32(i32 %a, i32 %b)\n"
833       "declare float @llvm.sqrt.f32(float)\n"
834       "declare float @llvm.powi.f32.i32(float, i32)\n"
835       "declare float @llvm.sin.f32(float)\n"
836       "declare float @llvm.cos.f32(float)\n"
837       "declare float @llvm.pow.f32(float, float)\n"
838       "declare float @llvm.exp.f32(float)\n"
839       "declare float @llvm.exp2.f32(float)\n"
840       "declare float @llvm.log.f32(float)\n"
841       "declare float @llvm.log10.f32(float)\n"
842       "declare float @llvm.log2.f32(float)\n"
843       "declare float @llvm.fma.f32(float, float, float)\n"
844       "declare float @llvm.fabs.f32(float)\n"
845       "declare float @llvm.minnum.f32(float, float)\n"
846       "declare float @llvm.maxnum.f32(float, float)\n"
847       "declare float @llvm.minimum.f32(float, float)\n"
848       "declare float @llvm.maximum.f32(float, float)\n"
849       "declare float @llvm.copysign.f32(float, float)\n"
850       "declare float @llvm.floor.f32(float)\n"
851       "declare float @llvm.ceil.f32(float)\n"
852       "declare float @llvm.trunc.f32(float)\n"
853       "declare float @llvm.rint.f32(float)\n"
854       "declare float @llvm.nearbyint.f32(float)\n"
855       "declare float @llvm.round.f32(float)\n"
856       "declare float @llvm.roundeven.f32(float)\n"
857       "declare i32 @llvm.lround.f32(float)\n"
858       "declare i64 @llvm.llround.f32(float)\n"
859       "declare i32 @llvm.lrint.f32(float)\n"
860       "declare i64 @llvm.llrint.f32(float)\n"
861       "declare float @llvm.fmuladd.f32(float, float, float)\n"
862       "define void @f(i32 %x, i32 %y, float %fx, float %fy, "
863       "i1 %cond, ptr %p) {\n";
864   std::string AsmTail = "  ret void\n}";
865   // (propagates poison?, IR instruction)
866   SmallVector<std::tuple<bool, std::string, unsigned>, 32> Data = {
867       {true, "add i32 %x, %y", 0},
868       {true, "add i32 %x, %y", 1},
869       {true, "add nsw nuw i32 %x, %y", 0},
870       {true, "add nsw nuw i32 %x, %y", 1},
871       {true, "ashr i32 %x, %y", 0},
872       {true, "ashr i32 %x, %y", 1},
873       {true, "lshr exact i32 %x, 31", 0},
874       {true, "lshr exact i32 %x, 31", 1},
875       {true, "fadd float %fx, %fy", 0},
876       {true, "fadd float %fx, %fy", 1},
877       {true, "fsub float %fx, %fy", 0},
878       {true, "fsub float %fx, %fy", 1},
879       {true, "fmul float %fx, %fy", 0},
880       {true, "fmul float %fx, %fy", 1},
881       {true, "fdiv float %fx, %fy", 0},
882       {true, "fdiv float %fx, %fy", 1},
883       {true, "frem float %fx, %fy", 0},
884       {true, "frem float %fx, %fy", 1},
885       {true, "fneg float %fx", 0},
886       {true, "fcmp oeq float %fx, %fy", 0},
887       {true, "fcmp oeq float %fx, %fy", 1},
888       {true, "icmp eq i32 %x, %y", 0},
889       {true, "icmp eq i32 %x, %y", 1},
890       {true, "getelementptr i8, ptr %p, i32 %x", 0},
891       {true, "getelementptr i8, ptr %p, i32 %x", 1},
892       {true, "getelementptr inbounds i8, ptr %p, i32 %x", 0},
893       {true, "getelementptr inbounds i8, ptr %p, i32 %x", 1},
894       {true, "bitcast float %fx to i32", 0},
895       {true, "select i1 %cond, i32 %x, i32 %y", 0},
896       {false, "select i1 %cond, i32 %x, i32 %y", 1},
897       {false, "select i1 %cond, i32 %x, i32 %y", 2},
898       {false, "freeze i32 %x", 0},
899       {true, "udiv i32 %x, %y", 0},
900       {true, "udiv i32 %x, %y", 1},
901       {true, "urem i32 %x, %y", 0},
902       {true, "urem i32 %x, %y", 1},
903       {true, "sdiv exact i32 %x, %y", 0},
904       {true, "sdiv exact i32 %x, %y", 1},
905       {true, "srem i32 %x, %y", 0},
906       {true, "srem i32 %x, %y", 1},
907       {false, "call i32 @g(i32 %x)", 0},
908       {false, "call i32 @g(i32 %x)", 1},
909       {true, "call {i32, i1} @llvm.sadd.with.overflow.i32(i32 %x, i32 %y)", 0},
910       {true, "call {i32, i1} @llvm.ssub.with.overflow.i32(i32 %x, i32 %y)", 0},
911       {true, "call {i32, i1} @llvm.smul.with.overflow.i32(i32 %x, i32 %y)", 0},
912       {true, "call {i32, i1} @llvm.uadd.with.overflow.i32(i32 %x, i32 %y)", 0},
913       {true, "call {i32, i1} @llvm.usub.with.overflow.i32(i32 %x, i32 %y)", 0},
914       {true, "call {i32, i1} @llvm.umul.with.overflow.i32(i32 %x, i32 %y)", 0},
915       {false, "call float @llvm.sqrt.f32(float %fx)", 0},
916       {false, "call float @llvm.powi.f32.i32(float %fx, i32 %x)", 0},
917       {false, "call float @llvm.sin.f32(float %fx)", 0},
918       {false, "call float @llvm.cos.f32(float %fx)", 0},
919       {false, "call float @llvm.pow.f32(float %fx, float %fy)", 0},
920       {false, "call float @llvm.exp.f32(float %fx)", 0},
921       {false, "call float @llvm.exp2.f32(float %fx)", 0},
922       {false, "call float @llvm.log.f32(float %fx)", 0},
923       {false, "call float @llvm.log10.f32(float %fx)", 0},
924       {false, "call float @llvm.log2.f32(float %fx)", 0},
925       {false, "call float @llvm.fma.f32(float %fx, float %fx, float %fy)", 0},
926       {false, "call float @llvm.fabs.f32(float %fx)", 0},
927       {false, "call float @llvm.minnum.f32(float %fx, float %fy)", 0},
928       {false, "call float @llvm.maxnum.f32(float %fx, float %fy)", 0},
929       {false, "call float @llvm.minimum.f32(float %fx, float %fy)", 0},
930       {false, "call float @llvm.maximum.f32(float %fx, float %fy)", 0},
931       {false, "call float @llvm.copysign.f32(float %fx, float %fy)", 0},
932       {false, "call float @llvm.floor.f32(float %fx)", 0},
933       {false, "call float @llvm.ceil.f32(float %fx)", 0},
934       {false, "call float @llvm.trunc.f32(float %fx)", 0},
935       {false, "call float @llvm.rint.f32(float %fx)", 0},
936       {false, "call float @llvm.nearbyint.f32(float %fx)", 0},
937       {false, "call float @llvm.round.f32(float %fx)", 0},
938       {false, "call float @llvm.roundeven.f32(float %fx)", 0},
939       {false, "call i32 @llvm.lround.f32(float %fx)", 0},
940       {false, "call i64 @llvm.llround.f32(float %fx)", 0},
941       {false, "call i32 @llvm.lrint.f32(float %fx)", 0},
942       {false, "call i64 @llvm.llrint.f32(float %fx)", 0},
943       {false, "call float @llvm.fmuladd.f32(float %fx, float %fx, float %fy)",
944        0}};
945 
946   std::string AssemblyStr = AsmHead;
947   for (auto &Itm : Data)
948     AssemblyStr += std::get<1>(Itm) + "\n";
949   AssemblyStr += AsmTail;
950 
951   LLVMContext Context;
952   SMDiagnostic Error;
953   auto M = parseAssemblyString(AssemblyStr, Error, Context);
954   assert(M && "Bad assembly?");
955 
956   auto *F = M->getFunction("f");
957   assert(F && "Bad assembly?");
958 
959   auto &BB = F->getEntryBlock();
960 
961   int Index = 0;
962   for (auto &I : BB) {
963     if (isa<ReturnInst>(&I))
964       break;
965     bool ExpectedVal = std::get<0>(Data[Index]);
966     unsigned OpIdx = std::get<2>(Data[Index]);
967     EXPECT_EQ(propagatesPoison(I.getOperandUse(OpIdx)), ExpectedVal)
968         << "Incorrect answer at instruction " << Index << " = " << I;
969     Index++;
970   }
971 }
972 
973 TEST_F(ValueTrackingTest, programUndefinedIfPoison) {
974   parseAssembly("declare i32 @any_num()"
975                 "define void @test(i32 %mask) {\n"
976                 "  %A = call i32 @any_num()\n"
977                 "  %B = or i32 %A, %mask\n"
978                 "  udiv i32 1, %B"
979                 "  ret void\n"
980                 "}\n");
981   // If %A was poison, udiv raises UB regardless of %mask's value
982   EXPECT_EQ(programUndefinedIfPoison(A), true);
983 }
984 
985 TEST_F(ValueTrackingTest, programUndefinedIfPoisonSelect) {
986   parseAssembly("declare i32 @any_num()"
987                 "define void @test(i1 %Cond) {\n"
988                 "  %A = call i32 @any_num()\n"
989                 "  %B = add i32 %A, 1\n"
990                 "  %C = select i1 %Cond, i32 %A, i32 %B\n"
991                 "  udiv i32 1, %C"
992                 "  ret void\n"
993                 "}\n");
994   // If A is poison, B is also poison, and therefore C is poison regardless of
995   // the value of %Cond.
996   EXPECT_EQ(programUndefinedIfPoison(A), true);
997 }
998 
999 TEST_F(ValueTrackingTest, programUndefinedIfUndefOrPoison) {
1000   parseAssembly("declare i32 @any_num()"
1001                 "define void @test(i32 %mask) {\n"
1002                 "  %A = call i32 @any_num()\n"
1003                 "  %B = or i32 %A, %mask\n"
1004                 "  udiv i32 1, %B"
1005                 "  ret void\n"
1006                 "}\n");
1007   // If %A was undef and %mask was 1, udiv does not raise UB
1008   EXPECT_EQ(programUndefinedIfUndefOrPoison(A), false);
1009 }
1010 
1011 TEST_F(ValueTrackingTest, isGuaranteedNotToBePoison_exploitBranchCond) {
1012   parseAssembly("declare i1 @any_bool()"
1013                 "define void @test(i1 %y) {\n"
1014                 "  %A = call i1 @any_bool()\n"
1015                 "  %cond = and i1 %A, %y\n"
1016                 "  br i1 %cond, label %BB1, label %BB2\n"
1017                 "BB1:\n"
1018                 "  ret void\n"
1019                 "BB2:\n"
1020                 "  ret void\n"
1021                 "}\n");
1022   DominatorTree DT(*F);
1023   for (auto &BB : *F) {
1024     if (&BB == &F->getEntryBlock())
1025       continue;
1026 
1027     EXPECT_EQ(isGuaranteedNotToBePoison(A, nullptr, BB.getTerminator(), &DT),
1028               true)
1029         << "isGuaranteedNotToBePoison does not hold at " << *BB.getTerminator();
1030   }
1031 }
1032 
1033 TEST_F(ValueTrackingTest, isGuaranteedNotToBePoison_phi) {
1034   parseAssembly("declare i32 @any_i32(i32)"
1035                 "define void @test() {\n"
1036                 "ENTRY:\n"
1037                 "  br label %LOOP\n"
1038                 "LOOP:\n"
1039                 "  %A = phi i32 [0, %ENTRY], [%A.next, %NEXT]\n"
1040                 "  %A.next = call i32 @any_i32(i32 %A)\n"
1041                 "  %cond = icmp eq i32 %A.next, 0\n"
1042                 "  br i1 %cond, label %NEXT, label %EXIT\n"
1043                 "NEXT:\n"
1044                 "  br label %LOOP\n"
1045                 "EXIT:\n"
1046                 "  ret void\n"
1047                 "}\n");
1048   DominatorTree DT(*F);
1049   for (auto &BB : *F) {
1050     if (BB.getName() == "LOOP") {
1051       EXPECT_EQ(isGuaranteedNotToBePoison(A, nullptr, A, &DT), true)
1052           << "isGuaranteedNotToBePoison does not hold";
1053     }
1054   }
1055 }
1056 
1057 TEST_F(ValueTrackingTest, isGuaranteedNotToBeUndefOrPoison) {
1058   parseAssembly("declare void @f(i32 noundef)"
1059                 "define void @test(i32 %x) {\n"
1060                 "  %A = bitcast i32 %x to i32\n"
1061                 "  call void @f(i32 noundef %x)\n"
1062                 "  ret void\n"
1063                 "}\n");
1064   EXPECT_EQ(isGuaranteedNotToBeUndefOrPoison(A), true);
1065   EXPECT_EQ(isGuaranteedNotToBeUndefOrPoison(UndefValue::get(IntegerType::get(Context, 8))), false);
1066   EXPECT_EQ(isGuaranteedNotToBeUndefOrPoison(PoisonValue::get(IntegerType::get(Context, 8))), false);
1067   EXPECT_EQ(isGuaranteedNotToBePoison(UndefValue::get(IntegerType::get(Context, 8))), true);
1068   EXPECT_EQ(isGuaranteedNotToBePoison(PoisonValue::get(IntegerType::get(Context, 8))), false);
1069 
1070   Type *Int32Ty = Type::getInt32Ty(Context);
1071   Constant *CU = UndefValue::get(Int32Ty);
1072   Constant *CP = PoisonValue::get(Int32Ty);
1073   Constant *C1 = ConstantInt::get(Int32Ty, 1);
1074   Constant *C2 = ConstantInt::get(Int32Ty, 2);
1075 
1076   {
1077     Constant *V1 = ConstantVector::get({C1, C2});
1078     EXPECT_TRUE(isGuaranteedNotToBeUndefOrPoison(V1));
1079     EXPECT_TRUE(isGuaranteedNotToBePoison(V1));
1080   }
1081 
1082   {
1083     Constant *V2 = ConstantVector::get({C1, CU});
1084     EXPECT_FALSE(isGuaranteedNotToBeUndefOrPoison(V2));
1085     EXPECT_TRUE(isGuaranteedNotToBePoison(V2));
1086   }
1087 
1088   {
1089     Constant *V3 = ConstantVector::get({C1, CP});
1090     EXPECT_FALSE(isGuaranteedNotToBeUndefOrPoison(V3));
1091     EXPECT_FALSE(isGuaranteedNotToBePoison(V3));
1092   }
1093 }
1094 
1095 TEST_F(ValueTrackingTest, isGuaranteedNotToBeUndefOrPoison_assume) {
1096   parseAssembly("declare i1 @f_i1()\n"
1097                 "declare i32 @f_i32()\n"
1098                 "declare void @llvm.assume(i1)\n"
1099                 "define void @test() {\n"
1100                 "  %A = call i32 @f_i32()\n"
1101                 "  %cond = call i1 @f_i1()\n"
1102                 "  %CxtI = add i32 0, 0\n"
1103                 "  br i1 %cond, label %BB1, label %EXIT\n"
1104                 "BB1:\n"
1105                 "  %CxtI2 = add i32 0, 0\n"
1106                 "  %cond2 = call i1 @f_i1()\n"
1107                 "  call void @llvm.assume(i1 true) [ \"noundef\"(i32 %A) ]\n"
1108                 "  br i1 %cond2, label %BB2, label %EXIT\n"
1109                 "BB2:\n"
1110                 "  %CxtI3 = add i32 0, 0\n"
1111                 "  ret void\n"
1112                 "EXIT:\n"
1113                 "  ret void\n"
1114                 "}");
1115   AssumptionCache AC(*F);
1116   DominatorTree DT(*F);
1117   EXPECT_FALSE(isGuaranteedNotToBeUndefOrPoison(A, &AC, CxtI, &DT));
1118   EXPECT_FALSE(isGuaranteedNotToBeUndefOrPoison(A, &AC, CxtI2, &DT));
1119   EXPECT_TRUE(isGuaranteedNotToBeUndefOrPoison(A, &AC, CxtI3, &DT));
1120 }
1121 
1122 TEST(ValueTracking, canCreatePoisonOrUndef) {
1123   std::string AsmHead =
1124       "@s = external dso_local global i32, align 1\n"
1125       "declare i32 @g(i32)\n"
1126       "declare {i32, i1} @llvm.sadd.with.overflow.i32(i32 %a, i32 %b)\n"
1127       "declare {i32, i1} @llvm.ssub.with.overflow.i32(i32 %a, i32 %b)\n"
1128       "declare {i32, i1} @llvm.smul.with.overflow.i32(i32 %a, i32 %b)\n"
1129       "declare {i32, i1} @llvm.uadd.with.overflow.i32(i32 %a, i32 %b)\n"
1130       "declare {i32, i1} @llvm.usub.with.overflow.i32(i32 %a, i32 %b)\n"
1131       "declare {i32, i1} @llvm.umul.with.overflow.i32(i32 %a, i32 %b)\n"
1132       "define void @f(i32 %x, i32 %y, float %fx, float %fy, i1 %cond, "
1133       "<4 x i32> %vx, <4 x i32> %vx2, <vscale x 4 x i32> %svx, ptr %p) {\n";
1134   std::string AsmTail = "  ret void\n}";
1135   // (can create poison?, can create undef?, IR instruction)
1136   SmallVector<std::pair<std::pair<bool, bool>, std::string>, 32> Data = {
1137       {{false, false}, "add i32 %x, %y"},
1138       {{true, false}, "add nsw nuw i32 %x, %y"},
1139       {{true, false}, "shl i32 %x, %y"},
1140       {{true, false}, "shl <4 x i32> %vx, %vx2"},
1141       {{true, false}, "shl nsw i32 %x, %y"},
1142       {{true, false}, "shl nsw <4 x i32> %vx, <i32 0, i32 1, i32 2, i32 3>"},
1143       {{false, false}, "shl i32 %x, 31"},
1144       {{true, false}, "shl i32 %x, 32"},
1145       {{false, false}, "shl <4 x i32> %vx, <i32 0, i32 1, i32 2, i32 3>"},
1146       {{true, false}, "shl <4 x i32> %vx, <i32 0, i32 1, i32 2, i32 32>"},
1147       {{true, false}, "ashr i32 %x, %y"},
1148       {{true, false}, "ashr exact i32 %x, %y"},
1149       {{false, false}, "ashr i32 %x, 31"},
1150       {{true, false}, "ashr exact i32 %x, 31"},
1151       {{false, false}, "ashr <4 x i32> %vx, <i32 0, i32 1, i32 2, i32 3>"},
1152       {{true, false}, "ashr <4 x i32> %vx, <i32 0, i32 1, i32 2, i32 32>"},
1153       {{true, false}, "ashr exact <4 x i32> %vx, <i32 0, i32 1, i32 2, i32 3>"},
1154       {{true, false}, "lshr i32 %x, %y"},
1155       {{true, false}, "lshr exact i32 %x, 31"},
1156       {{false, false}, "udiv i32 %x, %y"},
1157       {{true, false}, "udiv exact i32 %x, %y"},
1158       {{false, false}, "getelementptr i8, ptr %p, i32 %x"},
1159       {{true, false}, "getelementptr inbounds i8, ptr %p, i32 %x"},
1160       {{true, false}, "fneg nnan float %fx"},
1161       {{false, false}, "fneg float %fx"},
1162       {{false, false}, "fadd float %fx, %fy"},
1163       {{true, false}, "fadd nnan float %fx, %fy"},
1164       {{false, false}, "urem i32 %x, %y"},
1165       {{true, false}, "fptoui float %fx to i32"},
1166       {{true, false}, "fptosi float %fx to i32"},
1167       {{false, false}, "bitcast float %fx to i32"},
1168       {{false, false}, "select i1 %cond, i32 %x, i32 %y"},
1169       {{true, false}, "select nnan i1 %cond, float %fx, float %fy"},
1170       {{true, false}, "extractelement <4 x i32> %vx, i32 %x"},
1171       {{false, false}, "extractelement <4 x i32> %vx, i32 3"},
1172       {{true, false}, "extractelement <vscale x 4 x i32> %svx, i32 4"},
1173       {{true, false}, "insertelement <4 x i32> %vx, i32 %x, i32 %y"},
1174       {{false, false}, "insertelement <4 x i32> %vx, i32 %x, i32 3"},
1175       {{true, false}, "insertelement <vscale x 4 x i32> %svx, i32 %x, i32 4"},
1176       {{false, false}, "freeze i32 %x"},
1177       {{false, false},
1178        "shufflevector <4 x i32> %vx, <4 x i32> %vx2, "
1179        "<4 x i32> <i32 0, i32 1, i32 2, i32 3>"},
1180       {{false, true},
1181        "shufflevector <4 x i32> %vx, <4 x i32> %vx2, "
1182        "<4 x i32> <i32 0, i32 1, i32 2, i32 undef>"},
1183       {{false, true},
1184        "shufflevector <vscale x 4 x i32> %svx, "
1185        "<vscale x 4 x i32> %svx, <vscale x 4 x i32> undef"},
1186       {{true, false}, "call i32 @g(i32 %x)"},
1187       {{false, false}, "call noundef i32 @g(i32 %x)"},
1188       {{true, false}, "fcmp nnan oeq float %fx, %fy"},
1189       {{false, false}, "fcmp oeq float %fx, %fy"},
1190       {{true, false}, "ashr i32 %x, ptrtoint (ptr @s to i32)"},
1191       {{false, false},
1192        "call {i32, i1} @llvm.sadd.with.overflow.i32(i32 %x, i32 %y)"},
1193       {{false, false},
1194        "call {i32, i1} @llvm.ssub.with.overflow.i32(i32 %x, i32 %y)"},
1195       {{false, false},
1196        "call {i32, i1} @llvm.smul.with.overflow.i32(i32 %x, i32 %y)"},
1197       {{false, false},
1198        "call {i32, i1} @llvm.uadd.with.overflow.i32(i32 %x, i32 %y)"},
1199       {{false, false},
1200        "call {i32, i1} @llvm.usub.with.overflow.i32(i32 %x, i32 %y)"},
1201       {{false, false},
1202        "call {i32, i1} @llvm.umul.with.overflow.i32(i32 %x, i32 %y)"}};
1203 
1204   std::string AssemblyStr = AsmHead;
1205   for (auto &Itm : Data)
1206     AssemblyStr += Itm.second + "\n";
1207   AssemblyStr += AsmTail;
1208 
1209   LLVMContext Context;
1210   SMDiagnostic Error;
1211   auto M = parseAssemblyString(AssemblyStr, Error, Context);
1212   assert(M && "Bad assembly?");
1213 
1214   auto *F = M->getFunction("f");
1215   assert(F && "Bad assembly?");
1216 
1217   auto &BB = F->getEntryBlock();
1218 
1219   int Index = 0;
1220   for (auto &I : BB) {
1221     if (isa<ReturnInst>(&I))
1222       break;
1223     bool Poison = Data[Index].first.first;
1224     bool Undef = Data[Index].first.second;
1225     EXPECT_EQ(canCreatePoison(cast<Operator>(&I)), Poison)
1226         << "Incorrect answer of canCreatePoison at instruction " << Index
1227         << " = " << I;
1228     EXPECT_EQ(canCreateUndefOrPoison(cast<Operator>(&I)), Undef || Poison)
1229         << "Incorrect answer of canCreateUndef at instruction " << Index
1230         << " = " << I;
1231     Index++;
1232   }
1233 }
1234 
1235 TEST_F(ValueTrackingTest, computePtrAlignment) {
1236   parseAssembly("declare i1 @f_i1()\n"
1237                 "declare ptr @f_i8p()\n"
1238                 "declare void @llvm.assume(i1)\n"
1239                 "define void @test() {\n"
1240                 "  %A = call ptr @f_i8p()\n"
1241                 "  %cond = call i1 @f_i1()\n"
1242                 "  %CxtI = add i32 0, 0\n"
1243                 "  br i1 %cond, label %BB1, label %EXIT\n"
1244                 "BB1:\n"
1245                 "  %CxtI2 = add i32 0, 0\n"
1246                 "  %cond2 = call i1 @f_i1()\n"
1247                 "  call void @llvm.assume(i1 true) [ \"align\"(ptr %A, i64 16) ]\n"
1248                 "  br i1 %cond2, label %BB2, label %EXIT\n"
1249                 "BB2:\n"
1250                 "  %CxtI3 = add i32 0, 0\n"
1251                 "  ret void\n"
1252                 "EXIT:\n"
1253                 "  ret void\n"
1254                 "}");
1255   AssumptionCache AC(*F);
1256   DominatorTree DT(*F);
1257   const DataLayout &DL = M->getDataLayout();
1258   EXPECT_EQ(getKnownAlignment(A, DL, CxtI, &AC, &DT), Align(1));
1259   EXPECT_EQ(getKnownAlignment(A, DL, CxtI2, &AC, &DT), Align(1));
1260   EXPECT_EQ(getKnownAlignment(A, DL, CxtI3, &AC, &DT), Align(16));
1261 }
1262 
1263 TEST_F(ComputeKnownBitsTest, ComputeKnownBits) {
1264   parseAssembly(
1265       "define i32 @test(i32 %a, i32 %b) {\n"
1266       "  %ash = mul i32 %a, 8\n"
1267       "  %aad = add i32 %ash, 7\n"
1268       "  %aan = and i32 %aad, 4095\n"
1269       "  %bsh = shl i32 %b, 4\n"
1270       "  %bad = or i32 %bsh, 6\n"
1271       "  %ban = and i32 %bad, 4095\n"
1272       "  %A = mul i32 %aan, %ban\n"
1273       "  ret i32 %A\n"
1274       "}\n");
1275   expectKnownBits(/*zero*/ 4278190085u, /*one*/ 10u);
1276 }
1277 
1278 TEST_F(ComputeKnownBitsTest, ComputeKnownMulBits) {
1279   parseAssembly(
1280       "define i32 @test(i32 %a, i32 %b) {\n"
1281       "  %aa = shl i32 %a, 5\n"
1282       "  %bb = shl i32 %b, 5\n"
1283       "  %aaa = or i32 %aa, 24\n"
1284       "  %bbb = or i32 %bb, 28\n"
1285       "  %A = mul i32 %aaa, %bbb\n"
1286       "  ret i32 %A\n"
1287       "}\n");
1288   expectKnownBits(/*zero*/ 95u, /*one*/ 32u);
1289 }
1290 
1291 TEST_F(ComputeKnownFPClassTest, SelectPos0) {
1292   parseAssembly(
1293       "define float @test(i1 %cond) {\n"
1294       "  %A = select i1 %cond, float 0.0, float 0.0"
1295       "  ret float %A\n"
1296       "}\n");
1297   expectKnownFPClass(fcPosZero, false);
1298 }
1299 
1300 TEST_F(ComputeKnownFPClassTest, SelectNeg0) {
1301   parseAssembly(
1302       "define float @test(i1 %cond) {\n"
1303       "  %A = select i1 %cond, float -0.0, float -0.0"
1304       "  ret float %A\n"
1305       "}\n");
1306   expectKnownFPClass(fcNegZero, true);
1307 }
1308 
1309 TEST_F(ComputeKnownFPClassTest, SelectPosOrNeg0) {
1310   parseAssembly(
1311       "define float @test(i1 %cond) {\n"
1312       "  %A = select i1 %cond, float 0.0, float -0.0"
1313       "  ret float %A\n"
1314       "}\n");
1315   expectKnownFPClass(fcZero, std::nullopt);
1316 }
1317 
1318 TEST_F(ComputeKnownFPClassTest, SelectPosInf) {
1319   parseAssembly(
1320       "define float @test(i1 %cond) {\n"
1321       "  %A = select i1 %cond, float 0x7FF0000000000000, float 0x7FF0000000000000"
1322       "  ret float %A\n"
1323       "}\n");
1324   expectKnownFPClass(fcPosInf, false);
1325 }
1326 
1327 TEST_F(ComputeKnownFPClassTest, SelectNegInf) {
1328   parseAssembly(
1329       "define float @test(i1 %cond) {\n"
1330       "  %A = select i1 %cond, float 0xFFF0000000000000, float 0xFFF0000000000000"
1331       "  ret float %A\n"
1332       "}\n");
1333   expectKnownFPClass(fcNegInf, true);
1334 }
1335 
1336 TEST_F(ComputeKnownFPClassTest, SelectPosOrNegInf) {
1337   parseAssembly(
1338       "define float @test(i1 %cond) {\n"
1339       "  %A = select i1 %cond, float 0x7FF0000000000000, float 0xFFF0000000000000"
1340       "  ret float %A\n"
1341       "}\n");
1342   expectKnownFPClass(fcInf, std::nullopt);
1343 }
1344 
1345 TEST_F(ComputeKnownFPClassTest, SelectNNaN) {
1346   parseAssembly(
1347       "define float @test(i1 %cond, float %arg0, float %arg1) {\n"
1348       "  %A = select nnan i1 %cond, float %arg0, float %arg1"
1349       "  ret float %A\n"
1350       "}\n");
1351   expectKnownFPClass(~fcNan, std::nullopt);
1352 }
1353 
1354 TEST_F(ComputeKnownFPClassTest, SelectNInf) {
1355   parseAssembly(
1356       "define float @test(i1 %cond, float %arg0, float %arg1) {\n"
1357       "  %A = select ninf i1 %cond, float %arg0, float %arg1"
1358       "  ret float %A\n"
1359       "}\n");
1360   expectKnownFPClass(~fcInf, std::nullopt);
1361 }
1362 
1363 TEST_F(ComputeKnownFPClassTest, SelectNNaNNInf) {
1364   parseAssembly(
1365       "define float @test(i1 %cond, float %arg0, float %arg1) {\n"
1366       "  %A = select nnan ninf i1 %cond, float %arg0, float %arg1"
1367       "  ret float %A\n"
1368       "}\n");
1369   expectKnownFPClass(~(fcNan | fcInf), std::nullopt);
1370 }
1371 
1372 TEST_F(ComputeKnownFPClassTest, SelectNoFPClassArgUnionAll) {
1373   parseAssembly(
1374       "define float @test(i1 %cond, float nofpclass(snan ninf nsub pzero pnorm) %arg0, float nofpclass(qnan nnorm nzero psub pinf) %arg1) {\n"
1375       "  %A = select i1 %cond, float %arg0, float %arg1"
1376       "  ret float %A\n"
1377       "}\n");
1378   expectKnownFPClass(fcAllFlags, std::nullopt);
1379 }
1380 
1381 TEST_F(ComputeKnownFPClassTest, SelectNoFPClassArgNoNan) {
1382   parseAssembly(
1383       "define float @test(i1 %cond, float nofpclass(nan) %arg0, float nofpclass(nan) %arg1) {\n"
1384       "  %A = select i1 %cond, float %arg0, float %arg1"
1385       "  ret float %A\n"
1386       "}\n");
1387   expectKnownFPClass(~fcNan, std::nullopt);
1388 }
1389 
1390 TEST_F(ComputeKnownFPClassTest, SelectNoFPClassArgNoPInf) {
1391   parseAssembly(
1392       "define float @test(i1 %cond, float nofpclass(inf) %arg0, float nofpclass(pinf) %arg1) {\n"
1393       "  %A = select i1 %cond, float %arg0, float %arg1"
1394       "  ret float %A\n"
1395       "}\n");
1396   expectKnownFPClass(~fcPosInf, std::nullopt);
1397 }
1398 
1399 TEST_F(ComputeKnownFPClassTest, SelectNoFPClassArgNoNInf) {
1400   parseAssembly(
1401       "define float @test(i1 %cond, float nofpclass(ninf) %arg0, float nofpclass(inf) %arg1) {\n"
1402       "  %A = select i1 %cond, float %arg0, float %arg1"
1403       "  ret float %A\n"
1404       "}\n");
1405   expectKnownFPClass(~fcNegInf, std::nullopt);
1406 }
1407 
1408 TEST_F(ComputeKnownFPClassTest, SelectNoFPClassCallSiteNoNan) {
1409   parseAssembly(
1410       "declare float @func()\n"
1411       "define float @test() {\n"
1412       "  %A = call nofpclass(nan) float @func()\n"
1413       "  ret float %A\n"
1414       "}\n");
1415   expectKnownFPClass(~fcNan, std::nullopt);
1416 }
1417 
1418 TEST_F(ComputeKnownFPClassTest, SelectNoFPClassCallSiteNoZeros) {
1419   parseAssembly(
1420       "declare float @func()\n"
1421       "define float @test() {\n"
1422       "  %A = call nofpclass(zero) float @func()\n"
1423       "  ret float %A\n"
1424       "}\n");
1425   expectKnownFPClass(~fcZero, std::nullopt);
1426 }
1427 
1428 TEST_F(ComputeKnownFPClassTest, SelectNoFPClassDeclarationNoNan) {
1429   parseAssembly(
1430       "declare nofpclass(nan) float @no_nans()\n"
1431       "define float @test() {\n"
1432       "  %A = call float @no_nans()\n"
1433       "  ret float %A\n"
1434       "}\n");
1435   expectKnownFPClass(~fcNan, std::nullopt);
1436 }
1437 
1438 // Check nofpclass + ninf works on a callsite
1439 TEST_F(ComputeKnownFPClassTest, SelectNoFPClassCallSiteNoZerosNInfFlags) {
1440   parseAssembly(
1441       "declare float @func()\n"
1442       "define float @test() {\n"
1443       "  %A = call ninf nofpclass(zero) float @func()\n"
1444       "  ret float %A\n"
1445       "}\n");
1446   expectKnownFPClass(~(fcZero | fcInf), std::nullopt);
1447 }
1448 
1449 TEST_F(ComputeKnownFPClassTest, FNegNInf) {
1450   parseAssembly(
1451       "define float @test(float %arg) {\n"
1452       "  %A = fneg ninf float %arg"
1453       "  ret float %A\n"
1454       "}\n");
1455   expectKnownFPClass(~fcInf, std::nullopt);
1456 }
1457 
1458 TEST_F(ComputeKnownFPClassTest, FabsUnknown) {
1459   parseAssembly(
1460       "declare float @llvm.fabs.f32(float)"
1461       "define float @test(float %arg) {\n"
1462       "  %A = call float @llvm.fabs.f32(float %arg)"
1463       "  ret float %A\n"
1464       "}\n");
1465   expectKnownFPClass(fcPositive | fcNan, false);
1466 }
1467 
1468 TEST_F(ComputeKnownFPClassTest, FNegFabsUnknown) {
1469   parseAssembly(
1470       "declare float @llvm.fabs.f32(float)"
1471       "define float @test(float %arg) {\n"
1472       "  %fabs = call float @llvm.fabs.f32(float %arg)"
1473       "  %A = fneg float %fabs"
1474       "  ret float %A\n"
1475       "}\n");
1476   expectKnownFPClass(fcNegative | fcNan, true);
1477 }
1478 
1479 TEST_F(ComputeKnownFPClassTest, NegFabsNInf) {
1480   parseAssembly(
1481       "declare float @llvm.fabs.f32(float)"
1482       "define float @test(float %arg) {\n"
1483       "  %fabs = call ninf float @llvm.fabs.f32(float %arg)"
1484       "  %A = fneg float %fabs"
1485       "  ret float %A\n"
1486       "}\n");
1487   expectKnownFPClass((fcNegative & ~fcNegInf) | fcNan, true);
1488 }
1489 
1490 TEST_F(ComputeKnownFPClassTest, FNegFabsNNaN) {
1491   parseAssembly(
1492       "declare float @llvm.fabs.f32(float)"
1493       "define float @test(float %arg) {\n"
1494       "  %fabs = call nnan float @llvm.fabs.f32(float %arg)"
1495       "  %A = fneg float %fabs"
1496       "  ret float %A\n"
1497       "}\n");
1498   expectKnownFPClass(fcNegative, true);
1499 }
1500 
1501 TEST_F(ComputeKnownFPClassTest, CopySignNNanSrc0) {
1502   parseAssembly(
1503       "declare float @llvm.fabs.f32(float)\n"
1504       "declare float @llvm.copysign.f32(float, float)\n"
1505       "define float @test(float %arg0, float %arg1) {\n"
1506       "  %fabs = call nnan float @llvm.fabs.f32(float %arg0)"
1507       "  %A = call float @llvm.copysign.f32(float %fabs, float %arg1)"
1508       "  ret float %A\n"
1509       "}\n");
1510   expectKnownFPClass(~fcNan, std::nullopt);
1511 }
1512 
1513 TEST_F(ComputeKnownFPClassTest, CopySignNInfSrc0_NegSign) {
1514   parseAssembly(
1515       "declare float @llvm.log.f32(float)\n"
1516       "declare float @llvm.copysign.f32(float, float)\n"
1517       "define float @test(float %arg0, float %arg1) {\n"
1518       "  %ninf = call ninf float @llvm.log.f32(float %arg0)"
1519       "  %A = call float @llvm.copysign.f32(float %ninf, float -1.0)"
1520       "  ret float %A\n"
1521       "}\n");
1522   expectKnownFPClass(fcNegFinite | fcNan, true);
1523 }
1524 
1525 TEST_F(ComputeKnownFPClassTest, CopySignNInfSrc0_PosSign) {
1526   parseAssembly(
1527       "declare float @llvm.sqrt.f32(float)\n"
1528       "declare float @llvm.copysign.f32(float, float)\n"
1529       "define float @test(float %arg0, float %arg1) {\n"
1530       "  %ninf = call ninf float @llvm.sqrt.f32(float %arg0)"
1531       "  %A = call float @llvm.copysign.f32(float %ninf, float 1.0)"
1532       "  ret float %A\n"
1533       "}\n");
1534   expectKnownFPClass(fcPosFinite | fcNan, false);
1535 }
1536 
1537 TEST_F(ComputeKnownFPClassTest, UIToFP) {
1538   parseAssembly(
1539       "define float @test(i32 %arg0, i16 %arg1) {\n"
1540       "  %A = uitofp i32 %arg0 to float"
1541       "  %A2 = uitofp i16 %arg1 to half"
1542       "  ret float %A\n"
1543       "}\n");
1544   expectKnownFPClass(fcPosFinite & ~fcSubnormal, false, A);
1545   expectKnownFPClass(fcPositive & ~fcSubnormal, false, A2);
1546 }
1547 
1548 TEST_F(ComputeKnownFPClassTest, SIToFP) {
1549   parseAssembly(
1550       "define float @test(i32 %arg0, i16 %arg1, i17 %arg2) {\n"
1551       "  %A = sitofp i32 %arg0 to float"
1552       "  %A2 = sitofp i16 %arg1 to half"
1553       "  %A3 = sitofp i17 %arg2 to half"
1554       "  ret float %A\n"
1555       "}\n");
1556   expectKnownFPClass(fcFinite & ~fcNegZero & ~fcSubnormal, std::nullopt, A);
1557   expectKnownFPClass(fcFinite & ~fcNegZero & ~fcSubnormal, std::nullopt, A2);
1558   expectKnownFPClass(~(fcNan | fcNegZero | fcSubnormal), std::nullopt, A3);
1559 }
1560 
1561 TEST_F(ComputeKnownFPClassTest, FAdd) {
1562   parseAssembly(
1563       "define float @test(float nofpclass(nan inf) %nnan.ninf, float nofpclass(nan) %nnan, float nofpclass(qnan) %no.qnan, float %unknown) {\n"
1564       "  %A = fadd float %nnan, %nnan.ninf"
1565       "  %A2 = fadd float %nnan.ninf, %nnan"
1566       "  %A3 = fadd float %nnan.ninf, %unknown"
1567       "  %A4 = fadd float %nnan.ninf, %no.qnan"
1568       "  %A5 = fadd float %nnan, %nnan"
1569       "  ret float %A\n"
1570       "}\n");
1571   expectKnownFPClass(fcFinite | fcInf, std::nullopt, A);
1572   expectKnownFPClass(fcFinite | fcInf, std::nullopt, A2);
1573   expectKnownFPClass(fcAllFlags, std::nullopt, A3);
1574   expectKnownFPClass(fcAllFlags, std::nullopt, A4);
1575   expectKnownFPClass(fcAllFlags, std::nullopt, A5);
1576 }
1577 
1578 TEST_F(ComputeKnownFPClassTest, FSub) {
1579   parseAssembly(
1580       "define float @test(float nofpclass(nan inf) %nnan.ninf, float nofpclass(nan) %nnan, float nofpclass(qnan) %no.qnan, float %unknown) {\n"
1581       "  %A = fsub float %nnan, %nnan.ninf"
1582       "  %A2 = fsub float %nnan.ninf, %nnan"
1583       "  %A3 = fsub float %nnan.ninf, %unknown"
1584       "  %A4 = fsub float %nnan.ninf, %no.qnan"
1585       "  %A5 = fsub float %nnan, %nnan"
1586       "  ret float %A\n"
1587       "}\n");
1588   expectKnownFPClass(fcFinite | fcInf, std::nullopt, A);
1589   expectKnownFPClass(fcFinite | fcInf, std::nullopt, A2);
1590   expectKnownFPClass(fcAllFlags, std::nullopt, A3);
1591   expectKnownFPClass(fcAllFlags, std::nullopt, A4);
1592   expectKnownFPClass(fcAllFlags, std::nullopt, A5);
1593 }
1594 
1595 TEST_F(ComputeKnownFPClassTest, FMul) {
1596   parseAssembly(
1597       "define float @test(float nofpclass(nan inf) %nnan.ninf0, float nofpclass(nan inf) %nnan.ninf1, float nofpclass(nan) %nnan, float nofpclass(qnan) %no.qnan, float %unknown) {\n"
1598       "  %A = fmul float %nnan.ninf0, %nnan.ninf1"
1599       "  %A2 = fmul float %nnan.ninf0, %nnan"
1600       "  %A3 = fmul float %nnan, %nnan.ninf0"
1601       "  %A4 = fmul float %nnan.ninf0, %no.qnan"
1602       "  %A5 = fmul float %nnan, %nnan"
1603       "  ret float %A\n"
1604       "}\n");
1605   expectKnownFPClass(fcFinite | fcInf, std::nullopt, A);
1606   expectKnownFPClass(fcAllFlags, std::nullopt, A2);
1607   expectKnownFPClass(fcAllFlags, std::nullopt, A3);
1608   expectKnownFPClass(fcAllFlags, std::nullopt, A4);
1609   expectKnownFPClass(fcPositive | fcNan, std::nullopt, A5);
1610 }
1611 
1612 TEST_F(ComputeKnownFPClassTest, FMulNoZero) {
1613   parseAssembly(
1614       "define float @test(float nofpclass(zero) %no.zero, float nofpclass(zero nan) %no.zero.nan0, float nofpclass(zero nan) %no.zero.nan1, float nofpclass(nzero nan) %no.negzero.nan, float nofpclass(pzero nan) %no.poszero.nan, float nofpclass(inf nan) %no.inf.nan, float nofpclass(inf) %no.inf, float nofpclass(nan) %no.nan) {\n"
1615       "  %A = fmul float %no.zero.nan0, %no.zero.nan1"
1616       "  %A2 = fmul float %no.zero, %no.zero"
1617       "  %A3 = fmul float %no.poszero.nan, %no.zero.nan0"
1618       "  %A4 = fmul float %no.nan, %no.zero"
1619       "  %A5 = fmul float %no.zero, %no.inf"
1620       "  %A6 = fmul float %no.zero.nan0, %no.nan"
1621       "  %A7 = fmul float %no.nan, %no.zero.nan0"
1622       "  ret float %A\n"
1623       "}\n");
1624   expectKnownFPClass(fcFinite | fcInf, std::nullopt, A);
1625   expectKnownFPClass(fcPositive | fcNan, std::nullopt, A2);
1626   expectKnownFPClass(fcAllFlags, std::nullopt, A3);
1627   expectKnownFPClass(fcAllFlags, std::nullopt, A4);
1628   expectKnownFPClass(fcAllFlags, std::nullopt, A5);
1629   expectKnownFPClass(fcAllFlags, std::nullopt, A6);
1630   expectKnownFPClass(fcAllFlags, std::nullopt, A7);
1631 }
1632 
1633 TEST_F(ComputeKnownFPClassTest, Phi) {
1634   parseAssembly(
1635       "define float @test(i1 %cond, float nofpclass(nan inf) %arg0, float nofpclass(nan) %arg1) {\n"
1636       "entry:\n"
1637       "  br i1 %cond, label %bb0, label %bb1\n"
1638       "bb0:\n"
1639       "  br label %ret\n"
1640       "bb1:\n"
1641       "  br label %ret\n"
1642       "ret:\n"
1643       "  %A = phi float [ %arg0, %bb0 ],  [ %arg1, %bb1 ]\n"
1644       "  ret float %A\n"
1645       "}\n");
1646   expectKnownFPClass(~fcNan, std::nullopt);
1647 }
1648 
1649 TEST_F(ComputeKnownFPClassTest, PhiKnownSignFalse) {
1650   parseAssembly(
1651       "declare float @llvm.fabs.f32(float)"
1652       "define float @test(i1 %cond, float nofpclass(nan) %arg0, float nofpclass(nan) %arg1) {\n"
1653       "entry:\n"
1654       "  br i1 %cond, label %bb0, label %bb1\n"
1655       "bb0:\n"
1656       "  %fabs.arg0 = call float @llvm.fabs.f32(float %arg0)\n"
1657       "  br label %ret\n"
1658       "bb1:\n"
1659       "  %fabs.arg1 = call float @llvm.fabs.f32(float %arg1)\n"
1660       "  br label %ret\n"
1661       "ret:\n"
1662       "  %A = phi float [ %fabs.arg0, %bb0 ],  [ %fabs.arg1, %bb1 ]\n"
1663       "  ret float %A\n"
1664       "}\n");
1665   expectKnownFPClass(fcPositive, false);
1666 }
1667 
1668 TEST_F(ComputeKnownFPClassTest, PhiKnownSignTrue) {
1669   parseAssembly(
1670       "declare float @llvm.fabs.f32(float)"
1671       "define float @test(i1 %cond, float nofpclass(nan) %arg0, float %arg1) {\n"
1672       "entry:\n"
1673       "  br i1 %cond, label %bb0, label %bb1\n"
1674       "bb0:\n"
1675       "  %fabs.arg0 = call float @llvm.fabs.f32(float %arg0)\n"
1676       "  %fneg.fabs.arg0 = fneg float %fabs.arg0\n"
1677       "  br label %ret\n"
1678       "bb1:\n"
1679       "  %fabs.arg1 = call float @llvm.fabs.f32(float %arg1)\n"
1680       "  %fneg.fabs.arg1 = fneg float %fabs.arg1\n"
1681       "  br label %ret\n"
1682       "ret:\n"
1683       "  %A = phi float [ %fneg.fabs.arg0, %bb0 ],  [ %fneg.fabs.arg1, %bb1 ]\n"
1684       "  ret float %A\n"
1685       "}\n");
1686   expectKnownFPClass(fcNegative | fcNan, true);
1687 }
1688 
1689 TEST_F(ComputeKnownFPClassTest, UnreachablePhi) {
1690   parseAssembly(
1691       "define float @test(float %arg) {\n"
1692       "entry:\n"
1693       "  ret float 0.0\n"
1694       "unreachable:\n"
1695       "  %A = phi float\n"
1696       "  ret float %A\n"
1697       "}\n");
1698   expectKnownFPClass(fcAllFlags, std::nullopt);
1699 }
1700 
1701 TEST_F(ComputeKnownFPClassTest, SelfPhiOnly) {
1702   parseAssembly(
1703       "define float @test(float %arg) {\n"
1704       "entry:\n"
1705       "  ret float 0.0\n"
1706       "loop:\n"
1707       "  %A = phi float [ %A, %loop ]\n"
1708       "  br label %loop\n"
1709       "}\n");
1710   expectKnownFPClass(fcAllFlags, std::nullopt);
1711 }
1712 
1713 TEST_F(ComputeKnownFPClassTest, SelfPhiFirstArg) {
1714   parseAssembly(
1715       "define float @test(i1 %cond, float nofpclass(inf) %arg) {\n"
1716       "entry:\n"
1717       "  br i1 %cond, label %loop, label %ret\n"
1718       "loop:\n"
1719       "  %A = phi float [ %arg, %entry ], [ %A, %loop ]\n"
1720       "  br label %loop\n"
1721       "ret:\n"
1722       "  ret float %A"
1723       "}\n");
1724   expectKnownFPClass(~fcInf, std::nullopt);
1725 }
1726 
1727 TEST_F(ComputeKnownFPClassTest, SelfPhiSecondArg) {
1728   parseAssembly(
1729       "define float @test(i1 %cond, float nofpclass(inf) %arg) {\n"
1730       "entry:\n"
1731       "  br i1 %cond, label %loop, label %ret\n"
1732       "loop:\n"
1733       "  %A = phi float [ %A, %loop ], [ %arg, %entry ]\n"
1734       "  br label %loop\n"
1735       "ret:\n"
1736       "  ret float %A"
1737       "}\n");
1738   expectKnownFPClass(~fcInf, std::nullopt);
1739 }
1740 
1741 TEST_F(ComputeKnownFPClassTest, CannotBeOrderedLessThanZero) {
1742   parseAssembly("define float @test(float %arg) {\n"
1743                 "  %A = fmul float %arg, %arg"
1744                 "  ret float %A\n"
1745                 "}\n");
1746 
1747   Type *FPTy = Type::getDoubleTy(M->getContext());
1748   const DataLayout &DL = M->getDataLayout();
1749 
1750   EXPECT_TRUE(
1751       computeKnownFPClass(ConstantFP::getZero(FPTy, /*Negative=*/false), DL)
1752           .cannotBeOrderedLessThanZero());
1753   EXPECT_TRUE(
1754       computeKnownFPClass(ConstantFP::getZero(FPTy, /*Negative=*/true), DL)
1755           .cannotBeOrderedLessThanZero());
1756 
1757   EXPECT_TRUE(computeKnownFPClass(ConstantFP::getInfinity(FPTy, false), DL)
1758                   .cannotBeOrderedLessThanZero());
1759   EXPECT_FALSE(computeKnownFPClass(ConstantFP::getInfinity(FPTy, true), DL)
1760                    .cannotBeOrderedLessThanZero());
1761 
1762   EXPECT_TRUE(computeKnownFPClass(ConstantFP::get(FPTy, 1.0), DL)
1763                   .cannotBeOrderedLessThanZero());
1764   EXPECT_FALSE(computeKnownFPClass(ConstantFP::get(FPTy, -1.0), DL)
1765                    .cannotBeOrderedLessThanZero());
1766 
1767   EXPECT_TRUE(
1768       computeKnownFPClass(
1769           ConstantFP::get(FPTy, APFloat::getSmallest(FPTy->getFltSemantics(),
1770                                                      /*Negative=*/false)),
1771           DL)
1772           .cannotBeOrderedLessThanZero());
1773   EXPECT_FALSE(
1774       computeKnownFPClass(
1775           ConstantFP::get(FPTy, APFloat::getSmallest(FPTy->getFltSemantics(),
1776                                                      /*Negative=*/true)),
1777           DL)
1778           .cannotBeOrderedLessThanZero());
1779 
1780   EXPECT_TRUE(
1781       computeKnownFPClass(ConstantFP::getQNaN(FPTy, /*Negative=*/false), DL)
1782           .cannotBeOrderedLessThanZero());
1783   EXPECT_TRUE(
1784       computeKnownFPClass(ConstantFP::getQNaN(FPTy, /*Negative=*/true), DL)
1785           .cannotBeOrderedLessThanZero());
1786   EXPECT_TRUE(
1787       computeKnownFPClass(ConstantFP::getSNaN(FPTy, /*Negative=*/false), DL)
1788           .cannotBeOrderedLessThanZero());
1789   EXPECT_TRUE(
1790       computeKnownFPClass(ConstantFP::getSNaN(FPTy, /*Negative=*/true), DL)
1791           .cannotBeOrderedLessThanZero());
1792 }
1793 
1794 TEST_F(ComputeKnownFPClassTest, FCmpToClassTest_OrdNan) {
1795   parseAssembly("define i1 @test(double %arg) {\n"
1796                 "  %A = fcmp ord double %arg, 0x7FF8000000000000"
1797                 "  %A2 = fcmp uno double %arg, 0x7FF8000000000000"
1798                 "  %A3 = fcmp oeq double %arg, 0x7FF8000000000000"
1799                 "  %A4 = fcmp ueq double %arg, 0x7FF8000000000000"
1800                 "  ret i1 %A\n"
1801                 "}\n");
1802 
1803   auto [OrdVal, OrdClass] = fcmpToClassTest(
1804       CmpInst::FCMP_ORD, *A->getFunction(), A->getOperand(0), A->getOperand(1));
1805   EXPECT_EQ(A->getOperand(0), OrdVal);
1806   EXPECT_EQ(fcNone, OrdClass);
1807 
1808   auto [UnordVal, UnordClass] =
1809       fcmpToClassTest(CmpInst::FCMP_UNO, *A2->getFunction(), A2->getOperand(0),
1810                       A2->getOperand(1));
1811   EXPECT_EQ(A2->getOperand(0), UnordVal);
1812   EXPECT_EQ(fcAllFlags, UnordClass);
1813 
1814   auto [OeqVal, OeqClass] =
1815       fcmpToClassTest(CmpInst::FCMP_OEQ, *A3->getFunction(), A3->getOperand(0),
1816                       A3->getOperand(1));
1817   EXPECT_EQ(A3->getOperand(0), OeqVal);
1818   EXPECT_EQ(fcNone, OeqClass);
1819 
1820   auto [UeqVal, UeqClass] =
1821       fcmpToClassTest(CmpInst::FCMP_UEQ, *A3->getFunction(), A3->getOperand(0),
1822                       A3->getOperand(1));
1823   EXPECT_EQ(A3->getOperand(0), UeqVal);
1824   EXPECT_EQ(fcAllFlags, UeqClass);
1825 }
1826 
1827 TEST_F(ComputeKnownFPClassTest, FCmpToClassTest_NInf) {
1828   parseAssembly("define i1 @test(double %arg) {\n"
1829                 "  %A = fcmp olt double %arg, 0xFFF0000000000000"
1830                 "  %A2 = fcmp uge double %arg, 0xFFF0000000000000"
1831                 "  %A3 = fcmp ogt double %arg, 0xFFF0000000000000"
1832                 "  %A4 = fcmp ule double %arg, 0xFFF0000000000000"
1833                 "  %A5 = fcmp oge double %arg, 0xFFF0000000000000"
1834                 "  %A6 = fcmp ult double %arg, 0xFFF0000000000000"
1835                 "  ret i1 %A\n"
1836                 "}\n");
1837 
1838   auto [OltVal, OltClass] = fcmpToClassTest(
1839       CmpInst::FCMP_OLT, *A->getFunction(), A->getOperand(0), A->getOperand(1));
1840   EXPECT_EQ(A->getOperand(0), OltVal);
1841   EXPECT_EQ(fcNone, OltClass);
1842 
1843   auto [UgeVal, UgeClass] =
1844       fcmpToClassTest(CmpInst::FCMP_UGE, *A2->getFunction(), A2->getOperand(0),
1845                       A2->getOperand(1));
1846   EXPECT_EQ(A2->getOperand(0), UgeVal);
1847   EXPECT_EQ(fcAllFlags, UgeClass);
1848 
1849   auto [OgtVal, OgtClass] =
1850       fcmpToClassTest(CmpInst::FCMP_OGT, *A3->getFunction(), A3->getOperand(0),
1851                       A3->getOperand(1));
1852   EXPECT_EQ(A3->getOperand(0), OgtVal);
1853   EXPECT_EQ(~(fcNegInf | fcNan), OgtClass);
1854 
1855   auto [UleVal, UleClass] =
1856       fcmpToClassTest(CmpInst::FCMP_ULE, *A4->getFunction(), A4->getOperand(0),
1857                       A4->getOperand(1));
1858   EXPECT_EQ(A4->getOperand(0), UleVal);
1859   EXPECT_EQ(fcNegInf | fcNan, UleClass);
1860 
1861   auto [OgeVal, OgeClass] =
1862       fcmpToClassTest(CmpInst::FCMP_OGE, *A5->getFunction(), A5->getOperand(0),
1863                       A5->getOperand(1));
1864   EXPECT_EQ(A5->getOperand(0), OgeVal);
1865   EXPECT_EQ(~fcNan, OgeClass);
1866 
1867   auto [UltVal, UltClass] =
1868       fcmpToClassTest(CmpInst::FCMP_ULT, *A6->getFunction(), A6->getOperand(0),
1869                       A6->getOperand(1));
1870   EXPECT_EQ(A6->getOperand(0), UltVal);
1871   EXPECT_EQ(fcNan, UltClass);
1872 }
1873 
1874 TEST_F(ComputeKnownFPClassTest, FCmpToClassTest_FabsNInf) {
1875   parseAssembly("declare double @llvm.fabs.f64(double)\n"
1876                 "define i1 @test(double %arg) {\n"
1877                 "  %fabs.arg = call double @llvm.fabs.f64(double %arg)\n"
1878                 "  %A = fcmp olt double %fabs.arg, 0xFFF0000000000000"
1879                 "  %A2 = fcmp uge double %fabs.arg, 0xFFF0000000000000"
1880                 "  %A3 = fcmp ogt double %fabs.arg, 0xFFF0000000000000"
1881                 "  %A4 = fcmp ule double %fabs.arg, 0xFFF0000000000000"
1882                 "  %A5 = fcmp oge double %fabs.arg, 0xFFF0000000000000"
1883                 "  %A6 = fcmp ult double %fabs.arg, 0xFFF0000000000000"
1884                 "  ret i1 %A\n"
1885                 "}\n");
1886 
1887   Value *ArgVal = F->getArg(0);
1888 
1889   auto [OltVal, OltClass] = fcmpToClassTest(
1890       CmpInst::FCMP_OLT, *A->getFunction(), A->getOperand(0), A->getOperand(1));
1891   EXPECT_EQ(ArgVal, OltVal);
1892   EXPECT_EQ(fcNone, OltClass);
1893 
1894   auto [UgeVal, UgeClass] =
1895       fcmpToClassTest(CmpInst::FCMP_UGE, *A2->getFunction(), A2->getOperand(0),
1896                       A2->getOperand(1));
1897   EXPECT_EQ(ArgVal, UgeVal);
1898   EXPECT_EQ(fcAllFlags, UgeClass);
1899 
1900   auto [OgtVal, OgtClass] =
1901       fcmpToClassTest(CmpInst::FCMP_OGT, *A3->getFunction(), A3->getOperand(0),
1902                       A3->getOperand(1));
1903   EXPECT_EQ(ArgVal, OgtVal);
1904   EXPECT_EQ(~fcNan, OgtClass);
1905 
1906   auto [UleVal, UleClass] =
1907       fcmpToClassTest(CmpInst::FCMP_ULE, *A4->getFunction(), A4->getOperand(0),
1908                       A4->getOperand(1));
1909   EXPECT_EQ(ArgVal, UleVal);
1910   EXPECT_EQ(fcNan, UleClass);
1911 
1912   auto [OgeVal, OgeClass] =
1913       fcmpToClassTest(CmpInst::FCMP_OGE, *A5->getFunction(), A5->getOperand(0),
1914                       A5->getOperand(1));
1915   EXPECT_EQ(ArgVal, OgeVal);
1916   EXPECT_EQ(~fcNan, OgeClass);
1917 
1918   auto [UltVal, UltClass] =
1919       fcmpToClassTest(CmpInst::FCMP_ULT, *A6->getFunction(), A6->getOperand(0),
1920                       A6->getOperand(1));
1921   EXPECT_EQ(ArgVal, UltVal);
1922   EXPECT_EQ(fcNan, UltClass);
1923 }
1924 
1925 TEST_F(ComputeKnownFPClassTest, FCmpToClassTest_PInf) {
1926   parseAssembly("define i1 @test(double %arg) {\n"
1927                 "  %A = fcmp ogt double %arg, 0x7FF0000000000000"
1928                 "  %A2 = fcmp ule double %arg, 0x7FF0000000000000"
1929                 "  %A3 = fcmp ole double %arg, 0x7FF0000000000000"
1930                 "  %A4 = fcmp ugt double %arg, 0x7FF0000000000000"
1931                 "  ret i1 %A\n"
1932                 "}\n");
1933 
1934   auto [OgtVal, OgtClass] = fcmpToClassTest(
1935       CmpInst::FCMP_OGT, *A->getFunction(), A->getOperand(0), A->getOperand(1));
1936   EXPECT_EQ(A->getOperand(0), OgtVal);
1937   EXPECT_EQ(fcNone, OgtClass);
1938 
1939   auto [UleVal, UleClass] =
1940       fcmpToClassTest(CmpInst::FCMP_ULE, *A2->getFunction(), A2->getOperand(0),
1941                       A2->getOperand(1));
1942   EXPECT_EQ(A2->getOperand(0), UleVal);
1943   EXPECT_EQ(fcAllFlags, UleClass);
1944 
1945   auto [OleVal, OleClass] =
1946       fcmpToClassTest(CmpInst::FCMP_OLE, *A3->getFunction(), A3->getOperand(0),
1947                       A3->getOperand(1));
1948   EXPECT_EQ(nullptr, OleVal);
1949   EXPECT_EQ(fcAllFlags, OleClass);
1950 
1951   auto [UgtVal, UgtClass] =
1952       fcmpToClassTest(CmpInst::FCMP_UGT, *A4->getFunction(), A4->getOperand(0),
1953                       A4->getOperand(1));
1954   EXPECT_EQ(nullptr, UgtVal);
1955   EXPECT_EQ(fcAllFlags, UgtClass);
1956 }
1957 
1958 TEST_F(ComputeKnownFPClassTest, SqrtNszSignBit) {
1959   parseAssembly(
1960       "declare float @llvm.sqrt.f32(float)\n"
1961       "define float @test(float %arg, float nofpclass(nan) %arg.nnan) {\n"
1962       "  %A = call float @llvm.sqrt.f32(float %arg)\n"
1963       "  %A2 = call nsz float @llvm.sqrt.f32(float %arg)\n"
1964       "  %A3 = call float @llvm.sqrt.f32(float %arg.nnan)\n"
1965       "  %A4 = call nsz float @llvm.sqrt.f32(float %arg.nnan)\n"
1966       "  ret float %A\n"
1967       "}\n");
1968 
1969   const FPClassTest SqrtMask = fcPositive | fcNegZero | fcNan;
1970   const FPClassTest NszSqrtMask = fcPositive | fcNan;
1971 
1972   {
1973     KnownFPClass UseInstrInfo =
1974         computeKnownFPClass(A, M->getDataLayout(), fcAllFlags, 0, nullptr,
1975                             nullptr, nullptr, nullptr, /*UseInstrInfo=*/true);
1976     EXPECT_EQ(SqrtMask, UseInstrInfo.KnownFPClasses);
1977     EXPECT_EQ(std::nullopt, UseInstrInfo.SignBit);
1978 
1979     KnownFPClass NoUseInstrInfo =
1980         computeKnownFPClass(A, M->getDataLayout(), fcAllFlags, 0, nullptr,
1981                             nullptr, nullptr, nullptr, /*UseInstrInfo=*/false);
1982     EXPECT_EQ(SqrtMask, NoUseInstrInfo.KnownFPClasses);
1983     EXPECT_EQ(std::nullopt, NoUseInstrInfo.SignBit);
1984   }
1985 
1986   {
1987     KnownFPClass UseInstrInfoNSZ =
1988         computeKnownFPClass(A2, M->getDataLayout(), fcAllFlags, 0, nullptr,
1989                             nullptr, nullptr, nullptr, /*UseInstrInfo=*/true);
1990     EXPECT_EQ(NszSqrtMask, UseInstrInfoNSZ.KnownFPClasses);
1991     EXPECT_EQ(std::nullopt, UseInstrInfoNSZ.SignBit);
1992 
1993     KnownFPClass NoUseInstrInfoNSZ =
1994         computeKnownFPClass(A2, M->getDataLayout(), fcAllFlags, 0, nullptr,
1995                             nullptr, nullptr, nullptr, /*UseInstrInfo=*/false);
1996     EXPECT_EQ(SqrtMask, NoUseInstrInfoNSZ.KnownFPClasses);
1997     EXPECT_EQ(std::nullopt, NoUseInstrInfoNSZ.SignBit);
1998   }
1999 
2000   {
2001     KnownFPClass UseInstrInfoNoNan =
2002         computeKnownFPClass(A3, M->getDataLayout(), fcAllFlags, 0, nullptr,
2003                             nullptr, nullptr, nullptr, /*UseInstrInfo=*/true);
2004     EXPECT_EQ(fcPositive | fcNegZero | fcQNan,
2005               UseInstrInfoNoNan.KnownFPClasses);
2006     EXPECT_EQ(std::nullopt, UseInstrInfoNoNan.SignBit);
2007 
2008     KnownFPClass NoUseInstrInfoNoNan =
2009         computeKnownFPClass(A3, M->getDataLayout(), fcAllFlags, 0, nullptr,
2010                             nullptr, nullptr, nullptr, /*UseInstrInfo=*/false);
2011     EXPECT_EQ(fcPositive | fcNegZero | fcQNan,
2012               NoUseInstrInfoNoNan.KnownFPClasses);
2013     EXPECT_EQ(std::nullopt, NoUseInstrInfoNoNan.SignBit);
2014   }
2015 
2016   {
2017     KnownFPClass UseInstrInfoNSZNoNan =
2018         computeKnownFPClass(A4, M->getDataLayout(), fcAllFlags, 0, nullptr,
2019                             nullptr, nullptr, nullptr, /*UseInstrInfo=*/true);
2020     EXPECT_EQ(fcPositive | fcQNan, UseInstrInfoNSZNoNan.KnownFPClasses);
2021     EXPECT_EQ(false, UseInstrInfoNSZNoNan.SignBit);
2022 
2023     KnownFPClass NoUseInstrInfoNSZNoNan =
2024         computeKnownFPClass(A4, M->getDataLayout(), fcAllFlags, 0, nullptr,
2025                             nullptr, nullptr, nullptr, /*UseInstrInfo=*/false);
2026     EXPECT_EQ(fcPositive | fcNegZero | fcQNan,
2027               NoUseInstrInfoNSZNoNan.KnownFPClasses);
2028     EXPECT_EQ(std::nullopt, NoUseInstrInfoNSZNoNan.SignBit);
2029   }
2030 }
2031 
2032 TEST_F(ValueTrackingTest, isNonZeroRecurrence) {
2033   parseAssembly(R"(
2034     define i1 @test(i8 %n, i8 %r) {
2035     entry:
2036       br label %loop
2037     loop:
2038       %p = phi i8 [ -1, %entry ], [ %next, %loop ]
2039       %next = add nsw i8 %p, -1
2040       %cmp1 = icmp eq i8 %p, %n
2041       br i1 %cmp1, label %exit, label %loop
2042     exit:
2043       %A = or i8 %p, %r
2044       %CxtI = icmp eq i8 %A, 0
2045       ret i1 %CxtI
2046     }
2047   )");
2048   const DataLayout &DL = M->getDataLayout();
2049   AssumptionCache AC(*F);
2050   EXPECT_TRUE(isKnownNonZero(A, DL, 0, &AC, CxtI));
2051 }
2052 
2053 TEST_F(ValueTrackingTest, KnownNonZeroFromDomCond) {
2054   parseAssembly(R"(
2055     declare ptr @f_i8()
2056     define void @test(i1 %c) {
2057       %A = call ptr @f_i8()
2058       %B = call ptr @f_i8()
2059       %c1 = icmp ne ptr %A, null
2060       %cond = and i1 %c1, %c
2061       br i1 %cond, label %T, label %Q
2062     T:
2063       %CxtI = add i32 0, 0
2064       ret void
2065     Q:
2066       %CxtI2 = add i32 0, 0
2067       ret void
2068     }
2069   )");
2070   AssumptionCache AC(*F);
2071   DominatorTree DT(*F);
2072   const DataLayout &DL = M->getDataLayout();
2073   EXPECT_EQ(isKnownNonZero(A, DL, 0, &AC, CxtI, &DT), true);
2074   EXPECT_EQ(isKnownNonZero(A, DL, 0, &AC, CxtI2, &DT), false);
2075 }
2076 
2077 TEST_F(ValueTrackingTest, KnownNonZeroFromDomCond2) {
2078   parseAssembly(R"(
2079     declare ptr @f_i8()
2080     define void @test(i1 %c) {
2081       %A = call ptr @f_i8()
2082       %B = call ptr @f_i8()
2083       %c1 = icmp ne ptr %A, null
2084       %cond = select i1 %c, i1 %c1, i1 false
2085       br i1 %cond, label %T, label %Q
2086     T:
2087       %CxtI = add i32 0, 0
2088       ret void
2089     Q:
2090       %CxtI2 = add i32 0, 0
2091       ret void
2092     }
2093   )");
2094   AssumptionCache AC(*F);
2095   DominatorTree DT(*F);
2096   const DataLayout &DL = M->getDataLayout();
2097   EXPECT_EQ(isKnownNonZero(A, DL, 0, &AC, CxtI, &DT), true);
2098   EXPECT_EQ(isKnownNonZero(A, DL, 0, &AC, CxtI2, &DT), false);
2099 }
2100 
2101 TEST_F(ValueTrackingTest, IsImpliedConditionAnd) {
2102   parseAssembly(R"(
2103     define void @test(i32 %x, i32 %y) {
2104       %c1 = icmp ult i32 %x, 10
2105       %c2 = icmp ult i32 %y, 15
2106       %A = and i1 %c1, %c2
2107       ; x < 10 /\ y < 15
2108       %A2 = icmp ult i32 %x, 20
2109       %A3 = icmp uge i32 %y, 20
2110       %A4 = icmp ult i32 %x, 5
2111       ret void
2112     }
2113   )");
2114   const DataLayout &DL = M->getDataLayout();
2115   EXPECT_EQ(isImpliedCondition(A, A2, DL), true);
2116   EXPECT_EQ(isImpliedCondition(A, A3, DL), false);
2117   EXPECT_EQ(isImpliedCondition(A, A4, DL), std::nullopt);
2118 }
2119 
2120 TEST_F(ValueTrackingTest, IsImpliedConditionAnd2) {
2121   parseAssembly(R"(
2122     define void @test(i32 %x, i32 %y) {
2123       %c1 = icmp ult i32 %x, 10
2124       %c2 = icmp ult i32 %y, 15
2125       %A = select i1 %c1, i1 %c2, i1 false
2126       ; x < 10 /\ y < 15
2127       %A2 = icmp ult i32 %x, 20
2128       %A3 = icmp uge i32 %y, 20
2129       %A4 = icmp ult i32 %x, 5
2130       ret void
2131     }
2132   )");
2133   const DataLayout &DL = M->getDataLayout();
2134   EXPECT_EQ(isImpliedCondition(A, A2, DL), true);
2135   EXPECT_EQ(isImpliedCondition(A, A3, DL), false);
2136   EXPECT_EQ(isImpliedCondition(A, A4, DL), std::nullopt);
2137 }
2138 
2139 TEST_F(ValueTrackingTest, IsImpliedConditionAndVec) {
2140   parseAssembly(R"(
2141     define void @test(<2 x i8> %x, <2 x i8> %y) {
2142       %A = icmp ult <2 x i8> %x, %y
2143       %A2 = icmp ule <2 x i8> %x, %y
2144       ret void
2145     }
2146   )");
2147   const DataLayout &DL = M->getDataLayout();
2148   EXPECT_EQ(isImpliedCondition(A, A2, DL), true);
2149 }
2150 
2151 TEST_F(ValueTrackingTest, IsImpliedConditionOr) {
2152   parseAssembly(R"(
2153     define void @test(i32 %x, i32 %y) {
2154       %c1 = icmp ult i32 %x, 10
2155       %c2 = icmp ult i32 %y, 15
2156       %A = or i1 %c1, %c2 ; negated
2157       ; x >= 10 /\ y >= 15
2158       %A2 = icmp ult i32 %x, 5
2159       %A3 = icmp uge i32 %y, 10
2160       %A4 = icmp ult i32 %x, 15
2161       ret void
2162     }
2163   )");
2164   const DataLayout &DL = M->getDataLayout();
2165   EXPECT_EQ(isImpliedCondition(A, A2, DL, false), false);
2166   EXPECT_EQ(isImpliedCondition(A, A3, DL, false), true);
2167   EXPECT_EQ(isImpliedCondition(A, A4, DL, false), std::nullopt);
2168 }
2169 
2170 TEST_F(ValueTrackingTest, IsImpliedConditionOr2) {
2171   parseAssembly(R"(
2172     define void @test(i32 %x, i32 %y) {
2173       %c1 = icmp ult i32 %x, 10
2174       %c2 = icmp ult i32 %y, 15
2175       %A = select i1 %c1, i1 true, i1 %c2 ; negated
2176       ; x >= 10 /\ y >= 15
2177       %A2 = icmp ult i32 %x, 5
2178       %A3 = icmp uge i32 %y, 10
2179       %A4 = icmp ult i32 %x, 15
2180       ret void
2181     }
2182   )");
2183   const DataLayout &DL = M->getDataLayout();
2184   EXPECT_EQ(isImpliedCondition(A, A2, DL, false), false);
2185   EXPECT_EQ(isImpliedCondition(A, A3, DL, false), true);
2186   EXPECT_EQ(isImpliedCondition(A, A4, DL, false), std::nullopt);
2187 }
2188 
2189 TEST_F(ComputeKnownBitsTest, KnownNonZeroShift) {
2190   // %q is known nonzero without known bits.
2191   // Because %q is nonzero, %A[0] is known to be zero.
2192   parseAssembly(
2193       "define i8 @test(i8 %p, ptr %pq) {\n"
2194       "  %q = load i8, ptr %pq, !range !0\n"
2195       "  %A = shl i8 %p, %q\n"
2196       "  ret i8 %A\n"
2197       "}\n"
2198       "!0 = !{ i8 1, i8 5 }\n");
2199   expectKnownBits(/*zero*/ 1u, /*one*/ 0u);
2200 }
2201 
2202 TEST_F(ComputeKnownBitsTest, ComputeKnownFshl) {
2203   // fshl(....1111....0000, 00..1111........, 6)
2204   // = 11....000000..11
2205   parseAssembly(
2206       "define i16 @test(i16 %a, i16 %b) {\n"
2207       "  %aa = shl i16 %a, 4\n"
2208       "  %bb = lshr i16 %b, 2\n"
2209       "  %aaa = or i16 %aa, 3840\n"
2210       "  %bbb = or i16 %bb, 3840\n"
2211       "  %A = call i16 @llvm.fshl.i16(i16 %aaa, i16 %bbb, i16 6)\n"
2212       "  ret i16 %A\n"
2213       "}\n"
2214       "declare i16 @llvm.fshl.i16(i16, i16, i16)\n");
2215   expectKnownBits(/*zero*/ 1008u, /*one*/ 49155u);
2216 }
2217 
2218 TEST_F(ComputeKnownBitsTest, ComputeKnownFshr) {
2219   // fshr(....1111....0000, 00..1111........, 26)
2220   // = 11....000000..11
2221   parseAssembly(
2222       "define i16 @test(i16 %a, i16 %b) {\n"
2223       "  %aa = shl i16 %a, 4\n"
2224       "  %bb = lshr i16 %b, 2\n"
2225       "  %aaa = or i16 %aa, 3840\n"
2226       "  %bbb = or i16 %bb, 3840\n"
2227       "  %A = call i16 @llvm.fshr.i16(i16 %aaa, i16 %bbb, i16 26)\n"
2228       "  ret i16 %A\n"
2229       "}\n"
2230       "declare i16 @llvm.fshr.i16(i16, i16, i16)\n");
2231   expectKnownBits(/*zero*/ 1008u, /*one*/ 49155u);
2232 }
2233 
2234 TEST_F(ComputeKnownBitsTest, ComputeKnownFshlZero) {
2235   // fshl(....1111....0000, 00..1111........, 0)
2236   // = ....1111....0000
2237   parseAssembly(
2238       "define i16 @test(i16 %a, i16 %b) {\n"
2239       "  %aa = shl i16 %a, 4\n"
2240       "  %bb = lshr i16 %b, 2\n"
2241       "  %aaa = or i16 %aa, 3840\n"
2242       "  %bbb = or i16 %bb, 3840\n"
2243       "  %A = call i16 @llvm.fshl.i16(i16 %aaa, i16 %bbb, i16 0)\n"
2244       "  ret i16 %A\n"
2245       "}\n"
2246       "declare i16 @llvm.fshl.i16(i16, i16, i16)\n");
2247   expectKnownBits(/*zero*/ 15u, /*one*/ 3840u);
2248 }
2249 
2250 TEST_F(ComputeKnownBitsTest, ComputeKnownUAddSatLeadingOnes) {
2251   // uadd.sat(1111...1, ........)
2252   // = 1111....
2253   parseAssembly(
2254       "define i8 @test(i8 %a, i8 %b) {\n"
2255       "  %aa = or i8 %a, 241\n"
2256       "  %A = call i8 @llvm.uadd.sat.i8(i8 %aa, i8 %b)\n"
2257       "  ret i8 %A\n"
2258       "}\n"
2259       "declare i8 @llvm.uadd.sat.i8(i8, i8)\n");
2260   expectKnownBits(/*zero*/ 0u, /*one*/ 240u);
2261 }
2262 
2263 TEST_F(ComputeKnownBitsTest, ComputeKnownUAddSatOnesPreserved) {
2264   // uadd.sat(00...011, .1...110)
2265   // = .......1
2266   parseAssembly(
2267       "define i8 @test(i8 %a, i8 %b) {\n"
2268       "  %aa = or i8 %a, 3\n"
2269       "  %aaa = and i8 %aa, 59\n"
2270       "  %bb = or i8 %b, 70\n"
2271       "  %bbb = and i8 %bb, 254\n"
2272       "  %A = call i8 @llvm.uadd.sat.i8(i8 %aaa, i8 %bbb)\n"
2273       "  ret i8 %A\n"
2274       "}\n"
2275       "declare i8 @llvm.uadd.sat.i8(i8, i8)\n");
2276   expectKnownBits(/*zero*/ 0u, /*one*/ 1u);
2277 }
2278 
2279 TEST_F(ComputeKnownBitsTest, ComputeKnownUSubSatLHSLeadingZeros) {
2280   // usub.sat(0000...0, ........)
2281   // = 0000....
2282   parseAssembly(
2283       "define i8 @test(i8 %a, i8 %b) {\n"
2284       "  %aa = and i8 %a, 14\n"
2285       "  %A = call i8 @llvm.usub.sat.i8(i8 %aa, i8 %b)\n"
2286       "  ret i8 %A\n"
2287       "}\n"
2288       "declare i8 @llvm.usub.sat.i8(i8, i8)\n");
2289   expectKnownBits(/*zero*/ 240u, /*one*/ 0u);
2290 }
2291 
2292 TEST_F(ComputeKnownBitsTest, ComputeKnownUSubSatRHSLeadingOnes) {
2293   // usub.sat(........, 1111...1)
2294   // = 0000....
2295   parseAssembly(
2296       "define i8 @test(i8 %a, i8 %b) {\n"
2297       "  %bb = or i8 %a, 241\n"
2298       "  %A = call i8 @llvm.usub.sat.i8(i8 %a, i8 %bb)\n"
2299       "  ret i8 %A\n"
2300       "}\n"
2301       "declare i8 @llvm.usub.sat.i8(i8, i8)\n");
2302   expectKnownBits(/*zero*/ 240u, /*one*/ 0u);
2303 }
2304 
2305 TEST_F(ComputeKnownBitsTest, ComputeKnownUSubSatZerosPreserved) {
2306   // usub.sat(11...011, .1...110)
2307   // = ......0.
2308   parseAssembly(
2309       "define i8 @test(i8 %a, i8 %b) {\n"
2310       "  %aa = or i8 %a, 195\n"
2311       "  %aaa = and i8 %aa, 251\n"
2312       "  %bb = or i8 %b, 70\n"
2313       "  %bbb = and i8 %bb, 254\n"
2314       "  %A = call i8 @llvm.usub.sat.i8(i8 %aaa, i8 %bbb)\n"
2315       "  ret i8 %A\n"
2316       "}\n"
2317       "declare i8 @llvm.usub.sat.i8(i8, i8)\n");
2318   expectKnownBits(/*zero*/ 2u, /*one*/ 0u);
2319 }
2320 
2321 TEST_F(ComputeKnownBitsTest, ComputeKnownBitsPtrToIntTrunc) {
2322   // ptrtoint truncates the pointer type. Make sure we don't crash.
2323   parseAssembly(
2324       "define void @test(ptr %p) {\n"
2325       "  %A = load ptr, ptr %p\n"
2326       "  %i = ptrtoint ptr %A to i32\n"
2327       "  %m = and i32 %i, 31\n"
2328       "  %c = icmp eq i32 %m, 0\n"
2329       "  call void @llvm.assume(i1 %c)\n"
2330       "  ret void\n"
2331       "}\n"
2332       "declare void @llvm.assume(i1)\n");
2333   AssumptionCache AC(*F);
2334   KnownBits Known = computeKnownBits(
2335       A, M->getDataLayout(), /* Depth */ 0, &AC, F->front().getTerminator());
2336   EXPECT_TRUE(Known.isUnknown());
2337 }
2338 
2339 TEST_F(ComputeKnownBitsTest, ComputeKnownBitsPtrToIntZext) {
2340   // ptrtoint zero extends the pointer type. Make sure we don't crash.
2341   parseAssembly(
2342       "define void @test(ptr %p) {\n"
2343       "  %A = load ptr, ptr %p\n"
2344       "  %i = ptrtoint ptr %A to i128\n"
2345       "  %m = and i128 %i, 31\n"
2346       "  %c = icmp eq i128 %m, 0\n"
2347       "  call void @llvm.assume(i1 %c)\n"
2348       "  ret void\n"
2349       "}\n"
2350       "declare void @llvm.assume(i1)\n");
2351   AssumptionCache AC(*F);
2352   KnownBits Known = computeKnownBits(
2353       A, M->getDataLayout(), /* Depth */ 0, &AC, F->front().getTerminator());
2354   EXPECT_TRUE(Known.isUnknown());
2355 }
2356 
2357 TEST_F(ComputeKnownBitsTest, ComputeKnownBitsFreeze) {
2358   parseAssembly("define void @test() {\n"
2359                 "  %m = call i32 @any_num()\n"
2360                 "  %A = freeze i32 %m\n"
2361                 "  %n = and i32 %m, 31\n"
2362                 "  %c = icmp eq i32 %n, 0\n"
2363                 "  call void @llvm.assume(i1 %c)\n"
2364                 "  ret void\n"
2365                 "}\n"
2366                 "declare void @llvm.assume(i1)\n"
2367                 "declare i32 @any_num()\n");
2368   AssumptionCache AC(*F);
2369   KnownBits Known = computeKnownBits(A, M->getDataLayout(), /* Depth */ 0, &AC,
2370                                      F->front().getTerminator());
2371   EXPECT_EQ(Known.Zero.getZExtValue(), 31u);
2372   EXPECT_EQ(Known.One.getZExtValue(), 0u);
2373 }
2374 
2375 TEST_F(ComputeKnownBitsTest, ComputeKnownBitsAddWithRange) {
2376   parseAssembly("define void @test(ptr %p) {\n"
2377                 "  %A = load i64, ptr %p, !range !{i64 64, i64 65536}\n"
2378                 "  %APlus512 = add i64 %A, 512\n"
2379                 "  %c = icmp ugt i64 %APlus512, 523\n"
2380                 "  call void @llvm.assume(i1 %c)\n"
2381                 "  ret void\n"
2382                 "}\n"
2383                 "declare void @llvm.assume(i1)\n");
2384   AssumptionCache AC(*F);
2385   KnownBits Known = computeKnownBits(A, M->getDataLayout(), /* Depth */ 0, &AC,
2386                                      F->front().getTerminator());
2387   EXPECT_EQ(Known.Zero.getZExtValue(), ~(65536llu - 1));
2388   EXPECT_EQ(Known.One.getZExtValue(), 0u);
2389   Instruction &APlus512 = findInstructionByName(F, "APlus512");
2390   Known = computeKnownBits(&APlus512, M->getDataLayout(), /* Depth */ 0, &AC,
2391                            F->front().getTerminator());
2392   // We know of one less zero because 512 may have produced a 1 that
2393   // got carried all the way to the first trailing zero.
2394   EXPECT_EQ(Known.Zero.getZExtValue(), (~(65536llu - 1)) << 1);
2395   EXPECT_EQ(Known.One.getZExtValue(), 0u);
2396   // The known range is not precise given computeKnownBits works
2397   // with the masks of zeros and ones, not the ranges.
2398   EXPECT_EQ(Known.getMinValue(), 0u);
2399   EXPECT_EQ(Known.getMaxValue(), 131071);
2400 }
2401 
2402 TEST_F(ComputeKnownBitsTest, ComputeKnownBitsUnknownVScale) {
2403   Module M("", Context);
2404   IRBuilder<> Builder(Context);
2405   Function *TheFn =
2406       Intrinsic::getDeclaration(&M, Intrinsic::vscale, {Builder.getInt32Ty()});
2407   CallInst *CI = Builder.CreateCall(TheFn, {}, {}, "");
2408 
2409   KnownBits Known = computeKnownBits(CI, M.getDataLayout(), /* Depth */ 0);
2410   // There is no parent function so we cannot look up the vscale_range
2411   // attribute to determine the number of bits.
2412   EXPECT_EQ(Known.One.getZExtValue(), 0u);
2413   EXPECT_EQ(Known.Zero.getZExtValue(), 0u);
2414 
2415   BasicBlock *BB = BasicBlock::Create(Context);
2416   CI->insertInto(BB, BB->end());
2417   Known = computeKnownBits(CI, M.getDataLayout(), /* Depth */ 0);
2418   // There is no parent function so we cannot look up the vscale_range
2419   // attribute to determine the number of bits.
2420   EXPECT_EQ(Known.One.getZExtValue(), 0u);
2421   EXPECT_EQ(Known.Zero.getZExtValue(), 0u);
2422 
2423   CI->removeFromParent();
2424   delete CI;
2425   delete BB;
2426 }
2427 
2428 // 512 + [32, 64) doesn't produce overlapping bits.
2429 // Make sure we get all the individual bits properly.
2430 TEST_F(ComputeKnownBitsTest, ComputeKnownBitsAddWithRangeNoOverlap) {
2431   parseAssembly("define void @test(ptr %p) {\n"
2432                 "  %A = load i64, ptr %p, !range !{i64 32, i64 64}\n"
2433                 "  %APlus512 = add i64 %A, 512\n"
2434                 "  %c = icmp ugt i64 %APlus512, 523\n"
2435                 "  call void @llvm.assume(i1 %c)\n"
2436                 "  ret void\n"
2437                 "}\n"
2438                 "declare void @llvm.assume(i1)\n");
2439   AssumptionCache AC(*F);
2440   KnownBits Known = computeKnownBits(A, M->getDataLayout(), /* Depth */ 0, &AC,
2441                                      F->front().getTerminator());
2442   EXPECT_EQ(Known.Zero.getZExtValue(), ~(64llu - 1));
2443   EXPECT_EQ(Known.One.getZExtValue(), 32u);
2444   Instruction &APlus512 = findInstructionByName(F, "APlus512");
2445   Known = computeKnownBits(&APlus512, M->getDataLayout(), /* Depth */ 0, &AC,
2446                            F->front().getTerminator());
2447   EXPECT_EQ(Known.Zero.getZExtValue(), ~512llu & ~(64llu - 1));
2448   EXPECT_EQ(Known.One.getZExtValue(), 512u | 32u);
2449   // The known range is not precise given computeKnownBits works
2450   // with the masks of zeros and ones, not the ranges.
2451   EXPECT_EQ(Known.getMinValue(), 544);
2452   EXPECT_EQ(Known.getMaxValue(), 575);
2453 }
2454 
2455 TEST_F(ComputeKnownBitsTest, ComputeKnownBitsGEPWithRange) {
2456   parseAssembly(
2457       "define void @test(ptr %p) {\n"
2458       "  %A = load i64, ptr %p, !range !{i64 64, i64 65536}\n"
2459       "  %APtr = inttoptr i64 %A to float*"
2460       "  %APtrPlus512 = getelementptr float, float* %APtr, i32 128\n"
2461       "  %c = icmp ugt float* %APtrPlus512, inttoptr (i32 523 to float*)\n"
2462       "  call void @llvm.assume(i1 %c)\n"
2463       "  ret void\n"
2464       "}\n"
2465       "declare void @llvm.assume(i1)\n");
2466   AssumptionCache AC(*F);
2467   KnownBits Known = computeKnownBits(A, M->getDataLayout(), /* Depth */ 0, &AC,
2468                                      F->front().getTerminator());
2469   EXPECT_EQ(Known.Zero.getZExtValue(), ~(65536llu - 1));
2470   EXPECT_EQ(Known.One.getZExtValue(), 0u);
2471   Instruction &APtrPlus512 = findInstructionByName(F, "APtrPlus512");
2472   Known = computeKnownBits(&APtrPlus512, M->getDataLayout(), /* Depth */ 0, &AC,
2473                            F->front().getTerminator());
2474   // We know of one less zero because 512 may have produced a 1 that
2475   // got carried all the way to the first trailing zero.
2476   EXPECT_EQ(Known.Zero.getZExtValue(), ~(65536llu - 1) << 1);
2477   EXPECT_EQ(Known.One.getZExtValue(), 0u);
2478   // The known range is not precise given computeKnownBits works
2479   // with the masks of zeros and ones, not the ranges.
2480   EXPECT_EQ(Known.getMinValue(), 0u);
2481   EXPECT_EQ(Known.getMaxValue(), 131071);
2482 }
2483 
2484 // 4*128 + [32, 64) doesn't produce overlapping bits.
2485 // Make sure we get all the individual bits properly.
2486 // This test is useful to check that we account for the scaling factor
2487 // in the gep. Indeed, gep float, [32,64), 128 is not 128 + [32,64).
2488 TEST_F(ComputeKnownBitsTest, ComputeKnownBitsGEPWithRangeNoOverlap) {
2489   parseAssembly(
2490       "define void @test(ptr %p) {\n"
2491       "  %A = load i64, ptr %p, !range !{i64 32, i64 64}\n"
2492       "  %APtr = inttoptr i64 %A to float*"
2493       "  %APtrPlus512 = getelementptr float, float* %APtr, i32 128\n"
2494       "  %c = icmp ugt float* %APtrPlus512, inttoptr (i32 523 to float*)\n"
2495       "  call void @llvm.assume(i1 %c)\n"
2496       "  ret void\n"
2497       "}\n"
2498       "declare void @llvm.assume(i1)\n");
2499   AssumptionCache AC(*F);
2500   KnownBits Known = computeKnownBits(A, M->getDataLayout(), /* Depth */ 0, &AC,
2501                                      F->front().getTerminator());
2502   EXPECT_EQ(Known.Zero.getZExtValue(), ~(64llu - 1));
2503   EXPECT_EQ(Known.One.getZExtValue(), 32u);
2504   Instruction &APtrPlus512 = findInstructionByName(F, "APtrPlus512");
2505   Known = computeKnownBits(&APtrPlus512, M->getDataLayout(), /* Depth */ 0, &AC,
2506                            F->front().getTerminator());
2507   EXPECT_EQ(Known.Zero.getZExtValue(), ~512llu & ~(64llu - 1));
2508   EXPECT_EQ(Known.One.getZExtValue(), 512u | 32u);
2509   // The known range is not precise given computeKnownBits works
2510   // with the masks of zeros and ones, not the ranges.
2511   EXPECT_EQ(Known.getMinValue(), 544);
2512   EXPECT_EQ(Known.getMaxValue(), 575);
2513 }
2514 
2515 TEST_F(ComputeKnownBitsTest, ComputeKnownBitsAbsoluteSymbol) {
2516   auto M = parseModule(R"(
2517     @absolute_0_255 = external global [128 x i32], align 1, !absolute_symbol !0
2518     @absolute_0_256 = external global [128 x i32], align 1, !absolute_symbol !1
2519     @absolute_256_512 = external global [128 x i32], align 1, !absolute_symbol !2
2520     @absolute_0_neg1 = external global [128 x i32], align 1, !absolute_symbol !3
2521     @absolute_neg32_32 = external global [128 x i32], align 1, !absolute_symbol !4
2522     @absolute_neg32_33 = external global [128 x i32], align 1, !absolute_symbol !5
2523     @absolute_neg64_neg32 = external global [128 x i32], align 1, !absolute_symbol !6
2524     @absolute_0_256_align8 = external global [128 x i32], align 8, !absolute_symbol !1
2525 
2526     !0 = !{i64 0, i64 255}
2527     !1 = !{i64 0, i64 256}
2528     !2 = !{i64 256, i64 512}
2529     !3 = !{i64 0, i64 -1}
2530     !4 = !{i64 -32, i64 32}
2531     !5 = !{i64 -32, i64 33}
2532     !6 = !{i64 -64, i64 -32}
2533   )");
2534 
2535   GlobalValue *Absolute_0_255 = M->getNamedValue("absolute_0_255");
2536   GlobalValue *Absolute_0_256 = M->getNamedValue("absolute_0_256");
2537   GlobalValue *Absolute_256_512 = M->getNamedValue("absolute_256_512");
2538   GlobalValue *Absolute_0_Neg1 = M->getNamedValue("absolute_0_neg1");
2539   GlobalValue *Absolute_Neg32_32 = M->getNamedValue("absolute_neg32_32");
2540   GlobalValue *Absolute_Neg32_33 = M->getNamedValue("absolute_neg32_33");
2541   GlobalValue *Absolute_Neg64_Neg32 = M->getNamedValue("absolute_neg64_neg32");
2542   GlobalValue *Absolute_0_256_Align8 =
2543       M->getNamedValue("absolute_0_256_align8");
2544 
2545   KnownBits Known_0_255 = computeKnownBits(Absolute_0_255, M->getDataLayout());
2546   EXPECT_EQ(64u - 8u, Known_0_255.countMinLeadingZeros());
2547   EXPECT_EQ(0u, Known_0_255.countMinTrailingZeros());
2548   EXPECT_EQ(0u, Known_0_255.countMinLeadingOnes());
2549   EXPECT_EQ(0u, Known_0_255.countMinTrailingOnes());
2550 
2551   KnownBits Known_0_256 = computeKnownBits(Absolute_0_256, M->getDataLayout());
2552   EXPECT_EQ(64u - 8u, Known_0_256.countMinLeadingZeros());
2553   EXPECT_EQ(0u, Known_0_256.countMinTrailingZeros());
2554   EXPECT_EQ(0u, Known_0_256.countMinLeadingOnes());
2555   EXPECT_EQ(0u, Known_0_256.countMinTrailingOnes());
2556 
2557   KnownBits Known_256_512 =
2558       computeKnownBits(Absolute_256_512, M->getDataLayout());
2559   EXPECT_EQ(64u - 8u, Known_0_255.countMinLeadingZeros());
2560   EXPECT_EQ(0u, Known_0_255.countMinTrailingZeros());
2561   EXPECT_EQ(0u, Known_0_255.countMinLeadingOnes());
2562   EXPECT_EQ(0u, Known_0_255.countMinTrailingOnes());
2563 
2564   KnownBits Known_0_Neg1 =
2565       computeKnownBits(Absolute_0_Neg1, M->getDataLayout());
2566   EXPECT_EQ(0u, Known_0_Neg1.countMinLeadingZeros());
2567   EXPECT_EQ(0u, Known_0_Neg1.countMinTrailingZeros());
2568   EXPECT_EQ(0u, Known_0_Neg1.countMinLeadingOnes());
2569   EXPECT_EQ(0u, Known_0_Neg1.countMinTrailingOnes());
2570 
2571   KnownBits Known_Neg32_32 =
2572       computeKnownBits(Absolute_Neg32_32, M->getDataLayout());
2573   EXPECT_EQ(0u, Known_Neg32_32.countMinLeadingZeros());
2574   EXPECT_EQ(0u, Known_Neg32_32.countMinTrailingZeros());
2575   EXPECT_EQ(0u, Known_Neg32_32.countMinLeadingOnes());
2576   EXPECT_EQ(0u, Known_Neg32_32.countMinTrailingOnes());
2577   EXPECT_EQ(1u, Known_Neg32_32.countMinSignBits());
2578 
2579   KnownBits Known_Neg32_33 =
2580       computeKnownBits(Absolute_Neg32_33, M->getDataLayout());
2581   EXPECT_EQ(0u, Known_Neg32_33.countMinLeadingZeros());
2582   EXPECT_EQ(0u, Known_Neg32_33.countMinTrailingZeros());
2583   EXPECT_EQ(0u, Known_Neg32_33.countMinLeadingOnes());
2584   EXPECT_EQ(0u, Known_Neg32_33.countMinTrailingOnes());
2585   EXPECT_EQ(1u, Known_Neg32_33.countMinSignBits());
2586 
2587   KnownBits Known_Neg32_Neg32 =
2588       computeKnownBits(Absolute_Neg64_Neg32, M->getDataLayout());
2589   EXPECT_EQ(0u, Known_Neg32_Neg32.countMinLeadingZeros());
2590   EXPECT_EQ(0u, Known_Neg32_Neg32.countMinTrailingZeros());
2591   EXPECT_EQ(58u, Known_Neg32_Neg32.countMinLeadingOnes());
2592   EXPECT_EQ(0u, Known_Neg32_Neg32.countMinTrailingOnes());
2593   EXPECT_EQ(58u, Known_Neg32_Neg32.countMinSignBits());
2594 
2595   KnownBits Known_0_256_Align8 =
2596       computeKnownBits(Absolute_0_256_Align8, M->getDataLayout());
2597   EXPECT_EQ(64u - 8u, Known_0_256_Align8.countMinLeadingZeros());
2598   EXPECT_EQ(3u, Known_0_256_Align8.countMinTrailingZeros());
2599   EXPECT_EQ(0u, Known_0_256_Align8.countMinLeadingOnes());
2600   EXPECT_EQ(0u, Known_0_256_Align8.countMinTrailingOnes());
2601 }
2602 
2603 TEST_F(ValueTrackingTest, HaveNoCommonBitsSet) {
2604   {
2605     // Check for an inverted mask: (X & ~M) op (Y & M).
2606     auto M = parseModule(R"(
2607   define i32 @test(i32 %X, i32 %Y, i32 noundef %M) {
2608     %1 = xor i32 %M, -1
2609     %LHS = and i32 %1, %X
2610     %RHS = and i32 %Y, %M
2611     %Ret = add i32 %LHS, %RHS
2612     ret i32 %Ret
2613   })");
2614 
2615     auto *F = M->getFunction("test");
2616     auto *LHS = findInstructionByNameOrNull(F, "LHS");
2617     auto *RHS = findInstructionByNameOrNull(F, "RHS");
2618 
2619     const DataLayout &DL = M->getDataLayout();
2620     EXPECT_TRUE(haveNoCommonBitsSet(LHS, RHS, DL));
2621     EXPECT_TRUE(haveNoCommonBitsSet(RHS, LHS, DL));
2622   }
2623   {
2624     // Check for (A & B) and ~(A | B)
2625     auto M = parseModule(R"(
2626   define void @test(i32 noundef %A, i32 noundef %B) {
2627     %LHS = and i32 %A, %B
2628     %or = or i32 %A, %B
2629     %RHS = xor i32 %or, -1
2630 
2631     %LHS2 = and i32 %B, %A
2632     %or2 = or i32 %A, %B
2633     %RHS2 = xor i32 %or2, -1
2634 
2635     ret void
2636   })");
2637 
2638     auto *F = M->getFunction("test");
2639     const DataLayout &DL = M->getDataLayout();
2640 
2641     auto *LHS = findInstructionByNameOrNull(F, "LHS");
2642     auto *RHS = findInstructionByNameOrNull(F, "RHS");
2643     EXPECT_TRUE(haveNoCommonBitsSet(LHS, RHS, DL));
2644     EXPECT_TRUE(haveNoCommonBitsSet(RHS, LHS, DL));
2645 
2646     auto *LHS2 = findInstructionByNameOrNull(F, "LHS2");
2647     auto *RHS2 = findInstructionByNameOrNull(F, "RHS2");
2648     EXPECT_TRUE(haveNoCommonBitsSet(LHS2, RHS2, DL));
2649     EXPECT_TRUE(haveNoCommonBitsSet(RHS2, LHS2, DL));
2650   }
2651   {
2652     // Check for (A & B) and ~(A | B) in vector version
2653     auto M = parseModule(R"(
2654   define void @test(<2 x i32> noundef %A, <2 x i32> noundef %B) {
2655     %LHS = and <2 x i32> %A, %B
2656     %or = or <2 x i32> %A, %B
2657     %RHS = xor <2 x i32> %or, <i32 -1, i32 -1>
2658 
2659     %LHS2 = and <2 x i32> %B, %A
2660     %or2 = or <2 x i32> %A, %B
2661     %RHS2 = xor <2 x i32> %or2, <i32 -1, i32 -1>
2662 
2663     ret void
2664   })");
2665 
2666     auto *F = M->getFunction("test");
2667     const DataLayout &DL = M->getDataLayout();
2668 
2669     auto *LHS = findInstructionByNameOrNull(F, "LHS");
2670     auto *RHS = findInstructionByNameOrNull(F, "RHS");
2671     EXPECT_TRUE(haveNoCommonBitsSet(LHS, RHS, DL));
2672     EXPECT_TRUE(haveNoCommonBitsSet(RHS, LHS, DL));
2673 
2674     auto *LHS2 = findInstructionByNameOrNull(F, "LHS2");
2675     auto *RHS2 = findInstructionByNameOrNull(F, "RHS2");
2676     EXPECT_TRUE(haveNoCommonBitsSet(LHS2, RHS2, DL));
2677     EXPECT_TRUE(haveNoCommonBitsSet(RHS2, LHS2, DL));
2678   }
2679 }
2680 
2681 class IsBytewiseValueTest : public ValueTrackingTest,
2682                             public ::testing::WithParamInterface<
2683                                 std::pair<const char *, const char *>> {
2684 protected:
2685 };
2686 
2687 const std::pair<const char *, const char *> IsBytewiseValueTests[] = {
2688     {
2689         "i8 0",
2690         "i48* null",
2691     },
2692     {
2693         "i8 undef",
2694         "i48* undef",
2695     },
2696     {
2697         "i8 0",
2698         "i8 zeroinitializer",
2699     },
2700     {
2701         "i8 0",
2702         "i8 0",
2703     },
2704     {
2705         "i8 -86",
2706         "i8 -86",
2707     },
2708     {
2709         "i8 -1",
2710         "i8 -1",
2711     },
2712     {
2713         "i8 undef",
2714         "i16 undef",
2715     },
2716     {
2717         "i8 0",
2718         "i16 0",
2719     },
2720     {
2721         "",
2722         "i16 7",
2723     },
2724     {
2725         "i8 -86",
2726         "i16 -21846",
2727     },
2728     {
2729         "i8 -1",
2730         "i16 -1",
2731     },
2732     {
2733         "i8 0",
2734         "i48 0",
2735     },
2736     {
2737         "i8 -1",
2738         "i48 -1",
2739     },
2740     {
2741         "i8 0",
2742         "i49 0",
2743     },
2744     {
2745         "",
2746         "i49 -1",
2747     },
2748     {
2749         "i8 0",
2750         "half 0xH0000",
2751     },
2752     {
2753         "i8 -85",
2754         "half 0xHABAB",
2755     },
2756     {
2757         "i8 0",
2758         "float 0.0",
2759     },
2760     {
2761         "i8 -1",
2762         "float 0xFFFFFFFFE0000000",
2763     },
2764     {
2765         "i8 0",
2766         "double 0.0",
2767     },
2768     {
2769         "i8 -15",
2770         "double 0xF1F1F1F1F1F1F1F1",
2771     },
2772     {
2773         "i8 undef",
2774         "i16* undef",
2775     },
2776     {
2777         "i8 0",
2778         "i16* inttoptr (i64 0 to i16*)",
2779     },
2780     {
2781         "i8 -1",
2782         "i16* inttoptr (i64 -1 to i16*)",
2783     },
2784     {
2785         "i8 -86",
2786         "i16* inttoptr (i64 -6148914691236517206 to i16*)",
2787     },
2788     {
2789         "",
2790         "i16* inttoptr (i48 -1 to i16*)",
2791     },
2792     {
2793         "i8 -1",
2794         "i16* inttoptr (i96 -1 to i16*)",
2795     },
2796     {
2797         "i8 undef",
2798         "[0 x i8] zeroinitializer",
2799     },
2800     {
2801         "i8 undef",
2802         "[0 x i8] undef",
2803     },
2804     {
2805         "i8 undef",
2806         "[5 x [0 x i8]] zeroinitializer",
2807     },
2808     {
2809         "i8 undef",
2810         "[5 x [0 x i8]] undef",
2811     },
2812     {
2813         "i8 0",
2814         "[6 x i8] zeroinitializer",
2815     },
2816     {
2817         "i8 undef",
2818         "[6 x i8] undef",
2819     },
2820     {
2821         "i8 1",
2822         "[5 x i8] [i8 1, i8 1, i8 1, i8 1, i8 1]",
2823     },
2824     {
2825         "",
2826         "[5 x i64] [i64 1, i64 1, i64 1, i64 1, i64 1]",
2827     },
2828     {
2829         "i8 -1",
2830         "[5 x i64] [i64 -1, i64 -1, i64 -1, i64 -1, i64 -1]",
2831     },
2832     {
2833         "",
2834         "[4 x i8] [i8 1, i8 2, i8 1, i8 1]",
2835     },
2836     {
2837         "i8 1",
2838         "[4 x i8] [i8 1, i8 undef, i8 1, i8 1]",
2839     },
2840     {
2841         "i8 0",
2842         "<6 x i8> zeroinitializer",
2843     },
2844     {
2845         "i8 undef",
2846         "<6 x i8> undef",
2847     },
2848     {
2849         "i8 1",
2850         "<5 x i8> <i8 1, i8 1, i8 1, i8 1, i8 1>",
2851     },
2852     {
2853         "",
2854         "<5 x i64> <i64 1, i64 1, i64 1, i64 1, i64 1>",
2855     },
2856     {
2857         "i8 -1",
2858         "<5 x i64> <i64 -1, i64 -1, i64 -1, i64 -1, i64 -1>",
2859     },
2860     {
2861         "",
2862         "<4 x i8> <i8 1, i8 1, i8 2, i8 1>",
2863     },
2864     {
2865         "i8 5",
2866         "<2 x i8> < i8 5, i8 undef >",
2867     },
2868     {
2869         "i8 0",
2870         "[2 x [2 x i16]] zeroinitializer",
2871     },
2872     {
2873         "i8 undef",
2874         "[2 x [2 x i16]] undef",
2875     },
2876     {
2877         "i8 -86",
2878         "[2 x [2 x i16]] [[2 x i16] [i16 -21846, i16 -21846], "
2879         "[2 x i16] [i16 -21846, i16 -21846]]",
2880     },
2881     {
2882         "",
2883         "[2 x [2 x i16]] [[2 x i16] [i16 -21846, i16 -21846], "
2884         "[2 x i16] [i16 -21836, i16 -21846]]",
2885     },
2886     {
2887         "i8 undef",
2888         "{ } zeroinitializer",
2889     },
2890     {
2891         "i8 undef",
2892         "{ } undef",
2893     },
2894     {
2895         "i8 undef",
2896         "{ {}, {} } zeroinitializer",
2897     },
2898     {
2899         "i8 undef",
2900         "{ {}, {} } undef",
2901     },
2902     {
2903         "i8 0",
2904         "{i8, i64, i16*} zeroinitializer",
2905     },
2906     {
2907         "i8 undef",
2908         "{i8, i64, i16*} undef",
2909     },
2910     {
2911         "i8 -86",
2912         "{i8, i64, i16*} {i8 -86, i64 -6148914691236517206, i16* undef}",
2913     },
2914     {
2915         "",
2916         "{i8, i64, i16*} {i8 86, i64 -6148914691236517206, i16* undef}",
2917     },
2918 };
2919 
2920 INSTANTIATE_TEST_SUITE_P(IsBytewiseValueParamTests, IsBytewiseValueTest,
2921                          ::testing::ValuesIn(IsBytewiseValueTests));
2922 
2923 TEST_P(IsBytewiseValueTest, IsBytewiseValue) {
2924   auto M = parseModule(std::string("@test = global ") + GetParam().second);
2925   GlobalVariable *GV = dyn_cast<GlobalVariable>(M->getNamedValue("test"));
2926   Value *Actual = isBytewiseValue(GV->getInitializer(), M->getDataLayout());
2927   std::string Buff;
2928   raw_string_ostream S(Buff);
2929   if (Actual)
2930     S << *Actual;
2931   EXPECT_EQ(GetParam().first, S.str());
2932 }
2933 
2934 TEST_F(ValueTrackingTest, ComputeConstantRange) {
2935   {
2936     // Assumptions:
2937     //  * stride >= 5
2938     //  * stride < 10
2939     //
2940     // stride = [5, 10)
2941     auto M = parseModule(R"(
2942   declare void @llvm.assume(i1)
2943 
2944   define i32 @test(i32 %stride) {
2945     %gt = icmp uge i32 %stride, 5
2946     call void @llvm.assume(i1 %gt)
2947     %lt = icmp ult i32 %stride, 10
2948     call void @llvm.assume(i1 %lt)
2949     %stride.plus.one = add nsw nuw i32 %stride, 1
2950     ret i32 %stride.plus.one
2951   })");
2952     Function *F = M->getFunction("test");
2953 
2954     AssumptionCache AC(*F);
2955     Value *Stride = &*F->arg_begin();
2956     ConstantRange CR1 = computeConstantRange(Stride, false, true, &AC, nullptr);
2957     EXPECT_TRUE(CR1.isFullSet());
2958 
2959     Instruction *I = &findInstructionByName(F, "stride.plus.one");
2960     ConstantRange CR2 = computeConstantRange(Stride, false, true, &AC, I);
2961     EXPECT_EQ(5, CR2.getLower());
2962     EXPECT_EQ(10, CR2.getUpper());
2963   }
2964 
2965   {
2966     // Assumptions:
2967     //  * stride >= 5
2968     //  * stride < 200
2969     //  * stride == 99
2970     //
2971     // stride = [99, 100)
2972     auto M = parseModule(R"(
2973   declare void @llvm.assume(i1)
2974 
2975   define i32 @test(i32 %stride) {
2976     %gt = icmp uge i32 %stride, 5
2977     call void @llvm.assume(i1 %gt)
2978     %lt = icmp ult i32 %stride, 200
2979     call void @llvm.assume(i1 %lt)
2980     %eq = icmp eq i32 %stride, 99
2981     call void @llvm.assume(i1 %eq)
2982     %stride.plus.one = add nsw nuw i32 %stride, 1
2983     ret i32 %stride.plus.one
2984   })");
2985     Function *F = M->getFunction("test");
2986 
2987     AssumptionCache AC(*F);
2988     Value *Stride = &*F->arg_begin();
2989     Instruction *I = &findInstructionByName(F, "stride.plus.one");
2990     ConstantRange CR = computeConstantRange(Stride, false, true, &AC, I);
2991     EXPECT_EQ(99, *CR.getSingleElement());
2992   }
2993 
2994   {
2995     // Assumptions:
2996     //  * stride >= 5
2997     //  * stride >= 50
2998     //  * stride < 100
2999     //  * stride < 200
3000     //
3001     // stride = [50, 100)
3002     auto M = parseModule(R"(
3003   declare void @llvm.assume(i1)
3004 
3005   define i32 @test(i32 %stride, i1 %cond) {
3006     %gt = icmp uge i32 %stride, 5
3007     call void @llvm.assume(i1 %gt)
3008     %gt.2 = icmp uge i32 %stride, 50
3009     call void @llvm.assume(i1 %gt.2)
3010     br i1 %cond, label %bb1, label %bb2
3011 
3012   bb1:
3013     %lt = icmp ult i32 %stride, 200
3014     call void @llvm.assume(i1 %lt)
3015     %lt.2 = icmp ult i32 %stride, 100
3016     call void @llvm.assume(i1 %lt.2)
3017     %stride.plus.one = add nsw nuw i32 %stride, 1
3018     ret i32 %stride.plus.one
3019 
3020   bb2:
3021     ret i32 0
3022   })");
3023     Function *F = M->getFunction("test");
3024 
3025     AssumptionCache AC(*F);
3026     Value *Stride = &*F->arg_begin();
3027     Instruction *GT2 = &findInstructionByName(F, "gt.2");
3028     ConstantRange CR = computeConstantRange(Stride, false, true, &AC, GT2);
3029     EXPECT_EQ(5, CR.getLower());
3030     EXPECT_EQ(0, CR.getUpper());
3031 
3032     Instruction *I = &findInstructionByName(F, "stride.plus.one");
3033     ConstantRange CR2 = computeConstantRange(Stride, false, true, &AC, I);
3034     EXPECT_EQ(50, CR2.getLower());
3035     EXPECT_EQ(100, CR2.getUpper());
3036   }
3037 
3038   {
3039     // Assumptions:
3040     //  * stride > 5
3041     //  * stride < 5
3042     //
3043     // stride = empty range, as the assumptions contradict each other.
3044     auto M = parseModule(R"(
3045   declare void @llvm.assume(i1)
3046 
3047   define i32 @test(i32 %stride, i1 %cond) {
3048     %gt = icmp ugt i32 %stride, 5
3049     call void @llvm.assume(i1 %gt)
3050     %lt = icmp ult i32 %stride, 5
3051     call void @llvm.assume(i1 %lt)
3052     %stride.plus.one = add nsw nuw i32 %stride, 1
3053     ret i32 %stride.plus.one
3054   })");
3055     Function *F = M->getFunction("test");
3056 
3057     AssumptionCache AC(*F);
3058     Value *Stride = &*F->arg_begin();
3059 
3060     Instruction *I = &findInstructionByName(F, "stride.plus.one");
3061     ConstantRange CR = computeConstantRange(Stride, false, true, &AC, I);
3062     EXPECT_TRUE(CR.isEmptySet());
3063   }
3064 
3065   {
3066     // Assumptions:
3067     //  * x.1 >= 5
3068     //  * x.2 < x.1
3069     //
3070     // stride = [0, -1)
3071     auto M = parseModule(R"(
3072   declare void @llvm.assume(i1)
3073 
3074   define i32 @test(i32 %x.1, i32 %x.2) {
3075     %gt = icmp uge i32 %x.1, 5
3076     call void @llvm.assume(i1 %gt)
3077     %lt = icmp ult i32 %x.2, %x.1
3078     call void @llvm.assume(i1 %lt)
3079     %stride.plus.one = add nsw nuw i32 %x.1, 1
3080     ret i32 %stride.plus.one
3081   })");
3082     Function *F = M->getFunction("test");
3083 
3084     AssumptionCache AC(*F);
3085     Value *X1 = &*(F->arg_begin());
3086     Value *X2 = &*std::next(F->arg_begin());
3087 
3088     Instruction *I = &findInstructionByName(F, "stride.plus.one");
3089     ConstantRange CR1 = computeConstantRange(X1, false, true, &AC, I);
3090     ConstantRange CR2 = computeConstantRange(X2, false, true, &AC, I);
3091 
3092     EXPECT_EQ(5, CR1.getLower());
3093     EXPECT_EQ(0, CR1.getUpper());
3094 
3095     EXPECT_EQ(0, CR2.getLower());
3096     EXPECT_EQ(0xffffffff, CR2.getUpper());
3097 
3098     // Check the depth cutoff results in a conservative result (full set) by
3099     // passing Depth == MaxDepth == 6.
3100     ConstantRange CR3 = computeConstantRange(X2, false, true, &AC, I, nullptr, 6);
3101     EXPECT_TRUE(CR3.isFullSet());
3102   }
3103   {
3104     // Assumptions:
3105     //  * x.2 <= x.1
3106     auto M = parseModule(R"(
3107   declare void @llvm.assume(i1)
3108 
3109   define i32 @test(i32 %x.1, i32 %x.2) {
3110     %lt = icmp ule i32 %x.2, %x.1
3111     call void @llvm.assume(i1 %lt)
3112     %stride.plus.one = add nsw nuw i32 %x.1, 1
3113     ret i32 %stride.plus.one
3114   })");
3115     Function *F = M->getFunction("test");
3116 
3117     AssumptionCache AC(*F);
3118     Value *X2 = &*std::next(F->arg_begin());
3119 
3120     Instruction *I = &findInstructionByName(F, "stride.plus.one");
3121     ConstantRange CR1 = computeConstantRange(X2, false, true, &AC, I);
3122     // If we don't know the value of x.2, we don't know the value of x.1.
3123     EXPECT_TRUE(CR1.isFullSet());
3124   }
3125 }
3126 
3127 struct FindAllocaForValueTestParams {
3128   const char *IR;
3129   bool AnyOffsetResult;
3130   bool ZeroOffsetResult;
3131 };
3132 
3133 class FindAllocaForValueTest
3134     : public ValueTrackingTest,
3135       public ::testing::WithParamInterface<FindAllocaForValueTestParams> {
3136 protected:
3137 };
3138 
3139 const FindAllocaForValueTestParams FindAllocaForValueTests[] = {
3140     {R"(
3141       define void @test() {
3142         %a = alloca i64
3143         %r = bitcast ptr %a to ptr
3144         ret void
3145       })",
3146      true, true},
3147 
3148     {R"(
3149       define void @test() {
3150         %a = alloca i32
3151         %r = getelementptr i32, ptr %a, i32 1
3152         ret void
3153       })",
3154      true, false},
3155 
3156     {R"(
3157       define void @test() {
3158         %a = alloca i32
3159         %r = getelementptr i32, ptr %a, i32 0
3160         ret void
3161       })",
3162      true, true},
3163 
3164     {R"(
3165       define void @test(i1 %cond) {
3166       entry:
3167         %a = alloca i32
3168         br label %bb1
3169 
3170       bb1:
3171         %r = phi ptr [ %a, %entry ], [ %r, %bb1 ]
3172         br i1 %cond, label %bb1, label %exit
3173 
3174       exit:
3175         ret void
3176       })",
3177      true, true},
3178 
3179     {R"(
3180       define void @test(i1 %cond) {
3181         %a = alloca i32
3182         %r = select i1 %cond, ptr %a, ptr %a
3183         ret void
3184       })",
3185      true, true},
3186 
3187     {R"(
3188       define void @test(i1 %cond) {
3189         %a = alloca i32
3190         %b = alloca i32
3191         %r = select i1 %cond, ptr %a, ptr %b
3192         ret void
3193       })",
3194      false, false},
3195 
3196     {R"(
3197       define void @test(i1 %cond) {
3198       entry:
3199         %a = alloca i64
3200         %a32 = bitcast ptr %a to ptr
3201         br label %bb1
3202 
3203       bb1:
3204         %x = phi ptr [ %a32, %entry ], [ %x, %bb1 ]
3205         %r = getelementptr i32, ptr %x, i32 1
3206         br i1 %cond, label %bb1, label %exit
3207 
3208       exit:
3209         ret void
3210       })",
3211      true, false},
3212 
3213     {R"(
3214       define void @test(i1 %cond) {
3215       entry:
3216         %a = alloca i64
3217         %a32 = bitcast ptr %a to ptr
3218         br label %bb1
3219 
3220       bb1:
3221         %x = phi ptr [ %a32, %entry ], [ %r, %bb1 ]
3222         %r = getelementptr i32, ptr %x, i32 1
3223         br i1 %cond, label %bb1, label %exit
3224 
3225       exit:
3226         ret void
3227       })",
3228      true, false},
3229 
3230     {R"(
3231       define void @test(i1 %cond, ptr %a) {
3232       entry:
3233         %r = bitcast ptr %a to ptr
3234         ret void
3235       })",
3236      false, false},
3237 
3238     {R"(
3239       define void @test(i1 %cond) {
3240       entry:
3241         %a = alloca i32
3242         %b = alloca i32
3243         br label %bb1
3244 
3245       bb1:
3246         %r = phi ptr [ %a, %entry ], [ %b, %bb1 ]
3247         br i1 %cond, label %bb1, label %exit
3248 
3249       exit:
3250         ret void
3251       })",
3252      false, false},
3253     {R"(
3254       declare ptr @retptr(ptr returned)
3255       define void @test(i1 %cond) {
3256         %a = alloca i32
3257         %r = call ptr @retptr(ptr %a)
3258         ret void
3259       })",
3260      true, true},
3261     {R"(
3262       declare ptr @fun(ptr)
3263       define void @test(i1 %cond) {
3264         %a = alloca i32
3265         %r = call ptr @fun(ptr %a)
3266         ret void
3267       })",
3268      false, false},
3269 };
3270 
3271 TEST_P(FindAllocaForValueTest, findAllocaForValue) {
3272   auto M = parseModule(GetParam().IR);
3273   Function *F = M->getFunction("test");
3274   Instruction *I = &findInstructionByName(F, "r");
3275   const AllocaInst *AI = findAllocaForValue(I);
3276   EXPECT_EQ(!!AI, GetParam().AnyOffsetResult);
3277 }
3278 
3279 TEST_P(FindAllocaForValueTest, findAllocaForValueZeroOffset) {
3280   auto M = parseModule(GetParam().IR);
3281   Function *F = M->getFunction("test");
3282   Instruction *I = &findInstructionByName(F, "r");
3283   const AllocaInst *AI = findAllocaForValue(I, true);
3284   EXPECT_EQ(!!AI, GetParam().ZeroOffsetResult);
3285 }
3286 
3287 INSTANTIATE_TEST_SUITE_P(FindAllocaForValueTest, FindAllocaForValueTest,
3288                          ::testing::ValuesIn(FindAllocaForValueTests));
3289