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()), 1u); 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, CannotBeOrderedLessThanZero) { 1634 parseAssembly("define float @test(float %arg) {\n" 1635 " %A = fmul float %arg, %arg" 1636 " ret float %A\n" 1637 "}\n"); 1638 1639 Type *FPTy = Type::getDoubleTy(M->getContext()); 1640 const DataLayout &DL = M->getDataLayout(); 1641 1642 EXPECT_TRUE( 1643 computeKnownFPClass(ConstantFP::getZero(FPTy, /*Negative=*/false), DL) 1644 .cannotBeOrderedLessThanZero()); 1645 EXPECT_TRUE( 1646 computeKnownFPClass(ConstantFP::getZero(FPTy, /*Negative=*/true), DL) 1647 .cannotBeOrderedLessThanZero()); 1648 1649 EXPECT_TRUE(computeKnownFPClass(ConstantFP::getInfinity(FPTy, false), DL) 1650 .cannotBeOrderedLessThanZero()); 1651 EXPECT_FALSE(computeKnownFPClass(ConstantFP::getInfinity(FPTy, true), DL) 1652 .cannotBeOrderedLessThanZero()); 1653 1654 EXPECT_TRUE(computeKnownFPClass(ConstantFP::get(FPTy, 1.0), DL) 1655 .cannotBeOrderedLessThanZero()); 1656 EXPECT_FALSE(computeKnownFPClass(ConstantFP::get(FPTy, -1.0), DL) 1657 .cannotBeOrderedLessThanZero()); 1658 1659 EXPECT_TRUE( 1660 computeKnownFPClass( 1661 ConstantFP::get(FPTy, APFloat::getSmallest(FPTy->getFltSemantics(), 1662 /*Negative=*/false)), 1663 DL) 1664 .cannotBeOrderedLessThanZero()); 1665 EXPECT_FALSE( 1666 computeKnownFPClass( 1667 ConstantFP::get(FPTy, APFloat::getSmallest(FPTy->getFltSemantics(), 1668 /*Negative=*/true)), 1669 DL) 1670 .cannotBeOrderedLessThanZero()); 1671 1672 EXPECT_TRUE( 1673 computeKnownFPClass(ConstantFP::getQNaN(FPTy, /*Negative=*/false), DL) 1674 .cannotBeOrderedLessThanZero()); 1675 EXPECT_TRUE( 1676 computeKnownFPClass(ConstantFP::getQNaN(FPTy, /*Negative=*/true), DL) 1677 .cannotBeOrderedLessThanZero()); 1678 EXPECT_TRUE( 1679 computeKnownFPClass(ConstantFP::getSNaN(FPTy, /*Negative=*/false), DL) 1680 .cannotBeOrderedLessThanZero()); 1681 EXPECT_TRUE( 1682 computeKnownFPClass(ConstantFP::getSNaN(FPTy, /*Negative=*/true), DL) 1683 .cannotBeOrderedLessThanZero()); 1684 } 1685 1686 TEST_F(ValueTrackingTest, isNonZeroRecurrence) { 1687 parseAssembly(R"( 1688 define i1 @test(i8 %n, i8 %r) { 1689 entry: 1690 br label %loop 1691 loop: 1692 %p = phi i8 [ -1, %entry ], [ %next, %loop ] 1693 %next = add nsw i8 %p, -1 1694 %cmp1 = icmp eq i8 %p, %n 1695 br i1 %cmp1, label %exit, label %loop 1696 exit: 1697 %A = or i8 %p, %r 1698 %CxtI = icmp eq i8 %A, 0 1699 ret i1 %CxtI 1700 } 1701 )"); 1702 const DataLayout &DL = M->getDataLayout(); 1703 AssumptionCache AC(*F); 1704 EXPECT_TRUE(isKnownNonZero(A, DL, 0, &AC, CxtI)); 1705 } 1706 1707 TEST_F(ValueTrackingTest, KnownNonZeroFromDomCond) { 1708 parseAssembly(R"( 1709 declare ptr @f_i8() 1710 define void @test(i1 %c) { 1711 %A = call ptr @f_i8() 1712 %B = call ptr @f_i8() 1713 %c1 = icmp ne ptr %A, null 1714 %cond = and i1 %c1, %c 1715 br i1 %cond, label %T, label %Q 1716 T: 1717 %CxtI = add i32 0, 0 1718 ret void 1719 Q: 1720 %CxtI2 = add i32 0, 0 1721 ret void 1722 } 1723 )"); 1724 AssumptionCache AC(*F); 1725 DominatorTree DT(*F); 1726 const DataLayout &DL = M->getDataLayout(); 1727 EXPECT_EQ(isKnownNonZero(A, DL, 0, &AC, CxtI, &DT), true); 1728 EXPECT_EQ(isKnownNonZero(A, DL, 0, &AC, CxtI2, &DT), false); 1729 } 1730 1731 TEST_F(ValueTrackingTest, KnownNonZeroFromDomCond2) { 1732 parseAssembly(R"( 1733 declare ptr @f_i8() 1734 define void @test(i1 %c) { 1735 %A = call ptr @f_i8() 1736 %B = call ptr @f_i8() 1737 %c1 = icmp ne ptr %A, null 1738 %cond = select i1 %c, i1 %c1, i1 false 1739 br i1 %cond, label %T, label %Q 1740 T: 1741 %CxtI = add i32 0, 0 1742 ret void 1743 Q: 1744 %CxtI2 = add i32 0, 0 1745 ret void 1746 } 1747 )"); 1748 AssumptionCache AC(*F); 1749 DominatorTree DT(*F); 1750 const DataLayout &DL = M->getDataLayout(); 1751 EXPECT_EQ(isKnownNonZero(A, DL, 0, &AC, CxtI, &DT), true); 1752 EXPECT_EQ(isKnownNonZero(A, DL, 0, &AC, CxtI2, &DT), false); 1753 } 1754 1755 TEST_F(ValueTrackingTest, IsImpliedConditionAnd) { 1756 parseAssembly(R"( 1757 define void @test(i32 %x, i32 %y) { 1758 %c1 = icmp ult i32 %x, 10 1759 %c2 = icmp ult i32 %y, 15 1760 %A = and i1 %c1, %c2 1761 ; x < 10 /\ y < 15 1762 %A2 = icmp ult i32 %x, 20 1763 %A3 = icmp uge i32 %y, 20 1764 %A4 = icmp ult i32 %x, 5 1765 ret void 1766 } 1767 )"); 1768 const DataLayout &DL = M->getDataLayout(); 1769 EXPECT_EQ(isImpliedCondition(A, A2, DL), true); 1770 EXPECT_EQ(isImpliedCondition(A, A3, DL), false); 1771 EXPECT_EQ(isImpliedCondition(A, A4, DL), std::nullopt); 1772 } 1773 1774 TEST_F(ValueTrackingTest, IsImpliedConditionAnd2) { 1775 parseAssembly(R"( 1776 define void @test(i32 %x, i32 %y) { 1777 %c1 = icmp ult i32 %x, 10 1778 %c2 = icmp ult i32 %y, 15 1779 %A = select i1 %c1, i1 %c2, i1 false 1780 ; x < 10 /\ y < 15 1781 %A2 = icmp ult i32 %x, 20 1782 %A3 = icmp uge i32 %y, 20 1783 %A4 = icmp ult i32 %x, 5 1784 ret void 1785 } 1786 )"); 1787 const DataLayout &DL = M->getDataLayout(); 1788 EXPECT_EQ(isImpliedCondition(A, A2, DL), true); 1789 EXPECT_EQ(isImpliedCondition(A, A3, DL), false); 1790 EXPECT_EQ(isImpliedCondition(A, A4, DL), std::nullopt); 1791 } 1792 1793 TEST_F(ValueTrackingTest, IsImpliedConditionAndVec) { 1794 parseAssembly(R"( 1795 define void @test(<2 x i8> %x, <2 x i8> %y) { 1796 %A = icmp ult <2 x i8> %x, %y 1797 %A2 = icmp ule <2 x i8> %x, %y 1798 ret void 1799 } 1800 )"); 1801 const DataLayout &DL = M->getDataLayout(); 1802 EXPECT_EQ(isImpliedCondition(A, A2, DL), true); 1803 } 1804 1805 TEST_F(ValueTrackingTest, IsImpliedConditionOr) { 1806 parseAssembly(R"( 1807 define void @test(i32 %x, i32 %y) { 1808 %c1 = icmp ult i32 %x, 10 1809 %c2 = icmp ult i32 %y, 15 1810 %A = or i1 %c1, %c2 ; negated 1811 ; x >= 10 /\ y >= 15 1812 %A2 = icmp ult i32 %x, 5 1813 %A3 = icmp uge i32 %y, 10 1814 %A4 = icmp ult i32 %x, 15 1815 ret void 1816 } 1817 )"); 1818 const DataLayout &DL = M->getDataLayout(); 1819 EXPECT_EQ(isImpliedCondition(A, A2, DL, false), false); 1820 EXPECT_EQ(isImpliedCondition(A, A3, DL, false), true); 1821 EXPECT_EQ(isImpliedCondition(A, A4, DL, false), std::nullopt); 1822 } 1823 1824 TEST_F(ValueTrackingTest, IsImpliedConditionOr2) { 1825 parseAssembly(R"( 1826 define void @test(i32 %x, i32 %y) { 1827 %c1 = icmp ult i32 %x, 10 1828 %c2 = icmp ult i32 %y, 15 1829 %A = select i1 %c1, i1 true, i1 %c2 ; negated 1830 ; x >= 10 /\ y >= 15 1831 %A2 = icmp ult i32 %x, 5 1832 %A3 = icmp uge i32 %y, 10 1833 %A4 = icmp ult i32 %x, 15 1834 ret void 1835 } 1836 )"); 1837 const DataLayout &DL = M->getDataLayout(); 1838 EXPECT_EQ(isImpliedCondition(A, A2, DL, false), false); 1839 EXPECT_EQ(isImpliedCondition(A, A3, DL, false), true); 1840 EXPECT_EQ(isImpliedCondition(A, A4, DL, false), std::nullopt); 1841 } 1842 1843 TEST_F(ComputeKnownBitsTest, KnownNonZeroShift) { 1844 // %q is known nonzero without known bits. 1845 // Because %q is nonzero, %A[0] is known to be zero. 1846 parseAssembly( 1847 "define i8 @test(i8 %p, ptr %pq) {\n" 1848 " %q = load i8, ptr %pq, !range !0\n" 1849 " %A = shl i8 %p, %q\n" 1850 " ret i8 %A\n" 1851 "}\n" 1852 "!0 = !{ i8 1, i8 5 }\n"); 1853 expectKnownBits(/*zero*/ 1u, /*one*/ 0u); 1854 } 1855 1856 TEST_F(ComputeKnownBitsTest, ComputeKnownFshl) { 1857 // fshl(....1111....0000, 00..1111........, 6) 1858 // = 11....000000..11 1859 parseAssembly( 1860 "define i16 @test(i16 %a, i16 %b) {\n" 1861 " %aa = shl i16 %a, 4\n" 1862 " %bb = lshr i16 %b, 2\n" 1863 " %aaa = or i16 %aa, 3840\n" 1864 " %bbb = or i16 %bb, 3840\n" 1865 " %A = call i16 @llvm.fshl.i16(i16 %aaa, i16 %bbb, i16 6)\n" 1866 " ret i16 %A\n" 1867 "}\n" 1868 "declare i16 @llvm.fshl.i16(i16, i16, i16)\n"); 1869 expectKnownBits(/*zero*/ 1008u, /*one*/ 49155u); 1870 } 1871 1872 TEST_F(ComputeKnownBitsTest, ComputeKnownFshr) { 1873 // fshr(....1111....0000, 00..1111........, 26) 1874 // = 11....000000..11 1875 parseAssembly( 1876 "define i16 @test(i16 %a, i16 %b) {\n" 1877 " %aa = shl i16 %a, 4\n" 1878 " %bb = lshr i16 %b, 2\n" 1879 " %aaa = or i16 %aa, 3840\n" 1880 " %bbb = or i16 %bb, 3840\n" 1881 " %A = call i16 @llvm.fshr.i16(i16 %aaa, i16 %bbb, i16 26)\n" 1882 " ret i16 %A\n" 1883 "}\n" 1884 "declare i16 @llvm.fshr.i16(i16, i16, i16)\n"); 1885 expectKnownBits(/*zero*/ 1008u, /*one*/ 49155u); 1886 } 1887 1888 TEST_F(ComputeKnownBitsTest, ComputeKnownFshlZero) { 1889 // fshl(....1111....0000, 00..1111........, 0) 1890 // = ....1111....0000 1891 parseAssembly( 1892 "define i16 @test(i16 %a, i16 %b) {\n" 1893 " %aa = shl i16 %a, 4\n" 1894 " %bb = lshr i16 %b, 2\n" 1895 " %aaa = or i16 %aa, 3840\n" 1896 " %bbb = or i16 %bb, 3840\n" 1897 " %A = call i16 @llvm.fshl.i16(i16 %aaa, i16 %bbb, i16 0)\n" 1898 " ret i16 %A\n" 1899 "}\n" 1900 "declare i16 @llvm.fshl.i16(i16, i16, i16)\n"); 1901 expectKnownBits(/*zero*/ 15u, /*one*/ 3840u); 1902 } 1903 1904 TEST_F(ComputeKnownBitsTest, ComputeKnownUAddSatLeadingOnes) { 1905 // uadd.sat(1111...1, ........) 1906 // = 1111.... 1907 parseAssembly( 1908 "define i8 @test(i8 %a, i8 %b) {\n" 1909 " %aa = or i8 %a, 241\n" 1910 " %A = call i8 @llvm.uadd.sat.i8(i8 %aa, i8 %b)\n" 1911 " ret i8 %A\n" 1912 "}\n" 1913 "declare i8 @llvm.uadd.sat.i8(i8, i8)\n"); 1914 expectKnownBits(/*zero*/ 0u, /*one*/ 240u); 1915 } 1916 1917 TEST_F(ComputeKnownBitsTest, ComputeKnownUAddSatOnesPreserved) { 1918 // uadd.sat(00...011, .1...110) 1919 // = .......1 1920 parseAssembly( 1921 "define i8 @test(i8 %a, i8 %b) {\n" 1922 " %aa = or i8 %a, 3\n" 1923 " %aaa = and i8 %aa, 59\n" 1924 " %bb = or i8 %b, 70\n" 1925 " %bbb = and i8 %bb, 254\n" 1926 " %A = call i8 @llvm.uadd.sat.i8(i8 %aaa, i8 %bbb)\n" 1927 " ret i8 %A\n" 1928 "}\n" 1929 "declare i8 @llvm.uadd.sat.i8(i8, i8)\n"); 1930 expectKnownBits(/*zero*/ 0u, /*one*/ 1u); 1931 } 1932 1933 TEST_F(ComputeKnownBitsTest, ComputeKnownUSubSatLHSLeadingZeros) { 1934 // usub.sat(0000...0, ........) 1935 // = 0000.... 1936 parseAssembly( 1937 "define i8 @test(i8 %a, i8 %b) {\n" 1938 " %aa = and i8 %a, 14\n" 1939 " %A = call i8 @llvm.usub.sat.i8(i8 %aa, i8 %b)\n" 1940 " ret i8 %A\n" 1941 "}\n" 1942 "declare i8 @llvm.usub.sat.i8(i8, i8)\n"); 1943 expectKnownBits(/*zero*/ 240u, /*one*/ 0u); 1944 } 1945 1946 TEST_F(ComputeKnownBitsTest, ComputeKnownUSubSatRHSLeadingOnes) { 1947 // usub.sat(........, 1111...1) 1948 // = 0000.... 1949 parseAssembly( 1950 "define i8 @test(i8 %a, i8 %b) {\n" 1951 " %bb = or i8 %a, 241\n" 1952 " %A = call i8 @llvm.usub.sat.i8(i8 %a, i8 %bb)\n" 1953 " ret i8 %A\n" 1954 "}\n" 1955 "declare i8 @llvm.usub.sat.i8(i8, i8)\n"); 1956 expectKnownBits(/*zero*/ 240u, /*one*/ 0u); 1957 } 1958 1959 TEST_F(ComputeKnownBitsTest, ComputeKnownUSubSatZerosPreserved) { 1960 // usub.sat(11...011, .1...110) 1961 // = ......0. 1962 parseAssembly( 1963 "define i8 @test(i8 %a, i8 %b) {\n" 1964 " %aa = or i8 %a, 195\n" 1965 " %aaa = and i8 %aa, 251\n" 1966 " %bb = or i8 %b, 70\n" 1967 " %bbb = and i8 %bb, 254\n" 1968 " %A = call i8 @llvm.usub.sat.i8(i8 %aaa, i8 %bbb)\n" 1969 " ret i8 %A\n" 1970 "}\n" 1971 "declare i8 @llvm.usub.sat.i8(i8, i8)\n"); 1972 expectKnownBits(/*zero*/ 2u, /*one*/ 0u); 1973 } 1974 1975 TEST_F(ComputeKnownBitsTest, ComputeKnownBitsPtrToIntTrunc) { 1976 // ptrtoint truncates the pointer type. 1977 parseAssembly( 1978 "define void @test(ptr %p) {\n" 1979 " %A = load ptr, ptr %p\n" 1980 " %i = ptrtoint ptr %A to i32\n" 1981 " %m = and i32 %i, 31\n" 1982 " %c = icmp eq i32 %m, 0\n" 1983 " call void @llvm.assume(i1 %c)\n" 1984 " ret void\n" 1985 "}\n" 1986 "declare void @llvm.assume(i1)\n"); 1987 AssumptionCache AC(*F); 1988 KnownBits Known = computeKnownBits( 1989 A, M->getDataLayout(), /* Depth */ 0, &AC, F->front().getTerminator()); 1990 EXPECT_EQ(Known.Zero.getZExtValue(), 31u); 1991 EXPECT_EQ(Known.One.getZExtValue(), 0u); 1992 } 1993 1994 TEST_F(ComputeKnownBitsTest, ComputeKnownBitsPtrToIntZext) { 1995 // ptrtoint zero extends the pointer type. 1996 parseAssembly( 1997 "define void @test(ptr %p) {\n" 1998 " %A = load ptr, ptr %p\n" 1999 " %i = ptrtoint ptr %A to i128\n" 2000 " %m = and i128 %i, 31\n" 2001 " %c = icmp eq i128 %m, 0\n" 2002 " call void @llvm.assume(i1 %c)\n" 2003 " ret void\n" 2004 "}\n" 2005 "declare void @llvm.assume(i1)\n"); 2006 AssumptionCache AC(*F); 2007 KnownBits Known = computeKnownBits( 2008 A, M->getDataLayout(), /* Depth */ 0, &AC, F->front().getTerminator()); 2009 EXPECT_EQ(Known.Zero.getZExtValue(), 31u); 2010 EXPECT_EQ(Known.One.getZExtValue(), 0u); 2011 } 2012 2013 TEST_F(ComputeKnownBitsTest, ComputeKnownBitsFreeze) { 2014 parseAssembly("define void @test() {\n" 2015 " %m = call i32 @any_num()\n" 2016 " %A = freeze i32 %m\n" 2017 " %n = and i32 %m, 31\n" 2018 " %c = icmp eq i32 %n, 0\n" 2019 " call void @llvm.assume(i1 %c)\n" 2020 " ret void\n" 2021 "}\n" 2022 "declare void @llvm.assume(i1)\n" 2023 "declare i32 @any_num()\n"); 2024 AssumptionCache AC(*F); 2025 KnownBits Known = computeKnownBits(A, M->getDataLayout(), /* Depth */ 0, &AC, 2026 F->front().getTerminator()); 2027 EXPECT_EQ(Known.Zero.getZExtValue(), 31u); 2028 EXPECT_EQ(Known.One.getZExtValue(), 0u); 2029 } 2030 2031 TEST_F(ComputeKnownBitsTest, ComputeKnownBitsAddWithRange) { 2032 parseAssembly("define void @test(ptr %p) {\n" 2033 " %A = load i64, ptr %p, !range !{i64 64, i64 65536}\n" 2034 " %APlus512 = add i64 %A, 512\n" 2035 " %c = icmp ugt i64 %APlus512, 523\n" 2036 " call void @llvm.assume(i1 %c)\n" 2037 " ret void\n" 2038 "}\n" 2039 "declare void @llvm.assume(i1)\n"); 2040 AssumptionCache AC(*F); 2041 KnownBits Known = computeKnownBits(A, M->getDataLayout(), /* Depth */ 0, &AC, 2042 F->front().getTerminator()); 2043 EXPECT_EQ(Known.Zero.getZExtValue(), ~(65536llu - 1)); 2044 EXPECT_EQ(Known.One.getZExtValue(), 0u); 2045 Instruction &APlus512 = findInstructionByName(F, "APlus512"); 2046 Known = computeKnownBits(&APlus512, M->getDataLayout(), /* Depth */ 0, &AC, 2047 F->front().getTerminator()); 2048 // We know of one less zero because 512 may have produced a 1 that 2049 // got carried all the way to the first trailing zero. 2050 EXPECT_EQ(Known.Zero.getZExtValue(), (~(65536llu - 1)) << 1); 2051 EXPECT_EQ(Known.One.getZExtValue(), 0u); 2052 // The known range is not precise given computeKnownBits works 2053 // with the masks of zeros and ones, not the ranges. 2054 EXPECT_EQ(Known.getMinValue(), 0u); 2055 EXPECT_EQ(Known.getMaxValue(), 131071); 2056 } 2057 2058 TEST_F(ComputeKnownBitsTest, ComputeKnownBitsUnknownVScale) { 2059 Module M("", Context); 2060 IRBuilder<> Builder(Context); 2061 Function *TheFn = 2062 Intrinsic::getDeclaration(&M, Intrinsic::vscale, {Builder.getInt32Ty()}); 2063 CallInst *CI = Builder.CreateCall(TheFn, {}, {}, ""); 2064 2065 KnownBits Known = computeKnownBits(CI, M.getDataLayout(), /* Depth */ 0); 2066 // There is no parent function so we cannot look up the vscale_range 2067 // attribute to determine the number of bits. 2068 EXPECT_EQ(Known.One.getZExtValue(), 0u); 2069 EXPECT_EQ(Known.Zero.getZExtValue(), 0u); 2070 2071 BasicBlock *BB = BasicBlock::Create(Context); 2072 CI->insertInto(BB, BB->end()); 2073 Known = computeKnownBits(CI, M.getDataLayout(), /* Depth */ 0); 2074 // There is no parent function so we cannot look up the vscale_range 2075 // attribute to determine the number of bits. 2076 EXPECT_EQ(Known.One.getZExtValue(), 0u); 2077 EXPECT_EQ(Known.Zero.getZExtValue(), 0u); 2078 2079 CI->removeFromParent(); 2080 delete CI; 2081 delete BB; 2082 } 2083 2084 // 512 + [32, 64) doesn't produce overlapping bits. 2085 // Make sure we get all the individual bits properly. 2086 TEST_F(ComputeKnownBitsTest, ComputeKnownBitsAddWithRangeNoOverlap) { 2087 parseAssembly("define void @test(ptr %p) {\n" 2088 " %A = load i64, ptr %p, !range !{i64 32, i64 64}\n" 2089 " %APlus512 = add i64 %A, 512\n" 2090 " %c = icmp ugt i64 %APlus512, 523\n" 2091 " call void @llvm.assume(i1 %c)\n" 2092 " ret void\n" 2093 "}\n" 2094 "declare void @llvm.assume(i1)\n"); 2095 AssumptionCache AC(*F); 2096 KnownBits Known = computeKnownBits(A, M->getDataLayout(), /* Depth */ 0, &AC, 2097 F->front().getTerminator()); 2098 EXPECT_EQ(Known.Zero.getZExtValue(), ~(64llu - 1)); 2099 EXPECT_EQ(Known.One.getZExtValue(), 32u); 2100 Instruction &APlus512 = findInstructionByName(F, "APlus512"); 2101 Known = computeKnownBits(&APlus512, M->getDataLayout(), /* Depth */ 0, &AC, 2102 F->front().getTerminator()); 2103 EXPECT_EQ(Known.Zero.getZExtValue(), ~512llu & ~(64llu - 1)); 2104 EXPECT_EQ(Known.One.getZExtValue(), 512u | 32u); 2105 // The known range is not precise given computeKnownBits works 2106 // with the masks of zeros and ones, not the ranges. 2107 EXPECT_EQ(Known.getMinValue(), 544); 2108 EXPECT_EQ(Known.getMaxValue(), 575); 2109 } 2110 2111 TEST_F(ComputeKnownBitsTest, ComputeKnownBitsGEPWithRange) { 2112 parseAssembly( 2113 "define void @test(ptr %p) {\n" 2114 " %A = load i64, ptr %p, !range !{i64 64, i64 65536}\n" 2115 " %APtr = inttoptr i64 %A to float*" 2116 " %APtrPlus512 = getelementptr float, float* %APtr, i32 128\n" 2117 " %c = icmp ugt float* %APtrPlus512, inttoptr (i32 523 to float*)\n" 2118 " call void @llvm.assume(i1 %c)\n" 2119 " ret void\n" 2120 "}\n" 2121 "declare void @llvm.assume(i1)\n"); 2122 AssumptionCache AC(*F); 2123 KnownBits Known = computeKnownBits(A, M->getDataLayout(), /* Depth */ 0, &AC, 2124 F->front().getTerminator()); 2125 EXPECT_EQ(Known.Zero.getZExtValue(), ~(65536llu - 1)); 2126 EXPECT_EQ(Known.One.getZExtValue(), 0u); 2127 Instruction &APtrPlus512 = findInstructionByName(F, "APtrPlus512"); 2128 Known = computeKnownBits(&APtrPlus512, M->getDataLayout(), /* Depth */ 0, &AC, 2129 F->front().getTerminator()); 2130 // We know of one less zero because 512 may have produced a 1 that 2131 // got carried all the way to the first trailing zero. 2132 EXPECT_EQ(Known.Zero.getZExtValue(), ~(65536llu - 1) << 1); 2133 EXPECT_EQ(Known.One.getZExtValue(), 0u); 2134 // The known range is not precise given computeKnownBits works 2135 // with the masks of zeros and ones, not the ranges. 2136 EXPECT_EQ(Known.getMinValue(), 0u); 2137 EXPECT_EQ(Known.getMaxValue(), 131071); 2138 } 2139 2140 // 4*128 + [32, 64) doesn't produce overlapping bits. 2141 // Make sure we get all the individual bits properly. 2142 // This test is useful to check that we account for the scaling factor 2143 // in the gep. Indeed, gep float, [32,64), 128 is not 128 + [32,64). 2144 TEST_F(ComputeKnownBitsTest, ComputeKnownBitsGEPWithRangeNoOverlap) { 2145 parseAssembly( 2146 "define void @test(ptr %p) {\n" 2147 " %A = load i64, ptr %p, !range !{i64 32, i64 64}\n" 2148 " %APtr = inttoptr i64 %A to float*" 2149 " %APtrPlus512 = getelementptr float, float* %APtr, i32 128\n" 2150 " %c = icmp ugt float* %APtrPlus512, inttoptr (i32 523 to float*)\n" 2151 " call void @llvm.assume(i1 %c)\n" 2152 " ret void\n" 2153 "}\n" 2154 "declare void @llvm.assume(i1)\n"); 2155 AssumptionCache AC(*F); 2156 KnownBits Known = computeKnownBits(A, M->getDataLayout(), /* Depth */ 0, &AC, 2157 F->front().getTerminator()); 2158 EXPECT_EQ(Known.Zero.getZExtValue(), ~(64llu - 1)); 2159 EXPECT_EQ(Known.One.getZExtValue(), 32u); 2160 Instruction &APtrPlus512 = findInstructionByName(F, "APtrPlus512"); 2161 Known = computeKnownBits(&APtrPlus512, M->getDataLayout(), /* Depth */ 0, &AC, 2162 F->front().getTerminator()); 2163 EXPECT_EQ(Known.Zero.getZExtValue(), ~512llu & ~(64llu - 1)); 2164 EXPECT_EQ(Known.One.getZExtValue(), 512u | 32u); 2165 // The known range is not precise given computeKnownBits works 2166 // with the masks of zeros and ones, not the ranges. 2167 EXPECT_EQ(Known.getMinValue(), 544); 2168 EXPECT_EQ(Known.getMaxValue(), 575); 2169 } 2170 2171 TEST_F(ValueTrackingTest, HaveNoCommonBitsSet) { 2172 { 2173 // Check for an inverted mask: (X & ~M) op (Y & M). 2174 auto M = parseModule(R"( 2175 define i32 @test(i32 %X, i32 %Y, i32 %M) { 2176 %1 = xor i32 %M, -1 2177 %LHS = and i32 %1, %X 2178 %RHS = and i32 %Y, %M 2179 %Ret = add i32 %LHS, %RHS 2180 ret i32 %Ret 2181 })"); 2182 2183 auto *F = M->getFunction("test"); 2184 auto *LHS = findInstructionByNameOrNull(F, "LHS"); 2185 auto *RHS = findInstructionByNameOrNull(F, "RHS"); 2186 2187 const DataLayout &DL = M->getDataLayout(); 2188 EXPECT_TRUE(haveNoCommonBitsSet(LHS, RHS, DL)); 2189 EXPECT_TRUE(haveNoCommonBitsSet(RHS, LHS, DL)); 2190 } 2191 { 2192 // Check for (A & B) and ~(A | B) 2193 auto M = parseModule(R"( 2194 define void @test(i32 %A, i32 %B) { 2195 %LHS = and i32 %A, %B 2196 %or = or i32 %A, %B 2197 %RHS = xor i32 %or, -1 2198 2199 %LHS2 = and i32 %B, %A 2200 %or2 = or i32 %A, %B 2201 %RHS2 = xor i32 %or2, -1 2202 2203 ret void 2204 })"); 2205 2206 auto *F = M->getFunction("test"); 2207 const DataLayout &DL = M->getDataLayout(); 2208 2209 auto *LHS = findInstructionByNameOrNull(F, "LHS"); 2210 auto *RHS = findInstructionByNameOrNull(F, "RHS"); 2211 EXPECT_TRUE(haveNoCommonBitsSet(LHS, RHS, DL)); 2212 EXPECT_TRUE(haveNoCommonBitsSet(RHS, LHS, DL)); 2213 2214 auto *LHS2 = findInstructionByNameOrNull(F, "LHS2"); 2215 auto *RHS2 = findInstructionByNameOrNull(F, "RHS2"); 2216 EXPECT_TRUE(haveNoCommonBitsSet(LHS2, RHS2, DL)); 2217 EXPECT_TRUE(haveNoCommonBitsSet(RHS2, LHS2, DL)); 2218 } 2219 { 2220 // Check for (A & B) and ~(A | B) in vector version 2221 auto M = parseModule(R"( 2222 define void @test(<2 x i32> %A, <2 x i32> %B) { 2223 %LHS = and <2 x i32> %A, %B 2224 %or = or <2 x i32> %A, %B 2225 %RHS = xor <2 x i32> %or, <i32 -1, i32 -1> 2226 2227 %LHS2 = and <2 x i32> %B, %A 2228 %or2 = or <2 x i32> %A, %B 2229 %RHS2 = xor <2 x i32> %or2, <i32 -1, i32 -1> 2230 2231 ret void 2232 })"); 2233 2234 auto *F = M->getFunction("test"); 2235 const DataLayout &DL = M->getDataLayout(); 2236 2237 auto *LHS = findInstructionByNameOrNull(F, "LHS"); 2238 auto *RHS = findInstructionByNameOrNull(F, "RHS"); 2239 EXPECT_TRUE(haveNoCommonBitsSet(LHS, RHS, DL)); 2240 EXPECT_TRUE(haveNoCommonBitsSet(RHS, LHS, DL)); 2241 2242 auto *LHS2 = findInstructionByNameOrNull(F, "LHS2"); 2243 auto *RHS2 = findInstructionByNameOrNull(F, "RHS2"); 2244 EXPECT_TRUE(haveNoCommonBitsSet(LHS2, RHS2, DL)); 2245 EXPECT_TRUE(haveNoCommonBitsSet(RHS2, LHS2, DL)); 2246 } 2247 } 2248 2249 class IsBytewiseValueTest : public ValueTrackingTest, 2250 public ::testing::WithParamInterface< 2251 std::pair<const char *, const char *>> { 2252 protected: 2253 }; 2254 2255 const std::pair<const char *, const char *> IsBytewiseValueTests[] = { 2256 { 2257 "i8 0", 2258 "i48* null", 2259 }, 2260 { 2261 "i8 undef", 2262 "i48* undef", 2263 }, 2264 { 2265 "i8 0", 2266 "i8 zeroinitializer", 2267 }, 2268 { 2269 "i8 0", 2270 "i8 0", 2271 }, 2272 { 2273 "i8 -86", 2274 "i8 -86", 2275 }, 2276 { 2277 "i8 -1", 2278 "i8 -1", 2279 }, 2280 { 2281 "i8 undef", 2282 "i16 undef", 2283 }, 2284 { 2285 "i8 0", 2286 "i16 0", 2287 }, 2288 { 2289 "", 2290 "i16 7", 2291 }, 2292 { 2293 "i8 -86", 2294 "i16 -21846", 2295 }, 2296 { 2297 "i8 -1", 2298 "i16 -1", 2299 }, 2300 { 2301 "i8 0", 2302 "i48 0", 2303 }, 2304 { 2305 "i8 -1", 2306 "i48 -1", 2307 }, 2308 { 2309 "i8 0", 2310 "i49 0", 2311 }, 2312 { 2313 "", 2314 "i49 -1", 2315 }, 2316 { 2317 "i8 0", 2318 "half 0xH0000", 2319 }, 2320 { 2321 "i8 -85", 2322 "half 0xHABAB", 2323 }, 2324 { 2325 "i8 0", 2326 "float 0.0", 2327 }, 2328 { 2329 "i8 -1", 2330 "float 0xFFFFFFFFE0000000", 2331 }, 2332 { 2333 "i8 0", 2334 "double 0.0", 2335 }, 2336 { 2337 "i8 -15", 2338 "double 0xF1F1F1F1F1F1F1F1", 2339 }, 2340 { 2341 "i8 undef", 2342 "i16* undef", 2343 }, 2344 { 2345 "i8 0", 2346 "i16* inttoptr (i64 0 to i16*)", 2347 }, 2348 { 2349 "i8 -1", 2350 "i16* inttoptr (i64 -1 to i16*)", 2351 }, 2352 { 2353 "i8 -86", 2354 "i16* inttoptr (i64 -6148914691236517206 to i16*)", 2355 }, 2356 { 2357 "", 2358 "i16* inttoptr (i48 -1 to i16*)", 2359 }, 2360 { 2361 "i8 -1", 2362 "i16* inttoptr (i96 -1 to i16*)", 2363 }, 2364 { 2365 "i8 undef", 2366 "[0 x i8] zeroinitializer", 2367 }, 2368 { 2369 "i8 undef", 2370 "[0 x i8] undef", 2371 }, 2372 { 2373 "i8 undef", 2374 "[5 x [0 x i8]] zeroinitializer", 2375 }, 2376 { 2377 "i8 undef", 2378 "[5 x [0 x i8]] undef", 2379 }, 2380 { 2381 "i8 0", 2382 "[6 x i8] zeroinitializer", 2383 }, 2384 { 2385 "i8 undef", 2386 "[6 x i8] undef", 2387 }, 2388 { 2389 "i8 1", 2390 "[5 x i8] [i8 1, i8 1, i8 1, i8 1, i8 1]", 2391 }, 2392 { 2393 "", 2394 "[5 x i64] [i64 1, i64 1, i64 1, i64 1, i64 1]", 2395 }, 2396 { 2397 "i8 -1", 2398 "[5 x i64] [i64 -1, i64 -1, i64 -1, i64 -1, i64 -1]", 2399 }, 2400 { 2401 "", 2402 "[4 x i8] [i8 1, i8 2, i8 1, i8 1]", 2403 }, 2404 { 2405 "i8 1", 2406 "[4 x i8] [i8 1, i8 undef, i8 1, i8 1]", 2407 }, 2408 { 2409 "i8 0", 2410 "<6 x i8> zeroinitializer", 2411 }, 2412 { 2413 "i8 undef", 2414 "<6 x i8> undef", 2415 }, 2416 { 2417 "i8 1", 2418 "<5 x i8> <i8 1, i8 1, i8 1, i8 1, i8 1>", 2419 }, 2420 { 2421 "", 2422 "<5 x i64> <i64 1, i64 1, i64 1, i64 1, i64 1>", 2423 }, 2424 { 2425 "i8 -1", 2426 "<5 x i64> <i64 -1, i64 -1, i64 -1, i64 -1, i64 -1>", 2427 }, 2428 { 2429 "", 2430 "<4 x i8> <i8 1, i8 1, i8 2, i8 1>", 2431 }, 2432 { 2433 "i8 5", 2434 "<2 x i8> < i8 5, i8 undef >", 2435 }, 2436 { 2437 "i8 0", 2438 "[2 x [2 x i16]] zeroinitializer", 2439 }, 2440 { 2441 "i8 undef", 2442 "[2 x [2 x i16]] undef", 2443 }, 2444 { 2445 "i8 -86", 2446 "[2 x [2 x i16]] [[2 x i16] [i16 -21846, i16 -21846], " 2447 "[2 x i16] [i16 -21846, i16 -21846]]", 2448 }, 2449 { 2450 "", 2451 "[2 x [2 x i16]] [[2 x i16] [i16 -21846, i16 -21846], " 2452 "[2 x i16] [i16 -21836, i16 -21846]]", 2453 }, 2454 { 2455 "i8 undef", 2456 "{ } zeroinitializer", 2457 }, 2458 { 2459 "i8 undef", 2460 "{ } undef", 2461 }, 2462 { 2463 "i8 undef", 2464 "{ {}, {} } zeroinitializer", 2465 }, 2466 { 2467 "i8 undef", 2468 "{ {}, {} } undef", 2469 }, 2470 { 2471 "i8 0", 2472 "{i8, i64, i16*} zeroinitializer", 2473 }, 2474 { 2475 "i8 undef", 2476 "{i8, i64, i16*} undef", 2477 }, 2478 { 2479 "i8 -86", 2480 "{i8, i64, i16*} {i8 -86, i64 -6148914691236517206, i16* undef}", 2481 }, 2482 { 2483 "", 2484 "{i8, i64, i16*} {i8 86, i64 -6148914691236517206, i16* undef}", 2485 }, 2486 }; 2487 2488 INSTANTIATE_TEST_SUITE_P(IsBytewiseValueParamTests, IsBytewiseValueTest, 2489 ::testing::ValuesIn(IsBytewiseValueTests)); 2490 2491 TEST_P(IsBytewiseValueTest, IsBytewiseValue) { 2492 auto M = parseModule(std::string("@test = global ") + GetParam().second); 2493 GlobalVariable *GV = dyn_cast<GlobalVariable>(M->getNamedValue("test")); 2494 Value *Actual = isBytewiseValue(GV->getInitializer(), M->getDataLayout()); 2495 std::string Buff; 2496 raw_string_ostream S(Buff); 2497 if (Actual) 2498 S << *Actual; 2499 EXPECT_EQ(GetParam().first, S.str()); 2500 } 2501 2502 TEST_F(ValueTrackingTest, ComputeConstantRange) { 2503 { 2504 // Assumptions: 2505 // * stride >= 5 2506 // * stride < 10 2507 // 2508 // stride = [5, 10) 2509 auto M = parseModule(R"( 2510 declare void @llvm.assume(i1) 2511 2512 define i32 @test(i32 %stride) { 2513 %gt = icmp uge i32 %stride, 5 2514 call void @llvm.assume(i1 %gt) 2515 %lt = icmp ult i32 %stride, 10 2516 call void @llvm.assume(i1 %lt) 2517 %stride.plus.one = add nsw nuw i32 %stride, 1 2518 ret i32 %stride.plus.one 2519 })"); 2520 Function *F = M->getFunction("test"); 2521 2522 AssumptionCache AC(*F); 2523 Value *Stride = &*F->arg_begin(); 2524 ConstantRange CR1 = computeConstantRange(Stride, false, true, &AC, nullptr); 2525 EXPECT_TRUE(CR1.isFullSet()); 2526 2527 Instruction *I = &findInstructionByName(F, "stride.plus.one"); 2528 ConstantRange CR2 = computeConstantRange(Stride, false, true, &AC, I); 2529 EXPECT_EQ(5, CR2.getLower()); 2530 EXPECT_EQ(10, CR2.getUpper()); 2531 } 2532 2533 { 2534 // Assumptions: 2535 // * stride >= 5 2536 // * stride < 200 2537 // * stride == 99 2538 // 2539 // stride = [99, 100) 2540 auto M = parseModule(R"( 2541 declare void @llvm.assume(i1) 2542 2543 define i32 @test(i32 %stride) { 2544 %gt = icmp uge i32 %stride, 5 2545 call void @llvm.assume(i1 %gt) 2546 %lt = icmp ult i32 %stride, 200 2547 call void @llvm.assume(i1 %lt) 2548 %eq = icmp eq i32 %stride, 99 2549 call void @llvm.assume(i1 %eq) 2550 %stride.plus.one = add nsw nuw i32 %stride, 1 2551 ret i32 %stride.plus.one 2552 })"); 2553 Function *F = M->getFunction("test"); 2554 2555 AssumptionCache AC(*F); 2556 Value *Stride = &*F->arg_begin(); 2557 Instruction *I = &findInstructionByName(F, "stride.plus.one"); 2558 ConstantRange CR = computeConstantRange(Stride, false, true, &AC, I); 2559 EXPECT_EQ(99, *CR.getSingleElement()); 2560 } 2561 2562 { 2563 // Assumptions: 2564 // * stride >= 5 2565 // * stride >= 50 2566 // * stride < 100 2567 // * stride < 200 2568 // 2569 // stride = [50, 100) 2570 auto M = parseModule(R"( 2571 declare void @llvm.assume(i1) 2572 2573 define i32 @test(i32 %stride, i1 %cond) { 2574 %gt = icmp uge i32 %stride, 5 2575 call void @llvm.assume(i1 %gt) 2576 %gt.2 = icmp uge i32 %stride, 50 2577 call void @llvm.assume(i1 %gt.2) 2578 br i1 %cond, label %bb1, label %bb2 2579 2580 bb1: 2581 %lt = icmp ult i32 %stride, 200 2582 call void @llvm.assume(i1 %lt) 2583 %lt.2 = icmp ult i32 %stride, 100 2584 call void @llvm.assume(i1 %lt.2) 2585 %stride.plus.one = add nsw nuw i32 %stride, 1 2586 ret i32 %stride.plus.one 2587 2588 bb2: 2589 ret i32 0 2590 })"); 2591 Function *F = M->getFunction("test"); 2592 2593 AssumptionCache AC(*F); 2594 Value *Stride = &*F->arg_begin(); 2595 Instruction *GT2 = &findInstructionByName(F, "gt.2"); 2596 ConstantRange CR = computeConstantRange(Stride, false, true, &AC, GT2); 2597 EXPECT_EQ(5, CR.getLower()); 2598 EXPECT_EQ(0, CR.getUpper()); 2599 2600 Instruction *I = &findInstructionByName(F, "stride.plus.one"); 2601 ConstantRange CR2 = computeConstantRange(Stride, false, true, &AC, I); 2602 EXPECT_EQ(50, CR2.getLower()); 2603 EXPECT_EQ(100, CR2.getUpper()); 2604 } 2605 2606 { 2607 // Assumptions: 2608 // * stride > 5 2609 // * stride < 5 2610 // 2611 // stride = empty range, as the assumptions contradict each other. 2612 auto M = parseModule(R"( 2613 declare void @llvm.assume(i1) 2614 2615 define i32 @test(i32 %stride, i1 %cond) { 2616 %gt = icmp ugt i32 %stride, 5 2617 call void @llvm.assume(i1 %gt) 2618 %lt = icmp ult i32 %stride, 5 2619 call void @llvm.assume(i1 %lt) 2620 %stride.plus.one = add nsw nuw i32 %stride, 1 2621 ret i32 %stride.plus.one 2622 })"); 2623 Function *F = M->getFunction("test"); 2624 2625 AssumptionCache AC(*F); 2626 Value *Stride = &*F->arg_begin(); 2627 2628 Instruction *I = &findInstructionByName(F, "stride.plus.one"); 2629 ConstantRange CR = computeConstantRange(Stride, false, true, &AC, I); 2630 EXPECT_TRUE(CR.isEmptySet()); 2631 } 2632 2633 { 2634 // Assumptions: 2635 // * x.1 >= 5 2636 // * x.2 < x.1 2637 // 2638 // stride = [0, -1) 2639 auto M = parseModule(R"( 2640 declare void @llvm.assume(i1) 2641 2642 define i32 @test(i32 %x.1, i32 %x.2) { 2643 %gt = icmp uge i32 %x.1, 5 2644 call void @llvm.assume(i1 %gt) 2645 %lt = icmp ult i32 %x.2, %x.1 2646 call void @llvm.assume(i1 %lt) 2647 %stride.plus.one = add nsw nuw i32 %x.1, 1 2648 ret i32 %stride.plus.one 2649 })"); 2650 Function *F = M->getFunction("test"); 2651 2652 AssumptionCache AC(*F); 2653 Value *X1 = &*(F->arg_begin()); 2654 Value *X2 = &*std::next(F->arg_begin()); 2655 2656 Instruction *I = &findInstructionByName(F, "stride.plus.one"); 2657 ConstantRange CR1 = computeConstantRange(X1, false, true, &AC, I); 2658 ConstantRange CR2 = computeConstantRange(X2, false, true, &AC, I); 2659 2660 EXPECT_EQ(5, CR1.getLower()); 2661 EXPECT_EQ(0, CR1.getUpper()); 2662 2663 EXPECT_EQ(0, CR2.getLower()); 2664 EXPECT_EQ(0xffffffff, CR2.getUpper()); 2665 2666 // Check the depth cutoff results in a conservative result (full set) by 2667 // passing Depth == MaxDepth == 6. 2668 ConstantRange CR3 = computeConstantRange(X2, false, true, &AC, I, nullptr, 6); 2669 EXPECT_TRUE(CR3.isFullSet()); 2670 } 2671 { 2672 // Assumptions: 2673 // * x.2 <= x.1 2674 auto M = parseModule(R"( 2675 declare void @llvm.assume(i1) 2676 2677 define i32 @test(i32 %x.1, i32 %x.2) { 2678 %lt = icmp ule i32 %x.2, %x.1 2679 call void @llvm.assume(i1 %lt) 2680 %stride.plus.one = add nsw nuw i32 %x.1, 1 2681 ret i32 %stride.plus.one 2682 })"); 2683 Function *F = M->getFunction("test"); 2684 2685 AssumptionCache AC(*F); 2686 Value *X2 = &*std::next(F->arg_begin()); 2687 2688 Instruction *I = &findInstructionByName(F, "stride.plus.one"); 2689 ConstantRange CR1 = computeConstantRange(X2, false, true, &AC, I); 2690 // If we don't know the value of x.2, we don't know the value of x.1. 2691 EXPECT_TRUE(CR1.isFullSet()); 2692 } 2693 } 2694 2695 struct FindAllocaForValueTestParams { 2696 const char *IR; 2697 bool AnyOffsetResult; 2698 bool ZeroOffsetResult; 2699 }; 2700 2701 class FindAllocaForValueTest 2702 : public ValueTrackingTest, 2703 public ::testing::WithParamInterface<FindAllocaForValueTestParams> { 2704 protected: 2705 }; 2706 2707 const FindAllocaForValueTestParams FindAllocaForValueTests[] = { 2708 {R"( 2709 define void @test() { 2710 %a = alloca i64 2711 %r = bitcast ptr %a to ptr 2712 ret void 2713 })", 2714 true, true}, 2715 2716 {R"( 2717 define void @test() { 2718 %a = alloca i32 2719 %r = getelementptr i32, ptr %a, i32 1 2720 ret void 2721 })", 2722 true, false}, 2723 2724 {R"( 2725 define void @test() { 2726 %a = alloca i32 2727 %r = getelementptr i32, ptr %a, i32 0 2728 ret void 2729 })", 2730 true, true}, 2731 2732 {R"( 2733 define void @test(i1 %cond) { 2734 entry: 2735 %a = alloca i32 2736 br label %bb1 2737 2738 bb1: 2739 %r = phi ptr [ %a, %entry ], [ %r, %bb1 ] 2740 br i1 %cond, label %bb1, label %exit 2741 2742 exit: 2743 ret void 2744 })", 2745 true, true}, 2746 2747 {R"( 2748 define void @test(i1 %cond) { 2749 %a = alloca i32 2750 %r = select i1 %cond, ptr %a, ptr %a 2751 ret void 2752 })", 2753 true, true}, 2754 2755 {R"( 2756 define void @test(i1 %cond) { 2757 %a = alloca i32 2758 %b = alloca i32 2759 %r = select i1 %cond, ptr %a, ptr %b 2760 ret void 2761 })", 2762 false, false}, 2763 2764 {R"( 2765 define void @test(i1 %cond) { 2766 entry: 2767 %a = alloca i64 2768 %a32 = bitcast ptr %a to ptr 2769 br label %bb1 2770 2771 bb1: 2772 %x = phi ptr [ %a32, %entry ], [ %x, %bb1 ] 2773 %r = getelementptr i32, ptr %x, i32 1 2774 br i1 %cond, label %bb1, label %exit 2775 2776 exit: 2777 ret void 2778 })", 2779 true, false}, 2780 2781 {R"( 2782 define void @test(i1 %cond) { 2783 entry: 2784 %a = alloca i64 2785 %a32 = bitcast ptr %a to ptr 2786 br label %bb1 2787 2788 bb1: 2789 %x = phi ptr [ %a32, %entry ], [ %r, %bb1 ] 2790 %r = getelementptr i32, ptr %x, i32 1 2791 br i1 %cond, label %bb1, label %exit 2792 2793 exit: 2794 ret void 2795 })", 2796 true, false}, 2797 2798 {R"( 2799 define void @test(i1 %cond, ptr %a) { 2800 entry: 2801 %r = bitcast ptr %a to ptr 2802 ret void 2803 })", 2804 false, false}, 2805 2806 {R"( 2807 define void @test(i1 %cond) { 2808 entry: 2809 %a = alloca i32 2810 %b = alloca i32 2811 br label %bb1 2812 2813 bb1: 2814 %r = phi ptr [ %a, %entry ], [ %b, %bb1 ] 2815 br i1 %cond, label %bb1, label %exit 2816 2817 exit: 2818 ret void 2819 })", 2820 false, false}, 2821 {R"( 2822 declare ptr @retptr(ptr returned) 2823 define void @test(i1 %cond) { 2824 %a = alloca i32 2825 %r = call ptr @retptr(ptr %a) 2826 ret void 2827 })", 2828 true, true}, 2829 {R"( 2830 declare ptr @fun(ptr) 2831 define void @test(i1 %cond) { 2832 %a = alloca i32 2833 %r = call ptr @fun(ptr %a) 2834 ret void 2835 })", 2836 false, false}, 2837 }; 2838 2839 TEST_P(FindAllocaForValueTest, findAllocaForValue) { 2840 auto M = parseModule(GetParam().IR); 2841 Function *F = M->getFunction("test"); 2842 Instruction *I = &findInstructionByName(F, "r"); 2843 const AllocaInst *AI = findAllocaForValue(I); 2844 EXPECT_EQ(!!AI, GetParam().AnyOffsetResult); 2845 } 2846 2847 TEST_P(FindAllocaForValueTest, findAllocaForValueZeroOffset) { 2848 auto M = parseModule(GetParam().IR); 2849 Function *F = M->getFunction("test"); 2850 Instruction *I = &findInstructionByName(F, "r"); 2851 const AllocaInst *AI = findAllocaForValue(I, true); 2852 EXPECT_EQ(!!AI, GetParam().ZeroOffsetResult); 2853 } 2854 2855 INSTANTIATE_TEST_SUITE_P(FindAllocaForValueTest, FindAllocaForValueTest, 2856 ::testing::ValuesIn(FindAllocaForValueTests)); 2857