1 //===- LoopInfoTest.cpp - LoopInfo unit 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/LoopInfo.h" 10 #include "llvm/Analysis/AssumptionCache.h" 11 #include "llvm/Analysis/PostDominators.h" 12 #include "llvm/Analysis/ScalarEvolution.h" 13 #include "llvm/Analysis/TargetLibraryInfo.h" 14 #include "llvm/AsmParser/Parser.h" 15 #include "llvm/IR/Dominators.h" 16 #include "llvm/Support/SourceMgr.h" 17 #include "gtest/gtest.h" 18 19 using namespace llvm; 20 21 /// Build the loop info for the function and run the Test. 22 static void 23 runWithLoopInfo(Module &M, StringRef FuncName, 24 function_ref<void(Function &F, LoopInfo &LI)> Test) { 25 auto *F = M.getFunction(FuncName); 26 ASSERT_NE(F, nullptr) << "Could not find " << FuncName; 27 // Compute the dominator tree and the loop info for the function. 28 DominatorTree DT(*F); 29 LoopInfo LI(DT); 30 Test(*F, LI); 31 } 32 33 /// Build the loop info and scalar evolution for the function and run the Test. 34 static void runWithLoopInfoPlus( 35 Module &M, StringRef FuncName, 36 function_ref<void(Function &F, LoopInfo &LI, ScalarEvolution &SE, 37 PostDominatorTree &PDT)> 38 Test) { 39 auto *F = M.getFunction(FuncName); 40 ASSERT_NE(F, nullptr) << "Could not find " << FuncName; 41 42 TargetLibraryInfoImpl TLII; 43 TargetLibraryInfo TLI(TLII); 44 AssumptionCache AC(*F); 45 DominatorTree DT(*F); 46 LoopInfo LI(DT); 47 ScalarEvolution SE(*F, TLI, AC, DT, LI); 48 49 PostDominatorTree PDT(*F); 50 Test(*F, LI, SE, PDT); 51 } 52 53 static std::unique_ptr<Module> makeLLVMModule(LLVMContext &Context, 54 const char *ModuleStr) { 55 SMDiagnostic Err; 56 return parseAssemblyString(ModuleStr, Err, Context); 57 } 58 59 // This tests that for a loop with a single latch, we get the loop id from 60 // its only latch, even in case the loop may not be in a simplified form. 61 TEST(LoopInfoTest, LoopWithSingleLatch) { 62 const char *ModuleStr = 63 "target datalayout = \"e-m:o-i64:64-f80:128-n8:16:32:64-S128\"\n" 64 "define void @foo(i32 %n) {\n" 65 "entry:\n" 66 " br i1 undef, label %for.cond, label %for.end\n" 67 "for.cond:\n" 68 " %i.0 = phi i32 [ 0, %entry ], [ %inc, %for.inc ]\n" 69 " %cmp = icmp slt i32 %i.0, %n\n" 70 " br i1 %cmp, label %for.inc, label %for.end\n" 71 "for.inc:\n" 72 " %inc = add nsw i32 %i.0, 1\n" 73 " br label %for.cond, !llvm.loop !0\n" 74 "for.end:\n" 75 " ret void\n" 76 "}\n" 77 "!0 = distinct !{!0, !1}\n" 78 "!1 = !{!\"llvm.loop.distribute.enable\", i1 true}\n"; 79 80 // Parse the module. 81 LLVMContext Context; 82 std::unique_ptr<Module> M = makeLLVMModule(Context, ModuleStr); 83 84 runWithLoopInfo(*M, "foo", [&](Function &F, LoopInfo &LI) { 85 Function::iterator FI = F.begin(); 86 // First basic block is entry - skip it. 87 BasicBlock *Header = &*(++FI); 88 assert(Header->getName() == "for.cond"); 89 Loop *L = LI.getLoopFor(Header); 90 91 // This loop is not in simplified form. 92 EXPECT_FALSE(L->isLoopSimplifyForm()); 93 94 // Analyze the loop metadata id. 95 bool loopIDFoundAndSet = false; 96 // Try to get and set the metadata id for the loop. 97 if (MDNode *D = L->getLoopID()) { 98 L->setLoopID(D); 99 loopIDFoundAndSet = true; 100 } 101 102 // We must have successfully found and set the loop id in the 103 // only latch the loop has. 104 EXPECT_TRUE(loopIDFoundAndSet); 105 }); 106 } 107 108 // Test loop id handling for a loop with multiple latches. 109 TEST(LoopInfoTest, LoopWithMultipleLatches) { 110 const char *ModuleStr = 111 "target datalayout = \"e-m:o-i64:64-f80:128-n8:16:32:64-S128\"\n" 112 "define void @foo(i32 %n) {\n" 113 "entry:\n" 114 " br i1 undef, label %for.cond, label %for.end\n" 115 "for.cond:\n" 116 " %i.0 = phi i32 [ 0, %entry ], [ %inc, %latch.1 ], [ %inc, %latch.2 ]\n" 117 " %inc = add nsw i32 %i.0, 1\n" 118 " %cmp = icmp slt i32 %i.0, %n\n" 119 " br i1 %cmp, label %latch.1, label %for.end\n" 120 "latch.1:\n" 121 " br i1 undef, label %for.cond, label %latch.2, !llvm.loop !0\n" 122 "latch.2:\n" 123 " br label %for.cond, !llvm.loop !0\n" 124 "for.end:\n" 125 " ret void\n" 126 "}\n" 127 "!0 = distinct !{!0, !1}\n" 128 "!1 = !{!\"llvm.loop.distribute.enable\", i1 true}\n"; 129 130 // Parse the module. 131 LLVMContext Context; 132 std::unique_ptr<Module> M = makeLLVMModule(Context, ModuleStr); 133 134 runWithLoopInfo(*M, "foo", [&](Function &F, LoopInfo &LI) { 135 Function::iterator FI = F.begin(); 136 // First basic block is entry - skip it. 137 BasicBlock *Header = &*(++FI); 138 assert(Header->getName() == "for.cond"); 139 Loop *L = LI.getLoopFor(Header); 140 EXPECT_NE(L, nullptr); 141 142 // This loop is not in simplified form. 143 EXPECT_FALSE(L->isLoopSimplifyForm()); 144 145 // Try to get and set the metadata id for the loop. 146 MDNode *OldLoopID = L->getLoopID(); 147 EXPECT_NE(OldLoopID, nullptr); 148 149 MDNode *NewLoopID = MDNode::get(Context, {nullptr}); 150 // Set operand 0 to refer to the loop id itself. 151 NewLoopID->replaceOperandWith(0, NewLoopID); 152 153 L->setLoopID(NewLoopID); 154 EXPECT_EQ(L->getLoopID(), NewLoopID); 155 EXPECT_NE(L->getLoopID(), OldLoopID); 156 157 L->setLoopID(OldLoopID); 158 EXPECT_EQ(L->getLoopID(), OldLoopID); 159 EXPECT_NE(L->getLoopID(), NewLoopID); 160 }); 161 } 162 163 TEST(LoopInfoTest, PreorderTraversals) { 164 const char *ModuleStr = "define void @f() {\n" 165 "entry:\n" 166 " br label %loop.0\n" 167 "loop.0:\n" 168 " br i1 undef, label %loop.0.0, label %loop.1\n" 169 "loop.0.0:\n" 170 " br i1 undef, label %loop.0.0, label %loop.0.1\n" 171 "loop.0.1:\n" 172 " br i1 undef, label %loop.0.1, label %loop.0.2\n" 173 "loop.0.2:\n" 174 " br i1 undef, label %loop.0.2, label %loop.0\n" 175 "loop.1:\n" 176 " br i1 undef, label %loop.1.0, label %end\n" 177 "loop.1.0:\n" 178 " br i1 undef, label %loop.1.0, label %loop.1.1\n" 179 "loop.1.1:\n" 180 " br i1 undef, label %loop.1.1, label %loop.1.2\n" 181 "loop.1.2:\n" 182 " br i1 undef, label %loop.1.2, label %loop.1\n" 183 "end:\n" 184 " ret void\n" 185 "}\n"; 186 // Parse the module. 187 LLVMContext Context; 188 std::unique_ptr<Module> M = makeLLVMModule(Context, ModuleStr); 189 Function &F = *M->begin(); 190 191 DominatorTree DT(F); 192 LoopInfo LI; 193 LI.analyze(DT); 194 195 Function::iterator I = F.begin(); 196 ASSERT_EQ("entry", I->getName()); 197 ++I; 198 Loop &L_0 = *LI.getLoopFor(&*I++); 199 ASSERT_EQ("loop.0", L_0.getHeader()->getName()); 200 Loop &L_0_0 = *LI.getLoopFor(&*I++); 201 ASSERT_EQ("loop.0.0", L_0_0.getHeader()->getName()); 202 Loop &L_0_1 = *LI.getLoopFor(&*I++); 203 ASSERT_EQ("loop.0.1", L_0_1.getHeader()->getName()); 204 Loop &L_0_2 = *LI.getLoopFor(&*I++); 205 ASSERT_EQ("loop.0.2", L_0_2.getHeader()->getName()); 206 Loop &L_1 = *LI.getLoopFor(&*I++); 207 ASSERT_EQ("loop.1", L_1.getHeader()->getName()); 208 Loop &L_1_0 = *LI.getLoopFor(&*I++); 209 ASSERT_EQ("loop.1.0", L_1_0.getHeader()->getName()); 210 Loop &L_1_1 = *LI.getLoopFor(&*I++); 211 ASSERT_EQ("loop.1.1", L_1_1.getHeader()->getName()); 212 Loop &L_1_2 = *LI.getLoopFor(&*I++); 213 ASSERT_EQ("loop.1.2", L_1_2.getHeader()->getName()); 214 215 auto Preorder = LI.getLoopsInPreorder(); 216 ASSERT_EQ(8u, Preorder.size()); 217 EXPECT_EQ(&L_0, Preorder[0]); 218 EXPECT_EQ(&L_0_0, Preorder[1]); 219 EXPECT_EQ(&L_0_1, Preorder[2]); 220 EXPECT_EQ(&L_0_2, Preorder[3]); 221 EXPECT_EQ(&L_1, Preorder[4]); 222 EXPECT_EQ(&L_1_0, Preorder[5]); 223 EXPECT_EQ(&L_1_1, Preorder[6]); 224 EXPECT_EQ(&L_1_2, Preorder[7]); 225 226 auto ReverseSiblingPreorder = LI.getLoopsInReverseSiblingPreorder(); 227 ASSERT_EQ(8u, ReverseSiblingPreorder.size()); 228 EXPECT_EQ(&L_1, ReverseSiblingPreorder[0]); 229 EXPECT_EQ(&L_1_2, ReverseSiblingPreorder[1]); 230 EXPECT_EQ(&L_1_1, ReverseSiblingPreorder[2]); 231 EXPECT_EQ(&L_1_0, ReverseSiblingPreorder[3]); 232 EXPECT_EQ(&L_0, ReverseSiblingPreorder[4]); 233 EXPECT_EQ(&L_0_2, ReverseSiblingPreorder[5]); 234 EXPECT_EQ(&L_0_1, ReverseSiblingPreorder[6]); 235 EXPECT_EQ(&L_0_0, ReverseSiblingPreorder[7]); 236 } 237 238 TEST(LoopInfoTest, CanonicalLoop) { 239 const char *ModuleStr = 240 "define void @foo(i32* %A, i32 %ub) {\n" 241 "entry:\n" 242 " %guardcmp = icmp slt i32 0, %ub\n" 243 " br i1 %guardcmp, label %for.preheader, label %for.end\n" 244 "for.preheader:\n" 245 " br label %for.body\n" 246 "for.body:\n" 247 " %i = phi i32 [ 0, %for.preheader ], [ %inc, %for.body ]\n" 248 " %idxprom = sext i32 %i to i64\n" 249 " %arrayidx = getelementptr inbounds i32, i32* %A, i64 %idxprom\n" 250 " store i32 %i, i32* %arrayidx, align 4\n" 251 " %inc = add nsw i32 %i, 1\n" 252 " %cmp = icmp slt i32 %inc, %ub\n" 253 " br i1 %cmp, label %for.body, label %for.exit\n" 254 "for.exit:\n" 255 " br label %for.end\n" 256 "for.end:\n" 257 " ret void\n" 258 "}\n"; 259 260 // Parse the module. 261 LLVMContext Context; 262 std::unique_ptr<Module> M = makeLLVMModule(Context, ModuleStr); 263 264 runWithLoopInfoPlus( 265 *M, "foo", 266 [&](Function &F, LoopInfo &LI, ScalarEvolution &SE, 267 PostDominatorTree &PDT) { 268 Function::iterator FI = F.begin(); 269 // First two basic block are entry and for.preheader - skip them. 270 ++FI; 271 BasicBlock *Header = &*(++FI); 272 assert(Header->getName() == "for.body"); 273 Loop *L = LI.getLoopFor(Header); 274 EXPECT_NE(L, nullptr); 275 276 Optional<Loop::LoopBounds> Bounds = L->getBounds(SE); 277 EXPECT_NE(Bounds, None); 278 ConstantInt *InitialIVValue = 279 dyn_cast<ConstantInt>(&Bounds->getInitialIVValue()); 280 EXPECT_TRUE(InitialIVValue && InitialIVValue->isZero()); 281 EXPECT_EQ(Bounds->getStepInst().getName(), "inc"); 282 ConstantInt *StepValue = 283 dyn_cast_or_null<ConstantInt>(Bounds->getStepValue()); 284 EXPECT_TRUE(StepValue && StepValue->isOne()); 285 EXPECT_EQ(Bounds->getFinalIVValue().getName(), "ub"); 286 EXPECT_EQ(Bounds->getCanonicalPredicate(), ICmpInst::ICMP_SLT); 287 EXPECT_EQ(Bounds->getDirection(), 288 Loop::LoopBounds::Direction::Increasing); 289 EXPECT_EQ(L->getInductionVariable(SE)->getName(), "i"); 290 }); 291 } 292 293 TEST(LoopInfoTest, LoopWithInverseGuardSuccs) { 294 const char *ModuleStr = 295 "define void @foo(i32* %A, i32 %ub) {\n" 296 "entry:\n" 297 " %guardcmp = icmp sge i32 0, %ub\n" 298 " br i1 %guardcmp, label %for.end, label %for.preheader\n" 299 "for.preheader:\n" 300 " br label %for.body\n" 301 "for.body:\n" 302 " %i = phi i32 [ 0, %for.preheader ], [ %inc, %for.body ]\n" 303 " %idxprom = sext i32 %i to i64\n" 304 " %arrayidx = getelementptr inbounds i32, i32* %A, i64 %idxprom\n" 305 " store i32 %i, i32* %arrayidx, align 4\n" 306 " %inc = add nsw i32 %i, 1\n" 307 " %cmp = icmp slt i32 %inc, %ub\n" 308 " br i1 %cmp, label %for.body, label %for.exit\n" 309 "for.exit:\n" 310 " br label %for.end\n" 311 "for.end:\n" 312 " ret void\n" 313 "}\n"; 314 315 // Parse the module. 316 LLVMContext Context; 317 std::unique_ptr<Module> M = makeLLVMModule(Context, ModuleStr); 318 319 runWithLoopInfoPlus( 320 *M, "foo", 321 [&](Function &F, LoopInfo &LI, ScalarEvolution &SE, 322 PostDominatorTree &PDT) { 323 Function::iterator FI = F.begin(); 324 // First two basic block are entry and for.preheader - skip them. 325 ++FI; 326 BasicBlock *Header = &*(++FI); 327 assert(Header->getName() == "for.body"); 328 Loop *L = LI.getLoopFor(Header); 329 EXPECT_NE(L, nullptr); 330 331 Optional<Loop::LoopBounds> Bounds = L->getBounds(SE); 332 EXPECT_NE(Bounds, None); 333 ConstantInt *InitialIVValue = 334 dyn_cast<ConstantInt>(&Bounds->getInitialIVValue()); 335 EXPECT_TRUE(InitialIVValue && InitialIVValue->isZero()); 336 EXPECT_EQ(Bounds->getStepInst().getName(), "inc"); 337 ConstantInt *StepValue = 338 dyn_cast_or_null<ConstantInt>(Bounds->getStepValue()); 339 EXPECT_TRUE(StepValue && StepValue->isOne()); 340 EXPECT_EQ(Bounds->getFinalIVValue().getName(), "ub"); 341 EXPECT_EQ(Bounds->getCanonicalPredicate(), ICmpInst::ICMP_SLT); 342 EXPECT_EQ(Bounds->getDirection(), 343 Loop::LoopBounds::Direction::Increasing); 344 EXPECT_EQ(L->getInductionVariable(SE)->getName(), "i"); 345 }); 346 } 347 348 TEST(LoopInfoTest, LoopWithSwappedGuardCmp) { 349 const char *ModuleStr = 350 "define void @foo(i32* %A, i32 %ub) {\n" 351 "entry:\n" 352 " %guardcmp = icmp sgt i32 %ub, 0\n" 353 " br i1 %guardcmp, label %for.preheader, label %for.end\n" 354 "for.preheader:\n" 355 " br label %for.body\n" 356 "for.body:\n" 357 " %i = phi i32 [ 0, %for.preheader ], [ %inc, %for.body ]\n" 358 " %idxprom = sext i32 %i to i64\n" 359 " %arrayidx = getelementptr inbounds i32, i32* %A, i64 %idxprom\n" 360 " store i32 %i, i32* %arrayidx, align 4\n" 361 " %inc = add nsw i32 %i, 1\n" 362 " %cmp = icmp sge i32 %inc, %ub\n" 363 " br i1 %cmp, label %for.exit, label %for.body\n" 364 "for.exit:\n" 365 " br label %for.end\n" 366 "for.end:\n" 367 " ret void\n" 368 "}\n"; 369 370 // Parse the module. 371 LLVMContext Context; 372 std::unique_ptr<Module> M = makeLLVMModule(Context, ModuleStr); 373 374 runWithLoopInfoPlus( 375 *M, "foo", 376 [&](Function &F, LoopInfo &LI, ScalarEvolution &SE, 377 PostDominatorTree &PDT) { 378 Function::iterator FI = F.begin(); 379 // First two basic block are entry and for.preheader - skip them. 380 ++FI; 381 BasicBlock *Header = &*(++FI); 382 assert(Header->getName() == "for.body"); 383 Loop *L = LI.getLoopFor(Header); 384 EXPECT_NE(L, nullptr); 385 386 Optional<Loop::LoopBounds> Bounds = L->getBounds(SE); 387 EXPECT_NE(Bounds, None); 388 ConstantInt *InitialIVValue = 389 dyn_cast<ConstantInt>(&Bounds->getInitialIVValue()); 390 EXPECT_TRUE(InitialIVValue && InitialIVValue->isZero()); 391 EXPECT_EQ(Bounds->getStepInst().getName(), "inc"); 392 ConstantInt *StepValue = 393 dyn_cast_or_null<ConstantInt>(Bounds->getStepValue()); 394 EXPECT_TRUE(StepValue && StepValue->isOne()); 395 EXPECT_EQ(Bounds->getFinalIVValue().getName(), "ub"); 396 EXPECT_EQ(Bounds->getCanonicalPredicate(), ICmpInst::ICMP_SLT); 397 EXPECT_EQ(Bounds->getDirection(), 398 Loop::LoopBounds::Direction::Increasing); 399 EXPECT_EQ(L->getInductionVariable(SE)->getName(), "i"); 400 }); 401 } 402 403 TEST(LoopInfoTest, LoopWithInverseLatchSuccs) { 404 const char *ModuleStr = 405 "define void @foo(i32* %A, i32 %ub) {\n" 406 "entry:\n" 407 " %guardcmp = icmp slt i32 0, %ub\n" 408 " br i1 %guardcmp, label %for.preheader, label %for.end\n" 409 "for.preheader:\n" 410 " br label %for.body\n" 411 "for.body:\n" 412 " %i = phi i32 [ 0, %for.preheader ], [ %inc, %for.body ]\n" 413 " %idxprom = sext i32 %i to i64\n" 414 " %arrayidx = getelementptr inbounds i32, i32* %A, i64 %idxprom\n" 415 " store i32 %i, i32* %arrayidx, align 4\n" 416 " %inc = add nsw i32 %i, 1\n" 417 " %cmp = icmp sge i32 %inc, %ub\n" 418 " br i1 %cmp, label %for.exit, label %for.body\n" 419 "for.exit:\n" 420 " br label %for.end\n" 421 "for.end:\n" 422 " ret void\n" 423 "}\n"; 424 425 // Parse the module. 426 LLVMContext Context; 427 std::unique_ptr<Module> M = makeLLVMModule(Context, ModuleStr); 428 429 runWithLoopInfoPlus( 430 *M, "foo", 431 [&](Function &F, LoopInfo &LI, ScalarEvolution &SE, 432 PostDominatorTree &PDT) { 433 Function::iterator FI = F.begin(); 434 // First two basic block are entry and for.preheader - skip them. 435 ++FI; 436 BasicBlock *Header = &*(++FI); 437 assert(Header->getName() == "for.body"); 438 Loop *L = LI.getLoopFor(Header); 439 EXPECT_NE(L, nullptr); 440 441 Optional<Loop::LoopBounds> Bounds = L->getBounds(SE); 442 EXPECT_NE(Bounds, None); 443 ConstantInt *InitialIVValue = 444 dyn_cast<ConstantInt>(&Bounds->getInitialIVValue()); 445 EXPECT_TRUE(InitialIVValue && InitialIVValue->isZero()); 446 EXPECT_EQ(Bounds->getStepInst().getName(), "inc"); 447 ConstantInt *StepValue = 448 dyn_cast_or_null<ConstantInt>(Bounds->getStepValue()); 449 EXPECT_TRUE(StepValue && StepValue->isOne()); 450 EXPECT_EQ(Bounds->getFinalIVValue().getName(), "ub"); 451 EXPECT_EQ(Bounds->getCanonicalPredicate(), ICmpInst::ICMP_SLT); 452 EXPECT_EQ(Bounds->getDirection(), 453 Loop::LoopBounds::Direction::Increasing); 454 EXPECT_EQ(L->getInductionVariable(SE)->getName(), "i"); 455 }); 456 } 457 458 TEST(LoopInfoTest, LoopWithLatchCmpNE) { 459 const char *ModuleStr = 460 "define void @foo(i32* %A, i32 %ub) {\n" 461 "entry:\n" 462 " %guardcmp = icmp slt i32 0, %ub\n" 463 " br i1 %guardcmp, label %for.preheader, label %for.end\n" 464 "for.preheader:\n" 465 " br label %for.body\n" 466 "for.body:\n" 467 " %i = phi i32 [ 0, %for.preheader ], [ %inc, %for.body ]\n" 468 " %idxprom = sext i32 %i to i64\n" 469 " %arrayidx = getelementptr inbounds i32, i32* %A, i64 %idxprom\n" 470 " store i32 %i, i32* %arrayidx, align 4\n" 471 " %inc = add nsw i32 %i, 1\n" 472 " %cmp = icmp ne i32 %i, %ub\n" 473 " br i1 %cmp, label %for.body, label %for.exit\n" 474 "for.exit:\n" 475 " br label %for.end\n" 476 "for.end:\n" 477 " ret void\n" 478 "}\n"; 479 480 // Parse the module. 481 LLVMContext Context; 482 std::unique_ptr<Module> M = makeLLVMModule(Context, ModuleStr); 483 484 runWithLoopInfoPlus( 485 *M, "foo", 486 [&](Function &F, LoopInfo &LI, ScalarEvolution &SE, 487 PostDominatorTree &PDT) { 488 Function::iterator FI = F.begin(); 489 // First two basic block are entry and for.preheader - skip them. 490 ++FI; 491 BasicBlock *Header = &*(++FI); 492 assert(Header->getName() == "for.body"); 493 Loop *L = LI.getLoopFor(Header); 494 EXPECT_NE(L, nullptr); 495 496 Optional<Loop::LoopBounds> Bounds = L->getBounds(SE); 497 EXPECT_NE(Bounds, None); 498 ConstantInt *InitialIVValue = 499 dyn_cast<ConstantInt>(&Bounds->getInitialIVValue()); 500 EXPECT_TRUE(InitialIVValue && InitialIVValue->isZero()); 501 EXPECT_EQ(Bounds->getStepInst().getName(), "inc"); 502 ConstantInt *StepValue = 503 dyn_cast_or_null<ConstantInt>(Bounds->getStepValue()); 504 EXPECT_TRUE(StepValue && StepValue->isOne()); 505 EXPECT_EQ(Bounds->getFinalIVValue().getName(), "ub"); 506 EXPECT_EQ(Bounds->getCanonicalPredicate(), ICmpInst::ICMP_SLT); 507 EXPECT_EQ(Bounds->getDirection(), 508 Loop::LoopBounds::Direction::Increasing); 509 EXPECT_EQ(L->getInductionVariable(SE)->getName(), "i"); 510 }); 511 } 512 513 TEST(LoopInfoTest, LoopWithGuardCmpSLE) { 514 const char *ModuleStr = 515 "define void @foo(i32* %A, i32 %ub) {\n" 516 "entry:\n" 517 " %ubPlusOne = add i32 %ub, 1\n" 518 " %guardcmp = icmp sle i32 0, %ub\n" 519 " br i1 %guardcmp, label %for.preheader, label %for.end\n" 520 "for.preheader:\n" 521 " br label %for.body\n" 522 "for.body:\n" 523 " %i = phi i32 [ 0, %for.preheader ], [ %inc, %for.body ]\n" 524 " %idxprom = sext i32 %i to i64\n" 525 " %arrayidx = getelementptr inbounds i32, i32* %A, i64 %idxprom\n" 526 " store i32 %i, i32* %arrayidx, align 4\n" 527 " %inc = add nsw i32 %i, 1\n" 528 " %cmp = icmp ne i32 %i, %ubPlusOne\n" 529 " br i1 %cmp, label %for.body, label %for.exit\n" 530 "for.exit:\n" 531 " br label %for.end\n" 532 "for.end:\n" 533 " ret void\n" 534 "}\n"; 535 536 // Parse the module. 537 LLVMContext Context; 538 std::unique_ptr<Module> M = makeLLVMModule(Context, ModuleStr); 539 540 runWithLoopInfoPlus( 541 *M, "foo", 542 [&](Function &F, LoopInfo &LI, ScalarEvolution &SE, 543 PostDominatorTree &PDT) { 544 Function::iterator FI = F.begin(); 545 // First two basic block are entry and for.preheader - skip them. 546 ++FI; 547 BasicBlock *Header = &*(++FI); 548 assert(Header->getName() == "for.body"); 549 Loop *L = LI.getLoopFor(Header); 550 EXPECT_NE(L, nullptr); 551 552 Optional<Loop::LoopBounds> Bounds = L->getBounds(SE); 553 EXPECT_NE(Bounds, None); 554 ConstantInt *InitialIVValue = 555 dyn_cast<ConstantInt>(&Bounds->getInitialIVValue()); 556 EXPECT_TRUE(InitialIVValue && InitialIVValue->isZero()); 557 EXPECT_EQ(Bounds->getStepInst().getName(), "inc"); 558 ConstantInt *StepValue = 559 dyn_cast_or_null<ConstantInt>(Bounds->getStepValue()); 560 EXPECT_TRUE(StepValue && StepValue->isOne()); 561 EXPECT_EQ(Bounds->getFinalIVValue().getName(), "ubPlusOne"); 562 EXPECT_EQ(Bounds->getCanonicalPredicate(), ICmpInst::ICMP_SLT); 563 EXPECT_EQ(Bounds->getDirection(), 564 Loop::LoopBounds::Direction::Increasing); 565 EXPECT_EQ(L->getInductionVariable(SE)->getName(), "i"); 566 }); 567 } 568 569 TEST(LoopInfoTest, LoopNonConstantStep) { 570 const char *ModuleStr = 571 "define void @foo(i32* %A, i32 %ub, i32 %step) {\n" 572 "entry:\n" 573 " %guardcmp = icmp slt i32 0, %ub\n" 574 " br i1 %guardcmp, label %for.preheader, label %for.end\n" 575 "for.preheader:\n" 576 " br label %for.body\n" 577 "for.body:\n" 578 " %i = phi i32 [ 0, %for.preheader ], [ %inc, %for.body ]\n" 579 " %idxprom = zext i32 %i to i64\n" 580 " %arrayidx = getelementptr inbounds i32, i32* %A, i64 %idxprom\n" 581 " store i32 %i, i32* %arrayidx, align 4\n" 582 " %inc = add nsw i32 %i, %step\n" 583 " %cmp = icmp slt i32 %inc, %ub\n" 584 " br i1 %cmp, label %for.body, label %for.exit\n" 585 "for.exit:\n" 586 " br label %for.end\n" 587 "for.end:\n" 588 " ret void\n" 589 "}\n"; 590 591 // Parse the module. 592 LLVMContext Context; 593 std::unique_ptr<Module> M = makeLLVMModule(Context, ModuleStr); 594 595 runWithLoopInfoPlus( 596 *M, "foo", 597 [&](Function &F, LoopInfo &LI, ScalarEvolution &SE, 598 PostDominatorTree &PDT) { 599 Function::iterator FI = F.begin(); 600 // First two basic block are entry and for.preheader - skip them. 601 ++FI; 602 BasicBlock *Header = &*(++FI); 603 assert(Header->getName() == "for.body"); 604 Loop *L = LI.getLoopFor(Header); 605 EXPECT_NE(L, nullptr); 606 607 Optional<Loop::LoopBounds> Bounds = L->getBounds(SE); 608 EXPECT_NE(Bounds, None); 609 ConstantInt *InitialIVValue = 610 dyn_cast<ConstantInt>(&Bounds->getInitialIVValue()); 611 EXPECT_TRUE(InitialIVValue && InitialIVValue->isZero()); 612 EXPECT_EQ(Bounds->getStepInst().getName(), "inc"); 613 EXPECT_EQ(Bounds->getStepValue()->getName(), "step"); 614 EXPECT_EQ(Bounds->getFinalIVValue().getName(), "ub"); 615 EXPECT_EQ(Bounds->getCanonicalPredicate(), ICmpInst::ICMP_SLT); 616 EXPECT_EQ(Bounds->getDirection(), Loop::LoopBounds::Direction::Unknown); 617 EXPECT_EQ(L->getInductionVariable(SE)->getName(), "i"); 618 }); 619 } 620 621 TEST(LoopInfoTest, LoopUnsignedBounds) { 622 const char *ModuleStr = 623 "define void @foo(i32* %A, i32 %ub) {\n" 624 "entry:\n" 625 " %guardcmp = icmp ult i32 0, %ub\n" 626 " br i1 %guardcmp, label %for.preheader, label %for.end\n" 627 "for.preheader:\n" 628 " br label %for.body\n" 629 "for.body:\n" 630 " %i = phi i32 [ 0, %for.preheader ], [ %inc, %for.body ]\n" 631 " %idxprom = zext i32 %i to i64\n" 632 " %arrayidx = getelementptr inbounds i32, i32* %A, i64 %idxprom\n" 633 " store i32 %i, i32* %arrayidx, align 4\n" 634 " %inc = add i32 %i, 1\n" 635 " %cmp = icmp ult i32 %inc, %ub\n" 636 " br i1 %cmp, label %for.body, label %for.exit\n" 637 "for.exit:\n" 638 " br label %for.end\n" 639 "for.end:\n" 640 " ret void\n" 641 "}\n"; 642 643 // Parse the module. 644 LLVMContext Context; 645 std::unique_ptr<Module> M = makeLLVMModule(Context, ModuleStr); 646 647 runWithLoopInfoPlus( 648 *M, "foo", 649 [&](Function &F, LoopInfo &LI, ScalarEvolution &SE, 650 PostDominatorTree &PDT) { 651 Function::iterator FI = F.begin(); 652 // First two basic block are entry and for.preheader - skip them. 653 ++FI; 654 BasicBlock *Header = &*(++FI); 655 assert(Header->getName() == "for.body"); 656 Loop *L = LI.getLoopFor(Header); 657 EXPECT_NE(L, nullptr); 658 659 Optional<Loop::LoopBounds> Bounds = L->getBounds(SE); 660 EXPECT_NE(Bounds, None); 661 ConstantInt *InitialIVValue = 662 dyn_cast<ConstantInt>(&Bounds->getInitialIVValue()); 663 EXPECT_TRUE(InitialIVValue && InitialIVValue->isZero()); 664 EXPECT_EQ(Bounds->getStepInst().getName(), "inc"); 665 ConstantInt *StepValue = 666 dyn_cast_or_null<ConstantInt>(Bounds->getStepValue()); 667 EXPECT_TRUE(StepValue && StepValue->isOne()); 668 EXPECT_EQ(Bounds->getFinalIVValue().getName(), "ub"); 669 EXPECT_EQ(Bounds->getCanonicalPredicate(), ICmpInst::ICMP_ULT); 670 EXPECT_EQ(Bounds->getDirection(), 671 Loop::LoopBounds::Direction::Increasing); 672 EXPECT_EQ(L->getInductionVariable(SE)->getName(), "i"); 673 }); 674 } 675 676 TEST(LoopInfoTest, DecreasingLoop) { 677 const char *ModuleStr = 678 "define void @foo(i32* %A, i32 %ub) {\n" 679 "entry:\n" 680 " %guardcmp = icmp slt i32 0, %ub\n" 681 " br i1 %guardcmp, label %for.preheader, label %for.end\n" 682 "for.preheader:\n" 683 " br label %for.body\n" 684 "for.body:\n" 685 " %i = phi i32 [ %ub, %for.preheader ], [ %inc, %for.body ]\n" 686 " %idxprom = sext i32 %i to i64\n" 687 " %arrayidx = getelementptr inbounds i32, i32* %A, i64 %idxprom\n" 688 " store i32 %i, i32* %arrayidx, align 4\n" 689 " %inc = sub nsw i32 %i, 1\n" 690 " %cmp = icmp sgt i32 %inc, 0\n" 691 " br i1 %cmp, label %for.body, label %for.exit\n" 692 "for.exit:\n" 693 " br label %for.end\n" 694 "for.end:\n" 695 " ret void\n" 696 "}\n"; 697 698 // Parse the module. 699 LLVMContext Context; 700 std::unique_ptr<Module> M = makeLLVMModule(Context, ModuleStr); 701 702 runWithLoopInfoPlus( 703 *M, "foo", 704 [&](Function &F, LoopInfo &LI, ScalarEvolution &SE, 705 PostDominatorTree &PDT) { 706 Function::iterator FI = F.begin(); 707 // First two basic block are entry and for.preheader - skip them. 708 ++FI; 709 BasicBlock *Header = &*(++FI); 710 assert(Header->getName() == "for.body"); 711 Loop *L = LI.getLoopFor(Header); 712 EXPECT_NE(L, nullptr); 713 714 Optional<Loop::LoopBounds> Bounds = L->getBounds(SE); 715 EXPECT_NE(Bounds, None); 716 EXPECT_EQ(Bounds->getInitialIVValue().getName(), "ub"); 717 EXPECT_EQ(Bounds->getStepInst().getName(), "inc"); 718 ConstantInt *StepValue = 719 dyn_cast_or_null<ConstantInt>(Bounds->getStepValue()); 720 EXPECT_EQ(StepValue, nullptr); 721 ConstantInt *FinalIVValue = 722 dyn_cast<ConstantInt>(&Bounds->getFinalIVValue()); 723 EXPECT_TRUE(FinalIVValue && FinalIVValue->isZero()); 724 EXPECT_EQ(Bounds->getCanonicalPredicate(), ICmpInst::ICMP_SGT); 725 EXPECT_EQ(Bounds->getDirection(), 726 Loop::LoopBounds::Direction::Decreasing); 727 EXPECT_EQ(L->getInductionVariable(SE)->getName(), "i"); 728 }); 729 } 730 731 TEST(LoopInfoTest, CannotFindDirection) { 732 const char *ModuleStr = 733 "define void @foo(i32* %A, i32 %ub, i32 %step) {\n" 734 "entry:\n" 735 " %guardcmp = icmp slt i32 0, %ub\n" 736 " br i1 %guardcmp, label %for.preheader, label %for.end\n" 737 "for.preheader:\n" 738 " br label %for.body\n" 739 "for.body:\n" 740 " %i = phi i32 [ 0, %for.preheader ], [ %inc, %for.body ]\n" 741 " %idxprom = sext i32 %i to i64\n" 742 " %arrayidx = getelementptr inbounds i32, i32* %A, i64 %idxprom\n" 743 " store i32 %i, i32* %arrayidx, align 4\n" 744 " %inc = add nsw i32 %i, %step\n" 745 " %cmp = icmp ne i32 %i, %ub\n" 746 " br i1 %cmp, label %for.body, label %for.exit\n" 747 "for.exit:\n" 748 " br label %for.end\n" 749 "for.end:\n" 750 " ret void\n" 751 "}\n"; 752 753 // Parse the module. 754 LLVMContext Context; 755 std::unique_ptr<Module> M = makeLLVMModule(Context, ModuleStr); 756 757 runWithLoopInfoPlus(*M, "foo", 758 [&](Function &F, LoopInfo &LI, ScalarEvolution &SE, 759 PostDominatorTree &PDT) { 760 Function::iterator FI = F.begin(); 761 // First two basic block are entry and for.preheader 762 // - skip them. 763 ++FI; 764 BasicBlock *Header = &*(++FI); 765 assert(Header->getName() == "for.body"); 766 Loop *L = LI.getLoopFor(Header); 767 EXPECT_NE(L, nullptr); 768 769 Optional<Loop::LoopBounds> Bounds = L->getBounds(SE); 770 EXPECT_NE(Bounds, None); 771 ConstantInt *InitialIVValue = 772 dyn_cast<ConstantInt>(&Bounds->getInitialIVValue()); 773 EXPECT_TRUE(InitialIVValue && InitialIVValue->isZero()); 774 EXPECT_EQ(Bounds->getStepInst().getName(), "inc"); 775 EXPECT_EQ(Bounds->getStepValue()->getName(), "step"); 776 EXPECT_EQ(Bounds->getFinalIVValue().getName(), "ub"); 777 EXPECT_EQ(Bounds->getCanonicalPredicate(), 778 ICmpInst::BAD_ICMP_PREDICATE); 779 EXPECT_EQ(Bounds->getDirection(), 780 Loop::LoopBounds::Direction::Unknown); 781 EXPECT_EQ(L->getInductionVariable(SE)->getName(), "i"); 782 }); 783 } 784 785 TEST(LoopInfoTest, ZextIndVar) { 786 const char *ModuleStr = 787 "define void @foo(i32* %A, i32 %ub) {\n" 788 "entry:\n" 789 " %guardcmp = icmp slt i32 0, %ub\n" 790 " br i1 %guardcmp, label %for.preheader, label %for.end\n" 791 "for.preheader:\n" 792 " br label %for.body\n" 793 "for.body:\n" 794 " %indvars.iv = phi i64 [ 0, %for.preheader ], [ %indvars.iv.next, %for.body ]\n" 795 " %i = phi i32 [ 0, %for.preheader ], [ %inc, %for.body ]\n" 796 " %idxprom = sext i32 %i to i64\n" 797 " %arrayidx = getelementptr inbounds i32, i32* %A, i64 %idxprom\n" 798 " store i32 %i, i32* %arrayidx, align 4\n" 799 " %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1\n" 800 " %inc = add nsw i32 %i, 1\n" 801 " %wide.trip.count = zext i32 %ub to i64\n" 802 " %exitcond = icmp ne i64 %indvars.iv.next, %wide.trip.count\n" 803 " br i1 %exitcond, label %for.body, label %for.exit\n" 804 "for.exit:\n" 805 " br label %for.end\n" 806 "for.end:\n" 807 " ret void\n" 808 "}\n"; 809 810 // Parse the module. 811 LLVMContext Context; 812 std::unique_ptr<Module> M = makeLLVMModule(Context, ModuleStr); 813 814 runWithLoopInfoPlus( 815 *M, "foo", 816 [&](Function &F, LoopInfo &LI, ScalarEvolution &SE, 817 PostDominatorTree &PDT) { 818 Function::iterator FI = F.begin(); 819 // First two basic block are entry and for.preheader - skip them. 820 ++FI; 821 BasicBlock *Header = &*(++FI); 822 assert(Header->getName() == "for.body"); 823 Loop *L = LI.getLoopFor(Header); 824 EXPECT_NE(L, nullptr); 825 826 Optional<Loop::LoopBounds> Bounds = L->getBounds(SE); 827 EXPECT_NE(Bounds, None); 828 ConstantInt *InitialIVValue = 829 dyn_cast<ConstantInt>(&Bounds->getInitialIVValue()); 830 EXPECT_TRUE(InitialIVValue && InitialIVValue->isZero()); 831 EXPECT_EQ(Bounds->getStepInst().getName(), "indvars.iv.next"); 832 ConstantInt *StepValue = 833 dyn_cast_or_null<ConstantInt>(Bounds->getStepValue()); 834 EXPECT_TRUE(StepValue && StepValue->isOne()); 835 EXPECT_EQ(Bounds->getFinalIVValue().getName(), "wide.trip.count"); 836 EXPECT_EQ(Bounds->getCanonicalPredicate(), ICmpInst::ICMP_NE); 837 EXPECT_EQ(Bounds->getDirection(), 838 Loop::LoopBounds::Direction::Increasing); 839 EXPECT_EQ(L->getInductionVariable(SE)->getName(), "indvars.iv"); 840 }); 841 } 842 843 TEST(LoopInfoTest, UnguardedLoop) { 844 const char *ModuleStr = 845 "define void @foo(i32* %A, i32 %ub) {\n" 846 "entry:\n" 847 " br label %for.body\n" 848 "for.body:\n" 849 " %i = phi i32 [ 0, %entry ], [ %inc, %for.body ]\n" 850 " %idxprom = sext i32 %i to i64\n" 851 " %arrayidx = getelementptr inbounds i32, i32* %A, i64 %idxprom\n" 852 " store i32 %i, i32* %arrayidx, align 4\n" 853 " %inc = add nsw i32 %i, 1\n" 854 " %cmp = icmp slt i32 %inc, %ub\n" 855 " br i1 %cmp, label %for.body, label %for.exit\n" 856 "for.exit:\n" 857 " br label %for.end\n" 858 "for.end:\n" 859 " ret void\n" 860 "}\n"; 861 862 // Parse the module. 863 LLVMContext Context; 864 std::unique_ptr<Module> M = makeLLVMModule(Context, ModuleStr); 865 866 runWithLoopInfoPlus( 867 *M, "foo", 868 [&](Function &F, LoopInfo &LI, ScalarEvolution &SE, 869 PostDominatorTree &PDT) { 870 Function::iterator FI = F.begin(); 871 // First basic block is entry - skip it. 872 BasicBlock *Header = &*(++FI); 873 assert(Header->getName() == "for.body"); 874 Loop *L = LI.getLoopFor(Header); 875 EXPECT_NE(L, nullptr); 876 877 Optional<Loop::LoopBounds> Bounds = L->getBounds(SE); 878 EXPECT_NE(Bounds, None); 879 ConstantInt *InitialIVValue = 880 dyn_cast<ConstantInt>(&Bounds->getInitialIVValue()); 881 EXPECT_TRUE(InitialIVValue && InitialIVValue->isZero()); 882 EXPECT_EQ(Bounds->getStepInst().getName(), "inc"); 883 ConstantInt *StepValue = 884 dyn_cast_or_null<ConstantInt>(Bounds->getStepValue()); 885 EXPECT_TRUE(StepValue && StepValue->isOne()); 886 EXPECT_EQ(Bounds->getFinalIVValue().getName(), "ub"); 887 EXPECT_EQ(Bounds->getCanonicalPredicate(), ICmpInst::ICMP_SLT); 888 EXPECT_EQ(Bounds->getDirection(), 889 Loop::LoopBounds::Direction::Increasing); 890 EXPECT_EQ(L->getInductionVariable(SE)->getName(), "i"); 891 }); 892 } 893 894 TEST(LoopInfoTest, UnguardedLoopWithControlFlow) { 895 const char *ModuleStr = 896 "define void @foo(i32* %A, i32 %ub, i1 %cond) {\n" 897 "entry:\n" 898 " br i1 %cond, label %for.preheader, label %for.end\n" 899 "for.preheader:\n" 900 " br label %for.body\n" 901 "for.body:\n" 902 " %i = phi i32 [ 0, %for.preheader ], [ %inc, %for.body ]\n" 903 " %idxprom = sext i32 %i to i64\n" 904 " %arrayidx = getelementptr inbounds i32, i32* %A, i64 %idxprom\n" 905 " store i32 %i, i32* %arrayidx, align 4\n" 906 " %inc = add nsw i32 %i, 1\n" 907 " %cmp = icmp slt i32 %inc, %ub\n" 908 " br i1 %cmp, label %for.body, label %for.exit\n" 909 "for.exit:\n" 910 " br label %for.end\n" 911 "for.end:\n" 912 " ret void\n" 913 "}\n"; 914 915 // Parse the module. 916 LLVMContext Context; 917 std::unique_ptr<Module> M = makeLLVMModule(Context, ModuleStr); 918 919 runWithLoopInfoPlus( 920 *M, "foo", 921 [&](Function &F, LoopInfo &LI, ScalarEvolution &SE, 922 PostDominatorTree &PDT) { 923 Function::iterator FI = F.begin(); 924 // First two basic block are entry and for.preheader - skip them. 925 ++FI; 926 BasicBlock *Header = &*(++FI); 927 assert(Header->getName() == "for.body"); 928 Loop *L = LI.getLoopFor(Header); 929 EXPECT_NE(L, nullptr); 930 931 Optional<Loop::LoopBounds> Bounds = L->getBounds(SE); 932 EXPECT_NE(Bounds, None); 933 ConstantInt *InitialIVValue = 934 dyn_cast<ConstantInt>(&Bounds->getInitialIVValue()); 935 EXPECT_TRUE(InitialIVValue && InitialIVValue->isZero()); 936 EXPECT_EQ(Bounds->getStepInst().getName(), "inc"); 937 ConstantInt *StepValue = 938 dyn_cast_or_null<ConstantInt>(Bounds->getStepValue()); 939 EXPECT_TRUE(StepValue && StepValue->isOne()); 940 EXPECT_EQ(Bounds->getFinalIVValue().getName(), "ub"); 941 EXPECT_EQ(Bounds->getCanonicalPredicate(), ICmpInst::ICMP_SLT); 942 EXPECT_EQ(Bounds->getDirection(), 943 Loop::LoopBounds::Direction::Increasing); 944 EXPECT_EQ(L->getInductionVariable(SE)->getName(), "i"); 945 }); 946 } 947 948 TEST(LoopInfoTest, LoopNest) { 949 const char *ModuleStr = 950 "define void @foo(i32* %A, i32 %ub) {\n" 951 "entry:\n" 952 " %guardcmp = icmp slt i32 0, %ub\n" 953 " br i1 %guardcmp, label %for.outer.preheader, label %for.end\n" 954 "for.outer.preheader:\n" 955 " br label %for.outer\n" 956 "for.outer:\n" 957 " %j = phi i32 [ 0, %for.outer.preheader ], [ %inc.outer, %for.outer.latch ]\n" 958 " br i1 %guardcmp, label %for.inner.preheader, label %for.outer.latch\n" 959 "for.inner.preheader:\n" 960 " br label %for.inner\n" 961 "for.inner:\n" 962 " %i = phi i32 [ 0, %for.inner.preheader ], [ %inc, %for.inner ]\n" 963 " %idxprom = sext i32 %i to i64\n" 964 " %arrayidx = getelementptr inbounds i32, i32* %A, i64 %idxprom\n" 965 " store i32 %i, i32* %arrayidx, align 4\n" 966 " %inc = add nsw i32 %i, 1\n" 967 " %cmp = icmp slt i32 %inc, %ub\n" 968 " br i1 %cmp, label %for.inner, label %for.inner.exit\n" 969 "for.inner.exit:\n" 970 " br label %for.outer.latch\n" 971 "for.outer.latch:\n" 972 " %inc.outer = add nsw i32 %j, 1\n" 973 " %cmp.outer = icmp slt i32 %inc.outer, %ub\n" 974 " br i1 %cmp.outer, label %for.outer, label %for.outer.exit\n" 975 "for.outer.exit:\n" 976 " br label %for.end\n" 977 "for.end:\n" 978 " ret void\n" 979 "}\n"; 980 981 // Parse the module. 982 LLVMContext Context; 983 std::unique_ptr<Module> M = makeLLVMModule(Context, ModuleStr); 984 985 runWithLoopInfoPlus( 986 *M, "foo", 987 [&](Function &F, LoopInfo &LI, ScalarEvolution &SE, 988 PostDominatorTree &PDT) { 989 Function::iterator FI = F.begin(); 990 // First two basic block are entry and for.outer.preheader - skip them. 991 ++FI; 992 BasicBlock *Header = &*(++FI); 993 assert(Header->getName() == "for.outer"); 994 Loop *L = LI.getLoopFor(Header); 995 EXPECT_NE(L, nullptr); 996 997 Optional<Loop::LoopBounds> Bounds = L->getBounds(SE); 998 EXPECT_NE(Bounds, None); 999 ConstantInt *InitialIVValue = 1000 dyn_cast<ConstantInt>(&Bounds->getInitialIVValue()); 1001 EXPECT_TRUE(InitialIVValue && InitialIVValue->isZero()); 1002 EXPECT_EQ(Bounds->getStepInst().getName(), "inc.outer"); 1003 ConstantInt *StepValue = 1004 dyn_cast_or_null<ConstantInt>(Bounds->getStepValue()); 1005 EXPECT_TRUE(StepValue && StepValue->isOne()); 1006 EXPECT_EQ(Bounds->getFinalIVValue().getName(), "ub"); 1007 EXPECT_EQ(Bounds->getCanonicalPredicate(), ICmpInst::ICMP_SLT); 1008 EXPECT_EQ(Bounds->getDirection(), 1009 Loop::LoopBounds::Direction::Increasing); 1010 EXPECT_EQ(L->getInductionVariable(SE)->getName(), "j"); 1011 1012 // Next two basic blocks are for.outer and for.inner.preheader - skip 1013 // them. 1014 ++FI; 1015 Header = &*(++FI); 1016 assert(Header->getName() == "for.inner"); 1017 L = LI.getLoopFor(Header); 1018 EXPECT_NE(L, nullptr); 1019 1020 Optional<Loop::LoopBounds> InnerBounds = L->getBounds(SE); 1021 EXPECT_NE(InnerBounds, None); 1022 InitialIVValue = 1023 dyn_cast<ConstantInt>(&InnerBounds->getInitialIVValue()); 1024 EXPECT_TRUE(InitialIVValue && InitialIVValue->isZero()); 1025 EXPECT_EQ(InnerBounds->getStepInst().getName(), "inc"); 1026 StepValue = dyn_cast_or_null<ConstantInt>(InnerBounds->getStepValue()); 1027 EXPECT_TRUE(StepValue && StepValue->isOne()); 1028 EXPECT_EQ(InnerBounds->getFinalIVValue().getName(), "ub"); 1029 EXPECT_EQ(InnerBounds->getCanonicalPredicate(), ICmpInst::ICMP_SLT); 1030 EXPECT_EQ(InnerBounds->getDirection(), 1031 Loop::LoopBounds::Direction::Increasing); 1032 EXPECT_EQ(L->getInductionVariable(SE)->getName(), "i"); 1033 }); 1034 } 1035 1036 TEST(LoopInfoTest, AuxiliaryIV) { 1037 const char *ModuleStr = 1038 "define void @foo(i32* %A, i32 %ub) {\n" 1039 "entry:\n" 1040 " %guardcmp = icmp slt i32 0, %ub\n" 1041 " br i1 %guardcmp, label %for.preheader, label %for.end\n" 1042 "for.preheader:\n" 1043 " br label %for.body\n" 1044 "for.body:\n" 1045 " %i = phi i32 [ 0, %for.preheader ], [ %inc, %for.body ]\n" 1046 " %aux = phi i32 [ 0, %for.preheader ], [ %auxinc, %for.body ]\n" 1047 " %loopvariant = phi i32 [ 0, %for.preheader ], [ %loopvariantinc, %for.body ]\n" 1048 " %usedoutside = phi i32 [ 0, %for.preheader ], [ %usedoutsideinc, %for.body ]\n" 1049 " %mulopcode = phi i32 [ 0, %for.preheader ], [ %mulopcodeinc, %for.body ]\n" 1050 " %idxprom = sext i32 %i to i64\n" 1051 " %arrayidx = getelementptr inbounds i32, i32* %A, i64 %idxprom\n" 1052 " store i32 %i, i32* %arrayidx, align 4\n" 1053 " %mulopcodeinc = mul nsw i32 %mulopcode, 5\n" 1054 " %usedoutsideinc = add nsw i32 %usedoutside, 5\n" 1055 " %loopvariantinc = add nsw i32 %loopvariant, %i\n" 1056 " %auxinc = add nsw i32 %aux, 5\n" 1057 " %inc = add nsw i32 %i, 1\n" 1058 " %cmp = icmp slt i32 %inc, %ub\n" 1059 " br i1 %cmp, label %for.body, label %for.exit\n" 1060 "for.exit:\n" 1061 " %lcssa = phi i32 [ %usedoutside, %for.body ]\n" 1062 " br label %for.end\n" 1063 "for.end:\n" 1064 " ret void\n" 1065 "}\n"; 1066 1067 // Parse the module. 1068 LLVMContext Context; 1069 std::unique_ptr<Module> M = makeLLVMModule(Context, ModuleStr); 1070 1071 runWithLoopInfoPlus( 1072 *M, "foo", 1073 [&](Function &F, LoopInfo &LI, ScalarEvolution &SE, 1074 PostDominatorTree &PDT) { 1075 Function::iterator FI = F.begin(); 1076 // First two basic block are entry and for.preheader - skip them. 1077 ++FI; 1078 BasicBlock *Header = &*(++FI); 1079 assert(Header->getName() == "for.body"); 1080 Loop *L = LI.getLoopFor(Header); 1081 EXPECT_NE(L, nullptr); 1082 1083 Optional<Loop::LoopBounds> Bounds = L->getBounds(SE); 1084 EXPECT_NE(Bounds, None); 1085 ConstantInt *InitialIVValue = 1086 dyn_cast<ConstantInt>(&Bounds->getInitialIVValue()); 1087 EXPECT_TRUE(InitialIVValue && InitialIVValue->isZero()); 1088 EXPECT_EQ(Bounds->getStepInst().getName(), "inc"); 1089 ConstantInt *StepValue = 1090 dyn_cast_or_null<ConstantInt>(Bounds->getStepValue()); 1091 EXPECT_TRUE(StepValue && StepValue->isOne()); 1092 EXPECT_EQ(Bounds->getFinalIVValue().getName(), "ub"); 1093 EXPECT_EQ(Bounds->getCanonicalPredicate(), ICmpInst::ICMP_SLT); 1094 EXPECT_EQ(Bounds->getDirection(), 1095 Loop::LoopBounds::Direction::Increasing); 1096 EXPECT_EQ(L->getInductionVariable(SE)->getName(), "i"); 1097 BasicBlock::iterator II = Header->begin(); 1098 PHINode &Instruction_i = cast<PHINode>(*(II)); 1099 EXPECT_TRUE(L->isAuxiliaryInductionVariable(Instruction_i, SE)); 1100 PHINode &Instruction_aux = cast<PHINode>(*(++II)); 1101 EXPECT_TRUE(L->isAuxiliaryInductionVariable(Instruction_aux, SE)); 1102 PHINode &Instruction_loopvariant = cast<PHINode>(*(++II)); 1103 EXPECT_FALSE( 1104 L->isAuxiliaryInductionVariable(Instruction_loopvariant, SE)); 1105 PHINode &Instruction_usedoutside = cast<PHINode>(*(++II)); 1106 EXPECT_FALSE( 1107 L->isAuxiliaryInductionVariable(Instruction_usedoutside, SE)); 1108 PHINode &Instruction_mulopcode = cast<PHINode>(*(++II)); 1109 EXPECT_FALSE( 1110 L->isAuxiliaryInductionVariable(Instruction_mulopcode, SE)); 1111 }); 1112 } 1113 1114 // Examine getUniqueExitBlocks/getUniqueNonLatchExitBlocks functions. 1115 TEST(LoopInfoTest, LoopUniqueExitBlocks) { 1116 const char *ModuleStr = 1117 "target datalayout = \"e-m:o-i64:64-f80:128-n8:16:32:64-S128\"\n" 1118 "define void @foo(i32 %n, i1 %cond) {\n" 1119 "entry:\n" 1120 " br label %for.cond\n" 1121 "for.cond:\n" 1122 " %i.0 = phi i32 [ 0, %entry ], [ %inc, %for.inc ]\n" 1123 " %cmp = icmp slt i32 %i.0, %n\n" 1124 " br i1 %cond, label %for.inc, label %for.end1\n" 1125 "for.inc:\n" 1126 " %inc = add nsw i32 %i.0, 1\n" 1127 " br i1 %cmp, label %for.cond, label %for.end2, !llvm.loop !0\n" 1128 "for.end1:\n" 1129 " br label %for.end\n" 1130 "for.end2:\n" 1131 " br label %for.end\n" 1132 "for.end:\n" 1133 " ret void\n" 1134 "}\n" 1135 "!0 = distinct !{!0, !1}\n" 1136 "!1 = !{!\"llvm.loop.distribute.enable\", i1 true}\n"; 1137 1138 // Parse the module. 1139 LLVMContext Context; 1140 std::unique_ptr<Module> M = makeLLVMModule(Context, ModuleStr); 1141 1142 runWithLoopInfo(*M, "foo", [&](Function &F, LoopInfo &LI) { 1143 Function::iterator FI = F.begin(); 1144 // First basic block is entry - skip it. 1145 BasicBlock *Header = &*(++FI); 1146 assert(Header->getName() == "for.cond"); 1147 Loop *L = LI.getLoopFor(Header); 1148 1149 SmallVector<BasicBlock *, 2> Exits; 1150 // This loop has 2 unique exits. 1151 L->getUniqueExitBlocks(Exits); 1152 EXPECT_TRUE(Exits.size() == 2); 1153 // And one unique non latch exit. 1154 Exits.clear(); 1155 L->getUniqueNonLatchExitBlocks(Exits); 1156 EXPECT_TRUE(Exits.size() == 1); 1157 }); 1158 } 1159