unittests/Transforms/Scalar/LoopPassManagerTest.cpp

   1 //===- llvm/unittest/Analysis/LoopPassManagerTest.cpp - LPM 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/Transforms/Scalar/LoopPassManager.h"
  10 #include "llvm/Analysis/AliasAnalysis.h"
  11 #include "llvm/Analysis/AssumptionCache.h"
  12 #include "llvm/Analysis/ScalarEvolution.h"
  13 #include "llvm/Analysis/TargetLibraryInfo.h"
  14 #include "llvm/Analysis/TargetTransformInfo.h"
  15 #include "llvm/AsmParser/Parser.h"
  16 #include "llvm/IR/Dominators.h"
  17 #include "llvm/IR/Function.h"
  18 #include "llvm/IR/LLVMContext.h"
  19 #include "llvm/IR/Module.h"
  20 #include "llvm/IR/PassManager.h"
  21 #include "llvm/Support/SourceMgr.h"
  22
  23 #include "gmock/gmock.h"
  24 #include "gtest/gtest.h"
  25
  26 using namespace llvm;
  27
  28 namespace {
  29
  30 using testing::DoDefault;
  31 using testing::Return;
  32 using testing::Expectation;
  33 using testing::Invoke;
  34 using testing::InvokeWithoutArgs;
  35 using testing::_;
  36
  37 template <typename DerivedT, typename IRUnitT,
  38           typename AnalysisManagerT = AnalysisManager<IRUnitT>,
  39           typename... ExtraArgTs>
  40 class MockAnalysisHandleBase {
  41 public:
  42   class Analysis : public AnalysisInfoMixin<Analysis> {
  43     friend AnalysisInfoMixin<Analysis>;
  44     friend MockAnalysisHandleBase;
  45     static AnalysisKey Key;
  46
  47     DerivedT *Handle;
  48
  49     Analysis(DerivedT &Handle) : Handle(&Handle) {
  50       static_assert(std::is_base_of<MockAnalysisHandleBase, DerivedT>::value,
  51                     "Must pass the derived type to this template!");
  52     }
  53
  54   public:
  55     class Result {
  56       friend MockAnalysisHandleBase;
  57
  58       DerivedT *Handle;
  59
  60       Result(DerivedT &Handle) : Handle(&Handle) {}
  61
  62     public:
  63       // Forward invalidation events to the mock handle.
  64       bool invalidate(IRUnitT &IR, const PreservedAnalyses &PA,
  65                       typename AnalysisManagerT::Invalidator &Inv) {
  66         return Handle->invalidate(IR, PA, Inv);
  67       }
  68     };
  69
  70     Result run(IRUnitT &IR, AnalysisManagerT &AM, ExtraArgTs... ExtraArgs) {
  71       return Handle->run(IR, AM, ExtraArgs...);
  72     }
  73   };
  74
  75   Analysis getAnalysis() { return Analysis(static_cast<DerivedT &>(*this)); }
  76   typename Analysis::Result getResult() {
  77     return typename Analysis::Result(static_cast<DerivedT &>(*this));
  78   }
  79
  80 protected:
  81   // FIXME: MSVC seems unable to handle a lambda argument to Invoke from within
  82   // the template, so we use a boring static function.
  83   static bool invalidateCallback(IRUnitT &IR, const PreservedAnalyses &PA,
  84                                  typename AnalysisManagerT::Invalidator &Inv) {
  85     auto PAC = PA.template getChecker<Analysis>();
  86     return !PAC.preserved() &&
  87            !PAC.template preservedSet<AllAnalysesOn<IRUnitT>>();
  88   }
  89
  90   /// Derived classes should call this in their constructor to set up default
  91   /// mock actions. (We can't do this in our constructor because this has to
  92   /// run after the DerivedT is constructed.)
  93   void setDefaults() {
  94     ON_CALL(static_cast<DerivedT &>(*this),
  95             run(_, _, testing::Matcher<ExtraArgTs>(_)...))
  96         .WillByDefault(Return(this->getResult()));
  97     ON_CALL(static_cast<DerivedT &>(*this), invalidate(_, _, _))
  98         .WillByDefault(Invoke(&invalidateCallback));
  99   }
 100 };
 101
 102 template <typename DerivedT, typename IRUnitT, typename AnalysisManagerT,
 103           typename... ExtraArgTs>
 104 AnalysisKey MockAnalysisHandleBase<DerivedT, IRUnitT, AnalysisManagerT,
 105                                    ExtraArgTs...>::Analysis::Key;
 106
 107 /// Mock handle for loop analyses.
 108 ///
 109 /// This is provided as a template accepting an (optional) integer. Because
 110 /// analyses are identified and queried by type, this allows constructing
 111 /// multiple handles with distinctly typed nested 'Analysis' types that can be
 112 /// registered and queried. If you want to register multiple loop analysis
 113 /// passes, you'll need to instantiate this type with different values for I.
 114 /// For example:
 115 ///
 116 ///   MockLoopAnalysisHandleTemplate<0> h0;
 117 ///   MockLoopAnalysisHandleTemplate<1> h1;
 118 ///   typedef decltype(h0)::Analysis Analysis0;
 119 ///   typedef decltype(h1)::Analysis Analysis1;
 120 template <size_t I = static_cast<size_t>(-1)>
 121 struct MockLoopAnalysisHandleTemplate
 122     : MockAnalysisHandleBase<MockLoopAnalysisHandleTemplate<I>, Loop,
 123                              LoopAnalysisManager,
 124                              LoopStandardAnalysisResults &> {
 125   typedef typename MockLoopAnalysisHandleTemplate::Analysis Analysis;
 126
 127   MOCK_METHOD3_T(run, typename Analysis::Result(Loop &, LoopAnalysisManager &,
 128                                                 LoopStandardAnalysisResults &));
 129
 130   MOCK_METHOD3_T(invalidate, bool(Loop &, const PreservedAnalyses &,
 131                                   LoopAnalysisManager::Invalidator &));
 132
 133   MockLoopAnalysisHandleTemplate() { this->setDefaults(); }
 134 };
 135
 136 typedef MockLoopAnalysisHandleTemplate<> MockLoopAnalysisHandle;
 137
 138 struct MockFunctionAnalysisHandle
 139     : MockAnalysisHandleBase<MockFunctionAnalysisHandle, Function> {
 140   MOCK_METHOD2(run, Analysis::Result(Function &, FunctionAnalysisManager &));
 141
 142   MOCK_METHOD3(invalidate, bool(Function &, const PreservedAnalyses &,
 143                                 FunctionAnalysisManager::Invalidator &));
 144
 145   MockFunctionAnalysisHandle() { setDefaults(); }
 146 };
 147
 148 template <typename DerivedT, typename IRUnitT,
 149           typename AnalysisManagerT = AnalysisManager<IRUnitT>,
 150           typename... ExtraArgTs>
 151 class MockPassHandleBase {
 152 public:
 153   class Pass : public PassInfoMixin<Pass> {
 154     friend MockPassHandleBase;
 155
 156     DerivedT *Handle;
 157
 158     Pass(DerivedT &Handle) : Handle(&Handle) {
 159       static_assert(std::is_base_of<MockPassHandleBase, DerivedT>::value,
 160                     "Must pass the derived type to this template!");
 161     }
 162
 163   public:
 164     PreservedAnalyses run(IRUnitT &IR, AnalysisManagerT &AM,
 165                           ExtraArgTs... ExtraArgs) {
 166       return Handle->run(IR, AM, ExtraArgs...);
 167     }
 168   };
 169
 170   Pass getPass() { return Pass(static_cast<DerivedT &>(*this)); }
 171
 172 protected:
 173   /// Derived classes should call this in their constructor to set up default
 174   /// mock actions. (We can't do this in our constructor because this has to
 175   /// run after the DerivedT is constructed.)
 176   void setDefaults() {
 177     ON_CALL(static_cast<DerivedT &>(*this),
 178             run(_, _, testing::Matcher<ExtraArgTs>(_)...))
 179         .WillByDefault(Return(PreservedAnalyses::all()));
 180   }
 181 };
 182
 183 struct MockLoopPassHandle
 184     : MockPassHandleBase<MockLoopPassHandle, Loop, LoopAnalysisManager,
 185                          LoopStandardAnalysisResults &, LPMUpdater &> {
 186   MOCK_METHOD4(run,
 187                PreservedAnalyses(Loop &, LoopAnalysisManager &,
 188                                  LoopStandardAnalysisResults &, LPMUpdater &));
 189   MockLoopPassHandle() { setDefaults(); }
 190 };
 191
 192 struct MockFunctionPassHandle
 193     : MockPassHandleBase<MockFunctionPassHandle, Function> {
 194   MOCK_METHOD2(run, PreservedAnalyses(Function &, FunctionAnalysisManager &));
 195
 196   MockFunctionPassHandle() { setDefaults(); }
 197 };
 198
 199 struct MockModulePassHandle : MockPassHandleBase<MockModulePassHandle, Module> {
 200   MOCK_METHOD2(run, PreservedAnalyses(Module &, ModuleAnalysisManager &));
 201
 202   MockModulePassHandle() { setDefaults(); }
 203 };
 204
 205 /// Define a custom matcher for objects which support a 'getName' method
 206 /// returning a StringRef.
 207 ///
 208 /// LLVM often has IR objects or analysis objects which expose a StringRef name
 209 /// and in tests it is convenient to match these by name for readability. This
 210 /// matcher supports any type exposing a getName() method of this form.
 211 ///
 212 /// It should be used as:
 213 ///
 214 ///   HasName("my_function")
 215 ///
 216 /// No namespace or other qualification is required.
 217 MATCHER_P(HasName, Name, "") {
 218   // The matcher's name and argument are printed in the case of failure, but we
 219   // also want to print out the name of the argument. This uses an implicitly
 220   // avaiable std::ostream, so we have to construct a std::string.
 221   *result_listener << "has name '" << arg.getName().str() << "'";
 222   return Name == arg.getName();
 223 }
 224
 225 std::unique_ptr<Module> parseIR(LLVMContext &C, const char *IR) {
 226   SMDiagnostic Err;
 227   return parseAssemblyString(IR, Err, C);
 228 }
 229
 230 class LoopPassManagerTest : public ::testing::Test {
 231 protected:
 232   LLVMContext Context;
 233   std::unique_ptr<Module> M;
 234
 235   LoopAnalysisManager LAM;
 236   FunctionAnalysisManager FAM;
 237   ModuleAnalysisManager MAM;
 238
 239   MockLoopAnalysisHandle MLAHandle;
 240   MockLoopPassHandle MLPHandle;
 241   MockFunctionPassHandle MFPHandle;
 242   MockModulePassHandle MMPHandle;
 243
 244   static PreservedAnalyses
 245   getLoopAnalysisResult(Loop &L, LoopAnalysisManager &AM,
 246                         LoopStandardAnalysisResults &AR, LPMUpdater &) {
 247     (void)AM.getResult<MockLoopAnalysisHandle::Analysis>(L, AR);
 248     return PreservedAnalyses::all();
 249   };
 250
 251 public:
 252   LoopPassManagerTest()
 253       : M(parseIR(Context,
 254                   "define void @f(i1* %ptr) {\n"
 255                   "entry:\n"
 256                   "  br label %loop.0\n"
 257                   "loop.0:\n"
 258                   "  %cond.0 = load volatile i1, i1* %ptr\n"
 259                   "  br i1 %cond.0, label %loop.0.0.ph, label %end\n"
 260                   "loop.0.0.ph:\n"
 261                   "  br label %loop.0.0\n"
 262                   "loop.0.0:\n"
 263                   "  %cond.0.0 = load volatile i1, i1* %ptr\n"
 264                   "  br i1 %cond.0.0, label %loop.0.0, label %loop.0.1.ph\n"
 265                   "loop.0.1.ph:\n"
 266                   "  br label %loop.0.1\n"
 267                   "loop.0.1:\n"
 268                   "  %cond.0.1 = load volatile i1, i1* %ptr\n"
 269                   "  br i1 %cond.0.1, label %loop.0.1, label %loop.0.latch\n"
 270                   "loop.0.latch:\n"
 271                   "  br label %loop.0\n"
 272                   "end:\n"
 273                   "  ret void\n"
 274                   "}\n"
 275                   "\n"
 276                   "define void @g(i1* %ptr) {\n"
 277                   "entry:\n"
 278                   "  br label %loop.g.0\n"
 279                   "loop.g.0:\n"
 280                   "  %cond.0 = load volatile i1, i1* %ptr\n"
 281                   "  br i1 %cond.0, label %loop.g.0, label %end\n"
 282                   "end:\n"
 283                   "  ret void\n"
 284                   "}\n")),
 285         LAM(true), FAM(true), MAM(true) {
 286     // Register our mock analysis.
 287     LAM.registerPass([&] { return MLAHandle.getAnalysis(); });
 288
 289     // We need DominatorTreeAnalysis for LoopAnalysis.
 290     FAM.registerPass([&] { return DominatorTreeAnalysis(); });
 291     FAM.registerPass([&] { return LoopAnalysis(); });
 292     // We also allow loop passes to assume a set of other analyses and so need
 293     // those.
 294     FAM.registerPass([&] { return AAManager(); });
 295     FAM.registerPass([&] { return AssumptionAnalysis(); });
 296     if (EnableMSSALoopDependency)
 297       FAM.registerPass([&] { return MemorySSAAnalysis(); });
 298     FAM.registerPass([&] { return ScalarEvolutionAnalysis(); });
 299     FAM.registerPass([&] { return TargetLibraryAnalysis(); });
 300     FAM.registerPass([&] { return TargetIRAnalysis(); });
 301
 302     // Register required pass instrumentation analysis.
 303     LAM.registerPass([&] { return PassInstrumentationAnalysis(); });
 304     FAM.registerPass([&] { return PassInstrumentationAnalysis(); });
 305     MAM.registerPass([&] { return PassInstrumentationAnalysis(); });
 306
 307     // Cross-register proxies.
 308     LAM.registerPass([&] { return FunctionAnalysisManagerLoopProxy(FAM); });
 309     FAM.registerPass([&] { return LoopAnalysisManagerFunctionProxy(LAM); });
 310     FAM.registerPass([&] { return ModuleAnalysisManagerFunctionProxy(MAM); });
 311     MAM.registerPass([&] { return FunctionAnalysisManagerModuleProxy(FAM); });
 312   }
 313 };
 314
 315 TEST_F(LoopPassManagerTest, Basic) {
 316   ModulePassManager MPM(true);
 317   ::testing::InSequence MakeExpectationsSequenced;
 318
 319   // First we just visit all the loops in all the functions and get their
 320   // analysis results. This will run the analysis a total of four times,
 321   // once for each loop.
 322   EXPECT_CALL(MLPHandle, run(HasName("loop.0.0"), _, _, _))
 323       .WillOnce(Invoke(getLoopAnalysisResult));
 324   EXPECT_CALL(MLAHandle, run(HasName("loop.0.0"), _, _));
 325   EXPECT_CALL(MLPHandle, run(HasName("loop.0.1"), _, _, _))
 326       .WillOnce(Invoke(getLoopAnalysisResult));
 327   EXPECT_CALL(MLAHandle, run(HasName("loop.0.1"), _, _));
 328   EXPECT_CALL(MLPHandle, run(HasName("loop.0"), _, _, _))
 329       .WillOnce(Invoke(getLoopAnalysisResult));
 330   EXPECT_CALL(MLAHandle, run(HasName("loop.0"), _, _));
 331   EXPECT_CALL(MLPHandle, run(HasName("loop.g.0"), _, _, _))
 332       .WillOnce(Invoke(getLoopAnalysisResult));
 333   EXPECT_CALL(MLAHandle, run(HasName("loop.g.0"), _, _));
 334   // Wire the loop pass through pass managers into the module pipeline.
 335   {
 336     LoopPassManager LPM(true);
 337     LPM.addPass(MLPHandle.getPass());
 338     FunctionPassManager FPM(true);
 339     FPM.addPass(createFunctionToLoopPassAdaptor(std::move(LPM)));
 340     MPM.addPass(createModuleToFunctionPassAdaptor(std::move(FPM)));
 341   }
 342
 343   // Next we run two passes over the loops. The first one invalidates the
 344   // analyses for one loop, the second ones try to get the analysis results.
 345   // This should force only one analysis to re-run within the loop PM, but will
 346   // also invalidate everything after the loop pass manager finishes.
 347   EXPECT_CALL(MLPHandle, run(HasName("loop.0.0"), _, _, _))
 348       .WillOnce(DoDefault())
 349       .WillOnce(Invoke(getLoopAnalysisResult));
 350   EXPECT_CALL(MLPHandle, run(HasName("loop.0.1"), _, _, _))
 351       .WillOnce(InvokeWithoutArgs([] { return PreservedAnalyses::none(); }))
 352       .WillOnce(Invoke(getLoopAnalysisResult));
 353   EXPECT_CALL(MLAHandle, run(HasName("loop.0.1"), _, _));
 354   EXPECT_CALL(MLPHandle, run(HasName("loop.0"), _, _, _))
 355       .WillOnce(DoDefault())
 356       .WillOnce(Invoke(getLoopAnalysisResult));
 357   EXPECT_CALL(MLPHandle, run(HasName("loop.g.0"), _, _, _))
 358       .WillOnce(DoDefault())
 359       .WillOnce(Invoke(getLoopAnalysisResult));
 360   // Wire two loop pass runs into the module pipeline.
 361   {
 362     LoopPassManager LPM(true);
 363     LPM.addPass(MLPHandle.getPass());
 364     LPM.addPass(MLPHandle.getPass());
 365     FunctionPassManager FPM(true);
 366     FPM.addPass(createFunctionToLoopPassAdaptor(std::move(LPM)));
 367     MPM.addPass(createModuleToFunctionPassAdaptor(std::move(FPM)));
 368   }
 369
 370   // And now run the pipeline across the module.
 371   MPM.run(*M, MAM);
 372 }
 373
 374 TEST_F(LoopPassManagerTest, FunctionPassInvalidationOfLoopAnalyses) {
 375   ModulePassManager MPM(true);
 376   FunctionPassManager FPM(true);
 377   // We process each function completely in sequence.
 378   ::testing::Sequence FSequence, GSequence;
 379
 380   // First, force the analysis result to be computed for each loop.
 381   EXPECT_CALL(MLAHandle, run(HasName("loop.0.0"), _, _))
 382       .InSequence(FSequence)
 383       .WillOnce(DoDefault());
 384   EXPECT_CALL(MLAHandle, run(HasName("loop.0.1"), _, _))
 385       .InSequence(FSequence)
 386       .WillOnce(DoDefault());
 387   EXPECT_CALL(MLAHandle, run(HasName("loop.0"), _, _))
 388       .InSequence(FSequence)
 389       .WillOnce(DoDefault());
 390   EXPECT_CALL(MLAHandle, run(HasName("loop.g.0"), _, _))
 391       .InSequence(GSequence)
 392       .WillOnce(DoDefault());
 393   FPM.addPass(createFunctionToLoopPassAdaptor(
 394       RequireAnalysisLoopPass<MockLoopAnalysisHandle::Analysis>()));
 395
 396   // No need to re-run if we require again from a fresh loop pass manager.
 397   FPM.addPass(createFunctionToLoopPassAdaptor(
 398       RequireAnalysisLoopPass<MockLoopAnalysisHandle::Analysis>()));
 399   // For 'f', preserve most things but not the specific loop analyses.
 400   auto PA = getLoopPassPreservedAnalyses();
 401   if (EnableMSSALoopDependency)
 402     PA.preserve<MemorySSAAnalysis>();
 403   EXPECT_CALL(MFPHandle, run(HasName("f"), _))
 404       .InSequence(FSequence)
 405       .WillOnce(Return(PA));
 406   EXPECT_CALL(MLAHandle, invalidate(HasName("loop.0.0"), _, _))
 407       .InSequence(FSequence)
 408       .WillOnce(DoDefault());
 409   // On one loop, skip the invalidation (as though we did an internal update).
 410   EXPECT_CALL(MLAHandle, invalidate(HasName("loop.0.1"), _, _))
 411       .InSequence(FSequence)
 412       .WillOnce(Return(false));
 413   EXPECT_CALL(MLAHandle, invalidate(HasName("loop.0"), _, _))
 414       .InSequence(FSequence)
 415       .WillOnce(DoDefault());
 416   // Now two loops still have to be recomputed.
 417   EXPECT_CALL(MLAHandle, run(HasName("loop.0.0"), _, _))
 418       .InSequence(FSequence)
 419       .WillOnce(DoDefault());
 420   EXPECT_CALL(MLAHandle, run(HasName("loop.0"), _, _))
 421       .InSequence(FSequence)
 422       .WillOnce(DoDefault());
 423   // Preserve things in the second function to ensure invalidation remains
 424   // isolated to one function.
 425   EXPECT_CALL(MFPHandle, run(HasName("g"), _))
 426       .InSequence(GSequence)
 427       .WillOnce(DoDefault());
 428   FPM.addPass(MFPHandle.getPass());
 429   FPM.addPass(createFunctionToLoopPassAdaptor(
 430       RequireAnalysisLoopPass<MockLoopAnalysisHandle::Analysis>()));
 431
 432   EXPECT_CALL(MFPHandle, run(HasName("f"), _))
 433       .InSequence(FSequence)
 434       .WillOnce(DoDefault());
 435   // For 'g', fail to preserve anything, causing the loops themselves to be
 436   // cleared. We don't get an invalidation event here as the loop is gone, but
 437   // we should still have to recompute the analysis.
 438   EXPECT_CALL(MFPHandle, run(HasName("g"), _))
 439       .InSequence(GSequence)
 440       .WillOnce(Return(PreservedAnalyses::none()));
 441   EXPECT_CALL(MLAHandle, run(HasName("loop.g.0"), _, _))
 442       .InSequence(GSequence)
 443       .WillOnce(DoDefault());
 444   FPM.addPass(MFPHandle.getPass());
 445   FPM.addPass(createFunctionToLoopPassAdaptor(
 446       RequireAnalysisLoopPass<MockLoopAnalysisHandle::Analysis>()));
 447
 448   MPM.addPass(createModuleToFunctionPassAdaptor(std::move(FPM)));
 449
 450   // Verify with a separate function pass run that we didn't mess up 'f's
 451   // cache. No analysis runs should be necessary here.
 452   MPM.addPass(createModuleToFunctionPassAdaptor(createFunctionToLoopPassAdaptor(
 453       RequireAnalysisLoopPass<MockLoopAnalysisHandle::Analysis>())));
 454
 455   MPM.run(*M, MAM);
 456 }
 457
 458 TEST_F(LoopPassManagerTest, ModulePassInvalidationOfLoopAnalyses) {
 459   ModulePassManager MPM(true);
 460   ::testing::InSequence MakeExpectationsSequenced;
 461
 462   // First, force the analysis result to be computed for each loop.
 463   EXPECT_CALL(MLAHandle, run(HasName("loop.0.0"), _, _));
 464   EXPECT_CALL(MLAHandle, run(HasName("loop.0.1"), _, _));
 465   EXPECT_CALL(MLAHandle, run(HasName("loop.0"), _, _));
 466   EXPECT_CALL(MLAHandle, run(HasName("loop.g.0"), _, _));
 467   MPM.addPass(createModuleToFunctionPassAdaptor(createFunctionToLoopPassAdaptor(
 468       RequireAnalysisLoopPass<MockLoopAnalysisHandle::Analysis>())));
 469
 470   // Walking all the way out and all the way back in doesn't re-run the
 471   // analysis.
 472   MPM.addPass(createModuleToFunctionPassAdaptor(createFunctionToLoopPassAdaptor(
 473       RequireAnalysisLoopPass<MockLoopAnalysisHandle::Analysis>())));
 474
 475   // But a module pass that doesn't preserve the actual mock loop analysis
 476   // invalidates all the way down and forces recomputing.
 477   EXPECT_CALL(MMPHandle, run(_, _)).WillOnce(InvokeWithoutArgs([] {
 478     auto PA = getLoopPassPreservedAnalyses();
 479     PA.preserve<FunctionAnalysisManagerModuleProxy>();
 480     if (EnableMSSALoopDependency)
 481       PA.preserve<MemorySSAAnalysis>();
 482     return PA;
 483   }));
 484   // All the loop analyses from both functions get invalidated before we
 485   // recompute anything.
 486   EXPECT_CALL(MLAHandle, invalidate(HasName("loop.0.0"), _, _));
 487   // On one loop, again skip the invalidation (as though we did an internal
 488   // update).
 489   EXPECT_CALL(MLAHandle, invalidate(HasName("loop.0.1"), _, _))
 490       .WillOnce(Return(false));
 491   EXPECT_CALL(MLAHandle, invalidate(HasName("loop.0"), _, _));
 492   EXPECT_CALL(MLAHandle, invalidate(HasName("loop.g.0"), _, _));
 493   // Now all but one of the loops gets re-analyzed.
 494   EXPECT_CALL(MLAHandle, run(HasName("loop.0.0"), _, _));
 495   EXPECT_CALL(MLAHandle, run(HasName("loop.0"), _, _));
 496   EXPECT_CALL(MLAHandle, run(HasName("loop.g.0"), _, _));
 497   MPM.addPass(MMPHandle.getPass());
 498   MPM.addPass(createModuleToFunctionPassAdaptor(createFunctionToLoopPassAdaptor(
 499       RequireAnalysisLoopPass<MockLoopAnalysisHandle::Analysis>())));
 500
 501   // Verify that the cached values persist.
 502   MPM.addPass(createModuleToFunctionPassAdaptor(createFunctionToLoopPassAdaptor(
 503       RequireAnalysisLoopPass<MockLoopAnalysisHandle::Analysis>())));
 504
 505   // Now we fail to preserve the loop analysis and observe that the loop
 506   // analyses are cleared (so no invalidation event) as the loops themselves
 507   // are no longer valid.
 508   EXPECT_CALL(MMPHandle, run(_, _)).WillOnce(InvokeWithoutArgs([] {
 509     auto PA = PreservedAnalyses::none();
 510     PA.preserve<FunctionAnalysisManagerModuleProxy>();
 511     return PA;
 512   }));
 513   EXPECT_CALL(MLAHandle, run(HasName("loop.0.0"), _, _));
 514   EXPECT_CALL(MLAHandle, run(HasName("loop.0.1"), _, _));
 515   EXPECT_CALL(MLAHandle, run(HasName("loop.0"), _, _));
 516   EXPECT_CALL(MLAHandle, run(HasName("loop.g.0"), _, _));
 517   MPM.addPass(MMPHandle.getPass());
 518   MPM.addPass(createModuleToFunctionPassAdaptor(createFunctionToLoopPassAdaptor(
 519       RequireAnalysisLoopPass<MockLoopAnalysisHandle::Analysis>())));
 520
 521   // Verify that the cached values persist.
 522   MPM.addPass(createModuleToFunctionPassAdaptor(createFunctionToLoopPassAdaptor(
 523       RequireAnalysisLoopPass<MockLoopAnalysisHandle::Analysis>())));
 524
 525   // Next, check that even if we preserve everything within the function itelf,
 526   // if the function's module pass proxy isn't preserved and the potential set
 527   // of functions changes, the clear reaches the loop analyses as well. This
 528   // will again trigger re-runs but not invalidation events.
 529   EXPECT_CALL(MMPHandle, run(_, _)).WillOnce(InvokeWithoutArgs([] {
 530     auto PA = PreservedAnalyses::none();
 531     PA.preserveSet<AllAnalysesOn<Function>>();
 532     PA.preserveSet<AllAnalysesOn<Loop>>();
 533     return PA;
 534   }));
 535   EXPECT_CALL(MLAHandle, run(HasName("loop.0.0"), _, _));
 536   EXPECT_CALL(MLAHandle, run(HasName("loop.0.1"), _, _));
 537   EXPECT_CALL(MLAHandle, run(HasName("loop.0"), _, _));
 538   EXPECT_CALL(MLAHandle, run(HasName("loop.g.0"), _, _));
 539   MPM.addPass(MMPHandle.getPass());
 540   MPM.addPass(createModuleToFunctionPassAdaptor(createFunctionToLoopPassAdaptor(
 541       RequireAnalysisLoopPass<MockLoopAnalysisHandle::Analysis>())));
 542
 543   MPM.run(*M, MAM);
 544 }
 545
 546 // Test that if any of the bundled analyses provided in the LPM's signature
 547 // become invalid, the analysis proxy itself becomes invalid and we clear all
 548 // loop analysis results.
 549 TEST_F(LoopPassManagerTest, InvalidationOfBundledAnalyses) {
 550   ModulePassManager MPM(true);
 551   FunctionPassManager FPM(true);
 552   ::testing::InSequence MakeExpectationsSequenced;
 553
 554   // First, force the analysis result to be computed for each loop.
 555   EXPECT_CALL(MLAHandle, run(HasName("loop.0.0"), _, _));
 556   EXPECT_CALL(MLAHandle, run(HasName("loop.0.1"), _, _));
 557   EXPECT_CALL(MLAHandle, run(HasName("loop.0"), _, _));
 558   FPM.addPass(createFunctionToLoopPassAdaptor(
 559       RequireAnalysisLoopPass<MockLoopAnalysisHandle::Analysis>()));
 560
 561   // No need to re-run if we require again from a fresh loop pass manager.
 562   FPM.addPass(createFunctionToLoopPassAdaptor(
 563       RequireAnalysisLoopPass<MockLoopAnalysisHandle::Analysis>()));
 564
 565   // Preserving everything but the loop analyses themselves results in
 566   // invalidation and running.
 567   EXPECT_CALL(MFPHandle, run(HasName("f"), _))
 568       .WillOnce(Return(getLoopPassPreservedAnalyses()));
 569   EXPECT_CALL(MLAHandle, run(HasName("loop.0.0"), _, _));
 570   EXPECT_CALL(MLAHandle, run(HasName("loop.0.1"), _, _));
 571   EXPECT_CALL(MLAHandle, run(HasName("loop.0"), _, _));
 572   FPM.addPass(MFPHandle.getPass());
 573   FPM.addPass(createFunctionToLoopPassAdaptor(
 574       RequireAnalysisLoopPass<MockLoopAnalysisHandle::Analysis>()));
 575
 576   // The rest don't invalidate analyses, they only trigger re-runs because we
 577   // clear the cache completely.
 578   EXPECT_CALL(MFPHandle, run(HasName("f"), _)).WillOnce(InvokeWithoutArgs([] {
 579     auto PA = PreservedAnalyses::none();
 580     // Not preserving `AAManager`.
 581     PA.preserve<DominatorTreeAnalysis>();
 582     PA.preserve<LoopAnalysis>();
 583     PA.preserve<LoopAnalysisManagerFunctionProxy>();
 584     PA.preserve<ScalarEvolutionAnalysis>();
 585     return PA;
 586   }));
 587   EXPECT_CALL(MLAHandle, run(HasName("loop.0.0"), _, _));
 588   EXPECT_CALL(MLAHandle, run(HasName("loop.0.1"), _, _));
 589   EXPECT_CALL(MLAHandle, run(HasName("loop.0"), _, _));
 590   FPM.addPass(MFPHandle.getPass());
 591   FPM.addPass(createFunctionToLoopPassAdaptor(
 592       RequireAnalysisLoopPass<MockLoopAnalysisHandle::Analysis>()));
 593
 594   EXPECT_CALL(MFPHandle, run(HasName("f"), _)).WillOnce(InvokeWithoutArgs([] {
 595     auto PA = PreservedAnalyses::none();
 596     PA.preserve<AAManager>();
 597     // Not preserving `DominatorTreeAnalysis`.
 598     PA.preserve<LoopAnalysis>();
 599     PA.preserve<LoopAnalysisManagerFunctionProxy>();
 600     PA.preserve<ScalarEvolutionAnalysis>();
 601     return PA;
 602   }));
 603   EXPECT_CALL(MLAHandle, run(HasName("loop.0.0"), _, _));
 604   EXPECT_CALL(MLAHandle, run(HasName("loop.0.1"), _, _));
 605   EXPECT_CALL(MLAHandle, run(HasName("loop.0"), _, _));
 606   FPM.addPass(MFPHandle.getPass());
 607   FPM.addPass(createFunctionToLoopPassAdaptor(
 608       RequireAnalysisLoopPass<MockLoopAnalysisHandle::Analysis>()));
 609
 610   EXPECT_CALL(MFPHandle, run(HasName("f"), _)).WillOnce(InvokeWithoutArgs([] {
 611     auto PA = PreservedAnalyses::none();
 612     PA.preserve<AAManager>();
 613     PA.preserve<DominatorTreeAnalysis>();
 614     // Not preserving the `LoopAnalysis`.
 615     PA.preserve<LoopAnalysisManagerFunctionProxy>();
 616     PA.preserve<ScalarEvolutionAnalysis>();
 617     return PA;
 618   }));
 619   EXPECT_CALL(MLAHandle, run(HasName("loop.0.0"), _, _));
 620   EXPECT_CALL(MLAHandle, run(HasName("loop.0.1"), _, _));
 621   EXPECT_CALL(MLAHandle, run(HasName("loop.0"), _, _));
 622   FPM.addPass(MFPHandle.getPass());
 623   FPM.addPass(createFunctionToLoopPassAdaptor(
 624       RequireAnalysisLoopPass<MockLoopAnalysisHandle::Analysis>()));
 625
 626   EXPECT_CALL(MFPHandle, run(HasName("f"), _)).WillOnce(InvokeWithoutArgs([] {
 627     auto PA = PreservedAnalyses::none();
 628     PA.preserve<AAManager>();
 629     PA.preserve<DominatorTreeAnalysis>();
 630     PA.preserve<LoopAnalysis>();
 631     // Not preserving the `LoopAnalysisManagerFunctionProxy`.
 632     PA.preserve<ScalarEvolutionAnalysis>();
 633     return PA;
 634   }));
 635   EXPECT_CALL(MLAHandle, run(HasName("loop.0.0"), _, _));
 636   EXPECT_CALL(MLAHandle, run(HasName("loop.0.1"), _, _));
 637   EXPECT_CALL(MLAHandle, run(HasName("loop.0"), _, _));
 638   FPM.addPass(MFPHandle.getPass());
 639   FPM.addPass(createFunctionToLoopPassAdaptor(
 640       RequireAnalysisLoopPass<MockLoopAnalysisHandle::Analysis>()));
 641
 642   EXPECT_CALL(MFPHandle, run(HasName("f"), _)).WillOnce(InvokeWithoutArgs([] {
 643     auto PA = PreservedAnalyses::none();
 644     PA.preserve<AAManager>();
 645     PA.preserve<DominatorTreeAnalysis>();
 646     PA.preserve<LoopAnalysis>();
 647     PA.preserve<LoopAnalysisManagerFunctionProxy>();
 648     // Not preserving `ScalarEvolutionAnalysis`.
 649     return PA;
 650   }));
 651   EXPECT_CALL(MLAHandle, run(HasName("loop.0.0"), _, _));
 652   EXPECT_CALL(MLAHandle, run(HasName("loop.0.1"), _, _));
 653   EXPECT_CALL(MLAHandle, run(HasName("loop.0"), _, _));
 654   FPM.addPass(MFPHandle.getPass());
 655   FPM.addPass(createFunctionToLoopPassAdaptor(
 656       RequireAnalysisLoopPass<MockLoopAnalysisHandle::Analysis>()));
 657
 658   // After all the churn on 'f', we'll compute the loop analysis results for
 659   // 'g' once with a requires pass and then run our mock pass over g a bunch
 660   // but just get cached results each time.
 661   EXPECT_CALL(MLAHandle, run(HasName("loop.g.0"), _, _));
 662   EXPECT_CALL(MFPHandle, run(HasName("g"), _)).Times(6);
 663
 664   MPM.addPass(createModuleToFunctionPassAdaptor(std::move(FPM)));
 665   MPM.run(*M, MAM);
 666 }
 667
 668 TEST_F(LoopPassManagerTest, IndirectInvalidation) {
 669   // We need two distinct analysis types and handles.
 670   enum { A, B };
 671   MockLoopAnalysisHandleTemplate<A> MLAHandleA;
 672   MockLoopAnalysisHandleTemplate<B> MLAHandleB;
 673   LAM.registerPass([&] { return MLAHandleA.getAnalysis(); });
 674   LAM.registerPass([&] { return MLAHandleB.getAnalysis(); });
 675   typedef decltype(MLAHandleA)::Analysis AnalysisA;
 676   typedef decltype(MLAHandleB)::Analysis AnalysisB;
 677
 678   // Set up AnalysisA to depend on our AnalysisB. For testing purposes we just
 679   // need to get the AnalysisB results in AnalysisA's run method and check if
 680   // AnalysisB gets invalidated in AnalysisA's invalidate method.
 681   ON_CALL(MLAHandleA, run(_, _, _))
 682       .WillByDefault(Invoke([&](Loop &L, LoopAnalysisManager &AM,
 683                                 LoopStandardAnalysisResults &AR) {
 684         (void)AM.getResult<AnalysisB>(L, AR);
 685         return MLAHandleA.getResult();
 686       }));
 687   ON_CALL(MLAHandleA, invalidate(_, _, _))
 688       .WillByDefault(Invoke([](Loop &L, const PreservedAnalyses &PA,
 689                                LoopAnalysisManager::Invalidator &Inv) {
 690         auto PAC = PA.getChecker<AnalysisA>();
 691         return !(PAC.preserved() || PAC.preservedSet<AllAnalysesOn<Loop>>()) ||
 692                Inv.invalidate<AnalysisB>(L, PA);
 693       }));
 694
 695   ::testing::InSequence MakeExpectationsSequenced;
 696
 697   // Compute the analyses across all of 'f' first.
 698   EXPECT_CALL(MLAHandleA, run(HasName("loop.0.0"), _, _));
 699   EXPECT_CALL(MLAHandleB, run(HasName("loop.0.0"), _, _));
 700   EXPECT_CALL(MLAHandleA, run(HasName("loop.0.1"), _, _));
 701   EXPECT_CALL(MLAHandleB, run(HasName("loop.0.1"), _, _));
 702   EXPECT_CALL(MLAHandleA, run(HasName("loop.0"), _, _));
 703   EXPECT_CALL(MLAHandleB, run(HasName("loop.0"), _, _));
 704
 705   // Now we invalidate AnalysisB (but not AnalysisA) for one of the loops and
 706   // preserve everything for the rest. This in turn triggers that one loop to
 707   // recompute both AnalysisB *and* AnalysisA if indirect invalidation is
 708   // working.
 709   EXPECT_CALL(MLPHandle, run(HasName("loop.0.0"), _, _, _))
 710       .WillOnce(InvokeWithoutArgs([] {
 711         auto PA = getLoopPassPreservedAnalyses();
 712         // Specifically preserve AnalysisA so that it would survive if it
 713         // didn't depend on AnalysisB.
 714         PA.preserve<AnalysisA>();
 715         return PA;
 716       }));
 717   // It happens that AnalysisB is invalidated first. That shouldn't matter
 718   // though, and we should still call AnalysisA's invalidation.
 719   EXPECT_CALL(MLAHandleB, invalidate(HasName("loop.0.0"), _, _));
 720   EXPECT_CALL(MLAHandleA, invalidate(HasName("loop.0.0"), _, _));
 721   EXPECT_CALL(MLPHandle, run(HasName("loop.0.0"), _, _, _))
 722       .WillOnce(Invoke([](Loop &L, LoopAnalysisManager &AM,
 723                           LoopStandardAnalysisResults &AR, LPMUpdater &) {
 724         (void)AM.getResult<AnalysisA>(L, AR);
 725         return PreservedAnalyses::all();
 726       }));
 727   EXPECT_CALL(MLAHandleA, run(HasName("loop.0.0"), _, _));
 728   EXPECT_CALL(MLAHandleB, run(HasName("loop.0.0"), _, _));
 729   // The rest of the loops should run and get cached results.
 730   EXPECT_CALL(MLPHandle, run(HasName("loop.0.1"), _, _, _))
 731       .Times(2)
 732       .WillRepeatedly(Invoke([](Loop &L, LoopAnalysisManager &AM,
 733                                 LoopStandardAnalysisResults &AR, LPMUpdater &) {
 734         (void)AM.getResult<AnalysisA>(L, AR);
 735         return PreservedAnalyses::all();
 736       }));
 737   EXPECT_CALL(MLPHandle, run(HasName("loop.0"), _, _, _))
 738       .Times(2)
 739       .WillRepeatedly(Invoke([](Loop &L, LoopAnalysisManager &AM,
 740                                 LoopStandardAnalysisResults &AR, LPMUpdater &) {
 741         (void)AM.getResult<AnalysisA>(L, AR);
 742         return PreservedAnalyses::all();
 743       }));
 744
 745   // The run over 'g' should be boring, with us just computing the analyses once
 746   // up front and then running loop passes and getting cached results.
 747   EXPECT_CALL(MLAHandleA, run(HasName("loop.g.0"), _, _));
 748   EXPECT_CALL(MLAHandleB, run(HasName("loop.g.0"), _, _));
 749   EXPECT_CALL(MLPHandle, run(HasName("loop.g.0"), _, _, _))
 750       .Times(2)
 751       .WillRepeatedly(Invoke([](Loop &L, LoopAnalysisManager &AM,
 752                                 LoopStandardAnalysisResults &AR, LPMUpdater &) {
 753         (void)AM.getResult<AnalysisA>(L, AR);
 754         return PreservedAnalyses::all();
 755       }));
 756
 757   // Build the pipeline and run it.
 758   ModulePassManager MPM(true);
 759   FunctionPassManager FPM(true);
 760   FPM.addPass(
 761       createFunctionToLoopPassAdaptor(RequireAnalysisLoopPass<AnalysisA>()));
 762   LoopPassManager LPM(true);
 763   LPM.addPass(MLPHandle.getPass());
 764   LPM.addPass(MLPHandle.getPass());
 765   FPM.addPass(createFunctionToLoopPassAdaptor(std::move(LPM)));
 766   MPM.addPass(createModuleToFunctionPassAdaptor(std::move(FPM)));
 767   MPM.run(*M, MAM);
 768 }
 769
 770 TEST_F(LoopPassManagerTest, IndirectOuterPassInvalidation) {
 771   typedef decltype(MLAHandle)::Analysis LoopAnalysis;
 772
 773   MockFunctionAnalysisHandle MFAHandle;
 774   FAM.registerPass([&] { return MFAHandle.getAnalysis(); });
 775   typedef decltype(MFAHandle)::Analysis FunctionAnalysis;
 776
 777   // Set up the loop analysis to depend on both the function and module
 778   // analysis.
 779   ON_CALL(MLAHandle, run(_, _, _))
 780       .WillByDefault(Invoke([&](Loop &L, LoopAnalysisManager &AM,
 781                                 LoopStandardAnalysisResults &AR) {
 782         auto &FAMP = AM.getResult<FunctionAnalysisManagerLoopProxy>(L, AR);
 783         auto &FAM = FAMP.getManager();
 784         Function &F = *L.getHeader()->getParent();
 785         if (FAM.getCachedResult<FunctionAnalysis>(F))
 786           FAMP.registerOuterAnalysisInvalidation<FunctionAnalysis,
 787                                                  LoopAnalysis>();
 788         return MLAHandle.getResult();
 789       }));
 790
 791   ::testing::InSequence MakeExpectationsSequenced;
 792
 793   // Compute the analyses across all of 'f' first.
 794   EXPECT_CALL(MFPHandle, run(HasName("f"), _))
 795       .WillOnce(Invoke([](Function &F, FunctionAnalysisManager &AM) {
 796         // Force the computing of the function analysis so it is available in
 797         // this function.
 798         (void)AM.getResult<FunctionAnalysis>(F);
 799         return PreservedAnalyses::all();
 800       }));
 801   EXPECT_CALL(MLAHandle, run(HasName("loop.0.0"), _, _));
 802   EXPECT_CALL(MLAHandle, run(HasName("loop.0.1"), _, _));
 803   EXPECT_CALL(MLAHandle, run(HasName("loop.0"), _, _));
 804
 805   // Now invalidate the function analysis but preserve the loop analyses.
 806   // This should trigger immediate invalidation of the loop analyses, despite
 807   // the fact that they were preserved.
 808   EXPECT_CALL(MFPHandle, run(HasName("f"), _)).WillOnce(InvokeWithoutArgs([] {
 809     auto PA = getLoopPassPreservedAnalyses();
 810     if (EnableMSSALoopDependency)
 811       PA.preserve<MemorySSAAnalysis>();
 812     PA.preserveSet<AllAnalysesOn<Loop>>();
 813     return PA;
 814   }));
 815   EXPECT_CALL(MLAHandle, invalidate(HasName("loop.0.0"), _, _));
 816   EXPECT_CALL(MLAHandle, invalidate(HasName("loop.0.1"), _, _));
 817   EXPECT_CALL(MLAHandle, invalidate(HasName("loop.0"), _, _));
 818
 819   // And re-running a requires pass recomputes them.
 820   EXPECT_CALL(MLAHandle, run(HasName("loop.0.0"), _, _));
 821   EXPECT_CALL(MLAHandle, run(HasName("loop.0.1"), _, _));
 822   EXPECT_CALL(MLAHandle, run(HasName("loop.0"), _, _));
 823
 824   // When we run over 'g' we don't populate the cache with the function
 825   // analysis.
 826   EXPECT_CALL(MFPHandle, run(HasName("g"), _))
 827       .WillOnce(Return(PreservedAnalyses::all()));
 828   EXPECT_CALL(MLAHandle, run(HasName("loop.g.0"), _, _));
 829
 830   // Which means that no extra invalidation occurs and cached values are used.
 831   EXPECT_CALL(MFPHandle, run(HasName("g"), _)).WillOnce(InvokeWithoutArgs([] {
 832     auto PA = getLoopPassPreservedAnalyses();
 833     if (EnableMSSALoopDependency)
 834       PA.preserve<MemorySSAAnalysis>();
 835     PA.preserveSet<AllAnalysesOn<Loop>>();
 836     return PA;
 837   }));
 838
 839   // Build the pipeline and run it.
 840   ModulePassManager MPM(true);
 841   FunctionPassManager FPM(true);
 842   FPM.addPass(MFPHandle.getPass());
 843   FPM.addPass(
 844       createFunctionToLoopPassAdaptor(RequireAnalysisLoopPass<LoopAnalysis>()));
 845   FPM.addPass(MFPHandle.getPass());
 846   FPM.addPass(
 847       createFunctionToLoopPassAdaptor(RequireAnalysisLoopPass<LoopAnalysis>()));
 848   MPM.addPass(createModuleToFunctionPassAdaptor(std::move(FPM)));
 849   MPM.run(*M, MAM);
 850 }
 851
 852 TEST_F(LoopPassManagerTest, LoopChildInsertion) {
 853   // Super boring module with three loops in a single loop nest.
 854   M = parseIR(Context, "define void @f(i1* %ptr) {\n"
 855                        "entry:\n"
 856                        "  br label %loop.0\n"
 857                        "loop.0:\n"
 858                        "  %cond.0 = load volatile i1, i1* %ptr\n"
 859                        "  br i1 %cond.0, label %loop.0.0.ph, label %end\n"
 860                        "loop.0.0.ph:\n"
 861                        "  br label %loop.0.0\n"
 862                        "loop.0.0:\n"
 863                        "  %cond.0.0 = load volatile i1, i1* %ptr\n"
 864                        "  br i1 %cond.0.0, label %loop.0.0, label %loop.0.1.ph\n"
 865                        "loop.0.1.ph:\n"
 866                        "  br label %loop.0.1\n"
 867                        "loop.0.1:\n"
 868                        "  %cond.0.1 = load volatile i1, i1* %ptr\n"
 869                        "  br i1 %cond.0.1, label %loop.0.1, label %loop.0.2.ph\n"
 870                        "loop.0.2.ph:\n"
 871                        "  br label %loop.0.2\n"
 872                        "loop.0.2:\n"
 873                        "  %cond.0.2 = load volatile i1, i1* %ptr\n"
 874                        "  br i1 %cond.0.2, label %loop.0.2, label %loop.0.latch\n"
 875                        "loop.0.latch:\n"
 876                        "  br label %loop.0\n"
 877                        "end:\n"
 878                        "  ret void\n"
 879                        "}\n");
 880
 881   // Build up variables referring into the IR so we can rewrite it below
 882   // easily.
 883   Function &F = *M->begin();
 884   ASSERT_THAT(F, HasName("f"));
 885   Argument &Ptr = *F.arg_begin();
 886   auto BBI = F.begin();
 887   BasicBlock &EntryBB = *BBI++;
 888   ASSERT_THAT(EntryBB, HasName("entry"));
 889   BasicBlock &Loop0BB = *BBI++;
 890   ASSERT_THAT(Loop0BB, HasName("loop.0"));
 891   BasicBlock &Loop00PHBB = *BBI++;
 892   ASSERT_THAT(Loop00PHBB, HasName("loop.0.0.ph"));
 893   BasicBlock &Loop00BB = *BBI++;
 894   ASSERT_THAT(Loop00BB, HasName("loop.0.0"));
 895   BasicBlock &Loop01PHBB = *BBI++;
 896   ASSERT_THAT(Loop01PHBB, HasName("loop.0.1.ph"));
 897   BasicBlock &Loop01BB = *BBI++;
 898   ASSERT_THAT(Loop01BB, HasName("loop.0.1"));
 899   BasicBlock &Loop02PHBB = *BBI++;
 900   ASSERT_THAT(Loop02PHBB, HasName("loop.0.2.ph"));
 901   BasicBlock &Loop02BB = *BBI++;
 902   ASSERT_THAT(Loop02BB, HasName("loop.0.2"));
 903   BasicBlock &Loop0LatchBB = *BBI++;
 904   ASSERT_THAT(Loop0LatchBB, HasName("loop.0.latch"));
 905   BasicBlock &EndBB = *BBI++;
 906   ASSERT_THAT(EndBB, HasName("end"));
 907   ASSERT_THAT(BBI, F.end());
 908   auto CreateCondBr = [&](BasicBlock *TrueBB, BasicBlock *FalseBB,
 909                           const char *Name, BasicBlock *BB) {
 910     auto *Cond = new LoadInst(Type::getInt1Ty(Context), &Ptr, Name,
 911                               /*isVolatile*/ true, BB);
 912     BranchInst::Create(TrueBB, FalseBB, Cond, BB);
 913   };
 914
 915   // Build the pass managers and register our pipeline. We build a single loop
 916   // pass pipeline consisting of three mock pass runs over each loop. After
 917   // this we run both domtree and loop verification passes to make sure that
 918   // the IR remained valid during our mutations.
 919   ModulePassManager MPM(true);
 920   FunctionPassManager FPM(true);
 921   LoopPassManager LPM(true);
 922   LPM.addPass(MLPHandle.getPass());
 923   LPM.addPass(MLPHandle.getPass());
 924   LPM.addPass(MLPHandle.getPass());
 925   FPM.addPass(createFunctionToLoopPassAdaptor(std::move(LPM)));
 926   FPM.addPass(DominatorTreeVerifierPass());
 927   FPM.addPass(LoopVerifierPass());
 928   MPM.addPass(createModuleToFunctionPassAdaptor(std::move(FPM)));
 929
 930   // All the visit orders are deterministic, so we use simple fully order
 931   // expectations.
 932   ::testing::InSequence MakeExpectationsSequenced;
 933
 934   // We run loop passes three times over each of the loops.
 935   EXPECT_CALL(MLPHandle, run(HasName("loop.0.0"), _, _, _))
 936       .WillOnce(Invoke(getLoopAnalysisResult));
 937   EXPECT_CALL(MLAHandle, run(HasName("loop.0.0"), _, _));
 938   EXPECT_CALL(MLPHandle, run(HasName("loop.0.0"), _, _, _))
 939       .Times(2)
 940       .WillRepeatedly(Invoke(getLoopAnalysisResult));
 941
 942   EXPECT_CALL(MLPHandle, run(HasName("loop.0.1"), _, _, _))
 943       .WillOnce(Invoke(getLoopAnalysisResult));
 944   EXPECT_CALL(MLAHandle, run(HasName("loop.0.1"), _, _));
 945
 946   // When running over the middle loop, the second run inserts two new child
 947   // loops, inserting them and itself into the worklist.
 948   BasicBlock *NewLoop010BB, *NewLoop01LatchBB;
 949   EXPECT_CALL(MLPHandle, run(HasName("loop.0.1"), _, _, _))
 950       .WillOnce(Invoke([&](Loop &L, LoopAnalysisManager &AM,
 951                            LoopStandardAnalysisResults &AR,
 952                            LPMUpdater &Updater) {
 953         auto *NewLoop = AR.LI.AllocateLoop();
 954         L.addChildLoop(NewLoop);
 955         auto *NewLoop010PHBB =
 956             BasicBlock::Create(Context, "loop.0.1.0.ph", &F, &Loop02PHBB);
 957         NewLoop010BB =
 958             BasicBlock::Create(Context, "loop.0.1.0", &F, &Loop02PHBB);
 959         NewLoop01LatchBB =
 960             BasicBlock::Create(Context, "loop.0.1.latch", &F, &Loop02PHBB);
 961         Loop01BB.getTerminator()->replaceUsesOfWith(&Loop01BB, NewLoop010PHBB);
 962         BranchInst::Create(NewLoop010BB, NewLoop010PHBB);
 963         CreateCondBr(NewLoop01LatchBB, NewLoop010BB, "cond.0.1.0",
 964                      NewLoop010BB);
 965         BranchInst::Create(&Loop01BB, NewLoop01LatchBB);
 966         AR.DT.addNewBlock(NewLoop010PHBB, &Loop01BB);
 967         AR.DT.addNewBlock(NewLoop010BB, NewLoop010PHBB);
 968         AR.DT.addNewBlock(NewLoop01LatchBB, NewLoop010BB);
 969         EXPECT_TRUE(AR.DT.verify());
 970         L.addBasicBlockToLoop(NewLoop010PHBB, AR.LI);
 971         NewLoop->addBasicBlockToLoop(NewLoop010BB, AR.LI);
 972         L.addBasicBlockToLoop(NewLoop01LatchBB, AR.LI);
 973         NewLoop->verifyLoop();
 974         L.verifyLoop();
 975         Updater.addChildLoops({NewLoop});
 976         return PreservedAnalyses::all();
 977       }));
 978
 979   // We should immediately drop down to fully visit the new inner loop.
 980   EXPECT_CALL(MLPHandle, run(HasName("loop.0.1.0"), _, _, _))
 981       .WillOnce(Invoke(getLoopAnalysisResult));
 982   EXPECT_CALL(MLAHandle, run(HasName("loop.0.1.0"), _, _));
 983   EXPECT_CALL(MLPHandle, run(HasName("loop.0.1.0"), _, _, _))
 984       .Times(2)
 985       .WillRepeatedly(Invoke(getLoopAnalysisResult));
 986
 987   // After visiting the inner loop, we should re-visit the second loop
 988   // reflecting its new loop nest structure.
 989   EXPECT_CALL(MLPHandle, run(HasName("loop.0.1"), _, _, _))
 990       .WillOnce(Invoke(getLoopAnalysisResult));
 991
 992   // In the second run over the middle loop after we've visited the new child,
 993   // we add another child to check that we can repeatedly add children, and add
 994   // children to a loop that already has children.
 995   EXPECT_CALL(MLPHandle, run(HasName("loop.0.1"), _, _, _))
 996       .WillOnce(Invoke([&](Loop &L, LoopAnalysisManager &AM,
 997                            LoopStandardAnalysisResults &AR,
 998                            LPMUpdater &Updater) {
 999         auto *NewLoop = AR.LI.AllocateLoop();
1000         L.addChildLoop(NewLoop);
1001         auto *NewLoop011PHBB = BasicBlock::Create(Context, "loop.0.1.1.ph", &F, NewLoop01LatchBB);
1002         auto *NewLoop011BB = BasicBlock::Create(Context, "loop.0.1.1", &F, NewLoop01LatchBB);
1003         NewLoop010BB->getTerminator()->replaceUsesOfWith(NewLoop01LatchBB,
1004                                                          NewLoop011PHBB);
1005         BranchInst::Create(NewLoop011BB, NewLoop011PHBB);
1006         CreateCondBr(NewLoop01LatchBB, NewLoop011BB, "cond.0.1.1",
1007                      NewLoop011BB);
1008         AR.DT.addNewBlock(NewLoop011PHBB, NewLoop010BB);
1009         auto *NewDTNode = AR.DT.addNewBlock(NewLoop011BB, NewLoop011PHBB);
1010         AR.DT.changeImmediateDominator(AR.DT[NewLoop01LatchBB], NewDTNode);
1011         EXPECT_TRUE(AR.DT.verify());
1012         L.addBasicBlockToLoop(NewLoop011PHBB, AR.LI);
1013         NewLoop->addBasicBlockToLoop(NewLoop011BB, AR.LI);
1014         NewLoop->verifyLoop();
1015         L.verifyLoop();
1016         Updater.addChildLoops({NewLoop});
1017         return PreservedAnalyses::all();
1018       }));
1019
1020   // Again, we should immediately drop down to visit the new, unvisited child
1021   // loop. We don't need to revisit the other child though.
1022   EXPECT_CALL(MLPHandle, run(HasName("loop.0.1.1"), _, _, _))
1023       .WillOnce(Invoke(getLoopAnalysisResult));
1024   EXPECT_CALL(MLAHandle, run(HasName("loop.0.1.1"), _, _));
1025   EXPECT_CALL(MLPHandle, run(HasName("loop.0.1.1"), _, _, _))
1026       .Times(2)
1027       .WillRepeatedly(Invoke(getLoopAnalysisResult));
1028
1029   // And now we should pop back up to the second loop and do a full pipeline of
1030   // three passes on its current form.
1031   EXPECT_CALL(MLPHandle, run(HasName("loop.0.1"), _, _, _))
1032       .Times(3)
1033       .WillRepeatedly(Invoke(getLoopAnalysisResult));
1034
1035   EXPECT_CALL(MLPHandle, run(HasName("loop.0.2"), _, _, _))
1036       .WillOnce(Invoke(getLoopAnalysisResult));
1037   EXPECT_CALL(MLAHandle, run(HasName("loop.0.2"), _, _));
1038   EXPECT_CALL(MLPHandle, run(HasName("loop.0.2"), _, _, _))
1039       .Times(2)
1040       .WillRepeatedly(Invoke(getLoopAnalysisResult));
1041
1042   EXPECT_CALL(MLPHandle, run(HasName("loop.0"), _, _, _))
1043       .WillOnce(Invoke(getLoopAnalysisResult));
1044   EXPECT_CALL(MLAHandle, run(HasName("loop.0"), _, _));
1045   EXPECT_CALL(MLPHandle, run(HasName("loop.0"), _, _, _))
1046       .Times(2)
1047       .WillRepeatedly(Invoke(getLoopAnalysisResult));
1048
1049   // Now that all the expected actions are registered, run the pipeline over
1050   // our module. All of our expectations are verified when the test finishes.
1051   MPM.run(*M, MAM);
1052 }
1053
1054 TEST_F(LoopPassManagerTest, LoopPeerInsertion) {
1055   // Super boring module with two loop nests and loop nest with two child
1056   // loops.
1057   M = parseIR(Context, "define void @f(i1* %ptr) {\n"
1058                        "entry:\n"
1059                        "  br label %loop.0\n"
1060                        "loop.0:\n"
1061                        "  %cond.0 = load volatile i1, i1* %ptr\n"
1062                        "  br i1 %cond.0, label %loop.0.0.ph, label %loop.2.ph\n"
1063                        "loop.0.0.ph:\n"
1064                        "  br label %loop.0.0\n"
1065                        "loop.0.0:\n"
1066                        "  %cond.0.0 = load volatile i1, i1* %ptr\n"
1067                        "  br i1 %cond.0.0, label %loop.0.0, label %loop.0.2.ph\n"
1068                        "loop.0.2.ph:\n"
1069                        "  br label %loop.0.2\n"
1070                        "loop.0.2:\n"
1071                        "  %cond.0.2 = load volatile i1, i1* %ptr\n"
1072                        "  br i1 %cond.0.2, label %loop.0.2, label %loop.0.latch\n"
1073                        "loop.0.latch:\n"
1074                        "  br label %loop.0\n"
1075                        "loop.2.ph:\n"
1076                        "  br label %loop.2\n"
1077                        "loop.2:\n"
1078                        "  %cond.2 = load volatile i1, i1* %ptr\n"
1079                        "  br i1 %cond.2, label %loop.2, label %end\n"
1080                        "end:\n"
1081                        "  ret void\n"
1082                        "}\n");
1083
1084   // Build up variables referring into the IR so we can rewrite it below
1085   // easily.
1086   Function &F = *M->begin();
1087   ASSERT_THAT(F, HasName("f"));
1088   Argument &Ptr = *F.arg_begin();
1089   auto BBI = F.begin();
1090   BasicBlock &EntryBB = *BBI++;
1091   ASSERT_THAT(EntryBB, HasName("entry"));
1092   BasicBlock &Loop0BB = *BBI++;
1093   ASSERT_THAT(Loop0BB, HasName("loop.0"));
1094   BasicBlock &Loop00PHBB = *BBI++;
1095   ASSERT_THAT(Loop00PHBB, HasName("loop.0.0.ph"));
1096   BasicBlock &Loop00BB = *BBI++;
1097   ASSERT_THAT(Loop00BB, HasName("loop.0.0"));
1098   BasicBlock &Loop02PHBB = *BBI++;
1099   ASSERT_THAT(Loop02PHBB, HasName("loop.0.2.ph"));
1100   BasicBlock &Loop02BB = *BBI++;
1101   ASSERT_THAT(Loop02BB, HasName("loop.0.2"));
1102   BasicBlock &Loop0LatchBB = *BBI++;
1103   ASSERT_THAT(Loop0LatchBB, HasName("loop.0.latch"));
1104   BasicBlock &Loop2PHBB = *BBI++;
1105   ASSERT_THAT(Loop2PHBB, HasName("loop.2.ph"));
1106   BasicBlock &Loop2BB = *BBI++;
1107   ASSERT_THAT(Loop2BB, HasName("loop.2"));
1108   BasicBlock &EndBB = *BBI++;
1109   ASSERT_THAT(EndBB, HasName("end"));
1110   ASSERT_THAT(BBI, F.end());
1111   auto CreateCondBr = [&](BasicBlock *TrueBB, BasicBlock *FalseBB,
1112                           const char *Name, BasicBlock *BB) {
1113     auto *Cond = new LoadInst(Type::getInt1Ty(Context), &Ptr, Name,
1114                               /*isVolatile*/ true, BB);
1115     BranchInst::Create(TrueBB, FalseBB, Cond, BB);
1116   };
1117
1118   // Build the pass managers and register our pipeline. We build a single loop
1119   // pass pipeline consisting of three mock pass runs over each loop. After
1120   // this we run both domtree and loop verification passes to make sure that
1121   // the IR remained valid during our mutations.
1122   ModulePassManager MPM(true);
1123   FunctionPassManager FPM(true);
1124   LoopPassManager LPM(true);
1125   LPM.addPass(MLPHandle.getPass());
1126   LPM.addPass(MLPHandle.getPass());
1127   LPM.addPass(MLPHandle.getPass());
1128   FPM.addPass(createFunctionToLoopPassAdaptor(std::move(LPM)));
1129   FPM.addPass(DominatorTreeVerifierPass());
1130   FPM.addPass(LoopVerifierPass());
1131   MPM.addPass(createModuleToFunctionPassAdaptor(std::move(FPM)));
1132
1133   // All the visit orders are deterministic, so we use simple fully order
1134   // expectations.
1135   ::testing::InSequence MakeExpectationsSequenced;
1136
1137   // We run loop passes three times over each of the loops.
1138   EXPECT_CALL(MLPHandle, run(HasName("loop.0.0"), _, _, _))
1139       .WillOnce(Invoke(getLoopAnalysisResult));
1140   EXPECT_CALL(MLAHandle, run(HasName("loop.0.0"), _, _));
1141
1142   // On the second run, we insert a sibling loop.
1143   EXPECT_CALL(MLPHandle, run(HasName("loop.0.0"), _, _, _))
1144       .WillOnce(Invoke([&](Loop &L, LoopAnalysisManager &AM,
1145                            LoopStandardAnalysisResults &AR,
1146                            LPMUpdater &Updater) {
1147         auto *NewLoop = AR.LI.AllocateLoop();
1148         L.getParentLoop()->addChildLoop(NewLoop);
1149         auto *NewLoop01PHBB = BasicBlock::Create(Context, "loop.0.1.ph", &F, &Loop02PHBB);
1150         auto *NewLoop01BB = BasicBlock::Create(Context, "loop.0.1", &F, &Loop02PHBB);
1151         BranchInst::Create(NewLoop01BB, NewLoop01PHBB);
1152         CreateCondBr(&Loop02PHBB, NewLoop01BB, "cond.0.1", NewLoop01BB);
1153         Loop00BB.getTerminator()->replaceUsesOfWith(&Loop02PHBB, NewLoop01PHBB);
1154         AR.DT.addNewBlock(NewLoop01PHBB, &Loop00BB);
1155         auto *NewDTNode = AR.DT.addNewBlock(NewLoop01BB, NewLoop01PHBB);
1156         AR.DT.changeImmediateDominator(AR.DT[&Loop02PHBB], NewDTNode);
1157         EXPECT_TRUE(AR.DT.verify());
1158         L.getParentLoop()->addBasicBlockToLoop(NewLoop01PHBB, AR.LI);
1159         NewLoop->addBasicBlockToLoop(NewLoop01BB, AR.LI);
1160         L.getParentLoop()->verifyLoop();
1161         Updater.addSiblingLoops({NewLoop});
1162         return PreservedAnalyses::all();
1163       }));
1164   // We finish processing this loop as sibling loops don't perturb the
1165   // postorder walk.
1166   EXPECT_CALL(MLPHandle, run(HasName("loop.0.0"), _, _, _))
1167       .WillOnce(Invoke(getLoopAnalysisResult));
1168
1169   // We visit the inserted sibling next.
1170   EXPECT_CALL(MLPHandle, run(HasName("loop.0.1"), _, _, _))
1171       .WillOnce(Invoke(getLoopAnalysisResult));
1172   EXPECT_CALL(MLAHandle, run(HasName("loop.0.1"), _, _));
1173   EXPECT_CALL(MLPHandle, run(HasName("loop.0.1"), _, _, _))
1174       .Times(2)
1175       .WillRepeatedly(Invoke(getLoopAnalysisResult));
1176
1177   EXPECT_CALL(MLPHandle, run(HasName("loop.0.2"), _, _, _))
1178       .WillOnce(Invoke(getLoopAnalysisResult));
1179   EXPECT_CALL(MLAHandle, run(HasName("loop.0.2"), _, _));
1180   EXPECT_CALL(MLPHandle, run(HasName("loop.0.2"), _, _, _))
1181       .WillOnce(Invoke(getLoopAnalysisResult));
1182   // Next, on the third pass run on the last inner loop we add more new
1183   // siblings, more than one, and one with nested child loops. By doing this at
1184   // the end we make sure that edge case works well.
1185   EXPECT_CALL(MLPHandle, run(HasName("loop.0.2"), _, _, _))
1186       .WillOnce(Invoke([&](Loop &L, LoopAnalysisManager &AM,
1187                            LoopStandardAnalysisResults &AR,
1188                            LPMUpdater &Updater) {
1189         Loop *NewLoops[] = {AR.LI.AllocateLoop(), AR.LI.AllocateLoop(),
1190                             AR.LI.AllocateLoop()};
1191         L.getParentLoop()->addChildLoop(NewLoops[0]);
1192         L.getParentLoop()->addChildLoop(NewLoops[1]);
1193         NewLoops[1]->addChildLoop(NewLoops[2]);
1194         auto *NewLoop03PHBB =
1195             BasicBlock::Create(Context, "loop.0.3.ph", &F, &Loop0LatchBB);
1196         auto *NewLoop03BB =
1197             BasicBlock::Create(Context, "loop.0.3", &F, &Loop0LatchBB);
1198         auto *NewLoop04PHBB =
1199             BasicBlock::Create(Context, "loop.0.4.ph", &F, &Loop0LatchBB);
1200         auto *NewLoop04BB =
1201             BasicBlock::Create(Context, "loop.0.4", &F, &Loop0LatchBB);
1202         auto *NewLoop040PHBB =
1203             BasicBlock::Create(Context, "loop.0.4.0.ph", &F, &Loop0LatchBB);
1204         auto *NewLoop040BB =
1205             BasicBlock::Create(Context, "loop.0.4.0", &F, &Loop0LatchBB);
1206         auto *NewLoop04LatchBB =
1207             BasicBlock::Create(Context, "loop.0.4.latch", &F, &Loop0LatchBB);
1208         Loop02BB.getTerminator()->replaceUsesOfWith(&Loop0LatchBB, NewLoop03PHBB);
1209         BranchInst::Create(NewLoop03BB, NewLoop03PHBB);
1210         CreateCondBr(NewLoop04PHBB, NewLoop03BB, "cond.0.3", NewLoop03BB);
1211         BranchInst::Create(NewLoop04BB, NewLoop04PHBB);
1212         CreateCondBr(&Loop0LatchBB, NewLoop040PHBB, "cond.0.4", NewLoop04BB);
1213         BranchInst::Create(NewLoop040BB, NewLoop040PHBB);
1214         CreateCondBr(NewLoop04LatchBB, NewLoop040BB, "cond.0.4.0", NewLoop040BB);
1215         BranchInst::Create(NewLoop04BB, NewLoop04LatchBB);
1216         AR.DT.addNewBlock(NewLoop03PHBB, &Loop02BB);
1217         AR.DT.addNewBlock(NewLoop03BB, NewLoop03PHBB);
1218         AR.DT.addNewBlock(NewLoop04PHBB, NewLoop03BB);
1219         auto *NewDTNode = AR.DT.addNewBlock(NewLoop04BB, NewLoop04PHBB);
1220         AR.DT.changeImmediateDominator(AR.DT[&Loop0LatchBB], NewDTNode);
1221         AR.DT.addNewBlock(NewLoop040PHBB, NewLoop04BB);
1222         AR.DT.addNewBlock(NewLoop040BB, NewLoop040PHBB);
1223         AR.DT.addNewBlock(NewLoop04LatchBB, NewLoop040BB);
1224         EXPECT_TRUE(AR.DT.verify());
1225         L.getParentLoop()->addBasicBlockToLoop(NewLoop03PHBB, AR.LI);
1226         NewLoops[0]->addBasicBlockToLoop(NewLoop03BB, AR.LI);
1227         L.getParentLoop()->addBasicBlockToLoop(NewLoop04PHBB, AR.LI);
1228         NewLoops[1]->addBasicBlockToLoop(NewLoop04BB, AR.LI);
1229         NewLoops[1]->addBasicBlockToLoop(NewLoop040PHBB, AR.LI);
1230         NewLoops[2]->addBasicBlockToLoop(NewLoop040BB, AR.LI);
1231         NewLoops[1]->addBasicBlockToLoop(NewLoop04LatchBB, AR.LI);
1232         L.getParentLoop()->verifyLoop();
1233         Updater.addSiblingLoops({NewLoops[0], NewLoops[1]});
1234         return PreservedAnalyses::all();
1235       }));
1236
1237   EXPECT_CALL(MLPHandle, run(HasName("loop.0.3"), _, _, _))
1238       .WillOnce(Invoke(getLoopAnalysisResult));
1239   EXPECT_CALL(MLAHandle, run(HasName("loop.0.3"), _, _));
1240   EXPECT_CALL(MLPHandle, run(HasName("loop.0.3"), _, _, _))
1241       .Times(2)
1242       .WillRepeatedly(Invoke(getLoopAnalysisResult));
1243
1244   // Note that we need to visit the inner loop of this added sibling before the
1245   // sibling itself!
1246   EXPECT_CALL(MLPHandle, run(HasName("loop.0.4.0"), _, _, _))
1247       .WillOnce(Invoke(getLoopAnalysisResult));
1248   EXPECT_CALL(MLAHandle, run(HasName("loop.0.4.0"), _, _));
1249   EXPECT_CALL(MLPHandle, run(HasName("loop.0.4.0"), _, _, _))
1250       .Times(2)
1251       .WillRepeatedly(Invoke(getLoopAnalysisResult));
1252
1253   EXPECT_CALL(MLPHandle, run(HasName("loop.0.4"), _, _, _))
1254       .WillOnce(Invoke(getLoopAnalysisResult));
1255   EXPECT_CALL(MLAHandle, run(HasName("loop.0.4"), _, _));
1256   EXPECT_CALL(MLPHandle, run(HasName("loop.0.4"), _, _, _))
1257       .Times(2)
1258       .WillRepeatedly(Invoke(getLoopAnalysisResult));
1259
1260   // And only now do we visit the outermost loop of the nest.
1261   EXPECT_CALL(MLPHandle, run(HasName("loop.0"), _, _, _))
1262       .WillOnce(Invoke(getLoopAnalysisResult));
1263   EXPECT_CALL(MLAHandle, run(HasName("loop.0"), _, _));
1264   // On the second pass, we add sibling loops which become new top-level loops.
1265   EXPECT_CALL(MLPHandle, run(HasName("loop.0"), _, _, _))
1266       .WillOnce(Invoke([&](Loop &L, LoopAnalysisManager &AM,
1267                            LoopStandardAnalysisResults &AR,
1268                            LPMUpdater &Updater) {
1269         auto *NewLoop = AR.LI.AllocateLoop();
1270         AR.LI.addTopLevelLoop(NewLoop);
1271         auto *NewLoop1PHBB = BasicBlock::Create(Context, "loop.1.ph", &F, &Loop2BB);
1272         auto *NewLoop1BB = BasicBlock::Create(Context, "loop.1", &F, &Loop2BB);
1273         BranchInst::Create(NewLoop1BB, NewLoop1PHBB);
1274         CreateCondBr(&Loop2PHBB, NewLoop1BB, "cond.1", NewLoop1BB);
1275         Loop0BB.getTerminator()->replaceUsesOfWith(&Loop2PHBB, NewLoop1PHBB);
1276         AR.DT.addNewBlock(NewLoop1PHBB, &Loop0BB);
1277         auto *NewDTNode = AR.DT.addNewBlock(NewLoop1BB, NewLoop1PHBB);
1278         AR.DT.changeImmediateDominator(AR.DT[&Loop2PHBB], NewDTNode);
1279         EXPECT_TRUE(AR.DT.verify());
1280         NewLoop->addBasicBlockToLoop(NewLoop1BB, AR.LI);
1281         NewLoop->verifyLoop();
1282         Updater.addSiblingLoops({NewLoop});
1283         return PreservedAnalyses::all();
1284       }));
1285   EXPECT_CALL(MLPHandle, run(HasName("loop.0"), _, _, _))
1286       .WillOnce(Invoke(getLoopAnalysisResult));
1287
1288   EXPECT_CALL(MLPHandle, run(HasName("loop.1"), _, _, _))
1289       .WillOnce(Invoke(getLoopAnalysisResult));
1290   EXPECT_CALL(MLAHandle, run(HasName("loop.1"), _, _));
1291   EXPECT_CALL(MLPHandle, run(HasName("loop.1"), _, _, _))
1292       .Times(2)
1293       .WillRepeatedly(Invoke(getLoopAnalysisResult));
1294
1295   EXPECT_CALL(MLPHandle, run(HasName("loop.2"), _, _, _))
1296       .WillOnce(Invoke(getLoopAnalysisResult));
1297   EXPECT_CALL(MLAHandle, run(HasName("loop.2"), _, _));
1298   EXPECT_CALL(MLPHandle, run(HasName("loop.2"), _, _, _))
1299       .Times(2)
1300       .WillRepeatedly(Invoke(getLoopAnalysisResult));
1301
1302   // Now that all the expected actions are registered, run the pipeline over
1303   // our module. All of our expectations are verified when the test finishes.
1304   MPM.run(*M, MAM);
1305 }
1306
1307 TEST_F(LoopPassManagerTest, LoopDeletion) {
1308   // Build a module with a single loop nest that contains one outer loop with
1309   // three subloops, and one of those with its own subloop. We will
1310   // incrementally delete all of these to test different deletion scenarios.
1311   M = parseIR(Context, "define void @f(i1* %ptr) {\n"
1312                        "entry:\n"
1313                        "  br label %loop.0\n"
1314                        "loop.0:\n"
1315                        "  %cond.0 = load volatile i1, i1* %ptr\n"
1316                        "  br i1 %cond.0, label %loop.0.0.ph, label %end\n"
1317                        "loop.0.0.ph:\n"
1318                        "  br label %loop.0.0\n"
1319                        "loop.0.0:\n"
1320                        "  %cond.0.0 = load volatile i1, i1* %ptr\n"
1321                        "  br i1 %cond.0.0, label %loop.0.0, label %loop.0.1.ph\n"
1322                        "loop.0.1.ph:\n"
1323                        "  br label %loop.0.1\n"
1324                        "loop.0.1:\n"
1325                        "  %cond.0.1 = load volatile i1, i1* %ptr\n"
1326                        "  br i1 %cond.0.1, label %loop.0.1, label %loop.0.2.ph\n"
1327                        "loop.0.2.ph:\n"
1328                        "  br label %loop.0.2\n"
1329                        "loop.0.2:\n"
1330                        "  %cond.0.2 = load volatile i1, i1* %ptr\n"
1331                        "  br i1 %cond.0.2, label %loop.0.2.0.ph, label %loop.0.latch\n"
1332                        "loop.0.2.0.ph:\n"
1333                        "  br label %loop.0.2.0\n"
1334                        "loop.0.2.0:\n"
1335                        "  %cond.0.2.0 = load volatile i1, i1* %ptr\n"
1336                        "  br i1 %cond.0.2.0, label %loop.0.2.0, label %loop.0.2.latch\n"
1337                        "loop.0.2.latch:\n"
1338                        "  br label %loop.0.2\n"
1339                        "loop.0.latch:\n"
1340                        "  br label %loop.0\n"
1341                        "end:\n"
1342                        "  ret void\n"
1343                        "}\n");
1344
1345   // Build up variables referring into the IR so we can rewrite it below
1346   // easily.
1347   Function &F = *M->begin();
1348   ASSERT_THAT(F, HasName("f"));
1349   Argument &Ptr = *F.arg_begin();
1350   auto BBI = F.begin();
1351   BasicBlock &EntryBB = *BBI++;
1352   ASSERT_THAT(EntryBB, HasName("entry"));
1353   BasicBlock &Loop0BB = *BBI++;
1354   ASSERT_THAT(Loop0BB, HasName("loop.0"));
1355   BasicBlock &Loop00PHBB = *BBI++;
1356   ASSERT_THAT(Loop00PHBB, HasName("loop.0.0.ph"));
1357   BasicBlock &Loop00BB = *BBI++;
1358   ASSERT_THAT(Loop00BB, HasName("loop.0.0"));
1359   BasicBlock &Loop01PHBB = *BBI++;
1360   ASSERT_THAT(Loop01PHBB, HasName("loop.0.1.ph"));
1361   BasicBlock &Loop01BB = *BBI++;
1362   ASSERT_THAT(Loop01BB, HasName("loop.0.1"));
1363   BasicBlock &Loop02PHBB = *BBI++;
1364   ASSERT_THAT(Loop02PHBB, HasName("loop.0.2.ph"));
1365   BasicBlock &Loop02BB = *BBI++;
1366   ASSERT_THAT(Loop02BB, HasName("loop.0.2"));
1367   BasicBlock &Loop020PHBB = *BBI++;
1368   ASSERT_THAT(Loop020PHBB, HasName("loop.0.2.0.ph"));
1369   BasicBlock &Loop020BB = *BBI++;
1370   ASSERT_THAT(Loop020BB, HasName("loop.0.2.0"));
1371   BasicBlock &Loop02LatchBB = *BBI++;
1372   ASSERT_THAT(Loop02LatchBB, HasName("loop.0.2.latch"));
1373   BasicBlock &Loop0LatchBB = *BBI++;
1374   ASSERT_THAT(Loop0LatchBB, HasName("loop.0.latch"));
1375   BasicBlock &EndBB = *BBI++;
1376   ASSERT_THAT(EndBB, HasName("end"));
1377   ASSERT_THAT(BBI, F.end());
1378
1379   // Helper to do the actual deletion of a loop. We directly encode this here
1380   // to isolate ourselves from the rest of LLVM and for simplicity. Here we can
1381   // egregiously cheat based on knowledge of the test case. For example, we
1382   // have no PHI nodes and there is always a single i-dom.
1383   auto EraseLoop = [](Loop &L, BasicBlock &IDomBB,
1384                       LoopStandardAnalysisResults &AR, LPMUpdater &Updater) {
1385     assert(L.empty() && "Can only delete leaf loops with this routine!");
1386     SmallVector<BasicBlock *, 4> LoopBBs(L.block_begin(), L.block_end());
1387     Updater.markLoopAsDeleted(L, L.getName());
1388     IDomBB.getTerminator()->replaceUsesOfWith(L.getHeader(),
1389                                               L.getUniqueExitBlock());
1390     for (BasicBlock *LoopBB : LoopBBs) {
1391       SmallVector<DomTreeNode *, 4> ChildNodes(AR.DT[LoopBB]->begin(),
1392                                                AR.DT[LoopBB]->end());
1393       for (DomTreeNode *ChildNode : ChildNodes)
1394         AR.DT.changeImmediateDominator(ChildNode, AR.DT[&IDomBB]);
1395       AR.DT.eraseNode(LoopBB);
1396       AR.LI.removeBlock(LoopBB);
1397       LoopBB->dropAllReferences();
1398     }
1399     for (BasicBlock *LoopBB : LoopBBs)
1400       LoopBB->eraseFromParent();
1401
1402     AR.LI.erase(&L);
1403   };
1404
1405   // Build up the pass managers.
1406   ModulePassManager MPM(true);
1407   FunctionPassManager FPM(true);
1408   // We run several loop pass pipelines across the loop nest, but they all take
1409   // the same form of three mock pass runs in a loop pipeline followed by
1410   // domtree and loop verification. We use a lambda to stamp this out each
1411   // time.
1412   auto AddLoopPipelineAndVerificationPasses = [&] {
1413     LoopPassManager LPM(true);
1414     LPM.addPass(MLPHandle.getPass());
1415     LPM.addPass(MLPHandle.getPass());
1416     LPM.addPass(MLPHandle.getPass());
1417     FPM.addPass(createFunctionToLoopPassAdaptor(std::move(LPM)));
1418     FPM.addPass(DominatorTreeVerifierPass());
1419     FPM.addPass(LoopVerifierPass());
1420   };
1421
1422   // All the visit orders are deterministic so we use simple fully order
1423   // expectations.
1424   ::testing::InSequence MakeExpectationsSequenced;
1425
1426   // We run the loop pipeline with three passes over each of the loops. When
1427   // running over the middle loop, the second pass in the pipeline deletes it.
1428   // This should prevent the third pass from visiting it but otherwise leave
1429   // the process unimpacted.
1430   AddLoopPipelineAndVerificationPasses();
1431   EXPECT_CALL(MLPHandle, run(HasName("loop.0.0"), _, _, _))
1432       .WillOnce(Invoke(getLoopAnalysisResult));
1433   EXPECT_CALL(MLAHandle, run(HasName("loop.0.0"), _, _));
1434   EXPECT_CALL(MLPHandle, run(HasName("loop.0.0"), _, _, _))
1435       .Times(2)
1436       .WillRepeatedly(Invoke(getLoopAnalysisResult));
1437
1438   EXPECT_CALL(MLPHandle, run(HasName("loop.0.1"), _, _, _))
1439       .WillOnce(Invoke(getLoopAnalysisResult));
1440   EXPECT_CALL(MLAHandle, run(HasName("loop.0.1"), _, _));
1441   EXPECT_CALL(MLPHandle, run(HasName("loop.0.1"), _, _, _))
1442       .WillOnce(
1443           Invoke([&](Loop &L, LoopAnalysisManager &AM,
1444                      LoopStandardAnalysisResults &AR, LPMUpdater &Updater) {
1445             Loop *ParentL = L.getParentLoop();
1446             AR.SE.forgetLoop(&L);
1447             EraseLoop(L, Loop01PHBB, AR, Updater);
1448             ParentL->verifyLoop();
1449             return PreservedAnalyses::all();
1450           }));
1451
1452   EXPECT_CALL(MLPHandle, run(HasName("loop.0.2.0"), _, _, _))
1453       .WillOnce(Invoke(getLoopAnalysisResult));
1454   EXPECT_CALL(MLAHandle, run(HasName("loop.0.2.0"), _, _));
1455   EXPECT_CALL(MLPHandle, run(HasName("loop.0.2.0"), _, _, _))
1456       .Times(2)
1457       .WillRepeatedly(Invoke(getLoopAnalysisResult));
1458
1459   EXPECT_CALL(MLPHandle, run(HasName("loop.0.2"), _, _, _))
1460       .WillOnce(Invoke(getLoopAnalysisResult));
1461   EXPECT_CALL(MLAHandle, run(HasName("loop.0.2"), _, _));
1462   EXPECT_CALL(MLPHandle, run(HasName("loop.0.2"), _, _, _))
1463       .Times(2)
1464       .WillRepeatedly(Invoke(getLoopAnalysisResult));
1465
1466   EXPECT_CALL(MLPHandle, run(HasName("loop.0"), _, _, _))
1467       .WillOnce(Invoke(getLoopAnalysisResult));
1468   EXPECT_CALL(MLAHandle, run(HasName("loop.0"), _, _));
1469   EXPECT_CALL(MLPHandle, run(HasName("loop.0"), _, _, _))
1470       .Times(2)
1471       .WillRepeatedly(Invoke(getLoopAnalysisResult));
1472
1473   // Run the loop pipeline again. This time we delete the last loop, which
1474   // contains a nested loop within it and insert a new loop into the nest. This
1475   // makes sure we can handle nested loop deletion.
1476   AddLoopPipelineAndVerificationPasses();
1477   EXPECT_CALL(MLPHandle, run(HasName("loop.0.0"), _, _, _))
1478       .Times(3)
1479       .WillRepeatedly(Invoke(getLoopAnalysisResult));
1480
1481   EXPECT_CALL(MLPHandle, run(HasName("loop.0.2.0"), _, _, _))
1482       .Times(3)
1483       .WillRepeatedly(Invoke(getLoopAnalysisResult));
1484
1485   EXPECT_CALL(MLPHandle, run(HasName("loop.0.2"), _, _, _))
1486       .WillOnce(Invoke(getLoopAnalysisResult));
1487   BasicBlock *NewLoop03PHBB;
1488   EXPECT_CALL(MLPHandle, run(HasName("loop.0.2"), _, _, _))
1489       .WillOnce(
1490           Invoke([&](Loop &L, LoopAnalysisManager &AM,
1491                      LoopStandardAnalysisResults &AR, LPMUpdater &Updater) {
1492             AR.SE.forgetLoop(*L.begin());
1493             EraseLoop(**L.begin(), Loop020PHBB, AR, Updater);
1494
1495             auto *ParentL = L.getParentLoop();
1496             AR.SE.forgetLoop(&L);
1497             EraseLoop(L, Loop02PHBB, AR, Updater);
1498
1499             // Now insert a new sibling loop.
1500             auto *NewSibling = AR.LI.AllocateLoop();
1501             ParentL->addChildLoop(NewSibling);
1502             NewLoop03PHBB =
1503                 BasicBlock::Create(Context, "loop.0.3.ph", &F, &Loop0LatchBB);
1504             auto *NewLoop03BB =
1505                 BasicBlock::Create(Context, "loop.0.3", &F, &Loop0LatchBB);
1506             BranchInst::Create(NewLoop03BB, NewLoop03PHBB);
1507             auto *Cond =
1508                 new LoadInst(Type::getInt1Ty(Context), &Ptr, "cond.0.3",
1509                              /*isVolatile*/ true, NewLoop03BB);
1510             BranchInst::Create(&Loop0LatchBB, NewLoop03BB, Cond, NewLoop03BB);
1511             Loop02PHBB.getTerminator()->replaceUsesOfWith(&Loop0LatchBB,
1512                                                           NewLoop03PHBB);
1513             AR.DT.addNewBlock(NewLoop03PHBB, &Loop02PHBB);
1514             AR.DT.addNewBlock(NewLoop03BB, NewLoop03PHBB);
1515             AR.DT.changeImmediateDominator(AR.DT[&Loop0LatchBB],
1516                                            AR.DT[NewLoop03BB]);
1517             EXPECT_TRUE(AR.DT.verify());
1518             ParentL->addBasicBlockToLoop(NewLoop03PHBB, AR.LI);
1519             NewSibling->addBasicBlockToLoop(NewLoop03BB, AR.LI);
1520             NewSibling->verifyLoop();
1521             ParentL->verifyLoop();
1522             Updater.addSiblingLoops({NewSibling});
1523             return PreservedAnalyses::all();
1524           }));
1525
1526   // To respect our inner-to-outer traversal order, we must visit the
1527   // newly-inserted sibling of the loop we just deleted before we visit the
1528   // outer loop. When we do so, this must compute a fresh analysis result, even
1529   // though our new loop has the same pointer value as the loop we deleted.
1530   EXPECT_CALL(MLPHandle, run(HasName("loop.0.3"), _, _, _))
1531       .WillOnce(Invoke(getLoopAnalysisResult));
1532   EXPECT_CALL(MLAHandle, run(HasName("loop.0.3"), _, _));
1533   EXPECT_CALL(MLPHandle, run(HasName("loop.0.3"), _, _, _))
1534       .Times(2)
1535       .WillRepeatedly(Invoke(getLoopAnalysisResult));
1536
1537   EXPECT_CALL(MLPHandle, run(HasName("loop.0"), _, _, _))
1538       .Times(3)
1539       .WillRepeatedly(Invoke(getLoopAnalysisResult));
1540
1541   // In the final loop pipeline run we delete every loop, including the last
1542   // loop of the nest. We do this again in the second pass in the pipeline, and
1543   // as a consequence we never make it to three runs on any loop. We also cover
1544   // deleting multiple loops in a single pipeline, deleting the first loop and
1545   // deleting the (last) top level loop.
1546   AddLoopPipelineAndVerificationPasses();
1547   EXPECT_CALL(MLPHandle, run(HasName("loop.0.0"), _, _, _))
1548       .WillOnce(Invoke(getLoopAnalysisResult));
1549   EXPECT_CALL(MLPHandle, run(HasName("loop.0.0"), _, _, _))
1550       .WillOnce(
1551           Invoke([&](Loop &L, LoopAnalysisManager &AM,
1552                      LoopStandardAnalysisResults &AR, LPMUpdater &Updater) {
1553             AR.SE.forgetLoop(&L);
1554             EraseLoop(L, Loop00PHBB, AR, Updater);
1555             return PreservedAnalyses::all();
1556           }));
1557
1558   EXPECT_CALL(MLPHandle, run(HasName("loop.0.3"), _, _, _))
1559       .WillOnce(Invoke(getLoopAnalysisResult));
1560   EXPECT_CALL(MLPHandle, run(HasName("loop.0.3"), _, _, _))
1561       .WillOnce(
1562           Invoke([&](Loop &L, LoopAnalysisManager &AM,
1563                      LoopStandardAnalysisResults &AR, LPMUpdater &Updater) {
1564             AR.SE.forgetLoop(&L);
1565             EraseLoop(L, *NewLoop03PHBB, AR, Updater);
1566             return PreservedAnalyses::all();
1567           }));
1568
1569   EXPECT_CALL(MLPHandle, run(HasName("loop.0"), _, _, _))
1570       .WillOnce(Invoke(getLoopAnalysisResult));
1571   EXPECT_CALL(MLPHandle, run(HasName("loop.0"), _, _, _))
1572       .WillOnce(
1573           Invoke([&](Loop &L, LoopAnalysisManager &AM,
1574                      LoopStandardAnalysisResults &AR, LPMUpdater &Updater) {
1575             AR.SE.forgetLoop(&L);
1576             EraseLoop(L, EntryBB, AR, Updater);
1577             return PreservedAnalyses::all();
1578           }));
1579
1580   // Add the function pass pipeline now that it is fully built up and run it
1581   // over the module's one function.
1582   MPM.addPass(createModuleToFunctionPassAdaptor(std::move(FPM)));
1583   MPM.run(*M, MAM);
1584 }
1585 }