//===- ValueHandleTest.cpp - ValueHandle tests ----------------------------===// // // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. // See https://llvm.org/LICENSE.txt for license information. // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception // //===----------------------------------------------------------------------===// #include "llvm/IR/ValueHandle.h" #include "llvm/IR/Constants.h" #include "llvm/IR/Instructions.h" #include "llvm/IR/LLVMContext.h" #include "gtest/gtest.h" #include using namespace llvm; namespace { class ValueHandle : public testing::Test { protected: LLVMContext Context; Constant *ConstantV; std::unique_ptr BitcastV; ValueHandle() : ConstantV(ConstantInt::get(Type::getInt32Ty(Context), 0)), BitcastV(new BitCastInst(ConstantV, Type::getInt32Ty(Context))) {} }; class ConcreteCallbackVH final : public CallbackVH { public: ConcreteCallbackVH(Value *V) : CallbackVH(V) {} }; TEST_F(ValueHandle, WeakVH_BasicOperation) { WeakVH WVH(BitcastV.get()); EXPECT_EQ(BitcastV.get(), WVH); WVH = ConstantV; EXPECT_EQ(ConstantV, WVH); // Make sure I can call a method on the underlying Value. It // doesn't matter which method. EXPECT_EQ(Type::getInt32Ty(Context), WVH->getType()); EXPECT_EQ(Type::getInt32Ty(Context), (*WVH).getType()); WVH = BitcastV.get(); BitcastV->replaceAllUsesWith(ConstantV); EXPECT_EQ(WVH, BitcastV.get()); BitcastV.reset(); EXPECT_EQ(WVH, nullptr); } TEST_F(ValueHandle, WeakTrackingVH_BasicOperation) { WeakTrackingVH WVH(BitcastV.get()); EXPECT_EQ(BitcastV.get(), WVH); WVH = ConstantV; EXPECT_EQ(ConstantV, WVH); // Make sure I can call a method on the underlying Value. It // doesn't matter which method. EXPECT_EQ(Type::getInt32Ty(Context), WVH->getType()); EXPECT_EQ(Type::getInt32Ty(Context), (*WVH).getType()); } TEST_F(ValueHandle, WeakTrackingVH_Comparisons) { WeakTrackingVH BitcastWVH(BitcastV.get()); WeakTrackingVH ConstantWVH(ConstantV); EXPECT_TRUE(BitcastWVH == BitcastWVH); EXPECT_TRUE(BitcastV.get() == BitcastWVH); EXPECT_TRUE(BitcastWVH == BitcastV.get()); EXPECT_FALSE(BitcastWVH == ConstantWVH); EXPECT_TRUE(BitcastWVH != ConstantWVH); EXPECT_TRUE(BitcastV.get() != ConstantWVH); EXPECT_TRUE(BitcastWVH != ConstantV); EXPECT_FALSE(BitcastWVH != BitcastWVH); // Cast to Value* so comparisons work. Value *BV = BitcastV.get(); Value *CV = ConstantV; EXPECT_EQ(BV < CV, BitcastWVH < ConstantWVH); EXPECT_EQ(BV <= CV, BitcastWVH <= ConstantWVH); EXPECT_EQ(BV > CV, BitcastWVH > ConstantWVH); EXPECT_EQ(BV >= CV, BitcastWVH >= ConstantWVH); EXPECT_EQ(BV < CV, BitcastV.get() < ConstantWVH); EXPECT_EQ(BV <= CV, BitcastV.get() <= ConstantWVH); EXPECT_EQ(BV > CV, BitcastV.get() > ConstantWVH); EXPECT_EQ(BV >= CV, BitcastV.get() >= ConstantWVH); EXPECT_EQ(BV < CV, BitcastWVH < ConstantV); EXPECT_EQ(BV <= CV, BitcastWVH <= ConstantV); EXPECT_EQ(BV > CV, BitcastWVH > ConstantV); EXPECT_EQ(BV >= CV, BitcastWVH >= ConstantV); } TEST_F(ValueHandle, WeakTrackingVH_FollowsRAUW) { WeakTrackingVH WVH(BitcastV.get()); WeakTrackingVH WVH_Copy(WVH); WeakTrackingVH WVH_Recreated(BitcastV.get()); BitcastV->replaceAllUsesWith(ConstantV); EXPECT_EQ(ConstantV, WVH); EXPECT_EQ(ConstantV, WVH_Copy); EXPECT_EQ(ConstantV, WVH_Recreated); } TEST_F(ValueHandle, WeakTrackingVH_NullOnDeletion) { WeakTrackingVH WVH(BitcastV.get()); WeakTrackingVH WVH_Copy(WVH); WeakTrackingVH WVH_Recreated(BitcastV.get()); BitcastV.reset(); Value *null_value = nullptr; EXPECT_EQ(null_value, WVH); EXPECT_EQ(null_value, WVH_Copy); EXPECT_EQ(null_value, WVH_Recreated); } TEST_F(ValueHandle, AssertingVH_BasicOperation) { AssertingVH AVH(BitcastV.get()); CastInst *implicit_to_exact_type = AVH; (void)implicit_to_exact_type; // Avoid warning. AssertingVH GenericAVH(BitcastV.get()); EXPECT_EQ(BitcastV.get(), GenericAVH); GenericAVH = ConstantV; EXPECT_EQ(ConstantV, GenericAVH); // Make sure I can call a method on the underlying CastInst. It // doesn't matter which method. EXPECT_FALSE(AVH->mayWriteToMemory()); EXPECT_FALSE((*AVH).mayWriteToMemory()); } TEST_F(ValueHandle, AssertingVH_Const) { const CastInst *ConstBitcast = BitcastV.get(); AssertingVH AVH(ConstBitcast); const CastInst *implicit_to_exact_type = AVH; (void)implicit_to_exact_type; // Avoid warning. } TEST_F(ValueHandle, AssertingVH_Comparisons) { AssertingVH BitcastAVH(BitcastV.get()); AssertingVH ConstantAVH(ConstantV); EXPECT_TRUE(BitcastAVH == BitcastAVH); EXPECT_TRUE(BitcastV.get() == BitcastAVH); EXPECT_TRUE(BitcastAVH == BitcastV.get()); EXPECT_FALSE(BitcastAVH == ConstantAVH); EXPECT_TRUE(BitcastAVH != ConstantAVH); EXPECT_TRUE(BitcastV.get() != ConstantAVH); EXPECT_TRUE(BitcastAVH != ConstantV); EXPECT_FALSE(BitcastAVH != BitcastAVH); // Cast to Value* so comparisons work. Value *BV = BitcastV.get(); Value *CV = ConstantV; EXPECT_EQ(BV < CV, BitcastAVH < ConstantAVH); EXPECT_EQ(BV <= CV, BitcastAVH <= ConstantAVH); EXPECT_EQ(BV > CV, BitcastAVH > ConstantAVH); EXPECT_EQ(BV >= CV, BitcastAVH >= ConstantAVH); EXPECT_EQ(BV < CV, BitcastV.get() < ConstantAVH); EXPECT_EQ(BV <= CV, BitcastV.get() <= ConstantAVH); EXPECT_EQ(BV > CV, BitcastV.get() > ConstantAVH); EXPECT_EQ(BV >= CV, BitcastV.get() >= ConstantAVH); EXPECT_EQ(BV < CV, BitcastAVH < ConstantV); EXPECT_EQ(BV <= CV, BitcastAVH <= ConstantV); EXPECT_EQ(BV > CV, BitcastAVH > ConstantV); EXPECT_EQ(BV >= CV, BitcastAVH >= ConstantV); } TEST_F(ValueHandle, AssertingVH_DoesNotFollowRAUW) { AssertingVH AVH(BitcastV.get()); BitcastV->replaceAllUsesWith(ConstantV); EXPECT_EQ(BitcastV.get(), AVH); } #ifdef NDEBUG TEST_F(ValueHandle, AssertingVH_ReducesToPointer) { EXPECT_EQ(sizeof(CastInst *), sizeof(AssertingVH)); } #elif LLVM_ENABLE_ABI_BREAKING_CHECKS // && !NDEBUG #ifdef GTEST_HAS_DEATH_TEST TEST_F(ValueHandle, AssertingVH_Asserts) { AssertingVH AVH(BitcastV.get()); EXPECT_DEATH({BitcastV.reset();}, "An asserting value handle still pointed to this value!"); AssertingVH Copy(AVH); AVH = nullptr; EXPECT_DEATH({BitcastV.reset();}, "An asserting value handle still pointed to this value!"); Copy = nullptr; BitcastV.reset(); } #endif // GTEST_HAS_DEATH_TEST #endif // NDEBUG TEST_F(ValueHandle, CallbackVH_BasicOperation) { ConcreteCallbackVH CVH(BitcastV.get()); EXPECT_EQ(BitcastV.get(), CVH); CVH = ConstantV; EXPECT_EQ(ConstantV, CVH); // Make sure I can call a method on the underlying Value. It // doesn't matter which method. EXPECT_EQ(Type::getInt32Ty(Context), CVH->getType()); EXPECT_EQ(Type::getInt32Ty(Context), (*CVH).getType()); } TEST_F(ValueHandle, CallbackVH_Comparisons) { ConcreteCallbackVH BitcastCVH(BitcastV.get()); ConcreteCallbackVH ConstantCVH(ConstantV); EXPECT_TRUE(BitcastCVH == BitcastCVH); EXPECT_TRUE(BitcastV.get() == BitcastCVH); EXPECT_TRUE(BitcastCVH == BitcastV.get()); EXPECT_FALSE(BitcastCVH == ConstantCVH); EXPECT_TRUE(BitcastCVH != ConstantCVH); EXPECT_TRUE(BitcastV.get() != ConstantCVH); EXPECT_TRUE(BitcastCVH != ConstantV); EXPECT_FALSE(BitcastCVH != BitcastCVH); // Cast to Value* so comparisons work. Value *BV = BitcastV.get(); Value *CV = ConstantV; EXPECT_EQ(BV < CV, BitcastCVH < ConstantCVH); EXPECT_EQ(BV <= CV, BitcastCVH <= ConstantCVH); EXPECT_EQ(BV > CV, BitcastCVH > ConstantCVH); EXPECT_EQ(BV >= CV, BitcastCVH >= ConstantCVH); EXPECT_EQ(BV < CV, BitcastV.get() < ConstantCVH); EXPECT_EQ(BV <= CV, BitcastV.get() <= ConstantCVH); EXPECT_EQ(BV > CV, BitcastV.get() > ConstantCVH); EXPECT_EQ(BV >= CV, BitcastV.get() >= ConstantCVH); EXPECT_EQ(BV < CV, BitcastCVH < ConstantV); EXPECT_EQ(BV <= CV, BitcastCVH <= ConstantV); EXPECT_EQ(BV > CV, BitcastCVH > ConstantV); EXPECT_EQ(BV >= CV, BitcastCVH >= ConstantV); } TEST_F(ValueHandle, CallbackVH_CallbackOnDeletion) { class RecordingVH final : public CallbackVH { public: int DeletedCalls; int AURWCalls; RecordingVH() : DeletedCalls(0), AURWCalls(0) {} RecordingVH(Value *V) : CallbackVH(V), DeletedCalls(0), AURWCalls(0) {} private: void deleted() override { DeletedCalls++; CallbackVH::deleted(); } void allUsesReplacedWith(Value *) override { AURWCalls++; } }; RecordingVH RVH; RVH = BitcastV.get(); EXPECT_EQ(0, RVH.DeletedCalls); EXPECT_EQ(0, RVH.AURWCalls); BitcastV.reset(); EXPECT_EQ(1, RVH.DeletedCalls); EXPECT_EQ(0, RVH.AURWCalls); } TEST_F(ValueHandle, CallbackVH_CallbackOnRAUW) { class RecordingVH final : public CallbackVH { public: int DeletedCalls; Value *AURWArgument; RecordingVH() : DeletedCalls(0), AURWArgument(nullptr) {} RecordingVH(Value *V) : CallbackVH(V), DeletedCalls(0), AURWArgument(nullptr) {} private: void deleted() override { DeletedCalls++; CallbackVH::deleted(); } void allUsesReplacedWith(Value *new_value) override { EXPECT_EQ(nullptr, AURWArgument); AURWArgument = new_value; } }; RecordingVH RVH; RVH = BitcastV.get(); EXPECT_EQ(0, RVH.DeletedCalls); EXPECT_EQ(nullptr, RVH.AURWArgument); BitcastV->replaceAllUsesWith(ConstantV); EXPECT_EQ(0, RVH.DeletedCalls); EXPECT_EQ(ConstantV, RVH.AURWArgument); } TEST_F(ValueHandle, CallbackVH_DeletionCanRAUW) { class RecoveringVH final : public CallbackVH { public: int DeletedCalls; Value *AURWArgument; LLVMContext *Context; RecoveringVH(LLVMContext &TheContext) : DeletedCalls(0), AURWArgument(nullptr), Context(&TheContext) {} RecoveringVH(LLVMContext &TheContext, Value *V) : CallbackVH(V), DeletedCalls(0), AURWArgument(nullptr), Context(&TheContext) {} private: void deleted() override { getValPtr()->replaceAllUsesWith( Constant::getNullValue(Type::getInt32Ty(*Context))); setValPtr(nullptr); } void allUsesReplacedWith(Value *new_value) override { ASSERT_TRUE(nullptr != getValPtr()); EXPECT_EQ(1U, getValPtr()->getNumUses()); EXPECT_EQ(nullptr, AURWArgument); AURWArgument = new_value; } }; // Normally, if a value has uses, deleting it will crash. However, we can use // a CallbackVH to remove the uses before the check for no uses. RecoveringVH RVH(Context); RVH = RecoveringVH(Context, BitcastV.get()); std::unique_ptr BitcastUser(BinaryOperator::CreateAdd( RVH, Constant::getNullValue(Type::getInt32Ty(Context)))); EXPECT_EQ(BitcastV.get(), BitcastUser->getOperand(0)); BitcastV.reset(); // Would crash without the ValueHandler. EXPECT_EQ(Constant::getNullValue(Type::getInt32Ty(Context)), RVH.AURWArgument); EXPECT_EQ(Constant::getNullValue(Type::getInt32Ty(Context)), BitcastUser->getOperand(0)); } TEST_F(ValueHandle, DestroyingOtherVHOnSameValueDoesntBreakIteration) { // When a CallbackVH modifies other ValueHandles in its callbacks, // that shouldn't interfere with non-modified ValueHandles receiving // their appropriate callbacks. // // We create the active CallbackVH in the middle of a palindromic // arrangement of other VHs so that the bad behavior would be // triggered in whichever order callbacks run. class DestroyingVH final : public CallbackVH { public: std::unique_ptr ToClear[2]; DestroyingVH(Value *V) { ToClear[0].reset(new WeakTrackingVH(V)); setValPtr(V); ToClear[1].reset(new WeakTrackingVH(V)); } void deleted() override { ToClear[0].reset(); ToClear[1].reset(); CallbackVH::deleted(); } void allUsesReplacedWith(Value *) override { ToClear[0].reset(); ToClear[1].reset(); } }; { WeakTrackingVH ShouldBeVisited1(BitcastV.get()); DestroyingVH C(BitcastV.get()); WeakTrackingVH ShouldBeVisited2(BitcastV.get()); BitcastV->replaceAllUsesWith(ConstantV); EXPECT_EQ(ConstantV, static_cast(ShouldBeVisited1)); EXPECT_EQ(ConstantV, static_cast(ShouldBeVisited2)); } { WeakTrackingVH ShouldBeVisited1(BitcastV.get()); DestroyingVH C(BitcastV.get()); WeakTrackingVH ShouldBeVisited2(BitcastV.get()); BitcastV.reset(); EXPECT_EQ(nullptr, static_cast(ShouldBeVisited1)); EXPECT_EQ(nullptr, static_cast(ShouldBeVisited2)); } } TEST_F(ValueHandle, AssertingVHCheckedLast) { // If a CallbackVH exists to clear out a group of AssertingVHs on // Value deletion, the CallbackVH should get a chance to do so // before the AssertingVHs assert. class ClearingVH final : public CallbackVH { public: AssertingVH *ToClear[2]; ClearingVH(Value *V, AssertingVH &A0, AssertingVH &A1) : CallbackVH(V) { ToClear[0] = &A0; ToClear[1] = &A1; } void deleted() override { *ToClear[0] = nullptr; *ToClear[1] = nullptr; CallbackVH::deleted(); } }; AssertingVH A1, A2; A1 = BitcastV.get(); ClearingVH C(BitcastV.get(), A1, A2); A2 = BitcastV.get(); // C.deleted() should run first, clearing the two AssertingVHs, // which should prevent them from asserting. BitcastV.reset(); } TEST_F(ValueHandle, PoisoningVH_BasicOperation) { PoisoningVH VH(BitcastV.get()); CastInst *implicit_to_exact_type = VH; (void)implicit_to_exact_type; // Avoid warning. PoisoningVH GenericVH(BitcastV.get()); EXPECT_EQ(BitcastV.get(), GenericVH); GenericVH = ConstantV; EXPECT_EQ(ConstantV, GenericVH); // Make sure I can call a method on the underlying CastInst. It // doesn't matter which method. EXPECT_FALSE(VH->mayWriteToMemory()); EXPECT_FALSE((*VH).mayWriteToMemory()); } TEST_F(ValueHandle, PoisoningVH_Const) { const CastInst *ConstBitcast = BitcastV.get(); PoisoningVH VH(ConstBitcast); const CastInst *implicit_to_exact_type = VH; (void)implicit_to_exact_type; // Avoid warning. } TEST_F(ValueHandle, PoisoningVH_Comparisons) { PoisoningVH BitcastVH(BitcastV.get()); PoisoningVH ConstantVH(ConstantV); EXPECT_TRUE(BitcastVH == BitcastVH); EXPECT_TRUE(BitcastV.get() == BitcastVH); EXPECT_TRUE(BitcastVH == BitcastV.get()); EXPECT_FALSE(BitcastVH == ConstantVH); EXPECT_TRUE(BitcastVH != ConstantVH); EXPECT_TRUE(BitcastV.get() != ConstantVH); EXPECT_TRUE(BitcastVH != ConstantV); EXPECT_FALSE(BitcastVH != BitcastVH); // Cast to Value* so comparisons work. Value *BV = BitcastV.get(); Value *CV = ConstantV; EXPECT_EQ(BV < CV, BitcastVH < ConstantVH); EXPECT_EQ(BV <= CV, BitcastVH <= ConstantVH); EXPECT_EQ(BV > CV, BitcastVH > ConstantVH); EXPECT_EQ(BV >= CV, BitcastVH >= ConstantVH); EXPECT_EQ(BV < CV, BitcastV.get() < ConstantVH); EXPECT_EQ(BV <= CV, BitcastV.get() <= ConstantVH); EXPECT_EQ(BV > CV, BitcastV.get() > ConstantVH); EXPECT_EQ(BV >= CV, BitcastV.get() >= ConstantVH); EXPECT_EQ(BV < CV, BitcastVH < ConstantV); EXPECT_EQ(BV <= CV, BitcastVH <= ConstantV); EXPECT_EQ(BV > CV, BitcastVH > ConstantV); EXPECT_EQ(BV >= CV, BitcastVH >= ConstantV); } TEST_F(ValueHandle, PoisoningVH_DoesNotFollowRAUW) { PoisoningVH VH(BitcastV.get()); BitcastV->replaceAllUsesWith(ConstantV); EXPECT_TRUE(DenseMapInfo>::isEqual(VH, BitcastV.get())); } TEST_F(ValueHandle, AssertingVH_DenseMap) { DenseMap, int> Map; Map.insert({BitcastV.get(), 1}); Map.insert({ConstantV, 2}); // These will create a temporary AssertingVH during lookup. EXPECT_TRUE(Map.find(BitcastV.get()) != Map.end()); EXPECT_TRUE(Map.find(ConstantV) != Map.end()); // These will not create a temporary AssertingVH. EXPECT_TRUE(Map.find_as(BitcastV.get()) != Map.end()); EXPECT_TRUE(Map.find_as(ConstantV) != Map.end()); } TEST_F(ValueHandle, PoisoningVH_DenseMap) { DenseMap, int> Map; Map.insert({BitcastV.get(), 1}); Map.insert({ConstantV, 2}); // These will create a temporary PoisoningVH during lookup. EXPECT_TRUE(Map.find(BitcastV.get()) != Map.end()); EXPECT_TRUE(Map.find(ConstantV) != Map.end()); // These will not create a temporary PoisoningVH. EXPECT_TRUE(Map.find_as(BitcastV.get()) != Map.end()); EXPECT_TRUE(Map.find_as(ConstantV) != Map.end()); } #ifdef NDEBUG TEST_F(ValueHandle, PoisoningVH_ReducesToPointer) { EXPECT_EQ(sizeof(CastInst *), sizeof(PoisoningVH)); } #else // !NDEBUG TEST_F(ValueHandle, TrackingVH_Tracks) { TrackingVH VH(BitcastV.get()); BitcastV->replaceAllUsesWith(ConstantV); EXPECT_EQ(VH, ConstantV); } #ifdef GTEST_HAS_DEATH_TEST #if LLVM_ENABLE_ABI_BREAKING_CHECKS TEST_F(ValueHandle, PoisoningVH_Asserts) { PoisoningVH VH(BitcastV.get()); // The poisoned handle shouldn't assert when the value is deleted. BitcastV.reset(new BitCastInst(ConstantV, Type::getInt32Ty(Context))); // But should when we access the handle. EXPECT_DEATH((void)*VH, "Accessed a poisoned value handle!"); // Now check that poison catches RAUW. VH = BitcastV.get(); // The replace doesn't trigger anything immediately. BitcastV->replaceAllUsesWith(ConstantV); // But a use does. EXPECT_DEATH((void)*VH, "Accessed a poisoned value handle!"); // Don't clear anything out here as destroying the handles should be fine. } #endif // LLVM_ENABLE_ABI_BREAKING_CHECKS TEST_F(ValueHandle, TrackingVH_Asserts) { { TrackingVH VH(BitcastV.get()); // The tracking handle shouldn't assert when the value is deleted. BitcastV.reset(new BitCastInst(ConstantV, Type::getInt32Ty(Context))); // But should when we access the handle. EXPECT_DEATH((void)*VH, "TrackingVH must be non-null and valid on dereference!"); } { TrackingVH VH(BitcastV.get()); BitcastV->replaceAllUsesWith(ConstantV); EXPECT_DEATH((void)*VH, "Tracked Value was replaced by one with an invalid type!"); } } #endif // GTEST_HAS_DEATH_TEST #endif // NDEBUG }