| //===- Local.cpp - Unit tests for Local -----------------------------------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "llvm/Analysis/Utils/Local.h" |
| #include "llvm/AsmParser/Parser.h" |
| #include "llvm/IR/BasicBlock.h" |
| #include "llvm/IR/DIBuilder.h" |
| #include "llvm/IR/IRBuilder.h" |
| #include "llvm/IR/Instructions.h" |
| #include "llvm/IR/IntrinsicInst.h" |
| #include "llvm/IR/LLVMContext.h" |
| #include "llvm/Support/SourceMgr.h" |
| #include "gtest/gtest.h" |
| |
| using namespace llvm; |
| |
| TEST(Local, RecursivelyDeleteDeadPHINodes) { |
| LLVMContext C; |
| |
| IRBuilder<> builder(C); |
| |
| // Make blocks |
| BasicBlock *bb0 = BasicBlock::Create(C); |
| BasicBlock *bb1 = BasicBlock::Create(C); |
| |
| builder.SetInsertPoint(bb0); |
| PHINode *phi = builder.CreatePHI(Type::getInt32Ty(C), 2); |
| BranchInst *br0 = builder.CreateCondBr(builder.getTrue(), bb0, bb1); |
| |
| builder.SetInsertPoint(bb1); |
| BranchInst *br1 = builder.CreateBr(bb0); |
| |
| phi->addIncoming(phi, bb0); |
| phi->addIncoming(phi, bb1); |
| |
| // The PHI will be removed |
| EXPECT_TRUE(RecursivelyDeleteDeadPHINode(phi)); |
| |
| // Make sure the blocks only contain the branches |
| EXPECT_EQ(&bb0->front(), br0); |
| EXPECT_EQ(&bb1->front(), br1); |
| |
| builder.SetInsertPoint(bb0); |
| phi = builder.CreatePHI(Type::getInt32Ty(C), 0); |
| |
| EXPECT_TRUE(RecursivelyDeleteDeadPHINode(phi)); |
| |
| builder.SetInsertPoint(bb0); |
| phi = builder.CreatePHI(Type::getInt32Ty(C), 0); |
| builder.CreateAdd(phi, phi); |
| |
| EXPECT_TRUE(RecursivelyDeleteDeadPHINode(phi)); |
| |
| bb0->dropAllReferences(); |
| bb1->dropAllReferences(); |
| delete bb0; |
| delete bb1; |
| } |
| |
| TEST(Local, RemoveDuplicatePHINodes) { |
| LLVMContext C; |
| IRBuilder<> B(C); |
| |
| std::unique_ptr<Function> F( |
| Function::Create(FunctionType::get(B.getVoidTy(), false), |
| GlobalValue::ExternalLinkage, "F")); |
| BasicBlock *Entry(BasicBlock::Create(C, "", F.get())); |
| BasicBlock *BB(BasicBlock::Create(C, "", F.get())); |
| BranchInst::Create(BB, Entry); |
| |
| B.SetInsertPoint(BB); |
| |
| AssertingVH<PHINode> P1 = B.CreatePHI(Type::getInt32Ty(C), 2); |
| P1->addIncoming(B.getInt32(42), Entry); |
| |
| PHINode *P2 = B.CreatePHI(Type::getInt32Ty(C), 2); |
| P2->addIncoming(B.getInt32(42), Entry); |
| |
| AssertingVH<PHINode> P3 = B.CreatePHI(Type::getInt32Ty(C), 2); |
| P3->addIncoming(B.getInt32(42), Entry); |
| P3->addIncoming(B.getInt32(23), BB); |
| |
| PHINode *P4 = B.CreatePHI(Type::getInt32Ty(C), 2); |
| P4->addIncoming(B.getInt32(42), Entry); |
| P4->addIncoming(B.getInt32(23), BB); |
| |
| P1->addIncoming(P3, BB); |
| P2->addIncoming(P4, BB); |
| BranchInst::Create(BB, BB); |
| |
| // Verify that we can eliminate PHIs that become duplicates after chaning PHIs |
| // downstream. |
| EXPECT_TRUE(EliminateDuplicatePHINodes(BB)); |
| EXPECT_EQ(3U, BB->size()); |
| } |
| |
| static std::unique_ptr<Module> parseIR(LLVMContext &C, const char *IR) { |
| SMDiagnostic Err; |
| std::unique_ptr<Module> Mod = parseAssemblyString(IR, Err, C); |
| if (!Mod) |
| Err.print("UtilsTests", errs()); |
| return Mod; |
| } |
| |
| TEST(Local, ReplaceDbgDeclare) { |
| LLVMContext C; |
| |
| // Original C source to get debug info for a local variable: |
| // void f() { int x; } |
| std::unique_ptr<Module> M = parseIR(C, |
| R"( |
| define void @f() !dbg !8 { |
| entry: |
| %x = alloca i32, align 4 |
| call void @llvm.dbg.declare(metadata i32* %x, metadata !11, metadata !DIExpression()), !dbg !13 |
| call void @llvm.dbg.declare(metadata i32* %x, metadata !11, metadata !DIExpression()), !dbg !13 |
| ret void, !dbg !14 |
| } |
| declare void @llvm.dbg.declare(metadata, metadata, metadata) |
| !llvm.dbg.cu = !{!0} |
| !llvm.module.flags = !{!3, !4} |
| !0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 6.0.0", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !2) |
| !1 = !DIFile(filename: "t2.c", directory: "foo") |
| !2 = !{} |
| !3 = !{i32 2, !"Dwarf Version", i32 4} |
| !4 = !{i32 2, !"Debug Info Version", i32 3} |
| !8 = distinct !DISubprogram(name: "f", scope: !1, file: !1, line: 1, type: !9, isLocal: false, isDefinition: true, scopeLine: 1, isOptimized: false, unit: !0, variables: !2) |
| !9 = !DISubroutineType(types: !10) |
| !10 = !{null} |
| !11 = !DILocalVariable(name: "x", scope: !8, file: !1, line: 2, type: !12) |
| !12 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed) |
| !13 = !DILocation(line: 2, column: 7, scope: !8) |
| !14 = !DILocation(line: 3, column: 1, scope: !8) |
| )"); |
| auto *GV = M->getNamedValue("f"); |
| ASSERT_TRUE(GV); |
| auto *F = dyn_cast<Function>(GV); |
| ASSERT_TRUE(F); |
| Instruction *Inst = &F->front().front(); |
| auto *AI = dyn_cast<AllocaInst>(Inst); |
| ASSERT_TRUE(AI); |
| Inst = Inst->getNextNode()->getNextNode(); |
| ASSERT_TRUE(Inst); |
| auto *DII = dyn_cast<DbgDeclareInst>(Inst); |
| ASSERT_TRUE(DII); |
| Value *NewBase = Constant::getNullValue(Type::getInt32PtrTy(C)); |
| DIBuilder DIB(*M); |
| replaceDbgDeclare(AI, NewBase, DII, DIB, DIExpression::NoDeref, 0, |
| DIExpression::NoDeref); |
| |
| // There should be exactly two dbg.declares. |
| int Declares = 0; |
| for (const Instruction &I : F->front()) |
| if (isa<DbgDeclareInst>(I)) |
| Declares++; |
| EXPECT_EQ(2, Declares); |
| } |
| |
| /// Build the dominator tree for the function and run the Test. |
| static void runWithDomTree( |
| Module &M, StringRef FuncName, |
| function_ref<void(Function &F, DominatorTree *DT)> Test) { |
| auto *F = M.getFunction(FuncName); |
| ASSERT_NE(F, nullptr) << "Could not find " << FuncName; |
| // Compute the dominator tree for the function. |
| DominatorTree DT(*F); |
| Test(*F, &DT); |
| } |
| |
| TEST(Local, MergeBasicBlockIntoOnlyPred) { |
| LLVMContext C; |
| |
| std::unique_ptr<Module> M = parseIR(C, |
| R"( |
| define i32 @f(i8* %str) { |
| entry: |
| br label %bb2.i |
| bb2.i: ; preds = %bb4.i, %entry |
| br i1 false, label %bb4.i, label %base2flt.exit204 |
| bb4.i: ; preds = %bb2.i |
| br i1 false, label %base2flt.exit204, label %bb2.i |
| bb10.i196.bb7.i197_crit_edge: ; No predecessors! |
| br label %bb7.i197 |
| bb7.i197: ; preds = %bb10.i196.bb7.i197_crit_edge |
| %.reg2mem.0 = phi i32 [ %.reg2mem.0, %bb10.i196.bb7.i197_crit_edge ] |
| br i1 undef, label %base2flt.exit204, label %base2flt.exit204 |
| base2flt.exit204: ; preds = %bb7.i197, %bb7.i197, %bb2.i, %bb4.i |
| ret i32 0 |
| } |
| )"); |
| runWithDomTree( |
| *M, "f", [&](Function &F, DominatorTree *DT) { |
| for (Function::iterator I = F.begin(), E = F.end(); I != E;) { |
| BasicBlock *BB = &*I++; |
| BasicBlock *SinglePred = BB->getSinglePredecessor(); |
| if (!SinglePred || SinglePred == BB || BB->hasAddressTaken()) continue; |
| BranchInst *Term = dyn_cast<BranchInst>(SinglePred->getTerminator()); |
| if (Term && !Term->isConditional()) |
| MergeBasicBlockIntoOnlyPred(BB, DT); |
| } |
| EXPECT_TRUE(DT->verify()); |
| }); |
| } |
| |
| TEST(Local, ConstantFoldTerminator) { |
| LLVMContext C; |
| |
| std::unique_ptr<Module> M = parseIR(C, |
| R"( |
| define void @br_same_dest() { |
| entry: |
| br i1 false, label %bb0, label %bb0 |
| bb0: |
| ret void |
| } |
| |
| define void @br_different_dest() { |
| entry: |
| br i1 true, label %bb0, label %bb1 |
| bb0: |
| br label %exit |
| bb1: |
| br label %exit |
| exit: |
| ret void |
| } |
| |
| define void @switch_2_different_dest() { |
| entry: |
| switch i32 0, label %default [ i32 0, label %bb0 ] |
| default: |
| ret void |
| bb0: |
| ret void |
| } |
| define void @switch_2_different_dest_default() { |
| entry: |
| switch i32 1, label %default [ i32 0, label %bb0 ] |
| default: |
| ret void |
| bb0: |
| ret void |
| } |
| define void @switch_3_different_dest() { |
| entry: |
| switch i32 0, label %default [ i32 0, label %bb0 |
| i32 1, label %bb1 ] |
| default: |
| ret void |
| bb0: |
| ret void |
| bb1: |
| ret void |
| } |
| |
| define void @switch_variable_2_default_dest(i32 %arg) { |
| entry: |
| switch i32 %arg, label %default [ i32 0, label %default ] |
| default: |
| ret void |
| } |
| |
| define void @switch_constant_2_default_dest() { |
| entry: |
| switch i32 1, label %default [ i32 0, label %default ] |
| default: |
| ret void |
| } |
| |
| define void @switch_constant_3_repeated_dest() { |
| entry: |
| switch i32 0, label %default [ i32 0, label %bb0 |
| i32 1, label %bb0 ] |
| bb0: |
| ret void |
| default: |
| ret void |
| } |
| |
| define void @indirectbr() { |
| entry: |
| indirectbr i8* blockaddress(@indirectbr, %bb0), [label %bb0, label %bb1] |
| bb0: |
| ret void |
| bb1: |
| ret void |
| } |
| |
| define void @indirectbr_repeated() { |
| entry: |
| indirectbr i8* blockaddress(@indirectbr_repeated, %bb0), [label %bb0, label %bb0] |
| bb0: |
| ret void |
| } |
| |
| define void @indirectbr_unreachable() { |
| entry: |
| indirectbr i8* blockaddress(@indirectbr_unreachable, %bb0), [label %bb1] |
| bb0: |
| ret void |
| bb1: |
| ret void |
| } |
| )"); |
| |
| auto CFAllTerminators = [&](Function &F, DominatorTree *DT) { |
| DeferredDominance DDT(*DT); |
| for (Function::iterator I = F.begin(), E = F.end(); I != E;) { |
| BasicBlock *BB = &*I++; |
| ConstantFoldTerminator(BB, true, nullptr, &DDT); |
| } |
| |
| EXPECT_TRUE(DDT.flush().verify()); |
| }; |
| |
| runWithDomTree(*M, "br_same_dest", CFAllTerminators); |
| runWithDomTree(*M, "br_different_dest", CFAllTerminators); |
| runWithDomTree(*M, "switch_2_different_dest", CFAllTerminators); |
| runWithDomTree(*M, "switch_2_different_dest_default", CFAllTerminators); |
| runWithDomTree(*M, "switch_3_different_dest", CFAllTerminators); |
| runWithDomTree(*M, "switch_variable_2_default_dest", CFAllTerminators); |
| runWithDomTree(*M, "switch_constant_2_default_dest", CFAllTerminators); |
| runWithDomTree(*M, "switch_constant_3_repeated_dest", CFAllTerminators); |
| runWithDomTree(*M, "indirectbr", CFAllTerminators); |
| runWithDomTree(*M, "indirectbr_repeated", CFAllTerminators); |
| runWithDomTree(*M, "indirectbr_unreachable", CFAllTerminators); |
| } |
| |
| struct SalvageDebugInfoTest : ::testing::Test { |
| LLVMContext C; |
| std::unique_ptr<Module> M; |
| Function *F = nullptr; |
| |
| void SetUp() { |
| M = parseIR(C, |
| R"( |
| define void @f() !dbg !8 { |
| entry: |
| %x = add i32 0, 1 |
| %y = add i32 %x, 2 |
| call void @llvm.dbg.value(metadata i32 %x, metadata !11, metadata !DIExpression()), !dbg !13 |
| call void @llvm.dbg.value(metadata i32 %y, metadata !11, metadata !DIExpression()), !dbg !13 |
| ret void, !dbg !14 |
| } |
| declare void @llvm.dbg.value(metadata, metadata, metadata) |
| !llvm.dbg.cu = !{!0} |
| !llvm.module.flags = !{!3, !4} |
| !0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 6.0.0", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !2) |
| !1 = !DIFile(filename: "t2.c", directory: "foo") |
| !2 = !{} |
| !3 = !{i32 2, !"Dwarf Version", i32 4} |
| !4 = !{i32 2, !"Debug Info Version", i32 3} |
| !8 = distinct !DISubprogram(name: "f", scope: !1, file: !1, line: 1, type: !9, isLocal: false, isDefinition: true, scopeLine: 1, isOptimized: false, unit: !0, variables: !2) |
| !9 = !DISubroutineType(types: !10) |
| !10 = !{null} |
| !11 = !DILocalVariable(name: "x", scope: !8, file: !1, line: 2, type: !12) |
| !12 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed) |
| !13 = !DILocation(line: 2, column: 7, scope: !8) |
| !14 = !DILocation(line: 3, column: 1, scope: !8) |
| )"); |
| |
| auto *GV = M->getNamedValue("f"); |
| ASSERT_TRUE(GV); |
| F = dyn_cast<Function>(GV); |
| ASSERT_TRUE(F); |
| } |
| |
| bool doesDebugValueDescribeX(const DbgValueInst &DI) { |
| const auto &CI = *cast<ConstantInt>(DI.getValue()); |
| if (CI.isZero()) |
| return DI.getExpression()->getElements().equals( |
| {dwarf::DW_OP_plus_uconst, 1, dwarf::DW_OP_stack_value}); |
| else if (CI.isOneValue()) |
| return DI.getExpression()->getElements().empty(); |
| return false; |
| } |
| |
| bool doesDebugValueDescribeY(const DbgValueInst &DI) { |
| const auto &CI = *cast<ConstantInt>(DI.getValue()); |
| if (CI.isZero()) |
| return DI.getExpression()->getElements().equals( |
| {dwarf::DW_OP_plus_uconst, 1, dwarf::DW_OP_plus_uconst, 2, |
| dwarf::DW_OP_stack_value}); |
| else if (CI.isOneValue()) |
| return DI.getExpression()->getElements().equals( |
| {dwarf::DW_OP_plus_uconst, 2, dwarf::DW_OP_stack_value}); |
| return false; |
| } |
| |
| void verifyDebugValuesAreSalvaged() { |
| // Check that the debug values for %x and %y are preserved. |
| bool FoundX = false; |
| bool FoundY = false; |
| for (const Instruction &I : F->front()) { |
| auto DI = dyn_cast<DbgValueInst>(&I); |
| if (!DI) { |
| // The function should only contain debug values and a terminator. |
| ASSERT_TRUE(isa<TerminatorInst>(&I)); |
| continue; |
| } |
| EXPECT_EQ(DI->getVariable()->getName(), "x"); |
| FoundX |= doesDebugValueDescribeX(*DI); |
| FoundY |= doesDebugValueDescribeY(*DI); |
| } |
| ASSERT_TRUE(FoundX); |
| ASSERT_TRUE(FoundY); |
| } |
| }; |
| |
| TEST_F(SalvageDebugInfoTest, RecursiveInstDeletion) { |
| Instruction *Inst = &F->front().front(); |
| Inst = Inst->getNextNode(); // Get %y = add ... |
| ASSERT_TRUE(Inst); |
| bool Deleted = RecursivelyDeleteTriviallyDeadInstructions(Inst); |
| ASSERT_TRUE(Deleted); |
| verifyDebugValuesAreSalvaged(); |
| } |
| |
| TEST_F(SalvageDebugInfoTest, RecursiveBlockSimplification) { |
| BasicBlock *BB = &F->front(); |
| ASSERT_TRUE(BB); |
| bool Deleted = SimplifyInstructionsInBlock(BB); |
| ASSERT_TRUE(Deleted); |
| verifyDebugValuesAreSalvaged(); |
| } |