1 //===- Local.cpp - Unit tests for Local -----------------------------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9
10 #include "llvm/Transforms/Utils/Local.h"
11 #include "llvm/IR/BasicBlock.h"
12 #include "llvm/IR/IRBuilder.h"
13 #include "llvm/IR/Instructions.h"
14 #include "llvm/IR/LLVMContext.h"
15 #include "gtest/gtest.h"
16
17 using namespace llvm;
18
TEST(Local,RecursivelyDeleteDeadPHINodes)19 TEST(Local, RecursivelyDeleteDeadPHINodes) {
20 LLVMContext &C(getGlobalContext());
21
22 IRBuilder<> builder(C);
23
24 // Make blocks
25 BasicBlock *bb0 = BasicBlock::Create(C);
26 BasicBlock *bb1 = BasicBlock::Create(C);
27
28 builder.SetInsertPoint(bb0);
29 PHINode *phi = builder.CreatePHI(Type::getInt32Ty(C), 2);
30 BranchInst *br0 = builder.CreateCondBr(builder.getTrue(), bb0, bb1);
31
32 builder.SetInsertPoint(bb1);
33 BranchInst *br1 = builder.CreateBr(bb0);
34
35 phi->addIncoming(phi, bb0);
36 phi->addIncoming(phi, bb1);
37
38 // The PHI will be removed
39 EXPECT_TRUE(RecursivelyDeleteDeadPHINode(phi));
40
41 // Make sure the blocks only contain the branches
42 EXPECT_EQ(&bb0->front(), br0);
43 EXPECT_EQ(&bb1->front(), br1);
44
45 builder.SetInsertPoint(bb0);
46 phi = builder.CreatePHI(Type::getInt32Ty(C), 0);
47
48 EXPECT_TRUE(RecursivelyDeleteDeadPHINode(phi));
49
50 builder.SetInsertPoint(bb0);
51 phi = builder.CreatePHI(Type::getInt32Ty(C), 0);
52 builder.CreateAdd(phi, phi);
53
54 EXPECT_TRUE(RecursivelyDeleteDeadPHINode(phi));
55
56 bb0->dropAllReferences();
57 bb1->dropAllReferences();
58 delete bb0;
59 delete bb1;
60 }
61
TEST(Local,RemoveDuplicatePHINodes)62 TEST(Local, RemoveDuplicatePHINodes) {
63 LLVMContext &C(getGlobalContext());
64 IRBuilder<> B(C);
65
66 std::unique_ptr<Function> F(
67 Function::Create(FunctionType::get(B.getVoidTy(), false),
68 GlobalValue::ExternalLinkage, "F"));
69 BasicBlock *Entry(BasicBlock::Create(C, "", F.get()));
70 BasicBlock *BB(BasicBlock::Create(C, "", F.get()));
71 BranchInst::Create(BB, Entry);
72
73 B.SetInsertPoint(BB);
74
75 AssertingVH<PHINode> P1 = B.CreatePHI(Type::getInt32Ty(C), 2);
76 P1->addIncoming(B.getInt32(42), Entry);
77
78 PHINode *P2 = B.CreatePHI(Type::getInt32Ty(C), 2);
79 P2->addIncoming(B.getInt32(42), Entry);
80
81 AssertingVH<PHINode> P3 = B.CreatePHI(Type::getInt32Ty(C), 2);
82 P3->addIncoming(B.getInt32(42), Entry);
83 P3->addIncoming(B.getInt32(23), BB);
84
85 PHINode *P4 = B.CreatePHI(Type::getInt32Ty(C), 2);
86 P4->addIncoming(B.getInt32(42), Entry);
87 P4->addIncoming(B.getInt32(23), BB);
88
89 P1->addIncoming(P3, BB);
90 P2->addIncoming(P4, BB);
91 BranchInst::Create(BB, BB);
92
93 // Verify that we can eliminate PHIs that become duplicates after chaning PHIs
94 // downstream.
95 EXPECT_TRUE(EliminateDuplicatePHINodes(BB));
96 EXPECT_EQ(3U, BB->size());
97 }
98