Teach RecursivelyDeleteDeadPHINodes to handle multiple self-references. Patch
by Andrew Clinton!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126077 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/unittests/Transforms/Utils/Local.cpp b/unittests/Transforms/Utils/Local.cpp
new file mode 100644
index 0000000..e969e95
--- /dev/null
+++ b/unittests/Transforms/Utils/Local.cpp
@@ -0,0 +1,49 @@
+//===- 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 "gtest/gtest.h"
+#include "llvm/BasicBlock.h"
+#include "llvm/Instructions.h"
+#include "llvm/LLVMContext.h"
+#include "llvm/Support/IRBuilder.h"
+#include "llvm/Transforms/Utils/Local.h"
+
+using namespace llvm;
+
+TEST(Local, RecursivelyDeleteDeadPHINodes) {
+ LLVMContext &C(getGlobalContext());
+
+ 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));
+ 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);
+
+ bb0->dropAllReferences();
+ bb1->dropAllReferences();
+ delete bb0;
+ delete bb1;
+}