Utils: Fix DomTree update for entry block
If SplitBlockPredecessors was used on a function entry block,
it wouldn't update the dominator tree.
llvm-svn: 323928
diff --git a/llvm/unittests/Transforms/Utils/BasicBlockUtils.cpp b/llvm/unittests/Transforms/Utils/BasicBlockUtils.cpp
new file mode 100644
index 0000000..2d0a930
--- /dev/null
+++ b/llvm/unittests/Transforms/Utils/BasicBlockUtils.cpp
@@ -0,0 +1,52 @@
+//===- BasicBlockUtils.cpp - Unit tests for BasicBlockUtils ---------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Transforms/Utils/BasicBlockUtils.h"
+#include "llvm/AsmParser/Parser.h"
+#include "llvm/IR/BasicBlock.h"
+#include "llvm/IR/Dominators.h"
+#include "llvm/IR/LLVMContext.h"
+#include "llvm/Support/SourceMgr.h"
+#include "gtest/gtest.h"
+
+using namespace llvm;
+
+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("BasicBlockUtilsTests", errs());
+ return Mod;
+}
+
+TEST(BasicBlockUtils, SplitBlockPredecessors) {
+ LLVMContext C;
+
+ std::unique_ptr<Module> M = parseIR(
+ C,
+ "define i32 @basic_func(i1 %cond) {\n"
+ "entry:\n"
+ " br i1 %cond, label %bb0, label %bb1\n"
+ "bb0:\n"
+ " br label %bb1\n"
+ "bb1:\n"
+ " %phi = phi i32 [ 0, %entry ], [ 1, %bb0 ]"
+ " ret i32 %phi\n"
+ "}\n"
+ "\n"
+ );
+
+ auto *F = M->getFunction("basic_func");
+ DominatorTree DT(*F);
+
+ // Make sure the dominator tree is properly updated if calling this on the
+ // entry block.
+ SplitBlockPredecessors(&F->getEntryBlock(), {}, "split.entry", &DT);
+ EXPECT_TRUE(DT.verify());
+}
diff --git a/llvm/unittests/Transforms/Utils/CMakeLists.txt b/llvm/unittests/Transforms/Utils/CMakeLists.txt
index e2bb0af..574e66f 100644
--- a/llvm/unittests/Transforms/Utils/CMakeLists.txt
+++ b/llvm/unittests/Transforms/Utils/CMakeLists.txt
@@ -8,6 +8,7 @@
add_llvm_unittest(UtilsTests
ASanStackFrameLayoutTest.cpp
+ BasicBlockUtils.cpp
Cloning.cpp
CodeExtractor.cpp
FunctionComparator.cpp
diff --git a/llvm/unittests/Transforms/Utils/Local.cpp b/llvm/unittests/Transforms/Utils/Local.cpp
index ab60122..9b305f73 100644
--- a/llvm/unittests/Transforms/Utils/Local.cpp
+++ b/llvm/unittests/Transforms/Utils/Local.cpp
@@ -100,7 +100,7 @@
EXPECT_EQ(3U, BB->size());
}
-std::unique_ptr<Module> parseIR(LLVMContext &C, const char *IR) {
+static std::unique_ptr<Module> parseIR(LLVMContext &C, const char *IR) {
SMDiagnostic Err;
std::unique_ptr<Module> Mod = parseAssemblyString(IR, Err, C);
if (!Mod)