Add testcase for new feature for simplifycfg pass

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@5697 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/test/Transforms/SimplifyCFG/PhiBlockMerge.ll b/test/Transforms/SimplifyCFG/PhiBlockMerge.ll
new file mode 100644 (file)
index 0000000..d1df2a1
--- /dev/null
+++ b/test/Transforms/SimplifyCFG/PhiBlockMerge.ll
@@ -0,0 +1,26 @@
+; Test merging of blocks that only have PHI nodes in them
+;
+; RUN: if as < %s | opt -simplifycfg | dis | grep 'N:'
+; RUN: then exit 1
+; RUN: else exit 0
+; RUN: fi
+;
+
+int %test(bool %a, bool %b) {
+        br bool %a, label %M, label %O
+
+O:
+       br bool %b, label %N, label %Q
+Q:
+       br label %N
+N:
+       %Wp = phi int [0, %O], [1, %Q]
+       ; This block should be foldable into M
+       br label %M
+
+M:
+       %W = phi int [%Wp, %N], [2, %0]
+       %R = add int %W, 1
+       ret int %R
+}
+