Add a testcase to help test analysis preservation.

llvm-svn: 83002

1 files changed, 47 insertions, 0 deletions

diff --git a/llvm/test/Transforms/LoopRotate/preserve-scev.ll b/llvm/test/Transforms/LoopRotate/preserve-scev.ll
new file mode 100644
index 00000000000..9eedaa49c0b
--- /dev/null
+++ b/llvm/test/Transforms/LoopRotate/preserve-scev.ll
@@ -0,0 +1,47 @@
+; RUN: opt < %s -loop-rotate -loop-reduce -disable-output
+
+define fastcc void @foo() nounwind {
+BB:
+  br label %BB1
+
+BB1:                                              ; preds = %BB19, %BB
+  br label %BB4
+
+BB2:                                              ; preds = %BB4
+  %tmp = bitcast i32 undef to i32                 ; <i32> [#uses=1]
+  br label %BB4
+
+BB4:                                              ; preds = %BB3, %BB1
+  %tmp5 = phi i32 [ undef, %BB1 ], [ %tmp, %BB2 ] ; <i32> [#uses=1]
+  br i1 false, label %BB8, label %BB2
+
+BB8:                                              ; preds = %BB6
+  %tmp7 = bitcast i32 %tmp5 to i32                ; <i32> [#uses=2]
+  br i1 false, label %BB9, label %BB13
+
+BB9:                                              ; preds = %BB12, %BB8
+  %tmp10 = phi i32 [ %tmp11, %BB12 ], [ %tmp7, %BB8 ] ; <i32> [#uses=2]
+  %tmp11 = add i32 %tmp10, 1                      ; <i32> [#uses=1]
+  br label %BB12
+
+BB12:                                             ; preds = %BB9
+  br i1 false, label %BB9, label %BB17
+
+BB13:                                             ; preds = %BB15, %BB8
+  %tmp14 = phi i32 [ %tmp16, %BB15 ], [ %tmp7, %BB8 ] ; <i32> [#uses=1]
+  br label %BB15
+
+BB15:                                             ; preds = %BB13
+  %tmp16 = add i32 %tmp14, -1                     ; <i32> [#uses=1]
+  br i1 false, label %BB13, label %BB18
+
+BB17:                                             ; preds = %BB12
+  br label %BB19
+
+BB18:                                             ; preds = %BB15
+  br label %BB19
+
+BB19:                                             ; preds = %BB18, %BB17
+  %tmp20 = phi i32 [ %tmp10, %BB17 ], [ undef, %BB18 ] ; <i32> [#uses=0]
+  br label %BB1
+}