Testcase that Nate found where LoopUnswitch chokes on eliminating a dead case

from a switch instruction.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28946 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/test/Transforms/LoopUnswitch/2006-06-27-DeadSwitchCase.ll b/test/Transforms/LoopUnswitch/2006-06-27-DeadSwitchCase.ll
new file mode 100644 (file)
index 0000000..b7c6df8
--- /dev/null
+++ b/test/Transforms/LoopUnswitch/2006-06-27-DeadSwitchCase.ll
@@ -0,0 +1,31 @@
+; RUN: llvm-as < %s | opt -loop-unswitch -disable-output
+implementation   ; Functions:
+
+void %init_caller_save() {
+entry:
+       br label %cond_true78
+
+cond_next20:           ; preds = %cond_true64
+       br label %bb31
+
+bb31:          ; preds = %cond_true64, %cond_true64, %cond_next20
+       %iftmp.29.1 = phi uint [ 0, %cond_next20 ], [ 0, %cond_true64 ], [ 0, %cond_true64 ]            ; <uint> [#uses=0]
+       br label %bb54
+
+bb54:          ; preds = %cond_true78, %bb31
+       br bool false, label %bb75, label %cond_true64
+
+cond_true64:           ; preds = %bb54
+       switch int %i.0.0, label %cond_next20 [
+                int 17, label %bb31
+                int 18, label %bb31
+       ]
+
+bb75:          ; preds = %bb54
+       %tmp74.0 = add int %i.0.0, 1            ; <int> [#uses=1]
+       br label %cond_true78
+
+cond_true78:           ; preds = %bb75, %entry
+       %i.0.0 = phi int [ 0, %entry ], [ %tmp74.0, %bb75 ]             ; <int> [#uses=2]
+       br label %bb54
+}