don't call MergeBasicBlockIntoOnlyPred on a block whose only

predecessor is itself.  This doesn't make sense, and this is
a dead infinite loop anyway.

llvm-svn: 60210

1 files changed, 17 insertions, 0 deletions

diff --git a/llvm/test/Transforms/JumpThreading/2008-11-28-InfLoop.ll b/llvm/test/Transforms/JumpThreading/2008-11-28-InfLoop.ll
new file mode 100644
index 00000000000..974b9ef7747
--- /dev/null
+++ b/llvm/test/Transforms/JumpThreading/2008-11-28-InfLoop.ll
@@ -0,0 +1,17 @@
+; RUN: llvm-as < %s | opt -jump-threading | llvm-dis
+
+target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128"
+target triple = "i386-apple-darwin9.5"
+	%struct.decContext = type { i32 }
+	%struct.decNumber = type { i32, i32 }
+
+define i32 @decNumberPower(%struct.decNumber* %res, %struct.decNumber* %lhs, %struct.decNumber* %rhs, %struct.decContext* %set) nounwind {
+entry:
+	br i1 true, label %decDivideOp.exit, label %bb7.i
+
+bb7.i:		; preds = %bb7.i, %entry
+	br label %bb7.i
+
+decDivideOp.exit:		; preds = %entry
+	ret i32 undef
+}