diff --git a/llvm/test/Regression/Transforms/LoopPreheaders/2003-04-25-AssertFail.ll b/llvm/test/Regression/Transforms/LoopPreheaders/2003-04-25-AssertFail.ll
new file mode 100644
index 000000000000..968c34fd17d9
--- /dev/null
+++ b/llvm/test/Regression/Transforms/LoopPreheaders/2003-04-25-AssertFail.ll
@@ -0,0 +1,22 @@
+; RUN: as < %s | opt -preheaders
+
+implementation   ; Functions:
+
+int %yylex() {		; No predecessors!
+	br label %loopentry.0
+
+loopentry.0:		; preds = %0, %yy_find_action, %else.4
+	br label %loopexit.2
+
+loopexit.2:		; preds = %loopentry.0, %else.4, %loopexit.2
+	br bool false, label %loopexit.2, label %else.4
+
+yy_find_action:		; preds = %loopexit.2, %else.4
+	br label %else.4
+
+else.4:		; preds = %yy_find_action
+	switch uint 0, label %loopexit.2 [
+		 uint 2, label %yy_find_action
+		 uint 0, label %loopentry.0
+	]
+}
diff --git a/llvm/test/Regression/Transforms/LoopSimplify/2003-04-25-AssertFail.ll b/llvm/test/Regression/Transforms/LoopSimplify/2003-04-25-AssertFail.ll
new file mode 100644
index 000000000000..968c34fd17d9
--- /dev/null
+++ b/llvm/test/Regression/Transforms/LoopSimplify/2003-04-25-AssertFail.ll
@@ -0,0 +1,22 @@
+; RUN: as < %s | opt -preheaders
+
+implementation   ; Functions:
+
+int %yylex() {		; No predecessors!
+	br label %loopentry.0
+
+loopentry.0:		; preds = %0, %yy_find_action, %else.4
+	br label %loopexit.2
+
+loopexit.2:		; preds = %loopentry.0, %else.4, %loopexit.2
+	br bool false, label %loopexit.2, label %else.4
+
+yy_find_action:		; preds = %loopexit.2, %else.4
+	br label %else.4
+
+else.4:		; preds = %yy_find_action
+	switch uint 0, label %loopexit.2 [
+		 uint 2, label %yy_find_action
+		 uint 0, label %loopentry.0
+	]
+}