ISD::UNDEF should be expanded recursively / iteratively.

llvm-svn: 52508
diff --git a/llvm/test/CodeGen/PowerPC/2008-06-19-LegalizerCrash.ll b/llvm/test/CodeGen/PowerPC/2008-06-19-LegalizerCrash.ll
new file mode 100644
index 0000000..d337e37
--- /dev/null
+++ b/llvm/test/CodeGen/PowerPC/2008-06-19-LegalizerCrash.ll
@@ -0,0 +1,6 @@
+; RUN: llvm-as < %s | llc -march=ppc32
+
+define void @t() nounwind {
+	call void null( ppc_fp128 undef )
+	unreachable
+}