--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/CodeGen/AArch64/bitfield-insert-0.ll	Thu Dec 12 13:56:28 2013 +0900
@@ -0,0 +1,19 @@
+; RUN: llc -mtriple=aarch64-none-linux-gnu -filetype=obj < %s | llvm-objdump -disassemble - | FileCheck %s
+
+; The encoding of lsb -> immr in the CGed bitfield instructions was wrong at one
+; point, in the edge case where lsb = 0. Just make sure.
+
+define void @test_bfi0(i32* %existing, i32* %new) {
+; CHECK: bfxil {{w[0-9]+}}, {{w[0-9]+}}, #0, #18
+
+  %oldval = load volatile i32* %existing
+  %oldval_keep = and i32 %oldval, 4294705152 ; 0xfffc_0000
+
+  %newval = load volatile i32* %new
+  %newval_masked = and i32 %newval, 262143 ; = 0x0003_ffff
+
+  %combined = or i32 %newval_masked, %oldval_keep
+  store volatile i32 %combined, i32* %existing
+
+  ret void
+}