[ARM] Add earlyclobber constraint to pre/post-indexed ARM STR instructions.

[oota-llvm.git] / test / CodeGen / ARM / 2014-07-18-earlyclobber-str-post.ll

diff --git a/test/CodeGen/ARM/2014-07-18-earlyclobber-str-post.ll b/test/CodeGen/ARM/2014-07-18-earlyclobber-str-post.ll
new file mode 100644 (file)
index 0000000..9ea762a
--- /dev/null
+++ b/test/CodeGen/ARM/2014-07-18-earlyclobber-str-post.ll
@@ -0,0 +1,13 @@
+; RUN: llc -mtriple=armv7-linux-gnueabihf %s -o - | FileCheck %s
+
+; Check that we don't create an unpredictable STR instruction,
+; e.g. str r0, [r0], #4
+
+define i32* @earlyclobber-str-post(i32* %addr) nounwind {
+; CHECK: earlyclobber-str-post
+; CHECK-NOT: str r[[REG:[0-9]+]], [r[[REG]]], #4
+  %val = ptrtoint i32* %addr to i32
+  store i32 %val, i32* %addr
+  %new = getelementptr i32* %addr, i32 1
+  ret i32* %new
+}