1 files changed, 20 insertions, 0 deletions
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr47286.c b/gcc/testsuite/gcc.dg/tree-ssa/pr47286.c
new file mode 100644
index 000000000..b03c59b83
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/pr47286.c
@@ -0,0 +1,20 @@
+/* { dg-do compile } */
+/* { dg-skip-if "" { ! { i?86-*-* x86_64-*-* } } { "*" } { "" } } */
+/* { dg-options "-O2 -fdump-tree-optimized" } */
+
+struct thread_info { int preempt_count; };
+static inline struct thread_info *current_thread_info(void)
+{
+  register struct thread_info *sp asm("esp");
+  return sp;
+}
+void testcase(void)
+{
+  current_thread_info()->preempt_count += 1;
+}
+
+/* We have to make sure that alias analysis treats sp as pointing
+   to globals and thus the store not optimized away.  */
+
+/* { dg-final { scan-tree-dump "->preempt_count =" "optimized" } } */
+/* { dg-final { cleanup-tree-dump "optimized" } } */