1 files changed, 40 insertions, 0 deletions
diff --git a/gcc/testsuite/gcc.dg/torture/parm-coalesce.c b/gcc/testsuite/gcc.dg/torture/parm-coalesce.c
new file mode 100644
index 00000000000..dbd81c1ba21
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/parm-coalesce.c
@@ -0,0 +1,40 @@
+/* { dg-do run } */
+
+#include <stdlib.h>
+
+/* Make sure we don't coalesce both incoming parms, one whose incoming
+   value is unused, to the same location, so as to overwrite one of
+   them with the incoming value of the other.  */
+
+int __attribute__((noinline, noclone))
+foo (int i, int j)
+{
+  j = i; /* The incoming value for J is unused.  */
+  i = 2;
+  if (j)
+    j++;
+  j += i + 1;
+  return j;
+}
+
+/* Same as foo, but with swapped parameters.  */
+int __attribute__((noinline, noclone))
+bar (int j, int i)
+{
+  j = i; /* The incoming value for J is unused.  */
+  i = 2;
+  if (j)
+    j++;
+  j += i + 1;
+  return j;
+}
+
+int
+main (void)
+{
+  if (foo (0, 1) != 3)
+    abort ();
+  if (bar (1, 0) != 3)
+    abort ();
+  return 0;
+}