re PR target/66648 (incorrect memcpy expansion with unrolled_loop strategy at -O2)

	PR target/66648
	* config/i386/i386.c (ix86_expand_set_or_movmem): Emit main loop
	execution guard when min_size is less than size_needed.

testsuite/ChangeLog:

	PR target/66648
	* gcc.target/i386/pr66648.c: New test.

From-SVN: r226212

2 files changed, 38 insertions, 0 deletions

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index f832fb1..55e4cb0 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2015-07-25  Uros Bizjak  <ubizjak@gmail.com>
+
+	PR target/66648
+	* gcc.target/i386/pr66648.c: New test.
+
 2015-07-25  Tom de Vries  <tom@codesourcery.com>
 
 	* gcc.dg/graphite/graphite.exp: Include uns-*.c files in
diff --git a/gcc/testsuite/gcc.target/pr66648.c b/gcc/testsuite/gcc.target/pr66648.c
new file mode 100644
index 0000000..88c126f
--- /dev/null
+++ b/gcc/testsuite/gcc.target/pr66648.c
@@ -0,0 +1,33 @@
+/* { dg-do run } */
+/* { dg-options "-O2 -mstringop-strategy=unrolled_loop -mtune=nocona" } */
+
+#define PATTERN 0xdeadbeef
+#define SIZE    32
+
+struct S { int i; char str[SIZE]; int j; };
+
+void __attribute__((noclone, noinline))
+my_memcpy (char *, const char *, unsigned int);
+
+void
+my_memcpy (char *dst, const char *src, unsigned int len)
+{
+  if (len < 8)
+    __builtin_abort ();
+
+  __builtin_memcpy (dst, src, len);
+}
+
+int
+main (void)
+{
+  const char str[SIZE]= "1234567890123456789012345678901";
+  struct S *s = __builtin_malloc (sizeof (struct S));
+
+  s->j = PATTERN;
+  my_memcpy (s->str, str, SIZE);
+  if (s->j != PATTERN)
+    __builtin_abort ();
+
+  return 0;
+}