===================================================================
@@ -25008,7 +25008,8 @@ ix86_expand_set_or_movmem (rtx dst, rtx src, rtx c
dst = change_address (dst, BLKmode, destreg);
set_mem_align (dst, desired_align * BITS_PER_UNIT);
epilogue_size_needed = 0;
- if (need_zero_guard && !min_size)
+ if (need_zero_guard
+ && min_size < (unsigned HOST_WIDE_INT) size_needed)
{
/* It is possible that we copied enough so the main loop will not
execute. */
@@ -25140,7 +25141,7 @@ ix86_expand_set_or_movmem (rtx dst, rtx src, rtx c
max_size -= align_bytes;
}
if (need_zero_guard
- && !min_size
+ && min_size < (unsigned HOST_WIDE_INT) size_needed
&& (count < (unsigned HOST_WIDE_INT) size_needed
|| (align_bytes == 0
&& count < ((unsigned HOST_WIDE_INT) size_needed
===================================================================
@@ -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;
+}