(note_addr_stored): A SET or CLOBBER of a BLKmode MEM means that all

memory is clobbered.

From-SVN: r7395

diff --git a/gcc/loop.c b/gcc/loop.c
index 17ef97a2776f196a55ba770b8a850ea83cc191b8..624329b1afbd838d3f21c0ce14b68e1d715c287f 100644 (file)
--- a/gcc/loop.c
+++ b/gcc/loop.c
@@ -2593,6 +2593,10 @@ note_addr_stored (x)
      This affects heuristics in strength_reduce.  */
   num_mem_sets++;
 
+  /* BLKmode MEM means all memory is clobbered.  */
+  if (GET_MODE (x) == BLKmode)
+    unknown_address_altered = 1;
+
   if (unknown_address_altered)
     return;
 
@@ -2601,10 +2605,9 @@ note_addr_stored (x)
        && MEM_IN_STRUCT_P (x) == MEM_IN_STRUCT_P (loop_store_mems[i]))
       {
        /* We are storing at the same address as previously noted.  Save the
-          wider reference, treating BLKmode as wider.  */
-       if (GET_MODE (x) == BLKmode
-           || (GET_MODE_SIZE (GET_MODE (x))
-               > GET_MODE_SIZE (GET_MODE (loop_store_mems[i]))))
+          wider reference.  */
+       if (GET_MODE_SIZE (GET_MODE (x))
+           > GET_MODE_SIZE (GET_MODE (loop_store_mems[i])))
          loop_store_mems[i] = x;
        break;
       }