(note_mem_written): Varying structure memory access with

AND address can alias scalars.

From-SVN: r12417

diff --git a/gcc/cse.c b/gcc/cse.c
index e2baf7d..ba816d7 100644 (file)
--- a/gcc/cse.c
+++ b/gcc/cse.c
@@ -7583,10 +7583,15 @@ note_mem_written (written, writes_ptr)
             and that's just as good as a structure element
             in implying that we need not invalidate scalar variables.
             However, we must allow QImode aliasing of scalars, because the
-            ANSI C standard allows character pointers to alias anything.  */
+            ANSI C standard allows character pointers to alias anything.
+            We must also allow AND addresses, because they may generate
+            accesses outside the object being referenced.  This is used to
+            generate aligned addresses from unaligned addresses, for instance,
+            the alpha storeqi_unaligned pattern.  */
          if (! ((MEM_IN_STRUCT_P (written)
                  || GET_CODE (XEXP (written, 0)) == PLUS)
-                && GET_MODE (written) != QImode))
+                && GET_MODE (written) != QImode
+                && GET_CODE (XEXP (written, 0)) != AND))
            writes_ptr->all = 1;
          writes_ptr->nonscalar = 1;
        }