expr.c (expand_expr, [...]): Refine test for when to copy misaligned data.

	* expr.c (expand_expr, case ADDR_EXPR): Refine test for when to
	copy misaligned data.
	* varasm.c (assemble_variable): Set alignment into MEM when changed.

From-SVN: r47089

gcc/ChangeLog

+Fri Nov 16 09:06:25 2001  Richard Kenner  <kenner@vlsi1.ultra.nyu.edu>
+
+	* expr.c (expand_expr, case ADDR_EXPR): Refine test for when to
+	copy misaligned data.
+	* varasm.c (assemble_variable): Set alignment into MEM when changed.
+
 2001-11-16  Graham Stott  <grahams@redhat.com>
 
 	* optabs.c (prepare_cmp_insn): Correct lossage in last change fix

gcc/expr.c

@@ -8649,11 +8649,19 @@ expand_expr (exp, target, tmode, modifier)
 	      return op0;
 	    }
 
-	  /* If OP0 is not aligned as least as much as the type requires,
-	     we need to make a temporary, copy OP0 to it, and take the
-	     address of the temporary.  */
-	  if (GET_MODE (op0) == BLKmode
-	      && expr_align (TREE_OPERAND (exp, 0)) > MEM_ALIGN (op0))
+	  /* If OP0 is not aligned as least as much as the type requires, we
+	     need to make a temporary, copy OP0 to it, and take the address of
+	     the temporary.  We want to use the alignment of the type, not of
+	     the operand.  Note that this is incorrect for FUNCTION_TYPE, but
+	     the test for BLKmode means that can't happen.  The test for
+	     BLKmode is because we never make mis-aligned MEMs with
+	     non-BLKmode.
+
+	     We don't need to do this at all if the machine doesn't have
+	     strict alignment.  */
+	  if (STRICT_ALIGNMENT && GET_MODE (op0) == BLKmode
+	      && (TYPE_ALIGN (TREE_TYPE (TREE_OPERAND (exp, 0)))
+		  > MEM_ALIGN (op0)))
 	    {
 	      tree inner_type = TREE_TYPE (TREE_OPERAND (exp, 0));
 	      rtx new

gcc/varasm.c

@@ -1615,6 +1615,7 @@ assemble_variable (decl, top_level, at_end, dont_output_data)
   /* Reset the alignment in case we have made it tighter, so we can benefit
      from it in get_pointer_alignment.  */
   DECL_ALIGN (decl) = align;
+  set_mem_align (decl_rtl, align);
 
   /* Handle uninitialized definitions.  */