Re: Add VIEW_CONVERT_EXPR to operand_equal_p

[Jan Hubicka <hubicka@ucw.cz>]

Hi,
this is patch that reverts the TYPE_MODE mismatch related changes and
adds test to type checker that TYPE_MODE always match with TYPE_CANONICAL.
I have bootstrapped/regtested x86_64-linux, but unfrtunately the regtesting
had some unrelated noise (spawn failures). I am re-testing. I am on a trip
and will likely only access interenet again from Des Moines tonight.

Honza

	* tree.c (verify_type): Verify that TYPE_MODE match
	between TYPE_CANONICAL and type.
	* expr.c (store_expr_with_bounds): Revert my previous change.
	* expmed.c (store_bit_field_1): Revert prevoius change.
	* gimple-expr.c (useless_type_conversion_p): Require TYPE_MODE
	to match for complete types.

Index: tree.c
===================================================================
--- tree.c	(revision 228933)
+++ tree.c	(working copy)
@@ -13344,6 +13344,14 @@ verify_type (const_tree t)
       error_found = true;
     }
 
+  if (COMPLETE_TYPE_P (t) && TYPE_CANONICAL (t)
+      && TYPE_MODE (t) != TYPE_MODE (TYPE_CANONICAL (t)))
+    {
+      error ("TYPE_MODE of TYPE_CANONICAL is not compatible");
+      debug_tree (ct);
+      error_found = true;
+    }
+
 
   /* Check various uses of TYPE_MINVAL.  */
   if (RECORD_OR_UNION_TYPE_P (t))
Index: expr.c
===================================================================
--- expr.c	(revision 228933)
+++ expr.c	(working copy)
@@ -5425,14 +5425,6 @@ store_expr_with_bounds (tree exp, rtx ta
     temp = convert_modes (GET_MODE (target), TYPE_MODE (TREE_TYPE (exp)),
 			  temp, TYPE_UNSIGNED (TREE_TYPE (exp)));
 
-  /* We allow move between structures of same size but different mode.
-     If source is in memory and the mode differs, simply change the memory.  */
-  if (GET_MODE (temp) == BLKmode && GET_MODE (target) != BLKmode)
-    {
-      gcc_assert (MEM_P (temp));
-      temp = adjust_address_nv (temp, GET_MODE (target), 0);
-    }
-
   /* If value was not generated in the target, store it there.
      Convert the value to TARGET's type first if necessary and emit the
      pending incrementations that have been queued when expanding EXP.
Index: expmed.c
===================================================================
--- expmed.c	(revision 228933)
+++ expmed.c	(working copy)
@@ -757,14 +757,6 @@ store_bit_field_1 (rtx str_rtx, unsigned
       }
   }
 
-  /* We allow move between structures of same size but different mode.
-     If source is in memory and the mode differs, simply change the memory.  */
-  if (GET_MODE (value) == BLKmode && GET_MODE (op0) != BLKmode)
-    {
-      gcc_assert (MEM_P (value));
-      value = adjust_address_nv (value, GET_MODE (op0), 0);
-    }
-
   /* Storing an lsb-aligned field in a register
      can be done with a movstrict instruction.  */
 
Index: gimple-expr.c
===================================================================
--- gimple-expr.c	(revision 228933)
+++ gimple-expr.c	(working copy)
@@ -88,9 +88,10 @@ useless_type_conversion_p (tree outer_ty
     return true;
 
   /* Changes in machine mode are never useless conversions unless we
-     deal with aggregate types in which case we defer to later checks.  */
+     deal with complete aggregate types in which case we defer to later
+     checks.  */
   if (TYPE_MODE (inner_type) != TYPE_MODE (outer_type)
-      && !AGGREGATE_TYPE_P (inner_type))
+      && (!AGGREGATE_TYPE_P (inner_type) || COMPLETE_TYPE_P (outer_type)))
     return false;
 
   /* If both the inner and outer types are integral types, then the