re PR tree-optimization/18184 (Tree optimizers ignore pointer modes)

ChangeLog:

	PR tree-optimization/18184
	* c-typeck.c (comptypes): Do not treat pointers of different
	modes or alias-all flags as equivalent.
	* tree-ssa.c (tree_ssa_useless_type_conversion_1): Likewise.

cp/ChangeLog:

	PR tree-optimization/18184
	* cp-objcp-common.c (cxx_types_compatible_p): Do not treat pointers
	of different modes or alias-all flags as equivalent.
	* typeck.c (comptypes): Likewise.

From-SVN: r90078

gcc/ChangeLog

+2004-11-04  Ulrich Weigand  <uweigand@de.ibm.com>
+
+	PR tree-optimization/18184
+	* c-typeck.c (comptypes): Do not treat pointers of different
+	modes or alias-all flags as equivalent.
+	* tree-ssa.c (tree_ssa_useless_type_conversion_1): Likewise.
+
 2004-11-04  Joseph S. Myers  <joseph@codesourcery.com>
 
 	* doc/gty.texi, doc/makefile.texi, doc/sourcebuild.texi: Don't

gcc/c-typeck.c

@@ -659,6 +659,10 @@ comptypes (tree type1, tree type2)
 	   protocol qualifiers may be involved.  */
       if (c_dialect_objc () && (val = objc_comptypes (t1, t2, 0)) >= 0)
 	break;
+      /* Do not remove mode or aliasing information.  */
+      if (TYPE_MODE (t1) != TYPE_MODE (t2)
+	  || TYPE_REF_CAN_ALIAS_ALL (t1) != TYPE_REF_CAN_ALIAS_ALL (t2))
+	break;
       val = (TREE_TYPE (t1) == TREE_TYPE (t2)
 	     ? 1 : comptypes (TREE_TYPE (t1), TREE_TYPE (t2)));
       break;

gcc/cp/ChangeLog

+2004-11-04  Ulrich Weigand  <uweigand@de.ibm.com>
+	
+	PR tree-optimization/18184
+	* cp-objcp-common.c (cxx_types_compatible_p): Do not treat pointers
+	of different modes or alias-all flags as equivalent.
+	* typeck.c (comptypes): Likewise.
+
 2004-11-04  Giovanni Bajo  <giovannibajo@gcc.gnu.org>
 
 	DR 49, 100

gcc/cp/cp-objcp-common.c

@@ -162,6 +162,8 @@ cxx_types_compatible_p (tree x, tree y)
      interchangeable.  FIXME should we try to replace all references with
      pointers?  */
   if (POINTER_TYPE_P (x) && POINTER_TYPE_P (y)
+      && TYPE_MODE (x) == TYPE_MODE (y)
+      && TYPE_REF_CAN_ALIAS_ALL (x) == TYPE_REF_CAN_ALIAS_ALL (y)
       && same_type_p (TREE_TYPE (x), TREE_TYPE (y)))
     return 1;
 

gcc/cp/typeck.c

@@ -1030,11 +1030,13 @@ comptypes (tree t1, tree t2, int strict)
       if (!comptypes (TYPE_OFFSET_BASETYPE (t1), TYPE_OFFSET_BASETYPE (t2),
 		      strict & ~COMPARE_REDECLARATION))
 	return false;
-      /* Fall through.  */
+      return same_type_p (TREE_TYPE (t1), TREE_TYPE (t2));
 
     case POINTER_TYPE:
     case REFERENCE_TYPE:
-      return same_type_p (TREE_TYPE (t1), TREE_TYPE (t2));
+      return TYPE_MODE (t1) == TYPE_MODE (t2)
+	     && TYPE_REF_CAN_ALIAS_ALL (t1) == TYPE_REF_CAN_ALIAS_ALL (t2)
+	     && same_type_p (TREE_TYPE (t1), TREE_TYPE (t2));
 
     case METHOD_TYPE:
     case FUNCTION_TYPE:

gcc/tree-ssa.c

@@ -834,6 +834,9 @@ tree_ssa_useless_type_conversion_1 (tree outer_type, tree inner_type)
      implement the ABI.  */
   else if (POINTER_TYPE_P (inner_type)
            && POINTER_TYPE_P (outer_type)
+	   && TYPE_MODE (inner_type) == TYPE_MODE (outer_type)
+	   && TYPE_REF_CAN_ALIAS_ALL (inner_type)
+	      == TYPE_REF_CAN_ALIAS_ALL (outer_type)
 	   && TREE_CODE (TREE_TYPE (outer_type)) == VOID_TYPE)
     return true;
 
@@ -841,6 +844,9 @@ tree_ssa_useless_type_conversion_1 (tree outer_type, tree inner_type)
      so strip conversions that just switch between them.  */
   else if (POINTER_TYPE_P (inner_type)
            && POINTER_TYPE_P (outer_type)
+	   && TYPE_MODE (inner_type) == TYPE_MODE (outer_type)
+	   && TYPE_REF_CAN_ALIAS_ALL (inner_type)
+	      == TYPE_REF_CAN_ALIAS_ALL (outer_type)
            && lang_hooks.types_compatible_p (TREE_TYPE (inner_type),
 					     TREE_TYPE (outer_type)))
     return true;