re PR tree-optimization/54976 (FAIL: gcc.dg/torture/pr47975.c (internal compiler error))

2012-10-19  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/54976
	* tree-vect-stmts.c (get_vectype_for_scalar_type_and_size):
	Robustify against odd inner_mode inputs.

From-SVN: r192611

gcc/ChangeLog

+2012-10-19  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/54976
+	* tree-vect-stmts.c (get_vectype_for_scalar_type_and_size):
+	Robustify against odd inner_mode inputs.
+
 2012-10-19  Zhenqiang Chen <zhenqiang.chen@linaro.org>
 
 	PR target/54892

gcc/tree-vect-stmts.c

@@ -6082,16 +6082,21 @@ get_vectype_for_scalar_type_and_size (tree scalar_type, unsigned size)
      When the component mode passes the above test simply use a type
      corresponding to that mode.  The theory is that any use that
      would cause problems with this will disable vectorization anyway.  */
-  if (!SCALAR_FLOAT_TYPE_P (scalar_type)
-      && !INTEGRAL_TYPE_P (scalar_type)
-      && !POINTER_TYPE_P (scalar_type))
+  else if (!SCALAR_FLOAT_TYPE_P (scalar_type)
+	   && !INTEGRAL_TYPE_P (scalar_type)
+	   && !POINTER_TYPE_P (scalar_type))
     scalar_type = lang_hooks.types.type_for_mode (inner_mode, 1);
 
   /* We can't build a vector type of elements with alignment bigger than
      their size.  */
-  if (nbytes < TYPE_ALIGN_UNIT (scalar_type))
+  else if (nbytes < TYPE_ALIGN_UNIT (scalar_type))
     scalar_type = lang_hooks.types.type_for_mode (inner_mode, 1);
 
+  /* If we felt back to using the mode fail if there was
+     no scalar type for it.  */
+  if (scalar_type == NULL_TREE)
+    return NULL_TREE;
+
   /* If no size was supplied use the mode the target prefers.   Otherwise
      lookup a vector mode of the specified size.  */
   if (size == 0)