re PR tree-optimization/64183 (Complete unroll doesn't happen for a while-loop)

	PR tree-optimization/64183
	* c-gimplify.c (c_gimplify_expr): Don't convert the RHS of a
	shift-expression if it is integer_type_node.  Use types_compatible_p.

	* gcc.dg/tree-ssa/pr64183.c: New test.

From-SVN: r218447

gcc/c-family/ChangeLog

+2014-12-06  Marek Polacek  <polacek@redhat.com>
+
+	PR tree-optimization/64183
+	* c-gimplify.c (c_gimplify_expr): Don't convert the RHS of a
+	shift-expression if it is integer_type_node.  Use types_compatible_p.
+
 2014-11-29  Jakub Jelinek  <jakub@redhat.com>
 
 	* c-common.c (convert_vector_to_pointer_for_subscript): Remove NULL

gcc/c-family/c-gimplify.c

@@ -255,7 +255,10 @@ c_gimplify_expr (tree *expr_p, gimple_seq *pre_p ATTRIBUTE_UNUSED,
 	   type demotion/promotion pass.  */
 	tree *op1_p = &TREE_OPERAND (*expr_p, 1);
 	if (TREE_CODE (TREE_TYPE (*op1_p)) != VECTOR_TYPE
-	    && TYPE_MAIN_VARIANT (TREE_TYPE (*op1_p)) != unsigned_type_node)
+	    && !types_compatible_p (TYPE_MAIN_VARIANT (TREE_TYPE (*op1_p)),
+				    unsigned_type_node)
+	    && !types_compatible_p (TYPE_MAIN_VARIANT (TREE_TYPE (*op1_p)),
+				    integer_type_node))
 	  *op1_p = convert (unsigned_type_node, *op1_p);
 	break;
       }

gcc/testsuite/ChangeLog

+2014-12-06  Marek Polacek  <polacek@redhat.com>
+
+	PR tree-optimization/64183
+	* gcc.dg/tree-ssa/pr64183.c: New test.
+
 2014-12-06  H.J. Lu  <hongjiu.lu@intel.com>
 
 	PR target/64200

gcc/testsuite/gcc.dg/tree-ssa/pr64183.c

+/* { dg-do compile } */
+/* { dg-options "-O3 -fdump-tree-cunroll-details" } */
+
+int bits;
+unsigned int size;
+int max_code;
+
+void
+test ()
+{
+ int code = 0;
+
+ while (code < max_code)
+   code |= ((unsigned int) (size >> (--bits)));
+
+ while (bits < (unsigned int)25)
+   bits += 8;
+}
+
+/* { dg-final { scan-tree-dump "Loop 2 iterates at most 4 times" "cunroll"} } */
+/* { dg-final { cleanup-tree-dump "cunroll" } } */