tree-ssa-loop-niter.c (simplify_using_initial_conditions): Break loop if EXPR is…

tree-ssa-loop-niter.c (simplify_using_initial_conditions): Break loop if EXPR is simplified to const value.


	* tree-ssa-loop-niter.c (simplify_using_initial_conditions): Break
	loop if EXPR is simplified to const value.

From-SVN: r227055

gcc/ChangeLog

+2015-08-21  Bin Cheng  <bin.cheng@arm.com>
+
+	* tree-ssa-loop-niter.c (simplify_using_initial_conditions): Break
+	loop if EXPR is simplified to const value.
+
 2015-08-21  Yury Gribov  <y.gribov@samsung.com>
 
 	* sanitizer.def (BUILT_IN_UBSAN_HANDLE_NONNULL_ARG,

gcc/tree-ssa-loop-niter.c

@@ -2083,6 +2083,10 @@ simplify_using_initial_conditions (struct loop *loop, tree expr)
       if (e->flags & EDGE_FALSE_VALUE)
 	cond = invert_truthvalue (cond);
       expr = tree_simplify_using_condition (cond, expr);
+      /* Break if EXPR is simplified to const values.  */
+      if (expr && (integer_zerop (expr) || integer_nonzerop (expr)))
+	break;
+
       ++cnt;
     }