re PR middle-end/25530 ((unsigned / 2)*2 is not changed into unsigned &~1)

PR middle-end/25530
2015-07-24  Naveen H.S  <Naveen.Hurugalawadi@caviumnetworks.com>

gcc/testsuite/ChangeLog:
	* gcc.dg/pr25530.c: New test.

gcc/ChangeLog:
	* match.pd (mult (trunc_div @0 integer_pow2p@1) @1) : New simplifier.

From-SVN: r226137

gcc/ChangeLog

 2015-07-24  Naveen H.S  <Naveen.Hurugalawadi@caviumnetworks.com>
 
+	PR middle-end/25530
+	* match.pd (mult (trunc_div @0 integer_pow2p@1) @1) : New simplifier.
+
+2015-07-24  Naveen H.S  <Naveen.Hurugalawadi@caviumnetworks.com>
+
          PR middle-end/25529
          * match.pd (trunc_div (mult @0 integer_pow2p@1) @1) : New simplifier.
 

gcc/match.pd

@@ -289,6 +289,12 @@ along with GCC; see the file COPYING3.  If not see
 		(type, wi::mask (TYPE_PRECISION (type) - wi::exact_log2 (@1),
 				 false, TYPE_PRECISION (type))); })))
 
+/* Simplify (unsigned t / 2) * 2 -> unsigned t & ~1.  */
+(simplify
+ (mult (trunc_div @0 integer_pow2p@1) @1)
+ (if (TYPE_UNSIGNED (TREE_TYPE (@0)))
+  (bit_and @0 (negate @1))))
+
 /* X % Y is smaller than Y.  */
 (for cmp (lt ge)
  (simplify

gcc/testsuite/ChangeLog

 2015-07-24  Naveen H.S  <Naveen.Hurugalawadi@caviumnetworks.com>
 
+	PR middle-end/25530
+	* gcc.dg/pr25530.c: New test.
+
+2015-07-24  Naveen H.S  <Naveen.Hurugalawadi@caviumnetworks.com>
+
 	PR middle-end/25529
 	* gcc.dg/pr25529.c: New test.
 

gcc/testsuite/gcc.dg/pr25530.c

+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-optimized" } */
+/* { dg-require-effective-target int32 } */
+
+int
+f (unsigned t)
+{
+  return (t / 2) * 2;
+}
+
+/* { dg-final { scan-tree-dump "\& -2" "optimized" } } */