match.pd ((x & y) ^ (x | y) -> x ^ y): New pattern.

	* match.pd ((x & y) ^ (x | y) -> x ^ y): New pattern.

	* gcc.dg/fold-xor-3.c: New test.

From-SVN: r224370

gcc/ChangeLog

 2015-06-11  Marek Polacek  <polacek@redhat.com>
 
+	* match.pd ((x & y) ^ (x | y) -> x ^ y): New pattern.
+
+2015-06-11  Marek Polacek  <polacek@redhat.com>
+
 	* match.pd: Use single_use throughout.
 
 2015-06-11  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>

gcc/match.pd

@@ -320,6 +320,12 @@ along with GCC; see the file COPYING3.  If not see
   (bitop:c (rbitop:c @0 @1) (bit_not@2 @0))
   (bitop @1 @2)))
 
+/* (x & y) ^ (x | y) -> x ^ y */
+(simplify
+ (bit_xor:c (bit_and@2 @0 @1) (bit_ior@3 @0 @1))
+  (if (single_use (@2) && single_use (@3))
+   (bit_xor @0 @1)))
+
 (simplify
  (abs (negate @0))
  (abs @0))

gcc/testsuite/ChangeLog

+2015-06-11  Marek Polacek  <polacek@redhat.com>
+
+	* gcc.dg/fold-xor-3.c: New test.
+
 2015-06-11  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>
 
 	* gcc.target/arm/short-it-ifcvt-1.c: New test.

gcc/testsuite/gcc.dg/fold-xor-3.c

+/* { dg-do compile } */
+/* { dg-options "-O -fdump-tree-cddce1" } */
+
+int
+fn1 (signed int x, signed int y)
+{
+  signed int tem1 = x & y;
+  signed int tem2 = x | y;
+  return tem1 ^ tem2;
+}
+
+unsigned int
+fn2 (unsigned int x, unsigned int y)
+{
+  unsigned int tem1 = x & y;
+  unsigned int tem2 = x | y;
+  return tem1 ^ tem2;
+}
+
+int
+fn3 (signed int x, signed int y)
+{
+  signed int tem1 = x & y;
+  signed int tem2 = x | y;
+  return tem2 ^ tem1;
+}
+
+unsigned int
+fn4 (unsigned int x, unsigned int y)
+{
+  unsigned int tem1 = x & y;
+  unsigned int tem2 = x | y;
+  return tem2 ^ tem1;
+}
+
+/* { dg-final { scan-tree-dump-not " & " "cddce1" } } */
+/* { dg-final { scan-tree-dump-not " \\| " "cddce1" } } */