match.pd: New simplification patterns.

* match.pd: New simplification patterns.
	(x + (x & 1))  -> ((x + 1) & ~1)
	(x & ~(x & y)) -> ((x & ~y))
	(x | ~(x | y)) -> ((x | ~y))

	* gcc.dg/20150120-1.c: New test.
	* gcc.dg/20150120-2.c: New test.
	* gcc.dg/20150120-3.c: New test.

From-SVN: r222697

gcc/ChangeLog

@@ -1,3 +1,10 @@
+2015-05-01  Rasmus Villemoes  <rv@rasmusvillemoes.dk>
+
+	* match.pd: New simplification patterns.
+	(x + (x & 1))  -> ((x + 1) & ~1)
+	(x & ~(x & y)) -> ((x & ~y))
+	(x | ~(x | y)) -> ((x | ~y))
+
 2015-05-01  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>
 
 	* target.def (attribute_table): Mention that struct attribute_spec

gcc/match.pd

@@ -255,6 +255,20 @@ along with GCC; see the file COPYING3.  If not see
   (bitop @0 @0)
   (non_lvalue @0)))
 
+/* x + (x & 1) -> (x + 1) & ~1 */
+(simplify
+ (plus:c @0 (bit_and@2 @0 integer_onep@1))
+ (if (TREE_CODE (@2) != SSA_NAME || has_single_use (@2))
+  (bit_and (plus @0 @1) (bit_not @1))))
+
+/* x & ~(x & y) -> x & ~y */
+/* x | ~(x | y) -> x | ~y  */
+(for bitop (bit_and bit_ior)
+  (simplify
+    (bitop:c @0 (bit_not (bitop:c@2 @0 @1)))
+      (if (TREE_CODE (@2) != SSA_NAME || has_single_use (@2))
+	(bitop @0 (bit_not @1)))))
+
 (simplify
  (abs (negate @0))
  (abs @0))

gcc/testsuite/ChangeLog

@@ -1,3 +1,9 @@
+2015-05-01  Rasmus Villemoes  <rv@rasmusvillemoes.dk>
+
+	* gcc.dg/20150120-1.c: New test.
+	* gcc.dg/20150120-2.c: New test.
+	* gcc.dg/20150120-3.c: New test.
+
 2015-05-01  David Edelsohn  <dje.gcc@gmail.com>
 
 	* gcc.dg/debug/pr65771.c: Add "dg-add-options tls".

gcc/testsuite/gcc.dg/20150120-1.c

@@ -0,0 +1,51 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-original" } */
+
+/* x + (x & 1) -> (x + 1) & ~1 */
+int
+fn1 (int x)
+{
+	return x + (x & 1);
+}
+int
+fn2 (int x)
+{
+	return (x & 1) + x;
+}
+int
+fn3 (int x)
+{
+	return x + (1 & x);
+}
+int
+fn4 (int x)
+{
+	return (1 & x) + x;
+}
+unsigned int
+fn5 (unsigned int x)
+{
+	return x + (x & 1);
+}
+unsigned int
+fn6 (unsigned int x)
+{
+	return (x & 1) + x;
+}
+unsigned int
+fn7 (unsigned int x)
+{
+	return x + (x % 2);
+}
+unsigned int
+fn8 (unsigned int x)
+{
+	return (x % 2) + x;
+}
+unsigned int
+fn9 (unsigned int x)
+{
+	return (1LL & x) + x;
+}
+
+/* { dg-final { scan-tree-dump-times "x \\+ 1" 9 "original" } } */

gcc/testsuite/gcc.dg/20150120-2.c

@@ -0,0 +1,32 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-original" } */
+
+/* x & ~(x & y) -> x & ~y */
+int fn1 (int x, int y)
+{
+	return x & ~(x & y);
+}
+int fn2 (int x, int y)
+{
+	return ~(x & y) & x;
+}
+int fn3 (int x, int y)
+{
+	return x & ~(y & x);
+}
+int fn4 (int x, int y)
+{
+	return ~(y & x) & x;
+}
+int fn5 (int z)
+{
+	return z & ~(z & 3);
+}
+int fn6 (int z)
+{
+	return ~(z & 3) & z;
+}
+
+
+/* { dg-final { scan-tree-dump-times "~y & x" 4 "original" } } */
+/* { dg-final { scan-tree-dump-times "z & -4" 2 "original" } } */

gcc/testsuite/gcc.dg/20150120-3.c

@@ -0,0 +1,32 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-original" } */
+
+/* x | ~(x | y) -> x | ~y */
+int fn1 (int x, int y)
+{
+	return x | ~(x | y);
+}
+int fn2 (int x, int y)
+{
+	return ~(x | y) | x;
+}
+int fn3 (int x, int y)
+{
+	return x | ~(y | x);
+}
+int fn4 (int x, int y)
+{
+	return ~(y | x) | x;
+}
+int fn5 (int z)
+{
+	return z | ~(z | 3);
+}
+int fn6 (int z)
+{
+	return ~(z | 3) | z;
+}
+
+
+/* { dg-final { scan-tree-dump-times "~y \\| x" 4 "original" } } */
+/* { dg-final { scan-tree-dump-times "z \\| -4" 2 "original" } } */