From: Marek Polacek <polacek@redhat.com>
Date: Wed, 17 Dec 2014 11:48:33 +0000 (+0000)
Subject: re PR middle-end/63568 (Missed optimization (a & ~mask) | (b & mask) = a ^ ((a ^... 
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=f52baa7b6e1c62c273a2f1ffe045640ec90d6e6a;p=gcc.git

re PR middle-end/63568 (Missed optimization (a & ~mask) | (b & mask) = a ^ ((a ^ b) & mask))

	PR middle-end/63568
	* match.pd: Add (x & ~m) | (y & m) -> ((x ^ y) & m) ^ x pattern.

	* gcc.dg/pr63568.c: New test.

From-SVN: r218816
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 631d7268013..7b3c4aa6f75 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2014-12-17  Marek Polacek  <polacek@redhat.com>
+
+	PR middle-end/63568
+	* match.pd: Add (x & ~m) | (y & m) -> ((x ^ y) & m) ^ x pattern.
+
 2014-12-17  Jakub Jelinek  <jakub@redhat.com>
 
 	PR tree-optimization/64322
diff --git a/gcc/match.pd b/gcc/match.pd
index dbca99efb01..4d4bc9fac8e 100644
--- a/gcc/match.pd
+++ b/gcc/match.pd
@@ -382,6 +382,13 @@ along with GCC; see the file COPYING3.  If not see
   (bit_not (bit_not @0))
   @0)
 
+/* (x & ~m) | (y & m) -> ((x ^ y) & m) ^ x */
+(simplify
+  (bit_ior:c (bit_and:c@3 @0 (bit_not @2)) (bit_and:c@4 @1 @2))
+  (if ((TREE_CODE (@3) != SSA_NAME || has_single_use (@3))
+	&& (TREE_CODE (@4) != SSA_NAME || has_single_use (@4)))
+   (bit_xor (bit_and (bit_xor @0 @1) @2) @0)))
+
 
 /* Associate (p +p off1) +p off2 as (p +p (off1 + off2)).  */
 (simplify
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index fbafb565dac..7049260ccad 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2014-12-17  Marek Polacek  <polacek@redhat.com>
+
+	PR middle-end/63568
+	* gcc.dg/pr63568.c: New test.
+
 2014-12-17  Jakub Jelinek  <jakub@redhat.com>
 
 	PR tree-optimization/64322
diff --git a/gcc/testsuite/gcc.dg/pr63568.c b/gcc/testsuite/gcc.dg/pr63568.c
new file mode 100644
index 00000000000..fb42bea6fcf
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr63568.c
@@ -0,0 +1,54 @@
+/* PR middle-end/63568 */
+/* { dg-do compile } */
+/* { dg-options "-fdump-tree-original" } */
+
+int
+fn1 (int a, int b, int m)
+{
+  return (a & ~m) | (b & m);
+}
+
+int
+fn2 (int a, int b, int m)
+{
+  return (a & ~m) | (m & b);
+}
+
+int
+fn3 (int a, int b, int m)
+{
+  return (~m & a) | (m & b);
+}
+
+int
+fn4 (int a, int b, int m)
+{
+  return (~m & a) | (b & m);
+}
+
+int
+fn5 (int a, int b, int m)
+{
+  return (b & m) | (a & ~m);
+}
+
+int
+fn6 (int a, int b, int m)
+{
+  return (m & b) | (a & ~m);
+}
+
+int
+fn7 (int a, int b, int m)
+{
+  return (m & b) | (~m & a);
+}
+
+int
+fn8 (int a, int b, int m)
+{
+  return (b & m) | (~m & a);
+}
+
+/* { dg-final { scan-tree-dump-not " \\| " "original" } } */
+/* { dg-final { cleanup-tree-dump "original" } } */