This is the mail archive of the gcc-patches@gcc.gnu.org mailing list for the GCC project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: [PATCH] Optimize more boolean functions


Hello all,

I have updated the testcase and run "make check" on Ubuntu x86_64.
All of them passed. (However the last part "do-check" couldn't be
run, probably due to a missing testsuite dependency?)

The match.pd is the same as the original patch, and I have
updated change-summaries and improved tests.

2018-08-21  MCC CS  <deswurstes@users.noreply.github.com>

	gcc/
	PR tree-optimization/87009
	* match.pd: Add boolean optimizations.

2018-08-21  MCC CS  <deswurstes@users.noreply.github.com>

	gcc/testsuite/
	PR tree-optimization/87009
	* gcc.dg/pr87009.c: New test.

Index: gcc/match.pd
===================================================================
--- gcc/match.pd	(revision 263646)
+++ gcc/match.pd	(working copy)
@@ -776,6 +776,11 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
  (bit_not (bit_and:cs (bit_not @0) @1))
  (bit_ior @0 (bit_not @1)))
 
+/* ~(~a | b)  -->  a & ~b  */
+(simplify
+ (bit_not (bit_ior:cs (bit_not @0) @1))
+ (bit_and @0 (bit_not @1)))
+
 /* Simplify (~X & Y) to X ^ Y if we know that (X & ~Y) is 0.  */
 #if GIMPLE
 (simplify
@@ -981,6 +986,16 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
  (bit_and:c (bit_ior:c @0 @1) (bit_xor:c @1 (bit_not @0)))
  (bit_and @0 @1))
 
+/* (~x | y) & (x | ~y) -> ~(x ^ y) */
+(simplify
+ (bit_and (bit_ior:c (bit_not @0) @1) (bit_ior:c @0 (bit_not @1)))
+ (bit_not (bit_xor @0 @1)))
+
+/* (~x | y) ^ (x | ~y) -> x ^ y */
+(simplify
+ (bit_xor (bit_ior:c (bit_not @0) @1) (bit_ior:c @0 (bit_not @1)))
+ (bit_xor @0 @1))
+
 /* ~x & ~y -> ~(x | y)
    ~x | ~y -> ~(x & y) */
 (for op (bit_and bit_ior)
Index: gcc/testsuite/gcc.dg/pr87009.c
===================================================================
--- gcc/testsuite/gcc.dg/pr87009.c	(nonexistent)
+++ gcc/testsuite/gcc.dg/pr87009.c	(working copy)
@@ -0,0 +1,23 @@
+/* { dg-do compile } */
+/* { dg-options "-O -fdump-tree-original" } */
+/* { dg-final { scan-tree-dump-times "return s \\^ x;" 4 "original" } } */
+
+int f1 (int x, int s)
+{
+  return ~(~(x|s)|x)|~(~(x|s)|s);
+}
+
+int f2 (int x, int s)
+{
+  return ~(~(~x&s)&~(x&~s));
+}
+
+int f3 (int x, int s)
+{
+  return ~((x|~s)&(~x|s));
+}
+
+int f4 (int x, int s)
+{
+  return (x|~s)^(~x|s);
+}


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]