[PPL-devel] [GIT] ppl/ppl(master): Optimized smod_2exp_signed_int.

[Abramo Bagnara]

Module: ppl/ppl
Branch: master
Commit: 21d120a07448821720acd415213f9b08a9a14338
URL:    http://www.cs.unipr.it/git/gitweb.cgi?p=ppl/ppl.git;a=commit;h=21d120a07448821720acd415213f9b08a9a14338

Author: Abramo Bagnara <abramo.bagnara at gmail.com>
Date:   Tue May  4 13:07:37 2010 +0200

Optimized smod_2exp_signed_int.

---

 src/checked_int.inlines.hh |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/checked_int.inlines.hh b/src/checked_int.inlines.hh
index 79985cd..6217dc7 100644
--- a/src/checked_int.inlines.hh
+++ b/src/checked_int.inlines.hh
@@ -1310,8 +1310,8 @@ smod_2exp_signed_int(Type& to, const Type x, unsigned int exp,
   if (exp >= sizeof(Type) * CHAR_BIT)
     to = x;
   else {
-    Type m = Type(1) << (exp - 1);
-    to = (x & (m - 1)) - (x & m);
+    Type m = -(Type(1) << (exp - 1));
+    to = (x + m) ^ m;
   }
   return V_EQ;
 }