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1.8.3.1
gecode
int
div.hpp
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/* -*- mode: C++; c-basic-offset: 2; indent-tabs-mode: nil -*- */
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/*
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* Main authors:
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* Christian Schulte <schulte@gecode.org>
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*
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* Copyright:
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* Christian Schulte, 2013
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*
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* Last modified:
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* $Date: 2013-02-19 15:42:19 +0100 (Tue, 19 Feb 2013) $ by $Author: schulte $
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* $Revision: 13315 $
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*
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* This file is part of Gecode, the generic constraint
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* development environment:
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* http://www.gecode.org
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*
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* Permission is hereby granted, free of charge, to any person obtaining
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* a copy of this software and associated documentation files (the
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* "Software"), to deal in the Software without restriction, including
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* without limitation the rights to use, copy, modify, merge, publish,
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* distribute, sublicense, and/or sell copies of the Software, and to
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* permit persons to whom the Software is furnished to do so, subject to
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* the following conditions:
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*
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* The above copyright notice and this permission notice shall be
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* included in all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
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* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
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* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
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* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
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* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
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* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
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*
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*/
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namespace
Gecode {
namespace
Int {
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template
<
class
IntType>
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forceinline
IntType
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ceil_div_pp
(
IntType
x
,
IntType
y) {
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assert((x >= 0) && (y >= 0));
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/*
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* This is smarter than it looks: for many cpus, % and / are
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* implemented by the same instruction and an optimizing compiler
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* will generate the instruction only once.
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*/
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return
((x % y) == 0) ? x/y : (x/y + 1);
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}
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template
<
class
IntType>
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forceinline
IntType
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floor_div_pp
(
IntType
x
,
IntType
y) {
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assert((x >= 0) && (y >= 0));
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return
x / y;
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}
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template
<
class
IntType>
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forceinline
IntType
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ceil_div_px
(
IntType
x
,
IntType
y) {
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assert(x >= 0);
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return
(y >= 0) ?
ceil_div_pp
(x,y) : -
floor_div_pp
(x,-y);
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}
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template
<
class
IntType>
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forceinline
IntType
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floor_div_px
(
IntType
x
,
IntType
y) {
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assert(x >= 0);
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return
(y >= 0) ?
floor_div_pp
(x,y) : -
ceil_div_pp
(x,-y);
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}
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template
<
class
IntType>
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forceinline
IntType
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ceil_div_xp
(
IntType
x
,
IntType
y) {
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assert(y >= 0);
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return
(x >= 0) ?
ceil_div_pp
(x,y) : -
floor_div_pp
(-x,y);
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}
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template
<
class
IntType>
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forceinline
IntType
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floor_div_xp
(
IntType
x
,
IntType
y) {
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assert(y >= 0);
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return
(x >= 0) ?
floor_div_pp
(x,y) : -
ceil_div_pp
(-x,y);
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}
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template
<
class
IntType>
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forceinline
IntType
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ceil_div_xx
(
IntType
x
,
IntType
y) {
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return
(x >= 0) ?
ceil_div_px
(x,y) : -
floor_div_px
(-x,y);
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}
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template
<
class
IntType>
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forceinline
IntType
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floor_div_xx
(
IntType
x
,
IntType
y) {
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return
(x >= 0) ?
floor_div_px
(x,y) : -
ceil_div_px
(-x,y);
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}
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}}
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// STATISTICS: int-prop
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