axmol/js/spidermonkey-ios/include/ds/BitArray.h

92 lines
3.0 KiB
C++

/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
* vim: set ts=4 sw=4 et tw=99 ft=cpp:
*
* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is SpiderMonkey JavaScript engine.
*
* The Initial Developer of the Original Code is
* Mozilla Corporation.
* Portions created by the Initial Developer are Copyright (C) 2011
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Terrence Cole <terrence@mozilla.com>
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#ifndef BitArray_h__
#define BitArray_h__
#include "jstypes.h"
#include "js/TemplateLib.h"
namespace js {
template <size_t nbits>
class BitArray {
private:
uintptr_t map[nbits / JS_BITS_PER_WORD + (nbits % JS_BITS_PER_WORD == 0 ? 0 : 1)];
public:
void clear(bool value) {
if (value)
memset(map, 0xFF, sizeof(map));
else
memset(map, 0, sizeof(map));
}
inline bool get(size_t offset) const {
uintptr_t index, mask;
getMarkWordAndMask(offset, &index, &mask);
return map[index] & mask;
}
inline void set(size_t offset) {
uintptr_t index, mask;
getMarkWordAndMask(offset, &index, &mask);
map[index] |= mask;
}
inline void unset(size_t offset) {
uintptr_t index, mask;
getMarkWordAndMask(offset, &index, &mask);
map[index] &= ~mask;
}
private:
inline void getMarkWordAndMask(size_t offset,
uintptr_t *indexp, uintptr_t *maskp) const {
*indexp = offset >> tl::FloorLog2<JS_BITS_PER_WORD>::result;
*maskp = uintptr_t(1) << (offset & (JS_BITS_PER_WORD - 1));
}
};
} /* namespace js */
#endif