/* * Copyright © 2012 Google, Inc. * * This is part of HarfBuzz, a text shaping library. * * Permission is hereby granted, without written agreement and without * license or royalty fees, to use, copy, modify, and distribute this * software and its documentation for any purpose, provided that the * above copyright notice and the following two paragraphs appear in * all copies of this software. * * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH * DAMAGE. * * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. * * Google Author(s): Behdad Esfahbod */ #ifndef HB_CACHE_HH #define HB_CACHE_HH #include "hb.hh" /* Implements a lockfree cache for int->int functions. * * The cache is a fixed-size array of 16-bit or 32-bit integers. * The key is split into two parts: the cache index and the rest. * * The cache index is used to index into the array. The rest is used * to store the key and the value. * * The value is stored in the least significant bits of the integer. * The key is stored in the most significant bits of the integer. * The key is shifted by cache_bits to the left to make room for the * value. */ template <unsigned int key_bits=16, unsigned int value_bits=8 + 32 - key_bits, unsigned int cache_bits=8, bool thread_safe=true> struct hb_cache_t { … }; #endif /* HB_CACHE_HH */