gfx/harfbuzz/src/hb-cache-private.hh@6474c204b198 (annotated)
gfx/harfbuzz/src/hb-cache-private.hh
Wed, 31 Dec 2014 06:09:35 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Wed, 31 Dec 2014 06:09:35 +0100
- changeset 0
- 6474c204b198
- permissions
- -rw-r--r--
Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.
| michael@0 | 1 | /* |
| michael@0 | 2 | * Copyright © 2012 Google, Inc. |
| michael@0 | 3 | * |
| michael@0 | 4 | * This is part of HarfBuzz, a text shaping library. |
| michael@0 | 5 | * |
| michael@0 | 6 | * Permission is hereby granted, without written agreement and without |
| michael@0 | 7 | * license or royalty fees, to use, copy, modify, and distribute this |
| michael@0 | 8 | * software and its documentation for any purpose, provided that the |
| michael@0 | 9 | * above copyright notice and the following two paragraphs appear in |
| michael@0 | 10 | * all copies of this software. |
| michael@0 | 11 | * |
| michael@0 | 12 | * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR |
| michael@0 | 13 | * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES |
| michael@0 | 14 | * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN |
| michael@0 | 15 | * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH |
| michael@0 | 16 | * DAMAGE. |
| michael@0 | 17 | * |
| michael@0 | 18 | * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, |
| michael@0 | 19 | * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND |
| michael@0 | 20 | * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS |
| michael@0 | 21 | * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO |
| michael@0 | 22 | * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. |
| michael@0 | 23 | * |
| michael@0 | 24 | * Google Author(s): Behdad Esfahbod |
| michael@0 | 25 | */ |
| michael@0 | 26 | |
| michael@0 | 27 | #ifndef HB_CACHE_PRIVATE_HH |
| michael@0 | 28 | #define HB_CACHE_PRIVATE_HH |
| michael@0 | 29 | |
| michael@0 | 30 | #include "hb-private.hh" |
| michael@0 | 31 | |
| michael@0 | 32 | |
| michael@0 | 33 | /* Implements a lock-free cache for int->int functions. */ |
| michael@0 | 34 | |
| michael@0 | 35 | template <unsigned int key_bits, unsigned int value_bits, unsigned int cache_bits> |
| michael@0 | 36 | struct hb_cache_t |
| michael@0 | 37 | { |
| michael@0 | 38 | ASSERT_STATIC (key_bits >= cache_bits); |
| michael@0 | 39 | ASSERT_STATIC (key_bits + value_bits - cache_bits < 8 * sizeof (unsigned int)); |
| michael@0 | 40 | |
| michael@0 | 41 | inline void clear (void) |
| michael@0 | 42 | { |
| michael@0 | 43 | memset (values, 255, sizeof (values)); |
| michael@0 | 44 | } |
| michael@0 | 45 | |
| michael@0 | 46 | inline bool get (unsigned int key, unsigned int *value) |
| michael@0 | 47 | { |
| michael@0 | 48 | unsigned int k = key & ((1<<cache_bits)-1); |
| michael@0 | 49 | unsigned int v = values[k]; |
| michael@0 | 50 | if ((v >> value_bits) != (key >> cache_bits)) |
| michael@0 | 51 | return false; |
| michael@0 | 52 | *value = v & ((1<<value_bits)-1); |
| michael@0 | 53 | return true; |
| michael@0 | 54 | } |
| michael@0 | 55 | |
| michael@0 | 56 | inline bool set (unsigned int key, unsigned int value) |
| michael@0 | 57 | { |
| michael@0 | 58 | if (unlikely ((key >> key_bits) || (value >> value_bits))) |
| michael@0 | 59 | return false; /* Overflows */ |
| michael@0 | 60 | unsigned int k = key & ((1<<cache_bits)-1); |
| michael@0 | 61 | unsigned int v = ((key>>cache_bits)<<value_bits) | value; |
| michael@0 | 62 | values[k] = v; |
| michael@0 | 63 | return true; |
| michael@0 | 64 | } |
| michael@0 | 65 | |
| michael@0 | 66 | private: |
| michael@0 | 67 | unsigned int values[1<<cache_bits]; |
| michael@0 | 68 | }; |
| michael@0 | 69 | |
| michael@0 | 70 | typedef hb_cache_t<21, 16, 8> hb_cmap_cache_t; |
| michael@0 | 71 | typedef hb_cache_t<16, 24, 8> hb_advance_cache_t; |
| michael@0 | 72 | |
| michael@0 | 73 | |
| michael@0 | 74 | #endif /* HB_CACHE_PRIVATE_HH */ |
