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Diffstat (limited to 'Build/source/libs/graphite2/graphite2-1.2.4/src/inc/bits.h')
-rw-r--r-- | Build/source/libs/graphite2/graphite2-1.2.4/src/inc/bits.h | 90 |
1 files changed, 90 insertions, 0 deletions
diff --git a/Build/source/libs/graphite2/graphite2-1.2.4/src/inc/bits.h b/Build/source/libs/graphite2/graphite2-1.2.4/src/inc/bits.h new file mode 100644 index 00000000000..908049f7285 --- /dev/null +++ b/Build/source/libs/graphite2/graphite2-1.2.4/src/inc/bits.h @@ -0,0 +1,90 @@ +/* GRAPHITE2 LICENSING + + Copyright 2012, SIL International + All rights reserved. + + This library is free software; you can redistribute it and/or modify + it under the terms of the GNU Lesser General Public License as published + by the Free Software Foundation; either version 2.1 of License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should also have received a copy of the GNU Lesser General Public + License along with this library in the file named "LICENSE". + If not, write to the Free Software Foundation, 51 Franklin Street, + Suite 500, Boston, MA 02110-1335, USA or visit their web page on the + internet at http://www.fsf.org/licenses/lgpl.html. + +Alternatively, the contents of this file may be used under the terms of the +Mozilla Public License (http://mozilla.org/MPL) or the GNU General Public +License, as published by the Free Software Foundation, either version 2 +of the License or (at your option) any later version. +*/ +#pragma once + +namespace graphite2 +{ + +template<typename T> +inline unsigned int bit_set_count(T v) +{ + v = v - ((v >> 1) & T(~T(0)/3)); // temp + v = (v & T(~T(0)/15*3)) + ((v >> 2) & T(~T(0)/15*3)); // temp + v = (v + (v >> 4)) & T(~T(0)/255*15); // temp + return (T)(v * T(~T(0)/255)) >> (sizeof(T)-1)*8; // count +} + + +template<int S> +inline unsigned long _mask_over_val(unsigned long v) +{ + v = _mask_over_val<S/2>(v); + v |= v >> S*4; + return v; +} + +template<> +inline unsigned long _mask_over_val<1>(unsigned long v) +{ + v |= v >> 1; + v |= v >> 2; + v |= v >> 4; + return v; +} + +template<typename T> +inline T mask_over_val(T v) +{ + return _mask_over_val<sizeof(T)>(v); +} + +template<typename T> +inline unsigned long next_highest_power2(T v) +{ + return _mask_over_val<sizeof(T)>(v-1)+1; +} + +template<typename T> +inline unsigned int log_binary(T v) +{ + return bit_set_count(mask_over_val(v))-1; +} + +template<typename T> +inline T has_zero(const T x) +{ + return (x - T(~T(0)/255)) & ~x & T(~T(0)/255*128); +} + +template<typename T> +inline T zero_bytes(const T x, unsigned char n) +{ + const T t = T(~T(0)/255*n); + return T((has_zero(x^t) >> 7)*n); +} + +} |