1 files changed, 146 insertions, 0 deletions
diff --git a/gfx/graphite2/src/inc/bits.h b/gfx/graphite2/src/inc/bits.h
new file mode 100644
index 000000000..615c6cba6
--- /dev/null
+++ b/gfx/graphite2/src/inc/bits.h
@@ -0,0 +1,146 @@
+/*  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
+{
+
+
+#if defined GRAPHITE2_BUILTINS && (defined __GNUC__ || defined __clang__)
+
+template<typename T>
+inline unsigned int bit_set_count(T v)
+{
+    return __builtin_popcount(v);
+}
+
+template<>
+inline unsigned int bit_set_count(int16 v)
+{
+    return __builtin_popcount(static_cast<uint16>(v));
+}
+
+template<>
+inline unsigned int bit_set_count(int8 v)
+{
+    return __builtin_popcount(static_cast<uint8>(v));
+}
+
+template<>
+inline unsigned int bit_set_count(unsigned long v)
+{
+    return __builtin_popcountl(v);
+}
+
+template<>
+inline unsigned int bit_set_count(signed long v)
+{
+    return __builtin_popcountl(v);
+}
+
+template<>
+inline unsigned int bit_set_count(unsigned long long v)
+{
+    return __builtin_popcountll(v);
+}
+
+template<>
+inline unsigned int bit_set_count(signed long long v)
+{
+    return __builtin_popcountll(v);
+}
+#else
+
+template<typename T>
+inline unsigned int bit_set_count(T v)
+{
+    v = v - ((v >> 1) & T(~(0UL)/3));                           // temp
+    v = (v & T(~(0UL)/15*3)) + ((v >> 2) & T(~(0UL)/15*3));     // temp
+    v = (v + (v >> 4)) & T(~(0UL)/255*15);                      // temp
+    return (T)(v * T(~(0UL)/255)) >> (sizeof(T)-1)*8;           // count
+}
+
+#endif
+
+
+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);
+}
+
+#if 0
+inline float float_round(float x, uint32 m)
+{
+    *reinterpret_cast<unsigned int *>(&x) &= m;
+    return *reinterpret_cast<float *>(&x);
+}
+#endif
+
+}