diff options
Diffstat (limited to 'src/extensions/ngram/nthbit.cc')
| -rw-r--r-- | src/extensions/ngram/nthbit.cc | 107 |
1 files changed, 107 insertions, 0 deletions
diff --git a/src/extensions/ngram/nthbit.cc b/src/extensions/ngram/nthbit.cc new file mode 100644 index 0000000..7b006e7 --- /dev/null +++ b/src/extensions/ngram/nthbit.cc @@ -0,0 +1,107 @@ + +// Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. +// +// Copyright 2005-2010 Google, Inc. +// Author: sorenj@google.com (Jeffrey Sorensen + +#include <fst/extensions/ngram/nthbit.h> + +// +// This table is generate using: +// +// unsigned int nth_bit_scan(uint64 v, unsigned int r) { +// int i=0; +// for (; i<64; i++) { +// if ((r -= v & 1) == 0) return i; +// v >>= 1; +// } +// return i; +// } +// +// for (size_t i = 0; i < 256; ++i) { +// uint32 offsets = 0; +// for (size_t b = 1; b <= 8; ++b) { +// uint32 offset = min<uint32>(nth_bit_scan(i, b), 8); +// offsets |= (offset << ((b - 1) << 2)); +// } +// bit_offset = offsets; +// printf("0x%x, ", bit_offset); +// if (i % 4 == 3) printf("\n"); +// } +// +uint32 nth_bit_bit_offset[] = { +0x88888888, 0x88888880, 0x88888881, 0x88888810, +0x88888882, 0x88888820, 0x88888821, 0x88888210, +0x88888883, 0x88888830, 0x88888831, 0x88888310, +0x88888832, 0x88888320, 0x88888321, 0x88883210, +0x88888884, 0x88888840, 0x88888841, 0x88888410, +0x88888842, 0x88888420, 0x88888421, 0x88884210, +0x88888843, 0x88888430, 0x88888431, 0x88884310, +0x88888432, 0x88884320, 0x88884321, 0x88843210, +0x88888885, 0x88888850, 0x88888851, 0x88888510, +0x88888852, 0x88888520, 0x88888521, 0x88885210, +0x88888853, 0x88888530, 0x88888531, 0x88885310, +0x88888532, 0x88885320, 0x88885321, 0x88853210, +0x88888854, 0x88888540, 0x88888541, 0x88885410, +0x88888542, 0x88885420, 0x88885421, 0x88854210, +0x88888543, 0x88885430, 0x88885431, 0x88854310, +0x88885432, 0x88854320, 0x88854321, 0x88543210, +0x88888886, 0x88888860, 0x88888861, 0x88888610, +0x88888862, 0x88888620, 0x88888621, 0x88886210, +0x88888863, 0x88888630, 0x88888631, 0x88886310, +0x88888632, 0x88886320, 0x88886321, 0x88863210, +0x88888864, 0x88888640, 0x88888641, 0x88886410, +0x88888642, 0x88886420, 0x88886421, 0x88864210, +0x88888643, 0x88886430, 0x88886431, 0x88864310, +0x88886432, 0x88864320, 0x88864321, 0x88643210, +0x88888865, 0x88888650, 0x88888651, 0x88886510, +0x88888652, 0x88886520, 0x88886521, 0x88865210, +0x88888653, 0x88886530, 0x88886531, 0x88865310, +0x88886532, 0x88865320, 0x88865321, 0x88653210, +0x88888654, 0x88886540, 0x88886541, 0x88865410, +0x88886542, 0x88865420, 0x88865421, 0x88654210, +0x88886543, 0x88865430, 0x88865431, 0x88654310, +0x88865432, 0x88654320, 0x88654321, 0x86543210, +0x88888887, 0x88888870, 0x88888871, 0x88888710, +0x88888872, 0x88888720, 0x88888721, 0x88887210, +0x88888873, 0x88888730, 0x88888731, 0x88887310, +0x88888732, 0x88887320, 0x88887321, 0x88873210, +0x88888874, 0x88888740, 0x88888741, 0x88887410, +0x88888742, 0x88887420, 0x88887421, 0x88874210, +0x88888743, 0x88887430, 0x88887431, 0x88874310, +0x88887432, 0x88874320, 0x88874321, 0x88743210, +0x88888875, 0x88888750, 0x88888751, 0x88887510, +0x88888752, 0x88887520, 0x88887521, 0x88875210, +0x88888753, 0x88887530, 0x88887531, 0x88875310, +0x88887532, 0x88875320, 0x88875321, 0x88753210, +0x88888754, 0x88887540, 0x88887541, 0x88875410, +0x88887542, 0x88875420, 0x88875421, 0x88754210, +0x88887543, 0x88875430, 0x88875431, 0x88754310, +0x88875432, 0x88754320, 0x88754321, 0x87543210, +0x88888876, 0x88888760, 0x88888761, 0x88887610, +0x88888762, 0x88887620, 0x88887621, 0x88876210, +0x88888763, 0x88887630, 0x88887631, 0x88876310, +0x88887632, 0x88876320, 0x88876321, 0x88763210, +0x88888764, 0x88887640, 0x88887641, 0x88876410, +0x88887642, 0x88876420, 0x88876421, 0x88764210, +0x88887643, 0x88876430, 0x88876431, 0x88764310, +0x88876432, 0x88764320, 0x88764321, 0x87643210, +0x88888765, 0x88887650, 0x88887651, 0x88876510, +0x88887652, 0x88876520, 0x88876521, 0x88765210, +0x88887653, 0x88876530, 0x88876531, 0x88765310, +0x88876532, 0x88765320, 0x88765321, 0x87653210, +0x88887654, 0x88876540, 0x88876541, 0x88765410, +0x88876542, 0x88765420, 0x88765421, 0x87654210, +0x88876543, 0x88765430, 0x88765431, 0x87654310, +0x88765432, 0x87654320, 0x87654321, 0x76543210, +}; |