From 96a32415ab43377cf1575bd3f4f2980f58028209 Mon Sep 17 00:00:00 2001 From: Determinant Date: Fri, 14 Aug 2015 11:51:42 +0800 Subject: add implementation for kaldi io (by ymz) --- .../openfst/include/fst/extensions/ngram/nthbit.h | 46 ++++++++++++++++++++++ 1 file changed, 46 insertions(+) create mode 100644 kaldi_io/src/tools/openfst/include/fst/extensions/ngram/nthbit.h (limited to 'kaldi_io/src/tools/openfst/include/fst/extensions/ngram/nthbit.h') diff --git a/kaldi_io/src/tools/openfst/include/fst/extensions/ngram/nthbit.h b/kaldi_io/src/tools/openfst/include/fst/extensions/ngram/nthbit.h new file mode 100644 index 0000000..d4a9a5a --- /dev/null +++ b/kaldi_io/src/tools/openfst/include/fst/extensions/ngram/nthbit.h @@ -0,0 +1,46 @@ + +// 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) +// dr@google.com (Doug Rohde) + +#ifndef FST_EXTENSIONS_NGRAM_NTHBIT_H_ +#define FST_EXTENSIONS_NGRAM_NTHBIT_H_ + +#include + +extern uint32 nth_bit_bit_offset[]; + +inline uint32 nth_bit(uint64 v, uint32 r) { + uint32 shift = 0; + uint32 c = __builtin_popcount(v & 0xffffffff); + uint32 mask = -(r > c); + r -= c & mask; + shift += (32 & mask); + + c = __builtin_popcount((v >> shift) & 0xffff); + mask = -(r > c); + r -= c & mask; + shift += (16 & mask); + + c = __builtin_popcount((v >> shift) & 0xff); + mask = -(r > c); + r -= c & mask; + shift += (8 & mask); + + return shift + ((nth_bit_bit_offset[(v >> shift) & 0xff] >> + ((r - 1) << 2)) & 0xf); +} + +#endif // FST_EXTENSIONS_NGRAM_NTHBIT_H_ -- cgit v1.2.3