| /* Copyright (C) 2011-2014 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| Contributed by Chris Metcalf <cmetcalf@tilera.com>, 2011. |
| |
| The GNU C 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 the License, or (at your option) any later version. |
| |
| The GNU C Library 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 have received a copy of the GNU Lesser General Public |
| License along with the GNU C Library. If not, see |
| <http://www.gnu.org/licenses/>. */ |
| |
| /* Provide a mask based on the pointer alignment that |
| sets up non-zero bytes before the beginning of the string. |
| The MASK expression works because shift counts are taken mod 64. |
| Also, specify how to count "first" and "last" bits |
| when the bits have been read as a word. */ |
| |
| #include <stdint.h> |
| |
| #ifndef __BIG_ENDIAN__ |
| #define MASK(x) (__insn_shl(1ULL, (x << 3)) - 1) |
| #define NULMASK(x) ((2ULL << x) - 1) |
| #define CFZ(x) __insn_ctz(x) |
| #define REVCZ(x) __insn_clz(x) |
| #else |
| #define MASK(x) (__insn_shl(-2LL, ((-x << 3) - 1))) |
| #define NULMASK(x) (-2LL << (63 - x)) |
| #define CFZ(x) __insn_clz(x) |
| #define REVCZ(x) __insn_ctz(x) |
| #endif |
| |
| /* Create eight copies of the byte in a uint64_t. */ |
| static inline uint64_t copy_byte(uint8_t byte) |
| { |
| uint64_t word = byte; |
| word = __insn_bfins(word, word, 8, 15); |
| word = __insn_bfins(word, word, 16, 31); |
| word = __insn_bfins(word, word, 32, 63); |
| return word; |
| } |