diff options
Diffstat (limited to 'lib/count-leading-zeros.h')
| -rw-r--r-- | lib/count-leading-zeros.h | 29 |
1 files changed, 18 insertions, 11 deletions
diff --git a/lib/count-leading-zeros.h b/lib/count-leading-zeros.h index c8b3dc05110..354641af0a2 100644 --- a/lib/count-leading-zeros.h +++ b/lib/count-leading-zeros.h @@ -1,17 +1,17 @@ /* count-leading-zeros.h -- counts the number of leading 0 bits in a word. - Copyright (C) 2012-2017 Free Software Foundation, Inc. + Copyright (C) 2012-2022 Free Software Foundation, Inc. - This program is free software: you can redistribute it and/or modify - it under the terms of the GNU General Public License as published by - the Free Software Foundation; either version 3 of the License, or - (at your option) any later version. + This file 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. - This program is distributed in the hope that it will be useful, + This file 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 General Public License for more details. + GNU Lesser General Public License for more details. - You should have received a copy of the GNU General Public License + You should have received a copy of the GNU Lesser General Public License along with this program. If not, see <https://www.gnu.org/licenses/>. */ /* Written by Eric Blake. */ @@ -30,11 +30,16 @@ _GL_INLINE_HEADER_BEGIN # define COUNT_LEADING_ZEROS_INLINE _GL_INLINE #endif +#ifdef __cplusplus +extern "C" { +#endif + /* Assuming the GCC builtin is BUILTIN and the MSC builtin is MSC_BUILTIN, expand to code that computes the number of leading zeros of the local variable 'x' of type TYPE (an unsigned integer type) and return it from the current function. */ -#if __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 4) +#if __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 4) \ + || (__clang_major__ >= 4) # define COUNT_LEADING_ZEROS(BUILTIN, MSC_BUILTIN, TYPE) \ return x ? BUILTIN (x) : CHAR_BIT * sizeof x; #elif _MSC_VER @@ -71,7 +76,7 @@ COUNT_LEADING_ZEROS_INLINE int count_leading_zeros_32 (unsigned int x) { /* <https://github.com/gibsjose/BitHacks> - <http://www.fit.vutbr.cz/~ibarina/pub/bithacks.pdf> */ + <https://www.fit.vutbr.cz/~ibarina/pub/bithacks.pdf> */ static const char de_Bruijn_lookup[32] = { 31, 22, 30, 21, 18, 10, 29, 2, 20, 17, 15, 13, 9, 6, 28, 1, 23, 19, 11, 3, 16, 14, 7, 24, 12, 4, 8, 25, 5, 26, 27, 0 @@ -100,7 +105,6 @@ count_leading_zeros_l (unsigned long int x) COUNT_LEADING_ZEROS (__builtin_clzl, _BitScanReverse, unsigned long int); } -#if HAVE_UNSIGNED_LONG_LONG_INT /* Compute and return the number of leading zeros in X. */ COUNT_LEADING_ZEROS_INLINE int count_leading_zeros_ll (unsigned long long int x) @@ -108,6 +112,9 @@ count_leading_zeros_ll (unsigned long long int x) COUNT_LEADING_ZEROS (__builtin_clzll, _BitScanReverse64, unsigned long long int); } + +#ifdef __cplusplus +} #endif _GL_INLINE_HEADER_END |