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Diffstat (limited to 'lib/u64.h')
| -rw-r--r-- | lib/u64.h | 181 |
1 files changed, 181 insertions, 0 deletions
diff --git a/lib/u64.h b/lib/u64.h new file mode 100644 index 0000000..8a99335 --- /dev/null +++ b/lib/u64.h @@ -0,0 +1,181 @@ +/* uint64_t-like operations that work even on hosts lacking uint64_t + + Copyright (C) 2006, 2009-2023 Free Software Foundation, Inc. + + 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 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 Lesser General Public License for more details. + + 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 Paul Eggert. */ + +/* This file uses _GL_INLINE_HEADER_BEGIN, _GL_INLINE. */ +#if !_GL_CONFIG_H_INCLUDED + #error "Please include config.h first." +#endif + +#include <stdint.h> + +_GL_INLINE_HEADER_BEGIN +#ifndef _GL_U64_INLINE +# define _GL_U64_INLINE _GL_INLINE +#endif + +/* Return X rotated left by N bits, where 0 < N < 64. */ +#define u64rol(x, n) u64or (u64shl (x, n), u64shr (x, 64 - n)) + +#ifdef UINT64_MAX + +/* Native implementations are trivial. See below for comments on what + these operations do. */ +typedef uint64_t u64; +# define u64hilo(hi, lo) ((u64) (((u64) (hi) << 32) + (lo))) +# define u64init(hi, lo) u64hilo (hi, lo) +# define u64lo(x) ((u64) (x)) +# define u64size(x) u64lo (x) +# define u64lt(x, y) ((x) < (y)) +# define u64and(x, y) ((x) & (y)) +# define u64or(x, y) ((x) | (y)) +# define u64xor(x, y) ((x) ^ (y)) +# define u64plus(x, y) ((x) + (y)) +# define u64shl(x, n) ((x) << (n)) +# define u64shr(x, n) ((x) >> (n)) + +#else + +/* u64 is a 64-bit unsigned integer value. + u64init (HI, LO), is like u64hilo (HI, LO), but for use in + initializer contexts. */ +# ifdef WORDS_BIGENDIAN +typedef struct { uint32_t hi, lo; } u64; +# define u64init(hi, lo) { hi, lo } +# else +typedef struct { uint32_t lo, hi; } u64; +# define u64init(hi, lo) { lo, hi } +# endif + +/* Given the high and low-order 32-bit quantities HI and LO, return a u64 + value representing (HI << 32) + LO. */ +_GL_U64_INLINE u64 +u64hilo (uint32_t hi, uint32_t lo) +{ + u64 r; + r.hi = hi; + r.lo = lo; + return r; +} + +/* Return a u64 value representing LO. */ +_GL_U64_INLINE u64 +u64lo (uint32_t lo) +{ + u64 r; + r.hi = 0; + r.lo = lo; + return r; +} + +/* Return a u64 value representing SIZE. */ +_GL_U64_INLINE u64 +u64size (size_t size) +{ + u64 r; + r.hi = size >> 31 >> 1; + r.lo = size; + return r; +} + +/* Return X < Y. */ +_GL_U64_INLINE int +u64lt (u64 x, u64 y) +{ + return x.hi < y.hi || (x.hi == y.hi && x.lo < y.lo); +} + +/* Return X & Y. */ +_GL_U64_INLINE u64 +u64and (u64 x, u64 y) +{ + u64 r; + r.hi = x.hi & y.hi; + r.lo = x.lo & y.lo; + return r; +} + +/* Return X | Y. */ +_GL_U64_INLINE u64 +u64or (u64 x, u64 y) +{ + u64 r; + r.hi = x.hi | y.hi; + r.lo = x.lo | y.lo; + return r; +} + +/* Return X ^ Y. */ +_GL_U64_INLINE u64 +u64xor (u64 x, u64 y) +{ + u64 r; + r.hi = x.hi ^ y.hi; + r.lo = x.lo ^ y.lo; + return r; +} + +/* Return X + Y. */ +_GL_U64_INLINE u64 +u64plus (u64 x, u64 y) +{ + u64 r; + r.lo = x.lo + y.lo; + r.hi = x.hi + y.hi + (r.lo < x.lo); + return r; +} + +/* Return X << N. */ +_GL_U64_INLINE u64 +u64shl (u64 x, int n) +{ + u64 r; + if (n < 32) + { + r.hi = (x.hi << n) | (x.lo >> (32 - n)); + r.lo = x.lo << n; + } + else + { + r.hi = x.lo << (n - 32); + r.lo = 0; + } + return r; +} + +/* Return X >> N. */ +_GL_U64_INLINE u64 +u64shr (u64 x, int n) +{ + u64 r; + if (n < 32) + { + r.hi = x.hi >> n; + r.lo = (x.hi << (32 - n)) | (x.lo >> n); + } + else + { + r.hi = 0; + r.lo = x.hi >> (n - 32); + } + return r; +} + +#endif + +_GL_INLINE_HEADER_END |