root/lib/u64.h

INCLUDED FROM

DEFINITIONS

1. u64hilo
2. u64lo
3. u64size
4. u64lt
5. u64and
6. u64or
7. u64xor
8. u64plus
9. u64shl
10. u64shr

     1 /* uint64_t-like operations that work even on hosts lacking uint64_t
     2 
     3    Copyright (C) 2006, 2009-2023 Free Software Foundation, Inc.
     4 
     5    This file is free software: you can redistribute it and/or modify
     6    it under the terms of the GNU Lesser General Public License as
     7    published by the Free Software Foundation; either version 2.1 of the
     8    License, or (at your option) any later version.
     9 
    10    This file is distributed in the hope that it will be useful,
    11    but WITHOUT ANY WARRANTY; without even the implied warranty of
    12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    13    GNU Lesser General Public License for more details.
    14 
    15    You should have received a copy of the GNU Lesser General Public License
    16    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
    17 
    18 /* Written by Paul Eggert.  */
    19 
    20 #include <stdint.h>
    21 
    22 #ifndef _GL_INLINE_HEADER_BEGIN
    23  #error "Please include config.h first."
    24 #endif
    25 _GL_INLINE_HEADER_BEGIN
    26 #ifndef _GL_U64_INLINE
    27 # define _GL_U64_INLINE _GL_INLINE
    28 #endif
    29 
    30 /* Return X rotated left by N bits, where 0 < N < 64.  */
    31 #define u64rol(x, n) u64or (u64shl (x, n), u64shr (x, 64 - n))
    32 
    33 #ifdef UINT64_MAX
    34 
    35 /* Native implementations are trivial.  See below for comments on what
    36    these operations do.  */
    37 typedef uint64_t u64;
    38 # define u64hilo(hi, lo) ((u64) (((u64) (hi) << 32) + (lo)))
    39 # define u64init(hi, lo) u64hilo (hi, lo)
    40 # define u64lo(x) ((u64) (x))
    41 # define u64size(x) u64lo (x)
    42 # define u64lt(x, y) ((x) < (y))
    43 # define u64and(x, y) ((x) & (y))
    44 # define u64or(x, y) ((x) | (y))
    45 # define u64xor(x, y) ((x) ^ (y))
    46 # define u64plus(x, y) ((x) + (y))
    47 # define u64shl(x, n) ((x) << (n))
    48 # define u64shr(x, n) ((x) >> (n))
    49 
    50 #else
    51 
    52 /* u64 is a 64-bit unsigned integer value.
    53    u64init (HI, LO), is like u64hilo (HI, LO), but for use in
    54    initializer contexts.  */
    55 # ifdef WORDS_BIGENDIAN
    56 typedef struct { uint32_t hi, lo; } u64;
    57 #  define u64init(hi, lo) { hi, lo }
    58 # else
    59 typedef struct { uint32_t lo, hi; } u64;
    60 #  define u64init(hi, lo) { lo, hi }
    61 # endif
    62 
    63 /* Given the high and low-order 32-bit quantities HI and LO, return a u64
    64    value representing (HI << 32) + LO.  */
    65 _GL_U64_INLINE u64
    66 u64hilo (uint32_t hi, uint32_t lo)
    67 {
    68   u64 r;
    69   r.hi = hi;
    70   r.lo = lo;
    71   return r;
    72 }
    73 
    74 /* Return a u64 value representing LO.  */
    75 _GL_U64_INLINE u64
    76 u64lo (uint32_t lo)
    77 {
    78   u64 r;
    79   r.hi = 0;
    80   r.lo = lo;
    81   return r;
    82 }
    83 
    84 /* Return a u64 value representing SIZE.  */
    85 _GL_U64_INLINE u64
    86 u64size (size_t size)
    87 {
    88   u64 r;
    89   r.hi = size >> 31 >> 1;
    90   r.lo = size;
    91   return r;
    92 }
    93 
    94 /* Return X < Y.  */
    95 _GL_U64_INLINE int
    96 u64lt (u64 x, u64 y)
    97 {
    98   return x.hi < y.hi || (x.hi == y.hi && x.lo < y.lo);
    99 }
   100 
   101 /* Return X & Y.  */
   102 _GL_U64_INLINE u64
   103 u64and (u64 x, u64 y)
   104 {
   105   u64 r;
   106   r.hi = x.hi & y.hi;
   107   r.lo = x.lo & y.lo;
   108   return r;
   109 }
   110 
   111 /* Return X | Y.  */
   112 _GL_U64_INLINE u64
   113 u64or (u64 x, u64 y)
   114 {
   115   u64 r;
   116   r.hi = x.hi | y.hi;
   117   r.lo = x.lo | y.lo;
   118   return r;
   119 }
   120 
   121 /* Return X ^ Y.  */
   122 _GL_U64_INLINE u64
   123 u64xor (u64 x, u64 y)
   124 {
   125   u64 r;
   126   r.hi = x.hi ^ y.hi;
   127   r.lo = x.lo ^ y.lo;
   128   return r;
   129 }
   130 
   131 /* Return X + Y.  */
   132 _GL_U64_INLINE u64
   133 u64plus (u64 x, u64 y)
   134 {
   135   u64 r;
   136   r.lo = x.lo + y.lo;
   137   r.hi = x.hi + y.hi + (r.lo < x.lo);
   138   return r;
   139 }
   140 
   141 /* Return X << N.  */
   142 _GL_U64_INLINE u64
   143 u64shl (u64 x, int n)
   144 {
   145   u64 r;
   146   if (n < 32)
   147     {
   148       r.hi = (x.hi << n) | (x.lo >> (32 - n));
   149       r.lo = x.lo << n;
   150     }
   151   else
   152     {
   153       r.hi = x.lo << (n - 32);
   154       r.lo = 0;
   155     }
   156   return r;
   157 }
   158 
   159 /* Return X >> N.  */
   160 _GL_U64_INLINE u64
   161 u64shr (u64 x, int n)
   162 {
   163   u64 r;
   164   if (n < 32)
   165     {
   166       r.hi = x.hi >> n;
   167       r.lo = (x.hi << (32 - n)) | (x.lo >> n);
   168     }
   169   else
   170     {
   171       r.hi = 0;
   172       r.lo = x.hi >> (n - 32);
   173     }
   174   return r;
   175 }
   176 
   177 #endif
   178 
   179 _GL_INLINE_HEADER_END