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+/* uint64_t-like operations that work even on hosts lacking uint64_t
+
+ Copyright (C) 2006, 2009-2018 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 program 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.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <https://www.gnu.org/licenses/>. */
+
+/* Written by Paul Eggert. */
+
+#include <stdint.h>
+
+#ifndef _GL_INLINE_HEADER_BEGIN
+ #error "Please include config.h first."
+#endif
+_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