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diff --git a/gl/lib/bitrotate.h b/gl/lib/bitrotate.h
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+/* bitrotate.h - Rotate bits in integers
+ Copyright (C) 2008-2022 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 Simon Josefsson <simon@josefsson.org>, 2008. */
+
+#ifndef _GL_BITROTATE_H
+#define _GL_BITROTATE_H
+
+#include <limits.h>
+#include <stdint.h>
+#include <sys/types.h>
+
+#ifndef _GL_INLINE_HEADER_BEGIN
+ #error "Please include config.h first."
+#endif
+_GL_INLINE_HEADER_BEGIN
+#ifndef BITROTATE_INLINE
+# define BITROTATE_INLINE _GL_INLINE
+#endif
+
+#ifdef UINT64_MAX
+/* Given an unsigned 64-bit argument X, return the value corresponding
+ to rotating the bits N steps to the left. N must be between 1 and
+ 63 inclusive. */
+BITROTATE_INLINE uint64_t
+rotl64 (uint64_t x, int n)
+{
+ return ((x << n) | (x >> (64 - n))) & UINT64_MAX;
+}
+
+/* Given an unsigned 64-bit argument X, return the value corresponding
+ to rotating the bits N steps to the right. N must be between 1 to
+ 63 inclusive.*/
+BITROTATE_INLINE uint64_t
+rotr64 (uint64_t x, int n)
+{
+ return ((x >> n) | (x << (64 - n))) & UINT64_MAX;
+}
+#endif
+
+/* Given an unsigned 32-bit argument X, return the value corresponding
+ to rotating the bits N steps to the left. N must be between 1 and
+ 31 inclusive. */
+BITROTATE_INLINE uint32_t
+rotl32 (uint32_t x, int n)
+{
+ return ((x << n) | (x >> (32 - n))) & UINT32_MAX;
+}
+
+/* Given an unsigned 32-bit argument X, return the value corresponding
+ to rotating the bits N steps to the right. N must be between 1 to
+ 31 inclusive.*/
+BITROTATE_INLINE uint32_t
+rotr32 (uint32_t x, int n)
+{
+ return ((x >> n) | (x << (32 - n))) & UINT32_MAX;
+}
+
+/* Given a size_t argument X, return the value corresponding
+ to rotating the bits N steps to the left. N must be between 1 and
+ (CHAR_BIT * sizeof (size_t) - 1) inclusive. */
+BITROTATE_INLINE size_t
+rotl_sz (size_t x, int n)
+{
+ return ((x << n) | (x >> ((CHAR_BIT * sizeof x) - n))) & SIZE_MAX;
+}
+
+/* Given a size_t argument X, return the value corresponding
+ to rotating the bits N steps to the right. N must be between 1 to
+ (CHAR_BIT * sizeof (size_t) - 1) inclusive. */
+BITROTATE_INLINE size_t
+rotr_sz (size_t x, int n)
+{
+ return ((x >> n) | (x << ((CHAR_BIT * sizeof x) - n))) & SIZE_MAX;
+}
+
+/* Given an unsigned 16-bit argument X, return the value corresponding
+ to rotating the bits N steps to the left. N must be between 1 to
+ 15 inclusive, but on most relevant targets N can also be 0 and 16
+ because 'int' is at least 32 bits and the arguments must widen
+ before shifting. */
+BITROTATE_INLINE uint16_t
+rotl16 (uint16_t x, int n)
+{
+ return (((unsigned int) x << n) | ((unsigned int) x >> (16 - n)))
+ & UINT16_MAX;
+}
+
+/* Given an unsigned 16-bit argument X, return the value corresponding
+ to rotating the bits N steps to the right. N must be in 1 to 15
+ inclusive, but on most relevant targets N can also be 0 and 16
+ because 'int' is at least 32 bits and the arguments must widen
+ before shifting. */
+BITROTATE_INLINE uint16_t
+rotr16 (uint16_t x, int n)
+{
+ return (((unsigned int) x >> n) | ((unsigned int) x << (16 - n)))
+ & UINT16_MAX;
+}
+
+/* Given an unsigned 8-bit argument X, return the value corresponding
+ to rotating the bits N steps to the left. N must be between 1 to 7
+ inclusive, but on most relevant targets N can also be 0 and 8
+ because 'int' is at least 32 bits and the arguments must widen
+ before shifting. */
+BITROTATE_INLINE uint8_t
+rotl8 (uint8_t x, int n)
+{
+ return (((unsigned int) x << n) | ((unsigned int) x >> (8 - n))) & UINT8_MAX;
+}
+
+/* Given an unsigned 8-bit argument X, return the value corresponding
+ to rotating the bits N steps to the right. N must be in 1 to 7
+ inclusive, but on most relevant targets N can also be 0 and 8
+ because 'int' is at least 32 bits and the arguments must widen
+ before shifting. */
+BITROTATE_INLINE uint8_t
+rotr8 (uint8_t x, int n)
+{
+ return (((unsigned int) x >> n) | ((unsigned int) x << (8 - n))) & UINT8_MAX;
+}
+
+_GL_INLINE_HEADER_END
+
+#endif /* _GL_BITROTATE_H */