X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Fbitrotate.h;h=d4911d0b2d83c2c0b6ee1c914673d04474a27598;hb=38db1b35bf51a7a738f27d2660a9fdd3b46447be;hp=f3b6a66477fa81f2b19ac3bb39fcda5215301f1c;hpb=ca19d955ebaa690b5580bb8c18ca20ab5daf8fff;p=gnulib.git

diff --git a/lib/bitrotate.h b/lib/bitrotate.h
index f3b6a6647..d4911d0b2 100644
--- a/lib/bitrotate.h
+++ b/lib/bitrotate.h
@@ -21,13 +21,33 @@
 
 #include <stdint.h>
 
+#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. */
+static 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.*/
+static 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. */
 static inline uint32_t
 rotl32 (uint32_t x, int n)
 {
-  return ((x << n) | (x >> (32 - n))) & 0xFFFFFFFF;
+  return ((x << n) | (x >> (32 - n))) & UINT32_MAX;
 }
 
 /* Given an unsigned 32-bit argument X, return the value corresponding
@@ -36,25 +56,51 @@ rotl32 (uint32_t x, int n)
 static inline uint32_t
 rotr32 (uint32_t x, int n)
 {
-  return ((x >> n) | (x << (32 - n))) & 0xFFFFFFFF;
+  return ((x >> n) | (x << (32 - n))) & UINT32_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. */
+   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. */
 static inline uint16_t
 rotl16 (uint16_t x, int n)
 {
-  return ((x << n) | (x >> (16 - n))) & 0xFFFFFFFF;
+  return ((x << n) | (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. */
+   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. */
 static inline uint16_t
 rotr16 (uint16_t x, int n)
 {
-  return ((x >> n) | (x << (16 - n))) & 0xFFFFFFFF;
+  return ((x >> n) | (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. */
+static inline uint8_t
+rotl8 (uint8_t x, int n)
+{
+  return ((x << n) | (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. */
+static inline uint8_t
+rotr8 (uint8_t x, int n)
+{
+  return ((x >> n) | (x << (8 - n))) & UINT8_MAX;
 }
 
 #endif /* _GL_BITROTATE_H */