X-Git-Url: http://plrg.eecs.uci.edu/git/?p=libcds.git;a=blobdiff_plain;f=cds%2Falgo%2Fint_algo.h;h=cc6cfd26702430c3e76193fe13f349bc60c58201;hp=9fc772a2bc972d6ea4b084ecc977fcb7b333bbff;hb=2bb66f1d159d044d2c5dad0f0f968abcb6d53287;hpb=056d289619d45ccf1055c18d63cb3bad072a71a0

diff --git a/cds/algo/int_algo.h b/cds/algo/int_algo.h
index 9fc772a2..cc6cfd26 100644
--- a/cds/algo/int_algo.h
+++ b/cds/algo/int_algo.h
@@ -34,7 +34,7 @@
 #include <cds/algo/bitop.h>
 
 namespace cds { namespace beans {
-
+#if CDS_BUILD_BITS == 64
     /// Returns largest previous integer for <tt>log2( n )</tt>
     static inline size_t log2floor( size_t n )
     {
@@ -98,36 +98,68 @@ namespace cds { namespace beans {
         return is_power2(n) ? log2floor(n) : 0;
     }
 
-#if CDS_BUILD_BITS == 32
+#elif CDS_BUILD_BITS == 32
     //@cond
     // 64bit specializations
 
+/// Returns largest previous integer for <tt>log2( n )</tt>
     static inline uint64_t log2floor( uint64_t n )
     {
         return n ? cds::bitop::MSBnz( n ) : 0;
     }
 
+/// Returns smallest following integer for <tt>log2( n )</tt>
     static inline uint64_t log2ceil( uint64_t n )
     {
         uint64_t i = log2floor( n );
         return (uint64_t( 1 ) << i) < n ? i + 1 : i;
     }
 
+/// Returns largest previous power of 2 for \p n
+    /**
+        Examples:
+        \code
+        floor2(0) == 1   // !!!
+        floor2(1) == 1
+        floor2(2) == 2
+        floor2(3) == 2
+        floor2(4) == 4
+        floor2(15) == 8
+        floor2(16) == 16
+        floor2(17) == 16
+        \endcode
+    */
     static inline uint64_t floor2( uint64_t n )
     {
         return uint64_t( 1 ) << log2floor( n );
     }
 
+/// Returns smallest following power of 2 for \p n
+    /**
+        Examples:
+        \code
+        ceil2(0) == 1   // !!!
+        ceil2(1) == 1
+        ceil2(2) == 2
+        ceil2(3) == 4
+        ceil2(4) == 4
+        ceil2(15) == 16
+        ceil2(16) == 16
+        ceil2(17) == 32
+        \endcode
+    */
     static inline uint64_t ceil2( uint64_t n )
     {
         return uint64_t( 1 ) << log2ceil( n );
     }
 
+/// Checks if \p n is power of 2
     CDS_CONSTEXPR static inline bool is_power2( uint64_t n ) CDS_NOEXCEPT
     {
         return (n & (n - 1)) == 0 && n;
     }
 
+/// Returns binary logarithm of \p n if \p n is power of two, otherwise returns 0
     static inline uint64_t log2( uint64_t n )
     {
         return is_power2( n ) ? log2floor( n ) : 0;