From: daniel_james_at_[hidden]
Date: 2008-05-11 09:09:06
Author: danieljames
Date: 2008-05-11 09:09:05 EDT (Sun, 11 May 2008)
New Revision: 45277
URL: http://svn.boost.org/trac/boost/changeset/45277
Log:
Put the prime number list into a template so that they (hopefully) only get included once.
Text files modified:
branches/unordered/trunk/boost/unordered/detail/hash_table.hpp | 26 ++++++++++++++++++--------
1 files changed, 18 insertions(+), 8 deletions(-)
Modified: branches/unordered/trunk/boost/unordered/detail/hash_table.hpp
==============================================================================
--- branches/unordered/trunk/boost/unordered/detail/hash_table.hpp (original)
+++ branches/unordered/trunk/boost/unordered/detail/hash_table.hpp 2008-05-11 09:09:05 EDT (Sun, 11 May 2008)
@@ -78,7 +78,13 @@
// prime number list, accessor
- static const std::size_t prime_list[] = {
+ template<typename T> struct prime_list_template
+ {
+ static std::size_t const value[];
+ };
+
+ template<typename T>
+ std::size_t const prime_list_template<T>::value[] = {
53ul, 97ul, 193ul, 389ul, 769ul,
1543ul, 3079ul, 6151ul, 12289ul, 24593ul,
49157ul, 98317ul, 196613ul, 393241ul, 786433ul,
@@ -86,12 +92,15 @@
50331653ul, 100663319ul, 201326611ul, 402653189ul, 805306457ul,
1610612741ul, 3221225473ul, 4294967291ul };
+ typedef prime_list_template<std::size_t> prime_list;
+
// no throw
inline std::size_t next_prime(std::size_t n) {
- std::size_t const* const prime_list_end = prime_list +
- sizeof(prime_list) / sizeof(*prime_list);
+ std::size_t const* const prime_list_begin = prime_list::value;
+ std::size_t const* const prime_list_end = prime_list_begin +
+ sizeof(prime_list::value) / sizeof(*prime_list::value);
std::size_t const* bound =
- std::lower_bound(prime_list,prime_list_end, n);
+ std::lower_bound(prime_list_begin, prime_list_end, n);
if(bound == prime_list_end)
bound--;
return *bound;
@@ -99,11 +108,12 @@
// no throw
inline std::size_t prev_prime(std::size_t n) {
- std::size_t const* const prime_list_end = prime_list +
- sizeof(prime_list) / sizeof(*prime_list);
+ std::size_t const* const prime_list_begin = prime_list::value;
+ std::size_t const* const prime_list_end = prime_list_begin +
+ sizeof(prime_list::value) / sizeof(*prime_list::value);
std::size_t const* bound =
- std::upper_bound(prime_list,prime_list_end, n);
- if(bound != prime_list)
+ std::upper_bound(prime_list_begin,prime_list_end, n);
+ if(bound != prime_list_begin)
bound--;
return *bound;
}