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Fix corner case when calculating whether external indexes can be used when merging. "supports_aligned_trailing" should not take into account that the first range includes n_keys.

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Ion Gaztañaga 2018-06-27 16:55:14 +02:00
parent 97389fa595
commit ddeb234127
1 changed files with 29 additions and 6 deletions
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35
include/boost/move/algo/adaptive_merge.hpp
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@ -137,6 +137,30 @@ inline void adaptive_merge_final_merge( RandIt first
BOOST_MOVE_ADAPTIVE_SORT_PRINT_L1(" A fin mrg: ", len);
}
template<class SizeType>
inline static SizeType adaptive_merge_n_keys_without_external_keys(SizeType l_block, SizeType len1, SizeType len2, SizeType l_intbuf)
{
typedef SizeType size_type;
//This is the minimum number of keys to implement the ideal algorithm
size_type n_keys = len1/l_block+len2/l_block;
const size_type second_half_blocks = len2/l_block;
const size_type first_half_aux = len1-l_intbuf;
while(n_keys >= ((first_half_aux-n_keys)/l_block + second_half_blocks)){
--n_keys;
}
++n_keys;
return n_keys;
}
template<class SizeType>
inline static SizeType adaptive_merge_n_keys_with_external_keys(SizeType l_block, SizeType len1, SizeType len2, SizeType l_intbuf)
{
typedef SizeType size_type;
//This is the minimum number of keys to implement the ideal algorithm
size_type n_keys = (len1-l_intbuf)/l_block + len2/l_block;
return n_keys;
}
template<class SizeType, class Xbuf>
inline SizeType adaptive_merge_n_keys_intbuf(SizeType &rl_block, SizeType len1, SizeType len2, Xbuf & xbuf, SizeType &l_intbuf_inout)
{
@ -149,14 +173,13 @@ inline SizeType adaptive_merge_n_keys_intbuf(SizeType &rl_block, SizeType len1,
}
//This is the minimum number of keys to implement the ideal algorithm
size_type n_keys = len1/l_block+len2/l_block;
while(n_keys >= ((len1-l_intbuf-n_keys)/l_block + len2/l_block)){
--n_keys;
}
++n_keys;
size_type n_keys = adaptive_merge_n_keys_without_external_keys(l_block, len1, len2, l_intbuf);
BOOST_ASSERT(n_keys >= ((len1-l_intbuf-n_keys)/l_block + len2/l_block));
if(xbuf.template supports_aligned_trailing<size_type>(l_block, n_keys)){
if(xbuf.template supports_aligned_trailing<size_type>
( l_block
, adaptive_merge_n_keys_with_external_keys(l_block, len1, len2, l_intbuf)))
{
n_keys = 0u;
}
l_intbuf_inout = l_intbuf;