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From: jrmarsha <jrmarsha@mtu.edu>
To: libc-help@sourceware.org
Subject: Considering merge optimizations from Timsort in __move_merge_adaptive, __move_merge_adaptive_backward
Date: Tue, 03 Jul 2018 04:16:00 -0000	[thread overview]
Message-ID: <3c1e0790-9e50-f27b-b78d-b9149517b3e6@mtu.edu> (raw)

Hello all,

I've been implementing a new version of Timsort in C++ using more 
standard facilities.  One thing I've come across which adds a divide 
between a larger codebase and faster code is the implementation of 
std::inplace_merge with sufficient memory.  This goes to the specific 
functions  __move_merge_adaptive, and __move_merge_adaptive_backward.  
In particular, there is an optimization where each insertion searches 
for the maximum number of elements it can move.  A brief in context 
explanation is here: 
https://en.wikipedia.org/wiki/Timsort#Individual_merges .  Would such a 
trick have a place in glibc or is the overhead likely too great in the 
general case?

             reply	other threads:[~2018-07-03  4:16 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-07-03  4:16 jrmarsha [this message]
2018-07-03 20:04 ` Carlos O'Donell
2018-07-03 20:10   ` jrmarsha
2018-07-03 23:30     ` Carlos O'Donell
2018-07-04 12:08       ` Adhemerval Zanella
2018-07-20  3:48       ` Joshua Marshall
2018-07-23 20:57         ` Carlos O'Donell

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