[Boost-bugs] [Boost C++ Libraries] #9232: Template bloat

Subject: [Boost-bugs] [Boost C++ Libraries] #9232: Template bloat
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2013-10-11 13:18:12

#9232: Template bloat
------------------------------+----------------------------
 Reporter:  psiha             |      Owner:  johnmaddock
     Type:  Bugs              |     Status:  new
Milestone:  To Be Determined  |  Component:  multiprecision
  Version:  Boost 1.54.0      |   Severity:  Optimization
 Keywords:                    |
------------------------------+----------------------------
 With integers of size N powm() will instantiate divide_unsigned_helper<>
 for N and N*2, since this is a very large function this leads to classical
 template bloat.
 Examining the codegen it appears that both instantiations are nearly
 identical save for immediate constants -> this would suggest that you
 could refactor divide_unsigned_helper<> (and probably the rest of the
 library) so that it separates functionality that actually depends on
 template parameters from template-parameter independent code into separate
 functions (in this case divide_unsigned_helper would probably call a
 helper function that takes the size of the number as a runtime parameter).

 ps. even when different function template instantiations result in
 identical code there are _still_ lousy compilers&linkers that will not
 merge them (Clang we are looking at you:
 http://llvm.org/bugs/show_bug.cgi?id=11633)...

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/9232>
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