Re: [Boost-bugs] [Boost C++ Libraries] #12527: cpp_bin_float: Anal fixation. Part 3. Double rounding when result of convert_to<double>() is a subnormal

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #12527: cpp_bin_float: Anal fixation. Part 3. Double rounding when result of convert_to<double>() is a subnormal
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2016-11-17 11:31:22

#12527: cpp_bin_float: Anal fixation. Part 3. Double rounding when result of
convert_to<double>() is a subnormal
-------------------------------+----------------------------
  Reporter:  Michael Shatz     |      Owner:  johnmaddock
      Type:  Bugs              |     Status:  reopened
 Milestone:  To Be Determined  |  Component:  multiprecision
   Version:  Boost 1.62.0      |   Severity:  Problem
Resolution:                    |   Keywords:
-------------------------------+----------------------------

Comment (by Michael Shatz):

 Thank you

 Unfortunately, tonight I have more important things to do. Like watching
 Carlsen vs Karjakin ;-)

 Most likely, I wouldn't test it until Saturday night.

 Sorry

 P.S.

 Variant in comment 15 is non-trivially faster than comment 14. Especially
 for cpp_bin_float_100.

 But yes, even without measurement I can believe that using low-level
 cpp_bin_float primitives can be faster than using relatively high-level
 eval_convert_to(uint64_t*, cpp_bin_float*).

 On the other hand, if the difference (aginst variant in comment 15) is as
 significant as you suggest, it means that  eval_convert_to(uint64_t*,
 cpp_bin_float*) is undertuned.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/12527#comment:19>
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