[racket-dev] [plt] Push #28633: master branch updated

From: Matthew Flatt (mflatt at cs.utah.edu)
Date: Sun Apr 27 23:16:13 EDT 2014

At Sun, 27 Apr 2014 18:56:32 -0600, Neil Toronto wrote:
> Strange thing, though: while `inexact->exact` is now about 10x faster, 
> my TR implementation `flonum->rational` is now about 7x slower. I've 
> verified that `flonum->fields` accounts for about 85% of the running 
> time. I see that you've changed `integer-bytes->integer`, which 
> `flonum->fields` uses. Could it have been a pessimization on certain 
> platforms?

That's surprising. I don't expect the modified `integer-bytes->integer`
to be any slower.

Are you timing with the "flonum-to-racket.rkt" that you sent me? When I
run it on various machines (Mac 32-bit x86, Mac 64-bit x86, Mac 32-bit
PPC, Linux 64-bit x86, Windows 64-bit x86 VM), the time reported for
your code is not slower than before, and it's consistently within 50%
of the time reported for the new `inexact->exact`.

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