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Re: Comments on the suggestion to use infinite precision math for wide int.
- From: Robert Dewar <dewar at adacore dot com>
- To: Lawrence Crowl <crowl at google dot com>
- Cc: Kenneth Zadeck <zadeck at naturalbridge dot com>, Florian Weimer <fweimer at redhat dot com>, Richard Biener <richard dot guenther at gmail dot com>, Mike Stump <mikestump at comcast dot net>, gcc-patches <gcc-patches at gcc dot gnu dot org>, rdsandiford at googlemail dot com, Ian Lance Taylor <iant at google dot com>
- Date: Mon, 08 Apr 2013 17:36:56 -0400
- Subject: Re: Comments on the suggestion to use infinite precision math for wide int.
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On 4/8/2013 5:12 PM, Lawrence Crowl wrote:
(BTW, you *really* don't need to quote entire messages, I find
it rather redundant for the entire thread to be in every message,
we all have thread following mail readers!)
Correct me if I'm wrong, but the Ada standard doesn't require any
particular maximum evaluation precision, but only that you get an
exception if the values exceed the chosen maximum.
Right, that's at run-time, at compile-time for static expressions,
infinite precision is required.
But at run-time, all three of the modes we provide are
standard conforming.
In essence, you have moved some of the optimization from the back
end to the front end. Correct?
Sorry, I don't quite understand that. If you are syaing that the
back end could handle this widening for intermediate values, sure
it could, this is the kind of thing that can be done at various
different places.