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Re: FWD: FLOATING-POINT CONSISTENCY, -FFLOAT-STORE, AND X86
Harvey J. Stein wrote:
> > For a thoroughly 32-bit application like mine, 16-byte spills are four
> > times as large as necessary - and yes, having all this data move in and
> > out of registers does have a cost (think cache footprint).
>
> That's true, but, like I said, it's 10 byte, not 16 byte, and it's vs
> the current 8 byte. There's currently no option of doing 4 byte
> spills.
Ah, that could be; I am not really up to snuff on the stuff reload can
and cannot do (would be a nice optimisation, though).
On the 10 vs. 16 byte issue: This probably depends on the type of your
Intel processor (see for instance
http://www.geocities.com/SiliconValley/9498/pentopt.html) - the value
that's important is the number of bytes in a cache line, because that's
the number reserved / transferrd.
Cheers,
--
Toon Moene (toon@moene.indiv.nluug.nl)
Saturnushof 14, 3738 XG Maartensdijk, The Netherlands
Phone: +31 346 214290; Fax: +31 346 214286
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