Re: FWD: FLOATING-POINT CONSISTENCY, -FFLOAT-STORE, AND X86

[Toon Moene <toon@moene.indiv.nluug.nl>]

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
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