Preventing gcc from aligning stack???

[H. Peter Anvin]

Horst von Brand wrote:
> 
> "H. Peter Anvin" <hpa en transmeta.com> said:
> > Tuukka Toivonen wrote:
> > > On 25 Jan 2000, H. Peter Anvin wrote:
> > > > The native fp format on IA32 is "long double" -- 80 bits (10 bytes).
> 
> > > Yes, but this is not relevant here. The 10byte floating point is used in
> > > practice only internally to the FPU. Yes, you can read and store it but
> > > nobody does that, since it's so much slower than a normal float or double
> > > (on Pentium, atleast).
> 
> > You have to if you're going to spill a register.
> 
> gcc doesn't do that, it stores FP as doubles (8 bytes) always. This can
> give different results according to the way the computations are done
> (different roundings when storing different intermediates), so they provide
> the -ffloat-store option, which stores all intermediates to memory (rounds
> them to 8 bytes).
> 
> This is from egcs-1.1.2, but this hasn't changed in quite some time AFAIK.
> 

ICK.  I'd really like to see a version which spilled to extended
precision.

	-hpa

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