lkml.org 
[lkml]   [2000]   [Jan]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: Preventing gcc from aligning stack???
Date
From
Jamie Lokier <lkd@tantalophile.demon.co.uk> said:
> Stefan Monnier wrote:
> > >>>>> "H" == H Peter Anvin <hpa@transmeta.com> writes:
> > > ICK. I'd really like to see a version which spilled to extended
> > > precision.

> > Why should gcc spill a double (i.e. 64bit) as extended precision ?

> So that the behaviour of a program does not depend on whether a register
> is spilled. So that you get consistent results from the same code.

Floationg point code is by its very nature inexact. To force "exactness" on
it (at the cost of a very sizable performance loss) is not very
realistic. Anyway, it's in the end a flaw in the design of the ia32.

[...]

> Numerical codes, simple things like minimum finders and iterative
> solvers, depend on such behaviour.

How? An example, please.
--
Horst von Brand vonbrand@sleipnir.valparaiso.cl
Casilla 9G, Viña del Mar, Chile +56 32 672616

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 13:56    [from the cache]
©2003-2011 Jasper Spaans