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DateMon, 17 Jul 2006 16:50:02 +0100
FromPaulo Marques <>
SubjectRe: [PATCH] x86: Don't randomize stack unless current->personality permits it
Al Boldi wrote:
>[...] > void fn() {
>
> long i = 9999999;
> double x,y;
>
> elapsed(1);
> while (i--) fn2(&x,&y);
> printf("%4lu ",elapsed(0));
> }

You are not initializing x and y and with -Os at least my gcc really
uses floating point load/store operations to handle that code.

Maybe the coprocessor has a hard time normalizing certain garbage on the
stack, but without/with randomization the data comes from other
addresses and you're just lucky with the contents.

Does this also happens if you add a "x=0, y=0;" line to that function?

--
Paulo Marques - www.grupopie.com

Pointy-Haired Boss: I don't see anything that could stand in our way.
Dilbert: Sanity? Reality? The laws of physics?
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