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Re: Default value of x87 registers' reserved bits



On Sun, May 30, 2010 at 06:28:27PM +1000, Giles Lean wrote:
> It would be _especially_ nasty if the reserved bits could change, say,
> in a trap handler: then you could have a race between fetching the bits,
> making your desired changes to the unreserved bits, and writing them
> back.

Oh, that's not _especially_ nasty.  _Especially_ nasty is having the bits
always read the same way but have persistent effect on write.

Thor


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