[PATCH 1/2] s/390: Implement "target" attribute.

Andreas Krebbel krebbel@linux.vnet.ibm.com
Mon Nov 9 07:10:00 GMT 2015


On 10/31/2015 06:58 PM, Dominik Vogt wrote:
> But what the heck is this "exact power of 2" limitation good for
> in the first place?  Why is a stack size of 1, 2 or
> 36028797018963968 valid, but not 800?  Shouldn't the stack size
> (and the size of the stack guard) just be multiples of the stack
> slot size?

That's because of the way we implement the stack check.  We use test under mask to check for certain
bits instead of doing the full math and compare.

-Andreas-




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