question on inline assembly and long long values
benh at kernel.crashing.org
Thu Apr 7 09:57:03 EST 2005
On Wed, 2005-04-06 at 17:56 -0600, Chris Friesen wrote:
> Benjamin Herrenschmidt wrote:
> > But the kernel code always runs in 64 bits mode...
> The ppc kernel (not ppc64) runs in 64-bit mode? An unsigned long long
> fits in a single register in C code?
Ah no, it doesn't, but then, be careful to have interrupts off when you
do that are the interrupt handler won't save the high half of the
registers between the mtmsrd and your "splitting" of it.
> Yeah, the optimisations really don't matter much...the ugly resulting
> code just bothered me.
Benjamin Herrenschmidt <benh at kernel.crashing.org>
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