[PATCH v2 2/5] powerpc/lib/sstep: Add popcnt instruction emulation
Segher Boessenkool
segher at kernel.crashing.org
Mon Jul 24 17:36:55 AEST 2017
Hi Matt,
On Mon, Jul 24, 2017 at 11:01:06AM +1000, Matt Brown wrote:
> + for (i = 0; i < (64 / size); i++) {
If you do
for (i = 0; i < 64; i += size)
things are slightly nicer.
> + if ((i * size) < 32)
> + low |= n << (i * size);
> + else
> + high |= n << ((i * size) - 32);
> + }
> + regs->gpr[ra] = (high << 32) | low;
Why have separate high and low vars?
And there are much better ways to calculate popcount, of course.
Segher
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