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Re: [PATCH 19/26] arm: Add optimized ffs for armv6t2
On 02/27/2013 07:51 AM, Måns Rullgård wrote:
> Richard Henderson <email@example.com> writes:
>> + cmp r0, #0
>> + ittt ne
>> + rbitne r0, r0
>> + clzne r0, r0
>> + addne r0, r0, #1
>> + bx lr
> Making the RBIT unconditional (bit-reverse of zero is still zero) is
> better since it reduces dependencies between instructions. Depending on
> microarchitecture details, this might save a cycle.
Fair enough. Consider this change made for any next round.