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SubjectRe: [patch 2/3] ipc: use shifts to extract seq/idx
On 05/20/2010 09:00 AM, Nick Piggin wrote:
> All the ipc ids and sequences are signed integers, so power of 2
> sequence multiplier does not work so well. Convert it to use shifts,
> which improves generated code particularly in ipc_lock/ipc_lock_check
> fast paths.
Have you checked the asm output?
I would expect that gcc auto-optimizes constant divides by power-of-two.


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