wheezy libc optimisation - Raspberry Pi Forums

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hi,

new forum, although i've had rpi b(-) years now. thinking how breeze new speed `black box'. not skillful in programming nor talented on uelectronics, proud have fitted reset switch board, push button facing through hole of rpi case.

have set `turbo' mode time ago, thinking of optimisations. have done coding in assembly on `sinclair ql', powerpc chip, far no knowledge of arm processors here.

thinking along these lines.
remember `ppc' able commit several instructions in single cycle, through mechanism of pipelining , out of order dispatching. unrolled loops, copy memory blocks 4-6 times faster on same processor speed.

remembering `atari st' blitter chip, not use copy graphics, move other memory blocks around.

processor in 90% of time copy move data around, hoping speed performance benefit optimising copy move blocks functions possibly in `libc' library, of calls end up.

not sure if above make @ sense, might not capable doing optimisations myself. curious how works arm code.

many thanks.
tom

this has been done (it in 2013 or so) :

https://raspberrypi.stackexchange.com/q ... libcofi-do
https://github.com/simonjhall/copies-and-fills/

ghans


raspberrypi



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