Re: Image scaling performance

[Michael Zimmermann]

oh ok so linux's div/mod/... assembler is as slow/fast as grub's code?
Linux uses armv5>= ifdefs. Maybe we could optimized things a little :)
About scale_nn,
amarullz(https://plus.google.com/u/0/+AhmadAmarullah/about) wrote a
optimized version without divs:
loops: http://pastebin.com/MaZqWSA9
memcpy: http://pastebin.com/iNq0V5Tw

this code works a little faster. I'm still questioning the efficiency
math operations because on slow devices there are other bottlenecks of
the same kind(like de/compression).

On Wed, Feb 25, 2015 at 7:41 PM, Vladimir 'phcoder' Serbinenko
<address@hidden> wrote:
> ARMv7 doesn't mandate div instructions. It's a separate flag in features.
> GRUB supports earlier CPUs as well and we use them for testing. My only test
> machine is armv6
>
> Le 2015-02-25 19:38, "Michael Zimmermann" <address@hidden> a écrit
> :
>
>> Why u think the native div code would crash on most devices? I support
>> ARMv7+ only anyway.
>>
>> On Wed, Feb 25, 2015 at 5:23 PM, Leif Lindholm <address@hidden>
>> wrote:
>> > On Wed, Feb 25, 2015 at 03:45:40PM +0000, Leif Lindholm wrote:
>> >> > >> Some technical info:
>> >> > >> ARMv7
>> >> > >> Linaro GCC 4.9
>> >>
>> >> I don't see any calls to any of the __aeabi helpers generated for this
>> >> file with current head. Which specific Linaro toolchain are you using?
>> >> (mine is"Linaro GCC 4.9-2014.09").
>> >
>> > Scratch that, I do see them. Just failing to drive the tools properly.
>> >
>> > /
>> >     Leif
>> >
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