[FFmpeg-devel] [PATCH 2/2] swscale/input: Avoid calls to av_pix_fmt_desc_get()

[Michael Niedermayer]

Hi

On Thu, Sep 08, 2022 at 04:38:11AM +0200, Andreas Rheinhardt wrote:
> Up until now, libswscale/input.c used a macro to read
> an input pixel which involved a call to av_pix_fmt_desc_get()
> to find out whether the input pixel format is BE or LE
> despite this being known at compile-time (there are templates
> per pixfmt). Even worse, these calls are made in a loop,
> so that e.g. there are six calls to av_pix_fmt_desc_get()
> for every pair of UV pixel processed in
> rgb64ToUV_half_c_template().
> 
> This commit modifies these macros to ensure that isBE()
> is evaluated at compile-time. This saved 9743B of .text
> for me (GCC 11.2, -O3).

hmm, all these functions where supposed to be optimized out
why where they not ?

iam asking as the code is simpler before your patch if that
"optimization out" thing would work

thx

[...]
-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

Everything should be made as simple as possible, but not simpler.
-- Albert Einstein
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