[FFmpeg-devel] [Patch] beautified + accelerated vf_fillborders – Please review

[Ulf Zibis]

Am 24.03.19 um 00:40 schrieb Carl Eugen Hoyos:
> There are two patches "1", one with wrong indentation.
I intentionally have provided 2 patches with the same number, one for
the code base an one with additions for the benchmark. I've catched the
wrong indentation, hopefully at the place you meant.

> Iiuc, the patch mixes the following:
> Renaming of a variable
> Moving of blocks
> Adding commented code that is removed in a later patch
> Replacing constants with harder to read calculations
This is an argument. There are several places in the code using "* 2".
At some places this is an algorithmic purpose, at others to serve the
16-bit logic. I wanted to set this in clear view.

> Adding comments
>
> I don't maintain the file but in general not all of these are
> acceptable and it any case should be separate changes.
>
> This also removes outcommented code which should
> not be part of a performance enhancement.
> How much "slight enhancement" were you able to measure?
> Iiuc, some cases get slower, no?
> Some people prefer that patches like this do not change the
> indentation to make it more readable.
>
> Again: Please do not mix functional and cosmetic changes.
I'm preparing a new set of patches to follow your advice.

> Do I read the results correctly that for all patches some cases
> get faster and others get slower?

Correct. I'm wondering about the cases, where it gets such slower. So
I'm interested in an answer from you experienced developers to
understand this. Maybe a compiler option would help.

-Ulf