[Pixman] [PATCH 0/3] Composite args in stack allocated struct

[Søren Sandmann]

>> I'm actually all for this change if it gets confirmed to work a bit
>> better and faster (and I expect that it should, considering that all
>> this data can be passed through some nested calls multiple
>> times). Hopefully we are not running in circles.
>
> The FbComposeData struct was used in precisely one place to pass
> information between two functions. It could not possibly have provided
> any benefit as it existed in X server 1.3, which is the version that
> eventually became pixman.
>
> I think what might have happened is that full support for FbComposeData
> was introduced in one of the several forks that existed around 2005 and
> never merged into Xorg, except for that one place. 
>
> So I'm not too worried about running in circles, but I don't know if it
> is actually a performance advantage. I tend to think that if such
> microoptimizations really result in measurable performance advantage,
> then then the problem should probably be fixed in some other way.

The following emails contain a rebased version of this branch against
master.

 pixman/pixman-arm-common.h     |   82 +-----
 pixman/pixman-arm-neon.c       |   16 -
 pixman/pixman-compiler.h       |    6 
 pixman/pixman-fast-path.c      |  436 +++++++-----------------------------
 pixman/pixman-fast-path.h      |   38 ---
 pixman/pixman-general.c        |   45 +--
 pixman/pixman-implementation.c |   12 -
 pixman/pixman-mmx.c            |  373 +++++++------------------------
 pixman/pixman-noop.c           |   15 -
 pixman/pixman-private.h        |   51 ++--
 pixman/pixman-sse2.c           |  486 +++++++++--------------------------------
 pixman/pixman.c                |   68 +++--
 pixman/pixman.h                |    6 
 test/lowlevel-blt-bench.c      |   84 ++++---
 14 files changed, 482 insertions(+), 1236 deletions(-)


Soren