[Pixman] [PATCH] fill: Special-case single pixel wide lines
sandmann at cs.au.dk
Fri Sep 23 01:37:02 PDT 2011
Chris Wilson <chris at chris-wilson.co.uk> writes:
> A common condition (in benchmarks at least) are single pixel wide
> vertical lines. This is the worst-cast behaviour for the fast-paths like
> SSE2 which require long runs in order to offset the ramp up cost of
> aligning and using the SIMD registers.
> For example, box-outline consists of drawing a single aligned box with a
> hairline outline:
> before: 2327 (stroke), 2509 (fill)
> after: 674 (stroke), 843 (fill)
> [measured in *ns* on an i7-640]
> (Double-pixel wide lines, such as a stroke-width 1 outline of a
> misaligned box are also very common, but cannot hit pixman_fill(), so
> rapidly diminishing returns for optimising other widths.)
Looks good to me.
Generally, if nobody has said anything for some reasonable length of
time, feel free to push.
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