[Intel-gfx] [PATCH] sna: Fix comment on GCC version check

[Sedat Dilek]

On Wed, Feb 27, 2013 at 11:27 PM, Chris Wilson <chris at chris-wilson.co.uk> wrote:
> On Wed, Feb 27, 2013 at 06:59:58PM +0100, Sedat Dilek wrote:
>> How can I compare a gcc-4.6 and clang-3.2 compiled binaries?
>> Thinking of miscompiling and/or benchmarking.
>
> The real test is whether you can measure a difference in a benchmark
> like cairo-perf-trace. There are a few traces that are sensitive to CPU
> optimisations.
>
> To maximise the likelihood of spotting a difference though you will want
> to use microbenchmarks like x11perf, x11perf -aa10text would be a prime
> candidate.
>
> The last set of errors reported when compiled with Clang were during
> trapezoid rasterisation triggered whilst using normal Gtk+ and Qt apps.
> They have a tendency to hit all the corner cases.
> -Chris
>
> --
> Chris Wilson, Intel Open Source Technology Centre

Attached 'x11perf -aa10text' with clang-3.2 and gcc-4.6.

- Sedat .
-------------- next part --------------
$ x11perf -aa10text
x11perf - X11 performance program, version 1.2
The X.Org Foundation server version 11103000 on :0
from fambox
Thu Feb 28 00:25:23 2013

Sync time adjustment is 0.0446 msecs.

6400000 reps @   0.0008 msec (1240000.0/sec): Char in 80-char aa line (Charter 10)
6400000 reps @   0.0008 msec (1240000.0/sec): Char in 80-char aa line (Charter 10)
6400000 reps @   0.0008 msec (1240000.0/sec): Char in 80-char aa line (Charter 10)
6400000 reps @   0.0008 msec (1240000.0/sec): Char in 80-char aa line (Charter 10)
6400000 reps @   0.0008 msec (1240000.0/sec): Char in 80-char aa line (Charter 10)
32000000 trep @   0.0008 msec (1240000.0/sec): Char in 80-char aa line (Charter 10)


-dileks // 28-Feb-2013
-------------- next part --------------
$ x11perf -aa10text
x11perf - X11 performance program, version 1.2
The X.Org Foundation server version 11103000 on :1
from fambox
Thu Feb 28 00:29:02 2013

Sync time adjustment is 0.0390 msecs.

16000000 reps @   0.0005 msec (2110000.0/sec): Char in 80-char aa line (Charter 10)
16000000 reps @   0.0005 msec (2120000.0/sec): Char in 80-char aa line (Charter 10)
16000000 reps @   0.0005 msec (2110000.0/sec): Char in 80-char aa line (Charter 10)
16000000 reps @   0.0005 msec (2010000.0/sec): Char in 80-char aa line (Charter 10)
16000000 reps @   0.0005 msec (2050000.0/sec): Char in 80-char aa line (Charter 10)
80000000 trep @   0.0005 msec (2080000.0/sec): Char in 80-char aa line (Charter 10)


-dileks // 28-Feb-2013