[Mesa-dev] [PATCH] glsl: Optimize certain if-statements to just casts from the condition

[Ian Romanick]

On 01/16/2015 04:25 PM, Matt Turner wrote:
> On Thu, Jan 15, 2015 at 6:46 PM, Ian Romanick <idr at freedesktop.org> wrote:
>> On 01/16/2015 08:15 AM, Matt Turner wrote:
>>> From: Ian Romanick <ian.d.romanick at intel.com>
>>>
>>> Some shaders end up with code that looks something like:
>>>
>>>     if (some_condition)
>>>         result = 1.0;
>>>     else
>>>         result = 0.0;
>>>
>>> This pass converts those if-statements to
>>>
>>>      result = float(some_condition);
>>>
>>> total instructions in shared programs: 5934568 -> 5921818 (-0.21%)
>>> instructions in affected programs:     723433 -> 710683 (-1.76%)
>>> GAINED:                                26
>>> LOST:                                  7
>>
>> I was getting really different results here... on my more recent version
>> (that should produce the same IR), I was getting basically the reverse
>> lost / gained.  The other results were about the same.
>>
>> I updated both Mesa and shader-db, and I'm not able to do a full
>> shader-db run now.  At semi-arbitrary points in the run I get
>>
>> Exception: Only shader 0 found.
>> shaders/closed/unreal4/sun-temple/180.shader_test
> 
> You need commit f0aec4ee1e3 to avoid an assertion failure.
> 
>> If I run that shader_test by hand, I get multiple shader emitted.  I'm
>> using the older run.py... is it possible that's broken?
> 
> It's been working for me in occasional usage to generate *.out files.

Trivial. :p

diff --git a/run.py b/run.py
index 4fc366e..d57da21 100755
--- a/run.py
+++ b/run.py
@@ -57,7 +57,7 @@ def run_test(filename):
         raise Exception('Only shader 0 found. {}'.format(filename))
 
     re_search = re.compile(
-        r'(?P<stage>[A-Za-z0-9]+) shader\: (?P<count>\d+) instructions.')
+        r'(?P<stage>[A-Za-z0-9 ]+) shader\: (?P<count>\d+) instructions.')
     for line in lines:
         match = re_search.match(line)
         if match is not None: