graphite in -O3

Richard Biener
Mon Nov 17 13:13:00 GMT 2014

On Sun, Nov 16, 2014 at 10:08 PM, David Edelsohn <> wrote:
> Because they have not shown general performance benefit.

Also they very often cause very long compile-times.

> I hope that the renewed attention and development effort will allow
> them to be enabled by default eventually.

Yeah - though I'd like to have a group flag that enables the mature
ones.  Mature here means transforms that guard themselves properly
for long compile-time and ones that have a cost model (may be
a runtime check even).


> Thanks, David
> On Sun, Nov 16, 2014 at 2:10 PM, Andi Kleen <> wrote:
>> Is there any specific reason why none of the graphite loop optimizations
>> (loop-block, loop-interchange, loop-strip-mine, loop-jam)
>> are enabled with -O3 or -Ofast?
>> I assume doing so would make them much more widely used.
>> Perhaps would be something to consider for 5.0?
>> -Andi

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