machine learning for loop unrolling

[Maxim Kuvyrkov]

Zdenek Dvorak wrote:

...

>> The number of parallel "computations" in loop.
>> The estimated latency of the critical path of loop.
>> The estimated cycle length of loop body.
>> The max. dependence height of computations.
>> The max. height of memory dependencies of computations.
>> The max. height of control dependencies of computations.
>> The average dependence height of computations.
>> The min. memory-to-memory loop-carried dependence.
>> The number of memory-to-memory dependencies.
> 
> This is a bit more difficult; I guess you could persuade scheduler to
> give you this information, but I have no idea how exactly.  See
> modulo-sched.c, it considers similar kind of information.

Stefan,

You can get a DDG for an acyclic graph (which one iteration of the loop 
is :) from sched-deps.c.  From that DDG it should not be difficult to 
compute properties you want.  If you want to get interloop properties, 
then take a look at ddg.c - modulo-sched.c uses it to build interloop 
dependencies.

--
Maxim