Displaying 3 results from an estimated 3 matches for "hasloopzerocosttopolog".
Did you mean:
hasloopzerocosttopology
2012 Nov 23
1
[LLVMdev] Disable loop unroll pass
...HW-loop conflict with unrolling
etc. So optimizer
has no idea how to use this interface. If you just call
this interface to disable
unrolling, that would be overkill on some arch which has HW
support, as
on such arch HW-loop and unrolling are orthogonal.
- hasLoopZeroCostTopology(Loop *L, unsigend TripCount)
Why trip-count? It can be derived from the loop itself.
Which optimizer will call this interface?
I would suggest following interface:
/// get unrolling factor of given *INNERMOST* loop from HW's
perspective.
/// Note: this interface is...
2012 Nov 23
0
[LLVMdev] Disable loop unroll pass
...rator, which doesn't make things any simpler.
I think we are going off-topic. I'm not proposing new llvm instructions
to introduce hw loop semantics. What I'd like to do is to find a good
interface between the loop unroller and targets to prevent loop unrolling.
hasZeroCostLoop() and hasLoopZeroCostTopology(Loop *L, unsigend
TripCount) has been proposed so far.
Ivan
>
> Thanks
> Shuxin
>
> On 11/22/2012 02:56 PM, Gang Yu wrote:
>> Hi shuxin,
>>
>> Promote while-loop to do-loop is the job of loop induction
>> recognized, not this transformation. The scalar tr...
2012 Nov 22
2
[LLVMdev] Disable loop unroll pass
Hi, Gang:
I don't want to discuss Open64 internal in LLVM mailing list. Let us
only focus on the design per se.
As your this mail and your previous mail combined give me a impression
that :
The only reason you introduce the specific operator for HW loop in
Scalar Opt simply because
you have hard time in figure out the trip count in CodeGen.
This might be true for Open64's