[PATCH] D86253: [AMDGPU] Disable stall weight calculation in regbank-reassign

[Stanislav Mekhanoshin via Phabricator via llvm-commits]

rampitec added inline comments.


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Comment at: llvm/lib/Target/AMDGPU/GCNRegBankReassign.cpp:605
       unsigned Weight = getOperandGatherWeight(MI, Reg1, Reg2, StallCycles);
       Weight += MLI->getLoopDepth(MI.getParent()) * 10;
 
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rampitec wrote:
> critson wrote:
> > Presumably we don't need to do this if we are not using weights at all (i.e. no sorting)?
> > Perhaps "if (UseWeight)" all of this?
> Good point. It is cheap, but still.
Actually since it is cheap it makes sense to keep loop depth weight. The operand forwarding part is expensive, but the sort is not. I will experiment tomorrow and return sort and MLI part, just disable operand scan part.


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  https://reviews.llvm.org/D86253/new/

https://reviews.llvm.org/D86253