[LLVMdev] Questions about MachineScheduler

[Tom Stellard]

Hi,

I'm working on defining a SchedMachineModel for the Southern Islands
family of GPUs, and I have two questions related to the
MachineScheduler.

1. I have a resource that can process 15 instructions at the same time.
In the TableGen definitions, should I do:

def HWVMEM   : ProcResource<15>;

or

let BufferSize = 15 in {
def HWVMEM : ProcResource<1>;
}

2. Southern Islands has 256 registers, but there is a significant
performance penalty if you use more than a certain amount.  Do any of
the MachineSchedulers support switching into an 'optimize for register
pressure mode' once it detects register pressure above a certain limit?

Thanks,
Tom