[LLVMdev] Custom constraints in instruction schedulers

[Dave Estes]

On 11/07/2014 04:54 AM, Sergey Dmitrouk wrote:
> What I'm trying to do
> ---------------------
>
> Ensuring that ldp-stp instruction pair used to implement inlined memcpy()
> have no instructions between them.
Hey Sergey,

I only learned of clustering a short time ago, but it sounds like what 
you're after. The MIScheduler uses clusters as one of the heuristics. 
The idea is to ensure that instructions remain clustered (if possible) 
after scheduling to ensure later peephole optimizations still work. I 
haven't used it, so I can't speak to the effectiveness. Hope this helps.

-Dave

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