[PATCH] D126771: [fastalloc] Support allocate specific register class in fastalloc.

[LuoYuanke via Phabricator via llvm-commits]

LuoYuanke added inline comments.


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Comment at: llvm/lib/CodeGen/RegAllocFast.cpp:1164
       } else if (Reg.isPhysical()) {
         if (!MRI->isReserved(Reg)) {
           if (MO.isDef()) {
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xiangzhangllvm wrote:
> Are you handling here too ?
> Here when we allocating tile registers (we don't want allocation/handle other non-tile registers). But the logic here is possible to handle other non-tile registers, for example we may reload for non-tile registers in definePhysReg.
> This may not has correction problem, but it is very strange to handle the non-tile registers in tile register fast allocation. And even in non-AMX program, the problem still existed. 
For physical register it is not filtered. I think the pass won't do anything for physical registers given there is no virtual register for the corresponding register class.


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https://reviews.llvm.org/D126771