[PATCH] D146734: [CodeGen] Use RegUnits in RegisterClassInfo::getLastCalleeSavedAlias

[Jay Foad via Phabricator via llvm-commits]

foad added inline comments.


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Comment at: llvm/include/llvm/CodeGen/RegisterClassInfo.h:60
+  // Map regunit to the callee saved Register.
   SmallVector<MCPhysReg, 4> CalleeSavedAliases;
 
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arsenm wrote:
> SmallVector<4> seems like a weird way to map this. I'd expect all sets of registers to be BitVectors?
Not sure what you mean. We just want an array here, so we can lookup the CSR corresponding to a particular regunit as quickly as possible. (I agree the "4" is weird.)


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D146734/new/

https://reviews.llvm.org/D146734