[llvm] AMDGPU/GlobalISel: add RegBankLegalize rules for bitfield extract (PR #132381)

[Nicolai Hähnle via llvm-commits]

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@@ -225,6 +228,103 @@ void RegBankLegalizeHelper::lower(MachineInstr &MI,
     MI.eraseFromParent();
     break;
   }
+  case Div_BFE: {
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nhaehnle wrote:

Yes, that makes sense.

Actually, this could be a motivation for being able to directly specify a helper function to be used as part of the legalizer rule definition...

https://github.com/llvm/llvm-project/pull/132381