[clang] [NFC][CodeGen] Create method to clear registers (PR #66958)

[Nick Desaulniers via cfe-commits]

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@@ -8335,6 +8335,26 @@ bool AArch64InstrInfo::shouldOutlineFromFunctionByDefault(
   return MF.getFunction().hasMinSize();
 }
 
+void AArch64InstrInfo::buildClearRegister(Register Reg, MachineBasicBlock &MBB,
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nickdesaulniers wrote:

Ah! Ok, they *why* for this PR was not clear to me.

https://github.com/llvm/llvm-project/pull/66958