[llvm] [BPF] Allow libcalls behind a feature gate (PR #168442)

[Matt Arsenault via llvm-commits]

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@@ -1196,3 +1198,18 @@ bool BPFTargetLowering::isLegalAddressingMode(const DataLayout &DL,
 
   return true;
 }
+
+bool BPFTargetLowering::shouldSignExtendTypeInLibCall(Type *Ty,
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arsenm wrote:

This is a separate change 

https://github.com/llvm/llvm-project/pull/168442