[clang] [CIR][NEON] Add lowering for `vnegd_s64` and `vnegh_f16` (PR #180597)

[Andy Kaylor via cfe-commits]

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@@ -362,6 +362,20 @@ class CIRGenBuilderTy : public cir::CIRBaseBuilderTy {
     return getConstantInt(loc, getUInt64Ty(), c);
   }
 
+  /// Create constant nullptr for pointer-to-data-member type ty.
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andykaylor wrote:

We generally try to keep these kinds of cleanup-related changes in a separate NFC PR to keep the revision history clean, but I appreciate the improved organization.

https://github.com/llvm/llvm-project/pull/180597