[clang] [CIR] Add X86 prefetch builtins (PR #168051)

[Andy Kaylor via cfe-commits]

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@@ -1272,9 +1272,6 @@ RValue CIRGenFunction::emitBuiltinExpr(const GlobalDecl &gd, unsigned builtinID,
     llvm_unreachable("Bad evaluation kind in EmitBuiltinExpr");
   }
 
-  cgm.errorNYI(e->getSourceRange(),
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andykaylor wrote:

What about `__builtin_constant_p`? This was also handling missing builtins that are not target-specific?

https://github.com/llvm/llvm-project/pull/168051