[clang] [CIR] Lower __builtin_bswapg (PR #203618)

[Andy Kaylor via cfe-commits]

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@@ -1277,6 +1277,21 @@ RValue CIRGenFunction::emitBuiltinExpr(const GlobalDecl &gd, unsigned builtinID,
     return RValue::get(cir::ByteSwapOp::create(builder, loc, arg));
   }
 
+  case Builtin::BI__builtin_bswapg: {
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andykaylor wrote:

Can you move this above BI__builtin_bswap16 to keep the ordering consistent with classic codegen?

https://github.com/llvm/llvm-project/pull/203618