[clang] [CIR] Upstream CIR codegen for align x86 builtins (PR #173788)

[Amr Hesham via cfe-commits]

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@@ -1695,7 +1730,7 @@ CIRGenFunction::emitX86BuiltinExpr(unsigned builtinID, const CallExpr *expr) {
     cgm.errorNYI(expr->getSourceRange(),
                  std::string("unimplemented X86 builtin call: ") +
                      getContext().BuiltinInfo.getName(builtinID));
-    return {};
+    return mlir::Value{};
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AmrDeveloper wrote:

Is there a reason for this change? from `{}` to `mlir::Value{}`

https://github.com/llvm/llvm-project/pull/173788