[clang] [CIR] Add cir-opt tool to exercise CIR dialect parsing (PR #128254)

[Andy Kaylor via cfe-commits]

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@@ -0,0 +1,19 @@
+#ifndef CLANG_CIR_PASSES_H
+#define CLANG_CIR_PASSES_H
+
+#include "mlir/Pass/Pass.h"
+
+#include <memory>
+
+namespace cir {
+namespace direct {
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andykaylor wrote:

There will eventually be things in this file that are in the cir namespace, but not in the cir::direct namespace, so I'd prefer to keep it separate.

https://github.com/llvm/llvm-project/pull/128254