[llvm] [NFC][TableGen][GlobalISel] Move MIR Pattern Parsing out of Combiner Impl (PR #80257)

[Pierre van Houtryve via llvm-commits]

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@@ -0,0 +1,462 @@
+//===- PatternParser.cpp ----------------------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "PatternParser.h"
+#include "../CodeGenIntrinsics.h"
+#include "../CodeGenTarget.h"
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Pierre-vh wrote:

They're not avoidable here, `Pattern.cpp` also needs them

https://github.com/llvm/llvm-project/pull/80257