[clang] [clang][ExtractAPI] Add ability to create multiple symbol graphs (PR #86676)

[via cfe-commits]

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@@ -0,0 +1,169 @@
+//===- ExtractAPI/Serialization/APISetVisitor.h ----------------*- 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
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// This file defines the ExtractAPI APISetVisitor interface.
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_EXTRACTAPI_SERIALIZATION_SERIALIZERBASE_H
+#define LLVM_CLANG_EXTRACTAPI_SERIALIZATION_SERIALIZERBASE_H
+
+#include "clang/ExtractAPI/API.h"
+
+namespace clang {
+namespace extractapi {
+
+// A helper macro to implement short-circuiting when recursing.  It
+// invokes CALL_EXPR, which must be a method call, on the derived
+// object (s.t. a user of RecursiveASTVisitor can override the method
+// in CALL_EXPR).
+#define TRY_TO(CALL_EXPR)                                                      \
+  do {                                                                         \
+    if (!getDerived()->CALL_EXPR)                                              \
+      return false;                                                            \
+  } while (false)
+
+/// The base interface of visitors for API information, the interface and usage
+/// is almost identical to RecurisveASTVistor. This class performs three
+/// distinct tasks:
+/// 1. traverse the APISet (i.e. go to every record);
+/// 2. at a given record, walk up the class hierarchy starting from the record's
+/// dynamic type until APIRecord is reached.
+/// 3. given a (record, class) combination where 'class' is some base class of
+/// the dynamic type of 'node', call a user-overridable function to actually
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QuietMisdreavus wrote:

Should this `'node'` here actually say `'record'`?

https://github.com/llvm/llvm-project/pull/86676