[clang][extract-api] Refactor ExtractAPI and improve docs

- The name SymbolGraph is inappropriate and confusing for the new library
  for clang-extract-api. Refactor and rename things to make it clear that
  ExtractAPI is the core functionality and SymbolGraph is one serializer
  for the API information.
- Add documentation comments to ExtractAPI classes and methods to improve
  readability and clearness of the ExtractAPI work.

Differential Revision: https://reviews.llvm.org/D122160

1 files changed, 83 insertions, 0 deletions

diff --git a/clang/lib/ExtractAPI/API.cpp b/clang/lib/ExtractAPI/API.cpp
new file mode 100644
index 0000000..45eef3d
--- /dev/null
+++ b/clang/lib/ExtractAPI/API.cpp
@@ -0,0 +1,83 @@
+//===- ExtractAPI/API.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
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// This file implements the APIRecord and derived record structs,
+/// and the APISet class.
+///
+//===----------------------------------------------------------------------===//
+
+#include "clang/ExtractAPI/API.h"
+#include "clang/AST/CommentCommandTraits.h"
+#include "clang/AST/CommentLexer.h"
+#include "clang/AST/RawCommentList.h"
+#include "clang/Index/USRGeneration.h"
+#include "llvm/Support/Allocator.h"
+
+using namespace clang::extractapi;
+using namespace llvm;
+
+GlobalRecord *APISet::addGlobal(GVKind Kind, StringRef Name, StringRef USR,
+                                PresumedLoc Loc,
+                                const AvailabilityInfo &Availability,
+                                LinkageInfo Linkage, const DocComment &Comment,
+                                DeclarationFragments Fragments,
+                                DeclarationFragments SubHeading,
+                                FunctionSignature Signature) {
+  auto Result = Globals.insert({Name, nullptr});
+  if (Result.second) {
+    // Create the record if it does not already exist.
+    auto Record = APIRecordUniquePtr<GlobalRecord>(new (Allocator) GlobalRecord{
+        Kind, Name, USR, Loc, Availability, Linkage, Comment, Fragments,
+        SubHeading, Signature});
+    Result.first->second = std::move(Record);
+  }
+  return Result.first->second.get();
+}
+
+GlobalRecord *
+APISet::addGlobalVar(StringRef Name, StringRef USR, PresumedLoc Loc,
+                     const AvailabilityInfo &Availability, LinkageInfo Linkage,
+                     const DocComment &Comment, DeclarationFragments Fragments,
+                     DeclarationFragments SubHeading) {
+  return addGlobal(GVKind::Variable, Name, USR, Loc, Availability, Linkage,
+                   Comment, Fragments, SubHeading, {});
+}
+
+GlobalRecord *
+APISet::addFunction(StringRef Name, StringRef USR, PresumedLoc Loc,
+                    const AvailabilityInfo &Availability, LinkageInfo Linkage,
+                    const DocComment &Comment, DeclarationFragments Fragments,
+                    DeclarationFragments SubHeading,
+                    FunctionSignature Signature) {
+  return addGlobal(GVKind::Function, Name, USR, Loc, Availability, Linkage,
+                   Comment, Fragments, SubHeading, Signature);
+}
+
+StringRef APISet::recordUSR(const Decl *D) {
+  SmallString<128> USR;
+  index::generateUSRForDecl(D, USR);
+  return copyString(USR);
+}
+
+StringRef APISet::copyString(StringRef String) {
+  if (String.empty())
+    return {};
+
+  // No need to allocate memory and copy if the string has already been stored.
+  if (Allocator.identifyObject(String.data()))
+    return String;
+
+  void *Ptr = Allocator.Allocate(String.size(), 1);
+  memcpy(Ptr, String.data(), String.size());
+  return StringRef(reinterpret_cast<const char *>(Ptr), String.size());
+}
+
+APIRecord::~APIRecord() {}
+
+void GlobalRecord::anchor() {}