Avoid SourceManager.h include in RawCommentList.h, add missing incs

SourceManager.h includes FileManager.h, which is expensive due to
dependencies on LLVM FS headers.

Remove dead BeforeThanCompare specialization.

Sink ASTContext::addComment to cpp file.

This reduces the time to compile a file that does nothing but include
ASTContext.h from ~3.4s to ~2.8s for me.

Saves these includes:
    219 -    ../clang/include/clang/Basic/SourceManager.h
    204 -    ../clang/include/clang/Basic/FileSystemOptions.h
    204 -    ../clang/include/clang/Basic/FileManager.h
    165 -    ../llvm/include/llvm/Support/VirtualFileSystem.h
    164 -    ../llvm/include/llvm/Support/SourceMgr.h
    164 -    ../llvm/include/llvm/Support/SMLoc.h
    161 -    ../llvm/include/llvm/Support/Path.h
    141 -    ../llvm/include/llvm/ADT/BitVector.h
    128 -    ../llvm/include/llvm/Support/MemoryBuffer.h
    124 -    ../llvm/include/llvm/Support/FileSystem.h
    124 -    ../llvm/include/llvm/Support/Chrono.h
    124 -    .../MSVCSTL/include/stack
    122 -    ../llvm/include/llvm-c/Types.h
    122 -    ../llvm/include/llvm/Support/NativeFormatting.h
    122 -    ../llvm/include/llvm/Support/FormatProviders.h
    122 -    ../llvm/include/llvm/Support/CBindingWrapping.h
    122 -    .../MSVCSTL/include/xtimec.h
    122 -    .../MSVCSTL/include/ratio
    122 -    .../MSVCSTL/include/chrono
    121 -    ../llvm/include/llvm/Support/FormatVariadicDetails.h
    118 -    ../llvm/include/llvm/Support/MD5.h
    109 -    .../MSVCSTL/include/deque
    105 -    ../llvm/include/llvm/Support/Host.h
    105 -    ../llvm/include/llvm/Support/Endian.h

Reviewed By: aaron.ballman, hans

Differential Revision: https://reviews.llvm.org/D75279
diff --git a/clang/include/clang/AST/ASTContext.h b/clang/include/clang/AST/ASTContext.h
index c944e09..2640c66 100644
--- a/clang/include/clang/AST/ASTContext.h
+++ b/clang/include/clang/AST/ASTContext.h
@@ -721,15 +721,7 @@
   RawComment *getRawCommentForDeclNoCache(const Decl *D) const;
 
 public:
-  RawCommentList &getRawCommentList() {
-    return Comments;
-  }
-
-  void addComment(const RawComment &RC) {
-    assert(LangOpts.RetainCommentsFromSystemHeaders ||
-           !SourceMgr.isInSystemHeader(RC.getSourceRange().getBegin()));
-    Comments.addComment(RC, LangOpts.CommentOpts, BumpAlloc);
-  }
+  void addComment(const RawComment &RC);
 
   /// Return the documentation comment attached to a given declaration.
   /// Returns nullptr if no comment is attached.
diff --git a/clang/include/clang/AST/ASTDumper.h b/clang/include/clang/AST/ASTDumper.h
index 61202f0..f46ffb9 100644
--- a/clang/include/clang/AST/ASTDumper.h
+++ b/clang/include/clang/AST/ASTDumper.h
@@ -11,6 +11,7 @@
 
 #include "clang/AST/ASTNodeTraverser.h"
 #include "clang/AST/TextNodeDumper.h"
+#include "clang/Basic/SourceManager.h"
 
 namespace clang {
 
diff --git a/clang/include/clang/AST/RawCommentList.h b/clang/include/clang/AST/RawCommentList.h
index 1eea56d..a18432c 100644
--- a/clang/include/clang/AST/RawCommentList.h
+++ b/clang/include/clang/AST/RawCommentList.h
@@ -11,9 +11,9 @@
 
 #include "clang/Basic/CommentOptions.h"
 #include "clang/Basic/SourceLocation.h"
-#include "clang/Basic/SourceManager.h"
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/DenseMap.h"
+#include "llvm/Support/Allocator.h"
 #include <map>
 
 namespace clang {
@@ -21,7 +21,9 @@
 class ASTContext;
 class ASTReader;
 class Decl;
+class DiagnosticsEngine;
 class Preprocessor;
+class SourceManager;
 
 namespace comments {
   class FullComment;
@@ -173,23 +175,6 @@
   friend class ASTReader;
 };
 
-/// Compare comments' source locations.
-template<>
-class BeforeThanCompare<RawComment> {
-  const SourceManager &SM;
-
-public:
-  explicit BeforeThanCompare(const SourceManager &SM) : SM(SM) { }
-
-  bool operator()(const RawComment &LHS, const RawComment &RHS) {
-    return SM.isBeforeInTranslationUnit(LHS.getBeginLoc(), RHS.getBeginLoc());
-  }
-
-  bool operator()(const RawComment *LHS, const RawComment *RHS) {
-    return operator()(*LHS, *RHS);
-  }
-};
-
 /// This class represents all comments included in the translation unit,
 /// sorted in order of appearance in the translation unit.
 class RawCommentList {
diff --git a/clang/lib/ARCMigrate/TransProtectedScope.cpp b/clang/lib/ARCMigrate/TransProtectedScope.cpp
index 9e9e9cb..154e0b5 100644
--- a/clang/lib/ARCMigrate/TransProtectedScope.cpp
+++ b/clang/lib/ARCMigrate/TransProtectedScope.cpp
@@ -11,9 +11,10 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include "Transforms.h"
 #include "Internals.h"
+#include "Transforms.h"
 #include "clang/AST/ASTContext.h"
+#include "clang/Basic/SourceManager.h"
 #include "clang/Sema/SemaDiagnostic.h"
 
 using namespace clang;
diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index b4527dc..b816f3b 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -296,6 +296,12 @@
   return getRawCommentForDeclNoCacheImpl(D, DeclLoc, *CommentsInThisFile);
 }
 
+void ASTContext::addComment(const RawComment &RC) {
+  assert(LangOpts.RetainCommentsFromSystemHeaders ||
+         !SourceMgr.isInSystemHeader(RC.getSourceRange().getBegin()));
+  Comments.addComment(RC, LangOpts.CommentOpts, BumpAlloc);
+}
+
 /// If we have a 'templated' declaration for a template, adjust 'D' to
 /// refer to the actual template.
 /// If we have an implicit instantiation, adjust 'D' to refer to template.
diff --git a/clang/lib/AST/DataCollection.cpp b/clang/lib/AST/DataCollection.cpp
index 8e67c10..d3f2c22 100644
--- a/clang/lib/AST/DataCollection.cpp
+++ b/clang/lib/AST/DataCollection.cpp
@@ -7,7 +7,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "clang/AST/DataCollection.h"
-
+#include "clang/Basic/SourceManager.h"
 #include "clang/Lex/Lexer.h"
 
 namespace clang {
diff --git a/clang/lib/AST/ExternalASTSource.cpp b/clang/lib/AST/ExternalASTSource.cpp
index aa896aa..29ddc67 100644
--- a/clang/lib/AST/ExternalASTSource.cpp
+++ b/clang/lib/AST/ExternalASTSource.cpp
@@ -18,6 +18,7 @@
 #include "clang/Basic/IdentifierTable.h"
 #include "clang/Basic/LLVM.h"
 #include "clang/Basic/Module.h"
+#include "clang/Basic/SourceManager.h"
 #include "llvm/ADT/None.h"
 #include "llvm/Support/ErrorHandling.h"
 #include <cstdint>
diff --git a/clang/lib/AST/JSONNodeDumper.cpp b/clang/lib/AST/JSONNodeDumper.cpp
index 637b61e..bae5566 100644
--- a/clang/lib/AST/JSONNodeDumper.cpp
+++ b/clang/lib/AST/JSONNodeDumper.cpp
@@ -1,4 +1,5 @@
 #include "clang/AST/JSONNodeDumper.h"
+#include "clang/Basic/SourceManager.h"
 #include "clang/Lex/Lexer.h"
 #include "llvm/ADT/StringSwitch.h"
 
diff --git a/clang/lib/AST/MicrosoftMangle.cpp b/clang/lib/AST/MicrosoftMangle.cpp
index fa84716..5ed2586 100644
--- a/clang/lib/AST/MicrosoftMangle.cpp
+++ b/clang/lib/AST/MicrosoftMangle.cpp
@@ -10,7 +10,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include "clang/AST/Mangle.h"
 #include "clang/AST/ASTContext.h"
 #include "clang/AST/Attr.h"
 #include "clang/AST/CXXInheritance.h"
@@ -22,9 +21,11 @@
 #include "clang/AST/DeclTemplate.h"
 #include "clang/AST/Expr.h"
 #include "clang/AST/ExprCXX.h"
+#include "clang/AST/Mangle.h"
 #include "clang/AST/VTableBuilder.h"
 #include "clang/Basic/ABI.h"
 #include "clang/Basic/DiagnosticOptions.h"
+#include "clang/Basic/SourceManager.h"
 #include "clang/Basic/TargetInfo.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/Support/CRC.h"
diff --git a/clang/lib/AST/RawCommentList.cpp b/clang/lib/AST/RawCommentList.cpp
index 83e8a0b..8552b4f 100644
--- a/clang/lib/AST/RawCommentList.cpp
+++ b/clang/lib/AST/RawCommentList.cpp
@@ -16,6 +16,7 @@
 #include "clang/AST/CommentSema.h"
 #include "clang/Basic/CharInfo.h"
 #include "llvm/ADT/STLExtras.h"
+#include "llvm/Support/Allocator.h"
 
 using namespace clang;
 
diff --git a/clang/lib/AST/TextNodeDumper.cpp b/clang/lib/AST/TextNodeDumper.cpp
index c9b5718..9ed2829 100644
--- a/clang/lib/AST/TextNodeDumper.cpp
+++ b/clang/lib/AST/TextNodeDumper.cpp
@@ -15,6 +15,7 @@
 #include "clang/AST/DeclOpenMP.h"
 #include "clang/AST/DeclTemplate.h"
 #include "clang/AST/LocInfoType.h"
+#include "clang/Basic/SourceManager.h"
 
 using namespace clang;
 
diff --git a/clang/lib/Analysis/CloneDetection.cpp b/clang/lib/Analysis/CloneDetection.cpp
index 5fb5840..0a1122b 100644
--- a/clang/lib/Analysis/CloneDetection.cpp
+++ b/clang/lib/Analysis/CloneDetection.cpp
@@ -14,6 +14,7 @@
 #include "clang/AST/Attr.h"
 #include "clang/AST/DataCollection.h"
 #include "clang/AST/DeclTemplate.h"
+#include "clang/Basic/SourceManager.h"
 #include "llvm/Support/MD5.h"
 #include "llvm/Support/Path.h"
 
diff --git a/clang/lib/CodeGen/CGExpr.cpp b/clang/lib/CodeGen/CGExpr.cpp
index 4101ca2..2d16766 100644
--- a/clang/lib/CodeGen/CGExpr.cpp
+++ b/clang/lib/CodeGen/CGExpr.cpp
@@ -27,6 +27,7 @@
 #include "clang/AST/NSAPI.h"
 #include "clang/Basic/Builtins.h"
 #include "clang/Basic/CodeGenOptions.h"
+#include "clang/Basic/SourceManager.h"
 #include "llvm/ADT/Hashing.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/IR/DataLayout.h"
diff --git a/clang/lib/CodeGen/CGOpenMPRuntime.cpp b/clang/lib/CodeGen/CGOpenMPRuntime.cpp
index f00dcfe..77a62b1 100644
--- a/clang/lib/CodeGen/CGOpenMPRuntime.cpp
+++ b/clang/lib/CodeGen/CGOpenMPRuntime.cpp
@@ -22,6 +22,7 @@
 #include "clang/AST/StmtVisitor.h"
 #include "clang/Basic/BitmaskEnum.h"
 #include "clang/Basic/OpenMPKinds.h"
+#include "clang/Basic/SourceManager.h"
 #include "clang/CodeGen/ConstantInitBuilder.h"
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/SetOperations.h"
diff --git a/clang/lib/CodeGen/CGStmt.cpp b/clang/lib/CodeGen/CGStmt.cpp
index a49601f..238e049 100644
--- a/clang/lib/CodeGen/CGStmt.cpp
+++ b/clang/lib/CodeGen/CGStmt.cpp
@@ -18,6 +18,7 @@
 #include "clang/AST/StmtVisitor.h"
 #include "clang/Basic/Builtins.h"
 #include "clang/Basic/PrettyStackTrace.h"
+#include "clang/Basic/SourceManager.h"
 #include "clang/Basic/TargetInfo.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/IR/DataLayout.h"
diff --git a/clang/lib/CodeGen/SanitizerMetadata.cpp b/clang/lib/CodeGen/SanitizerMetadata.cpp
index 24ae6c6..86269b5 100644
--- a/clang/lib/CodeGen/SanitizerMetadata.cpp
+++ b/clang/lib/CodeGen/SanitizerMetadata.cpp
@@ -13,6 +13,7 @@
 #include "CodeGenModule.h"
 #include "clang/AST/Attr.h"
 #include "clang/AST/Type.h"
+#include "clang/Basic/SourceManager.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/IR/Constants.h"
 
diff --git a/clang/lib/Index/CommentToXML.cpp b/clang/lib/Index/CommentToXML.cpp
index ce6f9e2..1281896 100644
--- a/clang/lib/Index/CommentToXML.cpp
+++ b/clang/lib/Index/CommentToXML.cpp
@@ -11,6 +11,7 @@
 #include "clang/AST/Attr.h"
 #include "clang/AST/Comment.h"
 #include "clang/AST/CommentVisitor.h"
+#include "clang/Basic/SourceManager.h"
 #include "clang/Format/Format.h"
 #include "clang/Index/USRGeneration.h"
 #include "llvm/ADT/StringExtras.h"
diff --git a/clang/lib/Index/FileIndexRecord.cpp b/clang/lib/Index/FileIndexRecord.cpp
index c9dcb0f..753bdf2 100644
--- a/clang/lib/Index/FileIndexRecord.cpp
+++ b/clang/lib/Index/FileIndexRecord.cpp
@@ -10,6 +10,7 @@
 #include "FileIndexRecord.h"
 #include "clang/AST/ASTContext.h"
 #include "clang/AST/DeclTemplate.h"
+#include "clang/Basic/SourceManager.h"
 #include "llvm/ADT/SmallString.h"
 #include "llvm/Support/Path.h"
 
diff --git a/clang/lib/Sema/DeclSpec.cpp b/clang/lib/Sema/DeclSpec.cpp
index eca9773..2da300a 100644
--- a/clang/lib/Sema/DeclSpec.cpp
+++ b/clang/lib/Sema/DeclSpec.cpp
@@ -17,6 +17,7 @@
 #include "clang/AST/LocInfoType.h"
 #include "clang/AST/TypeLoc.h"
 #include "clang/Basic/LangOptions.h"
+#include "clang/Basic/SourceManager.h"
 #include "clang/Basic/TargetInfo.h"
 #include "clang/Sema/ParsedTemplate.h"
 #include "clang/Sema/Sema.h"
diff --git a/clang/lib/Sema/Sema.cpp b/clang/lib/Sema/Sema.cpp
index e24db71..186c0c7 100644
--- a/clang/lib/Sema/Sema.cpp
+++ b/clang/lib/Sema/Sema.cpp
@@ -22,6 +22,7 @@
 #include "clang/AST/StmtCXX.h"
 #include "clang/Basic/DiagnosticOptions.h"
 #include "clang/Basic/PartialDiagnostic.h"
+#include "clang/Basic/SourceManager.h"
 #include "clang/Basic/Stack.h"
 #include "clang/Basic/TargetInfo.h"
 #include "clang/Lex/HeaderSearch.h"
diff --git a/clang/lib/Sema/SemaInit.cpp b/clang/lib/Sema/SemaInit.cpp
index 61bb1f0..0e7b839 100644
--- a/clang/lib/Sema/SemaInit.cpp
+++ b/clang/lib/Sema/SemaInit.cpp
@@ -17,6 +17,7 @@
 #include "clang/AST/ExprOpenMP.h"
 #include "clang/AST/TypeLoc.h"
 #include "clang/Basic/CharInfo.h"
+#include "clang/Basic/SourceManager.h"
 #include "clang/Basic/TargetInfo.h"
 #include "clang/Sema/Designator.h"
 #include "clang/Sema/Initialization.h"
diff --git a/clang/lib/Sema/SemaOverload.cpp b/clang/lib/Sema/SemaOverload.cpp
index a10b7cd..b4be10d 100644
--- a/clang/lib/Sema/SemaOverload.cpp
+++ b/clang/lib/Sema/SemaOverload.cpp
@@ -21,6 +21,7 @@
 #include "clang/Basic/Diagnostic.h"
 #include "clang/Basic/DiagnosticOptions.h"
 #include "clang/Basic/PartialDiagnostic.h"
+#include "clang/Basic/SourceManager.h"
 #include "clang/Basic/TargetInfo.h"
 #include "clang/Sema/Initialization.h"
 #include "clang/Sema/Lookup.h"
diff --git a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
index 2ac899a..08529e5 100755
--- a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
+++ b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
@@ -8,6 +8,7 @@
 //  This file implements C++ template instantiation for declarations.
 //
 //===----------------------------------------------------------------------===/
+
 #include "clang/Sema/SemaInternal.h"
 #include "clang/AST/ASTConsumer.h"
 #include "clang/AST/ASTContext.h"
@@ -19,6 +20,7 @@
 #include "clang/AST/ExprCXX.h"
 #include "clang/AST/PrettyDeclStackTrace.h"
 #include "clang/AST/TypeLoc.h"
+#include "clang/Basic/SourceManager.h"
 #include "clang/Sema/Initialization.h"
 #include "clang/Sema/Lookup.h"
 #include "clang/Sema/Template.h"
diff --git a/clang/lib/Tooling/ASTDiff/ASTDiff.cpp b/clang/lib/Tooling/ASTDiff/ASTDiff.cpp
index 6faaf5d..0821863 100644
--- a/clang/lib/Tooling/ASTDiff/ASTDiff.cpp
+++ b/clang/lib/Tooling/ASTDiff/ASTDiff.cpp
@@ -11,9 +11,9 @@
 //===----------------------------------------------------------------------===//
 
 #include "clang/Tooling/ASTDiff/ASTDiff.h"
-
 #include "clang/AST/ParentMapContext.h"
 #include "clang/AST/RecursiveASTVisitor.h"
+#include "clang/Basic/SourceManager.h"
 #include "clang/Lex/Lexer.h"
 #include "llvm/ADT/PriorityQueue.h"
 
diff --git a/clang/lib/Tooling/Core/Lookup.cpp b/clang/lib/Tooling/Core/Lookup.cpp
index 624a55c..aa83e56 100644
--- a/clang/lib/Tooling/Core/Lookup.cpp
+++ b/clang/lib/Tooling/Core/Lookup.cpp
@@ -15,6 +15,7 @@
 #include "clang/AST/DeclCXX.h"
 #include "clang/AST/DeclarationName.h"
 #include "clang/Basic/SourceLocation.h"
+#include "clang/Basic/SourceManager.h"
 #include "llvm/ADT/SmallVector.h"
 using namespace clang;
 using namespace clang::tooling;
diff --git a/clang/lib/Tooling/Refactoring/Rename/USRFinder.cpp b/clang/lib/Tooling/Refactoring/Rename/USRFinder.cpp
index 5511120..23f567f 100644
--- a/clang/lib/Tooling/Refactoring/Rename/USRFinder.cpp
+++ b/clang/lib/Tooling/Refactoring/Rename/USRFinder.cpp
@@ -15,6 +15,7 @@
 #include "clang/AST/AST.h"
 #include "clang/AST/ASTContext.h"
 #include "clang/AST/RecursiveASTVisitor.h"
+#include "clang/Basic/SourceManager.h"
 #include "clang/Index/USRGeneration.h"
 #include "clang/Lex/Lexer.h"
 #include "clang/Tooling/Refactoring/RecursiveSymbolVisitor.h"
diff --git a/clang/lib/Tooling/Transformer/SourceCode.cpp b/clang/lib/Tooling/Transformer/SourceCode.cpp
index 8d59487..38b331b 100644
--- a/clang/lib/Tooling/Transformer/SourceCode.cpp
+++ b/clang/lib/Tooling/Transformer/SourceCode.cpp
@@ -17,6 +17,7 @@
 #include "clang/AST/DeclCXX.h"
 #include "clang/AST/DeclTemplate.h"
 #include "clang/AST/Expr.h"
+#include "clang/Basic/SourceManager.h"
 #include "clang/Lex/Lexer.h"
 #include "llvm/Support/Errc.h"