[Syntax] Build nodes for simple cases of top level declarations

Summary:
More complicated nodes (e.g. template declarations) will be implemented
in the follow-up patches.

Reviewers: gribozavr2

Reviewed By: gribozavr2

Subscribers: merge_guards_bot, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D70856

2 files changed, 104 insertions, 1 deletions

diff --git a/clang/lib/Tooling/Syntax/BuildTree.cpp b/clang/lib/Tooling/Syntax/BuildTree.cpp
index 67081497d04..e13bb2d0699 100644
--- a/clang/lib/Tooling/Syntax/BuildTree.cpp
+++ b/clang/lib/Tooling/Syntax/BuildTree.cpp
@@ -295,7 +295,7 @@ private:
 
   syntax::Arena &Arena;
   Forest Pending;
-  llvm::DenseSet<Decl*> DeclsWithoutSemicolons;
+  llvm::DenseSet<Decl *> DeclsWithoutSemicolons;
 };
 
 namespace {
@@ -397,6 +397,18 @@ public:
     return true;
   }
 
+  bool WalkUpFromNamespaceDecl(NamespaceDecl *S) {
+    auto Tokens = Builder.getRange(S);
+    if (Tokens.front().kind() == tok::coloncolon) {
+      // Handle nested namespace definitions. Those start at '::' token, e.g.
+      // namespace a^::b {}
+      // FIXME: build corresponding nodes for the name of this namespace.
+      return true;
+    }
+    Builder.foldNode(Tokens, new (allocator()) syntax::NamespaceDefinition);
+    return true;
+  }
+
   // The code below is very regular, it could even be generated with some
   // preprocessor magic. We merely assign roles to the corresponding children
   // and fold resulting nodes.
@@ -504,6 +516,64 @@ public:
     return true;
   }
 
+  bool WalkUpFromEmptyDecl(EmptyDecl *S) {
+    Builder.foldNode(Builder.getRange(S),
+                     new (allocator()) syntax::EmptyDeclaration);
+    return true;
+  }
+
+  bool WalkUpFromStaticAssertDecl(StaticAssertDecl *S) {
+    Builder.markExprChild(S->getAssertExpr(),
+                          syntax::NodeRole::StaticAssertDeclaration_condition);
+    Builder.markExprChild(S->getMessage(),
+                          syntax::NodeRole::StaticAssertDeclaration_message);
+    Builder.foldNode(Builder.getRange(S),
+                     new (allocator()) syntax::StaticAssertDeclaration);
+    return true;
+  }
+
+  bool WalkUpFromLinkageSpecDecl(LinkageSpecDecl *S) {
+    Builder.foldNode(Builder.getRange(S),
+                     new (allocator()) syntax::LinkageSpecificationDeclaration);
+    return true;
+  }
+
+  bool WalkUpFromNamespaceAliasDecl(NamespaceAliasDecl *S) {
+    Builder.foldNode(Builder.getRange(S),
+                     new (allocator()) syntax::NamespaceAliasDefinition);
+    return true;
+  }
+
+  bool WalkUpFromUsingDirectiveDecl(UsingDirectiveDecl *S) {
+    Builder.foldNode(Builder.getRange(S),
+                     new (allocator()) syntax::UsingNamespaceDirective);
+    return true;
+  }
+
+  bool WalkUpFromUsingDecl(UsingDecl *S) {
+    Builder.foldNode(Builder.getRange(S),
+                     new (allocator()) syntax::UsingDeclaration);
+    return true;
+  }
+
+  bool WalkUpFromUnresolvedUsingValueDecl(UnresolvedUsingValueDecl *S) {
+    Builder.foldNode(Builder.getRange(S),
+                     new (allocator()) syntax::UsingDeclaration);
+    return true;
+  }
+
+  bool WalkUpFromUnresolvedUsingTypenameDecl(UnresolvedUsingTypenameDecl *S) {
+    Builder.foldNode(Builder.getRange(S),
+                     new (allocator()) syntax::UsingDeclaration);
+    return true;
+  }
+
+  bool WalkUpFromTypeAliasDecl(TypeAliasDecl *S) {
+    Builder.foldNode(Builder.getRange(S),
+                     new (allocator()) syntax::TypeAliasDeclaration);
+    return true;
+  }
+
 private:
   /// A small helper to save some typing.
   llvm::BumpPtrAllocator &allocator() { return Builder.allocator(); }
@@ -553,6 +623,9 @@ void syntax::TreeBuilder::markStmtChild(Stmt *Child, NodeRole Role) {
 }
 
 void syntax::TreeBuilder::markExprChild(Expr *Child, NodeRole Role) {
+  if (!Child)
+    return;
+
   Pending.assignRole(getExprRange(Child), Role);
 }
 
diff --git a/clang/lib/Tooling/Syntax/Nodes.cpp b/clang/lib/Tooling/Syntax/Nodes.cpp
index b2ed4ffa22c..5b0c5107c13 100644
--- a/clang/lib/Tooling/Syntax/Nodes.cpp
+++ b/clang/lib/Tooling/Syntax/Nodes.cpp
@@ -50,8 +50,24 @@ llvm::raw_ostream &syntax::operator<<(llvm::raw_ostream &OS, NodeKind K) {
     return OS << "CompoundStatement";
   case NodeKind::UnknownDeclaration:
     return OS << "UnknownDeclaration";
+  case NodeKind::EmptyDeclaration:
+    return OS << "EmptyDeclaration";
+  case NodeKind::StaticAssertDeclaration:
+    return OS << "StaticAssertDeclaration";
+  case NodeKind::LinkageSpecificationDeclaration:
+    return OS << "LinkageSpecificationDeclaration";
   case NodeKind::SimpleDeclaration:
     return OS << "SimpleDeclaration";
+  case NodeKind::NamespaceDefinition:
+    return OS << "NamespaceDefinition";
+  case NodeKind::NamespaceAliasDefinition:
+    return OS << "NamespaceAliasDefinition";
+  case NodeKind::UsingNamespaceDirective:
+    return OS << "UsingNamespaceDirective";
+  case NodeKind::UsingDeclaration:
+    return OS << "UsingDeclaration";
+  case NodeKind::TypeAliasDeclaration:
+    return OS << "TypeAliasDeclaration";
   }
   llvm_unreachable("unknown node kind");
 }
@@ -84,6 +100,10 @@ llvm::raw_ostream &syntax::operator<<(llvm::raw_ostream &OS, NodeRole R) {
     return OS << "ExpressionStatement_expression";
   case syntax::NodeRole::CompoundStatement_statement:
     return OS << "CompoundStatement_statement";
+  case syntax::NodeRole::StaticAssertDeclaration_condition:
+    return OS << "StaticAssertDeclaration_condition";
+  case syntax::NodeRole::StaticAssertDeclaration_message:
+    return OS << "StaticAssertDeclaration_message";
   }
   llvm_unreachable("invalid role");
 }
@@ -216,3 +236,13 @@ syntax::Leaf *syntax::CompoundStatement::rbrace() {
   return llvm::cast_or_null<syntax::Leaf>(
       findChild(syntax::NodeRole::CloseParen));
 }
+
+syntax::Expression *syntax::StaticAssertDeclaration::condition() {
+  return llvm::cast_or_null<syntax::Expression>(
+      findChild(syntax::NodeRole::StaticAssertDeclaration_condition));
+}
+
+syntax::Expression *syntax::StaticAssertDeclaration::message() {
+  return llvm::cast_or_null<syntax::Expression>(
+      findChild(syntax::NodeRole::StaticAssertDeclaration_message));
+}