BuildTree.cpp | Explore in Territory

//===- BuildTree.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 "clang/Tooling/Syntax/BuildTree.h"
#include "clang/AST/ASTFwd.h"
#include "clang/AST/Decl.h"
#include "clang/AST/DeclBase.h"
#include "clang/AST/DeclCXX.h"
#include "clang/AST/DeclarationName.h"
#include "clang/AST/Expr.h"
#include "clang/AST/ExprCXX.h"
#include "clang/AST/IgnoreExpr.h"
#include "clang/AST/OperationKinds.h"
#include "clang/AST/RecursiveASTVisitor.h"
#include "clang/AST/Stmt.h"
#include "clang/AST/TypeLoc.h"
#include "clang/AST/TypeLocVisitor.h"
#include "clang/Basic/LLVM.h"
#include "clang/Basic/SourceLocation.h"
#include "clang/Basic/SourceManager.h"
#include "clang/Basic/Specifiers.h"
#include "clang/Basic/TokenKinds.h"
#include "clang/Lex/Lexer.h"
#include "clang/Lex/LiteralSupport.h"
#include "clang/Tooling/Syntax/Nodes.h"
#include "clang/Tooling/Syntax/TokenBufferTokenManager.h"
#include "clang/Tooling/Syntax/Tokens.h"
#include "clang/Tooling/Syntax/Tree.h"
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/PointerUnion.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/ScopeExit.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/Support/Allocator.h"
#include "llvm/Support/Casting.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/FormatVariadic.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/raw_ostream.h"
#include <cstddef>
#include <map>

usingnamespaceclang;

// Ignores the implicit `CXXConstructExpr` for copy/move constructor calls
// generated by the compiler, as well as in implicit conversions like the one
// wrapping `1` in `X x = 1;`.
static Expr *IgnoreImplicitConstructorSingleStep(Expr *E) { … }

// In:
// struct X {
//   X(int)
// };
// X x = X(1);
// Ignores the implicit `CXXFunctionalCastExpr` that wraps
// `CXXConstructExpr X(1)`.
static Expr *IgnoreCXXFunctionalCastExprWrappingConstructor(Expr *E) { … }

static Expr *IgnoreImplicit(Expr *E) { … }

LLVM_ATTRIBUTE_UNUSED
static bool isImplicitExpr(Expr *E) { … }

namespace {
/// Get start location of the Declarator from the TypeLoc.
/// E.g.:
///   loc of `(` in `int (a)`
///   loc of `*` in `int *(a)`
///   loc of the first `(` in `int (*a)(int)`
///   loc of the `*` in `int *(a)(int)`
///   loc of the first `*` in `const int *const *volatile a;`
///
/// It is non-trivial to get the start location because TypeLocs are stored
/// inside out. In the example above `*volatile` is the TypeLoc returned
/// by `Decl.getTypeSourceInfo()`, and `*const` is what `.getPointeeLoc()`
/// returns.
struct GetStartLoc : TypeLocVisitor<GetStartLoc, SourceLocation> { … };
} // namespace

static CallExpr::arg_range dropDefaultArgs(CallExpr::arg_range Args) { … }

static syntax::NodeKind getOperatorNodeKind(const CXXOperatorCallExpr &E) { … }

/// Get the start of the qualified name. In the examples below it gives the
/// location of the `^`:
///     `int ^a;`
///     `int *^a;`
///     `int ^a::S::f(){}`
static SourceLocation getQualifiedNameStart(NamedDecl *D) { … }

/// Gets the range of the initializer inside an init-declarator C++ [dcl.decl].
///     `int a;` -> range of ``,
///     `int *a = nullptr` -> range of `= nullptr`.
///     `int a{}` -> range of `{}`.
///     `int a()` -> range of `()`.
static SourceRange getInitializerRange(Decl *D) { … }

/// Gets the range of declarator as defined by the C++ grammar. E.g.
///     `int a;` -> range of `a`,
///     `int *a;` -> range of `*a`,
///     `int a[10];` -> range of `a[10]`,
///     `int a[1][2][3];` -> range of `a[1][2][3]`,
///     `int *a = nullptr` -> range of `*a = nullptr`.
///     `int S::f(){}` -> range of `S::f()`.
/// FIXME: \p Name must be a source range.
static SourceRange getDeclaratorRange(const SourceManager &SM, TypeLoc T,
                                      SourceLocation Name,
                                      SourceRange Initializer) { … }

namespace {
/// All AST hierarchy roots that can be represented as pointers.
ASTPtr;
/// Maintains a mapping from AST to syntax tree nodes. This class will get more
/// complicated as we support more kinds of AST nodes, e.g. TypeLocs.
/// FIXME: expose this as public API.
class ASTToSyntaxMapping { … };
} // namespace

/// A helper class for constructing the syntax tree while traversing a clang
/// AST.
///
/// At each point of the traversal we maintain a list of pending nodes.
/// Initially all tokens are added as pending nodes. When processing a clang AST
/// node, the clients need to:
///   - create a corresponding syntax node,
///   - assign roles to all pending child nodes with 'markChild' and
///     'markChildToken',
///   - replace the child nodes with the new syntax node in the pending list
///     with 'foldNode'.
///
/// Note that all children are expected to be processed when building a node.
///
/// Call finalize() to finish building the tree and consume the root node.
class syntax::TreeBuilder { … };

namespace {
class BuildTreeVisitor : public RecursiveASTVisitor<BuildTreeVisitor> { … };
} // namespace

void syntax::TreeBuilder::noticeDeclWithoutSemicolon(Decl *D) { … }

void syntax::TreeBuilder::markChildToken(SourceLocation Loc, NodeRole Role) { … }

void syntax::TreeBuilder::markChildToken(const syntax::Token *T, NodeRole R) { … }

void syntax::TreeBuilder::markChild(syntax::Node *N, NodeRole R) { … }

void syntax::TreeBuilder::markChild(ASTPtr N, NodeRole R) { … }
void syntax::TreeBuilder::markChild(NestedNameSpecifierLoc NNSLoc, NodeRole R) { … }

void syntax::TreeBuilder::markStmtChild(Stmt *Child, NodeRole Role) { … }

void syntax::TreeBuilder::markExprChild(Expr *Child, NodeRole Role) { … }

const syntax::Token *syntax::TreeBuilder::findToken(SourceLocation L) const { … }

syntax::TranslationUnit *syntax::buildSyntaxTree(Arena &A,
                                                 TokenBufferTokenManager& TBTM,
                                                 ASTContext &Context) { … }
llvm/clang/lib/Tooling/Syntax/BuildTree.cpp
