From 97e10d64e8ef43258456e83295719f3103e78f1e Mon Sep 17 00:00:00 2001
From: Argyrios Kyrtzidis <akyrtzi@gmail.com>
Date: Sun, 5 Jul 2009 22:21:28 +0000
Subject: [PATCH] Introduce ASTNode class into the AST library.

ASTNode is an immutable pair of a Decl and Stmt. If Stmt is not null, Decl should be its immediate parent.

llvm-svn: 74797
---
 clang/include/clang/AST/ASTNode.h | 66 +++++++++++++++++++++++
 clang/lib/AST/ASTNode.cpp         | 90 +++++++++++++++++++++++++++++++
 clang/lib/AST/CMakeLists.txt      |  1 +
 3 files changed, 157 insertions(+)
 create mode 100644 clang/include/clang/AST/ASTNode.h
 create mode 100644 clang/lib/AST/ASTNode.cpp

diff --git a/clang/include/clang/AST/ASTNode.h b/clang/include/clang/AST/ASTNode.h
new file mode 100644
index 000000000000..852e94638057
--- /dev/null
+++ b/clang/include/clang/AST/ASTNode.h
@@ -0,0 +1,66 @@
+//===--- ASTNode.h - A <Decl, Stmt> pair ------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+//  ASTNode is Decl or a Stmt and its immediate Decl parent.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_AST_ASTNODE_H
+#define LLVM_CLANG_AST_ASTNODE_H
+
+#include <cassert>
+
+namespace llvm {
+  class raw_ostream;
+}
+
+namespace clang {
+  class Decl;
+  class Stmt;
+
+/// \brief Represents a Decl or a Stmt and its immediate Decl parent. It's
+/// immutable.
+class ASTNode {
+  Decl *D;
+  Stmt *Stm;
+
+public:
+  ASTNode() : D(0), Stm(0) {}
+
+  explicit ASTNode(const Decl *d, const Stmt *stm = 0)
+    : D(const_cast<Decl*>(d)), Stm(const_cast<Stmt*>(stm)) {
+    assert((Stm == 0 || isImmediateParent(D, Stm)) &&
+           "The Decl is not the immediate parent of the Stmt.");
+  }
+
+  const Decl *getDecl() const { return D; }
+  const Stmt *getStmt() const { return Stm; }
+  Decl *getDecl() { return D; }
+  Stmt *getStmt() { return Stm; }
+
+  bool isValid() const { return D != 0; }
+  bool isInvalid() const { return !isValid(); }
+  bool hasStmt() const { return Stm != 0; }
+
+  /// \brief Checks that D is the immediate Decl parent of Node.
+  static bool isImmediateParent(Decl *D, Stmt *Node);
+
+  friend bool operator==(const ASTNode &L, const ASTNode &R) { 
+    return L.D == R.D && L.Stm == R.Stm;
+  }
+  friend bool operator!=(const ASTNode &L, const ASTNode &R) { 
+    return !(L == R);
+  }
+  
+  void print(llvm::raw_ostream &OS);
+};
+
+} // namespace clang
+
+#endif
diff --git a/clang/lib/AST/ASTNode.cpp b/clang/lib/AST/ASTNode.cpp
new file mode 100644
index 000000000000..ff5ecc10de73
--- /dev/null
+++ b/clang/lib/AST/ASTNode.cpp
@@ -0,0 +1,90 @@
+//===--- ASTNode.h - A <Decl, Stmt> pair ------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+//  ASTNode is Decl or a Stmt and its immediate Decl parent.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/AST/ASTNode.h"
+#include "clang/AST/Decl.h"
+#include "clang/AST/Stmt.h"
+#include "clang/AST/Expr.h"
+using namespace clang;
+
+static bool isContainedInStatement(Stmt *Node, Stmt *Parent) {
+  assert(Node && Parent && "Passed null Node or Parent");
+  
+  if (Node == Parent)
+    return true;
+  
+  for (Stmt::child_iterator
+         I = Parent->child_begin(), E = Parent->child_end(); I != E; ++I) {
+    if (isContainedInStatement(Node, *I))
+      return true;
+  }
+  
+  return false;
+}
+
+static Decl *FindImmediateParent(Decl *D, Stmt *Node) {
+  assert(D && Node && "Passed null Decl or null Stmt");
+
+  if (VarDecl *VD = dyn_cast<VarDecl>(D)) {
+    Expr *Init = VD->getInit();
+    if (Init == 0)
+      return 0;
+    return isContainedInStatement(Node, Init) ? D : 0;
+  }
+  
+  if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
+    if (!FD->isThisDeclarationADefinition())
+      return 0;
+    
+    for (DeclContext::decl_iterator
+           I = FD->decls_begin(), E = FD->decls_end(); I != E; ++I) {
+      Decl *Child = FindImmediateParent(*I, Node);
+      if (Child)
+        return Child;
+    }
+    
+    assert(FD->getBody() && "If not definition we should have exited already");
+    return isContainedInStatement(Node, FD->getBody()) ? D : 0;
+  }
+  
+  return 0;
+}
+
+bool ASTNode::isImmediateParent(Decl *D, Stmt *Node) {
+  assert(D && Node && "Passed null Decl or null Stmt");
+  return D == FindImmediateParent(D, Node);
+}
+
+void ASTNode::print(llvm::raw_ostream &OS) {
+  assert(isValid() && "ASTNode is not valid");
+
+  OS << "[Decl: " << getDecl()->getDeclKindName() << " ";
+  if (NamedDecl *ND = dyn_cast<NamedDecl>(getDecl()))
+    OS << ND->getNameAsString();
+  
+  if (getStmt()) {
+    ASTContext &Ctx = getDecl()->getASTContext();
+    OS << " | Stmt: " << getStmt()->getStmtClassName() << " ";
+    getStmt()->printPretty(OS, Ctx, 0, PrintingPolicy(Ctx.getLangOptions()));
+  }
+
+  OS << "] <";
+  
+  SourceRange Range = hasStmt() ? getStmt()->getSourceRange()
+                                : getDecl()->getSourceRange();
+  SourceManager &SourceMgr = getDecl()->getASTContext().getSourceManager();
+  Range.getBegin().print(OS, SourceMgr);
+  OS << ", ";
+  Range.getEnd().print(OS, SourceMgr);
+  OS << ">\n";
+}
diff --git a/clang/lib/AST/CMakeLists.txt b/clang/lib/AST/CMakeLists.txt
index ac4cbb2d296e..8fb86c6fc20b 100644
--- a/clang/lib/AST/CMakeLists.txt
+++ b/clang/lib/AST/CMakeLists.txt
@@ -4,6 +4,7 @@ add_clang_library(clangAST
   APValue.cpp
   ASTConsumer.cpp
   ASTContext.cpp
+  ASTNode.cpp
   CFG.cpp
   DeclarationName.cpp
   DeclBase.cpp