Start adding support for printing out parser callbacks and adding ast building

llvm-svn: 38933
diff --git a/clang/Driver/PrintParserCallbacks.cpp b/clang/Driver/PrintParserCallbacks.cpp
new file mode 100644
index 0000000..9f10fb5
--- /dev/null
+++ b/clang/Driver/PrintParserCallbacks.cpp
@@ -0,0 +1,57 @@
+//===--- PrintParserActions.cpp - Implement -parse-print-callbacks mode ---===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file was developed by Chris Lattner and is distributed under
+// the University of Illinois Open Source License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This code simply runs the preprocessor on the input file and prints out the
+// result.  This is the traditional behavior of the -E option.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang.h"
+#include "clang/Lex/IdentifierTable.h"
+#include "clang/Parse/Action.h"
+#include "clang/Parse/Declarations.h"
+#include <iostream>
+
+using namespace llvm;
+using namespace clang;
+
+namespace {
+  class ParserPrintActions : public EmptyAction {
+    
+    /// ParseDeclarator - This callback is invoked when a declarator is parsed and
+    /// 'Init' specifies the initializer if any.  This is for things like:
+    /// "int X = 4" or "typedef int foo".
+    virtual void ParseDeclarator(SourceLocation Loc, Scope *S, Declarator &D,
+                                 ExprTy *Init) {
+      std::cout << "ParseDeclarator ";
+      if (IdentifierInfo *II = D.getIdentifier()) {
+        std::cout << "'" << II->getName() << "'";
+      } else {
+        std::cout << "<anon>";
+      }
+      std::cout << "\n";
+      
+      // Pass up to EmptyActions so that the symbol table is maintained right.
+      EmptyAction::ParseDeclarator(Loc, S, D, Init);
+    }
+    
+    /// PopScope - This callback is called immediately before the specified scope
+    /// is popped and deleted.
+    virtual void PopScope(SourceLocation Loc, Scope *S) {
+      std::cout << "PopScope\n";
+      
+      // Pass up to EmptyActions so that the symbol table is maintained right.
+      EmptyAction::PopScope(Loc, S);
+    }
+  };
+}
+
+Action *llvm::clang::CreatePrintParserActionsAction() {
+  return new ParserPrintActions();
+}