More precise break points and stepping when debugging...

src/full-codegen.h

 // Copyright 2010 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 41 matching lines @@
 #define DECLARE_VISIT(type) virtual void Visit##type(type* node);
   AST_NODE_LIST(DECLARE_VISIT)
 #undef DECLARE_VISIT
 
   bool has_supported_syntax_;
 
   DISALLOW_COPY_AND_ASSIGN(FullCodeGenSyntaxChecker);
 };
 
 
+// AST node visitor which can tell whether a given statement will be breakable
+// when the code is compiled by the full compiler in the debugger. This means
+// that there will be an IC (load/store/call) in the code generated for the
+// debugger to piggybag on.
+class BreakableStatementChecker: public AstVisitor {
+ public:
+  BreakableStatementChecker() : is_breakable_(false) {}
+
+  void Check(Statement* stmt);
+  void Check(Expression* stmt);
+
+  bool is_breakable() { return is_breakable_; }
+
+ private:
+  // AST node visit functions.
+#define DECLARE_VISIT(type) virtual void Visit##type(type* node);
+  AST_NODE_LIST(DECLARE_VISIT)
+#undef DECLARE_VISIT
+
+  bool is_breakable_;
+
+  DISALLOW_COPY_AND_ASSIGN(BreakableStatementChecker);
+};
+
+
 // -----------------------------------------------------------------------------
 // Full code generator.
 
 class FullCodeGenerator: public AstVisitor {
  public:
   enum Mode {
     PRIMARY,
     SECONDARY
   };
 
@@ skipping 379 matching lines @@
   void EmitNullCompare(bool strict,
                        Register obj,
                        Register null_const,
                        Label* if_true,
                        Label* if_false,
                        Register scratch);
 
   void SetFunctionPosition(FunctionLiteral* fun);
   void SetReturnPosition(FunctionLiteral* fun);
   void SetStatementPosition(Statement* stmt);
+  void SetExpressionPosition(Expression* expr, int pos);
   void SetStatementPosition(int pos);
   void SetSourcePosition(int pos);
 
   // Non-local control flow support.
   void EnterFinallyBlock();
   void ExitFinallyBlock();
 
   // Loop nesting counter.
   int loop_depth() { return loop_depth_; }
   void increment_loop_depth() { loop_depth_++; }
@@ skipping 41 matching lines @@
 
   friend class NestedStatement;
 
   DISALLOW_COPY_AND_ASSIGN(FullCodeGenerator);
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_FULL_CODEGEN_H_