Initial support for count-based profiling

src/full-codegen.h

 // Copyright 2012 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 406 matching lines @@
 
   // Platform-specific code for a variable, constant, or function
   // declaration.  Functions have an initial value.
   // Increments global_count_ for unallocated variables.
   void EmitDeclaration(VariableProxy* proxy,
                        VariableMode mode,
                        FunctionLiteral* function);
 
   // Platform-specific code for checking the stack limit at the back edge of
   // a loop.
-  void EmitStackCheck(IterationStatement* stmt);
+  // This is meant to be called at loop back edges, |back_edge_target| is
+  // the jump target of the back edge and is used to approximate the amount
+  // of code inside the loop.
+  void EmitStackCheck(IterationStatement* stmt, Label* back_edge_target);
   // Record the OSR AST id corresponding to a stack check in the code.
   void RecordStackCheck(unsigned osr_ast_id);
   // Emit a table of stack check ids and pcs into the code stream.  Return
   // the offset of the start of the table.
   unsigned EmitStackCheckTable();
 
   // Platform-specific return sequence
   void EmitReturnSequence();
 
   // Platform-specific code sequences for calls
@@ skipping 329 matching lines @@
   Scope* scope_;
   Label return_label_;
   NestedStatement* nesting_stack_;
   int loop_depth_;
   int global_count_;
   const ExpressionContext* context_;
   ZoneList<BailoutEntry> bailout_entries_;
   ZoneList<BailoutEntry> stack_checks_;
   ZoneList<TypeFeedbackCellEntry> type_feedback_cells_;
   Handle<FixedArray> handler_table_;
+  Handle<JSGlobalPropertyCell> profiling_counter_;
 
   friend class NestedStatement;
 
   DISALLOW_COPY_AND_ASSIGN(FullCodeGenerator);
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_FULL_CODEGEN_H_