Begin using a list of bailouts instead of a singleton in the fast code generator.

src/compiler.h

 // Copyright 2006-2008 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 23 matching lines @@
 #include "register-allocator.h"
 #include "zone.h"
 
 namespace v8 {
 namespace internal {
 
 // CompilationInfo encapsulates some information known at compile time.  It
 // is constructed based on the resources available at compile-time.
 class CompilationInfo BASE_EMBEDDED {
  public:
+  // Compilation mode.  Either the compiler is used as the primary
+  // compiler and needs to setup everything or the compiler is used as
+  // the secondary compiler for split compilation and has to handle
+  // bailouts.
+  enum Mode {
+    PRIMARY,
+    SECONDARY
+  };
+
+  // A description of the compilation state at a bailout to the secondary
+  // code generator.
+  //
+  // The state is currently simple: there are no parameters or local
+  // variables to worry about ('this' can be found in the stack frame).
+  // There are at most two live values.
+  //
+  // There is a label that should be bound to the beginning of the bailout
+  // stub code.
+  class Bailout : public ZoneObject {
+   public:
+    Bailout(Register left, Register right) : left_(left), right_(right) {}

[fschneider, 2010/02/19 14:47:14]

label_ needs to be initialized here.

+
+    Label* label() { return &label_; }
+
+   private:
+    Register left_;
+    Register right_;
+    Label label_;
+  };
+
+
   // Lazy compilation of a JSFunction.
   CompilationInfo(Handle<JSFunction> closure,
                   int loop_nesting,
                   Handle<Object> receiver)
       : closure_(closure),
         function_(NULL),
         is_eval_(false),
         loop_nesting_(loop_nesting),
         receiver_(receiver) {
     Initialize();
@@ skipping 56 matching lines @@
   void set_function(FunctionLiteral* literal) {
     ASSERT(function_ == NULL);
     function_ = literal;
   }
 
   // Simple accessors.
   bool is_eval() { return is_eval_; }
   int loop_nesting() { return loop_nesting_; }
   bool has_receiver() { return !receiver_.is_null(); }
   Handle<Object> receiver() { return receiver_; }
+  List<Bailout*>* bailouts() { return &bailouts_; }
 
-  // Accessors for mutable fields, possibly set by analysis passes with
+  // Accessors for mutable fields (possibly set by analysis passes) with
   // default values given by Initialize.
+  Mode mode() { return mode_; }
+  void set_mode(Mode mode) { mode_ = mode; }
+
   bool has_this_properties() { return has_this_properties_; }
   void set_has_this_properties(bool flag) { has_this_properties_ = flag; }
 
   bool has_global_object() {
     return !closure().is_null() && (closure()->context()->global() != NULL);
   }
 
   GlobalObject* global_object() {
     return has_global_object() ? closure()->context()->global() : NULL;
   }
 
   bool has_globals() { return has_globals_; }
   void set_has_globals(bool flag) { has_globals_ = flag; }
 
   // Derived accessors.
   Scope* scope() { return function()->scope(); }
 
+  // Add a bailout with two live values.
+  Label* AddBailout(Register left, Register right) {
+    Bailout* bailout = new Bailout(left, right);
+    bailouts_.Add(bailout);
+    return bailout->label();
+  }
+
+  // Add a bailout with no live values.
+  Label* AddBailout() { return AddBailout(no_reg, no_reg); }
+
  private:
   void Initialize() {
+    mode_ = PRIMARY;
     has_this_properties_ = false;
     has_globals_ = false;
   }
 
   Handle<JSFunction> closure_;
   Handle<SharedFunctionInfo> shared_info_;
   Handle<Script> script_;
 
   FunctionLiteral* function_;
+  Mode mode_;
 
   bool is_eval_;
   int loop_nesting_;
 
   Handle<Object> receiver_;
 
   bool has_this_properties_;
   bool has_globals_;
 
+  // An ordered list of bailout points encountered during fast-path
+  // compilation.
+  List<Bailout*> bailouts_;
+
   DISALLOW_COPY_AND_ASSIGN(CompilationInfo);
 };
 
 
 // The V8 compiler
 //
 // General strategy: Source code is translated into an anonymous function w/o
 // parameters which then can be executed. If the source code contains other
 // functions, they will be compiled and allocated as part of the compilation
 // of the source code.
@@ skipping 66 matching lines @@
       FrameElement::ClearConstantList();
       Result::ClearConstantList();
     }
   }
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_COMPILER_H_