Add tracing of the stack height to full code generator.

src/full-codegen.h

 // Copyright 2011 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 65 matching lines @@
     NO_REGISTERS,
     TOS_REG
   };
 
   explicit FullCodeGenerator(MacroAssembler* masm)
       : masm_(masm),
         info_(NULL),
         scope_(NULL),
         nesting_stack_(NULL),
         loop_depth_(0),
+        stack_height_(0),
         context_(NULL),
         bailout_entries_(0),
         stack_checks_(2),  // There's always at least one.
         forward_bailout_stack_(NULL),
         forward_bailout_pending_(NULL) {
   }
 
   static bool MakeCode(CompilationInfo* info);
 
   void Generate(CompilationInfo* info);
@@ skipping 416 matching lines @@
   void ExitFinallyBlock();
 
   // Loop nesting counter.
   int loop_depth() { return loop_depth_; }
   void increment_loop_depth() { loop_depth_++; }
   void decrement_loop_depth() {
     ASSERT(loop_depth_ > 0);
     loop_depth_--;
   }
 
+#if defined(V8_TARGET_ARCH_IA32)
+  int stack_height() { return stack_height_; }
+  void set_stack_height(int depth) { stack_height_ = depth; }
+  void increment_stack_height() { stack_height_++; }
+  void increment_stack_height(int delta) { stack_height_ += delta; }
+  void decrement_stack_height() {
+    if (FLAG_verify_stack_height) {
+      ASSERT(stack_height_ > 0);
+    }
+    stack_height_--;
+  }
+  void decrement_stack_height(int delta) {
+    stack_height_-= delta;
+    if (FLAG_verify_stack_height) {
+      ASSERT(stack_height_ >= 0);
+    }
+  }
+  // Call this function only if FLAG_verify_stack_height is true.
+  void verify_stack_height();  // Generates a runtime check of esp - ebp.
+#else
+  int stack_height() { return 0; }
+  void set_stack_height(int depth) {}
+  void increment_stack_height() {}
+  void increment_stack_height(int delta) {}
+  void decrement_stack_height() {}
+  void decrement_stack_height(int delta) {}
+  void verify_stack_height() {}
+#endif  // V8_TARGET_ARCH_IA32
+
   MacroAssembler* masm() { return masm_; }
 
   class ExpressionContext;
   const ExpressionContext* context() { return context_; }
   void set_new_context(const ExpressionContext* context) { context_ = context; }
 
   Handle<Script> script() { return info_->script(); }
   bool is_eval() { return info_->is_eval(); }
   bool is_strict_mode() { return function()->strict_mode(); }
   StrictModeFlag strict_mode_flag() {
@@ skipping 39 matching lines @@
 
   class ExpressionContext BASE_EMBEDDED {
    public:
     explicit ExpressionContext(FullCodeGenerator* codegen)
         : masm_(codegen->masm()), old_(codegen->context()), codegen_(codegen) {
       codegen->set_new_context(this);
     }
 
     virtual ~ExpressionContext() {
       codegen_->set_new_context(old_);
+      if (FLAG_verify_stack_height) {
+        ASSERT_EQ(expected_stack_height_, codegen()->stack_height());
+        codegen()->verify_stack_height();
+      }
     }
 
     Isolate* isolate() const { return codegen_->isolate(); }
 
     // Convert constant control flow (true or false) to the result expected for
     // this expression context.
     virtual void Plug(bool flag) const = 0;
 
     // Emit code to convert a pure value (in a register, slot, as a literal,
     // or on top of the stack) into the result expected according to this
@@ skipping 33 matching lines @@
     virtual bool IsStackValue() const { return false; }
 
     // Returns true if we are branching on the value rather than materializing
     // it.  Only used for asserts.
     virtual bool IsTest() const { return false; }
 
    protected:
     FullCodeGenerator* codegen() const { return codegen_; }
     MacroAssembler* masm() const { return masm_; }
     MacroAssembler* masm_;
+    int expected_stack_height_;  // The expected stack height esp - ebp on exit.
 
    private:
     const ExpressionContext* old_;
     FullCodeGenerator* codegen_;
   };
 
   class AccumulatorValueContext : public ExpressionContext {
    public:
     explicit AccumulatorValueContext(FullCodeGenerator* codegen)
-        : ExpressionContext(codegen) { }
+        : ExpressionContext(codegen) {
+      expected_stack_height_ = codegen->stack_height();
+    }
 
     virtual void Plug(bool flag) const;
     virtual void Plug(Register reg) const;
     virtual void Plug(Label* materialize_true, Label* materialize_false) const;
     virtual void Plug(Slot* slot) const;
     virtual void Plug(Handle<Object> lit) const;
     virtual void Plug(Heap::RootListIndex) const;
     virtual void PlugTOS() const;
     virtual void DropAndPlug(int count, Register reg) const;
     virtual void PrepareTest(Label* materialize_true,
                              Label* materialize_false,
                              Label** if_true,
                              Label** if_false,
                              Label** fall_through) const;
     virtual bool IsAccumulatorValue() const { return true; }
   };
 
   class StackValueContext : public ExpressionContext {
    public:
     explicit StackValueContext(FullCodeGenerator* codegen)
-        : ExpressionContext(codegen) { }
+        : ExpressionContext(codegen) {
+      expected_stack_height_ = codegen->stack_height() + 1;
+    }
 
     virtual void Plug(bool flag) const;
     virtual void Plug(Register reg) const;
     virtual void Plug(Label* materialize_true, Label* materialize_false) const;
     virtual void Plug(Slot* slot) const;
     virtual void Plug(Handle<Object> lit) const;
     virtual void Plug(Heap::RootListIndex) const;
     virtual void PlugTOS() const;
     virtual void DropAndPlug(int count, Register reg) const;
     virtual void PrepareTest(Label* materialize_true,
                              Label* materialize_false,
                              Label** if_true,
                              Label** if_false,
                              Label** fall_through) const;
     virtual bool IsStackValue() const { return true; }
   };
 
   class TestContext : public ExpressionContext {
    public:
     TestContext(FullCodeGenerator* codegen,
                 Expression* condition,
                 Label* true_label,
                 Label* false_label,
                 Label* fall_through)
         : ExpressionContext(codegen),
           condition_(condition),
           true_label_(true_label),
           false_label_(false_label),
-          fall_through_(fall_through) { }
+          fall_through_(fall_through) {
+      expected_stack_height_ = codegen->stack_height();
+    }
 
     static const TestContext* cast(const ExpressionContext* context) {
       ASSERT(context->IsTest());
       return reinterpret_cast<const TestContext*>(context);
     }
 
     Expression* condition() const { return condition_; }
     Label* true_label() const { return true_label_; }
     Label* false_label() const { return false_label_; }
     Label* fall_through() const { return fall_through_; }
@@ skipping 16 matching lines @@
    private:
     Expression* condition_;
     Label* true_label_;
     Label* false_label_;
     Label* fall_through_;
   };
 
   class EffectContext : public ExpressionContext {
    public:
     explicit EffectContext(FullCodeGenerator* codegen)
-        : ExpressionContext(codegen) { }
+        : ExpressionContext(codegen) {
+      expected_stack_height_ = codegen->stack_height();
+    }
+
 
     virtual void Plug(bool flag) const;
     virtual void Plug(Register reg) const;
     virtual void Plug(Label* materialize_true, Label* materialize_false) const;
     virtual void Plug(Slot* slot) const;
     virtual void Plug(Handle<Object> lit) const;
     virtual void Plug(Heap::RootListIndex) const;
     virtual void PlugTOS() const;
     virtual void DropAndPlug(int count, Register reg) const;
     virtual void PrepareTest(Label* materialize_true,
                              Label* materialize_false,
                              Label** if_true,
                              Label** if_false,
                              Label** fall_through) const;
     virtual bool IsEffect() const { return true; }
   };
 
   MacroAssembler* masm_;
   CompilationInfo* info_;
   Scope* scope_;
   Label return_label_;
   NestedStatement* nesting_stack_;
   int loop_depth_;
+  int stack_height_;
   const ExpressionContext* context_;
   ZoneList<BailoutEntry> bailout_entries_;
   ZoneList<BailoutEntry> stack_checks_;
   ForwardBailoutStack* forward_bailout_stack_;
   ForwardBailoutStack* forward_bailout_pending_;
 
   friend class NestedStatement;
 
   DISALLOW_COPY_AND_ASSIGN(FullCodeGenerator);
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_FULL_CODEGEN_H_