Fix missing x87 tracking for deferred code.

When compiling deferred code we have to remember the corresponding stack state and ensure that the deferred code does not manipulate the order of elements.

BUG=
R=mstarzinger@chromium.org

Review URL: https://codereview.chromium.org/23135018

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16433 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/ia32/lithium-codegen-ia32.h

@@ -448,10 +448,10 @@ class LCodeGen V8_FINAL BASE_EMBEDDED {
 
   class X87Stack {
    public:
-    explicit X87Stack(MacroAssembler* masm) : stack_depth_(0), masm_(masm) { }
+    explicit X87Stack(MacroAssembler* masm)
+        : stack_depth_(0), is_mutable_(true), masm_(masm) { }
     explicit X87Stack(const X87Stack& other)
-        : stack_depth_(0), masm_(other.masm_) {
-      stack_depth_ = other.stack_depth_;
+        : stack_depth_(other.stack_depth_), is_mutable_(false), masm_(masm()) {
       for (int i = 0; i < stack_depth_; i++) {
         stack_[i] = other.stack_[i];
       }
@@ -470,8 +470,12 @@ class LCodeGen V8_FINAL BASE_EMBEDDED {
     void CommitWrite(X87Register reg);
     void FlushIfNecessary(LInstruction* instr, LCodeGen* cgen);
     int depth() const { return stack_depth_; }
-    void pop() { stack_depth_--; }
+    void pop() {
+      ASSERT(is_mutable_);
+      stack_depth_--;
+    }
     void push(X87Register reg) {
+      ASSERT(is_mutable_);
       ASSERT(stack_depth_ < X87Register::kNumAllocatableRegisters);
       stack_[stack_depth_] = reg;
       stack_depth_++;
@@ -482,9 +486,11 @@ class LCodeGen V8_FINAL BASE_EMBEDDED {
    private:
     int ArrayIndex(X87Register reg);
     int st2idx(int pos);
+
     X87Register stack_[X87Register::kNumAllocatableRegisters];
     int stack_depth_;
-    MacroAssembler* const masm_;
+    bool is_mutable_;
+    MacroAssembler* masm_;
   };
   X87Stack x87_stack_;
 
@@ -528,10 +534,11 @@ class LCodeGen V8_FINAL BASE_EMBEDDED {
 
 class LDeferredCode : public ZoneObject {
  public:
-  explicit LDeferredCode(LCodeGen* codegen)
+  explicit LDeferredCode(LCodeGen* codegen, const LCodeGen::X87Stack& x87_stack)
       : codegen_(codegen),
         external_exit_(NULL),
-        instruction_index_(codegen->current_instruction_) {
+        instruction_index_(codegen->current_instruction_),
+        x87_stack_(x87_stack) {
     codegen->AddDeferredCode(this);
   }
 
@@ -543,6 +550,7 @@ class LDeferredCode : public ZoneObject {
   Label* entry() { return &entry_; }
   Label* exit() { return external_exit_ != NULL ? external_exit_ : &exit_; }
   int instruction_index() const { return instruction_index_; }
+  const LCodeGen::X87Stack& x87_stack() const { return x87_stack_; }
 
  protected:
   LCodeGen* codegen() const { return codegen_; }
@@ -554,6 +562,7 @@ class LDeferredCode : public ZoneObject {
   Label exit_;
   Label* external_exit_;
   int instruction_index_;
+  LCodeGen::X87Stack x87_stack_;
 };
 
 } }  // namespace v8::internal