[turbofan] Fix OSR into functions where the expression stack is not empty.

src/compiler/frame.h

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_COMPILER_FRAME_H_
 #define V8_COMPILER_FRAME_H_
 
 #include "src/v8.h"
 
 #include "src/bit-vector.h"
 
 namespace v8 {
 namespace internal {
 namespace compiler {
 
 // Collects the spill slot requirements and the allocated general and double
 // registers for a compiled function. Frames are usually populated by the
 // register allocator and are used by Linkage to generate code for the prologue
 // and epilogue to compiled code.
 class Frame : public ZoneObject {
  public:
   Frame()
       : register_save_area_size_(0),
         spill_slot_count_(0),
         double_spill_slot_count_(0),
+        osr_stack_slots_(0),
         allocated_registers_(NULL),
         allocated_double_registers_(NULL) {}
 
   inline int GetSpillSlotCount() { return spill_slot_count_; }
   inline int GetDoubleSpillSlotCount() { return double_spill_slot_count_; }
 
   void SetAllocatedRegisters(BitVector* regs) {
     DCHECK(allocated_registers_ == NULL);
     allocated_registers_ = regs;
   }
 
   void SetAllocatedDoubleRegisters(BitVector* regs) {
     DCHECK(allocated_double_registers_ == NULL);
     allocated_double_registers_ = regs;
   }
 
   bool DidAllocateDoubleRegisters() {
     return !allocated_double_registers_->IsEmpty();
   }
 
   void SetRegisterSaveAreaSize(int size) {
     DCHECK(IsAligned(size, kPointerSize));
     register_save_area_size_ = size;
   }
 
   int GetRegisterSaveAreaSize() { return register_save_area_size_; }
 
+  // OSR stack slots, including locals and expression stack slots.
+  void SetOsrStackSlots(int slots) {
+    DCHECK(slots >= 0);
+    osr_stack_slots_ = slots;
+  }
+
+  int GetOsrStackSlots() { return osr_stack_slots_; }
+
   int AllocateSpillSlot(bool is_double) {
     // If 32-bit, skip one if the new slot is a double.
     if (is_double) {
       if (kDoubleSize > kPointerSize) {
         DCHECK(kDoubleSize == kPointerSize * 2);
         spill_slot_count_++;
         spill_slot_count_ |= 1;
       }
       double_spill_slot_count_++;
     }
     return spill_slot_count_++;
   }
 
   void ReserveSpillSlots(size_t slot_count) {
     DCHECK_EQ(0, spill_slot_count_);  // can only reserve before allocation.
     spill_slot_count_ = static_cast<int>(slot_count);
   }
 
  private:
   int register_save_area_size_;
   int spill_slot_count_;
   int double_spill_slot_count_;
+  int osr_stack_slots_;

[Michael Starzinger, 2015/01/30 14:46:17]

nit: s/osr_stack_slots_/osr_stack_slot_count_/

   BitVector* allocated_registers_;
   BitVector* allocated_double_registers_;
 
   DISALLOW_COPY_AND_ASSIGN(Frame);
 };
 
 
 // Represents an offset from either the stack pointer or frame pointer.
 class FrameOffset {
  public:
@@ skipping 17 matching lines @@
   int offset_;  // Encodes SP or FP in the low order bit.
 
   static const int kFromSp = 1;
   static const int kFromFp = 0;
 };
 }
 }
 }  // namespace v8::internal::compiler
 
 #endif  // V8_COMPILER_FRAME_H_