Give a length field to stack bitmaps.

runtime/vm/object.h

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #ifndef VM_OBJECT_H_
 #define VM_OBJECT_H_
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "platform/utils.h"
@@ skipping 2324 matching lines @@
   friend class Class;
 };
 
 
 class Stackmap : public Object {
  public:
   static const intptr_t kNoMaximum = -1;
   static const intptr_t kNoMinimum = -1;
 
   bool IsObject(intptr_t index) const {
-    return InRange(index) && GetBit(index);
+    ASSERT(InRange(index));
+    return GetBit(index);
   }
 
   RawCode* Code() const { return raw_ptr()->code_; }
   void SetCode(const dart::Code& code) const;
 
   intptr_t Length() const { return raw_ptr()->length_; }
 
   uword PC() const { return raw_ptr()->pc_; }
   void SetPC(uword value) const { raw_ptr()->pc_ = value; }
 
   static const intptr_t kMaxLengthInBytes = kSmiMax;
 
   static intptr_t InstanceSize() {
     ASSERT(sizeof(RawStackmap) == OFFSET_OF(RawStackmap, data_));
     return 0;
   }
   static intptr_t InstanceSize(intptr_t length) {
     ASSERT(length >= 0);
     // The stackmap payload is in an array of bytes.
     intptr_t payload_size =
         Utils::RoundUp(length, kBitsPerByte) / kBitsPerByte;
     return RoundedAllocationSize(sizeof(RawStackmap) + payload_size);
   }
-  static RawStackmap* New(intptr_t pc_offset,
-                          intptr_t length,
-                          BitmapBuilder* bmap);
+  static RawStackmap* New(intptr_t pc_offset, BitmapBuilder* bmap);
 
  private:
   void SetLength(intptr_t length) const { raw_ptr()->length_ = length; }
 
   bool InRange(intptr_t index) const { return index < Length(); }
 
   bool GetBit(intptr_t bit_index) const;
   void SetBit(intptr_t bit_index, bool value) const;
 
   HEAP_OBJECT_IMPLEMENTATION(Stackmap, Object);
@@ skipping 3135 matching lines @@
     if (this->CharAt(i) != str.CharAt(begin_index + i)) {
       return false;
     }
   }
   return true;
 }
 
 }  // namespace dart
 
 #endif  // VM_OBJECT_H_