[interpreter, debugger] support debug breaks via bytecode array copy

src/heap/heap.cc

 // Copyright 2012 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.
 
 #include "src/heap/heap.h"
 
 #include "src/accessors.h"
 #include "src/api.h"
 #include "src/ast/scopeinfo.h"
 #include "src/base/bits.h"
@@ skipping 3340 matching lines @@
 
   // Relocate the copy.
   DCHECK(IsAligned(bit_cast<intptr_t>(new_code->address()), kCodeAlignment));
   DCHECK(isolate_->code_range() == NULL || !isolate_->code_range()->valid() ||
          isolate_->code_range()->contains(code->address()) ||
          obj_size <= code_space()->AreaSize());
   new_code->Relocate(new_addr - old_addr);
   return new_code;
 }
 
+AllocationResult Heap::CopyBytecodeArray(BytecodeArray* bytecode_array) {
+  int size = BytecodeArray::SizeFor(bytecode_array->length());
+  HeapObject* result = nullptr;
+  {
+    AllocationResult allocation = AllocateRaw(size, OLD_SPACE);
+    if (!allocation.To(&result)) return allocation;
+  }
+
+  result->set_map_no_write_barrier(bytecode_array_map());
+  BytecodeArray* copy = BytecodeArray::cast(result);
+  copy->set_length(bytecode_array->length());
+  copy->set_frame_size(bytecode_array->frame_size());
+  copy->set_parameter_count(bytecode_array->parameter_count());
+  copy->set_constant_pool(bytecode_array->constant_pool());
+  copy->set_handler_table(bytecode_array->handler_table());
+  copy->set_source_position_table(bytecode_array->source_position_table());
+  bytecode_array->CopyBytecodesTo(copy);
+  return copy;
+}
 
 AllocationResult Heap::CopyCode(Code* code, Vector<byte> reloc_info) {
   // Allocate ByteArray before the Code object, so that we do not risk
   // leaving uninitialized Code object (and breaking the heap).
   ByteArray* reloc_info_array = nullptr;
   {
     AllocationResult allocation =
         AllocateByteArray(reloc_info.length(), TENURED);
     if (!allocation.To(&reloc_info_array)) return allocation;
   }
@@ skipping 2931 matching lines @@
 }
 
 
 // static
 int Heap::GetStaticVisitorIdForMap(Map* map) {
   return StaticVisitorBase::GetVisitorId(map);
 }
 
 }  // namespace internal
 }  // namespace v8