Use map to distinguish type feedback vectors.

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/context-slot-cache.h"
 #include "src/base/bits.h"
@@ skipping 2229 matching lines @@
     field_name##_map()->SetConstructorFunctionIndex(            \
         (constructor_function_index));                          \
   }
 
     ALLOCATE_VARSIZE_MAP(FIXED_ARRAY_TYPE, fixed_cow_array)
     fixed_cow_array_map()->set_elements_kind(FAST_HOLEY_ELEMENTS);
     DCHECK_NE(fixed_array_map(), fixed_cow_array_map());
 
     ALLOCATE_VARSIZE_MAP(FIXED_ARRAY_TYPE, scope_info)
     ALLOCATE_VARSIZE_MAP(FIXED_ARRAY_TYPE, module_info)
+    ALLOCATE_VARSIZE_MAP(FIXED_ARRAY_TYPE, type_feedback_vector)
     ALLOCATE_PRIMITIVE_MAP(HEAP_NUMBER_TYPE, HeapNumber::kSize, heap_number,
                            Context::NUMBER_FUNCTION_INDEX)
     ALLOCATE_MAP(MUTABLE_HEAP_NUMBER_TYPE, HeapNumber::kSize,
                  mutable_heap_number)
     ALLOCATE_PRIMITIVE_MAP(SYMBOL_TYPE, Symbol::kSize, symbol,
                            Context::SYMBOL_FUNCTION_INDEX)
 #define ALLOCATE_SIMD128_MAP(TYPE, Type, type, lane_count, lane_type) \
   ALLOCATE_PRIMITIVE_MAP(SIMD128_VALUE_TYPE, Type::kSize, type,       \
                          Context::TYPE##_FUNCTION_INDEX)
     SIMD128_TYPES(ALLOCATE_SIMD128_MAP)
@@ skipping 508 matching lines @@
     // that all these functions will share the same invocation count, but
     // that shouldn't matter since we only use the invocation count to
     // relativize the absolute call counts, but we can only have call counts
     // if we have actual feedback slots.
     Handle<FixedArray> empty_type_feedback_vector = factory->NewFixedArray(
         TypeFeedbackVector::kReservedIndexCount, TENURED);
     empty_type_feedback_vector->set(TypeFeedbackVector::kMetadataIndex,
                                     empty_fixed_array());
     empty_type_feedback_vector->set(TypeFeedbackVector::kInvocationCountIndex,
                                     Smi::kZero);
+    empty_type_feedback_vector->set_map(type_feedback_vector_map());
     set_empty_type_feedback_vector(*empty_type_feedback_vector);
 
     // We use a canonical empty LiteralsArray for all functions that neither
     // have literals nor need a TypeFeedbackVector (besides the invocation
     // count special slot).
     Handle<FixedArray> empty_literals_array =
         factory->NewFixedArray(1, TENURED);
     empty_literals_array->set(0, *empty_type_feedback_vector);
     set_empty_literals_array(*empty_literals_array);
   }
@@ skipping 3755 matching lines @@
 }
 
 
 // static
 int Heap::GetStaticVisitorIdForMap(Map* map) {
   return StaticVisitorBase::GetVisitorId(map);
 }
 
 }  // namespace internal
 }  // namespace v8