Count closures using the feedback vector cell map, specialize if count==1.

src/code-stub-assembler.h

 // Copyright 2016 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_CODE_STUB_ASSEMBLER_H_
 #define V8_CODE_STUB_ASSEMBLER_H_
 
 #include <functional>
 
 #include "src/compiler/code-assembler.h"
@@ skipping 16 matching lines @@
   V(BooleanMap, BooleanMap)                           \
   V(CodeMap, CodeMap)                                 \
   V(empty_string, EmptyString)                        \
   V(EmptyFixedArray, EmptyFixedArray)                 \
   V(FalseValue, False)                                \
   V(FixedArrayMap, FixedArrayMap)                     \
   V(FixedCOWArrayMap, FixedCOWArrayMap)               \
   V(FixedDoubleArrayMap, FixedDoubleArrayMap)         \
   V(FunctionTemplateInfoMap, FunctionTemplateInfoMap) \
   V(HeapNumberMap, HeapNumberMap)                     \
+  V(NoClosuresCellMap, NoClosuresCellMap)             \
+  V(OneClosureCellMap, OneClosureCellMap)             \
+  V(ManyClosuresCellMap, ManyClosuresCellMap)         \
   V(MinusZeroValue, MinusZero)                        \
   V(NanValue, Nan)                                    \
   V(NullValue, Null)                                  \
   V(SymbolMap, SymbolMap)                             \
   V(TheHoleValue, TheHole)                            \
   V(TrueValue, True)                                  \
   V(Tuple2Map, Tuple2Map)                             \
   V(Tuple3Map, Tuple3Map)                             \
   V(UndefinedValue, Undefined)
 
@@ skipping 1278 matching lines @@
   }
 #else
 #define CSA_SLOW_ASSERT(csa, x) ((void)0)
 #endif
 
 DEFINE_OPERATORS_FOR_FLAGS(CodeStubAssembler::AllocationFlags);
 
 }  // namespace internal
 }  // namespace v8
 #endif  // V8_CODE_STUB_ASSEMBLER_H_