[builtins] Migrate String.fromCharCode to TurboFan code stub.

src/builtins.h

 // Copyright 2011 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_BUILTINS_H_
 #define V8_BUILTINS_H_
 
 #include "src/base/flags.h"
 #include "src/handles.h"
 
@@ skipping 153 matching lines @@
   V(ReflectGet, kNone)                                         \
   V(ReflectGetOwnPropertyDescriptor, kNone)                    \
   V(ReflectGetPrototypeOf, kNone)                              \
   V(ReflectHas, kNone)                                         \
   V(ReflectIsExtensible, kNone)                                \
   V(ReflectOwnKeys, kNone)                                     \
   V(ReflectPreventExtensions, kNone)                           \
   V(ReflectSet, kNone)                                         \
   V(ReflectSetPrototypeOf, kNone)                              \
                                                                \
-  V(StringFromCharCode, kNone)                                 \
   V(StringPrototypeTrim, kNone)                                \
   V(StringPrototypeTrimLeft, kNone)                            \
   V(StringPrototypeTrimRight, kNone)                           \
                                                                \
   V(SymbolConstructor, kNone)                                  \
   V(SymbolConstructor_ConstructStub, kTarget)                  \
                                                                \
   V(HandleApiCall, kTargetAndNewTarget)                        \
   V(HandleApiCallAsFunction, kNone)                            \
   V(HandleApiCallAsConstructor, kNone)                         \
@@ skipping 138 matching lines @@
   V(GeneratorPrototypeReturn, 2)     \
   V(GeneratorPrototypeThrow, 2)      \
   V(MathCeil, 2)                     \
   V(MathClz32, 2)                    \
   V(MathFloor, 2)                    \
   V(MathRound, 2)                    \
   V(MathSqrt, 2)                     \
   V(MathTrunc, 2)                    \
   V(ObjectHasOwnProperty, 2)         \
   V(ArrayIsArray, 2)                 \
+  V(StringFromCharCode, 2)           \
   V(StringPrototypeCharAt, 2)        \
   V(StringPrototypeCharCodeAt, 2)    \
   V(AtomicsLoad, 3)                  \
   V(AtomicsStore, 4)
 
 // Define list of builtin handlers implemented in assembly.
 #define BUILTIN_LIST_H(V)                    \
   V(LoadIC_Slow,             LOAD_IC)        \
   V(KeyedLoadIC_Slow,        KEYED_LOAD_IC)  \
   V(StoreIC_Slow,            STORE_IC)       \
@@ skipping 304 matching lines @@
   static void Generate_GeneratorPrototypeReturn(CodeStubAssembler* assembler);
   // ES6 section 25.3.1.4 Generator.prototype.throw ( exception )
   static void Generate_GeneratorPrototypeThrow(CodeStubAssembler* assembler);
 
   // ES6 section 19.1.3.2 Object.prototype.hasOwnProperty
   static void Generate_ObjectHasOwnProperty(CodeStubAssembler* assembler);
 
   // ES6 section 22.1.2.2 Array.isArray
   static void Generate_ArrayIsArray(CodeStubAssembler* assembler);
 
+  // ES6 section 21.1.2.1 String.fromCharCode ( ...codeUnits )
+  static void Generate_StringFromCharCode(CodeStubAssembler* assembler);
   // ES6 section 21.1.3.1 String.prototype.charAt ( pos )
   static void Generate_StringPrototypeCharAt(CodeStubAssembler* assembler);
   // ES6 section 21.1.3.2 String.prototype.charCodeAt ( pos )
   static void Generate_StringPrototypeCharCodeAt(CodeStubAssembler* assembler);
 
   static void Generate_StringConstructor(MacroAssembler* masm);
   static void Generate_StringConstructor_ConstructStub(MacroAssembler* masm);
   static void Generate_OnStackReplacement(MacroAssembler* masm);
   static void Generate_InterruptCheck(MacroAssembler* masm);
   static void Generate_StackCheck(MacroAssembler* masm);
@@ skipping 34 matching lines @@
   friend class BuiltinFunctionTable;
   friend class Isolate;
 
   DISALLOW_COPY_AND_ASSIGN(Builtins);
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_BUILTINS_H_