[es6] Correct Function.prototype.apply, Reflect.construct and Reflect.apply.

src/x64/builtins-x64.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.
 
 #if V8_TARGET_ARCH_X64
 
 #include "src/code-factory.h"
 #include "src/codegen.h"
 #include "src/deoptimizer.h"
 #include "src/full-codegen/full-codegen.h"
@@ skipping 989 matching lines @@
     __ j(not_zero, &loop);              // While non-zero.
     __ DropUnderReturnAddress(1, rbx);  // Drop one slot under return address.
     __ decp(rax);  // One fewer argument (first argument is new receiver).
   }
 
   // 4. Call the callable.
   __ Jump(masm->isolate()->builtins()->Call(), RelocInfo::CODE_TARGET);
 }
 
 
-static void Generate_PushAppliedArguments(MacroAssembler* masm,
-                                          const int vectorOffset,
-                                          const int argumentsOffset,
-                                          const int indexOffset,
-                                          const int limitOffset) {
-  Register receiver = LoadDescriptor::ReceiverRegister();
-  Register key = LoadDescriptor::NameRegister();
-  Register slot = LoadDescriptor::SlotRegister();
-  Register vector = LoadWithVectorDescriptor::VectorRegister();
-
-  // Copy all arguments from the array to the stack.
-  Label entry, loop;
-  __ movp(key, Operand(rbp, indexOffset));
-  __ jmp(&entry);
-  __ bind(&loop);
-  __ movp(receiver, Operand(rbp, argumentsOffset));  // load arguments
-
-  // Use inline caching to speed up access to arguments.
-  int slot_index = TypeFeedbackVector::PushAppliedArgumentsIndex();
-  __ Move(slot, Smi::FromInt(slot_index));
-  __ movp(vector, Operand(rbp, vectorOffset));
-  Handle<Code> ic =
-      KeyedLoadICStub(masm->isolate(), LoadICState(kNoExtraICState)).GetCode();
-  __ Call(ic, RelocInfo::CODE_TARGET);
-  // It is important that we do not have a test instruction after the
-  // call.  A test instruction after the call is used to indicate that
-  // we have generated an inline version of the keyed load.  In this
-  // case, we know that we are not generating a test instruction next.
-
-  // Push the nth argument.
-  __ Push(rax);
-
-  // Update the index on the stack and in register key.
-  __ movp(key, Operand(rbp, indexOffset));
-  __ SmiAddConstant(key, key, Smi::FromInt(1));
-  __ movp(Operand(rbp, indexOffset), key);
-
-  __ bind(&entry);
-  __ cmpp(key, Operand(rbp, limitOffset));
-  __ j(not_equal, &loop);
-
-  // On exit, the pushed arguments count is in rax, untagged
-  __ SmiToInteger64(rax, key);
-}
-
-
-// Used by FunctionApply and ReflectApply
-static void Generate_ApplyHelper(MacroAssembler* masm, bool targetIsArgument) {
-  const int kFormalParameters = targetIsArgument ? 3 : 2;
-  const int kStackSize = kFormalParameters + 1;
-
-  // Stack at entry:
-  // rsp     : return address
-  // rsp[8]  : arguments
-  // rsp[16] : receiver ("this")
-  // rsp[24] : function
-  {
-    FrameScope frame_scope(masm, StackFrame::INTERNAL);
-    // Stack frame:
-    // rbp     : Old base pointer
-    // rbp[8]  : return address
-    // rbp[16] : function arguments
-    // rbp[24] : receiver
-    // rbp[32] : function
-    static const int kArgumentsOffset = kFPOnStackSize + kPCOnStackSize;
-    static const int kReceiverOffset = kArgumentsOffset + kPointerSize;
-    static const int kFunctionOffset = kReceiverOffset + kPointerSize;
-    static const int kVectorOffset =
-        InternalFrameConstants::kCodeOffset - 1 * kPointerSize;
-
-    // Push the vector.
-    __ movp(rdi, FieldOperand(rdi, JSFunction::kSharedFunctionInfoOffset));
-    __ movp(rdi, FieldOperand(rdi, SharedFunctionInfo::kFeedbackVectorOffset));
-    __ Push(rdi);
-
-    __ Push(Operand(rbp, kFunctionOffset));
-    __ Push(Operand(rbp, kArgumentsOffset));
-    if (targetIsArgument) {
-      __ InvokeBuiltin(Context::REFLECT_APPLY_PREPARE_BUILTIN_INDEX,
-                       CALL_FUNCTION);
-    } else {
-      __ InvokeBuiltin(Context::APPLY_PREPARE_BUILTIN_INDEX, CALL_FUNCTION);
+void Builtins::Generate_FunctionApply(MacroAssembler* masm) {
+  // ----------- S t a t e -------------
+  //  -- rax     : argc
+  //  -- rsp[0]  : return address
+  //  -- rsp[8]  : argArray
+  //  -- rsp[16] : thisArg
+  //  -- rsp[24] : receiver
+  // -----------------------------------
+
+  // 1. Load receiver into rdi, argArray into rax (if present), remove all
+  // arguments from the stack (including the receiver), and push thisArg (if
+  // present) instead.
+  {
+    Label no_arg_array, no_this_arg;
+    StackArgumentsAccessor args(rsp, rax);
+    __ LoadRoot(rdx, Heap::kUndefinedValueRootIndex);
+    __ movp(rbx, rdx);
+    __ movp(rdi, args.GetReceiverOperand());
+    __ testp(rax, rax);
+    __ j(zero, &no_this_arg, Label::kNear);
+    {
+      __ movp(rdx, args.GetArgumentOperand(1));
+      __ cmpp(rax, Immediate(1));
+      __ j(equal, &no_arg_array, Label::kNear);
+      __ movp(rbx, args.GetArgumentOperand(2));
+      __ bind(&no_arg_array);
     }
-
-    Generate_CheckStackOverflow(masm, kRaxIsSmiTagged);
-
-    // Push current index and limit, and receiver.
-    const int kLimitOffset = kVectorOffset - 1 * kPointerSize;
-    const int kIndexOffset = kLimitOffset - 1 * kPointerSize;
-    __ Push(rax);                            // limit
-    __ Push(Immediate(0));                   // index
-    __ Push(Operand(rbp, kReceiverOffset));  // receiver
-
-    // Loop over the arguments array, pushing each value to the stack
-    Generate_PushAppliedArguments(masm, kVectorOffset, kArgumentsOffset,
-                                  kIndexOffset, kLimitOffset);
-
-    // Call the callable.
-    // TODO(bmeurer): This should be a tail call according to ES6.
-    __ movp(rdi, Operand(rbp, kFunctionOffset));
-    __ Call(masm->isolate()->builtins()->Call(), RelocInfo::CODE_TARGET);
-
-    // Leave internal frame.
-  }
-  __ ret(kStackSize * kPointerSize);  // remove this, receiver, and arguments
-}
-
-
-// Used by ReflectConstruct
-static void Generate_ConstructHelper(MacroAssembler* masm) {
-  const int kFormalParameters = 3;
-  const int kStackSize = kFormalParameters + 1;
-
-  // Stack at entry:
-  // rsp     : return address
-  // rsp[8]  : new target
-  // rsp[16] : arguments
-  // rsp[24] : constructor
-  {
-    FrameScope frame_scope(masm, StackFrame::INTERNAL);
-    // Stack frame:
-    // rbp     : Old base pointer
-    // rbp[8]  : return address
-    // rbp[16] : new target
-    // rbp[24] : arguments
-    // rbp[32] : constructor
-    static const int kNewTargetOffset = kFPOnStackSize + kPCOnStackSize;
-    static const int kArgumentsOffset = kNewTargetOffset + kPointerSize;
-    static const int kFunctionOffset = kArgumentsOffset + kPointerSize;
-
-    static const int kVectorOffset =
-        InternalFrameConstants::kCodeOffset - 1 * kPointerSize;
-
-    // Push the vector.
-    __ movp(rdi, FieldOperand(rdi, JSFunction::kSharedFunctionInfoOffset));
-    __ movp(rdi, FieldOperand(rdi, SharedFunctionInfo::kFeedbackVectorOffset));
-    __ Push(rdi);
-
-    // If newTarget is not supplied, set it to constructor
-    Label validate_arguments;
-    __ movp(rax, Operand(rbp, kNewTargetOffset));
-    __ CompareRoot(rax, Heap::kUndefinedValueRootIndex);
-    __ j(not_equal, &validate_arguments, Label::kNear);
-    __ movp(rax, Operand(rbp, kFunctionOffset));
-    __ movp(Operand(rbp, kNewTargetOffset), rax);
-
-    // Validate arguments
-    __ bind(&validate_arguments);
-    __ Push(Operand(rbp, kFunctionOffset));
-    __ Push(Operand(rbp, kArgumentsOffset));
-    __ Push(Operand(rbp, kNewTargetOffset));
-    __ InvokeBuiltin(Context::REFLECT_CONSTRUCT_PREPARE_BUILTIN_INDEX,
-                     CALL_FUNCTION);
-
-    Generate_CheckStackOverflow(masm, kRaxIsSmiTagged);
-
-    // Push current index and limit.
-    const int kLimitOffset = kVectorOffset - 1 * kPointerSize;
-    const int kIndexOffset = kLimitOffset - 1 * kPointerSize;
-    __ Push(rax);  // limit
-    __ Push(Immediate(0));  // index
-    // Push the constructor function as callee.
-    __ Push(Operand(rbp, kFunctionOffset));
-
-    // Loop over the arguments array, pushing each value to the stack
-    Generate_PushAppliedArguments(masm, kVectorOffset, kArgumentsOffset,
-                                  kIndexOffset, kLimitOffset);
-
-    // Use undefined feedback vector
-    __ LoadRoot(rbx, Heap::kUndefinedValueRootIndex);
-    __ movp(rdi, Operand(rbp, kFunctionOffset));
-    __ movp(rdx, Operand(rbp, kNewTargetOffset));
-
-    // Call the function.
-    __ Call(masm->isolate()->builtins()->Construct(), RelocInfo::CODE_TARGET);
-
-    // Leave internal frame.
-  }
-  // remove this, target, arguments and newTarget
-  __ ret(kStackSize * kPointerSize);
-}
-
-
-void Builtins::Generate_FunctionApply(MacroAssembler* masm) {
-  Generate_ApplyHelper(masm, false);
+    __ bind(&no_this_arg);
+    __ PopReturnAddressTo(rcx);
+    __ leap(rsp, Operand(rsp, rax, times_pointer_size, kPointerSize));
+    __ Push(rdx);
+    __ PushReturnAddressFrom(rcx);
+    __ movp(rax, rbx);
+  }
+
+  // ----------- S t a t e -------------
+  //  -- rax     : argArray
+  //  -- rdi     : receiver
+  //  -- rsp[0]  : return address
+  //  -- rsp[8]  : thisArg
+  // -----------------------------------
+
+  // 2. Make sure the receiver is actually callable.
+  Label receiver_not_callable;
+  __ JumpIfSmi(rdi, &receiver_not_callable, Label::kNear);
+  __ movp(rcx, FieldOperand(rdi, HeapObject::kMapOffset));
+  __ testb(FieldOperand(rcx, Map::kBitFieldOffset),
+           Immediate(1 << Map::kIsCallable));
+  __ j(zero, &receiver_not_callable, Label::kNear);
+
+  // 3. Tail call with no arguments if argArray is null or undefined.
+  Label no_arguments;
+  __ JumpIfRoot(rax, Heap::kNullValueRootIndex, &no_arguments, Label::kNear);
+  __ JumpIfRoot(rax, Heap::kUndefinedValueRootIndex, &no_arguments,
+                Label::kNear);
+
+  // 4a. Apply the receiver to the given argArray (passing undefined for
+  // new.target).
+  __ LoadRoot(rdx, Heap::kUndefinedValueRootIndex);
+  __ Jump(masm->isolate()->builtins()->Apply(), RelocInfo::CODE_TARGET);
+
+  // 4b. The argArray is either null or undefined, so we tail call without any
+  // arguments to the receiver.
+  __ bind(&no_arguments);
+  {
+    __ Set(rax, 0);
+    __ Jump(masm->isolate()->builtins()->Call(), RelocInfo::CODE_TARGET);
+  }
+
+  // 4c. The receiver is not callable, throw an appropriate TypeError.
+  __ bind(&receiver_not_callable);
+  {
+    StackArgumentsAccessor args(rsp, 0);
+    __ movp(args.GetReceiverOperand(), rdi);
+    __ TailCallRuntime(Runtime::kThrowApplyNonFunction, 1, 1);
+  }
 }
 
 
 void Builtins::Generate_ReflectApply(MacroAssembler* masm) {
-  Generate_ApplyHelper(masm, true);
+  // ----------- S t a t e -------------
+  //  -- rax     : argc
+  //  -- rsp[0]  : return address
+  //  -- rsp[8]  : argumentsList
+  //  -- rsp[16] : thisArgument
+  //  -- rsp[24] : target
+  //  -- rsp[32] : receiver
+  // -----------------------------------
+
+  // 1. Load target into rdi (if present), argumentsList into rax (if present),
+  // remove all arguments from the stack (including the receiver), and push
+  // thisArgument (if present) instead.
+  {
+    Label done;
+    StackArgumentsAccessor args(rsp, rax);
+    __ LoadRoot(rdi, Heap::kUndefinedValueRootIndex);
+    __ movp(rdx, rdi);
+    __ movp(rbx, rdi);
+    __ cmpp(rax, Immediate(1));
+    __ j(below, &done, Label::kNear);
+    __ movp(rdi, args.GetArgumentOperand(1));  // target
+    __ j(equal, &done, Label::kNear);
+    __ movp(rdx, args.GetArgumentOperand(2));  // thisArgument
+    __ cmpp(rax, Immediate(3));
+    __ j(below, &done, Label::kNear);
+    __ movp(rbx, args.GetArgumentOperand(3));  // argumentsList
+    __ bind(&done);
+    __ PopReturnAddressTo(rcx);
+    __ leap(rsp, Operand(rsp, rax, times_pointer_size, kPointerSize));
+    __ Push(rdx);
+    __ PushReturnAddressFrom(rcx);
+    __ movp(rax, rbx);
+  }
+
+  // ----------- S t a t e -------------
+  //  -- rax     : argumentsList
+  //  -- rdi     : target
+  //  -- rsp[0]  : return address
+  //  -- rsp[8]  : thisArgument
+  // -----------------------------------
+
+  // 2. Make sure the target is actually callable.
+  Label target_not_callable;
+  __ JumpIfSmi(rdi, &target_not_callable, Label::kNear);
+  __ movp(rcx, FieldOperand(rdi, HeapObject::kMapOffset));
+  __ testb(FieldOperand(rcx, Map::kBitFieldOffset),
+           Immediate(1 << Map::kIsCallable));
+  __ j(zero, &target_not_callable, Label::kNear);
+
+  // 3a. Apply the target to the given argumentsList (passing undefined for
+  // new.target).
+  __ LoadRoot(rdx, Heap::kUndefinedValueRootIndex);
+  __ Jump(masm->isolate()->builtins()->Apply(), RelocInfo::CODE_TARGET);
+
+  // 3b. The target is not callable, throw an appropriate TypeError.
+  __ bind(&target_not_callable);
+  {
+    StackArgumentsAccessor args(rsp, 0);
+    __ movp(args.GetReceiverOperand(), rdi);
+    __ TailCallRuntime(Runtime::kThrowApplyNonFunction, 1, 1);
+  }
 }
 
 
 void Builtins::Generate_ReflectConstruct(MacroAssembler* masm) {
-  Generate_ConstructHelper(masm);
-}
-
-
+  // ----------- S t a t e -------------
+  //  -- rax     : argc
+  //  -- rsp[0]  : return address
+  //  -- rsp[8]  : new.target (optional)
+  //  -- rsp[16] : argumentsList
+  //  -- rsp[24] : target
+  //  -- rsp[32] : receiver
+  // -----------------------------------
+
+  // 1. Load target into rdi (if present), argumentsList into rax (if present),
+  // new.target into rdx (if present, otherwise use target), remove all
+  // arguments from the stack (including the receiver), and push thisArgument
+  // (if present) instead.
+  {
+    Label done;
+    StackArgumentsAccessor args(rsp, rax);
+    __ LoadRoot(rdi, Heap::kUndefinedValueRootIndex);
+    __ movp(rdx, rdi);
+    __ movp(rbx, rdi);
+    __ cmpp(rax, Immediate(1));
+    __ j(below, &done, Label::kNear);
+    __ movp(rdi, args.GetArgumentOperand(1));  // target
+    __ movp(rdx, rdi);                         // new.target defaults to target
+    __ j(equal, &done, Label::kNear);
+    __ movp(rbx, args.GetArgumentOperand(2));  // argumentsList
+    __ cmpp(rax, Immediate(3));
+    __ j(below, &done, Label::kNear);
+    __ movp(rdx, args.GetArgumentOperand(3));  // new.target
+    __ bind(&done);
+    __ PopReturnAddressTo(rcx);
+    __ leap(rsp, Operand(rsp, rax, times_pointer_size, kPointerSize));
+    __ PushRoot(Heap::kUndefinedValueRootIndex);
+    __ PushReturnAddressFrom(rcx);
+    __ movp(rax, rbx);
+  }
+
+  // ----------- S t a t e -------------
+  //  -- rax     : argumentsList
+  //  -- rdx     : new.target
+  //  -- rdi     : target
+  //  -- rsp[0]  : return address
+  //  -- rsp[8]  : receiver (undefined)
+  // -----------------------------------
+
+  // 2. Make sure the target is actually a constructor.
+  Label target_not_constructor;
+  __ JumpIfSmi(rdi, &target_not_constructor, Label::kNear);
+  __ movp(rcx, FieldOperand(rdi, HeapObject::kMapOffset));
+  __ testb(FieldOperand(rcx, Map::kBitFieldOffset),
+           Immediate(1 << Map::kIsConstructor));
+  __ j(zero, &target_not_constructor, Label::kNear);
+
+  // 3. Make sure the target is actually a constructor.
+  Label new_target_not_constructor;
+  __ JumpIfSmi(rdx, &new_target_not_constructor, Label::kNear);
+  __ movp(rcx, FieldOperand(rdx, HeapObject::kMapOffset));
+  __ testb(FieldOperand(rcx, Map::kBitFieldOffset),
+           Immediate(1 << Map::kIsConstructor));
+  __ j(zero, &new_target_not_constructor, Label::kNear);
+
+  // 4a. Construct the target with the given new.target and argumentsList.
+  __ Jump(masm->isolate()->builtins()->Apply(), RelocInfo::CODE_TARGET);
+
+  // 4b. The target is not a constructor, throw an appropriate TypeError.
+  __ bind(&target_not_constructor);
+  {
+    StackArgumentsAccessor args(rsp, 0);
+    __ movp(args.GetReceiverOperand(), rdi);
+    __ TailCallRuntime(Runtime::kThrowCalledNonCallable, 1, 1);
+  }
+
+  // 4c. The new.target is not a constructor, throw an appropriate TypeError.
+  __ bind(&new_target_not_constructor);
+  {
+    StackArgumentsAccessor args(rsp, 0);
+    __ movp(args.GetReceiverOperand(), rdx);
+    __ TailCallRuntime(Runtime::kThrowCalledNonCallable, 1, 1);
+  }
+}
+
+
 void Builtins::Generate_InternalArrayCode(MacroAssembler* masm) {
   // ----------- S t a t e -------------
   //  -- rax    : argc
   //  -- rsp[0] : return address
   //  -- rsp[8] : last argument
   // -----------------------------------
   Label generic_array_code;
 
   // Get the InternalArray function.
   __ LoadNativeContextSlot(Context::INTERNAL_ARRAY_FUNCTION_INDEX, rdi);
@@ skipping 388 matching lines @@
   __ bind(&stack_overflow);
   {
     FrameScope frame(masm, StackFrame::MANUAL);
     __ CallRuntime(Runtime::kThrowStackOverflow, 0);
     __ int3();
   }
 }
 
 
 // static
+void Builtins::Generate_Apply(MacroAssembler* masm) {
+  // ----------- S t a t e -------------
+  //  -- rax    : argumentsList
+  //  -- rdi    : target
+  //  -- rdx    : new.target (checked to be constructor or undefined)
+  //  -- rsp[0] : return address.
+  //  -- rsp[8] : thisArgument
+  // -----------------------------------
+
+  // Create the list of arguments from the array-like argumentsList.
+  {
+    Label create_arguments, create_array, create_runtime, done_create;
+    __ JumpIfSmi(rax, &create_runtime);
+
+    // Load the map of argumentsList into rcx.
+    __ movp(rcx, FieldOperand(rax, HeapObject::kMapOffset));
+
+    // Load native context into rbx.
+    __ movp(rbx, NativeContextOperand());
+
+    // Check if argumentsList is an (unmodified) arguments object.
+    __ cmpp(rcx, ContextOperand(rbx, Context::SLOPPY_ARGUMENTS_MAP_INDEX));
+    __ j(equal, &create_arguments);
+    __ cmpp(rcx, ContextOperand(rbx, Context::STRICT_ARGUMENTS_MAP_INDEX));
+    __ j(equal, &create_arguments);
+
+    // Check if argumentsList is a fast JSArray.
+    __ CmpInstanceType(rcx, JS_ARRAY_TYPE);
+    __ j(equal, &create_array);
+
+    // Ask the runtime to create the list (actually a FixedArray).
+    __ bind(&create_runtime);
+    {
+      FrameScope scope(masm, StackFrame::INTERNAL);
+      __ Push(rdi);
+      __ Push(rdx);
+      __ Push(rax);
+      __ CallRuntime(Runtime::kCreateListFromArrayLike, 1);
+      __ Pop(rdx);
+      __ Pop(rdi);
+      __ SmiToInteger32(rbx, FieldOperand(rax, FixedArray::kLengthOffset));
+    }
+    __ jmp(&done_create);
+
+    // Try to create the list from an arguments object.
+    __ bind(&create_arguments);
+    __ movp(rbx,
+            FieldOperand(rax, JSObject::kHeaderSize +
+                                  Heap::kArgumentsLengthIndex * kPointerSize));
+    __ movp(rcx, FieldOperand(rax, JSObject::kElementsOffset));
+    __ cmpp(rbx, FieldOperand(rcx, FixedArray::kLengthOffset));
+    __ j(not_equal, &create_runtime);
+    __ SmiToInteger32(rbx, rbx);
+    __ movp(rax, rcx);
+    __ jmp(&done_create);
+
+    // Try to create the list from a JSArray object.
+    __ bind(&create_array);
+    __ movzxbp(rcx, FieldOperand(rcx, Map::kBitField2Offset));
+    __ DecodeField<Map::ElementsKindBits>(rcx);
+    STATIC_ASSERT(FAST_SMI_ELEMENTS == 0);
+    STATIC_ASSERT(FAST_HOLEY_SMI_ELEMENTS == 1);
+    STATIC_ASSERT(FAST_ELEMENTS == 2);
+    __ cmpl(rcx, Immediate(FAST_ELEMENTS));
+    __ j(above, &create_runtime);
+    __ cmpl(rcx, Immediate(FAST_HOLEY_SMI_ELEMENTS));
+    __ j(equal, &create_runtime);
+    __ SmiToInteger32(rbx, FieldOperand(rax, JSArray::kLengthOffset));
+    __ movp(rax, FieldOperand(rax, JSArray::kElementsOffset));
+
+    __ bind(&done_create);
+  }
+
+  // Check for stack overflow.
+  {
+    // Check the stack for overflow. We are not trying to catch interruptions
+    // (i.e. debug break and preemption) here, so check the "real stack limit".
+    Label done;
+    __ LoadRoot(kScratchRegister, Heap::kRealStackLimitRootIndex);
+    __ movp(rcx, rsp);
+    // Make rcx the space we have left. The stack might already be overflowed
+    // here which will cause rcx to become negative.
+    __ subp(rcx, kScratchRegister);
+    __ sarp(rcx, Immediate(kPointerSizeLog2));
+    // Check if the arguments will overflow the stack.
+    __ cmpp(rcx, rbx);
+    __ j(greater, &done, Label::kNear);  // Signed comparison.
+    __ TailCallRuntime(Runtime::kThrowStackOverflow, 1, 1);
+    __ bind(&done);
+  }
+
+  // ----------- S t a t e -------------
+  //  -- rdi    : target
+  //  -- rax    : args (a FixedArray built from argumentsList)
+  //  -- rbx    : len (number of elements to push from args)
+  //  -- rdx    : new.target (checked to be constructor or undefined)
+  //  -- rsp[0] : return address.
+  //  -- rsp[8] : thisArgument
+  // -----------------------------------
+
+  // Push arguments onto the stack (thisArgument is already on the stack).
+  {
+    __ PopReturnAddressTo(r8);
+    __ Set(rcx, 0);
+    Label done, loop;
+    __ bind(&loop);
+    __ cmpl(rcx, rbx);
+    __ j(equal, &done, Label::kNear);
+    __ Push(
+        FieldOperand(rax, rcx, times_pointer_size, FixedArray::kHeaderSize));
+    __ incl(rcx);
+    __ jmp(&loop);
+    __ bind(&done);
+    __ PushReturnAddressFrom(r8);
+    __ Move(rax, rcx);
+  }
+
+  // Dispatch to Call or Construct depending on whether new.target is undefined.
+  {
+    __ CompareRoot(rdx, Heap::kUndefinedValueRootIndex);
+    __ j(equal, masm->isolate()->builtins()->Call(), RelocInfo::CODE_TARGET);
+    __ Jump(masm->isolate()->builtins()->Construct(), RelocInfo::CODE_TARGET);
+  }
+}
+
+
+// static
 void Builtins::Generate_CallFunction(MacroAssembler* masm,
                                      ConvertReceiverMode mode) {
   // ----------- S t a t e -------------
   //  -- rax : the number of arguments (not including the receiver)
   //  -- rdi : the function to call (checked to be a JSFunction)
   // -----------------------------------
   StackArgumentsAccessor args(rsp, rax);
   __ AssertFunction(rdi);
 
   // ES6 section 9.2.1 [[Call]] ( thisArgument, argumentsList)
@@ skipping 425 matching lines @@
   __ ret(0);
 }
 
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_X64