[stubs] Simplify the ArrayConstructorStub.

Remove the special side channel from the CallICStub to the
ArrayConstructorStub and make the CallICStub always use the
general entry point.

R=yangguo@chromium.org

Review-Url: https://codereview.chromium.org/2405203002
Cr-Commit-Position: refs/heads/master@{#40162}

src/arm/code-stubs-arm.cc

@@ -1792,14 +1792,13 @@ void CallICStub::HandleArrayCase(MacroAssembler* masm, Label* miss) {
   __ cmp(r1, r5);
   __ b(ne, miss);
 
-  __ mov(r0, Operand(arg_count()));
-
   // Increment the call count for monomorphic function calls.
   IncrementCallCount(masm, r2, r3);
 
   __ mov(r2, r4);
   __ mov(r3, r1);
-  ArrayConstructorStub stub(masm->isolate(), arg_count());
+  __ mov(r0, Operand(arg_count()));
+  ArrayConstructorStub stub(masm->isolate());
   __ TailCallStub(&stub);
 }
 
@@ -3706,30 +3705,19 @@ void CommonArrayConstructorStub::GenerateStubsAheadOfTime(Isolate* isolate) {
 void ArrayConstructorStub::GenerateDispatchToArrayStub(
     MacroAssembler* masm,
     AllocationSiteOverrideMode mode) {
-  if (argument_count() == ANY) {
-    Label not_zero_case, not_one_case;
-    __ tst(r0, r0);
-    __ b(ne, &not_zero_case);
-    CreateArrayDispatch<ArrayNoArgumentConstructorStub>(masm, mode);
-
-    __ bind(&not_zero_case);
-    __ cmp(r0, Operand(1));
-    __ b(gt, &not_one_case);
-    CreateArrayDispatchOneArgument(masm, mode);
-
-    __ bind(&not_one_case);
-    ArrayNArgumentsConstructorStub stub(masm->isolate());
-    __ TailCallStub(&stub);
-  } else if (argument_count() == NONE) {
-    CreateArrayDispatch<ArrayNoArgumentConstructorStub>(masm, mode);
-  } else if (argument_count() == ONE) {
-    CreateArrayDispatchOneArgument(masm, mode);
-  } else if (argument_count() == MORE_THAN_ONE) {
-    ArrayNArgumentsConstructorStub stub(masm->isolate());
-    __ TailCallStub(&stub);
-  } else {
-    UNREACHABLE();
-  }
+  Label not_zero_case, not_one_case;
+  __ tst(r0, r0);
+  __ b(ne, &not_zero_case);
+  CreateArrayDispatch<ArrayNoArgumentConstructorStub>(masm, mode);
+
+  __ bind(&not_zero_case);
+  __ cmp(r0, Operand(1));
+  __ b(gt, &not_one_case);
+  CreateArrayDispatchOneArgument(masm, mode);
+
+  __ bind(&not_one_case);
+  ArrayNArgumentsConstructorStub stub(masm->isolate());
+  __ TailCallStub(&stub);
 }
 
 
@@ -3781,21 +3769,8 @@ void ArrayConstructorStub::Generate(MacroAssembler* masm) {
   GenerateDispatchToArrayStub(masm, DISABLE_ALLOCATION_SITES);
 
   __ bind(&subclassing);
-  switch (argument_count()) {
-    case ANY:
-    case MORE_THAN_ONE:
-      __ str(r1, MemOperand(sp, r0, LSL, kPointerSizeLog2));
-      __ add(r0, r0, Operand(3));
-      break;
-    case NONE:
-      __ str(r1, MemOperand(sp, 0 * kPointerSize));
-      __ mov(r0, Operand(3));
-      break;
-    case ONE:
-      __ str(r1, MemOperand(sp, 1 * kPointerSize));
-      __ mov(r0, Operand(4));
-      break;
-  }
+  __ str(r1, MemOperand(sp, r0, LSL, kPointerSizeLog2));
+  __ add(r0, r0, Operand(3));
   __ Push(r3, r2);
   __ JumpToExternalReference(ExternalReference(Runtime::kNewArray, isolate()));
 }

src/arm64/code-stubs-arm64.cc

@@ -2011,8 +2011,6 @@ void CallICStub::HandleArrayCase(MacroAssembler* masm, Label* miss) {
   __ Cmp(function, scratch);
   __ B(ne, miss);
 
-  __ Mov(x0, Operand(arg_count()));
-
   // Increment the call count for monomorphic function calls.
   IncrementCallCount(masm, feedback_vector, index);
 
@@ -2021,7 +2019,8 @@ void CallICStub::HandleArrayCase(MacroAssembler* masm, Label* miss) {
   Register new_target_arg = index;
   __ Mov(allocation_site_arg, allocation_site);
   __ Mov(new_target_arg, function);
-  ArrayConstructorStub stub(masm->isolate(), arg_count());
+  __ Mov(x0, Operand(arg_count()));
+  ArrayConstructorStub stub(masm->isolate());
   __ TailCallStub(&stub);
 }
 
@@ -3895,33 +3894,22 @@ void ArrayConstructorStub::GenerateDispatchToArrayStub(
     MacroAssembler* masm,
     AllocationSiteOverrideMode mode) {
   Register argc = x0;
-  if (argument_count() == ANY) {
-    Label zero_case, n_case;
-    __ Cbz(argc, &zero_case);
-    __ Cmp(argc, 1);
-    __ B(ne, &n_case);
-
-    // One argument.
-    CreateArrayDispatchOneArgument(masm, mode);
-
-    __ Bind(&zero_case);
-    // No arguments.
-    CreateArrayDispatch<ArrayNoArgumentConstructorStub>(masm, mode);
-
-    __ Bind(&n_case);
-    // N arguments.
-    ArrayNArgumentsConstructorStub stub(masm->isolate());
-    __ TailCallStub(&stub);
-  } else if (argument_count() == NONE) {
-    CreateArrayDispatch<ArrayNoArgumentConstructorStub>(masm, mode);
-  } else if (argument_count() == ONE) {
-    CreateArrayDispatchOneArgument(masm, mode);
-  } else if (argument_count() == MORE_THAN_ONE) {
-    ArrayNArgumentsConstructorStub stub(masm->isolate());
-    __ TailCallStub(&stub);
-  } else {
-    UNREACHABLE();
-  }
+  Label zero_case, n_case;
+  __ Cbz(argc, &zero_case);
+  __ Cmp(argc, 1);
+  __ B(ne, &n_case);
+
+  // One argument.
+  CreateArrayDispatchOneArgument(masm, mode);
+
+  __ Bind(&zero_case);
+  // No arguments.
+  CreateArrayDispatch<ArrayNoArgumentConstructorStub>(masm, mode);
+
+  __ Bind(&n_case);
+  // N arguments.
+  ArrayNArgumentsConstructorStub stub(masm->isolate());
+  __ TailCallStub(&stub);
 }
 
 
@@ -3981,21 +3969,8 @@ void ArrayConstructorStub::Generate(MacroAssembler* masm) {
 
   // Subclassing support.
   __ Bind(&subclassing);
-  switch (argument_count()) {
-    case ANY:
-    case MORE_THAN_ONE:
-      __ Poke(constructor, Operand(x0, LSL, kPointerSizeLog2));
-      __ Add(x0, x0, Operand(3));
-      break;
-    case NONE:
-      __ Poke(constructor, 0 * kPointerSize);
-      __ Mov(x0, Operand(3));
-      break;
-    case ONE:
-      __ Poke(constructor, 1 * kPointerSize);
-      __ Mov(x0, Operand(4));
-      break;
-  }
+  __ Poke(constructor, Operand(x0, LSL, kPointerSizeLog2));
+  __ Add(x0, x0, Operand(3));
   __ Push(new_target, allocation_site);
   __ JumpToExternalReference(ExternalReference(Runtime::kNewArray, isolate()));
 }

src/code-stubs.cc

@@ -2692,26 +2692,6 @@ void StoreFastElementStub::GenerateAheadOfTime(Isolate* isolate) {
   }
 }
 
-void ArrayConstructorStub::PrintName(std::ostream& os) const {  // NOLINT
-  os << "ArrayConstructorStub";
-  switch (argument_count()) {
-    case ANY:
-      os << "_Any";
-      break;
-    case NONE:
-      os << "_None";
-      break;
-    case ONE:
-      os << "_One";
-      break;
-    case MORE_THAN_ONE:
-      os << "_More_Than_One";
-      break;
-  }
-  return;
-}
-
-
 bool ToBooleanICStub::UpdateStatus(Handle<Object> object) {
   Types new_types = types();
   Types old_types = new_types;
@@ -2976,23 +2956,7 @@ void GrowArrayElementsStub::GenerateAssembly(
 }
 
 ArrayConstructorStub::ArrayConstructorStub(Isolate* isolate)
-    : PlatformCodeStub(isolate) {
-  minor_key_ = ArgumentCountBits::encode(ANY);
-}
-
-ArrayConstructorStub::ArrayConstructorStub(Isolate* isolate,
-                                           int argument_count)
-    : PlatformCodeStub(isolate) {
-  if (argument_count == 0) {
-    minor_key_ = ArgumentCountBits::encode(NONE);
-  } else if (argument_count == 1) {
-    minor_key_ = ArgumentCountBits::encode(ONE);
-  } else if (argument_count >= 2) {
-    minor_key_ = ArgumentCountBits::encode(MORE_THAN_ONE);
-  } else {
-    UNREACHABLE();
-  }
-}
+    : PlatformCodeStub(isolate) {}
 
 InternalArrayConstructorStub::InternalArrayConstructorStub(Isolate* isolate)
     : PlatformCodeStub(isolate) {}

src/code-stubs.h

@@ -1091,24 +1091,12 @@ enum AllocationSiteOverrideMode {
 
 class ArrayConstructorStub: public PlatformCodeStub {
  public:
-  enum ArgumentCountKey { ANY, NONE, ONE, MORE_THAN_ONE };
-
-  ArrayConstructorStub(Isolate* isolate, int argument_count);
-
   explicit ArrayConstructorStub(Isolate* isolate);
 
  private:
-  ArgumentCountKey argument_count() const {
-    return ArgumentCountBits::decode(minor_key_);
-  }
-
   void GenerateDispatchToArrayStub(MacroAssembler* masm,
                                    AllocationSiteOverrideMode mode);
 
-  void PrintName(std::ostream& os) const override;  // NOLINT
-
-  class ArgumentCountBits : public BitField<ArgumentCountKey, 0, 2> {};
-
   DEFINE_CALL_INTERFACE_DESCRIPTOR(ArrayNArgumentsConstructor);
   DEFINE_PLATFORM_CODE_STUB(ArrayConstructor, PlatformCodeStub);
 };

src/ia32/code-stubs-ia32.cc

@@ -1446,7 +1446,7 @@ void CallICStub::HandleArrayCase(MacroAssembler* masm, Label* miss) {
 
   __ mov(ebx, ecx);
   __ mov(edx, edi);
-  ArrayConstructorStub stub(masm->isolate(), arg_count());
+  ArrayConstructorStub stub(masm->isolate());
   __ TailCallStub(&stub);
 
   // Unreachable.
@@ -3830,36 +3830,22 @@ void CommonArrayConstructorStub::GenerateStubsAheadOfTime(Isolate* isolate) {
   }
 }
 
-
 void ArrayConstructorStub::GenerateDispatchToArrayStub(
-    MacroAssembler* masm,
-    AllocationSiteOverrideMode mode) {
-  if (argument_count() == ANY) {
-    Label not_zero_case, not_one_case;
-    __ test(eax, eax);
-    __ j(not_zero, &not_zero_case);
-    CreateArrayDispatch<ArrayNoArgumentConstructorStub>(masm, mode);
-
-    __ bind(&not_zero_case);
-    __ cmp(eax, 1);
-    __ j(greater, &not_one_case);
-    CreateArrayDispatchOneArgument(masm, mode);
-
-    __ bind(&not_one_case);
-    ArrayNArgumentsConstructorStub stub(masm->isolate());
-    __ TailCallStub(&stub);
-  } else if (argument_count() == NONE) {
-    CreateArrayDispatch<ArrayNoArgumentConstructorStub>(masm, mode);
-  } else if (argument_count() == ONE) {
-    CreateArrayDispatchOneArgument(masm, mode);
-  } else if (argument_count() == MORE_THAN_ONE) {
-    ArrayNArgumentsConstructorStub stub(masm->isolate());
-    __ TailCallStub(&stub);
-  } else {
-    UNREACHABLE();
-  }
-}
+    MacroAssembler* masm, AllocationSiteOverrideMode mode) {
+  Label not_zero_case, not_one_case;
+  __ test(eax, eax);
+  __ j(not_zero, &not_zero_case);
+  CreateArrayDispatch<ArrayNoArgumentConstructorStub>(masm, mode);
+
+  __ bind(&not_zero_case);
+  __ cmp(eax, 1);
+  __ j(greater, &not_one_case);
+  CreateArrayDispatchOneArgument(masm, mode);
 
+  __ bind(&not_one_case);
+  ArrayNArgumentsConstructorStub stub(masm->isolate());
+  __ TailCallStub(&stub);
+}
 
 void ArrayConstructorStub::Generate(MacroAssembler* masm) {
   // ----------- S t a t e -------------
@@ -3912,21 +3898,8 @@ void ArrayConstructorStub::Generate(MacroAssembler* masm) {
 
   // Subclassing.
   __ bind(&subclassing);
-  switch (argument_count()) {
-    case ANY:
-    case MORE_THAN_ONE:
-      __ mov(Operand(esp, eax, times_pointer_size, kPointerSize), edi);
-      __ add(eax, Immediate(3));
-      break;
-    case NONE:
-      __ mov(Operand(esp, 1 * kPointerSize), edi);
-      __ mov(eax, Immediate(3));
-      break;
-    case ONE:
-      __ mov(Operand(esp, 2 * kPointerSize), edi);
-      __ mov(eax, Immediate(4));
-      break;
-  }
+  __ mov(Operand(esp, eax, times_pointer_size, kPointerSize), edi);
+  __ add(eax, Immediate(3));
   __ PopReturnAddressTo(ecx);
   __ Push(edx);
   __ Push(ebx);

src/mips/code-stubs-mips.cc

@@ -1924,14 +1924,13 @@ void CallICStub::HandleArrayCase(MacroAssembler* masm, Label* miss) {
   __ LoadNativeContextSlot(Context::ARRAY_FUNCTION_INDEX, at);
   __ Branch(miss, ne, a1, Operand(at));
 
-  __ li(a0, Operand(arg_count()));
-
   // Increment the call count for monomorphic function calls.
   IncrementCallCount(masm, a2, a3);
 
   __ mov(a2, t0);
   __ mov(a3, a1);
-  ArrayConstructorStub stub(masm->isolate(), arg_count());
+  __ li(a0, Operand(arg_count()));
+  ArrayConstructorStub stub(masm->isolate());
   __ TailCallStub(&stub);
 }
 
@@ -3898,29 +3897,18 @@ void CommonArrayConstructorStub::GenerateStubsAheadOfTime(Isolate* isolate) {
 void ArrayConstructorStub::GenerateDispatchToArrayStub(
     MacroAssembler* masm,
     AllocationSiteOverrideMode mode) {
-  if (argument_count() == ANY) {
-    Label not_zero_case, not_one_case;
-    __ And(at, a0, a0);
-    __ Branch(&not_zero_case, ne, at, Operand(zero_reg));
-    CreateArrayDispatch<ArrayNoArgumentConstructorStub>(masm, mode);
-
-    __ bind(&not_zero_case);
-    __ Branch(&not_one_case, gt, a0, Operand(1));
-    CreateArrayDispatchOneArgument(masm, mode);
-
-    __ bind(&not_one_case);
-    ArrayNArgumentsConstructorStub stub(masm->isolate());
-    __ TailCallStub(&stub);
-  } else if (argument_count() == NONE) {
-    CreateArrayDispatch<ArrayNoArgumentConstructorStub>(masm, mode);
-  } else if (argument_count() == ONE) {
-    CreateArrayDispatchOneArgument(masm, mode);
-  } else if (argument_count() == MORE_THAN_ONE) {
-    ArrayNArgumentsConstructorStub stub(masm->isolate());
-    __ TailCallStub(&stub);
-  } else {
-    UNREACHABLE();
-  }
+  Label not_zero_case, not_one_case;
+  __ And(at, a0, a0);
+  __ Branch(&not_zero_case, ne, at, Operand(zero_reg));
+  CreateArrayDispatch<ArrayNoArgumentConstructorStub>(masm, mode);
+
+  __ bind(&not_zero_case);
+  __ Branch(&not_one_case, gt, a0, Operand(1));
+  CreateArrayDispatchOneArgument(masm, mode);
+
+  __ bind(&not_one_case);
+  ArrayNArgumentsConstructorStub stub(masm->isolate());
+  __ TailCallStub(&stub);
 }
 
 
@@ -3973,23 +3961,10 @@ void ArrayConstructorStub::Generate(MacroAssembler* masm) {
 
   // Subclassing.
   __ bind(&subclassing);
-  switch (argument_count()) {
-    case ANY:
-    case MORE_THAN_ONE:
-      __ Lsa(at, sp, a0, kPointerSizeLog2);
-      __ sw(a1, MemOperand(at));
-      __ li(at, Operand(3));
-      __ addu(a0, a0, at);
-      break;
-    case NONE:
-      __ sw(a1, MemOperand(sp, 0 * kPointerSize));
-      __ li(a0, Operand(3));
-      break;
-    case ONE:
-      __ sw(a1, MemOperand(sp, 1 * kPointerSize));
-      __ li(a0, Operand(4));
-      break;
-  }
+  __ Lsa(at, sp, a0, kPointerSizeLog2);
+  __ sw(a1, MemOperand(at));
+  __ li(at, Operand(3));
+  __ addu(a0, a0, at);
   __ Push(a3, a2);
   __ JumpToExternalReference(ExternalReference(Runtime::kNewArray, isolate()));
 }

src/mips64/code-stubs-mips64.cc

@@ -1971,14 +1971,13 @@ void CallICStub::HandleArrayCase(MacroAssembler* masm, Label* miss) {
   __ LoadNativeContextSlot(Context::ARRAY_FUNCTION_INDEX, at);
   __ Branch(miss, ne, a1, Operand(at));
 
-  __ li(a0, Operand(arg_count()));
-
   // Increment the call count for monomorphic function calls.
   IncrementCallCount(masm, a2, a3);
 
   __ mov(a2, a4);
   __ mov(a3, a1);
-  ArrayConstructorStub stub(masm->isolate(), arg_count());
+  __ li(a0, Operand(arg_count()));
+  ArrayConstructorStub stub(masm->isolate());
   __ TailCallStub(&stub);
 }
 
@@ -3903,29 +3902,18 @@ void CommonArrayConstructorStub::GenerateStubsAheadOfTime(Isolate* isolate) {
 void ArrayConstructorStub::GenerateDispatchToArrayStub(
     MacroAssembler* masm,
     AllocationSiteOverrideMode mode) {
-  if (argument_count() == ANY) {
-    Label not_zero_case, not_one_case;
-    __ And(at, a0, a0);
-    __ Branch(&not_zero_case, ne, at, Operand(zero_reg));
-    CreateArrayDispatch<ArrayNoArgumentConstructorStub>(masm, mode);
-
-    __ bind(&not_zero_case);
-    __ Branch(&not_one_case, gt, a0, Operand(1));
-    CreateArrayDispatchOneArgument(masm, mode);
-
-    __ bind(&not_one_case);
-    ArrayNArgumentsConstructorStub stub(masm->isolate());
-    __ TailCallStub(&stub);
-  } else if (argument_count() == NONE) {
-    CreateArrayDispatch<ArrayNoArgumentConstructorStub>(masm, mode);
-  } else if (argument_count() == ONE) {
-    CreateArrayDispatchOneArgument(masm, mode);
-  } else if (argument_count() == MORE_THAN_ONE) {
-    ArrayNArgumentsConstructorStub stub(masm->isolate());
-    __ TailCallStub(&stub);
-  } else {
-    UNREACHABLE();
-  }
+  Label not_zero_case, not_one_case;
+  __ And(at, a0, a0);
+  __ Branch(&not_zero_case, ne, at, Operand(zero_reg));
+  CreateArrayDispatch<ArrayNoArgumentConstructorStub>(masm, mode);
+
+  __ bind(&not_zero_case);
+  __ Branch(&not_one_case, gt, a0, Operand(1));
+  CreateArrayDispatchOneArgument(masm, mode);
+
+  __ bind(&not_one_case);
+  ArrayNArgumentsConstructorStub stub(masm->isolate());
+  __ TailCallStub(&stub);
 }
 
 
@@ -3978,23 +3966,10 @@ void ArrayConstructorStub::Generate(MacroAssembler* masm) {
 
   // Subclassing.
   __ bind(&subclassing);
-  switch (argument_count()) {
-    case ANY:
-    case MORE_THAN_ONE:
-      __ Dlsa(at, sp, a0, kPointerSizeLog2);
-      __ sd(a1, MemOperand(at));
-      __ li(at, Operand(3));
-      __ Daddu(a0, a0, at);
-      break;
-    case NONE:
-      __ sd(a1, MemOperand(sp, 0 * kPointerSize));
-      __ li(a0, Operand(3));
-      break;
-    case ONE:
-      __ sd(a1, MemOperand(sp, 1 * kPointerSize));
-      __ li(a0, Operand(4));
-      break;
-  }
+  __ Dlsa(at, sp, a0, kPointerSizeLog2);
+  __ sd(a1, MemOperand(at));
+  __ li(at, Operand(3));
+  __ Daddu(a0, a0, at);
   __ Push(a3, a2);
   __ JumpToExternalReference(ExternalReference(Runtime::kNewArray, isolate()));
 }

src/x64/code-stubs-x64.cc

@@ -1324,14 +1324,13 @@ void CallICStub::HandleArrayCase(MacroAssembler* masm, Label* miss) {
   __ cmpp(rdi, r8);
   __ j(not_equal, miss);
 
-  __ movp(rax, Immediate(arg_count()));
-
   // Increment the call count for monomorphic function calls.
   IncrementCallCount(masm, rbx, rdx);
 
   __ movp(rbx, rcx);
   __ movp(rdx, rdi);
-  ArrayConstructorStub stub(masm->isolate(), arg_count());
+  __ Set(rax, arg_count());
+  ArrayConstructorStub stub(masm->isolate());
   __ TailCallStub(&stub);
 }
 
@@ -3539,36 +3538,22 @@ void CommonArrayConstructorStub::GenerateStubsAheadOfTime(Isolate* isolate) {
   }
 }
 
-
 void ArrayConstructorStub::GenerateDispatchToArrayStub(
-    MacroAssembler* masm,
-    AllocationSiteOverrideMode mode) {
-  if (argument_count() == ANY) {
-    Label not_zero_case, not_one_case;
-    __ testp(rax, rax);
-    __ j(not_zero, &not_zero_case);
-    CreateArrayDispatch<ArrayNoArgumentConstructorStub>(masm, mode);
-
-    __ bind(&not_zero_case);
-    __ cmpl(rax, Immediate(1));
-    __ j(greater, &not_one_case);
-    CreateArrayDispatchOneArgument(masm, mode);
-
-    __ bind(&not_one_case);
-    ArrayNArgumentsConstructorStub stub(masm->isolate());
-    __ TailCallStub(&stub);
-  } else if (argument_count() == NONE) {
-    CreateArrayDispatch<ArrayNoArgumentConstructorStub>(masm, mode);
-  } else if (argument_count() == ONE) {
-    CreateArrayDispatchOneArgument(masm, mode);
-  } else if (argument_count() == MORE_THAN_ONE) {
-    ArrayNArgumentsConstructorStub stub(masm->isolate());
-    __ TailCallStub(&stub);
-  } else {
-    UNREACHABLE();
-  }
-}
+    MacroAssembler* masm, AllocationSiteOverrideMode mode) {
+  Label not_zero_case, not_one_case;
+  __ testp(rax, rax);
+  __ j(not_zero, &not_zero_case);
+  CreateArrayDispatch<ArrayNoArgumentConstructorStub>(masm, mode);
 
+  __ bind(&not_zero_case);
+  __ cmpl(rax, Immediate(1));
+  __ j(greater, &not_one_case);
+  CreateArrayDispatchOneArgument(masm, mode);
+
+  __ bind(&not_one_case);
+  ArrayNArgumentsConstructorStub stub(masm->isolate());
+  __ TailCallStub(&stub);
+}
 
 void ArrayConstructorStub::Generate(MacroAssembler* masm) {
   // ----------- S t a t e -------------
@@ -3621,27 +3606,9 @@ void ArrayConstructorStub::Generate(MacroAssembler* masm) {
 
   // Subclassing
   __ bind(&subclassing);
-  switch (argument_count()) {
-    case ANY:
-    case MORE_THAN_ONE: {
-      StackArgumentsAccessor args(rsp, rax);
-      __ movp(args.GetReceiverOperand(), rdi);
-      __ addp(rax, Immediate(3));
-      break;
-    }
-    case NONE: {
-      StackArgumentsAccessor args(rsp, 0);
-      __ movp(args.GetReceiverOperand(), rdi);
-      __ Set(rax, 3);
-      break;
-    }
-    case ONE: {
-      StackArgumentsAccessor args(rsp, 1);
-      __ movp(args.GetReceiverOperand(), rdi);
-      __ Set(rax, 4);
-      break;
-    }
-  }
+  StackArgumentsAccessor args(rsp, rax);
+  __ movp(args.GetReceiverOperand(), rdi);
+  __ addp(rax, Immediate(3));
   __ PopReturnAddressTo(rcx);
   __ Push(rdx);
   __ Push(rbx);