text: // 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_MIPS64
  
  #include "src/codegen.h"
  #include "src/debug/debug.h"
  #include "src/deoptimizer.h"
  #include "src/full-codegen/full-codegen.h"
  #include "src/runtime/runtime.h"
  
  namespace v8 {
  namespace internal {
  
  #define __ ACCESS_MASM(masm)
  
  void Builtins::Generate_Adaptor(MacroAssembler* masm, Address address,
                                  ExitFrameType exit_frame_type) {
    // ----------- S t a t e -------------
    //  -- a0                 : number of arguments excluding receiver
    //  -- a1                 : target
    //  -- a3                 : new.target
    //  -- sp[0]              : last argument
    //  -- ...
    //  -- sp[8 * (argc - 1)] : first argument
    //  -- sp[8 * agrc]       : receiver
    // -----------------------------------
    __ AssertFunction(a1);
  
    // Make sure we operate in the context of the called function (for example
    // ConstructStubs implemented in C++ will be run in the context of the caller
    // instead of the callee, due to the way that [[Construct]] is defined for
    // ordinary functions).
    __ ld(cp, FieldMemOperand(a1, JSFunction::kContextOffset));
  
    // JumpToExternalReference expects a0 to contain the number of arguments
    // including the receiver and the extra arguments.
    const int num_extra_args = 3;
    __ Daddu(a0, a0, num_extra_args + 1);
  
    // Insert extra arguments.
    __ SmiTag(a0);
    __ Push(a0, a1, a3);
    __ SmiUntag(a0);
  
    __ JumpToExternalReference(ExternalReference(address, masm->isolate()),
                               PROTECT, exit_frame_type == BUILTIN_EXIT);
  }
  
  // Load the built-in InternalArray function from the current context.
  static void GenerateLoadInternalArrayFunction(MacroAssembler* masm,
                                                Register result) {
    // Load the InternalArray function from the native context.
    __ LoadNativeContextSlot(Context::INTERNAL_ARRAY_FUNCTION_INDEX, result);
  }
  
  // Load the built-in Array function from the current context.
  static void GenerateLoadArrayFunction(MacroAssembler* masm, Register result) {
    // Load the Array function from the native context.
    __ LoadNativeContextSlot(Context::ARRAY_FUNCTION_INDEX, result);
  }
  
  void Builtins::Generate_InternalArrayCode(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- a0     : number of arguments
    //  -- ra     : return address
    //  -- sp[...]: constructor arguments
    // -----------------------------------
    Label generic_array_code, one_or_more_arguments, two_or_more_arguments;
  
    // Get the InternalArray function.
    GenerateLoadInternalArrayFunction(masm, a1);
  
    if (FLAG_debug_code) {
      // Initial map for the builtin InternalArray functions should be maps.
      __ ld(a2, FieldMemOperand(a1, JSFunction::kPrototypeOrInitialMapOffset));
      __ SmiTst(a2, a4);
      __ Assert(ne, kUnexpectedInitialMapForInternalArrayFunction, a4,
                Operand(zero_reg));
      __ GetObjectType(a2, a3, a4);
      __ Assert(eq, kUnexpectedInitialMapForInternalArrayFunction, a4,
                Operand(MAP_TYPE));
    }
  
    // Run the native code for the InternalArray function called as a normal
    // function.
    // Tail call a stub.
    InternalArrayConstructorStub stub(masm->isolate());
    __ TailCallStub(&stub);
  }
  
  void Builtins::Generate_ArrayCode(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- a0     : number of arguments
    //  -- ra     : return address
    //  -- sp[...]: constructor arguments
    // -----------------------------------
    Label generic_array_code;
  
    // Get the Array function.
    GenerateLoadArrayFunction(masm, a1);
  
    if (FLAG_debug_code) {
      // Initial map for the builtin Array functions should be maps.
      __ ld(a2, FieldMemOperand(a1, JSFunction::kPrototypeOrInitialMapOffset));
      __ SmiTst(a2, a4);
      __ Assert(ne, kUnexpectedInitialMapForArrayFunction1, a4,
                Operand(zero_reg));
      __ GetObjectType(a2, a3, a4);
      __ Assert(eq, kUnexpectedInitialMapForArrayFunction2, a4,
                Operand(MAP_TYPE));
    }
  
    // Run the native code for the Array function called as a normal function.
    // Tail call a stub.
    __ mov(a3, a1);
    __ LoadRoot(a2, Heap::kUndefinedValueRootIndex);
    ArrayConstructorStub stub(masm->isolate());
    __ TailCallStub(&stub);
  }
  
  // static
  void Builtins::Generate_MathMaxMin(MacroAssembler* masm, MathMaxMinKind kind) {
    // ----------- S t a t e -------------
    //  -- a0                     : number of arguments
    //  -- a1                     : function
    //  -- cp                     : context
    //  -- ra                     : return address
    //  -- sp[(argc - n - 1) * 8] : arg[n] (zero-based)
    //  -- sp[argc * 8]           : receiver
    // -----------------------------------
    Heap::RootListIndex const root_index =
        (kind == MathMaxMinKind::kMin) ? Heap::kInfinityValueRootIndex
                                       : Heap::kMinusInfinityValueRootIndex;
  
    // Load the accumulator with the default return value (either -Infinity or
    // +Infinity), with the tagged value in t1 and the double value in f0.
    __ LoadRoot(t1, root_index);
    __ ldc1(f0, FieldMemOperand(t1, HeapNumber::kValueOffset));
  
    Label done_loop, loop, done;
    __ mov(a3, a0);
    __ bind(&loop);
    {
      // Check if all parameters done.
      __ Dsubu(a3, a3, Operand(1));
      __ Branch(&done_loop, lt, a3, Operand(zero_reg));
  
      // Load the next parameter tagged value into a2.
      __ Dlsa(at, sp, a3, kPointerSizeLog2);
      __ ld(a2, MemOperand(at));
  
      // Load the double value of the parameter into f2, maybe converting the
      // parameter to a number first using the ToNumber builtin if necessary.
      Label convert, convert_smi, convert_number, done_convert;
      __ bind(&convert);
      __ JumpIfSmi(a2, &convert_smi);
      __ ld(a4, FieldMemOperand(a2, HeapObject::kMapOffset));
      __ JumpIfRoot(a4, Heap::kHeapNumberMapRootIndex, &convert_number);
      {
        // Parameter is not a Number, use the ToNumber builtin to convert it.
        FrameScope scope(masm, StackFrame::MANUAL);
        __ SmiTag(a0);
        __ SmiTag(a3);
        __ EnterBuiltinFrame(cp, a1, a0);
        __ Push(t1, a3);
        __ mov(a0, a2);
        __ Call(masm->isolate()->builtins()->ToNumber(), RelocInfo::CODE_TARGET);
        __ mov(a2, v0);
        __ Pop(t1, a3);
        __ LeaveBuiltinFrame(cp, a1, a0);
        __ SmiUntag(a3);
        __ SmiUntag(a0);
        {
          // Restore the double accumulator value (f0).
          Label restore_smi, done_restore;
          __ JumpIfSmi(t1, &restore_smi);
          __ ldc1(f0, FieldMemOperand(t1, HeapNumber::kValueOffset));
          __ jmp(&done_restore);
          __ bind(&restore_smi);
          __ SmiToDoubleFPURegister(t1, f0, a4);
          __ bind(&done_restore);
        }
      }
      __ jmp(&convert);
      __ bind(&convert_number);
      __ ldc1(f2, FieldMemOperand(a2, HeapNumber::kValueOffset));
      __ jmp(&done_convert);
      __ bind(&convert_smi);
      __ SmiToDoubleFPURegister(a2, f2, a4);
      __ bind(&done_convert);
  
      // Perform the actual comparison with using Min/Max macro instructions the
      // accumulator value on the left hand side (f0) and the next parameter value
      // on the right hand side (f2).
      // We need to work out which HeapNumber (or smi) the result came from.
      Label compare_nan, ool_min, ool_max;
      __ BranchF(nullptr, &compare_nan, eq, f0, f2);
      __ Move(a4, f0);
      if (kind == MathMaxMinKind::kMin) {
        __ Float64Min(f0, f0, f2, &ool_min);
      } else {
        DCHECK(kind == MathMaxMinKind::kMax);
        __ Float64Max(f0, f0, f2, &ool_max);
      }
      __ jmp(&done);
  
      __ bind(&ool_min);
      __ Float64MinOutOfLine(f0, f0, f2);
      __ jmp(&done);
  
      __ bind(&ool_max);
      __ Float64MaxOutOfLine(f0, f0, f2);
  
      __ bind(&done);
      __ Move(at, f0);
      __ Branch(&loop, eq, a4, Operand(at));
      __ mov(t1, a2);
      __ jmp(&loop);
  
      // At least one side is NaN, which means that the result will be NaN too.
      __ bind(&compare_nan);
      __ LoadRoot(t1, Heap::kNanValueRootIndex);
      __ ldc1(f0, FieldMemOperand(t1, HeapNumber::kValueOffset));
      __ jmp(&loop);
    }
  
    __ bind(&done_loop);
    // Drop all slots, including the receiver.
    __ Daddu(a0, a0, Operand(1));
    __ Dlsa(sp, sp, a0, kPointerSizeLog2);
    __ Ret(USE_DELAY_SLOT);
    __ mov(v0, t1);  // In delay slot.
  }
  
  // static
  void Builtins::Generate_NumberConstructor(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- a0                     : number of arguments
    //  -- a1                     : constructor function
    //  -- cp                     : context
    //  -- ra                     : return address
    //  -- sp[(argc - n - 1) * 8] : arg[n] (zero based)
    //  -- sp[argc * 8]           : receiver
    // -----------------------------------
  
    // 1. Load the first argument into a0 and get rid of the rest (including the
    // receiver).
    Label no_arguments;
    {
      __ Branch(USE_DELAY_SLOT, &no_arguments, eq, a0, Operand(zero_reg));
      __ Dsubu(t1, a0, Operand(1));  // In delay slot.
      __ mov(t0, a0);                // Store argc in t0.
      __ Dlsa(at, sp, t1, kPointerSizeLog2);
      __ ld(a0, MemOperand(at));
    }
  
    // 2a. Convert first argument to number.
    {
      FrameScope scope(masm, StackFrame::MANUAL);
      __ SmiTag(t0);
      __ EnterBuiltinFrame(cp, a1, t0);
      __ Call(masm->isolate()->builtins()->ToNumber(), RelocInfo::CODE_TARGET);
      __ LeaveBuiltinFrame(cp, a1, t0);
      __ SmiUntag(t0);
    }
  
    {
      // Drop all arguments including the receiver.
      __ Dlsa(sp, sp, t0, kPointerSizeLog2);
      __ DropAndRet(1);
    }
  
    // 2b. No arguments, return +0.
    __ bind(&no_arguments);
    __ Move(v0, Smi::kZero);
    __ DropAndRet(1);
  }
  
  void Builtins::Generate_NumberConstructor_ConstructStub(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- a0                     : number of arguments
    //  -- a1                     : constructor function
    //  -- a3                     : new target
    //  -- cp                     : context
    //  -- ra                     : return address
    //  -- sp[(argc - n - 1) * 8] : arg[n] (zero based)
    //  -- sp[argc * 8]           : receiver
    // -----------------------------------
  
    // 1. Make sure we operate in the context of the called function.
    __ ld(cp, FieldMemOperand(a1, JSFunction::kContextOffset));
  
    // 2. Load the first argument into a0 and get rid of the rest (including the
    // receiver).
    {
      Label no_arguments, done;
      __ mov(t0, a0);  // Store argc in t0.
      __ Branch(USE_DELAY_SLOT, &no_arguments, eq, a0, Operand(zero_reg));
      __ Dsubu(a0, a0, Operand(1));  // In delay slot.
      __ Dlsa(at, sp, a0, kPointerSizeLog2);
      __ ld(a0, MemOperand(at));
      __ jmp(&done);
      __ bind(&no_arguments);
      __ Move(a0, Smi::kZero);
      __ bind(&done);
    }
  
    // 3. Make sure a0 is a number.
    {
      Label done_convert;
      __ JumpIfSmi(a0, &done_convert);
      __ GetObjectType(a0, a2, a2);
      __ Branch(&done_convert, eq, a2, Operand(HEAP_NUMBER_TYPE));
      {
        FrameScope scope(masm, StackFrame::MANUAL);
        __ SmiTag(t0);
        __ EnterBuiltinFrame(cp, a1, t0);
        __ Push(a3);
        __ Call(masm->isolate()->builtins()->ToNumber(), RelocInfo::CODE_TARGET);
        __ Move(a0, v0);
        __ Pop(a3);
        __ LeaveBuiltinFrame(cp, a1, t0);
        __ SmiUntag(t0);
      }
      __ bind(&done_convert);
    }
  
    // 4. Check if new target and constructor differ.
    Label drop_frame_and_ret, new_object;
    __ Branch(&new_object, ne, a1, Operand(a3));
  
    // 5. Allocate a JSValue wrapper for the number.
    __ AllocateJSValue(v0, a1, a0, a2, t1, &new_object);
    __ jmp(&drop_frame_and_ret);
  
    // 6. Fallback to the runtime to create new object.
    __ bind(&new_object);
    {
      FrameScope scope(masm, StackFrame::MANUAL);
      FastNewObjectStub stub(masm->isolate());
      __ SmiTag(t0);
      __ EnterBuiltinFrame(cp, a1, t0);
      __ Push(a0);
      __ CallStub(&stub);
      __ Pop(a0);
      __ LeaveBuiltinFrame(cp, a1, t0);
      __ SmiUntag(t0);
    }
    __ sd(a0, FieldMemOperand(v0, JSValue::kValueOffset));
  
    __ bind(&drop_frame_and_ret);
    {
      __ Dlsa(sp, sp, t0, kPointerSizeLog2);
      __ DropAndRet(1);
    }
  }
  
  // static
  void Builtins::Generate_StringConstructor(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- a0                     : number of arguments
    //  -- a1                     : constructor function
    //  -- cp                     : context
    //  -- ra                     : return address
    //  -- sp[(argc - n - 1) * 8] : arg[n] (zero based)
    //  -- sp[argc * 8]           : receiver
    // -----------------------------------
  
    // 1. Load the first argument into a0 and get rid of the rest (including the
    // receiver).
    Label no_arguments;
    {
      __ Branch(USE_DELAY_SLOT, &no_arguments, eq, a0, Operand(zero_reg));
      __ Dsubu(t1, a0, Operand(1));  // In delay slot.
      __ mov(t0, a0);                // Store argc in t0.
      __ Dlsa(at, sp, t1, kPointerSizeLog2);
      __ ld(a0, MemOperand(at));
    }
  
    // 2a. At least one argument, return a0 if it's a string, otherwise
    // dispatch to appropriate conversion.
    Label drop_frame_and_ret, to_string, symbol_descriptive_string;
    {
      __ JumpIfSmi(a0, &to_string);
      __ GetObjectType(a0, t1, t1);
      STATIC_ASSERT(FIRST_NONSTRING_TYPE == SYMBOL_TYPE);
      __ Subu(t1, t1, Operand(FIRST_NONSTRING_TYPE));
      __ Branch(&symbol_descriptive_string, eq, t1, Operand(zero_reg));
      __ Branch(&to_string, gt, t1, Operand(zero_reg));
      __ mov(v0, a0);
      __ jmp(&drop_frame_and_ret);
    }
  
    // 2b. No arguments, return the empty string (and pop the receiver).
    __ bind(&no_arguments);
    {
      __ LoadRoot(v0, Heap::kempty_stringRootIndex);
      __ DropAndRet(1);
    }
  
    // 3a. Convert a0 to a string.
    __ bind(&to_string);
    {
      FrameScope scope(masm, StackFrame::MANUAL);
      __ SmiTag(t0);
      __ EnterBuiltinFrame(cp, a1, t0);
      __ Call(masm->isolate()->builtins()->ToString(), RelocInfo::CODE_TARGET);
      __ LeaveBuiltinFrame(cp, a1, t0);
      __ SmiUntag(t0);
    }
    __ jmp(&drop_frame_and_ret);
  
    // 3b. Convert symbol in a0 to a string.
    __ bind(&symbol_descriptive_string);
    {
      __ Dlsa(sp, sp, t0, kPointerSizeLog2);
      __ Drop(1);
      __ Push(a0);
      __ TailCallRuntime(Runtime::kSymbolDescriptiveString);
    }
  
    __ bind(&drop_frame_and_ret);
    {
      __ Dlsa(sp, sp, t0, kPointerSizeLog2);
      __ DropAndRet(1);
    }
  }
  
  void Builtins::Generate_StringConstructor_ConstructStub(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- a0                     : number of arguments
    //  -- a1                     : constructor function
    //  -- a3                     : new target
    //  -- cp                     : context
    //  -- ra                     : return address
    //  -- sp[(argc - n - 1) * 8] : arg[n] (zero based)
    //  -- sp[argc * 8]           : receiver
    // -----------------------------------
  
    // 1. Make sure we operate in the context of the called function.
    __ ld(cp, FieldMemOperand(a1, JSFunction::kContextOffset));
  
    // 2. Load the first argument into a0 and get rid of the rest (including the
    // receiver).
    {
      Label no_arguments, done;
      __ mov(t0, a0);  // Store argc in t0.
      __ Branch(USE_DELAY_SLOT, &no_arguments, eq, a0, Operand(zero_reg));
      __ Dsubu(a0, a0, Operand(1));
      __ Dlsa(at, sp, a0, kPointerSizeLog2);
      __ ld(a0, MemOperand(at));
      __ jmp(&done);
      __ bind(&no_arguments);
      __ LoadRoot(a0, Heap::kempty_stringRootIndex);
      __ bind(&done);
    }
  
    // 3. Make sure a0 is a string.
    {
      Label convert, done_convert;
      __ JumpIfSmi(a0, &convert);
      __ GetObjectType(a0, a2, a2);
      __ And(t1, a2, Operand(kIsNotStringMask));
      __ Branch(&done_convert, eq, t1, Operand(zero_reg));
      __ bind(&convert);
      {
        FrameScope scope(masm, StackFrame::MANUAL);
        __ SmiTag(t0);
        __ EnterBuiltinFrame(cp, a1, t0);
        __ Push(a3);
        __ Call(masm->isolate()->builtins()->ToString(), RelocInfo::CODE_TARGET);
        __ Move(a0, v0);
        __ Pop(a3);
        __ LeaveBuiltinFrame(cp, a1, t0);
        __ SmiUntag(t0);
      }
      __ bind(&done_convert);
    }
  
    // 4. Check if new target and constructor differ.
    Label drop_frame_and_ret, new_object;
    __ Branch(&new_object, ne, a1, Operand(a3));
  
    // 5. Allocate a JSValue wrapper for the string.
    __ AllocateJSValue(v0, a1, a0, a2, t1, &new_object);
    __ jmp(&drop_frame_and_ret);
  
    // 6. Fallback to the runtime to create new object.
    __ bind(&new_object);
    {
      FrameScope scope(masm, StackFrame::MANUAL);
      FastNewObjectStub stub(masm->isolate());
      __ SmiTag(t0);
      __ EnterBuiltinFrame(cp, a1, t0);
      __ Push(a0);
      __ CallStub(&stub);
      __ Pop(a0);
      __ LeaveBuiltinFrame(cp, a1, t0);
      __ SmiUntag(t0);
    }
    __ sd(a0, FieldMemOperand(v0, JSValue::kValueOffset));
  
    __ bind(&drop_frame_and_ret);
    {
      __ Dlsa(sp, sp, t0, kPointerSizeLog2);
      __ DropAndRet(1);
    }
  }
  
  static void GenerateTailCallToSharedCode(MacroAssembler* masm) {
    __ ld(a2, FieldMemOperand(a1, JSFunction::kSharedFunctionInfoOffset));
    __ ld(a2, FieldMemOperand(a2, SharedFunctionInfo::kCodeOffset));
    __ Daddu(at, a2, Operand(Code::kHeaderSize - kHeapObjectTag));
    __ Jump(at);
  }
  
  static void GenerateTailCallToReturnedCode(MacroAssembler* masm,
                                             Runtime::FunctionId function_id) {
    // ----------- S t a t e -------------
    //  -- a0 : argument count (preserved for callee)
    //  -- a1 : target function (preserved for callee)
    //  -- a3 : new target (preserved for callee)
    // -----------------------------------
    {
      FrameScope scope(masm, StackFrame::INTERNAL);
      // Push a copy of the function onto the stack.
      // Push a copy of the target function and the new target.
      __ SmiTag(a0);
      __ Push(a0, a1, a3, a1);
  
      __ CallRuntime(function_id, 1);
      // Restore target function and new target.
      __ Pop(a0, a1, a3);
      __ SmiUntag(a0);
    }
  
    __ Daddu(at, v0, Operand(Code::kHeaderSize - kHeapObjectTag));
    __ Jump(at);
  }
  
  void Builtins::Generate_InOptimizationQueue(MacroAssembler* masm) {
    // Checking whether the queued function is ready for install is optional,
    // since we come across interrupts and stack checks elsewhere.  However,
    // not checking may delay installing ready functions, and always checking
    // would be quite expensive.  A good compromise is to first check against
    // stack limit as a cue for an interrupt signal.
    Label ok;
    __ LoadRoot(a4, Heap::kStackLimitRootIndex);
    __ Branch(&ok, hs, sp, Operand(a4));
  
    GenerateTailCallToReturnedCode(masm, Runtime::kTryInstallOptimizedCode);
  
    __ bind(&ok);
    GenerateTailCallToSharedCode(masm);
  }
  
  namespace {
  
  void Generate_JSConstructStubHelper(MacroAssembler* masm, bool is_api_function,
                                      bool create_implicit_receiver,
                                      bool check_derived_construct) {
    // ----------- S t a t e -------------
    //  -- a0     : number of arguments
    //  -- a1     : constructor function
    //  -- a3     : new target
    //  -- cp     : context
    //  -- ra     : return address
    //  -- sp[...]: constructor arguments
    // -----------------------------------
  
    Isolate* isolate = masm->isolate();
  
    // Enter a construct frame.
    {
      FrameScope scope(masm, StackFrame::CONSTRUCT);
  
      // Preserve the incoming parameters on the stack.
      __ SmiTag(a0);
      __ Push(cp, a0);
  
      if (create_implicit_receiver) {
        __ Push(a1, a3);
        FastNewObjectStub stub(masm->isolate());
        __ CallStub(&stub);
        __ mov(t0, v0);
        __ Pop(a1, a3);
  
        // ----------- S t a t e -------------
        // -- a1: constructor function
        // -- a3: new target
        // -- t0: newly allocated object
        // -----------------------------------
        __ ld(a0, MemOperand(sp));
      }
      __ SmiUntag(a0);
  
      if (create_implicit_receiver) {
        // Push the allocated receiver to the stack. We need two copies
        // because we may have to return the original one and the calling
        // conventions dictate that the called function pops the receiver.
        __ Push(t0, t0);
      } else {
        __ PushRoot(Heap::kTheHoleValueRootIndex);
      }
  
      // Set up pointer to last argument.
      __ Daddu(a2, fp, Operand(StandardFrameConstants::kCallerSPOffset));
  
      // Copy arguments and receiver to the expression stack.
      // a0: number of arguments
      // a1: constructor function
      // a2: address of last argument (caller sp)
      // a3: new target
      // t0: number of arguments (smi-tagged)
      // sp[0]: receiver
      // sp[1]: receiver
      // sp[2]: number of arguments (smi-tagged)
      Label loop, entry;
      __ mov(t0, a0);
      __ jmp(&entry);
      __ bind(&loop);
      __ Dlsa(a4, a2, t0, kPointerSizeLog2);
      __ ld(a5, MemOperand(a4));
      __ push(a5);
      __ bind(&entry);
      __ Daddu(t0, t0, Operand(-1));
      __ Branch(&loop, greater_equal, t0, Operand(zero_reg));
  
      // Call the function.
      // a0: number of arguments
      // a1: constructor function
      // a3: new target
      ParameterCount actual(a0);
      __ InvokeFunction(a1, a3, actual, CALL_FUNCTION,
                        CheckDebugStepCallWrapper());
  
      // Store offset of return address for deoptimizer.
      if (create_implicit_receiver && !is_api_function) {
        masm->isolate()->heap()->SetConstructStubDeoptPCOffset(masm->pc_offset());
      }
  
      // Restore context from the frame.
      __ ld(cp, MemOperand(fp, ConstructFrameConstants::kContextOffset));
  
      if (create_implicit_receiver) {
        // If the result is an object (in the ECMA sense), we should get rid
        // of the receiver and use the result; see ECMA-262 section 13.2.2-7
        // on page 74.
        Label use_receiver, exit;
  
        // If the result is a smi, it is *not* an object in the ECMA sense.
        // v0: result
        // sp[0]: receiver (newly allocated object)
        // sp[1]: number of arguments (smi-tagged)
        __ JumpIfSmi(v0, &use_receiver);
  
        // If the type of the result (stored in its map) is less than
        // FIRST_JS_RECEIVER_TYPE, it is not an object in the ECMA sense.
        __ GetObjectType(v0, a1, a3);
        __ Branch(&exit, greater_equal, a3, Operand(FIRST_JS_RECEIVER_TYPE));
  
        // Throw away the result of the constructor invocation and use the
        // on-stack receiver as the result.
        __ bind(&use_receiver);
        __ ld(v0, MemOperand(sp));
  
        // Remove receiver from the stack, remove caller arguments, and
        // return.
        __ bind(&exit);
        // v0: result
        // sp[0]: receiver (newly allocated object)
        // sp[1]: number of arguments (smi-tagged)
        __ ld(a1, MemOperand(sp, 1 * kPointerSize));
      } else {
        __ ld(a1, MemOperand(sp));
      }
  
      // Leave construct frame.
    }
  
    // ES6 9.2.2. Step 13+
    // Check that the result is not a Smi, indicating that the constructor result
    // from a derived class is neither undefined nor an Object.
    if (check_derived_construct) {
      Label dont_throw;
      __ JumpIfNotSmi(v0, &dont_throw);
      {
        FrameScope scope(masm, StackFrame::INTERNAL);
        __ CallRuntime(Runtime::kThrowDerivedConstructorReturnedNonObject);
      }
      __ bind(&dont_throw);
    }
  
    __ SmiScale(a4, a1, kPointerSizeLog2);
    __ Daddu(sp, sp, a4);
    __ Daddu(sp, sp, kPointerSize);
    if (create_implicit_receiver) {
      __ IncrementCounter(isolate->counters()->constructed_objects(), 1, a1, a2);
    }
    __ Ret();
  }
  
  }  // namespace
  
  void Builtins::Generate_JSConstructStubGeneric(MacroAssembler* masm) {
    Generate_JSConstructStubHelper(masm, false, true, false);
  }
  
  void Builtins::Generate_JSConstructStubApi(MacroAssembler* masm) {
    Generate_JSConstructStubHelper(masm, true, false, false);
  }
  
  void Builtins::Generate_JSBuiltinsConstructStub(MacroAssembler* masm) {
    Generate_JSConstructStubHelper(masm, false, false, false);
  }
  
  void Builtins::Generate_JSBuiltinsConstructStubForDerived(
      MacroAssembler* masm) {
    Generate_JSConstructStubHelper(masm, false, false, true);
  }
  
  // static
  void Builtins::Generate_ResumeGeneratorTrampoline(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- v0 : the value to pass to the generator
    //  -- a1 : the JSGeneratorObject to resume
    //  -- a2 : the resume mode (tagged)
    //  -- ra : return address
    // -----------------------------------
    __ AssertGeneratorObject(a1);
  
    // Store input value into generator object.
    __ sd(v0, FieldMemOperand(a1, JSGeneratorObject::kInputOrDebugPosOffset));
    __ RecordWriteField(a1, JSGeneratorObject::kInputOrDebugPosOffset, v0, a3,
                        kRAHasNotBeenSaved, kDontSaveFPRegs);
  
    // Store resume mode into generator object.
    __ sd(a2, FieldMemOperand(a1, JSGeneratorObject::kResumeModeOffset));
  
    // Load suspended function and context.
    __ ld(cp, FieldMemOperand(a1, JSGeneratorObject::kContextOffset));
    __ ld(a4, FieldMemOperand(a1, JSGeneratorObject::kFunctionOffset));
  
    // Flood function if we are stepping.
    Label prepare_step_in_if_stepping, prepare_step_in_suspended_generator;
    Label stepping_prepared;
    ExternalReference last_step_action =
        ExternalReference::debug_last_step_action_address(masm->isolate());
    STATIC_ASSERT(StepFrame > StepIn);
    __ li(a5, Operand(last_step_action));
    __ lb(a5, MemOperand(a5));
    __ Branch(&prepare_step_in_if_stepping, ge, a5, Operand(StepIn));
  
    // Flood function if we need to continue stepping in the suspended generator.
    ExternalReference debug_suspended_generator =
        ExternalReference::debug_suspended_generator_address(masm->isolate());
    __ li(a5, Operand(debug_suspended_generator));
    __ ld(a5, MemOperand(a5));
    __ Branch(&prepare_step_in_suspended_generator, eq, a1, Operand(a5));
    __ bind(&stepping_prepared);
  
    // Push receiver.
    __ ld(a5, FieldMemOperand(a1, JSGeneratorObject::kReceiverOffset));
    __ Push(a5);
  
    // ----------- S t a t e -------------
    //  -- a1    : the JSGeneratorObject to resume
    //  -- a2    : the resume mode (tagged)
    //  -- a4    : generator function
    //  -- cp    : generator context
    //  -- ra    : return address
    //  -- sp[0] : generator receiver
    // -----------------------------------
  
    // Push holes for arguments to generator function. Since the parser forced
    // context allocation for any variables in generators, the actual argument
    // values have already been copied into the context and these dummy values
    // will never be used.
    __ ld(a3, FieldMemOperand(a4, JSFunction::kSharedFunctionInfoOffset));
    __ lw(a3,
          FieldMemOperand(a3, SharedFunctionInfo::kFormalParameterCountOffset));
    {
      Label done_loop, loop;
      __ bind(&loop);
      __ Dsubu(a3, a3, Operand(1));
      __ Branch(&done_loop, lt, a3, Operand(zero_reg));
      __ PushRoot(Heap::kTheHoleValueRootIndex);
      __ Branch(&loop);
      __ bind(&done_loop);
    }
  
    // Underlying function needs to have bytecode available.
    if (FLAG_debug_code) {
      __ ld(a3, FieldMemOperand(a4, JSFunction::kSharedFunctionInfoOffset));
      __ ld(a3, FieldMemOperand(a3, SharedFunctionInfo::kFunctionDataOffset));
      __ GetObjectType(a3, a3, a3);
      __ Assert(eq, kMissingBytecodeArray, a3, Operand(BYTECODE_ARRAY_TYPE));
    }
  
    // Resume (Ignition/TurboFan) generator object.
    {
      __ ld(a0, FieldMemOperand(a4, JSFunction::kSharedFunctionInfoOffset));
      __ lw(a0,
            FieldMemOperand(a0, SharedFunctionInfo::kFormalParameterCountOffset));
      // We abuse new.target both to indicate that this is a resume call and to
      // pass in the generator object.  In ordinary calls, new.target is always
      // undefined because generator functions are non-constructable.
      __ Move(a3, a1);
      __ Move(a1, a4);
      __ ld(a2, FieldMemOperand(a1, JSFunction::kCodeEntryOffset));
      __ Jump(a2);
    }
  
    __ bind(&prepare_step_in_if_stepping);
    {
      FrameScope scope(masm, StackFrame::INTERNAL);
      __ Push(a1, a2, a4);
      __ CallRuntime(Runtime::kDebugPrepareStepInIfStepping);
      __ Pop(a1, a2);
    }
    __ Branch(USE_DELAY_SLOT, &stepping_prepared);
    __ ld(a4, FieldMemOperand(a1, JSGeneratorObject::kFunctionOffset));
  
    __ bind(&prepare_step_in_suspended_generator);
    {
      FrameScope scope(masm, StackFrame::INTERNAL);
      __ Push(a1, a2);
      __ CallRuntime(Runtime::kDebugPrepareStepInSuspendedGenerator);
      __ Pop(a1, a2);
    }
    __ Branch(USE_DELAY_SLOT, &stepping_prepared);
    __ ld(a4, FieldMemOperand(a1, JSGeneratorObject::kFunctionOffset));
  }
  
  void Builtins::Generate_ConstructedNonConstructable(MacroAssembler* masm) {
    FrameScope scope(masm, StackFrame::INTERNAL);
    __ Push(a1);
    __ CallRuntime(Runtime::kThrowConstructedNonConstructable);
  }
  
  enum IsTagged { kArgcIsSmiTagged, kArgcIsUntaggedInt };
  
  // Clobbers a2; preserves all other registers.
  static void Generate_CheckStackOverflow(MacroAssembler* masm, Register argc,
                                          IsTagged argc_is_tagged) {
    // Check the stack for overflow. We are not trying to catch
    // interruptions (e.g. debug break and preemption) here, so the "real stack
    // limit" is checked.
    Label okay;
    __ LoadRoot(a2, Heap::kRealStackLimitRootIndex);
    // Make a2 the space we have left. The stack might already be overflowed
    // here which will cause r2 to become negative.
    __ dsubu(a2, sp, a2);
    // Check if the arguments will overflow the stack.
    if (argc_is_tagged == kArgcIsSmiTagged) {
      __ SmiScale(a7, v0, kPointerSizeLog2);
    } else {
      DCHECK(argc_is_tagged == kArgcIsUntaggedInt);
      __ dsll(a7, argc, kPointerSizeLog2);
    }
    __ Branch(&okay, gt, a2, Operand(a7));  // Signed comparison.
  
    // Out of stack space.
    __ CallRuntime(Runtime::kThrowStackOverflow);
  
    __ bind(&okay);
  }
  
  static void Generate_JSEntryTrampolineHelper(MacroAssembler* masm,
                                               bool is_construct) {
    // Called from JSEntryStub::GenerateBody
  
    // ----------- S t a t e -------------
    //  -- a0: new.target
    //  -- a1: function
    //  -- a2: receiver_pointer
    //  -- a3: argc
    //  -- s0: argv
    // -----------------------------------
    ProfileEntryHookStub::MaybeCallEntryHook(masm);
  
    // Enter an internal frame.
    {
      FrameScope scope(masm, StackFrame::INTERNAL);
  
      // Setup the context (we need to use the caller context from the isolate).
      ExternalReference context_address(Isolate::kContextAddress,
                                        masm->isolate());
      __ li(cp, Operand(context_address));
      __ ld(cp, MemOperand(cp));
  
      // Push the function and the receiver onto the stack.
      __ Push(a1, a2);
  
      // Check if we have enough stack space to push all arguments.
      // Clobbers a2.
      Generate_CheckStackOverflow(masm, a3, kArgcIsUntaggedInt);
  
      // Remember new.target.
      __ mov(a5, a0);
  
      // Copy arguments to the stack in a loop.
      // a3: argc
      // s0: argv, i.e. points to first arg
      Label loop, entry;
      __ Dlsa(a6, s0, a3, kPointerSizeLog2);
      __ b(&entry);
      __ nop();  // Branch delay slot nop.
      // a6 points past last arg.
      __ bind(&loop);
      __ ld(a4, MemOperand(s0));  // Read next parameter.
      __ daddiu(s0, s0, kPointerSize);
      __ ld(a4, MemOperand(a4));  // Dereference handle.
      __ push(a4);                // Push parameter.
      __ bind(&entry);
      __ Branch(&loop, ne, s0, Operand(a6));
  
      // Setup new.target and argc.
      __ mov(a0, a3);
      __ mov(a3, a5);
  
      // Initialize all JavaScript callee-saved registers, since they will be seen
      // by the garbage collector as part of handlers.
      __ LoadRoot(a4, Heap::kUndefinedValueRootIndex);
      __ mov(s1, a4);
      __ mov(s2, a4);
      __ mov(s3, a4);
      __ mov(s4, a4);
      __ mov(s5, a4);
      // s6 holds the root address. Do not clobber.
      // s7 is cp. Do not init.
  
      // Invoke the code.
      Handle<Code> builtin = is_construct
                                 ? masm->isolate()->builtins()->Construct()
                                 : masm->isolate()->builtins()->Call();
      __ Call(builtin, RelocInfo::CODE_TARGET);
  
      // Leave internal frame.
    }
    __ Jump(ra);
  }
  
  void Builtins::Generate_JSEntryTrampoline(MacroAssembler* masm) {
    Generate_JSEntryTrampolineHelper(masm, false);
  }
  
  void Builtins::Generate_JSConstructEntryTrampoline(MacroAssembler* masm) {
    Generate_JSEntryTrampolineHelper(masm, true);
  }
  
  static void LeaveInterpreterFrame(MacroAssembler* masm, Register scratch) {
    Register args_count = scratch;
  
    // Get the arguments + receiver count.
    __ ld(args_count,
          MemOperand(fp, InterpreterFrameConstants::kBytecodeArrayFromFp));
    __ lw(t0, FieldMemOperand(args_count, BytecodeArray::kParameterSizeOffset));
  
    // Leave the frame (also dropping the register file).
    __ LeaveFrame(StackFrame::JAVA_SCRIPT);
  
    // Drop receiver + arguments.
    __ Daddu(sp, sp, args_count);
  }
  
  // Generate code for entering a JS function with the interpreter.
  // On entry to the function the receiver and arguments have been pushed on the
  // stack left to right.  The actual argument count matches the formal parameter
  // count expected by the function.
  //
  // The live registers are:
  //   o a1: the JS function object being called.
  //   o a3: the new target
  //   o cp: our context
  //   o fp: the caller's frame pointer
  //   o sp: stack pointer
  //   o ra: return address
  //
  // The function builds an interpreter frame.  See InterpreterFrameConstants in
  // frames.h for its layout.
  void Builtins::Generate_InterpreterEntryTrampoline(MacroAssembler* masm) {
    ProfileEntryHookStub::MaybeCallEntryHook(masm);
  
    // Open a frame scope to indicate that there is a frame on the stack.  The
    // MANUAL indicates that the scope shouldn't actually generate code to set up
    // the frame (that is done below).
    FrameScope frame_scope(masm, StackFrame::MANUAL);
    __ PushStandardFrame(a1);
  
    // Get the bytecode array from the function object (or from the DebugInfo if
    // it is present) and load it into kInterpreterBytecodeArrayRegister.
    __ ld(a0, FieldMemOperand(a1, JSFunction::kSharedFunctionInfoOffset));
    Label load_debug_bytecode_array, bytecode_array_loaded;
    Register debug_info = kInterpreterBytecodeArrayRegister;
    DCHECK(!debug_info.is(a0));
    __ ld(debug_info, FieldMemOperand(a0, SharedFunctionInfo::kDebugInfoOffset));
    __ Branch(&load_debug_bytecode_array, ne, debug_info,
              Operand(DebugInfo::uninitialized()));
    __ ld(kInterpreterBytecodeArrayRegister,
          FieldMemOperand(a0, SharedFunctionInfo::kFunctionDataOffset));
    __ bind(&bytecode_array_loaded);
  
    // Check whether we should continue to use the interpreter.
    Label switch_to_different_code_kind;
    __ ld(a0, FieldMemOperand(a0, SharedFunctionInfo::kCodeOffset));
    __ Branch(&switch_to_different_code_kind, ne, a0,
              Operand(masm->CodeObject()));  // Self-reference to this code.
  
    // Increment invocation count for the function.
    __ ld(a0, FieldMemOperand(a1, JSFunction::kLiteralsOffset));
    __ ld(a0, FieldMemOperand(a0, LiteralsArray::kFeedbackVectorOffset));
    __ ld(a4, FieldMemOperand(
                  a0, TypeFeedbackVector::kInvocationCountIndex * kPointerSize +
                          TypeFeedbackVector::kHeaderSize));
    __ Daddu(a4, a4, Operand(Smi::FromInt(1)));
    __ sd(a4, FieldMemOperand(
                  a0, TypeFeedbackVector::kInvocationCountIndex * kPointerSize +
                          TypeFeedbackVector::kHeaderSize));
  
    // Check function data field is actually a BytecodeArray object.
    if (FLAG_debug_code) {
      __ SmiTst(kInterpreterBytecodeArrayRegister, a4);
      __ Assert(ne, kFunctionDataShouldBeBytecodeArrayOnInterpreterEntry, a4,
                Operand(zero_reg));
      __ GetObjectType(kInterpreterBytecodeArrayRegister, a4, a4);
      __ Assert(eq, kFunctionDataShouldBeBytecodeArrayOnInterpreterEntry, a4,
                Operand(BYTECODE_ARRAY_TYPE));
    }
  
    // Reset code age.
    DCHECK_EQ(0, BytecodeArray::kNoAgeBytecodeAge);
    __ sb(zero_reg, FieldMemOperand(kInterpreterBytecodeArrayRegister,
                                    BytecodeArray::kBytecodeAgeOffset));
  
    // Load initial bytecode offset.
    __ li(kInterpreterBytecodeOffsetRegister,
          Operand(BytecodeArray::kHeaderSize - kHeapObjectTag));
  
    // Push new.target, bytecode array and Smi tagged bytecode array offset.
    __ SmiTag(a4, kInterpreterBytecodeOffsetRegister);
    __ Push(a3, kInterpreterBytecodeArrayRegister, a4);
  
    // Allocate the local and temporary register file on the stack.
    {
      // Load frame size (word) from the BytecodeArray object.
      __ lw(a4, FieldMemOperand(kInterpreterBytecodeArrayRegister,
                                BytecodeArray::kFrameSizeOffset));
  
      // Do a stack check to ensure we don't go over the limit.
      Label ok;
      __ Dsubu(a5, sp, Operand(a4));
      __ LoadRoot(a2, Heap::kRealStackLimitRootIndex);
      __ Branch(&ok, hs, a5, Operand(a2));
      __ CallRuntime(Runtime::kThrowStackOverflow);
      __ bind(&ok);
  
      // If ok, push undefined as the initial value for all register file entries.
      Label loop_header;
      Label loop_check;
      __ LoadRoot(a5, Heap::kUndefinedValueRootIndex);
      __ Branch(&loop_check);
      __ bind(&loop_header);
      // TODO(rmcilroy): Consider doing more than one push per loop iteration.
      __ push(a5);
      // Continue loop if not done.
      __ bind(&loop_check);
      __ Dsubu(a4, a4, Operand(kPointerSize));
      __ Branch(&loop_header, ge, a4, Operand(zero_reg));
    }
  
    // Load accumulator and dispatch table into registers.
    __ LoadRoot(kInterpreterAccumulatorRegister, Heap::kUndefinedValueRootIndex);
    __ li(kInterpreterDispatchTableRegister,
          Operand(ExternalReference::interpreter_dispatch_table_address(
              masm->isolate())));
  
    // Dispatch to the first bytecode handler for the function.
    __ Daddu(a0, kInterpreterBytecodeArrayRegister,
             kInterpreterBytecodeOffsetRegister);
    __ lbu(a0, MemOperand(a0));
    __ Dlsa(at, kInterpreterDispatchTableRegister, a0, kPointerSizeLog2);
    __ ld(at, MemOperand(at));
    __ Call(at);
    masm->isolate()->heap()->SetInterpreterEntryReturnPCOffset(masm->pc_offset());
  
    // The return value is in v0.
    LeaveInterpreterFrame(masm, t0);
    __ Jump(ra);
  
    // Load debug copy of the bytecode array.
    __ bind(&load_debug_bytecode_array);
    __ ld(kInterpreterBytecodeArrayRegister,
          FieldMemOperand(debug_info, DebugInfo::kDebugBytecodeArrayIndex));
    __ Branch(&bytecode_array_loaded);
  
    // If the shared code is no longer this entry trampoline, then the underlying
    // function has been switched to a different kind of code and we heal the
    // closure by switching the code entry field over to the new code as well.
    __ bind(&switch_to_different_code_kind);
    __ LeaveFrame(StackFrame::JAVA_SCRIPT);
    __ ld(a4, FieldMemOperand(a1, JSFunction::kSharedFunctionInfoOffset));
    __ ld(a4, FieldMemOperand(a4, SharedFunctionInfo::kCodeOffset));
    __ Daddu(a4, a4, Operand(Code::kHeaderSize - kHeapObjectTag));
    __ sd(a4, FieldMemOperand(a1, JSFunction::kCodeEntryOffset));
    __ RecordWriteCodeEntryField(a1, a4, a5);
    __ Jump(a4);
  }
  
  static void Generate_StackOverflowCheck(MacroAssembler* masm, Register num_args,
                                          Register scratch1, Register scratch2,
                                          Label* stack_overflow) {
    // Check the stack for overflow. We are not trying to catch
    // interruptions (e.g. debug break and preemption) here, so the "real stack
    // limit" is checked.
    __ LoadRoot(scratch1, Heap::kRealStackLimitRootIndex);
    // Make scratch1 the space we have left. The stack might already be overflowed
    // here which will cause scratch1 to become negative.
    __ dsubu(scratch1, sp, scratch1);
    // Check if the arguments will overflow the stack.
    __ dsll(scratch2, num_args, kPointerSizeLog2);
    // Signed comparison.
    __ Branch(stack_overflow, le, scratch1, Operand(scratch2));
  }
  
  static void Generate_InterpreterPushArgs(MacroAssembler* masm,
                                           Register num_args, Register index,
                                           Register scratch, Register scratch2,
                                           Label* stack_overflow) {
    //  Generate_StackOverflowCheck(masm, num_args, scratch, scratch2,
    //  stack_overflow);
  
    // Find the address of the last argument.
    __ mov(scratch2, num_args);
    __ dsll(scratch2, scratch2, kPointerSizeLog2);
    __ Dsubu(scratch2, index, Operand(scratch2));
  
    // Push the arguments.
    Label loop_header, loop_check;
    __ Branch(&loop_check);
    __ bind(&loop_header);
    __ ld(scratch, MemOperand(index));
    __ Daddu(index, index, Operand(-kPointerSize));
    __ push(scratch);
    __ bind(&loop_check);
    __ Branch(&loop_header, gt, index, Operand(scratch2));
  }
  
  // static
  void Builtins::Generate_InterpreterPushArgsAndCallImpl(
      MacroAssembler* masm, TailCallMode tail_call_mode,
      CallableType function_type) {
    // ----------- S t a t e -------------
    //  -- a0 : the number of arguments (not including the receiver)
    //  -- a2 : the address of the first argument to be pushed. Subsequent
    //          arguments should be consecutive above this, in the same order as
    //          they are to be pushed onto the stack.
    //  -- a1 : the target to call (can be any Object).
    // -----------------------------------
    Label stack_overflow;
  
    __ Daddu(a3, a0, Operand(1));  // Add one for receiver.
  
    // This function modifies a2, t0 and a4.
    Generate_InterpreterPushArgs(masm, a3, a2, a4, t0, &stack_overflow);
  
    // Call the target.
    if (function_type == CallableType::kJSFunction) {
      __ Jump(masm->isolate()->builtins()->CallFunction(ConvertReceiverMode::kAny,
                                                        tail_call_mode),
              RelocInfo::CODE_TARGET);
    } else {
      DCHECK_EQ(function_type, CallableType::kAny);
      __ Jump(masm->isolate()->builtins()->Call(ConvertReceiverMode::kAny,
                                                tail_call_mode),
              RelocInfo::CODE_TARGET);
    }
  
    __ bind(&stack_overflow);
    {
      __ TailCallRuntime(Runtime::kThrowStackOverflow);
      // Unreachable code.
      __ break_(0xCC);
    }
  }
  
  // static
  void Builtins::Generate_InterpreterPushArgsAndConstructImpl(
      MacroAssembler* masm, CallableType construct_type) {
    // ----------- S t a t e -------------
    // -- a0 : argument count (not including receiver)
    // -- a3 : new target
    // -- a1 : constructor to call
    // -- a2 : allocation site feedback if available, undefined otherwise.
    // -- a4 : address of the first argument
    // -----------------------------------
    Label stack_overflow;
  
    // Push a slot for the receiver.
    __ push(zero_reg);
  
    // This function modifies t0, a4 and a5.
    Generate_InterpreterPushArgs(masm, a0, a4, a5, t0, &stack_overflow);
  
    __ AssertUndefinedOrAllocationSite(a2, t0);
    if (construct_type == CallableType::kJSFunction) {
      __ AssertFunction(a1);
  
      // Tail call to the function-specific construct stub (still in the caller
      // context at this point).
      __ ld(a4, FieldMemOperand(a1, JSFunction::kSharedFunctionInfoOffset));
      __ ld(a4, FieldMemOperand(a4, SharedFunctionInfo::kConstructStubOffset));
      __ Daddu(at, a4, Operand(Code::kHeaderSize - kHeapObjectTag));
      __ Jump(at);
    } else {
      DCHECK_EQ(construct_type, CallableType::kAny);
      // Call the constructor with a0, a1, and a3 unmodified.
      __ Jump(masm->isolate()->builtins()->Construct(), RelocInfo::CODE_TARGET);
    }
  
    __ bind(&stack_overflow);
    {
      __ TailCallRuntime(Runtime::kThrowStackOverflow);
      // Unreachable code.
      __ break_(0xCC);
    }
  }
  
  // static
  void Builtins::Generate_InterpreterPushArgsAndConstructArray(
      MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- a0 : the number of arguments (not including the receiver)
    //  -- a1 : the target to call checked to be Array function.
    //  -- a2 : allocation site feedback.
    //  -- a3 : the address of the first argument to be pushed. Subsequent
    //          arguments should be consecutive above this, in the same order as
    //          they are to be pushed onto the stack.
    // -----------------------------------
    Label stack_overflow;
  
    __ Daddu(a4, a0, Operand(1));  // Add one for receiver.
  
    // This function modifies a3, a5 and a6.
    Generate_InterpreterPushArgs(masm, a4, a3, a5, a6, &stack_overflow);
  
    // ArrayConstructor stub expects constructor in a3. Set it here.
    __ mov(a3, a1);
  
    ArrayConstructorStub stub(masm->isolate());
    __ TailCallStub(&stub);
  
    __ bind(&stack_overflow);
    {
      __ TailCallRuntime(Runtime::kThrowStackOverflow);
      // Unreachable code.
      __ break_(0xCC);
    }
  }
  
  static void Generate_InterpreterEnterBytecode(MacroAssembler* masm) {
    // Set the return address to the correct point in the interpreter entry
    // trampoline.
    Smi* interpreter_entry_return_pc_offset(
        masm->isolate()->heap()->interpreter_entry_return_pc_offset());
    DCHECK_NE(interpreter_entry_return_pc_offset, Smi::kZero);
    __ li(t0, Operand(masm->isolate()->builtins()->InterpreterEntryTrampoline()));
    __ Daddu(ra, t0, Operand(interpreter_entry_return_pc_offset->value() +
                             Code::kHeaderSize - kHeapObjectTag));
  
    // Initialize the dispatch table register.
    __ li(kInterpreterDispatchTableRegister,
          Operand(ExternalReference::interpreter_dispatch_table_address(
              masm->isolate())));
  
    // Get the bytecode array pointer from the frame.
    __ ld(kInterpreterBytecodeArrayRegister,
          MemOperand(fp, InterpreterFrameConstants::kBytecodeArrayFromFp));
  
    if (FLAG_debug_code) {
      // Check function data field is actually a BytecodeArray object.
      __ SmiTst(kInterpreterBytecodeArrayRegister, at);
      __ Assert(ne, kFunctionDataShouldBeBytecodeArrayOnInterpreterEntry, at,
                Operand(zero_reg));
      __ GetObjectType(kInterpreterBytecodeArrayRegister, a1, a1);
      __ Assert(eq, kFunctionDataShouldBeBytecodeArrayOnInterpreterEntry, a1,
                Operand(BYTECODE_ARRAY_TYPE));
    }
  
    // Get the target bytecode offset from the frame.
    __ lw(
        kInterpreterBytecodeOffsetRegister,
        UntagSmiMemOperand(fp, InterpreterFrameConstants::kBytecodeOffsetFromFp));
  
    // Dispatch to the target bytecode.
    __ Daddu(a1, kInterpreterBytecodeArrayRegister,
             kInterpreterBytecodeOffsetRegister);
    __ lbu(a1, MemOperand(a1));
    __ Dlsa(a1, kInterpreterDispatchTableRegister, a1, kPointerSizeLog2);
    __ ld(a1, MemOperand(a1));
    __ Jump(a1);
  }
  
  void Builtins::Generate_InterpreterEnterBytecodeAdvance(MacroAssembler* masm) {
    // Advance the current bytecode offset stored within the given interpreter
    // stack frame. This simulates what all bytecode handlers do upon completion
    // of the underlying operation.
    __ ld(a1, MemOperand(fp, InterpreterFrameConstants::kBytecodeArrayFromFp));
    __ ld(a2, MemOperand(fp, InterpreterFrameConstants::kBytecodeOffsetFromFp));
    __ ld(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
    {
      FrameScope scope(masm, StackFrame::INTERNAL);
      __ Push(kInterpreterAccumulatorRegister, a1, a2);
      __ CallRuntime(Runtime::kInterpreterAdvanceBytecodeOffset);
      __ mov(a2, v0);  // Result is the new bytecode offset.
      __ Pop(kInterpreterAccumulatorRegister);
    }
    __ sd(a2, MemOperand(fp, InterpreterFrameConstants::kBytecodeOffsetFromFp));
  
    Generate_InterpreterEnterBytecode(masm);
  }
  
  void Builtins::Generate_InterpreterEnterBytecodeDispatch(MacroAssembler* masm) {
    Generate_InterpreterEnterBytecode(masm);
  }
  
  void Builtins::Generate_CompileLazy(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- a0 : argument count (preserved for callee)
    //  -- a3 : new target (preserved for callee)
    //  -- a1 : target function (preserved for callee)
    // -----------------------------------
    // First lookup code, maybe we don't need to compile!
    Label gotta_call_runtime, gotta_call_runtime_no_stack;
    Label try_shared;
    Label loop_top, loop_bottom;
  
    Register argument_count = a0;
    Register closure = a1;
    Register new_target = a3;
    __ push(argument_count);
    __ push(new_target);
    __ push(closure);
  
    Register map = a0;
    Register index = a2;
    __ ld(map, FieldMemOperand(closure, JSFunction::kSharedFunctionInfoOffset));
    __ ld(map, FieldMemOperand(map, SharedFunctionInfo::kOptimizedCodeMapOffset));
    __ ld(index, FieldMemOperand(map, FixedArray::kLengthOffset));
    __ Branch(&gotta_call_runtime, lt, index, Operand(Smi::FromInt(2)));
  
    // a3  : native context
    // a2  : length / index
    // a0  : optimized code map
    // stack[0] : new target
    // stack[4] : closure
    Register native_context = a3;
    __ ld(native_context, NativeContextMemOperand());
  
    __ bind(&loop_top);
    Register temp = a1;
    Register array_pointer = a5;
  
    // Does the native context match?
    __ SmiScale(at, index, kPointerSizeLog2);
    __ Daddu(array_pointer, map, Operand(at));
    __ ld(temp, FieldMemOperand(array_pointer,
                                SharedFunctionInfo::kOffsetToPreviousContext));
    __ ld(temp, FieldMemOperand(temp, WeakCell::kValueOffset));
    __ Branch(&loop_bottom, ne, temp, Operand(native_context));
  
    // Code available?
    Register entry = a4;
    __ ld(entry,
          FieldMemOperand(array_pointer,
                          SharedFunctionInfo::kOffsetToPreviousCachedCode));
    __ ld(entry, FieldMemOperand(entry, WeakCell::kValueOffset));
    __ JumpIfSmi(entry, &try_shared);
  
    // Found code. Get it into the closure and return.
    __ pop(closure);
    // Store code entry in the closure.
    __ Daddu(entry, entry, Operand(Code::kHeaderSize - kHeapObjectTag));
    __ sd(entry, FieldMemOperand(closure, JSFunction::kCodeEntryOffset));
    __ RecordWriteCodeEntryField(closure, entry, a5);
  
    // Link the closure into the optimized function list.
    // a4 : code entry
    // a3 : native context
    // a1 : closure
    __ ld(a5,
          ContextMemOperand(native_context, Context::OPTIMIZED_FUNCTIONS_LIST));
    __ sd(a5, FieldMemOperand(closure, JSFunction::kNextFunctionLinkOffset));
    __ RecordWriteField(closure, JSFunction::kNextFunctionLinkOffset, a5, a0,
                        kRAHasNotBeenSaved, kDontSaveFPRegs, EMIT_REMEMBERED_SET,
                        OMIT_SMI_CHECK);
    const int function_list_offset =
        Context::SlotOffset(Context::OPTIMIZED_FUNCTIONS_LIST);
    __ sd(closure,
          ContextMemOperand(native_context, Context::OPTIMIZED_FUNCTIONS_LIST));
    // Save closure before the write barrier.
    __ mov(a5, closure);
    __ RecordWriteContextSlot(native_context, function_list_offset, closure, a0,
                              kRAHasNotBeenSaved, kDontSaveFPRegs);
    __ mov(closure, a5);
    __ pop(new_target);
    __ pop(argument_count);
    __ Jump(entry);
  
    __ bind(&loop_bottom);
    __ Dsubu(index, index,
             Operand(Smi::FromInt(SharedFunctionInfo::kEntryLength)));
    __ Branch(&loop_top, gt, index, Operand(Smi::FromInt(1)));
  
    // We found no code.
    __ jmp(&gotta_call_runtime);
  
    __ bind(&try_shared);
    __ pop(closure);
    __ pop(new_target);
    __ pop(argument_count);
    __ ld(entry, FieldMemOperand(closure, JSFunction::kSharedFunctionInfoOffset));
    // Is the shared function marked for tier up?
    __ lbu(a5, FieldMemOperand(entry,
                               SharedFunctionInfo::kMarkedForTierUpByteOffset));
    __ And(a5, a5,
           Operand(1 << SharedFunctionInfo::kMarkedForTierUpBitWithinByte));
    __ Branch(&gotta_call_runtime_no_stack, ne, a5, Operand(zero_reg));
    // Is the full code valid?
    __ ld(entry, FieldMemOperand(entry, SharedFunctionInfo::kCodeOffset));
    __ lw(a5, FieldMemOperand(entry, Code::kFlagsOffset));
    __ And(a5, a5, Operand(Code::KindField::kMask));
    __ dsrl(a5, a5, Code::KindField::kShift);
    __ Branch(&gotta_call_runtime_no_stack, eq, a5, Operand(Code::BUILTIN));
    // Yes, install the full code.
    __ Daddu(entry, entry, Operand(Code::kHeaderSize - kHeapObjectTag));
    __ sd(entry, FieldMemOperand(closure, JSFunction::kCodeEntryOffset));
    __ RecordWriteCodeEntryField(closure, entry, a5);
    __ Jump(entry);
  
    __ bind(&gotta_call_runtime);
    __ pop(closure);
    __ pop(new_target);
    __ pop(argument_count);
    __ bind(&gotta_call_runtime_no_stack);
    GenerateTailCallToReturnedCode(masm, Runtime::kCompileLazy);
  }
  
  void Builtins::Generate_CompileBaseline(MacroAssembler* masm) {
    GenerateTailCallToReturnedCode(masm, Runtime::kCompileBaseline);
  }
  
  void Builtins::Generate_CompileOptimized(MacroAssembler* masm) {
    GenerateTailCallToReturnedCode(masm,
                                   Runtime::kCompileOptimized_NotConcurrent);
  }
  
  void Builtins::Generate_CompileOptimizedConcurrent(MacroAssembler* masm) {
    GenerateTailCallToReturnedCode(masm, Runtime::kCompileOptimized_Concurrent);
  }
  
  void Builtins::Generate_InstantiateAsmJs(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- a0 : argument count (preserved for callee)
    //  -- a1 : new target (preserved for callee)
    //  -- a3 : target function (preserved for callee)
    // -----------------------------------
    Label failed;
    {
      FrameScope scope(masm, StackFrame::INTERNAL);
      // Push a copy of the target function and the new target.
      // Push function as parameter to the runtime call.
      __ Move(t2, a0);
      __ SmiTag(a0);
      __ Push(a0, a1, a3, a1);
  
      // Copy arguments from caller (stdlib, foreign, heap).
      Label args_done;
      for (int j = 0; j < 4; ++j) {
        Label over;
        if (j < 3) {
          __ Branch(&over, ne, t2, Operand(j));
        }
        for (int i = j - 1; i >= 0; --i) {
          __ ld(t2, MemOperand(fp, StandardFrameConstants::kCallerSPOffset +
                                       i * kPointerSize));
          __ push(t2);
        }
        for (int i = 0; i < 3 - j; ++i) {
          __ PushRoot(Heap::kUndefinedValueRootIndex);
        }
        if (j < 3) {
          __ jmp(&args_done);
          __ bind(&over);
        }
      }
      __ bind(&args_done);
  
      // Call runtime, on success unwind frame, and parent frame.
      __ CallRuntime(Runtime::kInstantiateAsmJs, 4);
      // A smi 0 is returned on failure, an object on success.
      __ JumpIfSmi(v0, &failed);
  
      __ Drop(2);
      __ pop(t2);
      __ SmiUntag(t2);
      scope.GenerateLeaveFrame();
  
      __ Daddu(t2, t2, Operand(1));
      __ Dlsa(sp, sp, t2, kPointerSizeLog2);
      __ Ret();
  
      __ bind(&failed);
      // Restore target function and new target.
      __ Pop(a0, a1, a3);
      __ SmiUntag(a0);
    }
    // On failure, tail call back to regular js.
    GenerateTailCallToReturnedCode(masm, Runtime::kCompileLazy);
  }
  
  static void GenerateMakeCodeYoungAgainCommon(MacroAssembler* masm) {
    // For now, we are relying on the fact that make_code_young doesn't do any
    // garbage collection which allows us to save/restore the registers without
    // worrying about which of them contain pointers. We also don't build an
    // internal frame to make the code faster, since we shouldn't have to do stack
    // crawls in MakeCodeYoung. This seems a bit fragile.
  
    // Set a0 to point to the head of the PlatformCodeAge sequence.
    __ Dsubu(a0, a0, Operand(kNoCodeAgeSequenceLength - Assembler::kInstrSize));
  
    // The following registers must be saved and restored when calling through to
    // the runtime:
    //   a0 - contains return address (beginning of patch sequence)
    //   a1 - isolate
    //   a3 - new target
    RegList saved_regs =
        (a0.bit() | a1.bit() | a3.bit() | ra.bit() | fp.bit()) & ~sp.bit();
    FrameScope scope(masm, StackFrame::MANUAL);
    __ MultiPush(saved_regs);
    __ PrepareCallCFunction(2, 0, a2);
    __ li(a1, Operand(ExternalReference::isolate_address(masm->isolate())));
    __ CallCFunction(
        ExternalReference::get_make_code_young_function(masm->isolate()), 2);
    __ MultiPop(saved_regs);
    __ Jump(a0);
  }
  
  #define DEFINE_CODE_AGE_BUILTIN_GENERATOR(C)                              \
    void Builtins::Generate_Make##C##CodeYoungAgain(MacroAssembler* masm) { \
      GenerateMakeCodeYoungAgainCommon(masm);                               \
    }
  CODE_AGE_LIST(DEFINE_CODE_AGE_BUILTIN_GENERATOR)
  #undef DEFINE_CODE_AGE_BUILTIN_GENERATOR
  
  void Builtins::Generate_MarkCodeAsExecutedOnce(MacroAssembler* masm) {
    // For now, as in GenerateMakeCodeYoungAgainCommon, we are relying on the fact
    // that make_code_young doesn't do any garbage collection which allows us to
    // save/restore the registers without worrying about which of them contain
    // pointers.
  
    // Set a0 to point to the head of the PlatformCodeAge sequence.
    __ Dsubu(a0, a0, Operand(kNoCodeAgeSequenceLength - Assembler::kInstrSize));
  
    // The following registers must be saved and restored when calling through to
    // the runtime:
    //   a0 - contains return address (beginning of patch sequence)
    //   a1 - isolate
    //   a3 - new target
    RegList saved_regs =
        (a0.bit() | a1.bit() | a3.bit() | ra.bit() | fp.bit()) & ~sp.bit();
    FrameScope scope(masm, StackFrame::MANUAL);
    __ MultiPush(saved_regs);
    __ PrepareCallCFunction(2, 0, a2);
    __ li(a1, Operand(ExternalReference::isolate_address(masm->isolate())));
    __ CallCFunction(
        ExternalReference::get_mark_code_as_executed_function(masm->isolate()),
        2);
    __ MultiPop(saved_regs);
  
    // Perform prologue operations usually performed by the young code stub.
    __ PushStandardFrame(a1);
  
    // Jump to point after the code-age stub.
    __ Daddu(a0, a0, Operand((kNoCodeAgeSequenceLength)));
    __ Jump(a0);
  }
  
  void Builtins::Generate_MarkCodeAsExecutedTwice(MacroAssembler* masm) {
    GenerateMakeCodeYoungAgainCommon(masm);
  }
  
  void Builtins::Generate_MarkCodeAsToBeExecutedOnce(MacroAssembler* masm) {
    Generate_MarkCodeAsExecutedOnce(masm);
  }
  
  static void Generate_NotifyStubFailureHelper(MacroAssembler* masm,
                                               SaveFPRegsMode save_doubles) {
    {
      FrameScope scope(masm, StackFrame::INTERNAL);
  
      // Preserve registers across notification, this is important for compiled
      // stubs that tail call the runtime on deopts passing their parameters in
      // registers.
      __ MultiPush(kJSCallerSaved | kCalleeSaved);
      // Pass the function and deoptimization type to the runtime system.
      __ CallRuntime(Runtime::kNotifyStubFailure, save_doubles);
      __ MultiPop(kJSCallerSaved | kCalleeSaved);
    }
  
    __ Daddu(sp, sp, Operand(kPointerSize));  // Ignore state
    __ Jump(ra);                              // Jump to miss handler
  }
  
  void Builtins::Generate_NotifyStubFailure(MacroAssembler* masm) {
    Generate_NotifyStubFailureHelper(masm, kDontSaveFPRegs);
  }
  
  void Builtins::Generate_NotifyStubFailureSaveDoubles(MacroAssembler* masm) {
    Generate_NotifyStubFailureHelper(masm, kSaveFPRegs);
  }
  
  static void Generate_NotifyDeoptimizedHelper(MacroAssembler* masm,
                                               Deoptimizer::BailoutType type) {
    {
      FrameScope scope(masm, StackFrame::INTERNAL);
      // Pass the function and deoptimization type to the runtime system.
      __ li(a0, Operand(Smi::FromInt(static_cast<int>(type))));
      __ push(a0);
      __ CallRuntime(Runtime::kNotifyDeoptimized);
    }
  
    // Get the full codegen state from the stack and untag it -> a6.
    __ lw(a6, UntagSmiMemOperand(sp, 0 * kPointerSize));
    // Switch on the state.
    Label with_tos_register, unknown_state;
    __ Branch(
        &with_tos_register, ne, a6,
        Operand(static_cast<int64_t>(Deoptimizer::BailoutState::NO_REGISTERS)));
    __ Ret(USE_DELAY_SLOT);
    // Safe to fill delay slot Addu will emit one instruction.
    __ Daddu(sp, sp, Operand(1 * kPointerSize));  // Remove state.
  
    __ bind(&with_tos_register);
    DCHECK_EQ(kInterpreterAccumulatorRegister.code(), v0.code());
    __ ld(v0, MemOperand(sp, 1 * kPointerSize));
    __ Branch(
        &unknown_state, ne, a6,
        Operand(static_cast<int64_t>(Deoptimizer::BailoutState::TOS_REGISTER)));
  
    __ Ret(USE_DELAY_SLOT);
    // Safe to fill delay slot Addu will emit one instruction.
    __ Daddu(sp, sp, Operand(2 * kPointerSize));  // Remove state.
  
    __ bind(&unknown_state);
    __ stop("no cases left");
  }
  
  void Builtins::Generate_NotifyDeoptimized(MacroAssembler* masm) {
    Generate_NotifyDeoptimizedHelper(masm, Deoptimizer::EAGER);
  }
  
  void Builtins::Generate_NotifySoftDeoptimized(MacroAssembler* masm) {
    Generate_NotifyDeoptimizedHelper(masm, Deoptimizer::SOFT);
  }
  
  void Builtins::Generate_NotifyLazyDeoptimized(MacroAssembler* masm) {
    Generate_NotifyDeoptimizedHelper(masm, Deoptimizer::LAZY);
  }
  
  // Clobbers {t2, t3, a4, a5}.
  static void CompatibleReceiverCheck(MacroAssembler* masm, Register receiver,
                                      Register function_template_info,
                                      Label* receiver_check_failed) {
    Register signature = t2;
    Register map = t3;
    Register constructor = a4;
    Register scratch = a5;
  
    // If there is no signature, return the holder.
    __ ld(signature, FieldMemOperand(function_template_info,
                                     FunctionTemplateInfo::kSignatureOffset));
    Label receiver_check_passed;
    __ JumpIfRoot(signature, Heap::kUndefinedValueRootIndex,
                  &receiver_check_passed);
  
    // Walk the prototype chain.
    __ ld(map, FieldMemOperand(receiver, HeapObject::kMapOffset));
    Label prototype_loop_start;
    __ bind(&prototype_loop_start);
  
    // Get the constructor, if any.
    __ GetMapConstructor(constructor, map, scratch, scratch);
    Label next_prototype;
    __ Branch(&next_prototype, ne, scratch, Operand(JS_FUNCTION_TYPE));
    Register type = constructor;
    __ ld(type,
          FieldMemOperand(constructor, JSFunction::kSharedFunctionInfoOffset));
    __ ld(type, FieldMemOperand(type, SharedFunctionInfo::kFunctionDataOffset));
  
    // Loop through the chain of inheriting function templates.
    Label function_template_loop;
    __ bind(&function_template_loop);
  
    // If the signatures match, we have a compatible receiver.
    __ Branch(&receiver_check_passed, eq, signature, Operand(type),
              USE_DELAY_SLOT);
  
    // If the current type is not a FunctionTemplateInfo, load the next prototype
    // in the chain.
    __ JumpIfSmi(type, &next_prototype);
    __ GetObjectType(type, scratch, scratch);
    __ Branch(&next_prototype, ne, scratch, Operand(FUNCTION_TEMPLATE_INFO_TYPE));
  
    // Otherwise load the parent function template and iterate.
    __ ld(type,
          FieldMemOperand(type, FunctionTemplateInfo::kParentTemplateOffset));
    __ Branch(&function_template_loop);
  
    // Load the next prototype.
    __ bind(&next_prototype);
    __ lwu(scratch, FieldMemOperand(map, Map::kBitField3Offset));
    __ DecodeField<Map::HasHiddenPrototype>(scratch);
    __ Branch(receiver_check_failed, eq, scratch, Operand(zero_reg));
  
    __ ld(receiver, FieldMemOperand(map, Map::kPrototypeOffset));
    __ ld(map, FieldMemOperand(receiver, HeapObject::kMapOffset));
    // Iterate.
    __ Branch(&prototype_loop_start);
  
    __ bind(&receiver_check_passed);
  }
  
  void Builtins::Generate_HandleFastApiCall(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- a0                 : number of arguments excluding receiver
    //  -- a1                 : callee
    //  -- ra                 : return address
    //  -- sp[0]              : last argument
    //  -- ...
    //  -- sp[8 * (argc - 1)] : first argument
    //  -- sp[8 * argc]       : receiver
    // -----------------------------------
  
    // Load the FunctionTemplateInfo.
    __ ld(t1, FieldMemOperand(a1, JSFunction::kSharedFunctionInfoOffset));
    __ ld(t1, FieldMemOperand(t1, SharedFunctionInfo::kFunctionDataOffset));
  
    // Do the compatible receiver check
    Label receiver_check_failed;
    __ Dlsa(t8, sp, a0, kPointerSizeLog2);
    __ ld(t0, MemOperand(t8));
    CompatibleReceiverCheck(masm, t0, t1, &receiver_check_failed);
  
    // Get the callback offset from the FunctionTemplateInfo, and jump to the
    // beginning of the code.
    __ ld(t2, FieldMemOperand(t1, FunctionTemplateInfo::kCallCodeOffset));
    __ ld(t2, FieldMemOperand(t2, CallHandlerInfo::kFastHandlerOffset));
    __ Daddu(t2, t2, Operand(Code::kHeaderSize - kHeapObjectTag));
    __ Jump(t2);
  
    // Compatible receiver check failed: throw an Illegal Invocation exception.
    __ bind(&receiver_check_failed);
    // Drop the arguments (including the receiver);
    __ Daddu(t8, t8, Operand(kPointerSize));
    __ daddu(sp, t8, zero_reg);
    __ TailCallRuntime(Runtime::kThrowIllegalInvocation);
  }
  
  static void Generate_OnStackReplacementHelper(MacroAssembler* masm,
                                                bool has_handler_frame) {
    // Lookup the function in the JavaScript frame.
    if (has_handler_frame) {
      __ ld(a0, MemOperand(fp, StandardFrameConstants::kCallerFPOffset));
      __ ld(a0, MemOperand(a0, JavaScriptFrameConstants::kFunctionOffset));
    } else {
      __ ld(a0, MemOperand(fp, JavaScriptFrameConstants::kFunctionOffset));
    }
  
    {
      FrameScope scope(masm, StackFrame::INTERNAL);
      // Pass function as argument.
      __ push(a0);
      __ CallRuntime(Runtime::kCompileForOnStackReplacement);
    }
  
    // If the code object is null, just return to the caller.
    __ Ret(eq, v0, Operand(Smi::kZero));
  
    // Drop any potential handler frame that is be sitting on top of the actual
    // JavaScript frame. This is the case then OSR is triggered from bytecode.
    if (has_handler_frame) {
      __ LeaveFrame(StackFrame::STUB);
    }
  
    // Load deoptimization data from the code object.
    // <deopt_data> = <code>[#deoptimization_data_offset]
    __ ld(a1, MemOperand(v0, Code::kDeoptimizationDataOffset - kHeapObjectTag));
  
    // Load the OSR entrypoint offset from the deoptimization data.
    // <osr_offset> = <deopt_data>[#header_size + #osr_pc_offset]
    __ lw(a1,
          UntagSmiMemOperand(a1, FixedArray::OffsetOfElementAt(
                                     DeoptimizationInputData::kOsrPcOffsetIndex) -
                                     kHeapObjectTag));
  
    // Compute the target address = code_obj + header_size + osr_offset
    // <entry_addr> = <code_obj> + #header_size + <osr_offset>
    __ daddu(v0, v0, a1);
    __ daddiu(ra, v0, Code::kHeaderSize - kHeapObjectTag);
  
    // And "return" to the OSR entry point of the function.
    __ Ret();
  }
  
  void Builtins::Generate_OnStackReplacement(MacroAssembler* masm) {
    Generate_OnStackReplacementHelper(masm, false);
  }
  
  void Builtins::Generate_InterpreterOnStackReplacement(MacroAssembler* masm) {
    Generate_OnStackReplacementHelper(masm, true);
  }
  
  // static
  void Builtins::Generate_FunctionPrototypeApply(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- a0    : argc
    //  -- sp[0] : argArray
    //  -- sp[4] : thisArg
    //  -- sp[8] : receiver
    // -----------------------------------
  
    Register argc = a0;
    Register arg_array = a0;
    Register receiver = a1;
    Register this_arg = a2;
    Register undefined_value = a3;
    Register scratch = a4;
  
    __ LoadRoot(undefined_value, Heap::kUndefinedValueRootIndex);
    // 1. Load receiver into a1, argArray into a0 (if present), remove all
    // arguments from the stack (including the receiver), and push thisArg (if
    // present) instead.
    {
      // Claim (2 - argc) dummy arguments form the stack, to put the stack in a
      // consistent state for a simple pop operation.
  
      __ Dsubu(sp, sp, Operand(2 * kPointerSize));
      __ Dlsa(sp, sp, argc, kPointerSizeLog2);
      __ mov(scratch, argc);
      __ Pop(this_arg, arg_array);                   // Overwrite argc
      __ Movz(arg_array, undefined_value, scratch);  // if argc == 0
      __ Movz(this_arg, undefined_value, scratch);   // if argc == 0
      __ Dsubu(scratch, scratch, Operand(1));
      __ Movz(arg_array, undefined_value, scratch);  // if argc == 1
      __ ld(receiver, MemOperand(sp));
      __ sd(this_arg, MemOperand(sp));
    }
  
    // ----------- S t a t e -------------
    //  -- a0    : argArray
    //  -- a1    : receiver
    //  -- a3    : undefined root value
    //  -- sp[0] : thisArg
    // -----------------------------------
  
    // 2. Make sure the receiver is actually callable.
    Label receiver_not_callable;
    __ JumpIfSmi(receiver, &receiver_not_callable);
    __ ld(a4, FieldMemOperand(receiver, HeapObject::kMapOffset));
    __ lbu(a4, FieldMemOperand(a4, Map::kBitFieldOffset));
    __ And(a4, a4, Operand(1 << Map::kIsCallable));
    __ Branch(&receiver_not_callable, eq, a4, Operand(zero_reg));
  
    // 3. Tail call with no arguments if argArray is null or undefined.
    Label no_arguments;
    __ JumpIfRoot(arg_array, Heap::kNullValueRootIndex, &no_arguments);
    __ Branch(&no_arguments, eq, arg_array, Operand(undefined_value));
  
    // 4a. Apply the receiver to the given argArray (passing undefined for
    // new.target).
    DCHECK(undefined_value.is(a3));
    __ 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);
    {
      __ mov(a0, zero_reg);
      DCHECK(receiver.is(a1));
      __ Jump(masm->isolate()->builtins()->Call(), RelocInfo::CODE_TARGET);
    }
  
    // 4c. The receiver is not callable, throw an appropriate TypeError.
    __ bind(&receiver_not_callable);
    {
      __ sd(receiver, MemOperand(sp));
      __ TailCallRuntime(Runtime::kThrowApplyNonFunction);
    }
  }
  
  // static
  void Builtins::Generate_FunctionPrototypeCall(MacroAssembler* masm) {
    // 1. Make sure we have at least one argument.
    // a0: actual number of arguments
    {
      Label done;
      __ Branch(&done, ne, a0, Operand(zero_reg));
      __ PushRoot(Heap::kUndefinedValueRootIndex);
      __ Daddu(a0, a0, Operand(1));
      __ bind(&done);
    }
  
    // 2. Get the function to call (passed as receiver) from the stack.
    // a0: actual number of arguments
    __ Dlsa(at, sp, a0, kPointerSizeLog2);
    __ ld(a1, MemOperand(at));
  
    // 3. Shift arguments and return address one slot down on the stack
    //    (overwriting the original receiver).  Adjust argument count to make
    //    the original first argument the new receiver.
    // a0: actual number of arguments
    // a1: function
    {
      Label loop;
      // Calculate the copy start address (destination). Copy end address is sp.
      __ Dlsa(a2, sp, a0, kPointerSizeLog2);
  
      __ bind(&loop);
      __ ld(at, MemOperand(a2, -kPointerSize));
      __ sd(at, MemOperand(a2));
      __ Dsubu(a2, a2, Operand(kPointerSize));
      __ Branch(&loop, ne, a2, Operand(sp));
      // Adjust the actual number of arguments and remove the top element
      // (which is a copy of the last argument).
      __ Dsubu(a0, a0, Operand(1));
      __ Pop();
    }
  
    // 4. Call the callable.
    __ Jump(masm->isolate()->builtins()->Call(), RelocInfo::CODE_TARGET);
  }
  
  void Builtins::Generate_ReflectApply(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- a0     : argc
    //  -- sp[0]  : argumentsList  (if argc ==3)
    //  -- sp[4]  : thisArgument   (if argc >=2)
    //  -- sp[8]  : target         (if argc >=1)
    //  -- sp[12] : receiver
    // -----------------------------------
  
    Register argc = a0;
    Register arguments_list = a0;
    Register target = a1;
    Register this_argument = a2;
    Register undefined_value = a3;
    Register scratch = a4;
  
    __ LoadRoot(undefined_value, Heap::kUndefinedValueRootIndex);
    // 1. Load target into a1 (if present), argumentsList into a0 (if present),
    // remove all arguments from the stack (including the receiver), and push
    // thisArgument (if present) instead.
    {
      // Claim (3 - argc) dummy arguments form the stack, to put the stack in a
      // consistent state for a simple pop operation.
  
      __ Dsubu(sp, sp, Operand(3 * kPointerSize));
      __ Dlsa(sp, sp, argc, kPointerSizeLog2);
      __ mov(scratch, argc);
      __ Pop(target, this_argument, arguments_list);
      __ Movz(arguments_list, undefined_value, scratch);  // if argc == 0
      __ Movz(this_argument, undefined_value, scratch);   // if argc == 0
      __ Movz(target, undefined_value, scratch);          // if argc == 0
      __ Dsubu(scratch, scratch, Operand(1));
      __ Movz(arguments_list, undefined_value, scratch);  // if argc == 1
      __ Movz(this_argument, undefined_value, scratch);   // if argc == 1
      __ Dsubu(scratch, scratch, Operand(1));
      __ Movz(arguments_list, undefined_value, scratch);  // if argc == 2
  
      __ sd(this_argument, MemOperand(sp, 0));  // Overwrite receiver
    }
  
    // ----------- S t a t e -------------
    //  -- a0    : argumentsList
    //  -- a1    : target
    //  -- a3    : undefined root value
    //  -- sp[0] : thisArgument
    // -----------------------------------
  
    // 2. Make sure the target is actually callable.
    Label target_not_callable;
    __ JumpIfSmi(target, &target_not_callable);
    __ ld(a4, FieldMemOperand(target, HeapObject::kMapOffset));
    __ lbu(a4, FieldMemOperand(a4, Map::kBitFieldOffset));
    __ And(a4, a4, Operand(1 << Map::kIsCallable));
    __ Branch(&target_not_callable, eq, a4, Operand(zero_reg));
  
    // 3a. Apply the target to the given argumentsList (passing undefined for
    // new.target).
    DCHECK(undefined_value.is(a3));
    __ Jump(masm->isolate()->builtins()->Apply(), RelocInfo::CODE_TARGET);
  
    // 3b. The target is not callable, throw an appropriate TypeError.
    __ bind(&target_not_callable);
    {
      __ sd(target, MemOperand(sp));
      __ TailCallRuntime(Runtime::kThrowApplyNonFunction);
    }
  }
  
  void Builtins::Generate_ReflectConstruct(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- a0     : argc
    //  -- sp[0]  : new.target (optional) (dummy value if argc <= 2)
    //  -- sp[4]  : argumentsList         (dummy value if argc <= 1)
    //  -- sp[8]  : target                (dummy value if argc == 0)
    //  -- sp[12] : receiver
    // -----------------------------------
    Register argc = a0;
    Register arguments_list = a0;
    Register target = a1;
    Register new_target = a3;
    Register undefined_value = a4;
    Register scratch = a5;
  
    // 1. Load target into a1 (if present), argumentsList into a0 (if present),
    // new.target into a3 (if present, otherwise use target), remove all
    // arguments from the stack (including the receiver), and push thisArgument
    // (if present) instead.
    {
      // Claim (3 - argc) dummy arguments form the stack, to put the stack in a
      // consistent state for a simple pop operation.
  
      __ Dsubu(sp, sp, Operand(3 * kPointerSize));
      __ Dlsa(sp, sp, argc, kPointerSizeLog2);
      __ mov(scratch, argc);
      __ Pop(target, arguments_list, new_target);
      __ Movz(arguments_list, undefined_value, scratch);  // if argc == 0
      __ Movz(new_target, undefined_value, scratch);      // if argc == 0
      __ Movz(target, undefined_value, scratch);          // if argc == 0
      __ Dsubu(scratch, scratch, Operand(1));
      __ Movz(arguments_list, undefined_value, scratch);  // if argc == 1
      __ Movz(new_target, target, scratch);               // if argc == 1
      __ Dsubu(scratch, scratch, Operand(1));
      __ Movz(new_target, target, scratch);  // if argc == 2
  
      __ sd(undefined_value, MemOperand(sp, 0));  // Overwrite receiver
    }
  
    // ----------- S t a t e -------------
    //  -- a0    : argumentsList
    //  -- a1    : target
    //  -- a3    : new.target
    //  -- sp[0] : receiver (undefined)
    // -----------------------------------
  
    // 2. Make sure the target is actually a constructor.
    Label target_not_constructor;
    __ JumpIfSmi(target, &target_not_constructor);
    __ ld(a4, FieldMemOperand(target, HeapObject::kMapOffset));
    __ lbu(a4, FieldMemOperand(a4, Map::kBitFieldOffset));
    __ And(a4, a4, Operand(1 << Map::kIsConstructor));
    __ Branch(&target_not_constructor, eq, a4, Operand(zero_reg));
  
    // 3. Make sure the target is actually a constructor.
    Label new_target_not_constructor;
    __ JumpIfSmi(new_target, &new_target_not_constructor);
    __ ld(a4, FieldMemOperand(new_target, HeapObject::kMapOffset));
    __ lbu(a4, FieldMemOperand(a4, Map::kBitFieldOffset));
    __ And(a4, a4, Operand(1 << Map::kIsConstructor));
    __ Branch(&new_target_not_constructor, eq, a4, Operand(zero_reg));
  
    // 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);
    {
      __ sd(target, MemOperand(sp));
      __ TailCallRuntime(Runtime::kThrowCalledNonCallable);
    }
  
    // 4c. The new.target is not a constructor, throw an appropriate TypeError.
    __ bind(&new_target_not_constructor);
    {
      __ sd(new_target, MemOperand(sp));
      __ TailCallRuntime(Runtime::kThrowCalledNonCallable);
    }
  }
  
  static void EnterArgumentsAdaptorFrame(MacroAssembler* masm) {
    // __ sll(a0, a0, kSmiTagSize);
    __ dsll32(a0, a0, 0);
    __ li(a4, Operand(Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR)));
    __ MultiPush(a0.bit() | a1.bit() | a4.bit() | fp.bit() | ra.bit());
    __ Daddu(fp, sp, Operand(StandardFrameConstants::kFixedFrameSizeFromFp +
                             kPointerSize));
  }
  
  static void LeaveArgumentsAdaptorFrame(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- v0 : result being passed through
    // -----------------------------------
    // Get the number of arguments passed (as a smi), tear down the frame and
    // then tear down the parameters.
    __ ld(a1, MemOperand(fp, -(StandardFrameConstants::kFixedFrameSizeFromFp +
                               kPointerSize)));
    __ mov(sp, fp);
    __ MultiPop(fp.bit() | ra.bit());
    __ SmiScale(a4, a1, kPointerSizeLog2);
    __ Daddu(sp, sp, a4);
    // Adjust for the receiver.
    __ Daddu(sp, sp, Operand(kPointerSize));
  }
  
  // static
  void Builtins::Generate_Apply(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- a0    : argumentsList
    //  -- a1    : target
    //  -- a3    : new.target (checked to be constructor or undefined)
    //  -- sp[0] : thisArgument
    // -----------------------------------
  
    Register arguments_list = a0;
    Register target = a1;
    Register new_target = a3;
  
    Register args = a0;
    Register len = a2;
  
    // Create the list of arguments from the array-like argumentsList.
    {
      Label create_arguments, create_array, create_holey_array, create_runtime,
          done_create;
      __ JumpIfSmi(arguments_list, &create_runtime);
  
      // Load the map of argumentsList into a2.
      Register arguments_list_map = a2;
      __ ld(arguments_list_map,
            FieldMemOperand(arguments_list, HeapObject::kMapOffset));
  
      // Load native context into a4.
      Register native_context = a4;
      __ ld(native_context, NativeContextMemOperand());
  
      // Check if argumentsList is an (unmodified) arguments object.
      __ ld(at, ContextMemOperand(native_context,
                                  Context::SLOPPY_ARGUMENTS_MAP_INDEX));
      __ Branch(&create_arguments, eq, arguments_list_map, Operand(at));
      __ ld(at, ContextMemOperand(native_context,
                                  Context::STRICT_ARGUMENTS_MAP_INDEX));
      __ Branch(&create_arguments, eq, arguments_list_map, Operand(at));
  
      // Check if argumentsList is a fast JSArray.
      __ ld(v0, FieldMemOperand(a2, HeapObject::kMapOffset));
      __ lbu(v0, FieldMemOperand(v0, Map::kInstanceTypeOffset));
      __ Branch(&create_array, eq, v0, Operand(JS_ARRAY_TYPE));
  
      // Ask the runtime to create the list (actually a FixedArray).
      __ bind(&create_runtime);
      {
        FrameScope scope(masm, StackFrame::INTERNAL);
        __ Push(target, new_target, arguments_list);
        __ CallRuntime(Runtime::kCreateListFromArrayLike);
        __ mov(arguments_list, v0);
        __ Pop(target, new_target);
        __ lw(len, UntagSmiFieldMemOperand(v0, FixedArray::kLengthOffset));
      }
      __ Branch(&done_create);
  
      // Try to create the list from an arguments object.
      __ bind(&create_arguments);
      __ lw(len, UntagSmiFieldMemOperand(arguments_list,
                                         JSArgumentsObject::kLengthOffset));
      __ ld(a4, FieldMemOperand(arguments_list, JSObject::kElementsOffset));
      __ lw(at, UntagSmiFieldMemOperand(a4, FixedArray::kLengthOffset));
      __ Branch(&create_runtime, ne, len, Operand(at));
      __ mov(args, a4);
  
      __ Branch(&done_create);
  
      // For holey JSArrays we need to check that the array prototype chain
      // protector is intact and our prototype is the Array.prototype actually.
      __ bind(&create_holey_array);
      __ ld(a2, FieldMemOperand(a2, Map::kPrototypeOffset));
      __ ld(at, ContextMemOperand(t0, Context::INITIAL_ARRAY_PROTOTYPE_INDEX));
      __ Branch(&create_runtime, ne, a2, Operand(at));
      __ LoadRoot(at, Heap::kArrayProtectorRootIndex);
      __ lw(a2, UntagSmiFieldMemOperand(at, PropertyCell::kValueOffset));
      __ Branch(&create_runtime, ne, a2,
                Operand(Smi::FromInt(Isolate::kProtectorValid)));
      __ lw(a2, UntagSmiFieldMemOperand(a0, JSArray::kLengthOffset));
      __ ld(a0, FieldMemOperand(a0, JSArray::kElementsOffset));
      __ Branch(&done_create);
  
      // Try to create the list from a JSArray object.
      __ bind(&create_array);
      __ ld(a2, FieldMemOperand(a2, Map::kBitField2Offset));
      __ DecodeField<Map::ElementsKindBits>(a2);
      STATIC_ASSERT(FAST_SMI_ELEMENTS == 0);
      STATIC_ASSERT(FAST_ELEMENTS == 2);
      STATIC_ASSERT(FAST_HOLEY_ELEMENTS == 3);
      __ Branch(&create_holey_array, eq, a2, Operand(FAST_HOLEY_SMI_ELEMENTS));
      __ Branch(&create_holey_array, eq, a2, Operand(FAST_HOLEY_ELEMENTS));
      __ andi(a2, a2, uint16_t(~FAST_ELEMENTS));  // works if enum ElementsKind
      // has less than 2^16 elements
      __ Branch(&create_runtime, ne, a2, Operand(int64_t(0)));
      __ lw(a2, UntagSmiFieldMemOperand(arguments_list, JSArray::kLengthOffset));
      __ ld(a0, FieldMemOperand(arguments_list, 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(a4, Heap::kRealStackLimitRootIndex);
      // Make ip the space we have left. The stack might already be overflowed
      // here which will cause ip to become negative.
      __ Dsubu(a4, sp, a4);
      // Check if the arguments will overflow the stack.
      __ dsll(at, len, kPointerSizeLog2);
      __ Branch(&done, gt, a4, Operand(at));  // Signed comparison.
      __ TailCallRuntime(Runtime::kThrowStackOverflow);
      __ bind(&done);
    }
  
    // ----------- S t a t e -------------
    //  -- a1    : target
    //  -- a0    : args (a FixedArray built from argumentsList)
    //  -- a2    : len (number of elements to push from args)
    //  -- a3    : new.target (checked to be constructor or undefined)
    //  -- sp[0] : thisArgument
    // -----------------------------------
  
    // Push arguments onto the stack (thisArgument is already on the stack).
    {
      Label done, push, loop;
      Register src = a4;
      Register scratch = len;
  
      __ daddiu(src, args, FixedArray::kHeaderSize - kHeapObjectTag);
      __ Branch(&done, eq, len, Operand(zero_reg), i::USE_DELAY_SLOT);
      __ mov(a0, len);  // The 'len' argument for Call() or Construct().
      __ dsll(scratch, len, kPointerSizeLog2);
      __ Dsubu(scratch, sp, Operand(scratch));
      __ LoadRoot(t1, Heap::kTheHoleValueRootIndex);
      __ bind(&loop);
      __ ld(a5, MemOperand(src));
      __ Branch(&push, ne, a5, Operand(t1));
      __ LoadRoot(a5, Heap::kUndefinedValueRootIndex);
      __ bind(&push);
      __ daddiu(src, src, kPointerSize);
      __ Push(a5);
      __ Branch(&loop, ne, scratch, Operand(sp));
      __ bind(&done);
    }
  
    // ----------- S t a t e -------------
    //  -- a0             : argument count (len)
    //  -- a1             : target
    //  -- a3             : new.target (checked to be constructor or undefinded)
    //  -- sp[0]          : args[len-1]
    //  -- sp[8]          : args[len-2]
    //     ...            : ...
    //  -- sp[8*(len-2)]  : args[1]
    //  -- sp[8*(len-1)]  : args[0]
    //  ----------------------------------
  
    // Dispatch to Call or Construct depending on whether new.target is undefined.
    {
      Label construct;
      __ LoadRoot(at, Heap::kUndefinedValueRootIndex);
      __ Branch(&construct, ne, a3, Operand(at));
      __ Jump(masm->isolate()->builtins()->Call(), RelocInfo::CODE_TARGET);
      __ bind(&construct);
      __ Jump(masm->isolate()->builtins()->Construct(), RelocInfo::CODE_TARGET);
    }
  }
  
  namespace {
  
  // Drops top JavaScript frame and an arguments adaptor frame below it (if
  // present) preserving all the arguments prepared for current call.
  // Does nothing if debugger is currently active.
  // ES6 14.6.3. PrepareForTailCall
  //
  // Stack structure for the function g() tail calling f():
  //
  // ------- Caller frame: -------
  // |  ...
  // |  g()'s arg M
  // |  ...
  // |  g()'s arg 1
  // |  g()'s receiver arg
  // |  g()'s caller pc
  // ------- g()'s frame: -------
  // |  g()'s caller fp      <- fp
  // |  g()'s context
  // |  function pointer: g
  // |  -------------------------
  // |  ...
  // |  ...
  // |  f()'s arg N
  // |  ...
  // |  f()'s arg 1
  // |  f()'s receiver arg   <- sp (f()'s caller pc is not on the stack yet!)
  // ----------------------
  //
  void PrepareForTailCall(MacroAssembler* masm, Register args_reg,
                          Register scratch1, Register scratch2,
                          Register scratch3) {
    DCHECK(!AreAliased(args_reg, scratch1, scratch2, scratch3));
    Comment cmnt(masm, "[ PrepareForTailCall");
  
    // Prepare for tail call only if ES2015 tail call elimination is enabled.
    Label done;
    ExternalReference is_tail_call_elimination_enabled =
        ExternalReference::is_tail_call_elimination_enabled_address(
            masm->isolate());
    __ li(at, Operand(is_tail_call_elimination_enabled));
    __ lb(scratch1, MemOperand(at));
    __ Branch(&done, eq, scratch1, Operand(zero_reg));
  
    // Drop possible interpreter handler/stub frame.
    {
      Label no_interpreter_frame;
      __ ld(scratch3,
            MemOperand(fp, CommonFrameConstants::kContextOrFrameTypeOffset));
      __ Branch(&no_interpreter_frame, ne, scratch3,
                Operand(Smi::FromInt(StackFrame::STUB)));
      __ ld(fp, MemOperand(fp, StandardFrameConstants::kCallerFPOffset));
      __ bind(&no_interpreter_frame);
    }
  
    // Check if next frame is an arguments adaptor frame.
    Register caller_args_count_reg = scratch1;
    Label no_arguments_adaptor, formal_parameter_count_loaded;
    __ ld(scratch2, MemOperand(fp, StandardFrameConstants::kCallerFPOffset));
    __ ld(scratch3,
          MemOperand(scratch2, CommonFrameConstants::kContextOrFrameTypeOffset));
    __ Branch(&no_arguments_adaptor, ne, scratch3,
              Operand(Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR)));
  
    // Drop current frame and load arguments count from arguments adaptor frame.
    __ mov(fp, scratch2);
    __ lw(caller_args_count_reg,
          UntagSmiMemOperand(fp, ArgumentsAdaptorFrameConstants::kLengthOffset));
    __ Branch(&formal_parameter_count_loaded);
  
    __ bind(&no_arguments_adaptor);
    // Load caller's formal parameter count
    __ ld(scratch1,
          MemOperand(fp, ArgumentsAdaptorFrameConstants::kFunctionOffset));
    __ ld(scratch1,
          FieldMemOperand(scratch1, JSFunction::kSharedFunctionInfoOffset));
    __ lw(caller_args_count_reg,
          FieldMemOperand(scratch1,
                          SharedFunctionInfo::kFormalParameterCountOffset));
  
    __ bind(&formal_parameter_count_loaded);
  
    ParameterCount callee_args_count(args_reg);
    __ PrepareForTailCall(callee_args_count, caller_args_count_reg, scratch2,
                          scratch3);
    __ bind(&done);
  }
  }  // namespace
  
  // static
  void Builtins::Generate_CallFunction(MacroAssembler* masm,
                                       ConvertReceiverMode mode,
                                       TailCallMode tail_call_mode) {
    // ----------- S t a t e -------------
    //  -- a0 : the number of arguments (not including the receiver)
    //  -- a1 : the function to call (checked to be a JSFunction)
    // -----------------------------------
    __ AssertFunction(a1);
  
    // See ES6 section 9.2.1 [[Call]] ( thisArgument, argumentsList)
    // Check that function is not a "classConstructor".
    Label class_constructor;
    __ ld(a2, FieldMemOperand(a1, JSFunction::kSharedFunctionInfoOffset));
    __ lbu(a3, FieldMemOperand(a2, SharedFunctionInfo::kFunctionKindByteOffset));
    __ And(at, a3, Operand(SharedFunctionInfo::kClassConstructorBitsWithinByte));
    __ Branch(&class_constructor, ne, at, Operand(zero_reg));
  
    // Enter the context of the function; ToObject has to run in the function
    // context, and we also need to take the global proxy from the function
    // context in case of conversion.
    STATIC_ASSERT(SharedFunctionInfo::kNativeByteOffset ==
                  SharedFunctionInfo::kStrictModeByteOffset);
    __ ld(cp, FieldMemOperand(a1, JSFunction::kContextOffset));
    // We need to convert the receiver for non-native sloppy mode functions.
    Label done_convert;
    __ lbu(a3, FieldMemOperand(a2, SharedFunctionInfo::kNativeByteOffset));
    __ And(at, a3, Operand((1 << SharedFunctionInfo::kNativeBitWithinByte) |
                           (1 << SharedFunctionInfo::kStrictModeBitWithinByte)));
    __ Branch(&done_convert, ne, at, Operand(zero_reg));
    {
      // ----------- S t a t e -------------
      //  -- a0 : the number of arguments (not including the receiver)
      //  -- a1 : the function to call (checked to be a JSFunction)
      //  -- a2 : the shared function info.
      //  -- cp : the function context.
      // -----------------------------------
  
      if (mode == ConvertReceiverMode::kNullOrUndefined) {
        // Patch receiver to global proxy.
        __ LoadGlobalProxy(a3);
      } else {
        Label convert_to_object, convert_receiver;
        __ Dlsa(at, sp, a0, kPointerSizeLog2);
        __ ld(a3, MemOperand(at));
        __ JumpIfSmi(a3, &convert_to_object);
        STATIC_ASSERT(LAST_JS_RECEIVER_TYPE == LAST_TYPE);
        __ GetObjectType(a3, a4, a4);
        __ Branch(&done_convert, hs, a4, Operand(FIRST_JS_RECEIVER_TYPE));
        if (mode != ConvertReceiverMode::kNotNullOrUndefined) {
          Label convert_global_proxy;
          __ JumpIfRoot(a3, Heap::kUndefinedValueRootIndex,
                        &convert_global_proxy);
          __ JumpIfNotRoot(a3, Heap::kNullValueRootIndex, &convert_to_object);
          __ bind(&convert_global_proxy);
          {
            // Patch receiver to global proxy.
            __ LoadGlobalProxy(a3);
          }
          __ Branch(&convert_receiver);
        }
        __ bind(&convert_to_object);
        {
          // Convert receiver using ToObject.
          // TODO(bmeurer): Inline the allocation here to avoid building the frame
          // in the fast case? (fall back to AllocateInNewSpace?)
          FrameScope scope(masm, StackFrame::INTERNAL);
          __ SmiTag(a0);
          __ Push(a0, a1);
          __ mov(a0, a3);
          __ Push(cp);
          __ Call(masm->isolate()->builtins()->ToObject(),
                  RelocInfo::CODE_TARGET);
          __ Pop(cp);
          __ mov(a3, v0);
          __ Pop(a0, a1);
          __ SmiUntag(a0);
        }
        __ ld(a2, FieldMemOperand(a1, JSFunction::kSharedFunctionInfoOffset));
        __ bind(&convert_receiver);
      }
      __ Dlsa(at, sp, a0, kPointerSizeLog2);
      __ sd(a3, MemOperand(at));
    }
    __ bind(&done_convert);
  
    // ----------- S t a t e -------------
    //  -- a0 : the number of arguments (not including the receiver)
    //  -- a1 : the function to call (checked to be a JSFunction)
    //  -- a2 : the shared function info.
    //  -- cp : the function context.
    // -----------------------------------
  
    if (tail_call_mode == TailCallMode::kAllow) {
      PrepareForTailCall(masm, a0, t0, t1, t2);
    }
  
    __ lw(a2,
          FieldMemOperand(a2, SharedFunctionInfo::kFormalParameterCountOffset));
    ParameterCount actual(a0);
    ParameterCount expected(a2);
    __ InvokeFunctionCode(a1, no_reg, expected, actual, JUMP_FUNCTION,
                          CheckDebugStepCallWrapper());
  
    // The function is a "classConstructor", need to raise an exception.
    __ bind(&class_constructor);
    {
      FrameScope frame(masm, StackFrame::INTERNAL);
      __ Push(a1);
      __ CallRuntime(Runtime::kThrowConstructorNonCallableError);
    }
  }
  
  // static
  void Builtins::Generate_CallBoundFunctionImpl(MacroAssembler* masm,
                                                TailCallMode tail_call_mode) {
    // ----------- S t a t e -------------
    //  -- a0 : the number of arguments (not including the receiver)
    //  -- a1 : the function to call (checked to be a JSBoundFunction)
    // -----------------------------------
    __ AssertBoundFunction(a1);
  
    if (tail_call_mode == TailCallMode::kAllow) {
      PrepareForTailCall(masm, a0, t0, t1, t2);
    }
  
    // Patch the receiver to [[BoundThis]].
    {
      __ ld(at, FieldMemOperand(a1, JSBoundFunction::kBoundThisOffset));
      __ Dlsa(a4, sp, a0, kPointerSizeLog2);
      __ sd(at, MemOperand(a4));
    }
  
    // Load [[BoundArguments]] into a2 and length of that into a4.
    __ ld(a2, FieldMemOperand(a1, JSBoundFunction::kBoundArgumentsOffset));
    __ lw(a4, UntagSmiFieldMemOperand(a2, FixedArray::kLengthOffset));
  
    // ----------- S t a t e -------------
    //  -- a0 : the number of arguments (not including the receiver)
    //  -- a1 : the function to call (checked to be a JSBoundFunction)
    //  -- a2 : the [[BoundArguments]] (implemented as FixedArray)
    //  -- a4 : the number of [[BoundArguments]]
    // -----------------------------------
  
    // Reserve stack space for the [[BoundArguments]].
    {
      Label done;
      __ dsll(a5, a4, kPointerSizeLog2);
      __ Dsubu(sp, sp, Operand(a5));
      // 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".
      __ LoadRoot(at, Heap::kRealStackLimitRootIndex);
      __ Branch(&done, gt, sp, Operand(at));  // Signed comparison.
      // Restore the stack pointer.
      __ Daddu(sp, sp, Operand(a5));
      {
        FrameScope scope(masm, StackFrame::MANUAL);
        __ EnterFrame(StackFrame::INTERNAL);
        __ CallRuntime(Runtime::kThrowStackOverflow);
      }
      __ bind(&done);
    }
  
    // Relocate arguments down the stack.
    {
      Label loop, done_loop;
      __ mov(a5, zero_reg);
      __ bind(&loop);
      __ Branch(&done_loop, gt, a5, Operand(a0));
      __ Dlsa(a6, sp, a4, kPointerSizeLog2);
      __ ld(at, MemOperand(a6));
      __ Dlsa(a6, sp, a5, kPointerSizeLog2);
      __ sd(at, MemOperand(a6));
      __ Daddu(a4, a4, Operand(1));
      __ Daddu(a5, a5, Operand(1));
      __ Branch(&loop);
      __ bind(&done_loop);
    }
  
    // Copy [[BoundArguments]] to the stack (below the arguments).
    {
      Label loop, done_loop;
      __ lw(a4, UntagSmiFieldMemOperand(a2, FixedArray::kLengthOffset));
      __ Daddu(a2, a2, Operand(FixedArray::kHeaderSize - kHeapObjectTag));
      __ bind(&loop);
      __ Dsubu(a4, a4, Operand(1));
      __ Branch(&done_loop, lt, a4, Operand(zero_reg));
      __ Dlsa(a5, a2, a4, kPointerSizeLog2);
      __ ld(at, MemOperand(a5));
      __ Dlsa(a5, sp, a0, kPointerSizeLog2);
      __ sd(at, MemOperand(a5));
      __ Daddu(a0, a0, Operand(1));
      __ Branch(&loop);
      __ bind(&done_loop);
    }
  
    // Call the [[BoundTargetFunction]] via the Call builtin.
    __ ld(a1, FieldMemOperand(a1, JSBoundFunction::kBoundTargetFunctionOffset));
    __ li(at, Operand(ExternalReference(Builtins::kCall_ReceiverIsAny,
                                        masm->isolate())));
    __ ld(at, MemOperand(at));
    __ Daddu(at, at, Operand(Code::kHeaderSize - kHeapObjectTag));
    __ Jump(at);
  }
  
  // static
  void Builtins::Generate_Call(MacroAssembler* masm, ConvertReceiverMode mode,
                               TailCallMode tail_call_mode) {
    // ----------- S t a t e -------------
    //  -- a0 : the number of arguments (not including the receiver)
    //  -- a1 : the target to call (can be any Object).
    // -----------------------------------
  
    Label non_callable, non_function, non_smi;
    __ JumpIfSmi(a1, &non_callable);
    __ bind(&non_smi);
    __ GetObjectType(a1, t1, t2);
    __ Jump(masm->isolate()->builtins()->CallFunction(mode, tail_call_mode),
            RelocInfo::CODE_TARGET, eq, t2, Operand(JS_FUNCTION_TYPE));
    __ Jump(masm->isolate()->builtins()->CallBoundFunction(tail_call_mode),
            RelocInfo::CODE_TARGET, eq, t2, Operand(JS_BOUND_FUNCTION_TYPE));
  
    // Check if target has a [[Call]] internal method.
    __ lbu(t1, FieldMemOperand(t1, Map::kBitFieldOffset));
    __ And(t1, t1, Operand(1 << Map::kIsCallable));
    __ Branch(&non_callable, eq, t1, Operand(zero_reg));
  
    __ Branch(&non_function, ne, t2, Operand(JS_PROXY_TYPE));
  
    // 0. Prepare for tail call if necessary.
    if (tail_call_mode == TailCallMode::kAllow) {
      PrepareForTailCall(masm, a0, t0, t1, t2);
    }
  
    // 1. Runtime fallback for Proxy [[Call]].
    __ Push(a1);
    // Increase the arguments size to include the pushed function and the
    // existing receiver on the stack.
    __ Daddu(a0, a0, 2);
    // Tail-call to the runtime.
    __ JumpToExternalReference(
        ExternalReference(Runtime::kJSProxyCall, masm->isolate()));
  
    // 2. Call to something else, which might have a [[Call]] internal method (if
    // not we raise an exception).
    __ bind(&non_function);
    // Overwrite the original receiver with the (original) target.
    __ Dlsa(at, sp, a0, kPointerSizeLog2);
    __ sd(a1, MemOperand(at));
    // Let the "call_as_function_delegate" take care of the rest.
    __ LoadNativeContextSlot(Context::CALL_AS_FUNCTION_DELEGATE_INDEX, a1);
    __ Jump(masm->isolate()->builtins()->CallFunction(
                ConvertReceiverMode::kNotNullOrUndefined, tail_call_mode),
            RelocInfo::CODE_TARGET);
  
    // 3. Call to something that is not callable.
    __ bind(&non_callable);
    {
      FrameScope scope(masm, StackFrame::INTERNAL);
      __ Push(a1);
      __ CallRuntime(Runtime::kThrowCalledNonCallable);
    }
  }
  
  void Builtins::Generate_ConstructFunction(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- a0 : the number of arguments (not including the receiver)
    //  -- a1 : the constructor to call (checked to be a JSFunction)
    //  -- a3 : the new target (checked to be a constructor)
    // -----------------------------------
    __ AssertFunction(a1);
  
    // Calling convention for function specific ConstructStubs require
    // a2 to contain either an AllocationSite or undefined.
    __ LoadRoot(a2, Heap::kUndefinedValueRootIndex);
  
    // Tail call to the function-specific construct stub (still in the caller
    // context at this point).
    __ ld(a4, FieldMemOperand(a1, JSFunction::kSharedFunctionInfoOffset));
    __ ld(a4, FieldMemOperand(a4, SharedFunctionInfo::kConstructStubOffset));
    __ Daddu(at, a4, Operand(Code::kHeaderSize - kHeapObjectTag));
    __ Jump(at);
  }
  
  // static
  void Builtins::Generate_ConstructBoundFunction(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- a0 : the number of arguments (not including the receiver)
    //  -- a1 : the function to call (checked to be a JSBoundFunction)
    //  -- a3 : the new target (checked to be a constructor)
    // -----------------------------------
    __ AssertBoundFunction(a1);
  
    // Load [[BoundArguments]] into a2 and length of that into a4.
    __ ld(a2, FieldMemOperand(a1, JSBoundFunction::kBoundArgumentsOffset));
    __ lw(a4, UntagSmiFieldMemOperand(a2, FixedArray::kLengthOffset));
  
    // ----------- S t a t e -------------
    //  -- a0 : the number of arguments (not including the receiver)
    //  -- a1 : the function to call (checked to be a JSBoundFunction)
    //  -- a2 : the [[BoundArguments]] (implemented as FixedArray)
    //  -- a3 : the new target (checked to be a constructor)
    //  -- a4 : the number of [[BoundArguments]]
    // -----------------------------------
  
    // Reserve stack space for the [[BoundArguments]].
    {
      Label done;
      __ dsll(a5, a4, kPointerSizeLog2);
      __ Dsubu(sp, sp, Operand(a5));
      // 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".
      __ LoadRoot(at, Heap::kRealStackLimitRootIndex);
      __ Branch(&done, gt, sp, Operand(at));  // Signed comparison.
      // Restore the stack pointer.
      __ Daddu(sp, sp, Operand(a5));
      {
        FrameScope scope(masm, StackFrame::MANUAL);
        __ EnterFrame(StackFrame::INTERNAL);
        __ CallRuntime(Runtime::kThrowStackOverflow);
      }
      __ bind(&done);
    }
  
    // Relocate arguments down the stack.
    {
      Label loop, done_loop;
      __ mov(a5, zero_reg);
      __ bind(&loop);
      __ Branch(&done_loop, ge, a5, Operand(a0));
      __ Dlsa(a6, sp, a4, kPointerSizeLog2);
      __ ld(at, MemOperand(a6));
      __ Dlsa(a6, sp, a5, kPointerSizeLog2);
      __ sd(at, MemOperand(a6));
      __ Daddu(a4, a4, Operand(1));
      __ Daddu(a5, a5, Operand(1));
      __ Branch(&loop);
      __ bind(&done_loop);
    }
  
    // Copy [[BoundArguments]] to the stack (below the arguments).
    {
      Label loop, done_loop;
      __ lw(a4, UntagSmiFieldMemOperand(a2, FixedArray::kLengthOffset));
      __ Daddu(a2, a2, Operand(FixedArray::kHeaderSize - kHeapObjectTag));
      __ bind(&loop);
      __ Dsubu(a4, a4, Operand(1));
      __ Branch(&done_loop, lt, a4, Operand(zero_reg));
      __ Dlsa(a5, a2, a4, kPointerSizeLog2);
      __ ld(at, MemOperand(a5));
      __ Dlsa(a5, sp, a0, kPointerSizeLog2);
      __ sd(at, MemOperand(a5));
      __ Daddu(a0, a0, Operand(1));
      __ Branch(&loop);
      __ bind(&done_loop);
    }
  
    // Patch new.target to [[BoundTargetFunction]] if new.target equals target.
    {
      Label skip_load;
      __ Branch(&skip_load, ne, a1, Operand(a3));
      __ ld(a3, FieldMemOperand(a1, JSBoundFunction::kBoundTargetFunctionOffset));
      __ bind(&skip_load);
    }
  
    // Construct the [[BoundTargetFunction]] via the Construct builtin.
    __ ld(a1, FieldMemOperand(a1, JSBoundFunction::kBoundTargetFunctionOffset));
    __ li(at, Operand(ExternalReference(Builtins::kConstruct, masm->isolate())));
    __ ld(at, MemOperand(at));
    __ Daddu(at, at, Operand(Code::kHeaderSize - kHeapObjectTag));
    __ Jump(at);
  }
  
  // static
  void Builtins::Generate_ConstructProxy(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- a0 : the number of arguments (not including the receiver)
    //  -- a1 : the constructor to call (checked to be a JSProxy)
    //  -- a3 : the new target (either the same as the constructor or
    //          the JSFunction on which new was invoked initially)
    // -----------------------------------
  
    // Call into the Runtime for Proxy [[Construct]].
    __ Push(a1, a3);
    // Include the pushed new_target, constructor and the receiver.
    __ Daddu(a0, a0, Operand(3));
    // Tail-call to the runtime.
    __ JumpToExternalReference(
        ExternalReference(Runtime::kJSProxyConstruct, masm->isolate()));
  }
  
  // static
  void Builtins::Generate_Construct(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- a0 : the number of arguments (not including the receiver)
    //  -- a1 : the constructor to call (can be any Object)
    //  -- a3 : the new target (either the same as the constructor or
    //          the JSFunction on which new was invoked initially)
    // -----------------------------------
  
    // Check if target is a Smi.
    Label non_constructor;
    __ JumpIfSmi(a1, &non_constructor);
  
    // Dispatch based on instance type.
    __ ld(t1, FieldMemOperand(a1, HeapObject::kMapOffset));
    __ lbu(t2, FieldMemOperand(t1, Map::kInstanceTypeOffset));
    __ Jump(masm->isolate()->builtins()->ConstructFunction(),
            RelocInfo::CODE_TARGET, eq, t2, Operand(JS_FUNCTION_TYPE));
  
    // Check if target has a [[Construct]] internal method.
    __ lbu(t3, FieldMemOperand(t1, Map::kBitFieldOffset));
    __ And(t3, t3, Operand(1 << Map::kIsConstructor));
    __ Branch(&non_constructor, eq, t3, Operand(zero_reg));
  
    // Only dispatch to bound functions after checking whether they are
    // constructors.
    __ Jump(masm->isolate()->builtins()->ConstructBoundFunction(),
            RelocInfo::CODE_TARGET, eq, t2, Operand(JS_BOUND_FUNCTION_TYPE));
  
    // Only dispatch to proxies after checking whether they are constructors.
    __ Jump(masm->isolate()->builtins()->ConstructProxy(), RelocInfo::CODE_TARGET,
            eq, t2, Operand(JS_PROXY_TYPE));
  
    // Called Construct on an exotic Object with a [[Construct]] internal method.
    {
      // Overwrite the original receiver with the (original) target.
      __ Dlsa(at, sp, a0, kPointerSizeLog2);
      __ sd(a1, MemOperand(at));
      // Let the "call_as_constructor_delegate" take care of the rest.
      __ LoadNativeContextSlot(Context::CALL_AS_CONSTRUCTOR_DELEGATE_INDEX, a1);
      __ Jump(masm->isolate()->builtins()->CallFunction(),
              RelocInfo::CODE_TARGET);
    }
  
    // Called Construct on an Object that doesn't have a [[Construct]] internal
    // method.
    __ bind(&non_constructor);
    __ Jump(masm->isolate()->builtins()->ConstructedNonConstructable(),
            RelocInfo::CODE_TARGET);
  }
  
  // static
  void Builtins::Generate_AllocateInNewSpace(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- a0 : requested object size (untagged)
    //  -- ra : return address
    // -----------------------------------
    __ SmiTag(a0);
    __ Push(a0);
    __ Move(cp, Smi::kZero);
    __ TailCallRuntime(Runtime::kAllocateInNewSpace);
  }
  
  // static
  void Builtins::Generate_AllocateInOldSpace(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- a0 : requested object size (untagged)
    //  -- ra : return address
    // -----------------------------------
    __ SmiTag(a0);
    __ Move(a1, Smi::FromInt(AllocateTargetSpace::encode(OLD_SPACE)));
    __ Push(a0, a1);
    __ Move(cp, Smi::kZero);
    __ TailCallRuntime(Runtime::kAllocateInTargetSpace);
  }
  
  // static
  void Builtins::Generate_Abort(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- a0 : message_id as Smi
    //  -- ra : return address
    // -----------------------------------
    __ Push(a0);
    __ Move(cp, Smi::kZero);
    __ TailCallRuntime(Runtime::kAbort);
  }
  
  void Builtins::Generate_ArgumentsAdaptorTrampoline(MacroAssembler* masm) {
    // State setup as expected by MacroAssembler::InvokePrologue.
    // ----------- S t a t e -------------
    //  -- a0: actual arguments count
    //  -- a1: function (passed through to callee)
    //  -- a2: expected arguments count
    //  -- a3: new target (passed through to callee)
    // -----------------------------------
  
    Label invoke, dont_adapt_arguments, stack_overflow;
  
    Label enough, too_few;
    __ Branch(&dont_adapt_arguments, eq, a2,
              Operand(SharedFunctionInfo::kDontAdaptArgumentsSentinel));
    // We use Uless as the number of argument should always be greater than 0.
    __ Branch(&too_few, Uless, a0, Operand(a2));
  
    {  // Enough parameters: actual >= expected.
      // a0: actual number of arguments as a smi
      // a1: function
      // a2: expected number of arguments
      // a3: new target (passed through to callee)
      __ bind(&enough);
      EnterArgumentsAdaptorFrame(masm);
      Generate_StackOverflowCheck(masm, a2, a5, at, &stack_overflow);
  
      // Calculate copy start address into a0 and copy end address into a4.
      __ SmiScale(a0, a0, kPointerSizeLog2);
      __ Daddu(a0, fp, a0);
      // Adjust for return address and receiver.
      __ Daddu(a0, a0, Operand(2 * kPointerSize));
      // Compute copy end address.
      __ dsll(a4, a2, kPointerSizeLog2);
      __ dsubu(a4, a0, a4);
  
      // Copy the arguments (including the receiver) to the new stack frame.
      // a0: copy start address
      // a1: function
      // a2: expected number of arguments
      // a3: new target (passed through to callee)
      // a4: copy end address
  
      Label copy;
      __ bind(&copy);
      __ ld(a5, MemOperand(a0));
      __ push(a5);
      __ Branch(USE_DELAY_SLOT, &copy, ne, a0, Operand(a4));
      __ daddiu(a0, a0, -kPointerSize);  // In delay slot.
  
      __ jmp(&invoke);
    }
  
    {  // Too few parameters: Actual < expected.
      __ bind(&too_few);
      EnterArgumentsAdaptorFrame(masm);
      Generate_StackOverflowCheck(masm, a2, a5, at, &stack_overflow);
  
      // Calculate copy start address into a0 and copy end address into a7.
      // a0: actual number of arguments as a smi
      // a1: function
      // a2: expected number of arguments
      // a3: new target (passed through to callee)
      __ SmiScale(a0, a0, kPointerSizeLog2);
      __ Daddu(a0, fp, a0);
      // Adjust for return address and receiver.
      __ Daddu(a0, a0, Operand(2 * kPointerSize));
      // Compute copy end address. Also adjust for return address.
      __ Daddu(a7, fp, kPointerSize);
  
      // Copy the arguments (including the receiver) to the new stack frame.
      // a0: copy start address
      // a1: function
      // a2: expected number of arguments
      // a3: new target (passed through to callee)
      // a7: copy end address
      Label copy;
      __ bind(&copy);
      __ ld(a4, MemOperand(a0));  // Adjusted above for return addr and receiver.
      __ Dsubu(sp, sp, kPointerSize);
      __ Dsubu(a0, a0, kPointerSize);
      __ Branch(USE_DELAY_SLOT, &copy, ne, a0, Operand(a7));
      __ sd(a4, MemOperand(sp));  // In the delay slot.
  
      // Fill the remaining expected arguments with undefined.
      // a1: function
      // a2: expected number of arguments
      // a3: new target (passed through to callee)
      __ LoadRoot(a5, Heap::kUndefinedValueRootIndex);
      __ dsll(a6, a2, kPointerSizeLog2);
      __ Dsubu(a4, fp, Operand(a6));
      // Adjust for frame.
      __ Dsubu(a4, a4, Operand(StandardFrameConstants::kFixedFrameSizeFromFp +
                               2 * kPointerSize));
  
      Label fill;
      __ bind(&fill);
      __ Dsubu(sp, sp, kPointerSize);
      __ Branch(USE_DELAY_SLOT, &fill, ne, sp, Operand(a4));
      __ sd(a5, MemOperand(sp));
    }
  
    // Call the entry point.
    __ bind(&invoke);
    __ mov(a0, a2);
    // a0 : expected number of arguments
    // a1 : function (passed through to callee)
    // a3: new target (passed through to callee)
    __ ld(a4, FieldMemOperand(a1, JSFunction::kCodeEntryOffset));
    __ Call(a4);
  
    // Store offset of return address for deoptimizer.
    masm->isolate()->heap()->SetArgumentsAdaptorDeoptPCOffset(masm->pc_offset());
  
    // Exit frame and return.
    LeaveArgumentsAdaptorFrame(masm);
    __ Ret();
  
    // -------------------------------------------
    // Don't adapt arguments.
    // -------------------------------------------
    __ bind(&dont_adapt_arguments);
    __ ld(a4, FieldMemOperand(a1, JSFunction::kCodeEntryOffset));
    __ Jump(a4);
  
    __ bind(&stack_overflow);
    {
      FrameScope frame(masm, StackFrame::MANUAL);
      __ CallRuntime(Runtime::kThrowStackOverflow);
      __ break_(0xCC);
    }
  }
  
  #undef __
  
  }  // namespace internal
  }  // namespace v8
  
  #endif  // V8_TARGET_ARCH_MIPS64
  