text: // Copyright 2014 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_PPC
  
  #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 -------------
    //  -- r3                 : number of arguments excluding receiver
    //  -- r4                 : target
    //  -- r6                 : new.target
    //  -- sp[0]              : last argument
    //  -- ...
    //  -- sp[4 * (argc - 1)] : first argument
    //  -- sp[4 * argc]       : receiver
    // -----------------------------------
    __ AssertFunction(r4);
  
    // 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).
    __ LoadP(cp, FieldMemOperand(r4, JSFunction::kContextOffset));
  
    // JumpToExternalReference expects r3 to contain the number of arguments
    // including the receiver and the extra arguments.
    const int num_extra_args = 3;
    __ addi(r3, r3, Operand(num_extra_args + 1));
  
    // Insert extra arguments.
    __ SmiTag(r3);
    __ Push(r3, r4, r6);
    __ SmiUntag(r3);
  
    __ JumpToExternalReference(ExternalReference(address, masm->isolate()),
                               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 current 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 current native context.
    __ LoadNativeContextSlot(Context::ARRAY_FUNCTION_INDEX, result);
  }
  
  void Builtins::Generate_InternalArrayCode(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- r3     : number of arguments
    //  -- lr     : return address
    //  -- sp[...]: constructor arguments
    // -----------------------------------
    Label generic_array_code, one_or_more_arguments, two_or_more_arguments;
  
    // Get the InternalArray function.
    GenerateLoadInternalArrayFunction(masm, r4);
  
    if (FLAG_debug_code) {
      // Initial map for the builtin InternalArray functions should be maps.
      __ LoadP(r5, FieldMemOperand(r4, JSFunction::kPrototypeOrInitialMapOffset));
      __ TestIfSmi(r5, r0);
      __ Assert(ne, kUnexpectedInitialMapForInternalArrayFunction, cr0);
      __ CompareObjectType(r5, r6, r7, MAP_TYPE);
      __ Assert(eq, kUnexpectedInitialMapForInternalArrayFunction);
    }
  
    // 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 -------------
    //  -- r3     : number of arguments
    //  -- lr     : return address
    //  -- sp[...]: constructor arguments
    // -----------------------------------
    Label generic_array_code, one_or_more_arguments, two_or_more_arguments;
  
    // Get the Array function.
    GenerateLoadArrayFunction(masm, r4);
  
    if (FLAG_debug_code) {
      // Initial map for the builtin Array functions should be maps.
      __ LoadP(r5, FieldMemOperand(r4, JSFunction::kPrototypeOrInitialMapOffset));
      __ TestIfSmi(r5, r0);
      __ Assert(ne, kUnexpectedInitialMapForArrayFunction, cr0);
      __ CompareObjectType(r5, r6, r7, MAP_TYPE);
      __ Assert(eq, kUnexpectedInitialMapForArrayFunction);
    }
  
    __ mr(r6, r4);
    // Run the native code for the Array function called as a normal function.
    // tail call a stub
    __ LoadRoot(r5, Heap::kUndefinedValueRootIndex);
    ArrayConstructorStub stub(masm->isolate());
    __ TailCallStub(&stub);
  }
  
  // static
  void Builtins::Generate_MathMaxMin(MacroAssembler* masm, MathMaxMinKind kind) {
    // ----------- S t a t e -------------
    //  -- r3                     : number of arguments
    //  -- r4                     : function
    //  -- cp                     : context
    //  -- lr                     : return address
    //  -- sp[(argc - n - 1) * 4] : arg[n] (zero based)
    //  -- sp[argc * 4]           : receiver
    // -----------------------------------
    Condition const cond_done = (kind == MathMaxMinKind::kMin) ? lt : gt;
    Heap::RootListIndex const root_index =
        (kind == MathMaxMinKind::kMin) ? Heap::kInfinityValueRootIndex
                                       : Heap::kMinusInfinityValueRootIndex;
    DoubleRegister const reg = (kind == MathMaxMinKind::kMin) ? d2 : d1;
  
    // Load the accumulator with the default return value (either -Infinity or
    // +Infinity), with the tagged value in r8 and the double value in d1.
    __ LoadRoot(r8, root_index);
    __ lfd(d1, FieldMemOperand(r8, HeapNumber::kValueOffset));
  
    // Setup state for loop
    // r5: address of arg[0] + kPointerSize
    // r6: number of slots to drop at exit (arguments + receiver)
    __ addi(r7, r3, Operand(1));
  
    Label done_loop, loop;
    __ mr(r7, r3);
    __ bind(&loop);
    {
      // Check if all parameters done.
      __ subi(r7, r7, Operand(1));
      __ cmpi(r7, Operand::Zero());
      __ blt(&done_loop);
  
      // Load the next parameter tagged value into r5.
      __ ShiftLeftImm(r5, r7, Operand(kPointerSizeLog2));
      __ LoadPX(r5, MemOperand(sp, r5));
  
      // Load the double value of the parameter into d2, 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(r5, &convert_smi);
      __ LoadP(r6, FieldMemOperand(r5, HeapObject::kMapOffset));
      __ JumpIfRoot(r6, Heap::kHeapNumberMapRootIndex, &convert_number);
      {
        // Parameter is not a Number, use the ToNumber builtin to convert it.
        FrameScope scope(masm, StackFrame::MANUAL);
        __ SmiTag(r3);
        __ SmiTag(r7);
        __ EnterBuiltinFrame(cp, r4, r3);
        __ Push(r7, r8);
        __ mr(r3, r5);
        __ Call(masm->isolate()->builtins()->ToNumber(), RelocInfo::CODE_TARGET);
        __ mr(r5, r3);
        __ Pop(r7, r8);
        __ LeaveBuiltinFrame(cp, r4, r3);
        __ SmiUntag(r7);
        __ SmiUntag(r3);
        {
          // Restore the double accumulator value (d1).
          Label done_restore;
          __ SmiToDouble(d1, r8);
          __ JumpIfSmi(r8, &done_restore);
          __ lfd(d1, FieldMemOperand(r8, HeapNumber::kValueOffset));
          __ bind(&done_restore);
        }
      }
      __ b(&convert);
      __ bind(&convert_number);
      __ lfd(d2, FieldMemOperand(r5, HeapNumber::kValueOffset));
      __ b(&done_convert);
      __ bind(&convert_smi);
      __ SmiToDouble(d2, r5);
      __ bind(&done_convert);
  
      // Perform the actual comparison with the accumulator value on the left hand
      // side (d1) and the next parameter value on the right hand side (d2).
      Label compare_nan, compare_swap;
      __ fcmpu(d1, d2);
      __ bunordered(&compare_nan);
      __ b(cond_done, &loop);
      __ b(CommuteCondition(cond_done), &compare_swap);
  
      // Left and right hand side are equal, check for -0 vs. +0.
      __ TestDoubleIsMinusZero(reg, r9, r0);
      __ bne(&loop);
  
      // Update accumulator. Result is on the right hand side.
      __ bind(&compare_swap);
      __ fmr(d1, d2);
      __ mr(r8, r5);
      __ b(&loop);
  
      // At least one side is NaN, which means that the result will be NaN too.
      // We still need to visit the rest of the arguments.
      __ bind(&compare_nan);
      __ LoadRoot(r8, Heap::kNanValueRootIndex);
      __ lfd(d1, FieldMemOperand(r8, HeapNumber::kValueOffset));
      __ b(&loop);
    }
  
    __ bind(&done_loop);
    // Drop all slots, including the receiver.
    __ addi(r3, r3, Operand(1));
    __ Drop(r3);
    __ mr(r3, r8);
    __ Ret();
  }
  
  // static
  void Builtins::Generate_NumberConstructor(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- r3                     : number of arguments
    //  -- r4                     : constructor function
    //  -- cp                     : context
    //  -- lr                     : return address
    //  -- sp[(argc - n - 1) * 4] : arg[n] (zero based)
    //  -- sp[argc * 4]           : receiver
    // -----------------------------------
  
    // 1. Load the first argument into r3.
    Label no_arguments;
    {
      __ mr(r5, r3);  // Store argc in r5.
      __ cmpi(r3, Operand::Zero());
      __ beq(&no_arguments);
      __ subi(r3, r3, Operand(1));
      __ ShiftLeftImm(r3, r3, Operand(kPointerSizeLog2));
      __ LoadPX(r3, MemOperand(sp, r3));
    }
  
    // 2a. Convert the first argument to a number.
    {
      FrameScope scope(masm, StackFrame::MANUAL);
      __ SmiTag(r5);
      __ EnterBuiltinFrame(cp, r4, r5);
      __ Call(masm->isolate()->builtins()->ToNumber(), RelocInfo::CODE_TARGET);
      __ LeaveBuiltinFrame(cp, r4, r5);
      __ SmiUntag(r5);
    }
  
    {
      // Drop all arguments including the receiver.
      __ Drop(r5);
      __ Ret(1);
    }
  
    // 2b. No arguments, return +0.
    __ bind(&no_arguments);
    __ LoadSmiLiteral(r3, Smi::kZero);
    __ Ret(1);
  }
  
  // static
  void Builtins::Generate_NumberConstructor_ConstructStub(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- r3                     : number of arguments
    //  -- r4                     : constructor function
    //  -- r6                     : new target
    //  -- cp                     : context
    //  -- lr                     : return address
    //  -- sp[(argc - n - 1) * 4] : arg[n] (zero based)
    //  -- sp[argc * 4]           : receiver
    // -----------------------------------
  
    // 1. Make sure we operate in the context of the called function.
    __ LoadP(cp, FieldMemOperand(r4, JSFunction::kContextOffset));
  
    // 2. Load the first argument into r5.
    {
      Label no_arguments, done;
      __ mr(r9, r3);  // Store argc in r9.
      __ cmpi(r3, Operand::Zero());
      __ beq(&no_arguments);
      __ subi(r3, r3, Operand(1));
      __ ShiftLeftImm(r5, r3, Operand(kPointerSizeLog2));
      __ LoadPX(r5, MemOperand(sp, r5));
      __ b(&done);
      __ bind(&no_arguments);
      __ LoadSmiLiteral(r5, Smi::kZero);
      __ bind(&done);
    }
  
    // 3. Make sure r5 is a number.
    {
      Label done_convert;
      __ JumpIfSmi(r5, &done_convert);
      __ CompareObjectType(r5, r7, r7, HEAP_NUMBER_TYPE);
      __ beq(&done_convert);
      {
        FrameScope scope(masm, StackFrame::MANUAL);
        __ SmiTag(r9);
        __ EnterBuiltinFrame(cp, r4, r9);
        __ Push(r6);
        __ mr(r3, r5);
        __ Call(masm->isolate()->builtins()->ToNumber(), RelocInfo::CODE_TARGET);
        __ mr(r5, r3);
        __ Pop(r6);
        __ LeaveBuiltinFrame(cp, r4, r9);
        __ SmiUntag(r9);
      }
      __ bind(&done_convert);
    }
  
    // 4. Check if new target and constructor differ.
    Label drop_frame_and_ret, new_object;
    __ cmp(r4, r6);
    __ bne(&new_object);
  
    // 5. Allocate a JSValue wrapper for the number.
    __ AllocateJSValue(r3, r4, r5, r7, r8, &new_object);
    __ b(&drop_frame_and_ret);
  
    // 6. Fallback to the runtime to create new object.
    __ bind(&new_object);
    {
      FrameScope scope(masm, StackFrame::MANUAL);
      __ SmiTag(r9);
      __ EnterBuiltinFrame(cp, r4, r9);
      __ Push(r5);  // first argument
      FastNewObjectStub stub(masm->isolate());
      __ CallStub(&stub);
      __ Pop(r5);
      __ LeaveBuiltinFrame(cp, r4, r9);
      __ SmiUntag(r9);
    }
    __ StoreP(r5, FieldMemOperand(r3, JSValue::kValueOffset), r0);
  
    __ bind(&drop_frame_and_ret);
    {
      __ Drop(r9);
      __ Ret(1);
    }
  }
  
  // static
  void Builtins::Generate_StringConstructor(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- r3                     : number of arguments
    //  -- r4                     : constructor function
    //  -- cp                     : context
    //  -- lr                     : return address
    //  -- sp[(argc - n - 1) * 4] : arg[n] (zero based)
    //  -- sp[argc * 4]           : receiver
    // -----------------------------------
  
    // 1. Load the first argument into r3.
    Label no_arguments;
    {
      __ mr(r5, r3);  // Store argc in r5.
      __ cmpi(r3, Operand::Zero());
      __ beq(&no_arguments);
      __ subi(r3, r3, Operand(1));
      __ ShiftLeftImm(r3, r3, Operand(kPointerSizeLog2));
      __ LoadPX(r3, MemOperand(sp, r3));
    }
  
    // 2a. At least one argument, return r3 if it's a string, otherwise
    // dispatch to appropriate conversion.
    Label drop_frame_and_ret, to_string, symbol_descriptive_string;
    {
      __ JumpIfSmi(r3, &to_string);
      STATIC_ASSERT(FIRST_NONSTRING_TYPE == SYMBOL_TYPE);
      __ CompareObjectType(r3, r6, r6, FIRST_NONSTRING_TYPE);
      __ bgt(&to_string);
      __ beq(&symbol_descriptive_string);
      __ b(&drop_frame_and_ret);
    }
  
    // 2b. No arguments, return the empty string (and pop the receiver).
    __ bind(&no_arguments);
    {
      __ LoadRoot(r3, Heap::kempty_stringRootIndex);
      __ Ret(1);
    }
  
    // 3a. Convert r3 to a string.
    __ bind(&to_string);
    {
      FrameScope scope(masm, StackFrame::MANUAL);
      __ SmiTag(r5);
      __ EnterBuiltinFrame(cp, r4, r5);
      __ Call(masm->isolate()->builtins()->ToString(), RelocInfo::CODE_TARGET);
      __ LeaveBuiltinFrame(cp, r4, r5);
      __ SmiUntag(r5);
    }
    __ b(&drop_frame_and_ret);
  
    // 3b. Convert symbol in r3 to a string.
    __ bind(&symbol_descriptive_string);
    {
      __ Drop(r5);
      __ Drop(1);
      __ Push(r3);
      __ TailCallRuntime(Runtime::kSymbolDescriptiveString);
    }
  
    __ bind(&drop_frame_and_ret);
    {
      __ Drop(r5);
      __ Ret(1);
    }
  }
  
  // static
  void Builtins::Generate_StringConstructor_ConstructStub(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- r3                     : number of arguments
    //  -- r4                     : constructor function
    //  -- r6                     : new target
    //  -- cp                     : context
    //  -- lr                     : return address
    //  -- sp[(argc - n - 1) * 4] : arg[n] (zero based)
    //  -- sp[argc * 4]           : receiver
    // -----------------------------------
  
    // 1. Make sure we operate in the context of the called function.
    __ LoadP(cp, FieldMemOperand(r4, JSFunction::kContextOffset));
  
    // 2. Load the first argument into r5.
    {
      Label no_arguments, done;
      __ mr(r9, r3);  // Store argc in r9.
      __ cmpi(r3, Operand::Zero());
      __ beq(&no_arguments);
      __ subi(r3, r3, Operand(1));
      __ ShiftLeftImm(r5, r3, Operand(kPointerSizeLog2));
      __ LoadPX(r5, MemOperand(sp, r5));
      __ b(&done);
      __ bind(&no_arguments);
      __ LoadRoot(r5, Heap::kempty_stringRootIndex);
      __ bind(&done);
    }
  
    // 3. Make sure r5 is a string.
    {
      Label convert, done_convert;
      __ JumpIfSmi(r5, &convert);
      __ CompareObjectType(r5, r7, r7, FIRST_NONSTRING_TYPE);
      __ blt(&done_convert);
      __ bind(&convert);
      {
        FrameScope scope(masm, StackFrame::MANUAL);
        __ SmiTag(r9);
        __ EnterBuiltinFrame(cp, r4, r9);
        __ Push(r6);
        __ mr(r3, r5);
        __ Call(masm->isolate()->builtins()->ToString(), RelocInfo::CODE_TARGET);
        __ mr(r5, r3);
        __ Pop(r6);
        __ LeaveBuiltinFrame(cp, r4, r9);
        __ SmiUntag(r9);
      }
      __ bind(&done_convert);
    }
  
    // 4. Check if new target and constructor differ.
    Label drop_frame_and_ret, new_object;
    __ cmp(r4, r6);
    __ bne(&new_object);
  
    // 5. Allocate a JSValue wrapper for the string.
    __ AllocateJSValue(r3, r4, r5, r7, r8, &new_object);
    __ b(&drop_frame_and_ret);
  
    // 6. Fallback to the runtime to create new object.
    __ bind(&new_object);
    {
      FrameScope scope(masm, StackFrame::MANUAL);
      __ SmiTag(r9);
      __ EnterBuiltinFrame(cp, r4, r9);
      __ Push(r5);  // first argument
      FastNewObjectStub stub(masm->isolate());
      __ CallStub(&stub);
      __ Pop(r5);
      __ LeaveBuiltinFrame(cp, r4, r9);
      __ SmiUntag(r9);
    }
    __ StoreP(r5, FieldMemOperand(r3, JSValue::kValueOffset), r0);
  
    __ bind(&drop_frame_and_ret);
    {
      __ Drop(r9);
      __ Ret(1);
    }
  }
  
  static void GenerateTailCallToSharedCode(MacroAssembler* masm) {
    __ LoadP(ip, FieldMemOperand(r4, JSFunction::kSharedFunctionInfoOffset));
    __ LoadP(ip, FieldMemOperand(ip, SharedFunctionInfo::kCodeOffset));
    __ addi(ip, ip, Operand(Code::kHeaderSize - kHeapObjectTag));
    __ JumpToJSEntry(ip);
  }
  
  static void GenerateTailCallToReturnedCode(MacroAssembler* masm,
                                             Runtime::FunctionId function_id) {
    // ----------- S t a t e -------------
    //  -- r3 : argument count (preserved for callee)
    //  -- r4 : target function (preserved for callee)
    //  -- r6 : new target (preserved for callee)
    // -----------------------------------
    {
      FrameAndConstantPoolScope scope(masm, StackFrame::INTERNAL);
      // Push the number of arguments to the callee.
      // Push a copy of the target function and the new target.
      // Push function as parameter to the runtime call.
      __ SmiTag(r3);
      __ Push(r3, r4, r6, r4);
  
      __ CallRuntime(function_id, 1);
      __ mr(r5, r3);
  
      // Restore target function and new target.
      __ Pop(r3, r4, r6);
      __ SmiUntag(r3);
    }
    __ addi(ip, r5, Operand(Code::kHeaderSize - kHeapObjectTag));
    __ JumpToJSEntry(ip);
  }
  
  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(ip, Heap::kStackLimitRootIndex);
    __ cmpl(sp, ip);
    __ bge(&ok);
  
    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 -------------
    //  -- r3     : number of arguments
    //  -- r4     : constructor function
    //  -- r6     : new target
    //  -- cp     : context
    //  -- lr     : return address
    //  -- sp[...]: constructor arguments
    // -----------------------------------
  
    Isolate* isolate = masm->isolate();
  
    // Enter a construct frame.
    {
      FrameAndConstantPoolScope scope(masm, StackFrame::CONSTRUCT);
  
      // Preserve the incoming parameters on the stack.
  
      if (!create_implicit_receiver) {
        __ SmiTag(r7, r3, SetRC);
        __ Push(cp, r7);
        __ PushRoot(Heap::kTheHoleValueRootIndex);
      } else {
        __ SmiTag(r3);
        __ Push(cp, r3);
  
        // Allocate the new receiver object.
        __ Push(r4, r6);
        FastNewObjectStub stub(masm->isolate());
        __ CallStub(&stub);
        __ mr(r7, r3);
        __ Pop(r4, r6);
  
        // ----------- S t a t e -------------
        //  -- r4: constructor function
        //  -- r6: new target
        //  -- r7: newly allocated object
        // -----------------------------------
  
        // Retrieve smi-tagged arguments count from the stack.
        __ LoadP(r3, MemOperand(sp));
        __ SmiUntag(r3, SetRC);
  
        // 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(r7, r7);
      }
  
      // Set up pointer to last argument.
      __ addi(r5, fp, Operand(StandardFrameConstants::kCallerSPOffset));
  
      // Copy arguments and receiver to the expression stack.
      // r3: number of arguments
      // r4: constructor function
      // r5: address of last argument (caller sp)
      // r6: new target
      // cr0: condition indicating whether r3 is zero
      // sp[0]: receiver
      // sp[1]: receiver
      // sp[2]: number of arguments (smi-tagged)
      Label loop, no_args;
      __ beq(&no_args, cr0);
      __ ShiftLeftImm(ip, r3, Operand(kPointerSizeLog2));
      __ sub(sp, sp, ip);
      __ mtctr(r3);
      __ bind(&loop);
      __ subi(ip, ip, Operand(kPointerSize));
      __ LoadPX(r0, MemOperand(r5, ip));
      __ StorePX(r0, MemOperand(sp, ip));
      __ bdnz(&loop);
      __ bind(&no_args);
  
      // Call the function.
      // r3: number of arguments
      // r4: constructor function
      // r6: new target
  
      ParameterCount actual(r3);
      __ InvokeFunction(r4, r6, 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.
      // r3: result
      // sp[0]: receiver
      // sp[1]: number of arguments (smi-tagged)
      __ LoadP(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.
        // r3: result
        // sp[0]: receiver
        // sp[1]: number of arguments (smi-tagged)
        __ JumpIfSmi(r3, &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.
        __ CompareObjectType(r3, r4, r6, FIRST_JS_RECEIVER_TYPE);
        __ bge(&exit);
  
        // Throw away the result of the constructor invocation and use the
        // on-stack receiver as the result.
        __ bind(&use_receiver);
        __ LoadP(r3, MemOperand(sp));
  
        // Remove receiver from the stack, remove caller arguments, and
        // return.
        __ bind(&exit);
        // r3: result
        // sp[0]: receiver (newly allocated object)
        // sp[1]: number of arguments (smi-tagged)
        __ LoadP(r4, MemOperand(sp, 1 * kPointerSize));
      } else {
        __ LoadP(r4, 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(r3, &dont_throw);
      {
        FrameAndConstantPoolScope scope(masm, StackFrame::INTERNAL);
        __ CallRuntime(Runtime::kThrowDerivedConstructorReturnedNonObject);
      }
      __ bind(&dont_throw);
    }
  
    __ SmiToPtrArrayOffset(r4, r4);
    __ add(sp, sp, r4);
    __ addi(sp, sp, Operand(kPointerSize));
    if (create_implicit_receiver) {
      __ IncrementCounter(isolate->counters()->constructed_objects(), 1, r4, r5);
    }
    __ blr();
  }
  
  }  // 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 -------------
    //  -- r3 : the value to pass to the generator
    //  -- r4 : the JSGeneratorObject to resume
    //  -- r5 : the resume mode (tagged)
    //  -- lr : return address
    // -----------------------------------
    __ AssertGeneratorObject(r4);
  
    // Store input value into generator object.
    __ StoreP(r3, FieldMemOperand(r4, JSGeneratorObject::kInputOrDebugPosOffset),
              r0);
    __ RecordWriteField(r4, JSGeneratorObject::kInputOrDebugPosOffset, r3, r6,
                        kLRHasNotBeenSaved, kDontSaveFPRegs);
  
    // Store resume mode into generator object.
    __ StoreP(r5, FieldMemOperand(r4, JSGeneratorObject::kResumeModeOffset), r0);
  
    // Load suspended function and context.
    __ LoadP(cp, FieldMemOperand(r4, JSGeneratorObject::kContextOffset));
    __ LoadP(r7, FieldMemOperand(r4, 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);
    __ mov(ip, Operand(last_step_action));
    __ LoadByte(ip, MemOperand(ip), r0);
    __ extsb(ip, ip);
    __ cmpi(ip, Operand(StepIn));
    __ bge(&prepare_step_in_if_stepping);
  
    // Flood function if we need to continue stepping in the suspended generator.
  
    ExternalReference debug_suspended_generator =
        ExternalReference::debug_suspended_generator_address(masm->isolate());
  
    __ mov(ip, Operand(debug_suspended_generator));
    __ LoadP(ip, MemOperand(ip));
    __ cmp(ip, r4);
    __ beq(&prepare_step_in_suspended_generator);
    __ bind(&stepping_prepared);
  
    // Push receiver.
    __ LoadP(ip, FieldMemOperand(r4, JSGeneratorObject::kReceiverOffset));
    __ Push(ip);
  
    // ----------- S t a t e -------------
    //  -- r4    : the JSGeneratorObject to resume
    //  -- r5    : the resume mode (tagged)
    //  -- r7    : generator function
    //  -- cp    : generator context
    //  -- lr    : 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.
    __ LoadP(r6, FieldMemOperand(r7, JSFunction::kSharedFunctionInfoOffset));
    __ LoadWordArith(
        r3, FieldMemOperand(r6, SharedFunctionInfo::kFormalParameterCountOffset));
    {
      Label loop, done_loop;
      __ LoadRoot(ip, Heap::kTheHoleValueRootIndex);
  #if V8_TARGET_ARCH_PPC64
      __ cmpi(r3, Operand::Zero());
      __ beq(&done_loop);
  #else
      __ SmiUntag(r3, SetRC);
      __ beq(&done_loop, cr0);
  #endif
      __ mtctr(r3);
      __ bind(&loop);
      __ push(ip);
      __ bdnz(&loop);
      __ bind(&done_loop);
    }
  
    // Dispatch on the kind of generator object.
    Label old_generator;
    __ LoadP(r6, FieldMemOperand(r6, SharedFunctionInfo::kFunctionDataOffset));
    __ CompareObjectType(r6, r6, r6, BYTECODE_ARRAY_TYPE);
    __ bne(&old_generator);
  
    // New-style (ignition/turbofan) generator object
    {
      // 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.
      __ mr(r6, r4);
      __ mr(r4, r7);
      __ LoadP(ip, FieldMemOperand(r4, JSFunction::kCodeEntryOffset));
      __ JumpToJSEntry(ip);
    }
  
    // Old-style (full-codegen) generator object
    __ bind(&old_generator);
    {
      // Enter a new JavaScript frame, and initialize its slots as they were when
      // the generator was suspended.
      FrameScope scope(masm, StackFrame::MANUAL);
      __ PushStandardFrame(r7);
  
      // Restore the operand stack.
      __ LoadP(r3, FieldMemOperand(r4, JSGeneratorObject::kOperandStackOffset));
      __ LoadP(r6, FieldMemOperand(r3, FixedArray::kLengthOffset));
      __ addi(r3, r3,
              Operand(FixedArray::kHeaderSize - kHeapObjectTag - kPointerSize));
      {
        Label loop, done_loop;
        __ SmiUntag(r6, SetRC);
        __ beq(&done_loop, cr0);
        __ mtctr(r6);
        __ bind(&loop);
        __ LoadPU(ip, MemOperand(r3, kPointerSize));
        __ Push(ip);
        __ bdnz(&loop);
        __ bind(&done_loop);
      }
  
      // Reset operand stack so we don't leak.
      __ LoadRoot(ip, Heap::kEmptyFixedArrayRootIndex);
      __ StoreP(ip, FieldMemOperand(r4, JSGeneratorObject::kOperandStackOffset),
                r0);
  
      // Resume the generator function at the continuation.
      __ LoadP(r6, FieldMemOperand(r7, JSFunction::kSharedFunctionInfoOffset));
      __ LoadP(r6, FieldMemOperand(r6, SharedFunctionInfo::kCodeOffset));
      __ addi(r6, r6, Operand(Code::kHeaderSize - kHeapObjectTag));
      {
        ConstantPoolUnavailableScope constant_pool_unavailable(masm);
        if (FLAG_enable_embedded_constant_pool) {
          __ LoadConstantPoolPointerRegisterFromCodeTargetAddress(r6);
        }
        __ LoadP(r5, FieldMemOperand(r4, JSGeneratorObject::kContinuationOffset));
        __ SmiUntag(r5);
        __ add(r6, r6, r5);
        __ LoadSmiLiteral(r5,
                          Smi::FromInt(JSGeneratorObject::kGeneratorExecuting));
        __ StoreP(r5, FieldMemOperand(r4, JSGeneratorObject::kContinuationOffset),
                  r0);
        __ mr(r3, r4);  // Continuation expects generator object in r3.
        __ Jump(r6);
      }
    }
  
    __ bind(&prepare_step_in_if_stepping);
    {
      FrameAndConstantPoolScope scope(masm, StackFrame::INTERNAL);
      __ Push(r4, r5, r7);
      __ CallRuntime(Runtime::kDebugPrepareStepInIfStepping);
      __ Pop(r4, r5);
      __ LoadP(r7, FieldMemOperand(r4, JSGeneratorObject::kFunctionOffset));
    }
    __ b(&stepping_prepared);
  
    __ bind(&prepare_step_in_suspended_generator);
    {
      FrameAndConstantPoolScope scope(masm, StackFrame::INTERNAL);
      __ Push(r4, r5);
      __ CallRuntime(Runtime::kDebugPrepareStepInSuspendedGenerator);
      __ Pop(r4, r5);
      __ LoadP(r7, FieldMemOperand(r4, JSGeneratorObject::kFunctionOffset));
    }
    __ b(&stepping_prepared);
  }
  
  void Builtins::Generate_ConstructedNonConstructable(MacroAssembler* masm) {
    FrameAndConstantPoolScope scope(masm, StackFrame::INTERNAL);
    __ push(r4);
    __ CallRuntime(Runtime::kThrowConstructedNonConstructable);
  }
  
  enum IsTagged { kArgcIsSmiTagged, kArgcIsUntaggedInt };
  
  // Clobbers r5; 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(r5, Heap::kRealStackLimitRootIndex);
    // Make r5 the space we have left. The stack might already be overflowed
    // here which will cause r5 to become negative.
    __ sub(r5, sp, r5);
    // Check if the arguments will overflow the stack.
    if (argc_is_tagged == kArgcIsSmiTagged) {
      __ SmiToPtrArrayOffset(r0, argc);
    } else {
      DCHECK(argc_is_tagged == kArgcIsUntaggedInt);
      __ ShiftLeftImm(r0, argc, Operand(kPointerSizeLog2));
    }
    __ cmp(r5, r0);
    __ bgt(&okay);  // Signed comparison.
  
    // Out of stack space.
    __ CallRuntime(Runtime::kThrowStackOverflow);
  
    __ bind(&okay);
  }
  
  static void Generate_JSEntryTrampolineHelper(MacroAssembler* masm,
                                               bool is_construct) {
    // Called from Generate_JS_Entry
    // r3: new.target
    // r4: function
    // r5: receiver
    // r6: argc
    // r7: argv
    // r0,r8-r9, cp may be clobbered
    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());
      __ mov(cp, Operand(context_address));
      __ LoadP(cp, MemOperand(cp));
  
      __ InitializeRootRegister();
  
      // Push the function and the receiver onto the stack.
      __ Push(r4, r5);
  
      // Check if we have enough stack space to push all arguments.
      // Clobbers r5.
      Generate_CheckStackOverflow(masm, r6, kArgcIsUntaggedInt);
  
      // Copy arguments to the stack in a loop.
      // r4: function
      // r6: argc
      // r7: argv, i.e. points to first arg
      Label loop, entry;
      __ ShiftLeftImm(r0, r6, Operand(kPointerSizeLog2));
      __ add(r5, r7, r0);
      // r5 points past last arg.
      __ b(&entry);
      __ bind(&loop);
      __ LoadP(r8, MemOperand(r7));  // read next parameter
      __ addi(r7, r7, Operand(kPointerSize));
      __ LoadP(r0, MemOperand(r8));  // dereference handle
      __ push(r0);                   // push parameter
      __ bind(&entry);
      __ cmp(r7, r5);
      __ bne(&loop);
  
      // Setup new.target and argc.
      __ mr(r7, r3);
      __ mr(r3, r6);
      __ mr(r6, r7);
  
      // Initialize all JavaScript callee-saved registers, since they will be seen
      // by the garbage collector as part of handlers.
      __ LoadRoot(r7, Heap::kUndefinedValueRootIndex);
      __ mr(r14, r7);
      __ mr(r15, r7);
      __ mr(r16, r7);
      __ mr(r17, r7);
  
      // Invoke the code.
      Handle<Code> builtin = is_construct
                                 ? masm->isolate()->builtins()->Construct()
                                 : masm->isolate()->builtins()->Call();
      __ Call(builtin, RelocInfo::CODE_TARGET);
  
      // Exit the JS frame and remove the parameters (except function), and
      // return.
    }
    __ blr();
  
    // r3: result
  }
  
  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.
    __ LoadP(args_count,
             MemOperand(fp, InterpreterFrameConstants::kBytecodeArrayFromFp));
    __ lwz(args_count,
           FieldMemOperand(args_count, BytecodeArray::kParameterSizeOffset));
  
    // Leave the frame (also dropping the register file).
    __ LeaveFrame(StackFrame::JAVA_SCRIPT);
  
    __ add(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 r4: the JS function object being called.
  //   o r6: the new target
  //   o cp: our context
  //   o pp: the caller's constant pool pointer (if enabled)
  //   o fp: the caller's frame pointer
  //   o sp: stack pointer
  //   o lr: 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(r4);
  
    // Get the bytecode array from the function object (or from the DebugInfo if
    // it is present) and load it into kInterpreterBytecodeArrayRegister.
    __ LoadP(r3, FieldMemOperand(r4, JSFunction::kSharedFunctionInfoOffset));
    Label array_done;
    Register debug_info = r5;
    DCHECK(!debug_info.is(r3));
    __ LoadP(debug_info,
             FieldMemOperand(r3, SharedFunctionInfo::kDebugInfoOffset));
    // Load original bytecode array or the debug copy.
    __ LoadP(kInterpreterBytecodeArrayRegister,
             FieldMemOperand(r3, SharedFunctionInfo::kFunctionDataOffset));
    __ CmpSmiLiteral(debug_info, DebugInfo::uninitialized(), r0);
    __ beq(&array_done);
    __ LoadP(kInterpreterBytecodeArrayRegister,
             FieldMemOperand(debug_info, DebugInfo::kDebugBytecodeArrayIndex));
    __ bind(&array_done);
  
    // Check whether we should continue to use the interpreter.
    Label switch_to_different_code_kind;
    __ LoadP(r3, FieldMemOperand(r3, SharedFunctionInfo::kCodeOffset));
    __ mov(ip, Operand(masm->CodeObject()));  // Self-reference to this code.
    __ cmp(r3, ip);
    __ bne(&switch_to_different_code_kind);
  
    // Increment invocation count for the function.
    __ LoadP(r7, FieldMemOperand(r4, JSFunction::kLiteralsOffset));
    __ LoadP(r7, FieldMemOperand(r7, LiteralsArray::kFeedbackVectorOffset));
    __ LoadP(r8, FieldMemOperand(r7, TypeFeedbackVector::kInvocationCountIndex *
                                             kPointerSize +
                                         TypeFeedbackVector::kHeaderSize));
    __ AddSmiLiteral(r8, r8, Smi::FromInt(1), r0);
    __ StoreP(r8, FieldMemOperand(r7, TypeFeedbackVector::kInvocationCountIndex *
                                              kPointerSize +
                                          TypeFeedbackVector::kHeaderSize),
              r0);
  
    // Check function data field is actually a BytecodeArray object.
  
    if (FLAG_debug_code) {
      __ TestIfSmi(kInterpreterBytecodeArrayRegister, r0);
      __ Assert(ne, kFunctionDataShouldBeBytecodeArrayOnInterpreterEntry);
      __ CompareObjectType(kInterpreterBytecodeArrayRegister, r3, no_reg,
                           BYTECODE_ARRAY_TYPE);
      __ Assert(eq, kFunctionDataShouldBeBytecodeArrayOnInterpreterEntry);
    }
  
    // Load initial bytecode offset.
    __ mov(kInterpreterBytecodeOffsetRegister,
           Operand(BytecodeArray::kHeaderSize - kHeapObjectTag));
  
    // Push new.target, bytecode array and Smi tagged bytecode array offset.
    __ SmiTag(r3, kInterpreterBytecodeOffsetRegister);
    __ Push(r6, kInterpreterBytecodeArrayRegister, r3);
  
    // Allocate the local and temporary register file on the stack.
    {
      // Load frame size (word) from the BytecodeArray object.
      __ lwz(r5, FieldMemOperand(kInterpreterBytecodeArrayRegister,
                                 BytecodeArray::kFrameSizeOffset));
  
      // Do a stack check to ensure we don't go over the limit.
      Label ok;
      __ sub(r6, sp, r5);
      __ LoadRoot(r0, Heap::kRealStackLimitRootIndex);
      __ cmpl(r6, r0);
      __ bge(&ok);
      __ CallRuntime(Runtime::kThrowStackOverflow);
      __ bind(&ok);
  
      // If ok, push undefined as the initial value for all register file entries.
      // TODO(rmcilroy): Consider doing more than one push per loop iteration.
      Label loop, no_args;
      __ LoadRoot(r6, Heap::kUndefinedValueRootIndex);
      __ ShiftRightImm(r5, r5, Operand(kPointerSizeLog2), SetRC);
      __ beq(&no_args, cr0);
      __ mtctr(r5);
      __ bind(&loop);
      __ push(r6);
      __ bdnz(&loop);
      __ bind(&no_args);
    }
  
    // Load accumulator and dispatch table into registers.
    __ LoadRoot(kInterpreterAccumulatorRegister, Heap::kUndefinedValueRootIndex);
    __ mov(kInterpreterDispatchTableRegister,
           Operand(ExternalReference::interpreter_dispatch_table_address(
               masm->isolate())));
  
    // Dispatch to the first bytecode handler for the function.
    __ lbzx(r4, MemOperand(kInterpreterBytecodeArrayRegister,
                           kInterpreterBytecodeOffsetRegister));
    __ ShiftLeftImm(ip, r4, Operand(kPointerSizeLog2));
    __ LoadPX(ip, MemOperand(kInterpreterDispatchTableRegister, ip));
    __ Call(ip);
  
    masm->isolate()->heap()->SetInterpreterEntryReturnPCOffset(masm->pc_offset());
  
    // The return value is in r3.
    LeaveInterpreterFrame(masm, r5);
    __ blr();
  
    // 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);
    __ LoadP(r7, FieldMemOperand(r4, JSFunction::kSharedFunctionInfoOffset));
    __ LoadP(r7, FieldMemOperand(r7, SharedFunctionInfo::kCodeOffset));
    __ addi(r7, r7, Operand(Code::kHeaderSize - kHeapObjectTag));
    __ StoreP(r7, FieldMemOperand(r4, JSFunction::kCodeEntryOffset), r0);
    __ RecordWriteCodeEntryField(r4, r7, r8);
    __ JumpToJSEntry(r7);
  }
  
  static void Generate_StackOverflowCheck(MacroAssembler* masm, Register num_args,
                                          Register scratch,
                                          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(scratch, Heap::kRealStackLimitRootIndex);
    // Make scratch the space we have left. The stack might already be overflowed
    // here which will cause scratch to become negative.
    __ sub(scratch, sp, scratch);
    // Check if the arguments will overflow the stack.
    __ ShiftLeftImm(r0, num_args, Operand(kPointerSizeLog2));
    __ cmp(scratch, r0);
    __ ble(stack_overflow);  // Signed comparison.
  }
  
  static void Generate_InterpreterPushArgs(MacroAssembler* masm,
                                           Register num_args, Register index,
                                           Register count, Register scratch,
                                           Label* stack_overflow) {
    // A stack check before pushing arguments.
    Generate_StackOverflowCheck(masm, num_args, scratch, stack_overflow);
  
    Label loop;
    __ addi(index, index, Operand(kPointerSize));  // Bias up for LoadPU
    __ mtctr(count);
    __ bind(&loop);
    __ LoadPU(scratch, MemOperand(index, -kPointerSize));
    __ push(scratch);
    __ bdnz(&loop);
  }
  
  // static
  void Builtins::Generate_InterpreterPushArgsAndCallImpl(
      MacroAssembler* masm, TailCallMode tail_call_mode,
      CallableType function_type) {
    // ----------- S t a t e -------------
    //  -- r3 : the number of arguments (not including the receiver)
    //  -- r5 : 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.
    //  -- r4 : the target to call (can be any Object).
    // -----------------------------------
    Label stack_overflow;
  
    // Calculate number of arguments (add one for receiver).
    __ addi(r6, r3, Operand(1));
  
    // Push the arguments. r5, r6, r7 will be modified.
    Generate_InterpreterPushArgs(masm, r6, r5, r6, r7, &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.
      __ bkpt(0);
    }
  }
  
  // static
  void Builtins::Generate_InterpreterPushArgsAndConstructImpl(
      MacroAssembler* masm, CallableType construct_type) {
    // ----------- S t a t e -------------
    // -- r3 : argument count (not including receiver)
    // -- r6 : new target
    // -- r4 : constructor to call
    // -- r5 : allocation site feedback if available, undefined otherwise.
    // -- r7 : address of the first argument
    // -----------------------------------
    Label stack_overflow;
  
    // Push a slot for the receiver to be constructed.
    __ li(r0, Operand::Zero());
    __ push(r0);
  
    // Push the arguments (skip if none).
    Label skip;
    __ cmpi(r3, Operand::Zero());
    __ beq(&skip);
    // Push the arguments. r8, r7, r9 will be modified.
    Generate_InterpreterPushArgs(masm, r3, r7, r3, r8, &stack_overflow);
    __ bind(&skip);
  
    __ AssertUndefinedOrAllocationSite(r5, r8);
    if (construct_type == CallableType::kJSFunction) {
      __ AssertFunction(r4);
  
      // Tail call to the function-specific construct stub (still in the caller
      // context at this point).
      __ LoadP(r7, FieldMemOperand(r4, JSFunction::kSharedFunctionInfoOffset));
      __ LoadP(r7, FieldMemOperand(r7, SharedFunctionInfo::kConstructStubOffset));
      // Jump to the construct function.
      __ addi(ip, r7, Operand(Code::kHeaderSize - kHeapObjectTag));
      __ Jump(ip);
  
    } else {
      DCHECK_EQ(construct_type, CallableType::kAny);
      // Call the constructor with r3, r4, and r6 unmodified.
      __ Jump(masm->isolate()->builtins()->Construct(), RelocInfo::CODE_TARGET);
    }
  
    __ bind(&stack_overflow);
    {
      __ TailCallRuntime(Runtime::kThrowStackOverflow);
      // Unreachable Code.
      __ bkpt(0);
    }
  }
  
  // static
  void Builtins::Generate_InterpreterPushArgsAndConstructArray(
      MacroAssembler* masm) {
    // ----------- S t a t e -------------
    // -- r3 : argument count (not including receiver)
    // -- r4 : target to call verified to be Array function
    // -- r5 : allocation site feedback if available, undefined otherwise.
    // -- r6 : address of the first argument
    // -----------------------------------
    Label stack_overflow;
  
    __ addi(r7, r3, Operand(1));  // Add one for receiver.
  
    // Push the arguments. r6, r8, r3 will be modified.
    Generate_InterpreterPushArgs(masm, r7, r6, r7, r8, &stack_overflow);
  
    // Array constructor expects constructor in r6. It is same as r4 here.
    __ mr(r6, r4);
  
    ArrayConstructorStub stub(masm->isolate());
    __ TailCallStub(&stub);
  
    __ bind(&stack_overflow);
    {
      __ TailCallRuntime(Runtime::kThrowStackOverflow);
      // Unreachable code.
      __ bkpt(0);
    }
  }
  
  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);
    __ Move(r5, masm->isolate()->builtins()->InterpreterEntryTrampoline());
    __ addi(r0, r5, Operand(interpreter_entry_return_pc_offset->value() +
                            Code::kHeaderSize - kHeapObjectTag));
    __ mtlr(r0);
  
    // Initialize the dispatch table register.
    __ mov(kInterpreterDispatchTableRegister,
           Operand(ExternalReference::interpreter_dispatch_table_address(
               masm->isolate())));
  
    // Get the bytecode array pointer from the frame.
    __ LoadP(kInterpreterBytecodeArrayRegister,
             MemOperand(fp, InterpreterFrameConstants::kBytecodeArrayFromFp));
  
    if (FLAG_debug_code) {
      // Check function data field is actually a BytecodeArray object.
      __ TestIfSmi(kInterpreterBytecodeArrayRegister, r0);
      __ Assert(ne, kFunctionDataShouldBeBytecodeArrayOnInterpreterEntry);
      __ CompareObjectType(kInterpreterBytecodeArrayRegister, r4, no_reg,
                           BYTECODE_ARRAY_TYPE);
      __ Assert(eq, kFunctionDataShouldBeBytecodeArrayOnInterpreterEntry);
    }
  
    // Get the target bytecode offset from the frame.
    __ LoadP(kInterpreterBytecodeOffsetRegister,
             MemOperand(fp, InterpreterFrameConstants::kBytecodeOffsetFromFp));
    __ SmiUntag(kInterpreterBytecodeOffsetRegister);
  
    // Dispatch to the target bytecode.
    __ lbzx(r4, MemOperand(kInterpreterBytecodeArrayRegister,
                           kInterpreterBytecodeOffsetRegister));
    __ ShiftLeftImm(ip, r4, Operand(kPointerSizeLog2));
    __ LoadPX(ip, MemOperand(kInterpreterDispatchTableRegister, ip));
    __ Jump(ip);
  }
  
  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.
    __ LoadP(r4, MemOperand(fp, InterpreterFrameConstants::kBytecodeArrayFromFp));
    __ LoadP(r5,
             MemOperand(fp, InterpreterFrameConstants::kBytecodeOffsetFromFp));
    __ LoadP(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
    {
      FrameScope scope(masm, StackFrame::INTERNAL);
      __ Push(kInterpreterAccumulatorRegister, r4, r5);
      __ CallRuntime(Runtime::kInterpreterAdvanceBytecodeOffset);
      __ Move(r5, r3);  // Result is the new bytecode offset.
      __ Pop(kInterpreterAccumulatorRegister);
    }
    __ StoreP(r5,
              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 -------------
    //  -- r3 : argument count (preserved for callee)
    //  -- r6 : new target (preserved for callee)
    //  -- r4 : target function (preserved for callee)
    // -----------------------------------
    // First lookup code, maybe we don't need to compile!
    Label gotta_call_runtime;
    Label try_shared;
    Label loop_top, loop_bottom;
  
    Register closure = r4;
    Register map = r9;
    Register index = r5;
    __ LoadP(map,
             FieldMemOperand(closure, JSFunction::kSharedFunctionInfoOffset));
    __ LoadP(map,
             FieldMemOperand(map, SharedFunctionInfo::kOptimizedCodeMapOffset));
    __ LoadP(index, FieldMemOperand(map, FixedArray::kLengthOffset));
    __ CmpSmiLiteral(index, Smi::FromInt(2), r0);
    __ blt(&gotta_call_runtime);
  
    // Find literals.
    // r10 : native context
    // r5  : length / index
    // r9  : optimized code map
    // r6  : new target
    // r4  : closure
    Register native_context = r10;
    __ LoadP(native_context, NativeContextMemOperand());
  
    __ bind(&loop_top);
    Register temp = r11;
    Register array_pointer = r8;
  
    // Does the native context match?
    __ SmiToPtrArrayOffset(array_pointer, index);
    __ add(array_pointer, map, array_pointer);
    __ LoadP(temp, FieldMemOperand(array_pointer,
                                   SharedFunctionInfo::kOffsetToPreviousContext));
    __ LoadP(temp, FieldMemOperand(temp, WeakCell::kValueOffset));
    __ cmp(temp, native_context);
    __ bne(&loop_bottom);
    // OSR id set to none?
    __ LoadP(temp,
             FieldMemOperand(array_pointer,
                             SharedFunctionInfo::kOffsetToPreviousOsrAstId));
    const int bailout_id = BailoutId::None().ToInt();
    __ CmpSmiLiteral(temp, Smi::FromInt(bailout_id), r0);
    __ bne(&loop_bottom);
    // Literals available?
    __ LoadP(temp,
             FieldMemOperand(array_pointer,
                             SharedFunctionInfo::kOffsetToPreviousLiterals));
    __ LoadP(temp, FieldMemOperand(temp, WeakCell::kValueOffset));
    __ JumpIfSmi(temp, &gotta_call_runtime);
  
    // Save the literals in the closure.
    __ StoreP(temp, FieldMemOperand(closure, JSFunction::kLiteralsOffset), r0);
    __ RecordWriteField(closure, JSFunction::kLiteralsOffset, temp, r7,
                        kLRHasNotBeenSaved, kDontSaveFPRegs, EMIT_REMEMBERED_SET,
                        OMIT_SMI_CHECK);
  
    // Code available?
    Register entry = r7;
    __ LoadP(entry,
             FieldMemOperand(array_pointer,
                             SharedFunctionInfo::kOffsetToPreviousCachedCode));
    __ LoadP(entry, FieldMemOperand(entry, WeakCell::kValueOffset));
    __ JumpIfSmi(entry, &try_shared);
  
    // Found literals and code. Get them into the closure and return.
    // Store code entry in the closure.
    __ addi(entry, entry, Operand(Code::kHeaderSize - kHeapObjectTag));
    __ StoreP(entry, FieldMemOperand(closure, JSFunction::kCodeEntryOffset), r0);
    __ RecordWriteCodeEntryField(closure, entry, r8);
  
    // Link the closure into the optimized function list.
    // r7 : code entry
    // r10: native context
    // r4 : closure
    __ LoadP(
        r8, ContextMemOperand(native_context, Context::OPTIMIZED_FUNCTIONS_LIST));
    __ StoreP(r8, FieldMemOperand(closure, JSFunction::kNextFunctionLinkOffset),
              r0);
    __ RecordWriteField(closure, JSFunction::kNextFunctionLinkOffset, r8, temp,
                        kLRHasNotBeenSaved, kDontSaveFPRegs, EMIT_REMEMBERED_SET,
                        OMIT_SMI_CHECK);
    const int function_list_offset =
        Context::SlotOffset(Context::OPTIMIZED_FUNCTIONS_LIST);
    __ StoreP(
        closure,
        ContextMemOperand(native_context, Context::OPTIMIZED_FUNCTIONS_LIST), r0);
    // Save closure before the write barrier.
    __ mr(r8, closure);
    __ RecordWriteContextSlot(native_context, function_list_offset, r8, temp,
                              kLRHasNotBeenSaved, kDontSaveFPRegs);
    __ JumpToJSEntry(entry);
  
    __ bind(&loop_bottom);
    __ SubSmiLiteral(index, index, Smi::FromInt(SharedFunctionInfo::kEntryLength),
                     r0);
    __ CmpSmiLiteral(index, Smi::FromInt(1), r0);
    __ bgt(&loop_top);
  
    // We found neither literals nor code.
    __ b(&gotta_call_runtime);
  
    __ bind(&try_shared);
    __ LoadP(entry,
             FieldMemOperand(closure, JSFunction::kSharedFunctionInfoOffset));
    // Is the shared function marked for tier up?
    __ lbz(r8, FieldMemOperand(entry,
                               SharedFunctionInfo::kMarkedForTierUpByteOffset));
    __ TestBit(r8, SharedFunctionInfo::kMarkedForTierUpBitWithinByte, r0);
    __ bne(&gotta_call_runtime, cr0);
    // Is the full code valid?
    __ LoadP(entry, FieldMemOperand(entry, SharedFunctionInfo::kCodeOffset));
    __ lwz(r8, FieldMemOperand(entry, Code::kFlagsOffset));
    __ DecodeField<Code::KindField>(r8);
    __ cmpi(r8, Operand(Code::BUILTIN));
    __ beq(&gotta_call_runtime);
    // Yes, install the full code.
    __ addi(entry, entry, Operand(Code::kHeaderSize - kHeapObjectTag));
    __ StoreP(entry, FieldMemOperand(closure, JSFunction::kCodeEntryOffset), r0);
    __ RecordWriteCodeEntryField(closure, entry, r8);
    __ JumpToJSEntry(entry);
  
    __ bind(&gotta_call_runtime);
    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 -------------
    //  -- r3 : argument count (preserved for callee)
    //  -- r4 : new target (preserved for callee)
    //  -- r6 : target function (preserved for callee)
    // -----------------------------------
    Label failed;
    {
      FrameScope scope(masm, StackFrame::INTERNAL);
      // Preserve argument count for later compare.
      __ Move(r7, r3);
      // Push a copy of the target function and the new target.
      // Push function as parameter to the runtime call.
      __ SmiTag(r3);
      __ Push(r3, r4, r6, r4);
  
      // Copy arguments from caller (stdlib, foreign, heap).
      Label args_done;
      for (int j = 0; j < 4; ++j) {
        Label over;
        if (j < 3) {
          __ cmpi(r7, Operand(j));
          __ bne(&over);
        }
        for (int i = j - 1; i >= 0; --i) {
          __ LoadP(r7, MemOperand(fp, StandardFrameConstants::kCallerSPOffset +
                                          i * kPointerSize));
          __ push(r7);
        }
        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(r3, &failed);
  
      __ Drop(2);
      __ pop(r7);
      __ SmiUntag(r7);
      scope.GenerateLeaveFrame();
  
      __ addi(r7, r7, Operand(1));
      __ Drop(r7);
      __ Ret();
  
      __ bind(&failed);
      // Restore target function and new target.
      __ Pop(r3, r4, r6);
      __ SmiUntag(r3);
    }
    // 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.
  
    // Point r3 at the start of the PlatformCodeAge sequence.
    __ mr(r3, ip);
  
    // The following registers must be saved and restored when calling through to
    // the runtime:
    //   r3 - contains return address (beginning of patch sequence)
    //   r4 - isolate
    //   r6 - new target
    //   lr - return address
    FrameScope scope(masm, StackFrame::MANUAL);
    __ mflr(r0);
    __ MultiPush(r0.bit() | r3.bit() | r4.bit() | r6.bit() | fp.bit());
    __ PrepareCallCFunction(2, 0, r5);
    __ mov(r4, Operand(ExternalReference::isolate_address(masm->isolate())));
    __ CallCFunction(
        ExternalReference::get_make_code_young_function(masm->isolate()), 2);
    __ MultiPop(r0.bit() | r3.bit() | r4.bit() | r6.bit() | fp.bit());
    __ mtlr(r0);
    __ mr(ip, r3);
    __ Jump(ip);
  }
  
  #define DEFINE_CODE_AGE_BUILTIN_GENERATOR(C)                  \
    void Builtins::Generate_Make##C##CodeYoungAgainEvenMarking( \
        MacroAssembler* masm) {                                 \
      GenerateMakeCodeYoungAgainCommon(masm);                   \
    }                                                           \
    void Builtins::Generate_Make##C##CodeYoungAgainOddMarking(  \
        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, 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.
  
    // Point r3 at the start of the PlatformCodeAge sequence.
    __ mr(r3, ip);
  
    // The following registers must be saved and restored when calling through to
    // the runtime:
    //   r3 - contains return address (beginning of patch sequence)
    //   r4 - isolate
    //   r6 - new target
    //   lr - return address
    FrameScope scope(masm, StackFrame::MANUAL);
    __ mflr(r0);
    __ MultiPush(r0.bit() | r3.bit() | r4.bit() | r6.bit() | fp.bit());
    __ PrepareCallCFunction(2, 0, r5);
    __ mov(r4, Operand(ExternalReference::isolate_address(masm->isolate())));
    __ CallCFunction(
        ExternalReference::get_mark_code_as_executed_function(masm->isolate()),
        2);
    __ MultiPop(r0.bit() | r3.bit() | r4.bit() | r6.bit() | fp.bit());
    __ mtlr(r0);
    __ mr(ip, r3);
  
    // Perform prologue operations usually performed by the young code stub.
    __ PushStandardFrame(r4);
  
    // Jump to point after the code-age stub.
    __ addi(r3, ip, Operand(kNoCodeAgeSequenceLength));
    __ Jump(r3);
  }
  
  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) {
    {
      FrameAndConstantPoolScope 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);
    }
  
    __ addi(sp, sp, Operand(kPointerSize));  // Ignore state
    __ blr();                                // 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) {
    {
      FrameAndConstantPoolScope scope(masm, StackFrame::INTERNAL);
      // Pass the function and deoptimization type to the runtime system.
      __ LoadSmiLiteral(r3, Smi::FromInt(static_cast<int>(type)));
      __ push(r3);
      __ CallRuntime(Runtime::kNotifyDeoptimized);
    }
  
    // Get the full codegen state from the stack and untag it -> r9.
    __ LoadP(r9, MemOperand(sp, 0 * kPointerSize));
    __ SmiUntag(r9);
    // Switch on the state.
    Label with_tos_register, unknown_state;
    __ cmpi(
        r9,
        Operand(static_cast<intptr_t>(Deoptimizer::BailoutState::NO_REGISTERS)));
    __ bne(&with_tos_register);
    __ addi(sp, sp, Operand(1 * kPointerSize));  // Remove state.
    __ Ret();
  
    __ bind(&with_tos_register);
    DCHECK_EQ(kInterpreterAccumulatorRegister.code(), r3.code());
    __ LoadP(r3, MemOperand(sp, 1 * kPointerSize));
    __ cmpi(
        r9,
        Operand(static_cast<intptr_t>(Deoptimizer::BailoutState::TOS_REGISTER)));
    __ bne(&unknown_state);
    __ addi(sp, sp, Operand(2 * kPointerSize));  // Remove state.
    __ Ret();
  
    __ 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 registers {r7, r8, r9, r10}.
  void CompatibleReceiverCheck(MacroAssembler* masm, Register receiver,
                               Register function_template_info,
                               Label* receiver_check_failed) {
    Register signature = r7;
    Register map = r8;
    Register constructor = r9;
    Register scratch = r10;
  
    // If there is no signature, return the holder.
    __ LoadP(signature, FieldMemOperand(function_template_info,
                                        FunctionTemplateInfo::kSignatureOffset));
    Label receiver_check_passed;
    __ JumpIfRoot(signature, Heap::kUndefinedValueRootIndex,
                  &receiver_check_passed);
  
    // Walk the prototype chain.
    __ LoadP(map, FieldMemOperand(receiver, HeapObject::kMapOffset));
    Label prototype_loop_start;
    __ bind(&prototype_loop_start);
  
    // Get the constructor, if any.
    __ GetMapConstructor(constructor, map, scratch, scratch);
    __ cmpi(scratch, Operand(JS_FUNCTION_TYPE));
    Label next_prototype;
    __ bne(&next_prototype);
    Register type = constructor;
    __ LoadP(type,
             FieldMemOperand(constructor, JSFunction::kSharedFunctionInfoOffset));
    __ LoadP(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.
    __ cmp(signature, type);
    __ beq(&receiver_check_passed);
  
    // If the current type is not a FunctionTemplateInfo, load the next prototype
    // in the chain.
    __ JumpIfSmi(type, &next_prototype);
    __ CompareObjectType(type, scratch, scratch, FUNCTION_TEMPLATE_INFO_TYPE);
    __ bne(&next_prototype);
  
    // Otherwise load the parent function template and iterate.
    __ LoadP(type,
             FieldMemOperand(type, FunctionTemplateInfo::kParentTemplateOffset));
    __ b(&function_template_loop);
  
    // Load the next prototype.
    __ bind(&next_prototype);
    __ lwz(scratch, FieldMemOperand(map, Map::kBitField3Offset));
    __ DecodeField<Map::HasHiddenPrototype>(scratch, SetRC);
    __ beq(receiver_check_failed, cr0);
  
    __ LoadP(receiver, FieldMemOperand(map, Map::kPrototypeOffset));
    __ LoadP(map, FieldMemOperand(receiver, HeapObject::kMapOffset));
    // Iterate.
    __ b(&prototype_loop_start);
  
    __ bind(&receiver_check_passed);
  }
  
  void Builtins::Generate_HandleFastApiCall(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- r3                 : number of arguments excluding receiver
    //  -- r4                 : callee
    //  -- lr                 : return address
    //  -- sp[0]              : last argument
    //  -- ...
    //  -- sp[4 * (argc - 1)] : first argument
    //  -- sp[4 * argc]       : receiver
    // -----------------------------------
  
    // Load the FunctionTemplateInfo.
    __ LoadP(r6, FieldMemOperand(r4, JSFunction::kSharedFunctionInfoOffset));
    __ LoadP(r6, FieldMemOperand(r6, SharedFunctionInfo::kFunctionDataOffset));
  
    // Do the compatible receiver check.
    Label receiver_check_failed;
    __ ShiftLeftImm(r11, r3, Operand(kPointerSizeLog2));
    __ LoadPX(r5, MemOperand(sp, r11));
    CompatibleReceiverCheck(masm, r5, r6, &receiver_check_failed);
  
    // Get the callback offset from the FunctionTemplateInfo, and jump to the
    // beginning of the code.
    __ LoadP(r7, FieldMemOperand(r6, FunctionTemplateInfo::kCallCodeOffset));
    __ LoadP(r7, FieldMemOperand(r7, CallHandlerInfo::kFastHandlerOffset));
    __ addi(ip, r7, Operand(Code::kHeaderSize - kHeapObjectTag));
    __ JumpToJSEntry(ip);
  
    // Compatible receiver check failed: throw an Illegal Invocation exception.
    __ bind(&receiver_check_failed);
    // Drop the arguments (including the receiver);
    __ addi(r11, r11, Operand(kPointerSize));
    __ add(sp, sp, r11);
    __ TailCallRuntime(Runtime::kThrowIllegalInvocation);
  }
  
  static void Generate_OnStackReplacementHelper(MacroAssembler* masm,
                                                bool has_handler_frame) {
    // Lookup the function in the JavaScript frame.
    if (has_handler_frame) {
      __ LoadP(r3, MemOperand(fp, StandardFrameConstants::kCallerFPOffset));
      __ LoadP(r3, MemOperand(r3, JavaScriptFrameConstants::kFunctionOffset));
    } else {
      __ LoadP(r3, MemOperand(fp, JavaScriptFrameConstants::kFunctionOffset));
    }
  
    {
      FrameAndConstantPoolScope scope(masm, StackFrame::INTERNAL);
      // Pass function as argument.
      __ push(r3);
      __ CallRuntime(Runtime::kCompileForOnStackReplacement);
    }
  
    // If the code object is null, just return to the caller.
    Label skip;
    __ CmpSmiLiteral(r3, Smi::kZero, r0);
    __ bne(&skip);
    __ Ret();
  
    __ bind(&skip);
  
    // 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]
    __ LoadP(r4, FieldMemOperand(r3, Code::kDeoptimizationDataOffset));
  
    {
      ConstantPoolUnavailableScope constant_pool_unavailable(masm);
      __ addi(r3, r3, Operand(Code::kHeaderSize - kHeapObjectTag));  // Code start
  
      if (FLAG_enable_embedded_constant_pool) {
        __ LoadConstantPoolPointerRegisterFromCodeTargetAddress(r3);
      }
  
      // Load the OSR entrypoint offset from the deoptimization data.
      // <osr_offset> = <deopt_data>[#header_size + #osr_pc_offset]
      __ LoadP(r4, FieldMemOperand(
                       r4, FixedArray::OffsetOfElementAt(
                               DeoptimizationInputData::kOsrPcOffsetIndex)));
      __ SmiUntag(r4);
  
      // Compute the target address = code start + osr_offset
      __ add(r0, r3, r4);
  
      // And "return" to the OSR entry point of the function.
      __ mtlr(r0);
      __ blr();
    }
  }
  
  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 -------------
    //  -- r3    : argc
    //  -- sp[0] : argArray
    //  -- sp[4] : thisArg
    //  -- sp[8] : receiver
    // -----------------------------------
  
    // 1. Load receiver into r4, argArray into r3 (if present), remove all
    // arguments from the stack (including the receiver), and push thisArg (if
    // present) instead.
    {
      Label skip;
      Register arg_size = r5;
      Register new_sp = r6;
      Register scratch = r7;
      __ ShiftLeftImm(arg_size, r3, Operand(kPointerSizeLog2));
      __ add(new_sp, sp, arg_size);
      __ LoadRoot(r3, Heap::kUndefinedValueRootIndex);
      __ mr(scratch, r3);
      __ LoadP(r4, MemOperand(new_sp, 0));  // receiver
      __ cmpi(arg_size, Operand(kPointerSize));
      __ blt(&skip);
      __ LoadP(scratch, MemOperand(new_sp, 1 * -kPointerSize));  // thisArg
      __ beq(&skip);
      __ LoadP(r3, MemOperand(new_sp, 2 * -kPointerSize));  // argArray
      __ bind(&skip);
      __ mr(sp, new_sp);
      __ StoreP(scratch, MemOperand(sp, 0));
    }
  
    // ----------- S t a t e -------------
    //  -- r3    : argArray
    //  -- r4    : receiver
    //  -- sp[0] : thisArg
    // -----------------------------------
  
    // 2. Make sure the receiver is actually callable.
    Label receiver_not_callable;
    __ JumpIfSmi(r4, &receiver_not_callable);
    __ LoadP(r7, FieldMemOperand(r4, HeapObject::kMapOffset));
    __ lbz(r7, FieldMemOperand(r7, Map::kBitFieldOffset));
    __ TestBit(r7, Map::kIsCallable, r0);
    __ beq(&receiver_not_callable, cr0);
  
    // 3. Tail call with no arguments if argArray is null or undefined.
    Label no_arguments;
    __ JumpIfRoot(r3, Heap::kNullValueRootIndex, &no_arguments);
    __ JumpIfRoot(r3, Heap::kUndefinedValueRootIndex, &no_arguments);
  
    // 4a. Apply the receiver to the given argArray (passing undefined for
    // new.target).
    __ LoadRoot(r6, Heap::kUndefinedValueRootIndex);
    __ Jump(masm->isolate()->builtins()->Apply(), RelocInfo::CODE_TARGET);
  
    // 4b. The argArray is either null or undefined, so we tail call without any
    // arguments to the receiver.
    __ bind(&no_arguments);
    {
      __ li(r3, Operand::Zero());
      __ Jump(masm->isolate()->builtins()->Call(), RelocInfo::CODE_TARGET);
    }
  
    // 4c. The receiver is not callable, throw an appropriate TypeError.
    __ bind(&receiver_not_callable);
    {
      __ StoreP(r4, MemOperand(sp, 0));
      __ TailCallRuntime(Runtime::kThrowApplyNonFunction);
    }
  }
  
  // static
  void Builtins::Generate_FunctionPrototypeCall(MacroAssembler* masm) {
    // 1. Make sure we have at least one argument.
    // r3: actual number of arguments
    {
      Label done;
      __ cmpi(r3, Operand::Zero());
      __ bne(&done);
      __ PushRoot(Heap::kUndefinedValueRootIndex);
      __ addi(r3, r3, Operand(1));
      __ bind(&done);
    }
  
    // 2. Get the callable to call (passed as receiver) from the stack.
    // r3: actual number of arguments
    __ ShiftLeftImm(r5, r3, Operand(kPointerSizeLog2));
    __ LoadPX(r4, MemOperand(sp, r5));
  
    // 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.
    // r3: actual number of arguments
    // r4: callable
    {
      Label loop;
      // Calculate the copy start address (destination). Copy end address is sp.
      __ add(r5, sp, r5);
  
      __ mtctr(r3);
      __ bind(&loop);
      __ LoadP(ip, MemOperand(r5, -kPointerSize));
      __ StoreP(ip, MemOperand(r5));
      __ subi(r5, r5, Operand(kPointerSize));
      __ bdnz(&loop);
      // Adjust the actual number of arguments and remove the top element
      // (which is a copy of the last argument).
      __ subi(r3, r3, 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 -------------
    //  -- r3     : argc
    //  -- sp[0]  : argumentsList
    //  -- sp[4]  : thisArgument
    //  -- sp[8]  : target
    //  -- sp[12] : receiver
    // -----------------------------------
  
    // 1. Load target into r4 (if present), argumentsList into r3 (if present),
    // remove all arguments from the stack (including the receiver), and push
    // thisArgument (if present) instead.
    {
      Label skip;
      Register arg_size = r5;
      Register new_sp = r6;
      Register scratch = r7;
      __ ShiftLeftImm(arg_size, r3, Operand(kPointerSizeLog2));
      __ add(new_sp, sp, arg_size);
      __ LoadRoot(r4, Heap::kUndefinedValueRootIndex);
      __ mr(scratch, r4);
      __ mr(r3, r4);
      __ cmpi(arg_size, Operand(kPointerSize));
      __ blt(&skip);
      __ LoadP(r4, MemOperand(new_sp, 1 * -kPointerSize));  // target
      __ beq(&skip);
      __ LoadP(scratch, MemOperand(new_sp, 2 * -kPointerSize));  // thisArgument
      __ cmpi(arg_size, Operand(2 * kPointerSize));
      __ beq(&skip);
      __ LoadP(r3, MemOperand(new_sp, 3 * -kPointerSize));  // argumentsList
      __ bind(&skip);
      __ mr(sp, new_sp);
      __ StoreP(scratch, MemOperand(sp, 0));
    }
  
    // ----------- S t a t e -------------
    //  -- r3    : argumentsList
    //  -- r4    : target
    //  -- sp[0] : thisArgument
    // -----------------------------------
  
    // 2. Make sure the target is actually callable.
    Label target_not_callable;
    __ JumpIfSmi(r4, &target_not_callable);
    __ LoadP(r7, FieldMemOperand(r4, HeapObject::kMapOffset));
    __ lbz(r7, FieldMemOperand(r7, Map::kBitFieldOffset));
    __ TestBit(r7, Map::kIsCallable, r0);
    __ beq(&target_not_callable, cr0);
  
    // 3a. Apply the target to the given argumentsList (passing undefined for
    // new.target).
    __ LoadRoot(r6, Heap::kUndefinedValueRootIndex);
    __ Jump(masm->isolate()->builtins()->Apply(), RelocInfo::CODE_TARGET);
  
    // 3b. The target is not callable, throw an appropriate TypeError.
    __ bind(&target_not_callable);
    {
      __ StoreP(r4, MemOperand(sp, 0));
      __ TailCallRuntime(Runtime::kThrowApplyNonFunction);
    }
  }
  
  void Builtins::Generate_ReflectConstruct(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- r3     : argc
    //  -- sp[0]  : new.target (optional)
    //  -- sp[4]  : argumentsList
    //  -- sp[8]  : target
    //  -- sp[12] : receiver
    // -----------------------------------
  
    // 1. Load target into r4 (if present), argumentsList into r3 (if present),
    // new.target into r6 (if present, otherwise use target), remove all
    // arguments from the stack (including the receiver), and push thisArgument
    // (if present) instead.
    {
      Label skip;
      Register arg_size = r5;
      Register new_sp = r7;
      __ ShiftLeftImm(arg_size, r3, Operand(kPointerSizeLog2));
      __ add(new_sp, sp, arg_size);
      __ LoadRoot(r4, Heap::kUndefinedValueRootIndex);
      __ mr(r3, r4);
      __ mr(r6, r4);
      __ StoreP(r4, MemOperand(new_sp, 0));  // receiver (undefined)
      __ cmpi(arg_size, Operand(kPointerSize));
      __ blt(&skip);
      __ LoadP(r4, MemOperand(new_sp, 1 * -kPointerSize));  // target
      __ mr(r6, r4);  // new.target defaults to target
      __ beq(&skip);
      __ LoadP(r3, MemOperand(new_sp, 2 * -kPointerSize));  // argumentsList
      __ cmpi(arg_size, Operand(2 * kPointerSize));
      __ beq(&skip);
      __ LoadP(r6, MemOperand(new_sp, 3 * -kPointerSize));  // new.target
      __ bind(&skip);
      __ mr(sp, new_sp);
    }
  
    // ----------- S t a t e -------------
    //  -- r3    : argumentsList
    //  -- r6    : new.target
    //  -- r4    : target
    //  -- sp[0] : receiver (undefined)
    // -----------------------------------
  
    // 2. Make sure the target is actually a constructor.
    Label target_not_constructor;
    __ JumpIfSmi(r4, &target_not_constructor);
    __ LoadP(r7, FieldMemOperand(r4, HeapObject::kMapOffset));
    __ lbz(r7, FieldMemOperand(r7, Map::kBitFieldOffset));
    __ TestBit(r7, Map::kIsConstructor, r0);
    __ beq(&target_not_constructor, cr0);
  
    // 3. Make sure the target is actually a constructor.
    Label new_target_not_constructor;
    __ JumpIfSmi(r6, &new_target_not_constructor);
    __ LoadP(r7, FieldMemOperand(r6, HeapObject::kMapOffset));
    __ lbz(r7, FieldMemOperand(r7, Map::kBitFieldOffset));
    __ TestBit(r7, Map::kIsConstructor, r0);
    __ beq(&new_target_not_constructor, cr0);
  
    // 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);
    {
      __ StoreP(r4, MemOperand(sp, 0));
      __ TailCallRuntime(Runtime::kThrowCalledNonCallable);
    }
  
    // 4c. The new.target is not a constructor, throw an appropriate TypeError.
    __ bind(&new_target_not_constructor);
    {
      __ StoreP(r6, MemOperand(sp, 0));
      __ TailCallRuntime(Runtime::kThrowCalledNonCallable);
    }
  }
  
  static void EnterArgumentsAdaptorFrame(MacroAssembler* masm) {
    __ SmiTag(r3);
    __ LoadSmiLiteral(r7, Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR));
    __ mflr(r0);
    __ push(r0);
    if (FLAG_enable_embedded_constant_pool) {
      __ Push(fp, kConstantPoolRegister, r7, r4, r3);
    } else {
      __ Push(fp, r7, r4, r3);
    }
    __ addi(fp, sp, Operand(StandardFrameConstants::kFixedFrameSizeFromFp +
                            kPointerSize));
  }
  
  static void LeaveArgumentsAdaptorFrame(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- r3 : result being passed through
    // -----------------------------------
    // Get the number of arguments passed (as a smi), tear down the frame and
    // then tear down the parameters.
    __ LoadP(r4, MemOperand(fp, -(StandardFrameConstants::kFixedFrameSizeFromFp +
                                  kPointerSize)));
    int stack_adjustment = kPointerSize;  // adjust for receiver
    __ LeaveFrame(StackFrame::ARGUMENTS_ADAPTOR, stack_adjustment);
    __ SmiToPtrArrayOffset(r0, r4);
    __ add(sp, sp, r0);
  }
  
  // static
  void Builtins::Generate_Apply(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- r3    : argumentsList
    //  -- r4    : target
    //  -- r6    : new.target (checked to be constructor or undefined)
    //  -- sp[0] : thisArgument
    // -----------------------------------
  
    // Create the list of arguments from the array-like argumentsList.
    {
      Label create_arguments, create_array, create_runtime, done_create;
      __ JumpIfSmi(r3, &create_runtime);
  
      // Load the map of argumentsList into r5.
      __ LoadP(r5, FieldMemOperand(r3, HeapObject::kMapOffset));
  
      // Load native context into r7.
      __ LoadP(r7, NativeContextMemOperand());
  
      // Check if argumentsList is an (unmodified) arguments object.
      __ LoadP(ip, ContextMemOperand(r7, Context::SLOPPY_ARGUMENTS_MAP_INDEX));
      __ cmp(ip, r5);
      __ beq(&create_arguments);
      __ LoadP(ip, ContextMemOperand(r7, Context::STRICT_ARGUMENTS_MAP_INDEX));
      __ cmp(ip, r5);
      __ beq(&create_arguments);
  
      // Check if argumentsList is a fast JSArray.
      __ CompareInstanceType(r5, ip, JS_ARRAY_TYPE);
      __ beq(&create_array);
  
      // Ask the runtime to create the list (actually a FixedArray).
      __ bind(&create_runtime);
      {
        FrameAndConstantPoolScope scope(masm, StackFrame::INTERNAL);
        __ Push(r4, r6, r3);
        __ CallRuntime(Runtime::kCreateListFromArrayLike);
        __ Pop(r4, r6);
        __ LoadP(r5, FieldMemOperand(r3, FixedArray::kLengthOffset));
        __ SmiUntag(r5);
      }
      __ b(&done_create);
  
      // Try to create the list from an arguments object.
      __ bind(&create_arguments);
      __ LoadP(r5, FieldMemOperand(r3, JSArgumentsObject::kLengthOffset));
      __ LoadP(r7, FieldMemOperand(r3, JSObject::kElementsOffset));
      __ LoadP(ip, FieldMemOperand(r7, FixedArray::kLengthOffset));
      __ cmp(r5, ip);
      __ bne(&create_runtime);
      __ SmiUntag(r5);
      __ mr(r3, r7);
      __ b(&done_create);
  
      // Try to create the list from a JSArray object.
      __ bind(&create_array);
      __ lbz(r5, FieldMemOperand(r5, Map::kBitField2Offset));
      __ DecodeField<Map::ElementsKindBits>(r5);
      STATIC_ASSERT(FAST_SMI_ELEMENTS == 0);
      STATIC_ASSERT(FAST_HOLEY_SMI_ELEMENTS == 1);
      STATIC_ASSERT(FAST_ELEMENTS == 2);
      __ cmpi(r5, Operand(FAST_ELEMENTS));
      __ bgt(&create_runtime);
      __ cmpi(r5, Operand(FAST_HOLEY_SMI_ELEMENTS));
      __ beq(&create_runtime);
      __ LoadP(r5, FieldMemOperand(r3, JSArray::kLengthOffset));
      __ LoadP(r3, FieldMemOperand(r3, JSArray::kElementsOffset));
      __ SmiUntag(r5);
  
      __ 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(ip, Heap::kRealStackLimitRootIndex);
      // Make ip the space we have left. The stack might already be overflowed
      // here which will cause ip to become negative.
      __ sub(ip, sp, ip);
      // Check if the arguments will overflow the stack.
      __ ShiftLeftImm(r0, r5, Operand(kPointerSizeLog2));
      __ cmp(ip, r0);  // Signed comparison.
      __ bgt(&done);
      __ TailCallRuntime(Runtime::kThrowStackOverflow);
      __ bind(&done);
    }
  
    // ----------- S t a t e -------------
    //  -- r4    : target
    //  -- r3    : args (a FixedArray built from argumentsList)
    //  -- r5    : len (number of elements to push from args)
    //  -- r6    : new.target (checked to be constructor or undefined)
    //  -- sp[0] : thisArgument
    // -----------------------------------
  
    // Push arguments onto the stack (thisArgument is already on the stack).
    {
      Label loop, no_args;
      __ cmpi(r5, Operand::Zero());
      __ beq(&no_args);
      __ addi(r3, r3,
              Operand(FixedArray::kHeaderSize - kHeapObjectTag - kPointerSize));
      __ mtctr(r5);
      __ bind(&loop);
      __ LoadPU(r0, MemOperand(r3, kPointerSize));
      __ push(r0);
      __ bdnz(&loop);
      __ bind(&no_args);
      __ mr(r3, r5);
    }
  
    // Dispatch to Call or Construct depending on whether new.target is undefined.
    {
      __ CompareRoot(r6, Heap::kUndefinedValueRootIndex);
      __ Jump(masm->isolate()->builtins()->Call(), RelocInfo::CODE_TARGET, eq);
      __ 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());
    __ mov(scratch1, Operand(is_tail_call_elimination_enabled));
    __ lbz(scratch1, MemOperand(scratch1));
    __ cmpi(scratch1, Operand::Zero());
    __ beq(&done);
  
    // Drop possible interpreter handler/stub frame.
    {
      Label no_interpreter_frame;
      __ LoadP(scratch3,
               MemOperand(fp, CommonFrameConstants::kContextOrFrameTypeOffset));
      __ CmpSmiLiteral(scratch3, Smi::FromInt(StackFrame::STUB), r0);
      __ bne(&no_interpreter_frame);
      __ LoadP(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;
    __ LoadP(scratch2, MemOperand(fp, StandardFrameConstants::kCallerFPOffset));
    __ LoadP(
        scratch3,
        MemOperand(scratch2, CommonFrameConstants::kContextOrFrameTypeOffset));
    __ CmpSmiLiteral(scratch3, Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR), r0);
    __ bne(&no_arguments_adaptor);
  
    // Drop current frame and load arguments count from arguments adaptor frame.
    __ mr(fp, scratch2);
    __ LoadP(caller_args_count_reg,
             MemOperand(fp, ArgumentsAdaptorFrameConstants::kLengthOffset));
    __ SmiUntag(caller_args_count_reg);
    __ b(&formal_parameter_count_loaded);
  
    __ bind(&no_arguments_adaptor);
    // Load caller's formal parameter count
    __ LoadP(scratch1,
             MemOperand(fp, ArgumentsAdaptorFrameConstants::kFunctionOffset));
    __ LoadP(scratch1,
             FieldMemOperand(scratch1, JSFunction::kSharedFunctionInfoOffset));
    __ LoadWordArith(
        caller_args_count_reg,
        FieldMemOperand(scratch1,
                        SharedFunctionInfo::kFormalParameterCountOffset));
  #if !V8_TARGET_ARCH_PPC64
    __ SmiUntag(caller_args_count_reg);
  #endif
  
    __ 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 -------------
    //  -- r3 : the number of arguments (not including the receiver)
    //  -- r4 : the function to call (checked to be a JSFunction)
    // -----------------------------------
    __ AssertFunction(r4);
  
    // See ES6 section 9.2.1 [[Call]] ( thisArgument, argumentsList)
    // Check that the function is not a "classConstructor".
    Label class_constructor;
    __ LoadP(r5, FieldMemOperand(r4, JSFunction::kSharedFunctionInfoOffset));
    __ lwz(r6, FieldMemOperand(r5, SharedFunctionInfo::kCompilerHintsOffset));
    __ TestBitMask(r6, FunctionKind::kClassConstructor
                           << SharedFunctionInfo::kFunctionKindShift,
                   r0);
    __ bne(&class_constructor, cr0);
  
    // 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.
    __ LoadP(cp, FieldMemOperand(r4, JSFunction::kContextOffset));
    // We need to convert the receiver for non-native sloppy mode functions.
    Label done_convert;
    __ andi(r0, r6, Operand((1 << SharedFunctionInfo::kStrictModeBit) |
                            (1 << SharedFunctionInfo::kNativeBit)));
    __ bne(&done_convert, cr0);
    {
      // ----------- S t a t e -------------
      //  -- r3 : the number of arguments (not including the receiver)
      //  -- r4 : the function to call (checked to be a JSFunction)
      //  -- r5 : the shared function info.
      //  -- cp : the function context.
      // -----------------------------------
  
      if (mode == ConvertReceiverMode::kNullOrUndefined) {
        // Patch receiver to global proxy.
        __ LoadGlobalProxy(r6);
      } else {
        Label convert_to_object, convert_receiver;
        __ ShiftLeftImm(r6, r3, Operand(kPointerSizeLog2));
        __ LoadPX(r6, MemOperand(sp, r6));
        __ JumpIfSmi(r6, &convert_to_object);
        STATIC_ASSERT(LAST_JS_RECEIVER_TYPE == LAST_TYPE);
        __ CompareObjectType(r6, r7, r7, FIRST_JS_RECEIVER_TYPE);
        __ bge(&done_convert);
        if (mode != ConvertReceiverMode::kNotNullOrUndefined) {
          Label convert_global_proxy;
          __ JumpIfRoot(r6, Heap::kUndefinedValueRootIndex,
                        &convert_global_proxy);
          __ JumpIfNotRoot(r6, Heap::kNullValueRootIndex, &convert_to_object);
          __ bind(&convert_global_proxy);
          {
            // Patch receiver to global proxy.
            __ LoadGlobalProxy(r6);
          }
          __ b(&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?)
          FrameAndConstantPoolScope scope(masm, StackFrame::INTERNAL);
          __ SmiTag(r3);
          __ Push(r3, r4);
          __ mr(r3, r6);
          __ Push(cp);
          __ Call(masm->isolate()->builtins()->ToObject(),
                  RelocInfo::CODE_TARGET);
          __ Pop(cp);
          __ mr(r6, r3);
          __ Pop(r3, r4);
          __ SmiUntag(r3);
        }
        __ LoadP(r5, FieldMemOperand(r4, JSFunction::kSharedFunctionInfoOffset));
        __ bind(&convert_receiver);
      }
      __ ShiftLeftImm(r7, r3, Operand(kPointerSizeLog2));
      __ StorePX(r6, MemOperand(sp, r7));
    }
    __ bind(&done_convert);
  
    // ----------- S t a t e -------------
    //  -- r3 : the number of arguments (not including the receiver)
    //  -- r4 : the function to call (checked to be a JSFunction)
    //  -- r5 : the shared function info.
    //  -- cp : the function context.
    // -----------------------------------
  
    if (tail_call_mode == TailCallMode::kAllow) {
      PrepareForTailCall(masm, r3, r6, r7, r8);
    }
  
    __ LoadWordArith(
        r5, FieldMemOperand(r5, SharedFunctionInfo::kFormalParameterCountOffset));
  #if !V8_TARGET_ARCH_PPC64
    __ SmiUntag(r5);
  #endif
    ParameterCount actual(r3);
    ParameterCount expected(r5);
    __ InvokeFunctionCode(r4, no_reg, expected, actual, JUMP_FUNCTION,
                          CheckDebugStepCallWrapper());
  
    // The function is a "classConstructor", need to raise an exception.
    __ bind(&class_constructor);
    {
      FrameAndConstantPoolScope frame(masm, StackFrame::INTERNAL);
      __ push(r4);
      __ CallRuntime(Runtime::kThrowConstructorNonCallableError);
    }
  }
  
  namespace {
  
  void Generate_PushBoundArguments(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- r3 : the number of arguments (not including the receiver)
    //  -- r4 : target (checked to be a JSBoundFunction)
    //  -- r6 : new.target (only in case of [[Construct]])
    // -----------------------------------
  
    // Load [[BoundArguments]] into r5 and length of that into r7.
    Label no_bound_arguments;
    __ LoadP(r5, FieldMemOperand(r4, JSBoundFunction::kBoundArgumentsOffset));
    __ LoadP(r7, FieldMemOperand(r5, FixedArray::kLengthOffset));
    __ SmiUntag(r7, SetRC);
    __ beq(&no_bound_arguments, cr0);
    {
      // ----------- S t a t e -------------
      //  -- r3 : the number of arguments (not including the receiver)
      //  -- r4 : target (checked to be a JSBoundFunction)
      //  -- r5 : the [[BoundArguments]] (implemented as FixedArray)
      //  -- r6 : new.target (only in case of [[Construct]])
      //  -- r7 : the number of [[BoundArguments]]
      // -----------------------------------
  
      // Reserve stack space for the [[BoundArguments]].
      {
        Label done;
        __ mr(r9, sp);  // preserve previous stack pointer
        __ ShiftLeftImm(r10, r7, Operand(kPointerSizeLog2));
        __ sub(sp, sp, r10);
        // 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".
        __ CompareRoot(sp, Heap::kRealStackLimitRootIndex);
        __ bgt(&done);  // Signed comparison.
        // Restore the stack pointer.
        __ mr(sp, r9);
        {
          FrameScope scope(masm, StackFrame::MANUAL);
          __ EnterFrame(StackFrame::INTERNAL);
          __ CallRuntime(Runtime::kThrowStackOverflow);
        }
        __ bind(&done);
      }
  
      // Relocate arguments down the stack.
      //  -- r3 : the number of arguments (not including the receiver)
      //  -- r9 : the previous stack pointer
      //  -- r10: the size of the [[BoundArguments]]
      {
        Label skip, loop;
        __ li(r8, Operand::Zero());
        __ cmpi(r3, Operand::Zero());
        __ beq(&skip);
        __ mtctr(r3);
        __ bind(&loop);
        __ LoadPX(r0, MemOperand(r9, r8));
        __ StorePX(r0, MemOperand(sp, r8));
        __ addi(r8, r8, Operand(kPointerSize));
        __ bdnz(&loop);
        __ bind(&skip);
      }
  
      // Copy [[BoundArguments]] to the stack (below the arguments).
      {
        Label loop;
        __ addi(r5, r5, Operand(FixedArray::kHeaderSize - kHeapObjectTag));
        __ add(r5, r5, r10);
        __ mtctr(r7);
        __ bind(&loop);
        __ LoadPU(r0, MemOperand(r5, -kPointerSize));
        __ StorePX(r0, MemOperand(sp, r8));
        __ addi(r8, r8, Operand(kPointerSize));
        __ bdnz(&loop);
        __ add(r3, r3, r7);
      }
    }
    __ bind(&no_bound_arguments);
  }
  
  }  // namespace
  
  // static
  void Builtins::Generate_CallBoundFunctionImpl(MacroAssembler* masm,
                                                TailCallMode tail_call_mode) {
    // ----------- S t a t e -------------
    //  -- r3 : the number of arguments (not including the receiver)
    //  -- r4 : the function to call (checked to be a JSBoundFunction)
    // -----------------------------------
    __ AssertBoundFunction(r4);
  
    if (tail_call_mode == TailCallMode::kAllow) {
      PrepareForTailCall(masm, r3, r6, r7, r8);
    }
  
    // Patch the receiver to [[BoundThis]].
    __ LoadP(ip, FieldMemOperand(r4, JSBoundFunction::kBoundThisOffset));
    __ ShiftLeftImm(r0, r3, Operand(kPointerSizeLog2));
    __ StorePX(ip, MemOperand(sp, r0));
  
    // Push the [[BoundArguments]] onto the stack.
    Generate_PushBoundArguments(masm);
  
    // Call the [[BoundTargetFunction]] via the Call builtin.
    __ LoadP(r4,
             FieldMemOperand(r4, JSBoundFunction::kBoundTargetFunctionOffset));
    __ mov(ip, Operand(ExternalReference(Builtins::kCall_ReceiverIsAny,
                                         masm->isolate())));
    __ LoadP(ip, MemOperand(ip));
    __ addi(ip, ip, Operand(Code::kHeaderSize - kHeapObjectTag));
    __ JumpToJSEntry(ip);
  }
  
  // static
  void Builtins::Generate_Call(MacroAssembler* masm, ConvertReceiverMode mode,
                               TailCallMode tail_call_mode) {
    // ----------- S t a t e -------------
    //  -- r3 : the number of arguments (not including the receiver)
    //  -- r4 : the target to call (can be any Object).
    // -----------------------------------
  
    Label non_callable, non_function, non_smi;
    __ JumpIfSmi(r4, &non_callable);
    __ bind(&non_smi);
    __ CompareObjectType(r4, r7, r8, JS_FUNCTION_TYPE);
    __ Jump(masm->isolate()->builtins()->CallFunction(mode, tail_call_mode),
            RelocInfo::CODE_TARGET, eq);
    __ cmpi(r8, Operand(JS_BOUND_FUNCTION_TYPE));
    __ Jump(masm->isolate()->builtins()->CallBoundFunction(tail_call_mode),
            RelocInfo::CODE_TARGET, eq);
  
    // Check if target has a [[Call]] internal method.
    __ lbz(r7, FieldMemOperand(r7, Map::kBitFieldOffset));
    __ TestBit(r7, Map::kIsCallable, r0);
    __ beq(&non_callable, cr0);
  
    __ cmpi(r8, Operand(JS_PROXY_TYPE));
    __ bne(&non_function);
  
    // 0. Prepare for tail call if necessary.
    if (tail_call_mode == TailCallMode::kAllow) {
      PrepareForTailCall(masm, r3, r6, r7, r8);
    }
  
    // 1. Runtime fallback for Proxy [[Call]].
    __ Push(r4);
    // Increase the arguments size to include the pushed function and the
    // existing receiver on the stack.
    __ addi(r3, r3, Operand(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 the (original) target.
    __ ShiftLeftImm(r8, r3, Operand(kPointerSizeLog2));
    __ StorePX(r4, MemOperand(sp, r8));
    // Let the "call_as_function_delegate" take care of the rest.
    __ LoadNativeContextSlot(Context::CALL_AS_FUNCTION_DELEGATE_INDEX, r4);
    __ Jump(masm->isolate()->builtins()->CallFunction(
                ConvertReceiverMode::kNotNullOrUndefined, tail_call_mode),
            RelocInfo::CODE_TARGET);
  
    // 3. Call to something that is not callable.
    __ bind(&non_callable);
    {
      FrameAndConstantPoolScope scope(masm, StackFrame::INTERNAL);
      __ Push(r4);
      __ CallRuntime(Runtime::kThrowCalledNonCallable);
    }
  }
  
  // static
  void Builtins::Generate_ConstructFunction(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- r3 : the number of arguments (not including the receiver)
    //  -- r4 : the constructor to call (checked to be a JSFunction)
    //  -- r6 : the new target (checked to be a constructor)
    // -----------------------------------
    __ AssertFunction(r4);
  
    // Calling convention for function specific ConstructStubs require
    // r5 to contain either an AllocationSite or undefined.
    __ LoadRoot(r5, Heap::kUndefinedValueRootIndex);
  
    // Tail call to the function-specific construct stub (still in the caller
    // context at this point).
    __ LoadP(r7, FieldMemOperand(r4, JSFunction::kSharedFunctionInfoOffset));
    __ LoadP(r7, FieldMemOperand(r7, SharedFunctionInfo::kConstructStubOffset));
    __ addi(ip, r7, Operand(Code::kHeaderSize - kHeapObjectTag));
    __ JumpToJSEntry(ip);
  }
  
  // static
  void Builtins::Generate_ConstructBoundFunction(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- r3 : the number of arguments (not including the receiver)
    //  -- r4 : the function to call (checked to be a JSBoundFunction)
    //  -- r6 : the new target (checked to be a constructor)
    // -----------------------------------
    __ AssertBoundFunction(r4);
  
    // Push the [[BoundArguments]] onto the stack.
    Generate_PushBoundArguments(masm);
  
    // Patch new.target to [[BoundTargetFunction]] if new.target equals target.
    Label skip;
    __ cmp(r4, r6);
    __ bne(&skip);
    __ LoadP(r6,
             FieldMemOperand(r4, JSBoundFunction::kBoundTargetFunctionOffset));
    __ bind(&skip);
  
    // Construct the [[BoundTargetFunction]] via the Construct builtin.
    __ LoadP(r4,
             FieldMemOperand(r4, JSBoundFunction::kBoundTargetFunctionOffset));
    __ mov(ip, Operand(ExternalReference(Builtins::kConstruct, masm->isolate())));
    __ LoadP(ip, MemOperand(ip));
    __ addi(ip, ip, Operand(Code::kHeaderSize - kHeapObjectTag));
    __ JumpToJSEntry(ip);
  }
  
  // static
  void Builtins::Generate_ConstructProxy(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- r3 : the number of arguments (not including the receiver)
    //  -- r4 : the constructor to call (checked to be a JSProxy)
    //  -- r6 : 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(r4, r6);
    // Include the pushed new_target, constructor and the receiver.
    __ addi(r3, r3, 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 -------------
    //  -- r3 : the number of arguments (not including the receiver)
    //  -- r4 : the constructor to call (can be any Object)
    //  -- r6 : 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(r4, &non_constructor);
  
    // Dispatch based on instance type.
    __ CompareObjectType(r4, r7, r8, JS_FUNCTION_TYPE);
    __ Jump(masm->isolate()->builtins()->ConstructFunction(),
            RelocInfo::CODE_TARGET, eq);
  
    // Check if target has a [[Construct]] internal method.
    __ lbz(r5, FieldMemOperand(r7, Map::kBitFieldOffset));
    __ TestBit(r5, Map::kIsConstructor, r0);
    __ beq(&non_constructor, cr0);
  
    // Only dispatch to bound functions after checking whether they are
    // constructors.
    __ cmpi(r8, Operand(JS_BOUND_FUNCTION_TYPE));
    __ Jump(masm->isolate()->builtins()->ConstructBoundFunction(),
            RelocInfo::CODE_TARGET, eq);
  
    // Only dispatch to proxies after checking whether they are constructors.
    __ cmpi(r8, Operand(JS_PROXY_TYPE));
    __ Jump(masm->isolate()->builtins()->ConstructProxy(), RelocInfo::CODE_TARGET,
            eq);
  
    // Called Construct on an exotic Object with a [[Construct]] internal method.
    {
      // Overwrite the original receiver with the (original) target.
      __ ShiftLeftImm(r8, r3, Operand(kPointerSizeLog2));
      __ StorePX(r4, MemOperand(sp, r8));
      // Let the "call_as_constructor_delegate" take care of the rest.
      __ LoadNativeContextSlot(Context::CALL_AS_CONSTRUCTOR_DELEGATE_INDEX, r4);
      __ 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 -------------
    //  -- r4 : requested object size (untagged)
    //  -- lr : return address
    // -----------------------------------
    __ SmiTag(r4);
    __ Push(r4);
    __ LoadSmiLiteral(cp, Smi::kZero);
    __ TailCallRuntime(Runtime::kAllocateInNewSpace);
  }
  
  // static
  void Builtins::Generate_AllocateInOldSpace(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- r4 : requested object size (untagged)
    //  -- lr : return address
    // -----------------------------------
    __ SmiTag(r4);
    __ LoadSmiLiteral(r5, Smi::FromInt(AllocateTargetSpace::encode(OLD_SPACE)));
    __ Push(r4, r5);
    __ LoadSmiLiteral(cp, Smi::kZero);
    __ TailCallRuntime(Runtime::kAllocateInTargetSpace);
  }
  
  // static
  void Builtins::Generate_Abort(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- r4 : message_id as Smi
    //  -- lr : return address
    // -----------------------------------
    __ push(r4);
    __ LoadSmiLiteral(cp, Smi::kZero);
    __ TailCallRuntime(Runtime::kAbort);
  }
  
  void Builtins::Generate_ArgumentsAdaptorTrampoline(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- r3 : actual number of arguments
    //  -- r4 : function (passed through to callee)
    //  -- r5 : expected number of arguments
    //  -- r6 : new target (passed through to callee)
    // -----------------------------------
  
    Label invoke, dont_adapt_arguments, stack_overflow;
  
    Label enough, too_few;
    __ LoadP(ip, FieldMemOperand(r4, JSFunction::kCodeEntryOffset));
    __ cmp(r3, r5);
    __ blt(&too_few);
    __ cmpi(r5, Operand(SharedFunctionInfo::kDontAdaptArgumentsSentinel));
    __ beq(&dont_adapt_arguments);
  
    {  // Enough parameters: actual >= expected
      __ bind(&enough);
      EnterArgumentsAdaptorFrame(masm);
      Generate_StackOverflowCheck(masm, r5, r8, &stack_overflow);
  
      // Calculate copy start address into r3 and copy end address into r7.
      // r3: actual number of arguments as a smi
      // r4: function
      // r5: expected number of arguments
      // r6: new target (passed through to callee)
      // ip: code entry to call
      __ SmiToPtrArrayOffset(r3, r3);
      __ add(r3, r3, fp);
      // adjust for return address and receiver
      __ addi(r3, r3, Operand(2 * kPointerSize));
      __ ShiftLeftImm(r7, r5, Operand(kPointerSizeLog2));
      __ sub(r7, r3, r7);
  
      // Copy the arguments (including the receiver) to the new stack frame.
      // r3: copy start address
      // r4: function
      // r5: expected number of arguments
      // r6: new target (passed through to callee)
      // r7: copy end address
      // ip: code entry to call
  
      Label copy;
      __ bind(&copy);
      __ LoadP(r0, MemOperand(r3, 0));
      __ push(r0);
      __ cmp(r3, r7);  // Compare before moving to next argument.
      __ subi(r3, r3, Operand(kPointerSize));
      __ bne(&copy);
  
      __ b(&invoke);
    }
  
    {  // Too few parameters: Actual < expected
      __ bind(&too_few);
  
      EnterArgumentsAdaptorFrame(masm);
      Generate_StackOverflowCheck(masm, r5, r8, &stack_overflow);
  
      // Calculate copy start address into r0 and copy end address is fp.
      // r3: actual number of arguments as a smi
      // r4: function
      // r5: expected number of arguments
      // r6: new target (passed through to callee)
      // ip: code entry to call
      __ SmiToPtrArrayOffset(r3, r3);
      __ add(r3, r3, fp);
  
      // Copy the arguments (including the receiver) to the new stack frame.
      // r3: copy start address
      // r4: function
      // r5: expected number of arguments
      // r6: new target (passed through to callee)
      // ip: code entry to call
      Label copy;
      __ bind(&copy);
      // Adjust load for return address and receiver.
      __ LoadP(r0, MemOperand(r3, 2 * kPointerSize));
      __ push(r0);
      __ cmp(r3, fp);  // Compare before moving to next argument.
      __ subi(r3, r3, Operand(kPointerSize));
      __ bne(&copy);
  
      // Fill the remaining expected arguments with undefined.
      // r4: function
      // r5: expected number of arguments
      // r6: new target (passed through to callee)
      // ip: code entry to call
      __ LoadRoot(r0, Heap::kUndefinedValueRootIndex);
      __ ShiftLeftImm(r7, r5, Operand(kPointerSizeLog2));
      __ sub(r7, fp, r7);
      // Adjust for frame.
      __ subi(r7, r7, Operand(StandardFrameConstants::kFixedFrameSizeFromFp +
                              2 * kPointerSize));
  
      Label fill;
      __ bind(&fill);
      __ push(r0);
      __ cmp(sp, r7);
      __ bne(&fill);
    }
  
    // Call the entry point.
    __ bind(&invoke);
    __ mr(r3, r5);
    // r3 : expected number of arguments
    // r4 : function (passed through to callee)
    // r6 : new target (passed through to callee)
    __ CallJSEntry(ip);
  
    // Store offset of return address for deoptimizer.
    masm->isolate()->heap()->SetArgumentsAdaptorDeoptPCOffset(masm->pc_offset());
  
    // Exit frame and return.
    LeaveArgumentsAdaptorFrame(masm);
    __ blr();
  
    // -------------------------------------------
    // Dont adapt arguments.
    // -------------------------------------------
    __ bind(&dont_adapt_arguments);
    __ JumpToJSEntry(ip);
  
    __ bind(&stack_overflow);
    {
      FrameScope frame(masm, StackFrame::MANUAL);
      __ CallRuntime(Runtime::kThrowStackOverflow);
      __ bkpt(0);
    }
  }
  
  #undef __
  }  // namespace internal
  }  // namespace v8
  
  #endif  // V8_TARGET_ARCH_PPC
  