diff --git a/src/mips64/builtins-mips64.cc b/src/mips64/builtins-mips64.cc
index c95ff30..3a9980b 100644
--- a/src/mips64/builtins-mips64.cc
+++ b/src/mips64/builtins-mips64.cc
@@ -2,16 +2,12 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-
-
-#include "src/v8.h"
-
 #if V8_TARGET_ARCH_MIPS64
 
 #include "src/codegen.h"
-#include "src/debug.h"
+#include "src/debug/debug.h"
 #include "src/deoptimizer.h"
-#include "src/full-codegen.h"
+#include "src/full-codegen/full-codegen.h"
 #include "src/runtime/runtime.h"
 
 namespace v8 {
@@ -26,27 +22,44 @@
                                 BuiltinExtraArguments extra_args) {
   // ----------- S t a t e -------------
   //  -- a0                 : number of arguments excluding receiver
-  //  -- a1                 : called function (only guaranteed when
-  //  --                      extra_args requires it)
-  //  -- cp                 : context
+  //  -- a1                 : target
+  //  -- a3                 : new.target
   //  -- sp[0]              : last argument
   //  -- ...
   //  -- sp[8 * (argc - 1)] : first argument
   //  -- sp[8 * agrc]       : receiver
   // -----------------------------------
+  __ AssertFunction(a1);
+
+  // Make sure we operate in the context of the called function (for example
+  // ConstructStubs implemented in C++ will be run in the context of the caller
+  // instead of the callee, due to the way that [[Construct]] is defined for
+  // ordinary functions).
+  __ ld(cp, FieldMemOperand(a1, JSFunction::kContextOffset));
 
   // Insert extra arguments.
   int num_extra_args = 0;
-  if (extra_args == NEEDS_CALLED_FUNCTION) {
-    num_extra_args = 1;
-    __ push(a1);
-  } else {
-    DCHECK(extra_args == NO_EXTRA_ARGUMENTS);
+  switch (extra_args) {
+    case BuiltinExtraArguments::kTarget:
+      __ Push(a1);
+      ++num_extra_args;
+      break;
+    case BuiltinExtraArguments::kNewTarget:
+      __ Push(a3);
+      ++num_extra_args;
+      break;
+    case BuiltinExtraArguments::kTargetAndNewTarget:
+      __ Push(a1, a3);
+      num_extra_args += 2;
+      break;
+    case BuiltinExtraArguments::kNone:
+      break;
   }
 
   // JumpToExternalReference expects a0 to contain the number of arguments
   // including the receiver and the extra arguments.
   __ Daddu(a0, a0, num_extra_args + 1);
+
   __ JumpToExternalReference(ExternalReference(id, masm->isolate()));
 }
 
@@ -54,32 +67,15 @@
 // Load the built-in InternalArray function from the current context.
 static void GenerateLoadInternalArrayFunction(MacroAssembler* masm,
                                               Register result) {
-  // Load the native context.
-
-  __ ld(result,
-        MemOperand(cp, Context::SlotOffset(Context::GLOBAL_OBJECT_INDEX)));
-  __ ld(result,
-        FieldMemOperand(result, GlobalObject::kNativeContextOffset));
   // Load the InternalArray function from the native context.
-  __ ld(result,
-         MemOperand(result,
-                    Context::SlotOffset(
-                        Context::INTERNAL_ARRAY_FUNCTION_INDEX)));
+  __ 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 native context.
-
-  __ ld(result,
-        MemOperand(cp, Context::SlotOffset(Context::GLOBAL_OBJECT_INDEX)));
-  __ ld(result,
-        FieldMemOperand(result, GlobalObject::kNativeContextOffset));
   // Load the Array function from the native context.
-  __ ld(result,
-        MemOperand(result,
-                   Context::SlotOffset(Context::ARRAY_FUNCTION_INDEX)));
+  __ LoadNativeContextSlot(Context::ARRAY_FUNCTION_INDEX, result);
 }
 
 
@@ -137,13 +133,15 @@
 
   // Run the native code for the Array function called as a normal function.
   // Tail call a stub.
+  __ mov(a3, a1);
   __ LoadRoot(a2, Heap::kUndefinedValueRootIndex);
   ArrayConstructorStub stub(masm->isolate());
   __ TailCallStub(&stub);
 }
 
 
-void Builtins::Generate_StringConstructCode(MacroAssembler* masm) {
+// static
+void Builtins::Generate_NumberConstructor(MacroAssembler* masm) {
   // ----------- S t a t e -------------
   //  -- a0                     : number of arguments
   //  -- a1                     : constructor function
@@ -151,134 +149,242 @@
   //  -- sp[(argc - n - 1) * 8] : arg[n] (zero based)
   //  -- sp[argc * 8]           : receiver
   // -----------------------------------
-  Counters* counters = masm->isolate()->counters();
-  __ IncrementCounter(counters->string_ctor_calls(), 1, a2, a3);
 
-  Register function = a1;
-  if (FLAG_debug_code) {
-    __ LoadGlobalFunction(Context::STRING_FUNCTION_INDEX, a2);
-    __ Assert(eq, kUnexpectedStringFunction, function, Operand(a2));
+  // 1. Load the first argument into a0 and get rid of the rest (including the
+  // receiver).
+  Label no_arguments;
+  {
+    __ Branch(USE_DELAY_SLOT, &no_arguments, eq, a0, Operand(zero_reg));
+    __ Dsubu(a0, a0, Operand(1));
+    __ dsll(a0, a0, kPointerSizeLog2);
+    __ Daddu(sp, a0, sp);
+    __ ld(a0, MemOperand(sp));
+    __ Drop(2);
   }
 
-  // Load the first arguments in a0 and get rid of the rest.
-  Label no_arguments;
-  __ Branch(&no_arguments, eq, a0, Operand(zero_reg));
-  // First args = sp[(argc - 1) * 8].
-  __ Dsubu(a0, a0, Operand(1));
-  __ dsll(a0, a0, kPointerSizeLog2);
-  __ Daddu(sp, a0, sp);
-  __ ld(a0, MemOperand(sp));
-  // sp now point to args[0], drop args[0] + receiver.
-  __ Drop(2);
+  // 2a. Convert first argument to number.
+  ToNumberStub stub(masm->isolate());
+  __ TailCallStub(&stub);
 
-  Register argument = a2;
-  Label not_cached, argument_is_string;
-  __ LookupNumberStringCache(a0,        // Input.
-                             argument,  // Result.
-                             a3,        // Scratch.
-                             a4,        // Scratch.
-                             a5,        // Scratch.
-                             &not_cached);
-  __ IncrementCounter(counters->string_ctor_cached_number(), 1, a3, a4);
-  __ bind(&argument_is_string);
+  // 2b. No arguments, return +0.
+  __ bind(&no_arguments);
+  __ Move(v0, Smi::FromInt(0));
+  __ DropAndRet(1);
+}
 
+
+void Builtins::Generate_NumberConstructor_ConstructStub(MacroAssembler* masm) {
   // ----------- S t a t e -------------
-  //  -- a2     : argument converted to string
-  //  -- a1     : constructor function
-  //  -- ra     : return address
+  //  -- a0                     : number of arguments
+  //  -- a1                     : constructor function
+  //  -- a3                     : new target
+  //  -- ra                     : return address
+  //  -- sp[(argc - n - 1) * 8] : arg[n] (zero based)
+  //  -- sp[argc * 8]           : receiver
   // -----------------------------------
 
-  Label gc_required;
-  __ Allocate(JSValue::kSize,
-              v0,  // Result.
-              a3,  // Scratch.
-              a4,  // Scratch.
-              &gc_required,
-              TAG_OBJECT);
+  // 1. Make sure we operate in the context of the called function.
+  __ ld(cp, FieldMemOperand(a1, JSFunction::kContextOffset));
 
-  // Initialising the String Object.
-  Register map = a3;
-  __ LoadGlobalFunctionInitialMap(function, map, a4);
-  if (FLAG_debug_code) {
-    __ lbu(a4, FieldMemOperand(map, Map::kInstanceSizeOffset));
-    __ Assert(eq, kUnexpectedStringWrapperInstanceSize,
-        a4, Operand(JSValue::kSize >> kPointerSizeLog2));
-    __ lbu(a4, FieldMemOperand(map, Map::kUnusedPropertyFieldsOffset));
-    __ Assert(eq, kUnexpectedUnusedPropertiesOfStringWrapper,
-        a4, Operand(zero_reg));
+  // 2. Load the first argument into a0 and get rid of the rest (including the
+  // receiver).
+  {
+    Label no_arguments, done;
+    __ Branch(USE_DELAY_SLOT, &no_arguments, eq, a0, Operand(zero_reg));
+    __ Dsubu(a0, a0, Operand(1));
+    __ dsll(a0, a0, kPointerSizeLog2);
+    __ Daddu(sp, a0, sp);
+    __ ld(a0, MemOperand(sp));
+    __ Drop(2);
+    __ jmp(&done);
+    __ bind(&no_arguments);
+    __ Move(a0, Smi::FromInt(0));
+    __ Drop(1);
+    __ bind(&done);
   }
-  __ sd(map, FieldMemOperand(v0, HeapObject::kMapOffset));
 
-  __ LoadRoot(a3, Heap::kEmptyFixedArrayRootIndex);
-  __ sd(a3, FieldMemOperand(v0, JSObject::kPropertiesOffset));
-  __ sd(a3, FieldMemOperand(v0, JSObject::kElementsOffset));
+  // 3. Make sure a0 is a number.
+  {
+    Label done_convert;
+    __ JumpIfSmi(a0, &done_convert);
+    __ GetObjectType(a0, a2, a2);
+    __ Branch(&done_convert, eq, t0, Operand(HEAP_NUMBER_TYPE));
+    {
+      FrameScope scope(masm, StackFrame::INTERNAL);
+      __ Push(a1, a3);
+      ToNumberStub stub(masm->isolate());
+      __ CallStub(&stub);
+      __ Move(a0, v0);
+      __ Pop(a1, a3);
+    }
+    __ bind(&done_convert);
+  }
 
-  __ sd(argument, FieldMemOperand(v0, JSValue::kValueOffset));
+  // 4. Check if new target and constructor differ.
+  Label new_object;
+  __ Branch(&new_object, ne, a1, Operand(a3));
 
-  // Ensure the object is fully initialized.
-  STATIC_ASSERT(JSValue::kSize == 4 * kPointerSize);
-
+  // 5. Allocate a JSValue wrapper for the number.
+  __ AllocateJSValue(v0, a1, a0, a2, t0, &new_object);
   __ Ret();
 
-  // The argument was not found in the number to string cache. Check
-  // if it's a string already before calling the conversion builtin.
-  Label convert_argument;
-  __ bind(&not_cached);
-  __ JumpIfSmi(a0, &convert_argument);
-
-  // Is it a String?
-  __ ld(a2, FieldMemOperand(a0, HeapObject::kMapOffset));
-  __ lbu(a3, FieldMemOperand(a2, Map::kInstanceTypeOffset));
-  STATIC_ASSERT(kNotStringTag != 0);
-  __ And(a4, a3, Operand(kIsNotStringMask));
-  __ Branch(&convert_argument, ne, a4, Operand(zero_reg));
-  __ mov(argument, a0);
-  __ IncrementCounter(counters->string_ctor_conversions(), 1, a3, a4);
-  __ Branch(&argument_is_string);
-
-  // Invoke the conversion builtin and put the result into a2.
-  __ bind(&convert_argument);
-  __ push(function);  // Preserve the function.
-  __ IncrementCounter(counters->string_ctor_conversions(), 1, a3, a4);
+  // 6. Fallback to the runtime to create new object.
+  __ bind(&new_object);
   {
     FrameScope scope(masm, StackFrame::INTERNAL);
-    __ push(a0);
-    __ InvokeBuiltin(Builtins::TO_STRING, CALL_FUNCTION);
+    __ Push(a0, a1, a3);  // first argument, constructor, new target
+    __ CallRuntime(Runtime::kNewObject);
+    __ Pop(a0);
   }
-  __ pop(function);
-  __ mov(argument, v0);
-  __ Branch(&argument_is_string);
+  __ Ret(USE_DELAY_SLOT);
+  __ sd(a0, FieldMemOperand(v0, JSValue::kValueOffset));  // In delay slot.
+}
 
-  // Load the empty string into a2, remove the receiver from the
-  // stack, and jump back to the case where the argument is a string.
+
+// static
+void Builtins::Generate_StringConstructor(MacroAssembler* masm) {
+  // ----------- S t a t e -------------
+  //  -- a0                     : number of arguments
+  //  -- a1                     : constructor function
+  //  -- ra                     : return address
+  //  -- sp[(argc - n - 1) * 8] : arg[n] (zero based)
+  //  -- sp[argc * 8]           : receiver
+  // -----------------------------------
+
+  // 1. Load the first argument into a0 and get rid of the rest (including the
+  // receiver).
+  Label no_arguments;
+  {
+    __ Branch(USE_DELAY_SLOT, &no_arguments, eq, a0, Operand(zero_reg));
+    __ Dsubu(a0, a0, Operand(1));
+    __ dsll(a0, a0, kPointerSizeLog2);
+    __ Daddu(sp, a0, sp);
+    __ ld(a0, MemOperand(sp));
+    __ Drop(2);
+  }
+
+  // 2a. At least one argument, return a0 if it's a string, otherwise
+  // dispatch to appropriate conversion.
+  Label to_string, symbol_descriptive_string;
+  {
+    __ JumpIfSmi(a0, &to_string);
+    __ GetObjectType(a0, a1, a1);
+    STATIC_ASSERT(FIRST_NONSTRING_TYPE == SYMBOL_TYPE);
+    __ Subu(a1, a1, Operand(FIRST_NONSTRING_TYPE));
+    __ Branch(&symbol_descriptive_string, eq, a1, Operand(zero_reg));
+    __ Branch(&to_string, gt, a1, Operand(zero_reg));
+    __ Ret(USE_DELAY_SLOT);
+    __ mov(v0, a0);
+  }
+
+  // 2b. No arguments, return the empty string (and pop the receiver).
   __ bind(&no_arguments);
-  __ LoadRoot(argument, Heap::kempty_stringRootIndex);
-  __ Drop(1);
-  __ Branch(&argument_is_string);
+  {
+    __ LoadRoot(v0, Heap::kempty_stringRootIndex);
+    __ DropAndRet(1);
+  }
 
-  // At this point the argument is already a string. Call runtime to
-  // create a string wrapper.
-  __ bind(&gc_required);
-  __ IncrementCounter(counters->string_ctor_gc_required(), 1, a3, a4);
+  // 3a. Convert a0 to a string.
+  __ bind(&to_string);
+  {
+    ToStringStub stub(masm->isolate());
+    __ TailCallStub(&stub);
+  }
+
+  // 3b. Convert symbol in a0 to a string.
+  __ bind(&symbol_descriptive_string);
+  {
+    __ Push(a0);
+    __ TailCallRuntime(Runtime::kSymbolDescriptiveString);
+  }
+}
+
+
+void Builtins::Generate_StringConstructor_ConstructStub(MacroAssembler* masm) {
+  // ----------- S t a t e -------------
+  //  -- a0                     : number of arguments
+  //  -- a1                     : constructor function
+  //  -- a3                     : new target
+  //  -- ra                     : return address
+  //  -- sp[(argc - n - 1) * 8] : arg[n] (zero based)
+  //  -- sp[argc * 8]           : receiver
+  // -----------------------------------
+
+  // 1. Make sure we operate in the context of the called function.
+  __ ld(cp, FieldMemOperand(a1, JSFunction::kContextOffset));
+
+  // 2. Load the first argument into a0 and get rid of the rest (including the
+  // receiver).
+  {
+    Label no_arguments, done;
+    __ Branch(USE_DELAY_SLOT, &no_arguments, eq, a0, Operand(zero_reg));
+    __ Dsubu(a0, a0, Operand(1));
+    __ dsll(a0, a0, kPointerSizeLog2);
+    __ Daddu(sp, a0, sp);
+    __ ld(a0, MemOperand(sp));
+    __ Drop(2);
+    __ jmp(&done);
+    __ bind(&no_arguments);
+    __ LoadRoot(a0, Heap::kempty_stringRootIndex);
+    __ Drop(1);
+    __ bind(&done);
+  }
+
+  // 3. Make sure a0 is a string.
+  {
+    Label convert, done_convert;
+    __ JumpIfSmi(a0, &convert);
+    __ GetObjectType(a0, a2, a2);
+    __ And(t0, a2, Operand(kIsNotStringMask));
+    __ Branch(&done_convert, eq, t0, Operand(zero_reg));
+    __ bind(&convert);
+    {
+      FrameScope scope(masm, StackFrame::INTERNAL);
+      ToStringStub stub(masm->isolate());
+      __ Push(a1, a3);
+      __ CallStub(&stub);
+      __ Move(a0, v0);
+      __ Pop(a1, a3);
+    }
+    __ bind(&done_convert);
+  }
+
+  // 4. Check if new target and constructor differ.
+  Label new_object;
+  __ Branch(&new_object, ne, a1, Operand(a3));
+
+  // 5. Allocate a JSValue wrapper for the string.
+  __ AllocateJSValue(v0, a1, a0, a2, t0, &new_object);
+  __ Ret();
+
+  // 6. Fallback to the runtime to create new object.
+  __ bind(&new_object);
   {
     FrameScope scope(masm, StackFrame::INTERNAL);
-    __ push(argument);
-    __ CallRuntime(Runtime::kNewStringWrapper, 1);
+    __ Push(a0, a1, a3);  // first argument, constructor, new target
+    __ CallRuntime(Runtime::kNewObject);
+    __ Pop(a0);
   }
-  __ Ret();
+  __ Ret(USE_DELAY_SLOT);
+  __ sd(a0, FieldMemOperand(v0, JSValue::kValueOffset));  // In delay slot.
 }
 
 
 static void CallRuntimePassFunction(
     MacroAssembler* masm, Runtime::FunctionId function_id) {
+  // ----------- S t a t e -------------
+  //  -- a1 : target function (preserved for callee)
+  //  -- a3 : new target (preserved for callee)
+  // -----------------------------------
+
   FrameScope scope(masm, StackFrame::INTERNAL);
   // Push a copy of the function onto the stack.
-  // Push call kind information and function as parameter to the runtime call.
-  __ Push(a1, a1);
+  // Push a copy of the target function and the new target.
+  __ Push(a1, a3, a1);
 
   __ CallRuntime(function_id, 1);
-  // Restore call kind information and receiver.
-  __ Pop(a1);
+  // Restore target function and new target.
+  __ Pop(a1, a3);
 }
 
 
@@ -316,367 +422,206 @@
 
 static void Generate_JSConstructStubHelper(MacroAssembler* masm,
                                            bool is_api_function,
-                                           bool create_memento) {
+                                           bool create_implicit_receiver) {
   // ----------- S t a t e -------------
   //  -- a0     : number of arguments
   //  -- a1     : constructor function
   //  -- a2     : allocation site or undefined
+  //  -- a3     : new target
   //  -- ra     : return address
   //  -- sp[...]: constructor arguments
   // -----------------------------------
 
-  // Should never create mementos for api functions.
-  DCHECK(!is_api_function || !create_memento);
-
   Isolate* isolate = masm->isolate();
 
-  // ----------- S t a t e -------------
-  //  -- a0     : number of arguments
-  //  -- a1     : constructor function
-  //  -- ra     : return address
-  //  -- sp[...]: constructor arguments
-  // -----------------------------------
-
   // Enter a construct frame.
   {
     FrameScope scope(masm, StackFrame::CONSTRUCT);
 
-    if (create_memento) {
-      __ AssertUndefinedOrAllocationSite(a2, a3);
-      __ push(a2);
-    }
+    // Preserve the incoming parameters on the stack.
+    __ AssertUndefinedOrAllocationSite(a2, t0);
+    __ SmiTag(a0);
+    __ Push(a2, a0);
 
-    // Preserve the two incoming parameters on the stack.
-    // Tag arguments count.
-    __ dsll32(a0, a0, 0);
-    __ MultiPushReversed(a0.bit() | a1.bit());
+    if (create_implicit_receiver) {
+      // Try to allocate the object without transitioning into C code. If any of
+      // the preconditions is not met, the code bails out to the runtime call.
+      Label rt_call, allocated;
+      if (FLAG_inline_new) {
+        // Verify that the new target is a JSFunction.
+        __ GetObjectType(a3, a5, a4);
+        __ Branch(&rt_call, ne, a4, Operand(JS_FUNCTION_TYPE));
 
-    Label rt_call, allocated;
-    // Try to allocate the object without transitioning into C code. If any of
-    // the preconditions is not met, the code bails out to the runtime call.
-    if (FLAG_inline_new) {
-      Label undo_allocation;
-      ExternalReference debug_step_in_fp =
-          ExternalReference::debug_step_in_fp_address(isolate);
-      __ li(a2, Operand(debug_step_in_fp));
-      __ ld(a2, MemOperand(a2));
-      __ Branch(&rt_call, ne, a2, Operand(zero_reg));
+        // Load the initial map and verify that it is in fact a map.
+        // a3: new target
+        __ ld(a2,
+              FieldMemOperand(a3, JSFunction::kPrototypeOrInitialMapOffset));
+        __ JumpIfSmi(a2, &rt_call);
+        __ GetObjectType(a2, t1, t0);
+        __ Branch(&rt_call, ne, t0, Operand(MAP_TYPE));
 
-      // Load the initial map and verify that it is in fact a map.
-      // a1: constructor function
-      __ ld(a2, FieldMemOperand(a1, JSFunction::kPrototypeOrInitialMapOffset));
-      __ JumpIfSmi(a2, &rt_call);
-      __ GetObjectType(a2, a3, t0);
-      __ Branch(&rt_call, ne, t0, Operand(MAP_TYPE));
+        // Fall back to runtime if the expected base constructor and base
+        // constructor differ.
+        __ ld(a5, FieldMemOperand(a2, Map::kConstructorOrBackPointerOffset));
+        __ Branch(&rt_call, ne, a1, Operand(a5));
 
-      // Check that the constructor is not constructing a JSFunction (see
-      // comments in Runtime_NewObject in runtime.cc). In which case the
-      // initial map's instance type would be JS_FUNCTION_TYPE.
-      // a1: constructor function
-      // a2: initial map
-      __ lbu(a3, FieldMemOperand(a2, Map::kInstanceTypeOffset));
-      __ Branch(&rt_call, eq, a3, Operand(JS_FUNCTION_TYPE));
+        // Check that the constructor is not constructing a JSFunction (see
+        // comments in Runtime_NewObject in runtime.cc). In which case the
+        // initial map's instance type would be JS_FUNCTION_TYPE.
+        // a1: constructor function
+        // a2: initial map
+        __ lbu(t1, FieldMemOperand(a2, Map::kInstanceTypeOffset));
+        __ Branch(&rt_call, eq, t1, Operand(JS_FUNCTION_TYPE));
 
-      if (!is_api_function) {
-        Label allocate;
-        MemOperand bit_field3 = FieldMemOperand(a2, Map::kBitField3Offset);
-        // Check if slack tracking is enabled.
-        __ lwu(a4, bit_field3);
-        __ DecodeField<Map::Counter>(a6, a4);
-        __ Branch(&allocate, lt, a6,
-                  Operand(static_cast<int64_t>(Map::kSlackTrackingCounterEnd)));
-        // Decrease generous allocation count.
-        __ Dsubu(a4, a4, Operand(1 << Map::Counter::kShift));
-        __ Branch(USE_DELAY_SLOT, &allocate, ne, a6,
-                  Operand(Map::kSlackTrackingCounterEnd));
-        __ sw(a4, bit_field3);  // In delay slot.
+        // Now allocate the JSObject on the heap.
+        // a1: constructor function
+        // a2: initial map
+        __ lbu(a4, FieldMemOperand(a2, Map::kInstanceSizeOffset));
+        __ Allocate(a4, t0, a4, t2, &rt_call, SIZE_IN_WORDS);
 
-        __ Push(a1, a2, a1);  // a1 = Constructor.
-        __ CallRuntime(Runtime::kFinalizeInstanceSize, 1);
+        // Allocated the JSObject, now initialize the fields. Map is set to
+        // initial map and properties and elements are set to empty fixed array.
+        // a1: constructor function
+        // a2: initial map
+        // a3: object size
+        // t0: JSObject (not HeapObject tagged - the actual address).
+        // a4: start of next object
+        __ LoadRoot(t2, Heap::kEmptyFixedArrayRootIndex);
+        __ mov(t1, t0);
+        STATIC_ASSERT(0 * kPointerSize == JSObject::kMapOffset);
+        __ sd(a2, MemOperand(t1, JSObject::kMapOffset));
+        STATIC_ASSERT(1 * kPointerSize == JSObject::kPropertiesOffset);
+        __ sd(t2, MemOperand(t1, JSObject::kPropertiesOffset));
+        STATIC_ASSERT(2 * kPointerSize == JSObject::kElementsOffset);
+        __ sd(t2, MemOperand(t1, JSObject::kElementsOffset));
+        STATIC_ASSERT(3 * kPointerSize == JSObject::kHeaderSize);
+        __ Daddu(t1, t1, Operand(3 * kPointerSize));
 
-        __ Pop(a1, a2);
-        // Slack tracking counter is Map::kSlackTrackingCounterEnd after runtime
-        // call.
-        __ li(a6, Map::kSlackTrackingCounterEnd);
+        // Add the object tag to make the JSObject real, so that we can continue
+        // and jump into the continuation code at any time from now on.
+        __ Daddu(t0, t0, Operand(kHeapObjectTag));
 
-        __ bind(&allocate);
-      }
+        // Fill all the in-object properties with appropriate filler.
+        // t0: JSObject (tagged)
+        // t1: First in-object property of JSObject (not tagged)
+        __ LoadRoot(t3, Heap::kUndefinedValueRootIndex);
 
-      // Now allocate the JSObject on the heap.
-      // a1: constructor function
-      // a2: initial map
-      __ lbu(a3, FieldMemOperand(a2, Map::kInstanceSizeOffset));
-      if (create_memento) {
-        __ Daddu(a3, a3, Operand(AllocationMemento::kSize / kPointerSize));
-      }
+        if (!is_api_function) {
+          Label no_inobject_slack_tracking;
 
-      __ Allocate(a3, t0, t1, t2, &rt_call, SIZE_IN_WORDS);
+          MemOperand bit_field3 = FieldMemOperand(a2, Map::kBitField3Offset);
+          // Check if slack tracking is enabled.
+          __ lwu(t2, bit_field3);
+          __ DecodeField<Map::ConstructionCounter>(a6, t2);
+          // a6: slack tracking counter
+          __ Branch(&no_inobject_slack_tracking, lt, a6,
+                    Operand(Map::kSlackTrackingCounterEnd));
+          // Decrease generous allocation count.
+          __ Dsubu(t2, t2, Operand(1 << Map::ConstructionCounter::kShift));
+          __ sw(t2, bit_field3);
 
-      // Allocated the JSObject, now initialize the fields. Map is set to
-      // initial map and properties and elements are set to empty fixed array.
-      // a1: constructor function
-      // a2: initial map
-      // a3: object size (not including memento if create_memento)
-      // t0: JSObject (not tagged)
-      __ LoadRoot(t2, Heap::kEmptyFixedArrayRootIndex);
-      __ mov(t1, t0);
-      __ sd(a2, MemOperand(t1, JSObject::kMapOffset));
-      __ sd(t2, MemOperand(t1, JSObject::kPropertiesOffset));
-      __ sd(t2, MemOperand(t1, JSObject::kElementsOffset));
-      __ Daddu(t1, t1, Operand(3*kPointerSize));
-      DCHECK_EQ(0 * kPointerSize, JSObject::kMapOffset);
-      DCHECK_EQ(1 * kPointerSize, JSObject::kPropertiesOffset);
-      DCHECK_EQ(2 * kPointerSize, JSObject::kElementsOffset);
+          // Allocate object with a slack.
+          __ lbu(a0, FieldMemOperand(a2, Map::kUnusedPropertyFieldsOffset));
+          __ dsll(a0, a0, kPointerSizeLog2);
+          __ dsubu(a0, a4, a0);
+          // a0: offset of first field after pre-allocated fields
+          if (FLAG_debug_code) {
+            __ Assert(le, kUnexpectedNumberOfPreAllocatedPropertyFields, t1,
+                      Operand(a0));
+          }
+          __ InitializeFieldsWithFiller(t1, a0, t3);
 
-      // Fill all the in-object properties with appropriate filler.
-      // a1: constructor function
-      // a2: initial map
-      // a3: object size (in words, including memento if create_memento)
-      // t0: JSObject (not tagged)
-      // t1: First in-object property of JSObject (not tagged)
-      // a6: slack tracking counter (non-API function case)
-      DCHECK_EQ(3 * kPointerSize, JSObject::kHeaderSize);
+          // To allow truncation fill the remaining fields with one pointer
+          // filler map.
+          __ LoadRoot(t3, Heap::kOnePointerFillerMapRootIndex);
+          __ InitializeFieldsWithFiller(t1, a4, t3);
 
-      // Use t3 to hold undefined, which is used in several places below.
-      __ LoadRoot(t3, Heap::kUndefinedValueRootIndex);
+          // a6: slack tracking counter value before decreasing.
+          __ Branch(&allocated, ne, a6, Operand(Map::kSlackTrackingCounterEnd));
 
-      if (!is_api_function) {
-        Label no_inobject_slack_tracking;
+          // Push the constructor, new_target and the object to the stack,
+          // and then the initial map as an argument to the runtime call.
+          __ Push(a1, a3, t0, a2);
+          __ CallRuntime(Runtime::kFinalizeInstanceSize);
+          __ Pop(a1, a3, t0);
 
-        // Check if slack tracking is enabled.
-        __ Branch(&no_inobject_slack_tracking, lt, a6,
-                  Operand(static_cast<int64_t>(Map::kSlackTrackingCounterEnd)));
+          // Continue with JSObject being successfully allocated.
+          // a1: constructor function
+          // a3: new target
+          // t0: JSObject
+          __ jmp(&allocated);
 
-        // Allocate object with a slack.
-        __ lwu(a0, FieldMemOperand(a2, Map::kInstanceSizesOffset));
-        __ Ext(a0, a0, Map::kPreAllocatedPropertyFieldsByte * kBitsPerByte,
-                kBitsPerByte);
-        __ dsll(at, a0, kPointerSizeLog2);
-        __ daddu(a0, t1, at);
-        // a0: offset of first field after pre-allocated fields
-        if (FLAG_debug_code) {
-          __ dsll(at, a3, kPointerSizeLog2);
-          __ Daddu(t2, t0, Operand(at));   // End of object.
-          __ Assert(le, kUnexpectedNumberOfPreAllocatedPropertyFields,
-              a0, Operand(t2));
+          __ bind(&no_inobject_slack_tracking);
         }
-        __ InitializeFieldsWithFiller(t1, a0, t3);
-        // To allow for truncation.
-        __ LoadRoot(t3, Heap::kOnePointerFillerMapRootIndex);
-        // Fill the remaining fields with one pointer filler map.
 
-        __ bind(&no_inobject_slack_tracking);
+        __ InitializeFieldsWithFiller(t1, a4, t3);
+
+        // Continue with JSObject being successfully allocated.
+        // a1: constructor function
+        // a3: new target
+        // t0: JSObject
+        __ jmp(&allocated);
       }
 
-      if (create_memento) {
-        __ Dsubu(a0, a3, Operand(AllocationMemento::kSize / kPointerSize));
-        __ dsll(a0, a0, kPointerSizeLog2);
-        __ Daddu(a0, t0, Operand(a0));  // End of object.
-        __ InitializeFieldsWithFiller(t1, a0, t3);
-
-        // Fill in memento fields.
-        // t1: points to the allocated but uninitialized memento.
-        __ LoadRoot(t3, Heap::kAllocationMementoMapRootIndex);
-        DCHECK_EQ(0 * kPointerSize, AllocationMemento::kMapOffset);
-        __ sd(t3, MemOperand(t1));
-        __ Daddu(t1, t1, kPointerSize);
-        // Load the AllocationSite.
-        __ ld(t3, MemOperand(sp, 2 * kPointerSize));
-        DCHECK_EQ(1 * kPointerSize, AllocationMemento::kAllocationSiteOffset);
-        __ sd(t3, MemOperand(t1));
-        __ Daddu(t1, t1, kPointerSize);
-      } else {
-        __ dsll(at, a3, kPointerSizeLog2);
-        __ Daddu(a0, t0, Operand(at));  // End of object.
-        __ InitializeFieldsWithFiller(t1, a0, t3);
-      }
-
-      // Add the object tag to make the JSObject real, so that we can continue
-      // and jump into the continuation code at any time from now on. Any
-      // failures need to undo the allocation, so that the heap is in a
-      // consistent state and verifiable.
-      __ Daddu(t0, t0, Operand(kHeapObjectTag));
-
-      // Check if a non-empty properties array is needed. Continue with
-      // allocated object if not fall through to runtime call if it is.
+      // Allocate the new receiver object using the runtime call.
       // a1: constructor function
-      // t0: JSObject
-      // t1: start of next object (not tagged)
-      __ lbu(a3, FieldMemOperand(a2, Map::kUnusedPropertyFieldsOffset));
-      // The field instance sizes contains both pre-allocated property fields
-      // and in-object properties.
-      __ lw(a0, FieldMemOperand(a2, Map::kInstanceSizesOffset));
-      __ Ext(t2, a0, Map::kPreAllocatedPropertyFieldsByte * kBitsPerByte,
-             kBitsPerByte);
-      __ Daddu(a3, a3, Operand(t2));
-      __ Ext(t2, a0, Map::kInObjectPropertiesByte * kBitsPerByte,
-              kBitsPerByte);
-      __ dsubu(a3, a3, t2);
+      // a3: new target
+      __ bind(&rt_call);
 
-      // Done if no extra properties are to be allocated.
-      __ Branch(&allocated, eq, a3, Operand(zero_reg));
-      __ Assert(greater_equal, kPropertyAllocationCountFailed,
-          a3, Operand(zero_reg));
+      // Push the constructor and new_target twice, second pair as arguments
+      // to the runtime call.
+      __ Push(a1, a3, a1, a3);  // constructor function, new target
+      __ CallRuntime(Runtime::kNewObject);
+      __ mov(t0, v0);
+      __ Pop(a1, a3);
 
-      // Scale the number of elements by pointer size and add the header for
-      // FixedArrays to the start of the next object calculation from above.
-      // a1: constructor
-      // a3: number of elements in properties array
-      // t0: JSObject
-      // t1: start of next object
-      __ Daddu(a0, a3, Operand(FixedArray::kHeaderSize / kPointerSize));
-      __ Allocate(
-          a0,
-          t1,
-          t2,
-          a2,
-          &undo_allocation,
-          static_cast<AllocationFlags>(RESULT_CONTAINS_TOP | SIZE_IN_WORDS));
-
-      // Initialize the FixedArray.
-      // a1: constructor
-      // a3: number of elements in properties array (untagged)
-      // t0: JSObject
-      // t1: start of next object
-      __ LoadRoot(t2, Heap::kFixedArrayMapRootIndex);
-      __ mov(a2, t1);
-      __ sd(t2, MemOperand(a2, JSObject::kMapOffset));
-      // Tag number of elements.
-      __ dsll32(a0, a3, 0);
-      __ sd(a0, MemOperand(a2, FixedArray::kLengthOffset));
-      __ Daddu(a2, a2, Operand(2 * kPointerSize));
-
-      DCHECK_EQ(0 * kPointerSize, JSObject::kMapOffset);
-      DCHECK_EQ(1 * kPointerSize, FixedArray::kLengthOffset);
-
-      // Initialize the fields to undefined.
-      // a1: constructor
-      // a2: First element of FixedArray (not tagged)
-      // a3: number of elements in properties array
-      // t0: JSObject
-      // t1: FixedArray (not tagged)
-      __ dsll(a7, a3, kPointerSizeLog2);
-      __ daddu(t2, a2, a7);  // End of object.
-      DCHECK_EQ(2 * kPointerSize, FixedArray::kHeaderSize);
-      { Label loop, entry;
-        if (!is_api_function || create_memento) {
-          __ LoadRoot(t3, Heap::kUndefinedValueRootIndex);
-        } else if (FLAG_debug_code) {
-          __ LoadRoot(a6, Heap::kUndefinedValueRootIndex);
-          __ Assert(eq, kUndefinedValueNotLoaded, t3, Operand(a6));
-        }
-        __ jmp(&entry);
-        __ bind(&loop);
-        __ sd(t3, MemOperand(a2));
-        __ daddiu(a2, a2, kPointerSize);
-        __ bind(&entry);
-        __ Branch(&loop, less, a2, Operand(t2));
-      }
-
-      // Store the initialized FixedArray into the properties field of
-      // the JSObject.
+      // Receiver for constructor call allocated.
       // a1: constructor function
+      // a3: new target
       // t0: JSObject
-      // t1: FixedArray (not tagged)
-      __ Daddu(t1, t1, Operand(kHeapObjectTag));  // Add the heap tag.
-      __ sd(t1, FieldMemOperand(t0, JSObject::kPropertiesOffset));
+      __ bind(&allocated);
 
-      // Continue with JSObject being successfully allocated.
-      // a1: constructor function
-      // a4: JSObject
-      __ jmp(&allocated);
-
-      // Undo the setting of the new top so that the heap is verifiable. For
-      // example, the map's unused properties potentially do not match the
-      // allocated objects unused properties.
-      // t0: JSObject (previous new top)
-      __ bind(&undo_allocation);
-      __ UndoAllocationInNewSpace(t0, t1);
+      __ ld(a0, MemOperand(sp));
     }
+    __ SmiUntag(a0);
 
-    // Allocate the new receiver object using the runtime call.
-    // a1: constructor function
-    __ bind(&rt_call);
-    if (create_memento) {
-      // Get the cell or allocation site.
-      __ ld(a2, MemOperand(sp, 2 * kPointerSize));
-      __ push(a2);
-    }
-
-    __ push(a1);  // Argument for Runtime_NewObject.
-    if (create_memento) {
-      __ CallRuntime(Runtime::kNewObjectWithAllocationSite, 2);
+    if (create_implicit_receiver) {
+      // Push the allocated receiver to the stack. We need two copies
+      // because we may have to return the original one and the calling
+      // conventions dictate that the called function pops the receiver.
+      __ Push(t0, t0);
     } else {
-      __ CallRuntime(Runtime::kNewObject, 1);
+      __ PushRoot(Heap::kTheHoleValueRootIndex);
     }
-    __ mov(t0, v0);
-
-    // If we ended up using the runtime, and we want a memento, then the
-    // runtime call made it for us, and we shouldn't do create count
-    // increment.
-    Label count_incremented;
-    if (create_memento) {
-      __ jmp(&count_incremented);
-    }
-
-    // Receiver for constructor call allocated.
-    // t0: JSObject
-    __ bind(&allocated);
-
-    if (create_memento) {
-      __ ld(a2, MemOperand(sp, kPointerSize * 2));
-      __ LoadRoot(t1, Heap::kUndefinedValueRootIndex);
-      __ Branch(&count_incremented, eq, a2, Operand(t1));
-      // a2 is an AllocationSite. We are creating a memento from it, so we
-      // need to increment the memento create count.
-      __ ld(a3, FieldMemOperand(a2,
-                                AllocationSite::kPretenureCreateCountOffset));
-      __ Daddu(a3, a3, Operand(Smi::FromInt(1)));
-      __ sd(a3, FieldMemOperand(a2,
-                                AllocationSite::kPretenureCreateCountOffset));
-      __ bind(&count_incremented);
-    }
-
-    __ Push(t0, t0);
-
-    // Reload the number of arguments from the stack.
-    // sp[0]: receiver
-    // sp[1]: receiver
-    // sp[2]: constructor function
-    // sp[3]: number of arguments (smi-tagged)
-    __ ld(a1, MemOperand(sp, 2 * kPointerSize));
-    __ ld(a3, MemOperand(sp, 3 * kPointerSize));
 
     // Set up pointer to last argument.
     __ Daddu(a2, fp, Operand(StandardFrameConstants::kCallerSPOffset));
 
-    // Set up number of arguments for function call below.
-    __ SmiUntag(a0, a3);
-
     // Copy arguments and receiver to the expression stack.
     // a0: number of arguments
     // a1: constructor function
     // a2: address of last argument (caller sp)
-    // a3: number of arguments (smi-tagged)
+    // a3: new target
+    // t0: number of arguments (smi-tagged)
     // sp[0]: receiver
     // sp[1]: receiver
-    // sp[2]: constructor function
-    // sp[3]: number of arguments (smi-tagged)
+    // sp[2]: number of arguments (smi-tagged)
     Label loop, entry;
-    __ SmiUntag(a3);
+    __ mov(t0, a0);
     __ jmp(&entry);
     __ bind(&loop);
-    __ dsll(a4, a3, kPointerSizeLog2);
+    __ dsll(a4, t0, kPointerSizeLog2);
     __ Daddu(a4, a2, Operand(a4));
     __ ld(a5, MemOperand(a4));
     __ push(a5);
     __ bind(&entry);
-    __ Daddu(a3, a3, Operand(-1));
-    __ Branch(&loop, greater_equal, a3, Operand(zero_reg));
+    __ Daddu(t0, t0, Operand(-1));
+    __ Branch(&loop, greater_equal, t0, Operand(zero_reg));
 
     // Call the function.
     // a0: number of arguments
     // a1: constructor function
+    // a3: new target
     if (is_api_function) {
       __ ld(cp, FieldMemOperand(a1, JSFunction::kContextOffset));
       Handle<Code> code =
@@ -684,47 +629,50 @@
       __ Call(code, RelocInfo::CODE_TARGET);
     } else {
       ParameterCount actual(a0);
-      __ InvokeFunction(a1, actual, CALL_FUNCTION, NullCallWrapper());
+      __ InvokeFunction(a1, a3, actual, CALL_FUNCTION,
+                        CheckDebugStepCallWrapper());
     }
 
     // Store offset of return address for deoptimizer.
-    if (!is_api_function) {
+    if (create_implicit_receiver && !is_api_function) {
       masm->isolate()->heap()->SetConstructStubDeoptPCOffset(masm->pc_offset());
     }
 
     // Restore context from the frame.
     __ ld(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
 
-    // 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 (create_implicit_receiver) {
+      // If the result is an object (in the ECMA sense), we should get rid
+      // of the receiver and use the result; see ECMA-262 section 13.2.2-7
+      // on page 74.
+      Label use_receiver, exit;
 
-    // If the result is a smi, it is *not* an object in the ECMA sense.
-    // v0: result
-    // sp[0]: receiver (newly allocated object)
-    // sp[1]: constructor function
-    // sp[2]: number of arguments (smi-tagged)
-    __ JumpIfSmi(v0, &use_receiver);
+      // If the result is a smi, it is *not* an object in the ECMA sense.
+      // v0: result
+      // sp[0]: receiver (newly allocated object)
+      // sp[1]: number of arguments (smi-tagged)
+      __ JumpIfSmi(v0, &use_receiver);
 
-    // If the type of the result (stored in its map) is less than
-    // FIRST_SPEC_OBJECT_TYPE, it is not an object in the ECMA sense.
-    __ GetObjectType(v0, a1, a3);
-    __ Branch(&exit, greater_equal, a3, Operand(FIRST_SPEC_OBJECT_TYPE));
+      // If the type of the result (stored in its map) is less than
+      // FIRST_JS_RECEIVER_TYPE, it is not an object in the ECMA sense.
+      __ GetObjectType(v0, a1, a3);
+      __ Branch(&exit, greater_equal, a3, Operand(FIRST_JS_RECEIVER_TYPE));
 
-    // Throw away the result of the constructor invocation and use the
-    // on-stack receiver as the result.
-    __ bind(&use_receiver);
-    __ ld(v0, MemOperand(sp));
+      // Throw away the result of the constructor invocation and use the
+      // on-stack receiver as the result.
+      __ bind(&use_receiver);
+      __ ld(v0, MemOperand(sp));
 
-    // Remove receiver from the stack, remove caller arguments, and
-    // return.
-    __ bind(&exit);
-    // v0: result
-    // sp[0]: receiver (newly allocated object)
-    // sp[1]: constructor function
-    // sp[2]: number of arguments (smi-tagged)
-    __ ld(a1, MemOperand(sp, 2 * kPointerSize));
+      // Remove receiver from the stack, remove caller arguments, and
+      // return.
+      __ bind(&exit);
+      // v0: result
+      // sp[0]: receiver (newly allocated object)
+      // sp[1]: number of arguments (smi-tagged)
+      __ ld(a1, MemOperand(sp, 1 * kPointerSize));
+    } else {
+      __ ld(a1, MemOperand(sp));
+    }
 
     // Leave construct frame.
   }
@@ -732,18 +680,62 @@
   __ SmiScale(a4, a1, kPointerSizeLog2);
   __ Daddu(sp, sp, a4);
   __ Daddu(sp, sp, kPointerSize);
-  __ IncrementCounter(isolate->counters()->constructed_objects(), 1, a1, a2);
+  if (create_implicit_receiver) {
+    __ IncrementCounter(isolate->counters()->constructed_objects(), 1, a1, a2);
+  }
   __ Ret();
 }
 
 
 void Builtins::Generate_JSConstructStubGeneric(MacroAssembler* masm) {
-  Generate_JSConstructStubHelper(masm, false, FLAG_pretenuring_call_new);
+  Generate_JSConstructStubHelper(masm, false, true);
 }
 
 
 void Builtins::Generate_JSConstructStubApi(MacroAssembler* masm) {
-  Generate_JSConstructStubHelper(masm, true, false);
+  Generate_JSConstructStubHelper(masm, true, true);
+}
+
+
+void Builtins::Generate_JSBuiltinsConstructStub(MacroAssembler* masm) {
+  Generate_JSConstructStubHelper(masm, false, false);
+}
+
+
+void Builtins::Generate_ConstructedNonConstructable(MacroAssembler* masm) {
+  FrameScope scope(masm, StackFrame::INTERNAL);
+  __ Push(a1);
+  __ CallRuntime(Runtime::kThrowConstructedNonConstructable);
+}
+
+
+enum IsTagged { kArgcIsSmiTagged, kArgcIsUntaggedInt };
+
+
+// Clobbers a2; preserves all other registers.
+static void Generate_CheckStackOverflow(MacroAssembler* masm, Register argc,
+                                        IsTagged argc_is_tagged) {
+  // Check the stack for overflow. We are not trying to catch
+  // interruptions (e.g. debug break and preemption) here, so the "real stack
+  // limit" is checked.
+  Label okay;
+  __ LoadRoot(a2, Heap::kRealStackLimitRootIndex);
+  // Make a2 the space we have left. The stack might already be overflowed
+  // here which will cause r2 to become negative.
+  __ dsubu(a2, sp, a2);
+  // Check if the arguments will overflow the stack.
+  if (argc_is_tagged == kArgcIsSmiTagged) {
+    __ SmiScale(a7, v0, kPointerSizeLog2);
+  } else {
+    DCHECK(argc_is_tagged == kArgcIsUntaggedInt);
+    __ dsll(a7, argc, kPointerSizeLog2);
+  }
+  __ Branch(&okay, gt, a2, Operand(a7));  // Signed comparison.
+
+  // Out of stack space.
+  __ CallRuntime(Runtime::kThrowStackOverflow);
+
+  __ bind(&okay);
 }
 
 
@@ -752,7 +744,7 @@
   // Called from JSEntryStub::GenerateBody
 
   // ----------- S t a t e -------------
-  //  -- a0: code entry
+  //  -- a0: new.target
   //  -- a1: function
   //  -- a2: receiver_pointer
   //  -- a3: argc
@@ -766,12 +758,22 @@
   {
     FrameScope scope(masm, StackFrame::INTERNAL);
 
-    // Set up the context from the function argument.
-    __ ld(cp, FieldMemOperand(a1, JSFunction::kContextOffset));
+    // Setup the context (we need to use the caller context from the isolate).
+    ExternalReference context_address(Isolate::kContextAddress,
+                                      masm->isolate());
+    __ li(cp, Operand(context_address));
+    __ ld(cp, MemOperand(cp));
 
     // Push the function and the receiver onto the stack.
     __ Push(a1, a2);
 
+    // Check if we have enough stack space to push all arguments.
+    // Clobbers a2.
+    Generate_CheckStackOverflow(masm, a3, kArgcIsUntaggedInt);
+
+    // Remember new.target.
+    __ mov(a5, a0);
+
     // Copy arguments to the stack in a loop.
     // a3: argc
     // s0: argv, i.e. points to first arg
@@ -789,6 +791,10 @@
     __ bind(&entry);
     __ Branch(&loop, ne, s0, Operand(a6));
 
+    // Setup new.target and argc.
+    __ mov(a0, a3);
+    __ mov(a3, a5);
+
     // Initialize all JavaScript callee-saved registers, since they will be seen
     // by the garbage collector as part of handlers.
     __ LoadRoot(a4, Heap::kUndefinedValueRootIndex);
@@ -800,17 +806,11 @@
     // s6 holds the root address. Do not clobber.
     // s7 is cp. Do not init.
 
-    // Invoke the code and pass argc as a0.
-    __ mov(a0, a3);
-    if (is_construct) {
-      // No type feedback cell is available
-      __ LoadRoot(a2, Heap::kUndefinedValueRootIndex);
-      CallConstructStub stub(masm->isolate(), NO_CALL_CONSTRUCTOR_FLAGS);
-      __ CallStub(&stub);
-    } else {
-      ParameterCount actual(a0);
-      __ InvokeFunction(a1, actual, CALL_FUNCTION, NullCallWrapper());
-    }
+    // Invoke the code.
+    Handle<Code> builtin = is_construct
+                               ? masm->isolate()->builtins()->Construct()
+                               : masm->isolate()->builtins()->Call();
+    __ Call(builtin, RelocInfo::CODE_TARGET);
 
     // Leave internal frame.
   }
@@ -828,34 +828,304 @@
 }
 
 
+// Generate code for entering a JS function with the interpreter.
+// On entry to the function the receiver and arguments have been pushed on the
+// stack left to right.  The actual argument count matches the formal parameter
+// count expected by the function.
+//
+// The live registers are:
+//   o a1: the JS function object being called.
+//   o a3: the new target
+//   o cp: our context
+//   o fp: the caller's frame pointer
+//   o sp: stack pointer
+//   o ra: return address
+//
+// The function builds a JS frame. Please see JavaScriptFrameConstants in
+// frames-mips.h for its layout.
+// TODO(rmcilroy): We will need to include the current bytecode pointer in the
+// frame.
+void Builtins::Generate_InterpreterEntryTrampoline(MacroAssembler* 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);
+
+  __ Push(ra, fp, cp, a1);
+  __ Daddu(fp, sp, Operand(StandardFrameConstants::kFixedFrameSizeFromFp));
+  __ Push(a3);
+
+  // Push zero for bytecode array offset.
+  __ Push(zero_reg);
+
+  // Get the bytecode array from the function object and load the pointer to the
+  // first entry into kInterpreterBytecodeRegister.
+  __ ld(a0, FieldMemOperand(a1, JSFunction::kSharedFunctionInfoOffset));
+  __ ld(kInterpreterBytecodeArrayRegister,
+        FieldMemOperand(a0, SharedFunctionInfo::kFunctionDataOffset));
+
+  if (FLAG_debug_code) {
+    // Check function data field is actually a BytecodeArray object.
+    __ SmiTst(kInterpreterBytecodeArrayRegister, a4);
+    __ Assert(ne, kFunctionDataShouldBeBytecodeArrayOnInterpreterEntry, a4,
+              Operand(zero_reg));
+    __ GetObjectType(kInterpreterBytecodeArrayRegister, a4, a4);
+    __ Assert(eq, kFunctionDataShouldBeBytecodeArrayOnInterpreterEntry, a4,
+              Operand(BYTECODE_ARRAY_TYPE));
+  }
+
+  // Allocate the local and temporary register file on the stack.
+  {
+    // Load frame size (word) from the BytecodeArray object.
+    __ lw(a4, FieldMemOperand(kInterpreterBytecodeArrayRegister,
+                              BytecodeArray::kFrameSizeOffset));
+
+    // Do a stack check to ensure we don't go over the limit.
+    Label ok;
+    __ Dsubu(a5, sp, Operand(a4));
+    __ LoadRoot(a2, Heap::kRealStackLimitRootIndex);
+    __ Branch(&ok, hs, a5, Operand(a2));
+    __ CallRuntime(Runtime::kThrowStackOverflow);
+    __ bind(&ok);
+
+    // If ok, push undefined as the initial value for all register file entries.
+    Label loop_header;
+    Label loop_check;
+    __ LoadRoot(a5, Heap::kUndefinedValueRootIndex);
+    __ Branch(&loop_check);
+    __ bind(&loop_header);
+    // TODO(rmcilroy): Consider doing more than one push per loop iteration.
+    __ push(a5);
+    // Continue loop if not done.
+    __ bind(&loop_check);
+    __ Dsubu(a4, a4, Operand(kPointerSize));
+    __ Branch(&loop_header, ge, a4, Operand(zero_reg));
+  }
+
+  // TODO(rmcilroy): List of things not currently dealt with here but done in
+  // fullcodegen's prologue:
+  //  - Support profiler (specifically profiling_counter).
+  //  - Call ProfileEntryHookStub when isolate has a function_entry_hook.
+  //  - Allow simulator stop operations if FLAG_stop_at is set.
+  //  - Code aging of the BytecodeArray object.
+
+  // Perform stack guard check.
+  {
+    Label ok;
+    __ LoadRoot(at, Heap::kStackLimitRootIndex);
+    __ Branch(&ok, hs, sp, Operand(at));
+    __ push(kInterpreterBytecodeArrayRegister);
+    __ CallRuntime(Runtime::kStackGuard);
+    __ pop(kInterpreterBytecodeArrayRegister);
+    __ bind(&ok);
+  }
+
+  // Load bytecode offset and dispatch table into registers.
+  __ LoadRoot(kInterpreterAccumulatorRegister, Heap::kUndefinedValueRootIndex);
+  __ Daddu(kInterpreterRegisterFileRegister, fp,
+           Operand(InterpreterFrameConstants::kRegisterFilePointerFromFp));
+  __ li(kInterpreterBytecodeOffsetRegister,
+        Operand(BytecodeArray::kHeaderSize - kHeapObjectTag));
+  __ LoadRoot(kInterpreterDispatchTableRegister,
+              Heap::kInterpreterTableRootIndex);
+  __ Daddu(kInterpreterDispatchTableRegister, kInterpreterDispatchTableRegister,
+           Operand(FixedArray::kHeaderSize - kHeapObjectTag));
+
+  // Dispatch to the first bytecode handler for the function.
+  __ Daddu(a0, kInterpreterBytecodeArrayRegister,
+           kInterpreterBytecodeOffsetRegister);
+  __ lbu(a0, MemOperand(a0));
+  __ dsll(at, a0, kPointerSizeLog2);
+  __ Daddu(at, kInterpreterDispatchTableRegister, at);
+  __ ld(at, MemOperand(at));
+  // TODO(rmcilroy): Make dispatch table point to code entrys to avoid untagging
+  // and header removal.
+  __ Daddu(at, at, Operand(Code::kHeaderSize - kHeapObjectTag));
+  __ Call(at);
+}
+
+
+void Builtins::Generate_InterpreterExitTrampoline(MacroAssembler* masm) {
+  // TODO(rmcilroy): List of things not currently dealt with here but done in
+  // fullcodegen's EmitReturnSequence.
+  //  - Supporting FLAG_trace for Runtime::TraceExit.
+  //  - Support profiler (specifically decrementing profiling_counter
+  //    appropriately and calling out to HandleInterrupts if necessary).
+
+  // The return value is in accumulator, which is already in v0.
+
+  // Leave the frame (also dropping the register file).
+  __ LeaveFrame(StackFrame::JAVA_SCRIPT);
+
+  // Drop receiver + arguments and return.
+  __ lw(at, FieldMemOperand(kInterpreterBytecodeArrayRegister,
+                            BytecodeArray::kParameterSizeOffset));
+  __ Daddu(sp, sp, at);
+  __ Jump(ra);
+}
+
+
+// static
+void Builtins::Generate_InterpreterPushArgsAndCall(MacroAssembler* masm) {
+  // ----------- S t a t e -------------
+  //  -- a0 : the number of arguments (not including the receiver)
+  //  -- a2 : the address of the first argument to be pushed. Subsequent
+  //          arguments should be consecutive above this, in the same order as
+  //          they are to be pushed onto the stack.
+  //  -- a1 : the target to call (can be any Object).
+  // -----------------------------------
+
+  // Find the address of the last argument.
+  __ Daddu(a3, a0, Operand(1));  // Add one for receiver.
+  __ dsll(a3, a3, kPointerSizeLog2);
+  __ Dsubu(a3, a2, Operand(a3));
+
+  // Push the arguments.
+  Label loop_header, loop_check;
+  __ Branch(&loop_check);
+  __ bind(&loop_header);
+  __ ld(t0, MemOperand(a2));
+  __ Daddu(a2, a2, Operand(-kPointerSize));
+  __ push(t0);
+  __ bind(&loop_check);
+  __ Branch(&loop_header, gt, a2, Operand(a3));
+
+  // Call the target.
+  __ Jump(masm->isolate()->builtins()->Call(), RelocInfo::CODE_TARGET);
+}
+
+
+// static
+void Builtins::Generate_InterpreterPushArgsAndConstruct(MacroAssembler* masm) {
+  // ----------- S t a t e -------------
+  // -- a0 : argument count (not including receiver)
+  // -- a3 : new target
+  // -- a1 : constructor to call
+  // -- a2 : address of the first argument
+  // -----------------------------------
+
+  // Find the address of the last argument.
+  __ dsll(t0, a0, kPointerSizeLog2);
+  __ Dsubu(t0, a2, Operand(t0));
+
+  // Push a slot for the receiver.
+  __ push(zero_reg);
+
+  // Push the arguments.
+  Label loop_header, loop_check;
+  __ Branch(&loop_check);
+  __ bind(&loop_header);
+  __ ld(t1, MemOperand(a2));
+  __ Daddu(a2, a2, Operand(-kPointerSize));
+  __ push(t1);
+  __ bind(&loop_check);
+  __ Branch(&loop_header, gt, a2, Operand(t0));
+
+  // Call the constructor with a0, a1, and a3 unmodified.
+  __ Jump(masm->isolate()->builtins()->Construct(), RelocInfo::CODE_TARGET);
+}
+
+
+static void Generate_InterpreterNotifyDeoptimizedHelper(
+    MacroAssembler* masm, Deoptimizer::BailoutType type) {
+  // Enter an internal frame.
+  {
+    FrameScope scope(masm, StackFrame::INTERNAL);
+    __ push(kInterpreterAccumulatorRegister);  // Save accumulator register.
+
+    // Pass the deoptimization type to the runtime system.
+    __ li(a1, Operand(Smi::FromInt(static_cast<int>(type))));
+    __ push(a1);
+    __ CallRuntime(Runtime::kNotifyDeoptimized);
+
+    __ pop(kInterpreterAccumulatorRegister);  // Restore accumulator register.
+    // Tear down internal frame.
+  }
+
+  // Drop state (we don't use this for interpreter deopts).
+  __ Drop(1);
+
+  // Initialize register file register and dispatch table register.
+  __ Daddu(kInterpreterRegisterFileRegister, fp,
+           Operand(InterpreterFrameConstants::kRegisterFilePointerFromFp));
+  __ LoadRoot(kInterpreterDispatchTableRegister,
+              Heap::kInterpreterTableRootIndex);
+  __ Daddu(kInterpreterDispatchTableRegister, kInterpreterDispatchTableRegister,
+           Operand(FixedArray::kHeaderSize - kHeapObjectTag));
+
+  // Get the context from the frame.
+  // TODO(rmcilroy): Update interpreter frame to expect current context at the
+  // context slot instead of the function context.
+  __ ld(kContextRegister,
+        MemOperand(kInterpreterRegisterFileRegister,
+                   InterpreterFrameConstants::kContextFromRegisterPointer));
+
+  // Get the bytecode array pointer from the frame.
+  __ ld(a1,
+        MemOperand(kInterpreterRegisterFileRegister,
+                   InterpreterFrameConstants::kFunctionFromRegisterPointer));
+  __ ld(a1, FieldMemOperand(a1, JSFunction::kSharedFunctionInfoOffset));
+  __ ld(kInterpreterBytecodeArrayRegister,
+        FieldMemOperand(a1, SharedFunctionInfo::kFunctionDataOffset));
+
+  if (FLAG_debug_code) {
+    // Check function data field is actually a BytecodeArray object.
+    __ SmiTst(kInterpreterBytecodeArrayRegister, at);
+    __ Assert(ne, kFunctionDataShouldBeBytecodeArrayOnInterpreterEntry, at,
+              Operand(zero_reg));
+    __ GetObjectType(kInterpreterBytecodeArrayRegister, a1, a1);
+    __ Assert(eq, kFunctionDataShouldBeBytecodeArrayOnInterpreterEntry, a1,
+              Operand(BYTECODE_ARRAY_TYPE));
+  }
+
+  // Get the target bytecode offset from the frame.
+  __ ld(kInterpreterBytecodeOffsetRegister,
+        MemOperand(
+            kInterpreterRegisterFileRegister,
+            InterpreterFrameConstants::kBytecodeOffsetFromRegisterPointer));
+  __ SmiUntag(kInterpreterBytecodeOffsetRegister);
+
+  // Dispatch to the target bytecode.
+  __ Daddu(a1, kInterpreterBytecodeArrayRegister,
+           kInterpreterBytecodeOffsetRegister);
+  __ lbu(a1, MemOperand(a1));
+  __ dsll(a1, a1, kPointerSizeLog2);
+  __ Daddu(a1, kInterpreterDispatchTableRegister, a1);
+  __ ld(a1, MemOperand(a1));
+  __ Daddu(a1, a1, Operand(Code::kHeaderSize - kHeapObjectTag));
+  __ Jump(a1);
+}
+
+
+void Builtins::Generate_InterpreterNotifyDeoptimized(MacroAssembler* masm) {
+  Generate_InterpreterNotifyDeoptimizedHelper(masm, Deoptimizer::EAGER);
+}
+
+
+void Builtins::Generate_InterpreterNotifySoftDeoptimized(MacroAssembler* masm) {
+  Generate_InterpreterNotifyDeoptimizedHelper(masm, Deoptimizer::SOFT);
+}
+
+
+void Builtins::Generate_InterpreterNotifyLazyDeoptimized(MacroAssembler* masm) {
+  Generate_InterpreterNotifyDeoptimizedHelper(masm, Deoptimizer::LAZY);
+}
+
+
 void Builtins::Generate_CompileLazy(MacroAssembler* masm) {
   CallRuntimePassFunction(masm, Runtime::kCompileLazy);
   GenerateTailCallToReturnedCode(masm);
 }
 
 
-static void CallCompileOptimized(MacroAssembler* masm, bool concurrent) {
-  FrameScope scope(masm, StackFrame::INTERNAL);
-  // Push a copy of the function onto the stack.
-  // Push function as parameter to the runtime call.
-  __ Push(a1, a1);
-  // Whether to compile in a background thread.
-  __ Push(masm->isolate()->factory()->ToBoolean(concurrent));
-
-  __ CallRuntime(Runtime::kCompileOptimized, 2);
-  // Restore receiver.
-  __ Pop(a1);
-}
-
-
 void Builtins::Generate_CompileOptimized(MacroAssembler* masm) {
-  CallCompileOptimized(masm, false);
+  CallRuntimePassFunction(masm, Runtime::kCompileOptimized_NotConcurrent);
   GenerateTailCallToReturnedCode(masm);
 }
 
 
 void Builtins::Generate_CompileOptimizedConcurrent(MacroAssembler* masm) {
-  CallCompileOptimized(masm, true);
+  CallRuntimePassFunction(masm, Runtime::kCompileOptimized_Concurrent);
   GenerateTailCallToReturnedCode(masm);
 }
 
@@ -875,8 +1145,9 @@
   // the runtime:
   //   a0 - contains return address (beginning of patch sequence)
   //   a1 - isolate
+  //   a3 - new target
   RegList saved_regs =
-      (a0.bit() | a1.bit() | ra.bit() | fp.bit()) & ~sp.bit();
+      (a0.bit() | a1.bit() | a3.bit() | ra.bit() | fp.bit()) & ~sp.bit();
   FrameScope scope(masm, StackFrame::MANUAL);
   __ MultiPush(saved_regs);
   __ PrepareCallCFunction(2, 0, a2);
@@ -914,8 +1185,9 @@
   // the runtime:
   //   a0 - contains return address (beginning of patch sequence)
   //   a1 - isolate
+  //   a3 - new target
   RegList saved_regs =
-      (a0.bit() | a1.bit() | ra.bit() | fp.bit()) & ~sp.bit();
+      (a0.bit() | a1.bit() | a3.bit() | ra.bit() | fp.bit()) & ~sp.bit();
   FrameScope scope(masm, StackFrame::MANUAL);
   __ MultiPush(saved_regs);
   __ PrepareCallCFunction(2, 0, a2);
@@ -940,6 +1212,11 @@
 }
 
 
+void Builtins::Generate_MarkCodeAsToBeExecutedOnce(MacroAssembler* masm) {
+  Generate_MarkCodeAsExecutedOnce(masm);
+}
+
+
 static void Generate_NotifyStubFailureHelper(MacroAssembler* masm,
                                              SaveFPRegsMode save_doubles) {
   {
@@ -950,7 +1227,7 @@
     // registers.
     __ MultiPush(kJSCallerSaved | kCalleeSaved);
     // Pass the function and deoptimization type to the runtime system.
-    __ CallRuntime(Runtime::kNotifyStubFailure, 0, save_doubles);
+    __ CallRuntime(Runtime::kNotifyStubFailure, save_doubles);
     __ MultiPop(kJSCallerSaved | kCalleeSaved);
   }
 
@@ -976,7 +1253,7 @@
     // Pass the function and deoptimization type to the runtime system.
     __ li(a0, Operand(Smi::FromInt(static_cast<int>(type))));
     __ push(a0);
-    __ CallRuntime(Runtime::kNotifyDeoptimized, 1);
+    __ CallRuntime(Runtime::kNotifyDeoptimized);
   }
 
   // Get the full codegen state from the stack and untag it -> a6.
@@ -1018,6 +1295,109 @@
 }
 
 
+// Clobbers {t2, t3, a4, a5}.
+static void CompatibleReceiverCheck(MacroAssembler* masm, Register receiver,
+                                    Register function_template_info,
+                                    Label* receiver_check_failed) {
+  Register signature = t2;
+  Register map = t3;
+  Register constructor = a4;
+  Register scratch = a5;
+
+  // If there is no signature, return the holder.
+  __ ld(signature, FieldMemOperand(function_template_info,
+                                   FunctionTemplateInfo::kSignatureOffset));
+  Label receiver_check_passed;
+  __ JumpIfRoot(signature, Heap::kUndefinedValueRootIndex,
+                &receiver_check_passed);
+
+  // Walk the prototype chain.
+  __ ld(map, FieldMemOperand(receiver, HeapObject::kMapOffset));
+  Label prototype_loop_start;
+  __ bind(&prototype_loop_start);
+
+  // Get the constructor, if any.
+  __ GetMapConstructor(constructor, map, scratch, scratch);
+  Label next_prototype;
+  __ Branch(&next_prototype, ne, scratch, Operand(JS_FUNCTION_TYPE));
+  Register type = constructor;
+  __ ld(type,
+        FieldMemOperand(constructor, JSFunction::kSharedFunctionInfoOffset));
+  __ ld(type, FieldMemOperand(type, SharedFunctionInfo::kFunctionDataOffset));
+
+  // Loop through the chain of inheriting function templates.
+  Label function_template_loop;
+  __ bind(&function_template_loop);
+
+  // If the signatures match, we have a compatible receiver.
+  __ Branch(&receiver_check_passed, eq, signature, Operand(type),
+            USE_DELAY_SLOT);
+
+  // If the current type is not a FunctionTemplateInfo, load the next prototype
+  // in the chain.
+  __ JumpIfSmi(type, &next_prototype);
+  __ GetObjectType(type, scratch, scratch);
+  __ Branch(&next_prototype, ne, scratch, Operand(FUNCTION_TEMPLATE_INFO_TYPE));
+
+  // Otherwise load the parent function template and iterate.
+  __ ld(type,
+        FieldMemOperand(type, FunctionTemplateInfo::kParentTemplateOffset));
+  __ Branch(&function_template_loop);
+
+  // Load the next prototype.
+  __ bind(&next_prototype);
+  __ ld(receiver, FieldMemOperand(map, Map::kPrototypeOffset));
+  // End if the prototype is null or not hidden.
+  __ JumpIfRoot(receiver, Heap::kNullValueRootIndex, receiver_check_failed);
+  __ ld(map, FieldMemOperand(receiver, HeapObject::kMapOffset));
+  __ lwu(scratch, FieldMemOperand(map, Map::kBitField3Offset));
+  __ DecodeField<Map::IsHiddenPrototype>(scratch);
+  __ Branch(receiver_check_failed, eq, scratch, Operand(zero_reg));
+  // Iterate.
+  __ Branch(&prototype_loop_start);
+
+  __ bind(&receiver_check_passed);
+}
+
+
+void Builtins::Generate_HandleFastApiCall(MacroAssembler* masm) {
+  // ----------- S t a t e -------------
+  //  -- a0                 : number of arguments excluding receiver
+  //  -- a1                 : callee
+  //  -- ra                 : return address
+  //  -- sp[0]              : last argument
+  //  -- ...
+  //  -- sp[8 * (argc - 1)] : first argument
+  //  -- sp[8 * argc]       : receiver
+  // -----------------------------------
+
+  // Load the FunctionTemplateInfo.
+  __ ld(t1, FieldMemOperand(a1, JSFunction::kSharedFunctionInfoOffset));
+  __ ld(t1, FieldMemOperand(t1, SharedFunctionInfo::kFunctionDataOffset));
+
+  // Do the compatible receiver check
+  Label receiver_check_failed;
+  __ sll(at, a0, kPointerSizeLog2);
+  __ Daddu(t8, sp, at);
+  __ ld(t0, MemOperand(t8));
+  CompatibleReceiverCheck(masm, t0, t1, &receiver_check_failed);
+
+  // Get the callback offset from the FunctionTemplateInfo, and jump to the
+  // beginning of the code.
+  __ ld(t2, FieldMemOperand(t1, FunctionTemplateInfo::kCallCodeOffset));
+  __ ld(t2, FieldMemOperand(t2, CallHandlerInfo::kFastHandlerOffset));
+  __ Daddu(t2, t2, Operand(Code::kHeaderSize - kHeapObjectTag));
+  __ Jump(t2);
+
+  // Compatible receiver check failed: throw an Illegal Invocation exception.
+  __ bind(&receiver_check_failed);
+  // Drop the arguments (including the receiver);
+  __ Daddu(t8, t8, Operand(kPointerSize));
+  __ daddu(sp, t8, zero_reg);
+  __ TailCallRuntime(Runtime::kThrowIllegalInvocation);
+}
+
+
 void Builtins::Generate_OnStackReplacement(MacroAssembler* masm) {
   // Lookup the function in the JavaScript frame.
   __ ld(a0, MemOperand(fp, JavaScriptFrameConstants::kFunctionOffset));
@@ -1025,7 +1405,7 @@
     FrameScope scope(masm, StackFrame::INTERNAL);
     // Pass function as argument.
     __ push(a0);
-    __ CallRuntime(Runtime::kCompileForOnStackReplacement, 1);
+    __ CallRuntime(Runtime::kCompileForOnStackReplacement);
   }
 
   // If the code object is null, just return to the unoptimized code.
@@ -1058,7 +1438,7 @@
   __ Branch(&ok, hs, sp, Operand(at));
   {
     FrameScope scope(masm, StackFrame::INTERNAL);
-    __ CallRuntime(Runtime::kStackGuard, 0);
+    __ CallRuntime(Runtime::kStackGuard);
   }
   __ Jump(masm->isolate()->builtins()->OnStackReplacement(),
           RelocInfo::CODE_TARGET);
@@ -1068,126 +1448,151 @@
 }
 
 
-void Builtins::Generate_FunctionCall(MacroAssembler* masm) {
+// static
+void Builtins::Generate_DatePrototype_GetField(MacroAssembler* masm,
+                                               int field_index) {
+  // ----------- S t a t e -------------
+  //  -- sp[0] : receiver
+  // -----------------------------------
+
+  // 1. Pop receiver into a0 and check that it's actually a JSDate object.
+  Label receiver_not_date;
+  {
+    __ Pop(a0);
+    __ JumpIfSmi(a0, &receiver_not_date);
+    __ GetObjectType(a0, t0, t0);
+    __ Branch(&receiver_not_date, ne, t0, Operand(JS_DATE_TYPE));
+  }
+
+  // 2. Load the specified date field, falling back to the runtime as necessary.
+  if (field_index == JSDate::kDateValue) {
+    __ Ret(USE_DELAY_SLOT);
+    __ ld(v0, FieldMemOperand(a0, JSDate::kValueOffset));  // In delay slot.
+  } else {
+    if (field_index < JSDate::kFirstUncachedField) {
+      Label stamp_mismatch;
+      __ li(a1, Operand(ExternalReference::date_cache_stamp(masm->isolate())));
+      __ ld(a1, MemOperand(a1));
+      __ ld(t0, FieldMemOperand(a0, JSDate::kCacheStampOffset));
+      __ Branch(&stamp_mismatch, ne, t0, Operand(a1));
+      __ Ret(USE_DELAY_SLOT);
+      __ ld(v0, FieldMemOperand(
+                    a0, JSDate::kValueOffset +
+                            field_index * kPointerSize));  // In delay slot.
+      __ bind(&stamp_mismatch);
+    }
+    FrameScope scope(masm, StackFrame::INTERNAL);
+    __ PrepareCallCFunction(2, t0);
+    __ li(a1, Operand(Smi::FromInt(field_index)));
+    __ CallCFunction(
+        ExternalReference::get_date_field_function(masm->isolate()), 2);
+  }
+  __ Ret();
+
+  // 3. Raise a TypeError if the receiver is not a date.
+  __ bind(&receiver_not_date);
+  __ TailCallRuntime(Runtime::kThrowNotDateError);
+}
+
+
+// static
+void Builtins::Generate_FunctionPrototypeApply(MacroAssembler* masm) {
+  // ----------- S t a t e -------------
+  //  -- a0    : argc
+  //  -- sp[0] : argArray
+  //  -- sp[4] : thisArg
+  //  -- sp[8] : receiver
+  // -----------------------------------
+
+  // 1. Load receiver into a1, argArray into a0 (if present), remove all
+  // arguments from the stack (including the receiver), and push thisArg (if
+  // present) instead.
+  {
+    Label no_arg;
+    Register scratch = a4;
+    __ LoadRoot(a2, Heap::kUndefinedValueRootIndex);
+    __ mov(a3, a2);
+    __ dsll(scratch, a0, kPointerSizeLog2);
+    __ Daddu(a0, sp, Operand(scratch));
+    __ ld(a1, MemOperand(a0));  // receiver
+    __ Dsubu(a0, a0, Operand(kPointerSize));
+    __ Branch(&no_arg, lt, a0, Operand(sp));
+    __ ld(a2, MemOperand(a0));  // thisArg
+    __ Dsubu(a0, a0, Operand(kPointerSize));
+    __ Branch(&no_arg, lt, a0, Operand(sp));
+    __ ld(a3, MemOperand(a0));  // argArray
+    __ bind(&no_arg);
+    __ Daddu(sp, sp, Operand(scratch));
+    __ sd(a2, MemOperand(sp));
+    __ mov(a0, a3);
+  }
+
+  // ----------- S t a t e -------------
+  //  -- a0    : argArray
+  //  -- a1    : receiver
+  //  -- sp[0] : thisArg
+  // -----------------------------------
+
+  // 2. Make sure the receiver is actually callable.
+  Label receiver_not_callable;
+  __ JumpIfSmi(a1, &receiver_not_callable);
+  __ ld(a4, FieldMemOperand(a1, HeapObject::kMapOffset));
+  __ lbu(a4, FieldMemOperand(a4, Map::kBitFieldOffset));
+  __ And(a4, a4, Operand(1 << Map::kIsCallable));
+  __ Branch(&receiver_not_callable, eq, a4, Operand(zero_reg));
+
+  // 3. Tail call with no arguments if argArray is null or undefined.
+  Label no_arguments;
+  __ JumpIfRoot(a0, Heap::kNullValueRootIndex, &no_arguments);
+  __ JumpIfRoot(a0, Heap::kUndefinedValueRootIndex, &no_arguments);
+
+  // 4a. Apply the receiver to the given argArray (passing undefined for
+  // new.target).
+  __ LoadRoot(a3, 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);
+  {
+    __ mov(a0, zero_reg);
+    __ Jump(masm->isolate()->builtins()->Call(), RelocInfo::CODE_TARGET);
+  }
+
+  // 4c. The receiver is not callable, throw an appropriate TypeError.
+  __ bind(&receiver_not_callable);
+  {
+    __ sd(a1, MemOperand(sp));
+    __ TailCallRuntime(Runtime::kThrowApplyNonFunction);
+  }
+}
+
+
+// static
+void Builtins::Generate_FunctionPrototypeCall(MacroAssembler* masm) {
   // 1. Make sure we have at least one argument.
   // a0: actual number of arguments
-  { Label done;
+  {
+    Label done;
     __ Branch(&done, ne, a0, Operand(zero_reg));
-    __ LoadRoot(a6, Heap::kUndefinedValueRootIndex);
-    __ push(a6);
+    __ PushRoot(Heap::kUndefinedValueRootIndex);
     __ Daddu(a0, a0, Operand(1));
     __ bind(&done);
   }
 
-  // 2. Get the function to call (passed as receiver) from the stack, check
-  //    if it is a function.
+  // 2. Get the function to call (passed as receiver) from the stack.
   // a0: actual number of arguments
-  Label slow, non_function;
   __ dsll(at, a0, kPointerSizeLog2);
   __ daddu(at, sp, at);
   __ ld(a1, MemOperand(at));
-  __ JumpIfSmi(a1, &non_function);
-  __ GetObjectType(a1, a2, a2);
-  __ Branch(&slow, ne, a2, Operand(JS_FUNCTION_TYPE));
 
-  // 3a. Patch the first argument if necessary when calling a function.
-  // a0: actual number of arguments
-  // a1: function
-  Label shift_arguments;
-  __ li(a4, Operand(0, RelocInfo::NONE32));  // Indicate regular JS_FUNCTION.
-  { Label convert_to_object, use_global_proxy, patch_receiver;
-    // Change context eagerly in case we need the global receiver.
-    __ ld(cp, FieldMemOperand(a1, JSFunction::kContextOffset));
-
-    // Do not transform the receiver for strict mode functions.
-    __ ld(a2, FieldMemOperand(a1, JSFunction::kSharedFunctionInfoOffset));
-    __ lbu(a3, FieldMemOperand(a2, SharedFunctionInfo::kStrictModeByteOffset));
-    __ And(a7, a3, Operand(1 << SharedFunctionInfo::kStrictModeBitWithinByte));
-    __ Branch(&shift_arguments, ne, a7, Operand(zero_reg));
-
-    // Do not transform the receiver for native (Compilerhints already in a3).
-    __ lbu(a3, FieldMemOperand(a2, SharedFunctionInfo::kNativeByteOffset));
-    __ And(a7, a3, Operand(1 << SharedFunctionInfo::kNativeBitWithinByte));
-    __ Branch(&shift_arguments, ne, a7, Operand(zero_reg));
-
-    // Compute the receiver in sloppy mode.
-    // Load first argument in a2. a2 = -kPointerSize(sp + n_args << 2).
-    __ dsll(at, a0, kPointerSizeLog2);
-    __ daddu(a2, sp, at);
-    __ ld(a2, MemOperand(a2, -kPointerSize));
-    // a0: actual number of arguments
-    // a1: function
-    // a2: first argument
-    __ JumpIfSmi(a2, &convert_to_object, a6);
-
-    __ LoadRoot(a3, Heap::kUndefinedValueRootIndex);
-    __ Branch(&use_global_proxy, eq, a2, Operand(a3));
-    __ LoadRoot(a3, Heap::kNullValueRootIndex);
-    __ Branch(&use_global_proxy, eq, a2, Operand(a3));
-
-    STATIC_ASSERT(LAST_SPEC_OBJECT_TYPE == LAST_TYPE);
-    __ GetObjectType(a2, a3, a3);
-    __ Branch(&shift_arguments, ge, a3, Operand(FIRST_SPEC_OBJECT_TYPE));
-
-    __ bind(&convert_to_object);
-    // Enter an internal frame in order to preserve argument count.
-    {
-      FrameScope scope(masm, StackFrame::INTERNAL);
-      __ SmiTag(a0);
-      __ Push(a0, a2);
-      __ InvokeBuiltin(Builtins::TO_OBJECT, CALL_FUNCTION);
-      __ mov(a2, v0);
-
-      __ pop(a0);
-      __ SmiUntag(a0);
-      // Leave internal frame.
-    }
-    // Restore the function to a1, and the flag to a4.
-    __ dsll(at, a0, kPointerSizeLog2);
-    __ daddu(at, sp, at);
-    __ ld(a1, MemOperand(at));
-    __ Branch(USE_DELAY_SLOT, &patch_receiver);
-    __ li(a4, Operand(0, RelocInfo::NONE32));
-
-    __ bind(&use_global_proxy);
-    __ ld(a2, ContextOperand(cp, Context::GLOBAL_OBJECT_INDEX));
-    __ ld(a2, FieldMemOperand(a2, GlobalObject::kGlobalProxyOffset));
-
-    __ bind(&patch_receiver);
-    __ dsll(at, a0, kPointerSizeLog2);
-    __ daddu(a3, sp, at);
-    __ sd(a2, MemOperand(a3, -kPointerSize));
-
-    __ Branch(&shift_arguments);
-  }
-
-  // 3b. Check for function proxy.
-  __ bind(&slow);
-  __ li(a4, Operand(1, RelocInfo::NONE32));  // Indicate function proxy.
-  __ Branch(&shift_arguments, eq, a2, Operand(JS_FUNCTION_PROXY_TYPE));
-
-  __ bind(&non_function);
-  __ li(a4, Operand(2, RelocInfo::NONE32));  // Indicate non-function.
-
-  // 3c. Patch the first argument when calling a non-function.  The
-  //     CALL_NON_FUNCTION builtin expects the non-function callee as
-  //     receiver, so overwrite the first argument which will ultimately
-  //     become the receiver.
-  // a0: actual number of arguments
-  // a1: function
-  // a4: call type (0: JS function, 1: function proxy, 2: non-function)
-  __ dsll(at, a0, kPointerSizeLog2);
-  __ daddu(a2, sp, at);
-  __ sd(a1, MemOperand(a2, -kPointerSize));
-
-  // 4. Shift arguments and return address one slot down on the stack
+  // 3. Shift arguments and return address one slot down on the stack
   //    (overwriting the original receiver).  Adjust argument count to make
   //    the original first argument the new receiver.
   // a0: actual number of arguments
   // a1: function
-  // a4: call type (0: JS function, 1: function proxy, 2: non-function)
-  __ bind(&shift_arguments);
-  { Label loop;
+  {
+    Label loop;
     // Calculate the copy start address (destination). Copy end address is sp.
     __ dsll(at, a0, kPointerSizeLog2);
     __ daddu(a2, sp, at);
@@ -1203,201 +1608,150 @@
     __ Pop();
   }
 
-  // 5a. Call non-function via tail call to CALL_NON_FUNCTION builtin,
-  //     or a function proxy via CALL_FUNCTION_PROXY.
-  // a0: actual number of arguments
-  // a1: function
-  // a4: call type (0: JS function, 1: function proxy, 2: non-function)
-  { Label function, non_proxy;
-    __ Branch(&function, eq, a4, Operand(zero_reg));
-    // Expected number of arguments is 0 for CALL_NON_FUNCTION.
-    __ mov(a2, zero_reg);
-    __ Branch(&non_proxy, ne, a4, Operand(1));
-
-    __ push(a1);  // Re-add proxy object as additional argument.
-    __ Daddu(a0, a0, Operand(1));
-    __ GetBuiltinFunction(a1, Builtins::CALL_FUNCTION_PROXY);
-    __ Jump(masm->isolate()->builtins()->ArgumentsAdaptorTrampoline(),
-            RelocInfo::CODE_TARGET);
-
-    __ bind(&non_proxy);
-    __ GetBuiltinFunction(a1, Builtins::CALL_NON_FUNCTION);
-    __ Jump(masm->isolate()->builtins()->ArgumentsAdaptorTrampoline(),
-            RelocInfo::CODE_TARGET);
-    __ bind(&function);
-  }
-
-  // 5b. Get the code to call from the function and check that the number of
-  //     expected arguments matches what we're providing.  If so, jump
-  //     (tail-call) to the code in register edx without checking arguments.
-  // a0: actual number of arguments
-  // a1: function
-  __ ld(a3, FieldMemOperand(a1, JSFunction::kSharedFunctionInfoOffset));
-  // The argument count is stored as int32_t on 64-bit platforms.
-  // TODO(plind): Smi on 32-bit platforms.
-  __ lw(a2,
-         FieldMemOperand(a3, SharedFunctionInfo::kFormalParameterCountOffset));
-  // Check formal and actual parameter counts.
-  __ Jump(masm->isolate()->builtins()->ArgumentsAdaptorTrampoline(),
-          RelocInfo::CODE_TARGET, ne, a2, Operand(a0));
-
-  __ ld(a3, FieldMemOperand(a1, JSFunction::kCodeEntryOffset));
-  ParameterCount expected(0);
-  __ InvokeCode(a3, expected, expected, JUMP_FUNCTION, NullCallWrapper());
+  // 4. Call the callable.
+  __ Jump(masm->isolate()->builtins()->Call(), RelocInfo::CODE_TARGET);
 }
 
 
-void Builtins::Generate_FunctionApply(MacroAssembler* masm) {
-  const int kIndexOffset    =
-      StandardFrameConstants::kExpressionsOffset - (2 * kPointerSize);
-  const int kLimitOffset    =
-      StandardFrameConstants::kExpressionsOffset - (1 * kPointerSize);
-  const int kArgsOffset     = 2 * kPointerSize;
-  const int kRecvOffset     = 3 * kPointerSize;
-  const int kFunctionOffset = 4 * kPointerSize;
+void Builtins::Generate_ReflectApply(MacroAssembler* masm) {
+  // ----------- S t a t e -------------
+  //  -- a0     : argc
+  //  -- sp[0]  : argumentsList
+  //  -- sp[4]  : thisArgument
+  //  -- sp[8]  : target
+  //  -- sp[12] : receiver
+  // -----------------------------------
 
+  // 1. Load target into a1 (if present), argumentsList into a0 (if present),
+  // remove all arguments from the stack (including the receiver), and push
+  // thisArgument (if present) instead.
   {
-    FrameScope frame_scope(masm, StackFrame::INTERNAL);
-    __ ld(a0, MemOperand(fp, kFunctionOffset));  // Get the function.
-    __ push(a0);
-    __ ld(a0, MemOperand(fp, kArgsOffset));  // Get the args array.
-    __ push(a0);
-    // Returns (in v0) number of arguments to copy to stack as Smi.
-    __ InvokeBuiltin(Builtins::APPLY_PREPARE, CALL_FUNCTION);
-
-    // Check the stack for overflow. We are not trying to catch
-    // interruptions (e.g. debug break and preemption) here, so the "real stack
-    // limit" is checked.
-    Label okay;
-    __ LoadRoot(a2, Heap::kRealStackLimitRootIndex);
-    // Make a2 the space we have left. The stack might already be overflowed
-    // here which will cause a2 to become negative.
-    __ dsubu(a2, sp, a2);
-    // Check if the arguments will overflow the stack.
-    __ SmiScale(a7, v0, kPointerSizeLog2);
-    __ Branch(&okay, gt, a2, Operand(a7));  // Signed comparison.
-
-    // Out of stack space.
-    __ ld(a1, MemOperand(fp, kFunctionOffset));
-    __ Push(a1, v0);
-    __ InvokeBuiltin(Builtins::STACK_OVERFLOW, CALL_FUNCTION);
-    // End of stack check.
-
-    // Push current limit and index.
-    __ bind(&okay);
-    __ mov(a1, zero_reg);
-    __ Push(v0, a1);  // Limit and initial index.
-
-    // Get the receiver.
-    __ ld(a0, MemOperand(fp, kRecvOffset));
-
-    // Check that the function is a JS function (otherwise it must be a proxy).
-    Label push_receiver;
-    __ ld(a1, MemOperand(fp, kFunctionOffset));
-    __ GetObjectType(a1, a2, a2);
-    __ Branch(&push_receiver, ne, a2, Operand(JS_FUNCTION_TYPE));
-
-    // Change context eagerly to get the right global object if necessary.
-    __ ld(cp, FieldMemOperand(a1, JSFunction::kContextOffset));
-    // Load the shared function info while the function is still in a1.
-    __ ld(a2, FieldMemOperand(a1, JSFunction::kSharedFunctionInfoOffset));
-
-    // Compute the receiver.
-    // Do not transform the receiver for strict mode functions.
-    Label call_to_object, use_global_proxy;
-    __ lbu(a7, FieldMemOperand(a2, SharedFunctionInfo::kStrictModeByteOffset));
-    __ And(a7, a7, Operand(1 << SharedFunctionInfo::kStrictModeBitWithinByte));
-    __ Branch(&push_receiver, ne, a7, Operand(zero_reg));
-
-    // Do not transform the receiver for native (Compilerhints already in a2).
-    __ lbu(a7, FieldMemOperand(a2, SharedFunctionInfo::kNativeByteOffset));
-    __ And(a7, a7, Operand(1 << SharedFunctionInfo::kNativeBitWithinByte));
-    __ Branch(&push_receiver, ne, a7, Operand(zero_reg));
-
-    // Compute the receiver in sloppy mode.
-    __ JumpIfSmi(a0, &call_to_object);
-    __ LoadRoot(a1, Heap::kNullValueRootIndex);
-    __ Branch(&use_global_proxy, eq, a0, Operand(a1));
-    __ LoadRoot(a2, Heap::kUndefinedValueRootIndex);
-    __ Branch(&use_global_proxy, eq, a0, Operand(a2));
-
-    // Check if the receiver is already a JavaScript object.
-    // a0: receiver
-    STATIC_ASSERT(LAST_SPEC_OBJECT_TYPE == LAST_TYPE);
-    __ GetObjectType(a0, a1, a1);
-    __ Branch(&push_receiver, ge, a1, Operand(FIRST_SPEC_OBJECT_TYPE));
-
-    // Convert the receiver to a regular object.
-    // a0: receiver
-    __ bind(&call_to_object);
-    __ push(a0);
-    __ InvokeBuiltin(Builtins::TO_OBJECT, CALL_FUNCTION);
-    __ mov(a0, v0);  // Put object in a0 to match other paths to push_receiver.
-    __ Branch(&push_receiver);
-
-    __ bind(&use_global_proxy);
-    __ ld(a0, ContextOperand(cp, Context::GLOBAL_OBJECT_INDEX));
-    __ ld(a0, FieldMemOperand(a0, GlobalObject::kGlobalProxyOffset));
-
-    // Push the receiver.
-    // a0: receiver
-    __ bind(&push_receiver);
-    __ push(a0);
-
-    // Copy all arguments from the array to the stack.
-    Label entry, loop;
-    __ ld(a0, MemOperand(fp, kIndexOffset));
-    __ Branch(&entry);
-
-    // Load the current argument from the arguments array and push it to the
-    // stack.
-    // a0: current argument index
-    __ bind(&loop);
-    __ ld(a1, MemOperand(fp, kArgsOffset));
-    __ Push(a1, a0);
-
-    // Call the runtime to access the property in the arguments array.
-    __ CallRuntime(Runtime::kGetProperty, 2);
-    __ push(v0);
-
-    // Use inline caching to access the arguments.
-    __ ld(a0, MemOperand(fp, kIndexOffset));
-    __ Daddu(a0, a0, Operand(Smi::FromInt(1)));
-    __ sd(a0, MemOperand(fp, kIndexOffset));
-
-    // Test if the copy loop has finished copying all the elements from the
-    // arguments object.
-    __ bind(&entry);
-    __ ld(a1, MemOperand(fp, kLimitOffset));
-    __ Branch(&loop, ne, a0, Operand(a1));
-
-    // Call the function.
-    Label call_proxy;
-    ParameterCount actual(a0);
-    __ SmiUntag(a0);
-    __ ld(a1, MemOperand(fp, kFunctionOffset));
-    __ GetObjectType(a1, a2, a2);
-    __ Branch(&call_proxy, ne, a2, Operand(JS_FUNCTION_TYPE));
-
-    __ InvokeFunction(a1, actual, CALL_FUNCTION, NullCallWrapper());
-
-    frame_scope.GenerateLeaveFrame();
-    __ Ret(USE_DELAY_SLOT);
-    __ Daddu(sp, sp, Operand(3 * kPointerSize));  // In delay slot.
-
-    // Call the function proxy.
-    __ bind(&call_proxy);
-    __ push(a1);  // Add function proxy as last argument.
-    __ Daddu(a0, a0, Operand(1));
-    __ li(a2, Operand(0, RelocInfo::NONE32));
-    __ GetBuiltinFunction(a1, Builtins::CALL_FUNCTION_PROXY);
-    __ Call(masm->isolate()->builtins()->ArgumentsAdaptorTrampoline(),
-            RelocInfo::CODE_TARGET);
-    // Tear down the internal frame and remove function, receiver and args.
+    Label no_arg;
+    Register scratch = a4;
+    __ LoadRoot(a1, Heap::kUndefinedValueRootIndex);
+    __ mov(a2, a1);
+    __ mov(a3, a1);
+    __ dsll(scratch, a0, kPointerSizeLog2);
+    __ mov(a0, scratch);
+    __ Dsubu(a0, a0, Operand(kPointerSize));
+    __ Branch(&no_arg, lt, a0, Operand(zero_reg));
+    __ Daddu(a0, sp, Operand(a0));
+    __ ld(a1, MemOperand(a0));  // target
+    __ Dsubu(a0, a0, Operand(kPointerSize));
+    __ Branch(&no_arg, lt, a0, Operand(sp));
+    __ ld(a2, MemOperand(a0));  // thisArgument
+    __ Dsubu(a0, a0, Operand(kPointerSize));
+    __ Branch(&no_arg, lt, a0, Operand(sp));
+    __ ld(a3, MemOperand(a0));  // argumentsList
+    __ bind(&no_arg);
+    __ Daddu(sp, sp, Operand(scratch));
+    __ sd(a2, MemOperand(sp));
+    __ mov(a0, a3);
   }
 
-  __ Ret(USE_DELAY_SLOT);
-  __ Daddu(sp, sp, Operand(3 * kPointerSize));  // In delay slot.
+  // ----------- S t a t e -------------
+  //  -- a0    : argumentsList
+  //  -- a1    : target
+  //  -- sp[0] : thisArgument
+  // -----------------------------------
+
+  // 2. Make sure the target is actually callable.
+  Label target_not_callable;
+  __ JumpIfSmi(a1, &target_not_callable);
+  __ ld(a4, FieldMemOperand(a1, HeapObject::kMapOffset));
+  __ lbu(a4, FieldMemOperand(a4, Map::kBitFieldOffset));
+  __ And(a4, a4, Operand(1 << Map::kIsCallable));
+  __ Branch(&target_not_callable, eq, a4, Operand(zero_reg));
+
+  // 3a. Apply the target to the given argumentsList (passing undefined for
+  // new.target).
+  __ LoadRoot(a3, Heap::kUndefinedValueRootIndex);
+  __ Jump(masm->isolate()->builtins()->Apply(), RelocInfo::CODE_TARGET);
+
+  // 3b. The target is not callable, throw an appropriate TypeError.
+  __ bind(&target_not_callable);
+  {
+    __ sd(a1, MemOperand(sp));
+    __ TailCallRuntime(Runtime::kThrowApplyNonFunction);
+  }
+}
+
+
+void Builtins::Generate_ReflectConstruct(MacroAssembler* masm) {
+  // ----------- S t a t e -------------
+  //  -- a0     : argc
+  //  -- sp[0]  : new.target (optional)
+  //  -- sp[4]  : argumentsList
+  //  -- sp[8]  : target
+  //  -- sp[12] : receiver
+  // -----------------------------------
+
+  // 1. Load target into a1 (if present), argumentsList into a0 (if present),
+  // new.target into a3 (if present, otherwise use target), remove all
+  // arguments from the stack (including the receiver), and push thisArgument
+  // (if present) instead.
+  {
+    Label no_arg;
+    Register scratch = a4;
+    __ LoadRoot(a1, Heap::kUndefinedValueRootIndex);
+    __ mov(a2, a1);
+    __ dsll(scratch, a0, kPointerSizeLog2);
+    __ Daddu(a0, sp, Operand(scratch));
+    __ sd(a2, MemOperand(a0));  // receiver
+    __ Dsubu(a0, a0, Operand(kPointerSize));
+    __ Branch(&no_arg, lt, a0, Operand(sp));
+    __ ld(a1, MemOperand(a0));  // target
+    __ mov(a3, a1);             // new.target defaults to target
+    __ Dsubu(a0, a0, Operand(kPointerSize));
+    __ Branch(&no_arg, lt, a0, Operand(sp));
+    __ ld(a2, MemOperand(a0));  // argumentsList
+    __ Dsubu(a0, a0, Operand(kPointerSize));
+    __ Branch(&no_arg, lt, a0, Operand(sp));
+    __ ld(a3, MemOperand(a0));  // new.target
+    __ bind(&no_arg);
+    __ Daddu(sp, sp, Operand(scratch));
+    __ mov(a0, a2);
+  }
+
+  // ----------- S t a t e -------------
+  //  -- a0    : argumentsList
+  //  -- a3    : new.target
+  //  -- a1    : target
+  //  -- sp[0] : receiver (undefined)
+  // -----------------------------------
+
+  // 2. Make sure the target is actually a constructor.
+  Label target_not_constructor;
+  __ JumpIfSmi(a1, &target_not_constructor);
+  __ ld(a4, FieldMemOperand(a1, HeapObject::kMapOffset));
+  __ lbu(a4, FieldMemOperand(a4, Map::kBitFieldOffset));
+  __ And(a4, a4, Operand(1 << Map::kIsConstructor));
+  __ Branch(&target_not_constructor, eq, a4, Operand(zero_reg));
+
+  // 3. Make sure the target is actually a constructor.
+  Label new_target_not_constructor;
+  __ JumpIfSmi(a3, &new_target_not_constructor);
+  __ ld(a4, FieldMemOperand(a3, HeapObject::kMapOffset));
+  __ lbu(a4, FieldMemOperand(a4, Map::kBitFieldOffset));
+  __ And(a4, a4, Operand(1 << Map::kIsConstructor));
+  __ Branch(&new_target_not_constructor, eq, a4, Operand(zero_reg));
+
+  // 4a. Construct the target with the given new.target and argumentsList.
+  __ Jump(masm->isolate()->builtins()->Apply(), RelocInfo::CODE_TARGET);
+
+  // 4b. The target is not a constructor, throw an appropriate TypeError.
+  __ bind(&target_not_constructor);
+  {
+    __ sd(a1, MemOperand(sp));
+    __ TailCallRuntime(Runtime::kThrowCalledNonCallable);
+  }
+
+  // 4c. The new.target is not a constructor, throw an appropriate TypeError.
+  __ bind(&new_target_not_constructor);
+  {
+    __ sd(a3, MemOperand(sp));
+    __ TailCallRuntime(Runtime::kThrowCalledNonCallable);
+  }
 }
 
 
@@ -1407,6 +1761,7 @@
   //  -- a0 : actual number of arguments
   //  -- a1 : function (passed through to callee)
   //  -- a2 : expected number of arguments
+  //  -- a3 : new target (passed through to callee)
   // -----------------------------------
   // Check the stack for overflow. We are not trying to catch
   // interruptions (e.g. debug break and preemption) here, so the "real stack
@@ -1449,20 +1804,588 @@
 }
 
 
+// static
+void Builtins::Generate_Apply(MacroAssembler* masm) {
+  // ----------- S t a t e -------------
+  //  -- a0    : argumentsList
+  //  -- a1    : target
+  //  -- a3    : new.target (checked to be constructor or undefined)
+  //  -- sp[0] : thisArgument
+  // -----------------------------------
+
+  // Create the list of arguments from the array-like argumentsList.
+  {
+    Label create_arguments, create_array, create_runtime, done_create;
+    __ JumpIfSmi(a0, &create_runtime);
+
+    // Load the map of argumentsList into a2.
+    __ ld(a2, FieldMemOperand(a0, HeapObject::kMapOffset));
+
+    // Load native context into a4.
+    __ ld(a4, NativeContextMemOperand());
+
+    // Check if argumentsList is an (unmodified) arguments object.
+    __ ld(at, ContextMemOperand(a4, Context::SLOPPY_ARGUMENTS_MAP_INDEX));
+    __ Branch(&create_arguments, eq, a2, Operand(at));
+    __ ld(at, ContextMemOperand(a4, Context::STRICT_ARGUMENTS_MAP_INDEX));
+    __ Branch(&create_arguments, eq, a2, Operand(at));
+
+    // Check if argumentsList is a fast JSArray.
+    __ ld(v0, FieldMemOperand(a2, HeapObject::kMapOffset));
+    __ lbu(v0, FieldMemOperand(v0, Map::kInstanceTypeOffset));
+    __ Branch(&create_array, eq, v0, Operand(JS_ARRAY_TYPE));
+
+    // Ask the runtime to create the list (actually a FixedArray).
+    __ bind(&create_runtime);
+    {
+      FrameScope scope(masm, StackFrame::INTERNAL);
+      __ Push(a1, a3, a0);
+      __ CallRuntime(Runtime::kCreateListFromArrayLike);
+      __ mov(a0, v0);
+      __ Pop(a1, a3);
+      __ ld(a2, FieldMemOperand(v0, FixedArray::kLengthOffset));
+      __ SmiUntag(a2);
+    }
+    __ Branch(&done_create);
+
+    // Try to create the list from an arguments object.
+    __ bind(&create_arguments);
+    __ ld(a2,
+          FieldMemOperand(a0, JSObject::kHeaderSize +
+                                  Heap::kArgumentsLengthIndex * kPointerSize));
+    __ ld(a4, FieldMemOperand(a0, JSObject::kElementsOffset));
+    __ ld(at, FieldMemOperand(a4, FixedArray::kLengthOffset));
+    __ Branch(&create_runtime, ne, a2, Operand(at));
+    __ SmiUntag(a2);
+    __ mov(a0, a4);
+    __ Branch(&done_create);
+
+    // Try to create the list from a JSArray object.
+    __ bind(&create_array);
+    __ ld(a2, FieldMemOperand(a2, Map::kBitField2Offset));
+    __ DecodeField<Map::ElementsKindBits>(a2);
+    STATIC_ASSERT(FAST_SMI_ELEMENTS == 0);
+    STATIC_ASSERT(FAST_HOLEY_SMI_ELEMENTS == 1);
+    STATIC_ASSERT(FAST_ELEMENTS == 2);
+    __ Branch(&create_runtime, hi, a2, Operand(FAST_ELEMENTS));
+    __ Branch(&create_runtime, eq, a2, Operand(FAST_HOLEY_SMI_ELEMENTS));
+    __ ld(a2, FieldMemOperand(a0, JSArray::kLengthOffset));
+    __ ld(a0, FieldMemOperand(a0, JSArray::kElementsOffset));
+    __ SmiUntag(a2);
+
+    __ bind(&done_create);
+  }
+
+  // Check for stack overflow.
+  {
+    // Check the stack for overflow. We are not trying to catch interruptions
+    // (i.e. debug break and preemption) here, so check the "real stack limit".
+    Label done;
+    __ LoadRoot(a4, Heap::kRealStackLimitRootIndex);
+    // Make ip the space we have left. The stack might already be overflowed
+    // here which will cause ip to become negative.
+    __ Dsubu(a4, sp, a4);
+    // Check if the arguments will overflow the stack.
+    __ dsll(at, a2, kPointerSizeLog2);
+    __ Branch(&done, gt, a4, Operand(at));  // Signed comparison.
+    __ TailCallRuntime(Runtime::kThrowStackOverflow);
+    __ bind(&done);
+  }
+
+  // ----------- S t a t e -------------
+  //  -- a1    : target
+  //  -- a0    : args (a FixedArray built from argumentsList)
+  //  -- a2    : len (number of elements to push from args)
+  //  -- a3    : new.target (checked to be constructor or undefined)
+  //  -- sp[0] : thisArgument
+  // -----------------------------------
+
+  // Push arguments onto the stack (thisArgument is already on the stack).
+  {
+    __ mov(a4, zero_reg);
+    Label done, loop;
+    __ bind(&loop);
+    __ Branch(&done, eq, a4, Operand(a2));
+    __ dsll(at, a4, kPointerSizeLog2);
+    __ Daddu(at, a0, at);
+    __ ld(at, FieldMemOperand(at, FixedArray::kHeaderSize));
+    __ Push(at);
+    __ Daddu(a4, a4, Operand(1));
+    __ Branch(&loop);
+    __ bind(&done);
+    __ Move(a0, a4);
+  }
+
+  // Dispatch to Call or Construct depending on whether new.target is undefined.
+  {
+    Label construct;
+    __ LoadRoot(at, Heap::kUndefinedValueRootIndex);
+    __ Branch(&construct, ne, a3, Operand(at));
+    __ Jump(masm->isolate()->builtins()->Call(), RelocInfo::CODE_TARGET);
+    __ bind(&construct);
+    __ Jump(masm->isolate()->builtins()->Construct(), RelocInfo::CODE_TARGET);
+  }
+}
+
+
+// static
+void Builtins::Generate_CallFunction(MacroAssembler* masm,
+                                     ConvertReceiverMode mode) {
+  // ----------- S t a t e -------------
+  //  -- a0 : the number of arguments (not including the receiver)
+  //  -- a1 : the function to call (checked to be a JSFunction)
+  // -----------------------------------
+  __ AssertFunction(a1);
+
+  // See ES6 section 9.2.1 [[Call]] ( thisArgument, argumentsList)
+  // Check that function is not a "classConstructor".
+  Label class_constructor;
+  __ ld(a2, FieldMemOperand(a1, JSFunction::kSharedFunctionInfoOffset));
+  __ lbu(a3, FieldMemOperand(a2, SharedFunctionInfo::kFunctionKindByteOffset));
+  __ And(at, a3, Operand(SharedFunctionInfo::kClassConstructorBitsWithinByte));
+  __ Branch(&class_constructor, ne, at, Operand(zero_reg));
+
+  // Enter the context of the function; ToObject has to run in the function
+  // context, and we also need to take the global proxy from the function
+  // context in case of conversion.
+  STATIC_ASSERT(SharedFunctionInfo::kNativeByteOffset ==
+                SharedFunctionInfo::kStrictModeByteOffset);
+  __ ld(cp, FieldMemOperand(a1, JSFunction::kContextOffset));
+  // We need to convert the receiver for non-native sloppy mode functions.
+  Label done_convert;
+  __ lbu(a3, FieldMemOperand(a2, SharedFunctionInfo::kNativeByteOffset));
+  __ And(at, a3, Operand((1 << SharedFunctionInfo::kNativeBitWithinByte) |
+                         (1 << SharedFunctionInfo::kStrictModeBitWithinByte)));
+  __ Branch(&done_convert, ne, at, Operand(zero_reg));
+  {
+    // ----------- S t a t e -------------
+    //  -- a0 : the number of arguments (not including the receiver)
+    //  -- a1 : the function to call (checked to be a JSFunction)
+    //  -- a2 : the shared function info.
+    //  -- cp : the function context.
+    // -----------------------------------
+
+    if (mode == ConvertReceiverMode::kNullOrUndefined) {
+      // Patch receiver to global proxy.
+      __ LoadGlobalProxy(a3);
+    } else {
+      Label convert_to_object, convert_receiver;
+      __ dsll(at, a0, kPointerSizeLog2);
+      __ daddu(at, sp, at);
+      __ ld(a3, MemOperand(at));
+      __ JumpIfSmi(a3, &convert_to_object);
+      STATIC_ASSERT(LAST_JS_RECEIVER_TYPE == LAST_TYPE);
+      __ GetObjectType(a3, a4, a4);
+      __ Branch(&done_convert, hs, a4, Operand(FIRST_JS_RECEIVER_TYPE));
+      if (mode != ConvertReceiverMode::kNotNullOrUndefined) {
+        Label convert_global_proxy;
+        __ JumpIfRoot(a3, Heap::kUndefinedValueRootIndex,
+                      &convert_global_proxy);
+        __ JumpIfNotRoot(a3, Heap::kNullValueRootIndex, &convert_to_object);
+        __ bind(&convert_global_proxy);
+        {
+          // Patch receiver to global proxy.
+          __ LoadGlobalProxy(a3);
+        }
+        __ Branch(&convert_receiver);
+      }
+      __ bind(&convert_to_object);
+      {
+        // Convert receiver using ToObject.
+        // TODO(bmeurer): Inline the allocation here to avoid building the frame
+        // in the fast case? (fall back to AllocateInNewSpace?)
+        FrameScope scope(masm, StackFrame::INTERNAL);
+        __ SmiTag(a0);
+        __ Push(a0, a1);
+        __ mov(a0, a3);
+        ToObjectStub stub(masm->isolate());
+        __ CallStub(&stub);
+        __ mov(a3, v0);
+        __ Pop(a0, a1);
+        __ SmiUntag(a0);
+      }
+      __ ld(a2, FieldMemOperand(a1, JSFunction::kSharedFunctionInfoOffset));
+      __ bind(&convert_receiver);
+    }
+    __ dsll(at, a0, kPointerSizeLog2);
+    __ daddu(at, sp, at);
+    __ sd(a3, MemOperand(at));
+  }
+  __ bind(&done_convert);
+
+  // ----------- S t a t e -------------
+  //  -- a0 : the number of arguments (not including the receiver)
+  //  -- a1 : the function to call (checked to be a JSFunction)
+  //  -- a2 : the shared function info.
+  //  -- cp : the function context.
+  // -----------------------------------
+
+  __ lw(a2,
+        FieldMemOperand(a2, SharedFunctionInfo::kFormalParameterCountOffset));
+  ParameterCount actual(a0);
+  ParameterCount expected(a2);
+  __ InvokeFunctionCode(a1, no_reg, expected, actual, JUMP_FUNCTION,
+                        CheckDebugStepCallWrapper());
+
+  // The function is a "classConstructor", need to raise an exception.
+  __ bind(&class_constructor);
+  {
+    FrameScope frame(masm, StackFrame::INTERNAL);
+    __ Push(a1);
+    __ CallRuntime(Runtime::kThrowConstructorNonCallableError);
+  }
+}
+
+
+// static
+void Builtins::Generate_CallBoundFunction(MacroAssembler* masm) {
+  // ----------- S t a t e -------------
+  //  -- a0 : the number of arguments (not including the receiver)
+  //  -- a1 : the function to call (checked to be a JSBoundFunction)
+  // -----------------------------------
+  __ AssertBoundFunction(a1);
+
+  // Patch the receiver to [[BoundThis]].
+  {
+    __ ld(at, FieldMemOperand(a1, JSBoundFunction::kBoundThisOffset));
+    __ dsll(a4, a0, kPointerSizeLog2);
+    __ daddu(a4, a4, sp);
+    __ sd(at, MemOperand(a4));
+  }
+
+  // Load [[BoundArguments]] into a2 and length of that into a4.
+  __ ld(a2, FieldMemOperand(a1, JSBoundFunction::kBoundArgumentsOffset));
+  __ ld(a4, FieldMemOperand(a2, FixedArray::kLengthOffset));
+  __ SmiUntag(a4);
+
+  // ----------- S t a t e -------------
+  //  -- a0 : the number of arguments (not including the receiver)
+  //  -- a1 : the function to call (checked to be a JSBoundFunction)
+  //  -- a2 : the [[BoundArguments]] (implemented as FixedArray)
+  //  -- a4 : the number of [[BoundArguments]]
+  // -----------------------------------
+
+  // Reserve stack space for the [[BoundArguments]].
+  {
+    Label done;
+    __ dsll(a5, a4, kPointerSizeLog2);
+    __ Dsubu(sp, sp, Operand(a5));
+    // Check the stack for overflow. We are not trying to catch interruptions
+    // (i.e. debug break and preemption) here, so check the "real stack limit".
+    __ LoadRoot(at, Heap::kRealStackLimitRootIndex);
+    __ Branch(&done, gt, sp, Operand(at));  // Signed comparison.
+    // Restore the stack pointer.
+    __ Daddu(sp, sp, Operand(a5));
+    {
+      FrameScope scope(masm, StackFrame::MANUAL);
+      __ EnterFrame(StackFrame::INTERNAL);
+      __ CallRuntime(Runtime::kThrowStackOverflow);
+    }
+    __ bind(&done);
+  }
+
+  // Relocate arguments down the stack.
+  {
+    Label loop, done_loop;
+    __ mov(a5, zero_reg);
+    __ bind(&loop);
+    __ Branch(&done_loop, gt, a5, Operand(a0));
+    __ dsll(a6, a4, kPointerSizeLog2);
+    __ daddu(a6, a6, sp);
+    __ ld(at, MemOperand(a6));
+    __ dsll(a6, a5, kPointerSizeLog2);
+    __ daddu(a6, a6, sp);
+    __ sd(at, MemOperand(a6));
+    __ Daddu(a4, a4, Operand(1));
+    __ Daddu(a5, a5, Operand(1));
+    __ Branch(&loop);
+    __ bind(&done_loop);
+  }
+
+  // Copy [[BoundArguments]] to the stack (below the arguments).
+  {
+    Label loop, done_loop;
+    __ ld(a4, FieldMemOperand(a2, FixedArray::kLengthOffset));
+    __ SmiUntag(a4);
+    __ Daddu(a2, a2, Operand(FixedArray::kHeaderSize - kHeapObjectTag));
+    __ bind(&loop);
+    __ Dsubu(a4, a4, Operand(1));
+    __ Branch(&done_loop, lt, a4, Operand(zero_reg));
+    __ dsll(a5, a4, kPointerSizeLog2);
+    __ daddu(a5, a5, a2);
+    __ ld(at, MemOperand(a5));
+    __ dsll(a5, a0, kPointerSizeLog2);
+    __ daddu(a5, a5, sp);
+    __ sd(at, MemOperand(a5));
+    __ Daddu(a0, a0, Operand(1));
+    __ Branch(&loop);
+    __ bind(&done_loop);
+  }
+
+  // Call the [[BoundTargetFunction]] via the Call builtin.
+  __ ld(a1, FieldMemOperand(a1, JSBoundFunction::kBoundTargetFunctionOffset));
+  __ li(at, Operand(ExternalReference(Builtins::kCall_ReceiverIsAny,
+                                      masm->isolate())));
+  __ ld(at, MemOperand(at));
+  __ Daddu(at, at, Operand(Code::kHeaderSize - kHeapObjectTag));
+  __ Jump(at);
+}
+
+
+// static
+void Builtins::Generate_Call(MacroAssembler* masm, ConvertReceiverMode mode) {
+  // ----------- S t a t e -------------
+  //  -- a0 : the number of arguments (not including the receiver)
+  //  -- a1 : the target to call (can be any Object).
+  // -----------------------------------
+
+  Label non_callable, non_function, non_smi;
+  __ JumpIfSmi(a1, &non_callable);
+  __ bind(&non_smi);
+  __ GetObjectType(a1, t1, t2);
+  __ Jump(masm->isolate()->builtins()->CallFunction(mode),
+          RelocInfo::CODE_TARGET, eq, t2, Operand(JS_FUNCTION_TYPE));
+  __ Jump(masm->isolate()->builtins()->CallBoundFunction(),
+          RelocInfo::CODE_TARGET, eq, t2, Operand(JS_BOUND_FUNCTION_TYPE));
+  __ Branch(&non_function, ne, t2, Operand(JS_PROXY_TYPE));
+
+  // 1. Runtime fallback for Proxy [[Call]].
+  __ Push(a1);
+  // Increase the arguments size to include the pushed function and the
+  // existing receiver on the stack.
+  __ Daddu(a0, a0, 2);
+  // Tail-call to the runtime.
+  __ JumpToExternalReference(
+      ExternalReference(Runtime::kJSProxyCall, masm->isolate()));
+
+  // 2. Call to something else, which might have a [[Call]] internal method (if
+  // not we raise an exception).
+  __ bind(&non_function);
+  // Check if target has a [[Call]] internal method.
+  __ lbu(t1, FieldMemOperand(t1, Map::kBitFieldOffset));
+  __ And(t1, t1, Operand(1 << Map::kIsCallable));
+  __ Branch(&non_callable, eq, t1, Operand(zero_reg));
+  // Overwrite the original receiver with the (original) target.
+  __ dsll(at, a0, kPointerSizeLog2);
+  __ daddu(at, sp, at);
+  __ sd(a1, MemOperand(at));
+  // Let the "call_as_function_delegate" take care of the rest.
+  __ LoadNativeContextSlot(Context::CALL_AS_FUNCTION_DELEGATE_INDEX, a1);
+  __ Jump(masm->isolate()->builtins()->CallFunction(
+              ConvertReceiverMode::kNotNullOrUndefined),
+          RelocInfo::CODE_TARGET);
+
+  // 3. Call to something that is not callable.
+  __ bind(&non_callable);
+  {
+    FrameScope scope(masm, StackFrame::INTERNAL);
+    __ Push(a1);
+    __ CallRuntime(Runtime::kThrowCalledNonCallable);
+  }
+}
+
+
+void Builtins::Generate_ConstructFunction(MacroAssembler* masm) {
+  // ----------- S t a t e -------------
+  //  -- a0 : the number of arguments (not including the receiver)
+  //  -- a1 : the constructor to call (checked to be a JSFunction)
+  //  -- a3 : the new target (checked to be a constructor)
+  // -----------------------------------
+  __ AssertFunction(a1);
+
+  // Calling convention for function specific ConstructStubs require
+  // a2 to contain either an AllocationSite or undefined.
+  __ LoadRoot(a2, Heap::kUndefinedValueRootIndex);
+
+  // Tail call to the function-specific construct stub (still in the caller
+  // context at this point).
+  __ ld(a4, FieldMemOperand(a1, JSFunction::kSharedFunctionInfoOffset));
+  __ ld(a4, FieldMemOperand(a4, SharedFunctionInfo::kConstructStubOffset));
+  __ Daddu(at, a4, Operand(Code::kHeaderSize - kHeapObjectTag));
+  __ Jump(at);
+}
+
+
+// static
+void Builtins::Generate_ConstructBoundFunction(MacroAssembler* masm) {
+  // ----------- S t a t e -------------
+  //  -- a0 : the number of arguments (not including the receiver)
+  //  -- a1 : the function to call (checked to be a JSBoundFunction)
+  //  -- a3 : the new target (checked to be a constructor)
+  // -----------------------------------
+  __ AssertBoundFunction(a1);
+
+  // Load [[BoundArguments]] into a2 and length of that into a4.
+  __ ld(a2, FieldMemOperand(a1, JSBoundFunction::kBoundArgumentsOffset));
+  __ ld(a4, FieldMemOperand(a2, FixedArray::kLengthOffset));
+  __ SmiUntag(a4);
+
+  // ----------- S t a t e -------------
+  //  -- a0 : the number of arguments (not including the receiver)
+  //  -- a1 : the function to call (checked to be a JSBoundFunction)
+  //  -- a2 : the [[BoundArguments]] (implemented as FixedArray)
+  //  -- a3 : the new target (checked to be a constructor)
+  //  -- a4 : the number of [[BoundArguments]]
+  // -----------------------------------
+
+  // Reserve stack space for the [[BoundArguments]].
+  {
+    Label done;
+    __ dsll(a5, a4, kPointerSizeLog2);
+    __ Dsubu(sp, sp, Operand(a5));
+    // Check the stack for overflow. We are not trying to catch interruptions
+    // (i.e. debug break and preemption) here, so check the "real stack limit".
+    __ LoadRoot(at, Heap::kRealStackLimitRootIndex);
+    __ Branch(&done, gt, sp, Operand(at));  // Signed comparison.
+    // Restore the stack pointer.
+    __ Daddu(sp, sp, Operand(a5));
+    {
+      FrameScope scope(masm, StackFrame::MANUAL);
+      __ EnterFrame(StackFrame::INTERNAL);
+      __ CallRuntime(Runtime::kThrowStackOverflow);
+    }
+    __ bind(&done);
+  }
+
+  // Relocate arguments down the stack.
+  {
+    Label loop, done_loop;
+    __ mov(a5, zero_reg);
+    __ bind(&loop);
+    __ Branch(&done_loop, ge, a5, Operand(a0));
+    __ dsll(a6, a4, kPointerSizeLog2);
+    __ daddu(a6, a6, sp);
+    __ ld(at, MemOperand(a6));
+    __ dsll(a6, a5, kPointerSizeLog2);
+    __ daddu(a6, a6, sp);
+    __ sd(at, MemOperand(a6));
+    __ Daddu(a4, a4, Operand(1));
+    __ Daddu(a5, a5, Operand(1));
+    __ Branch(&loop);
+    __ bind(&done_loop);
+  }
+
+  // Copy [[BoundArguments]] to the stack (below the arguments).
+  {
+    Label loop, done_loop;
+    __ ld(a4, FieldMemOperand(a2, FixedArray::kLengthOffset));
+    __ SmiUntag(a4);
+    __ Daddu(a2, a2, Operand(FixedArray::kHeaderSize - kHeapObjectTag));
+    __ bind(&loop);
+    __ Dsubu(a4, a4, Operand(1));
+    __ Branch(&done_loop, lt, a4, Operand(zero_reg));
+    __ dsll(a5, a4, kPointerSizeLog2);
+    __ daddu(a5, a5, a2);
+    __ ld(at, MemOperand(a5));
+    __ dsll(a5, a0, kPointerSizeLog2);
+    __ daddu(a5, a5, sp);
+    __ sd(at, MemOperand(a5));
+    __ Daddu(a0, a0, Operand(1));
+    __ Branch(&loop);
+    __ bind(&done_loop);
+  }
+
+  // Patch new.target to [[BoundTargetFunction]] if new.target equals target.
+  {
+    Label skip_load;
+    __ Branch(&skip_load, ne, a1, Operand(a3));
+    __ ld(a3, FieldMemOperand(a1, JSBoundFunction::kBoundTargetFunctionOffset));
+    __ bind(&skip_load);
+  }
+
+  // Construct the [[BoundTargetFunction]] via the Construct builtin.
+  __ ld(a1, FieldMemOperand(a1, JSBoundFunction::kBoundTargetFunctionOffset));
+  __ li(at, Operand(ExternalReference(Builtins::kConstruct, masm->isolate())));
+  __ ld(at, MemOperand(at));
+  __ Daddu(at, at, Operand(Code::kHeaderSize - kHeapObjectTag));
+  __ Jump(at);
+}
+
+
+// static
+void Builtins::Generate_ConstructProxy(MacroAssembler* masm) {
+  // ----------- S t a t e -------------
+  //  -- a0 : the number of arguments (not including the receiver)
+  //  -- a1 : the constructor to call (checked to be a JSProxy)
+  //  -- a3 : the new target (either the same as the constructor or
+  //          the JSFunction on which new was invoked initially)
+  // -----------------------------------
+
+  // Call into the Runtime for Proxy [[Construct]].
+  __ Push(a1, a3);
+  // Include the pushed new_target, constructor and the receiver.
+  __ Daddu(a0, a0, Operand(3));
+  // Tail-call to the runtime.
+  __ JumpToExternalReference(
+      ExternalReference(Runtime::kJSProxyConstruct, masm->isolate()));
+}
+
+
+// static
+void Builtins::Generate_Construct(MacroAssembler* masm) {
+  // ----------- S t a t e -------------
+  //  -- a0 : the number of arguments (not including the receiver)
+  //  -- a1 : the constructor to call (can be any Object)
+  //  -- a3 : the new target (either the same as the constructor or
+  //          the JSFunction on which new was invoked initially)
+  // -----------------------------------
+
+  // Check if target is a Smi.
+  Label non_constructor;
+  __ JumpIfSmi(a1, &non_constructor);
+
+  // Dispatch based on instance type.
+  __ ld(t1, FieldMemOperand(a1, HeapObject::kMapOffset));
+  __ lbu(t2, FieldMemOperand(t1, Map::kInstanceTypeOffset));
+  __ Jump(masm->isolate()->builtins()->ConstructFunction(),
+          RelocInfo::CODE_TARGET, eq, t2, Operand(JS_FUNCTION_TYPE));
+
+  // Check if target has a [[Construct]] internal method.
+  __ lbu(t3, FieldMemOperand(t1, Map::kBitFieldOffset));
+  __ And(t3, t3, Operand(1 << Map::kIsConstructor));
+  __ Branch(&non_constructor, eq, t3, Operand(zero_reg));
+
+  // Only dispatch to bound functions after checking whether they are
+  // constructors.
+  __ Jump(masm->isolate()->builtins()->ConstructBoundFunction(),
+          RelocInfo::CODE_TARGET, eq, t2, Operand(JS_BOUND_FUNCTION_TYPE));
+
+  // Only dispatch to proxies after checking whether they are constructors.
+  __ Jump(masm->isolate()->builtins()->ConstructProxy(), RelocInfo::CODE_TARGET,
+          eq, t2, Operand(JS_PROXY_TYPE));
+
+  // Called Construct on an exotic Object with a [[Construct]] internal method.
+  {
+    // Overwrite the original receiver with the (original) target.
+    __ dsll(at, a0, kPointerSizeLog2);
+    __ daddu(at, sp, at);
+    __ sd(a1, MemOperand(at));
+    // Let the "call_as_constructor_delegate" take care of the rest.
+    __ LoadNativeContextSlot(Context::CALL_AS_CONSTRUCTOR_DELEGATE_INDEX, a1);
+    __ Jump(masm->isolate()->builtins()->CallFunction(),
+            RelocInfo::CODE_TARGET);
+  }
+
+  // Called Construct on an Object that doesn't have a [[Construct]] internal
+  // method.
+  __ bind(&non_constructor);
+  __ Jump(masm->isolate()->builtins()->ConstructedNonConstructable(),
+          RelocInfo::CODE_TARGET);
+}
+
+
 void Builtins::Generate_ArgumentsAdaptorTrampoline(MacroAssembler* masm) {
   // State setup as expected by MacroAssembler::InvokePrologue.
   // ----------- S t a t e -------------
   //  -- a0: actual arguments count
   //  -- a1: function (passed through to callee)
   //  -- a2: expected arguments count
+  //  -- a3: new target (passed through to callee)
   // -----------------------------------
 
-  Label stack_overflow;
-  ArgumentAdaptorStackCheck(masm, &stack_overflow);
-  Label invoke, dont_adapt_arguments;
+  Label invoke, dont_adapt_arguments, stack_overflow;
 
   Label enough, too_few;
-  __ ld(a3, FieldMemOperand(a1, JSFunction::kCodeEntryOffset));
   __ Branch(&dont_adapt_arguments, eq,
       a2, Operand(SharedFunctionInfo::kDontAdaptArgumentsSentinel));
   // We use Uless as the number of argument should always be greater than 0.
@@ -1472,30 +2395,32 @@
     // a0: actual number of arguments as a smi
     // a1: function
     // a2: expected number of arguments
-    // a3: code entry to call
+    // a3: new target (passed through to callee)
     __ bind(&enough);
     EnterArgumentsAdaptorFrame(masm);
+    ArgumentAdaptorStackCheck(masm, &stack_overflow);
 
-    // Calculate copy start address into a0 and copy end address into a2.
+    // Calculate copy start address into a0 and copy end address into a4.
     __ SmiScale(a0, a0, kPointerSizeLog2);
     __ Daddu(a0, fp, a0);
     // Adjust for return address and receiver.
     __ Daddu(a0, a0, Operand(2 * kPointerSize));
     // Compute copy end address.
-    __ dsll(a2, a2, kPointerSizeLog2);
-    __ dsubu(a2, a0, a2);
+    __ dsll(a4, a2, kPointerSizeLog2);
+    __ dsubu(a4, a0, a4);
 
     // Copy the arguments (including the receiver) to the new stack frame.
     // a0: copy start address
     // a1: function
-    // a2: copy end address
-    // a3: code entry to call
+    // a2: expected number of arguments
+    // a3: new target (passed through to callee)
+    // a4: copy end address
 
     Label copy;
     __ bind(&copy);
-    __ ld(a4, MemOperand(a0));
-    __ push(a4);
-    __ Branch(USE_DELAY_SLOT, &copy, ne, a0, Operand(a2));
+    __ ld(a5, MemOperand(a0));
+    __ push(a5);
+    __ Branch(USE_DELAY_SLOT, &copy, ne, a0, Operand(a4));
     __ daddiu(a0, a0, -kPointerSize);  // In delay slot.
 
     __ jmp(&invoke);
@@ -1503,13 +2428,35 @@
 
   {  // Too few parameters: Actual < expected.
     __ bind(&too_few);
-    EnterArgumentsAdaptorFrame(masm);
 
-    // Calculate copy start address into a0 and copy end address is fp.
+    // If the function is strong we need to throw an error.
+    Label no_strong_error;
+    __ ld(a4, FieldMemOperand(a1, JSFunction::kSharedFunctionInfoOffset));
+    __ lbu(a5, FieldMemOperand(a4, SharedFunctionInfo::kStrongModeByteOffset));
+    __ And(a5, a5, Operand(1 << SharedFunctionInfo::kStrongModeBitWithinByte));
+    __ Branch(&no_strong_error, eq, a5, Operand(zero_reg));
+
+    // What we really care about is the required number of arguments.
+    DCHECK_EQ(kPointerSize, kInt64Size);
+    __ lw(a5, FieldMemOperand(a4, SharedFunctionInfo::kLengthOffset));
+    __ srl(a5, a5, 1);
+    __ Branch(&no_strong_error, ge, a0, Operand(a5));
+
+    {
+      FrameScope frame(masm, StackFrame::MANUAL);
+      EnterArgumentsAdaptorFrame(masm);
+      __ CallRuntime(Runtime::kThrowStrongModeTooFewArguments);
+    }
+
+    __ bind(&no_strong_error);
+    EnterArgumentsAdaptorFrame(masm);
+    ArgumentAdaptorStackCheck(masm, &stack_overflow);
+
+    // Calculate copy start address into a0 and copy end address into a7.
     // a0: actual number of arguments as a smi
     // a1: function
     // a2: expected number of arguments
-    // a3: code entry to call
+    // a3: new target (passed through to callee)
     __ SmiScale(a0, a0, kPointerSizeLog2);
     __ Daddu(a0, fp, a0);
     // Adjust for return address and receiver.
@@ -1521,7 +2468,7 @@
     // a0: copy start address
     // a1: function
     // a2: expected number of arguments
-    // a3: code entry to call
+    // a3: new target (passed through to callee)
     // a7: copy end address
     Label copy;
     __ bind(&copy);
@@ -1534,25 +2481,29 @@
     // Fill the remaining expected arguments with undefined.
     // a1: function
     // a2: expected number of arguments
-    // a3: code entry to call
-    __ LoadRoot(a4, Heap::kUndefinedValueRootIndex);
+    // a3: new target (passed through to callee)
+    __ LoadRoot(a5, Heap::kUndefinedValueRootIndex);
     __ dsll(a6, a2, kPointerSizeLog2);
-    __ Dsubu(a2, fp, Operand(a6));
+    __ Dsubu(a4, fp, Operand(a6));
     // Adjust for frame.
-    __ Dsubu(a2, a2, Operand(StandardFrameConstants::kFixedFrameSizeFromFp +
-                            2 * kPointerSize));
+    __ Dsubu(a4, a4, Operand(StandardFrameConstants::kFixedFrameSizeFromFp +
+                             2 * kPointerSize));
 
     Label fill;
     __ bind(&fill);
     __ Dsubu(sp, sp, kPointerSize);
-    __ Branch(USE_DELAY_SLOT, &fill, ne, sp, Operand(a2));
-    __ sd(a4, MemOperand(sp));
+    __ Branch(USE_DELAY_SLOT, &fill, ne, sp, Operand(a4));
+    __ sd(a5, MemOperand(sp));
   }
 
   // Call the entry point.
   __ bind(&invoke);
-
-  __ Call(a3);
+  __ mov(a0, a2);
+  // a0 : expected number of arguments
+  // a1 : function (passed through to callee)
+  // a3: new target (passed through to callee)
+  __ ld(a4, FieldMemOperand(a1, JSFunction::kCodeEntryOffset));
+  __ Call(a4);
 
   // Store offset of return address for deoptimizer.
   masm->isolate()->heap()->SetArgumentsAdaptorDeoptPCOffset(masm->pc_offset());
@@ -1566,13 +2517,13 @@
   // Don't adapt arguments.
   // -------------------------------------------
   __ bind(&dont_adapt_arguments);
-  __ Jump(a3);
+  __ ld(a4, FieldMemOperand(a1, JSFunction::kCodeEntryOffset));
+  __ Jump(a4);
 
   __ bind(&stack_overflow);
   {
     FrameScope frame(masm, StackFrame::MANUAL);
-    EnterArgumentsAdaptorFrame(masm);
-    __ InvokeBuiltin(Builtins::STACK_OVERFLOW, CALL_FUNCTION);
+    __ CallRuntime(Runtime::kThrowStackOverflow);
     __ break_(0xCC);
   }
 }
@@ -1580,6 +2531,7 @@
 
 #undef __
 
-} }  // namespace v8::internal
+}  // namespace internal
+}  // namespace v8
 
 #endif  // V8_TARGET_ARCH_MIPS64