[Proxies] Support constructable proxy as new.target (reland)

src/arm64/builtins-arm64.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #if V8_TARGET_ARCH_ARM64
 
 #include "src/arm64/frames-arm64.h"
 #include "src/codegen.h"
 #include "src/debug/debug.h"
 #include "src/deoptimizer.h"
@@ skipping 1722 matching lines @@
     __ CallRuntime(Runtime::kThrowCalledNonCallable, 1);
   }
 }
 
 
 // static
 void Builtins::Generate_ConstructFunction(MacroAssembler* masm) {
   // ----------- S t a t e -------------
   //  -- x0 : the number of arguments (not including the receiver)
   //  -- x1 : the constructor to call (checked to be a JSFunction)
-  //  -- x3 : the new target (checked to be a JSFunction)
+  //  -- x3 : the new target (checked to be a constructor)
   // -----------------------------------
   __ AssertFunction(x1);
-  __ AssertFunction(x3);
 
   // Calling convention for function specific ConstructStubs require
   // x2 to contain either an AllocationSite or undefined.
   __ LoadRoot(x2, Heap::kUndefinedValueRootIndex);
 
   // Tail call to the function-specific construct stub (still in the caller
   // context at this point).
   __ Ldr(x4, FieldMemOperand(x1, JSFunction::kSharedFunctionInfoOffset));
   __ Ldr(x4, FieldMemOperand(x4, SharedFunctionInfo::kConstructStubOffset));
   __ Add(x4, x4, Code::kHeaderSize - kHeapObjectTag);
@@ skipping 298 matching lines @@
   }
 }
 
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_ARM