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

src/mips64/builtins-mips64.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #if V8_TARGET_ARCH_MIPS64
 
 #include "src/codegen.h"
 #include "src/debug/debug.h"
 #include "src/deoptimizer.h"
 #include "src/full-codegen/full-codegen.h"
@@ skipping 1744 matching lines @@
     __ Push(a1);
     __ CallRuntime(Runtime::kThrowCalledNonCallable, 1);
   }
 }
 
 
 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 JSFunction)
+  //  -- a3 : the new target (checked to be a constructor)
   // -----------------------------------
   __ AssertFunction(a1);
-  __ AssertFunction(a3);
 
   // 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));
@@ skipping 216 matching lines @@
   }
 }
 
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_MIPS64