[builtins] Add support for NewTarget to Execution::New.

src/arm64/code-stubs-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/bootstrapper.h"
 #include "src/code-stubs.h"
 #include "src/codegen.h"
 #include "src/ic/handler-compiler.h"
@@ skipping 2823 matching lines @@
 
 
 void CallConstructStub::Generate(MacroAssembler* masm) {
   ASM_LOCATION("CallConstructStub::Generate");
   // x0 : number of arguments
   // x1 : the function to call
   // x2 : feedback vector
   // x3 : slot in feedback vector (Smi, for RecordCallTarget)
   // x4 : original constructor (for IsSuperConstructorCall)
   Register function = x1;
-  Label slow, non_function_call;
 
+  Label non_function;
   // Check that the function is not a smi.
-  __ JumpIfSmi(function, &non_function_call);
+  __ JumpIfSmi(function, &non_function);
   // Check that the function is a JSFunction.
   Register object_type = x10;
   __ JumpIfNotObjectType(function, object_type, object_type, JS_FUNCTION_TYPE,
-                         &slow);
+                         &non_function);
 
   if (RecordCallTarget()) {
     GenerateRecordCallTarget(masm, x0, function, x2, x3, x4, x5, x11, x12,
                              IsSuperConstructorCall());
 
     __ Add(x5, x2, Operand::UntagSmiAndScale(x3, kPointerSizeLog2));
     Label feedback_register_initialized;
     // Put the AllocationSite from the feedback vector into x2, or undefined.
     __ Ldr(x2, FieldMemOperand(x5, FixedArray::kHeaderSize));
     __ Ldr(x5, FieldMemOperand(x2, AllocationSite::kMapOffset));
     __ JumpIfRoot(x5, Heap::kAllocationSiteMapRootIndex,
                   &feedback_register_initialized);
     __ LoadRoot(x2, Heap::kUndefinedValueRootIndex);
     __ bind(&feedback_register_initialized);
 
     __ AssertUndefinedOrAllocationSite(x2, x5);
   }
 
   if (IsSuperConstructorCall()) {
     __ Mov(x3, x4);
   } else {
     __ Mov(x3, function);
   }
 
-  // Jump to the function-specific construct stub.
-  Register jump_reg = x4;
-  Register shared_func_info = jump_reg;
-  Register cons_stub = jump_reg;
-  Register cons_stub_code = jump_reg;
-  __ Ldr(shared_func_info,
-         FieldMemOperand(function, JSFunction::kSharedFunctionInfoOffset));
-  __ Ldr(cons_stub,
-         FieldMemOperand(shared_func_info,
-                         SharedFunctionInfo::kConstructStubOffset));
-  __ Add(cons_stub_code, cons_stub, Code::kHeaderSize - kHeapObjectTag);
-  __ Br(cons_stub_code);
+  // 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);
+  __ Br(x4);
 
-  __ Bind(&slow);
-  {
-    __ Cmp(object_type, JS_FUNCTION_PROXY_TYPE);
-    __ B(ne, &non_function_call);
-    // TODO(neis): This doesn't match the ES6 spec for [[Construct]] on proxies.
-    __ Ldr(x1, FieldMemOperand(x1, JSFunctionProxy::kConstructTrapOffset));
-    __ Jump(isolate()->builtins()->Call(), RelocInfo::CODE_TARGET);
-
-    __ Bind(&non_function_call);
-    {
-      // Determine the delegate for the target (if any).
-      FrameScope scope(masm, StackFrame::INTERNAL);
-      __ SmiTag(x0);
-      __ Push(x0, x1);
-      __ CallRuntime(Runtime::kGetConstructorDelegate, 1);
-      __ Mov(x1, x0);
-      __ Pop(x0);
-      __ SmiUntag(x0);
-    }
-    // The delegate is always a regular function.
-    __ AssertFunction(x1);
-    __ Jump(masm->isolate()->builtins()->CallFunction(),
-            RelocInfo::CODE_TARGET);
-  }
+  __ Bind(&non_function);
+  __ Mov(x3, function);
+  __ Jump(isolate()->builtins()->Construct(), RelocInfo::CODE_TARGET);
 }
 
 
 static void EmitLoadTypeFeedbackVector(MacroAssembler* masm, Register vector) {
   __ Ldr(vector, MemOperand(fp, JavaScriptFrameConstants::kFunctionOffset));
   __ Ldr(vector, FieldMemOperand(vector,
                                  JSFunction::kSharedFunctionInfoOffset));
   __ Ldr(vector, FieldMemOperand(vector,
                                  SharedFunctionInfo::kFeedbackVectorOffset));
 }
@@ skipping 3067 matching lines @@
                            MemOperand(fp, 6 * kPointerSize), NULL);
 }
 
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_ARM64