[es6] Make new.target work in functions

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.
 
 #include "src/v8.h"
 
 #if V8_TARGET_ARCH_ARM64
 
 #include "src/codegen.h"
 #include "src/debug.h"
@@ skipping 313 matching lines @@
     __ Push(original_constructor);
     __ CallRuntime(Runtime::kNewObject, 2);
     __ Mov(x4, x0);
     __ jmp(allocated);
   }
 }
 
 
 static void Generate_JSConstructStubHelper(MacroAssembler* masm,
                                            bool is_api_function,
+                                           bool use_new_target,
                                            bool create_memento) {
   // ----------- S t a t e -------------
   //  -- x0     : number of arguments
   //  -- x1     : constructor function
   //  -- x2     : allocation site or undefined
   //  -- x3    : original constructor
   //  -- lr     : return address
   //  -- sp[...]: constructor arguments
   // -----------------------------------
 
   ASM_LOCATION("Builtins::Generate_JSConstructStubHelper");
   // Should never create mementos for api functions.
   DCHECK(!is_api_function || !create_memento);
 
   Isolate* isolate = masm->isolate();
 
   // Enter a construct frame.
   {
     FrameScope scope(masm, StackFrame::CONSTRUCT);
 
     // Preserve the three incoming parameters on the stack.
     if (create_memento) {
       __ AssertUndefinedOrAllocationSite(x2, x10);
       __ Push(x2);
     }
 
     Register argc = x0;
     Register constructor = x1;
     Register original_constructor = x3;
-    // x1: constructor function
+
+    // Preserve the incoming parameters on the stack.
     __ SmiTag(argc);
-    __ Push(argc, constructor);
-    // sp[0] : Constructor function.
-    // sp[1]: number of arguments (smi-tagged)
+    if (use_new_target) {
+      __ Push(argc, constructor, original_constructor);
+    } else {
+      __ Push(argc, constructor);
+    }
+    // sp[0]: new.target (if used)
+    // sp[0/1]: Constructor function.
+    // sp[1/2]: number of arguments (smi-tagged)
 
     Label rt_call, count_incremented, allocated, normal_new;
     __ Cmp(constructor, original_constructor);
     __ B(eq, &normal_new);
     Generate_Runtime_NewObject(masm, create_memento, original_constructor,
                                &count_incremented, &allocated);
 
     __ Bind(&normal_new);
 
     // Try to allocate the object without transitioning into C code. If any of
@@ skipping 195 matching lines @@
     // Allocate the new receiver object using the runtime call.
     __ Bind(&rt_call);
     Generate_Runtime_NewObject(masm, create_memento, constructor,
                                &count_incremented, &allocated);
 
     // Receiver for constructor call allocated.
     // x4: JSObject
     __ Bind(&allocated);
 
     if (create_memento) {
-      __ Peek(x10, 2 * kXRegSize);
+      int offset = (use_new_target ? 3 : 2) * kXRegSize;
+      __ Peek(x10, offset);
       __ JumpIfRoot(x10, Heap::kUndefinedValueRootIndex, &count_incremented);
       // r2 is an AllocationSite. We are creating a memento from it, so we
       // need to increment the memento create count.
       __ Ldr(x5, FieldMemOperand(x10,
                                  AllocationSite::kPretenureCreateCountOffset));
       __ Add(x5, x5, Operand(Smi::FromInt(1)));
       __ Str(x5, FieldMemOperand(x10,
                                  AllocationSite::kPretenureCreateCountOffset));
       __ bind(&count_incremented);
     }
 
+    // Restore the parameters.
+    if (use_new_target) {
+      __ Pop(original_constructor);
+    }
     __ Pop(constructor);
 
-    __ Push(x4, x4);
-
     // Reload the number of arguments from the stack.
     // Set it up in x0 for the function call below.
-    // jssp[0]: receiver
-    // jssp[1]: receiver
-    // jssp[2]: number of arguments (smi-tagged)
-    __ Peek(argc, 2 * kXRegSize);  // Load number of arguments.
+    // jssp[0]: number of arguments (smi-tagged)
+    __ Peek(argc, 0);  // Load number of arguments.
     __ SmiUntag(argc);
 
+    if (use_new_target) {
+      __ Push(original_constructor, x4, x4);
+    } else {
+      __ Push(x4, x4);
+    }
+
     // Set up pointer to last argument.
     __ Add(x2, fp, StandardFrameConstants::kCallerSPOffset);
 
     // Copy arguments and receiver to the expression stack.
     // Copy 2 values every loop to use ldp/stp.
     // x0: number of arguments
     // x1: constructor function
     // x2: address of last argument (caller sp)
     // jssp[0]: receiver
     // jssp[1]: receiver
-    // jssp[2]: number of arguments (smi-tagged)
+    // jssp[2]: new.target (if used)
+    // jssp[2/3]: number of arguments (smi-tagged)
     // Compute the start address of the copy in x3.
     __ Add(x3, x2, Operand(argc, LSL, kPointerSizeLog2));
     Label loop, entry, done_copying_arguments;
     __ B(&entry);
     __ Bind(&loop);
     __ Ldp(x10, x11, MemOperand(x3, -2 * kPointerSize, PreIndex));
     __ Push(x11, x10);
     __ Bind(&entry);
     __ Cmp(x3, x2);
     __ B(gt, &loop);
@@ skipping 10 matching lines @@
       __ Ldr(cp, FieldMemOperand(constructor, JSFunction::kContextOffset));
       Handle<Code> code =
           masm->isolate()->builtins()->HandleApiCallConstruct();
       __ Call(code, RelocInfo::CODE_TARGET);
     } else {
       ParameterCount actual(argc);
       __ InvokeFunction(constructor, actual, CALL_FUNCTION, NullCallWrapper());
     }
 
     // Store offset of return address for deoptimizer.
-    if (!is_api_function) {
+    // TODO(arv): Remove the "!use_new_target" before supporting optimization
+    // of functions that reference new.target
+    if (!is_api_function && !use_new_target) {
       masm->isolate()->heap()->SetConstructStubDeoptPCOffset(masm->pc_offset());
     }
 
     // Restore the context from the frame.
     // x0: result
     // jssp[0]: receiver
-    // jssp[1]: number of arguments (smi-tagged)
+    // jssp[1]: new.target (if used)
+    // jssp[1/2]: number of arguments (smi-tagged)
     __ Ldr(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 the result is a smi, it is *not* an object in the ECMA sense.
     // x0: result
     // jssp[0]: receiver (newly allocated object)
     // jssp[1]: number of arguments (smi-tagged)
     __ JumpIfSmi(x0, &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.
     __ JumpIfObjectType(x0, x1, x3, FIRST_SPEC_OBJECT_TYPE, &exit, ge);
 
     // Throw away the result of the constructor invocation and use the
     // on-stack receiver as the result.
     __ Bind(&use_receiver);
     __ Peek(x0, 0);
 
     // Remove the receiver from the stack, remove caller arguments, and
     // return.
     __ Bind(&exit);
     // x0: result
     // jssp[0]: receiver (newly allocated object)
-    // jssp[1]: number of arguments (smi-tagged)
-    __ Peek(x1, kXRegSize);
+    // jssp[1]: new.target (if used)
+    // jssp[1/2]: number of arguments (smi-tagged)
+    int offset = (use_new_target ? 2 : 1) * kXRegSize;
+    __ Peek(x1, offset);
 
     // Leave construct frame.
   }
 
   __ DropBySMI(x1);
   __ Drop(1);
   __ IncrementCounter(isolate->counters()->constructed_objects(), 1, x1, x2);
   __ Ret();
 }
 
 
 void Builtins::Generate_JSConstructStubGeneric(MacroAssembler* masm) {
-  Generate_JSConstructStubHelper(masm, false, FLAG_pretenuring_call_new);
+  Generate_JSConstructStubHelper(masm, false, false, FLAG_pretenuring_call_new);
 }
 
 
 void Builtins::Generate_JSConstructStubApi(MacroAssembler* masm) {
-  Generate_JSConstructStubHelper(masm, true, false);
+  Generate_JSConstructStubHelper(masm, true, false, false);
 }
 
 
+void Builtins::Generate_JSConstructStubNewTarget(MacroAssembler* masm) {
+  Generate_JSConstructStubHelper(masm, false, true, FLAG_pretenuring_call_new);
+}
+
+
 void Builtins::Generate_JSConstructStubForDerived(MacroAssembler* masm) {
   // ----------- S t a t e -------------
   //  -- x0     : number of arguments
   //  -- x1     : constructor function
   //  -- x2     : allocation site or undefined
   //  -- x3    : original constructor
   //  -- lr     : return address
   //  -- sp[...]: constructor arguments
   // -----------------------------------
   ASM_LOCATION("Builtins::Generate_JSConstructStubForDerived");
@@ skipping 1117 matching lines @@
   }
 }
 
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_ARM