[es6] Make new.target work in functions

src/ia32/builtins-ia32.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.
 
 #include "src/v8.h"
 
 #if V8_TARGET_ARCH_IA32
 
 #include "src/code-factory.h"
 #include "src/codegen.h"
@@ skipping 120 matching lines @@
   if (create_memento) {
     __ jmp(count_incremented);
   } else {
     __ jmp(allocated);
   }
 }
 
 
 static void Generate_JSConstructStubHelper(MacroAssembler* masm,
                                            bool is_api_function,
+                                           bool use_new_target,
                                            bool create_memento) {
   // ----------- S t a t e -------------
   //  -- eax: number of arguments
   //  -- edi: constructor function
   //  -- ebx: allocation site or undefined
   //  -- edx: original constructor
   // -----------------------------------
 
   // Should never create mementos for api functions.
   DCHECK(!is_api_function || !create_memento);
 
   // Enter a construct frame.
   {
     FrameScope scope(masm, StackFrame::CONSTRUCT);
 
     if (create_memento) {
       __ AssertUndefinedOrAllocationSite(ebx);
       __ push(ebx);
     }
 
-    // Store a smi-tagged arguments count on the stack.
+    // Preserve the incoming parameters on the stack.
     __ SmiTag(eax);
-    __ push(eax);
-
-    // Push the function to invoke on the stack.
-    __ push(edi);
+    __ push(eax);  // Smi-tagged arguments count.
+    __ push(edi);  // Constructor function.
+    if (use_new_target) {
+      __ push(edx);  // new.target
+    }
 
     __ cmp(edx, edi);
     Label normal_new;
     Label count_incremented;
     Label allocated;
     __ j(equal, &normal_new);
 
     // Original constructor and function are different.
     Generate_Runtime_NewObject(masm, create_memento, edx, &count_incremented,
                                &allocated);
@@ skipping 207 matching lines @@
 
     // Allocate the new receiver object using the runtime call.
     __ bind(&rt_call);
     Generate_Runtime_NewObject(masm, create_memento, edi, &count_incremented,
                                &allocated);
     // New object allocated.
     // ebx: newly allocated object
     __ bind(&allocated);
 
     if (create_memento) {
-      __ mov(ecx, Operand(esp, kPointerSize * 2));
+      int offset = (use_new_target ? 3 : 2) * kPointerSize;
+      __ mov(ecx, Operand(esp, offset));
       __ cmp(ecx, masm->isolate()->factory()->undefined_value());
       __ j(equal, &count_incremented);
       // ecx is an AllocationSite. We are creating a memento from it, so we
       // need to increment the memento create count.
       __ add(FieldOperand(ecx, AllocationSite::kPretenureCreateCountOffset),
              Immediate(Smi::FromInt(1)));
       __ bind(&count_incremented);
     }
 
-    // Retrieve the function from the stack.
-    __ pop(edi);
+    // Restore the parameters.
+    if (use_new_target) {
+      __ pop(edx);  // new.target
+    }
+    __ pop(edi);  // Constructor function.
 
     // Retrieve smi-tagged arguments count from the stack.
     __ mov(eax, Operand(esp, 0));
     __ SmiUntag(eax);
 
+    // Push new.target onto the construct frame. This is stored just below the
+    // receiver on the stack.
+    if (use_new_target) {
+      __ push(edx);
+    }
+
     // 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(ebx);
     __ push(ebx);
 
     // Set up pointer to last argument.
     __ lea(ebx, Operand(ebp, StandardFrameConstants::kCallerSPOffset));
 
     // Copy arguments and receiver to the expression stack.
@@ skipping 12 matching lines @@
       Handle<Code> code =
           masm->isolate()->builtins()->HandleApiCallConstruct();
       __ call(code, RelocInfo::CODE_TARGET);
     } else {
       ParameterCount actual(eax);
       __ InvokeFunction(edi, 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 context from the frame.
     __ mov(esi, Operand(ebp, 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.
     __ JumpIfSmi(eax, &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.
     __ CmpObjectType(eax, FIRST_SPEC_OBJECT_TYPE, ecx);
     __ j(above_equal, &exit);
 
     // Throw away the result of the constructor invocation and use the
     // on-stack receiver as the result.
     __ bind(&use_receiver);
     __ mov(eax, Operand(esp, 0));
 
-    // Restore the arguments count and leave the construct frame.
+    // Restore the arguments count and leave the construct frame. The arguments
+    // count is stored below the reciever and the new.target.
     __ bind(&exit);
-    __ mov(ebx, Operand(esp, kPointerSize));  // Get arguments count.
+    int offset = (use_new_target ? 2 : 1) * kPointerSize;
+    __ mov(ebx, Operand(esp, offset));
 
     // Leave construct frame.
   }
 
   // Remove caller arguments from the stack and return.
   STATIC_ASSERT(kSmiTagSize == 1 && kSmiTag == 0);
   __ pop(ecx);
   __ lea(esp, Operand(esp, ebx, times_2, 1 * kPointerSize));  // 1 ~ receiver
   __ push(ecx);
   __ IncrementCounter(masm->isolate()->counters()->constructed_objects(), 1);
   __ ret(0);
 }
 
 
 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 -------------
   //  -- eax: number of arguments
   //  -- edi: constructor function
   //  -- ebx: allocation site or undefined
   //  -- edx: original constructor
   // -----------------------------------
 
   // TODO(dslomov): support pretenuring
   CHECK(!FLAG_pretenuring_call_new);
@@ skipping 1201 matching lines @@
 
   __ bind(&ok);
   __ ret(0);
 }
 
 #undef __
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_IA32