Desugar %DefaultConstructorCallSuper partially in parser.

This desugars the loading of the super constructor function using the
%GetPrototype runtime function in the parser. The produced code remains
the same while fewer parts need to be glued together.

R=bmeurer@chromium.org

Review URL: https://codereview.chromium.org/1321343004

Cr-Commit-Position: refs/heads/master@{#30664}

diff --git a/src/full-codegen/arm/full-codegen-arm.cc b/src/full-codegen/arm/full-codegen-arm.cc
index d7862cd..7020a11 100644 (file)
--- a/src/full-codegen/arm/full-codegen-arm.cc
+++ b/src/full-codegen/arm/full-codegen-arm.cc
@@ -4112,13 +4112,9 @@ void FullCodeGenerator::EmitDefaultConstructorCallSuper(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   DCHECK(args->length() == 2);
 
-  // new.target
+  // Evaluate new.target and super constructor.
   VisitForStackValue(args->at(0));
-
-  // .this_function
   VisitForStackValue(args->at(1));
-  __ CallRuntime(Runtime::kGetPrototype, 1);
-  __ Push(result_register());
 
   // Load original constructor into r4.
   __ ldr(r4, MemOperand(sp, 1 * kPointerSize));

diff --git a/src/full-codegen/arm64/full-codegen-arm64.cc b/src/full-codegen/arm64/full-codegen-arm64.cc
index c45052b..2e7efca 100644 (file)
--- a/src/full-codegen/arm64/full-codegen-arm64.cc
+++ b/src/full-codegen/arm64/full-codegen-arm64.cc
@@ -3842,13 +3842,9 @@ void FullCodeGenerator::EmitDefaultConstructorCallSuper(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   DCHECK(args->length() == 2);
 
-  // new.target
+  // Evaluate new.target and super constructor.
   VisitForStackValue(args->at(0));
-
-  // .this_function
   VisitForStackValue(args->at(1));
-  __ CallRuntime(Runtime::kGetPrototype, 1);
-  __ Push(result_register());
 
   // Load original constructor into x4.
   __ Peek(x4, 1 * kPointerSize);

diff --git a/src/full-codegen/ia32/full-codegen-ia32.cc b/src/full-codegen/ia32/full-codegen-ia32.cc
index 23df7a7..8af4a7a 100644 (file)
--- a/src/full-codegen/ia32/full-codegen-ia32.cc
+++ b/src/full-codegen/ia32/full-codegen-ia32.cc
@@ -4021,13 +4021,9 @@ void FullCodeGenerator::EmitDefaultConstructorCallSuper(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   DCHECK(args->length() == 2);
 
-  // new.target
+  // Evaluate new.target and super constructor.
   VisitForStackValue(args->at(0));
-
-  // .this_function
   VisitForStackValue(args->at(1));
-  __ CallRuntime(Runtime::kGetPrototype, 1);
-  __ push(result_register());
 
   // Load original constructor into ecx.
   __ mov(ecx, Operand(esp, 1 * kPointerSize));

diff --git a/src/full-codegen/mips/full-codegen-mips.cc b/src/full-codegen/mips/full-codegen-mips.cc
index 871005e..1553c1a 100644 (file)
--- a/src/full-codegen/mips/full-codegen-mips.cc
+++ b/src/full-codegen/mips/full-codegen-mips.cc
@@ -4134,13 +4134,9 @@ void FullCodeGenerator::EmitDefaultConstructorCallSuper(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   DCHECK(args->length() == 2);
 
-  // new.target
+  // Evaluate new.target and super constructor.
   VisitForStackValue(args->at(0));
-
-  // .this_function
   VisitForStackValue(args->at(1));
-  __ CallRuntime(Runtime::kGetPrototype, 1);
-  __ Push(result_register());
 
   // Load original constructor into t0.
   __ lw(t0, MemOperand(sp, 1 * kPointerSize));

diff --git a/src/full-codegen/mips64/full-codegen-mips64.cc b/src/full-codegen/mips64/full-codegen-mips64.cc
index 8e0cc0d..311f293 100644 (file)
--- a/src/full-codegen/mips64/full-codegen-mips64.cc
+++ b/src/full-codegen/mips64/full-codegen-mips64.cc
@@ -4138,13 +4138,9 @@ void FullCodeGenerator::EmitDefaultConstructorCallSuper(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   DCHECK(args->length() == 2);
 
-  // new.target
+  // Evaluate new.target and super constructor.
   VisitForStackValue(args->at(0));
-
-  // .this_function
   VisitForStackValue(args->at(1));
-  __ CallRuntime(Runtime::kGetPrototype, 1);
-  __ Push(result_register());
 
   // Load original constructor into a4.
   __ ld(a4, MemOperand(sp, 1 * kPointerSize));

diff --git a/src/full-codegen/ppc/full-codegen-ppc.cc b/src/full-codegen/ppc/full-codegen-ppc.cc
index 5e5417b..35d03cc 100644 (file)
--- a/src/full-codegen/ppc/full-codegen-ppc.cc
+++ b/src/full-codegen/ppc/full-codegen-ppc.cc
@@ -4112,14 +4112,9 @@ void FullCodeGenerator::EmitDefaultConstructorCallSuper(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   DCHECK(args->length() == 2);
 
-  // new.target
+  // Evaluate new.target and super constructor.
   VisitForStackValue(args->at(0));
-
-  // .this_function
   VisitForStackValue(args->at(1));
-  __ CallRuntime(Runtime::kGetPrototype, 1);
-  __ mr(r4, result_register());
-  __ Push(r4);
 
   // Load original constructor into r7.
   __ LoadP(r7, MemOperand(sp, 1 * kPointerSize));

diff --git a/src/full-codegen/x64/full-codegen-x64.cc b/src/full-codegen/x64/full-codegen-x64.cc
index 4437627..b4b7a8d 100644 (file)
--- a/src/full-codegen/x64/full-codegen-x64.cc
+++ b/src/full-codegen/x64/full-codegen-x64.cc
@@ -4008,13 +4008,9 @@ void FullCodeGenerator::EmitDefaultConstructorCallSuper(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   DCHECK(args->length() == 2);
 
-  // new.target
+  // Evaluate new.target and super constructor.
   VisitForStackValue(args->at(0));
-
-  // .this_function
   VisitForStackValue(args->at(1));
-  __ CallRuntime(Runtime::kGetPrototype, 1);
-  __ Push(result_register());
 
   // Load original constructor into rcx.
   __ movp(rcx, Operand(rsp, 1 * kPointerSize));

diff --git a/src/full-codegen/x87/full-codegen-x87.cc b/src/full-codegen/x87/full-codegen-x87.cc
index 2e5768a..8ebe6d9 100644 (file)
--- a/src/full-codegen/x87/full-codegen-x87.cc
+++ b/src/full-codegen/x87/full-codegen-x87.cc
@@ -3991,13 +3991,9 @@ void FullCodeGenerator::EmitDefaultConstructorCallSuper(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   DCHECK(args->length() == 2);
 
-  // new.target
+  // Evaluate new.target and super constructor.
   VisitForStackValue(args->at(0));
-
-  // .this_function
   VisitForStackValue(args->at(1));
-  __ CallRuntime(Runtime::kGetPrototype, 1);
-  __ push(result_register());
 
   // Load original constructor into ecx.
   __ mov(ecx, Operand(esp, 1 * kPointerSize));

diff --git a/src/parser.cc b/src/parser.cc
index 07f842a..a527344 100644 (file)
--- a/src/parser.cc
+++ b/src/parser.cc
@@ -359,7 +359,7 @@ FunctionLiteral* Parser::DefaultConstructor(bool call_super, Scope* scope,
     body = new (zone()) ZoneList<Statement*>(call_super ? 2 : 1, zone());
     AddAssertIsConstruct(body, pos);
     if (call_super) {
-      // %_DefaultConstructorCallSuper(new.target, .this_function)
+      // %_DefaultConstructorCallSuper(new.target, %GetPrototype(<this-fun>))
       ZoneList<Expression*>* args =
           new (zone()) ZoneList<Expression*>(2, zone());
       VariableProxy* new_target_proxy = scope_->NewUnresolved(
@@ -369,7 +369,12 @@ FunctionLiteral* Parser::DefaultConstructor(bool call_super, Scope* scope,
       VariableProxy* this_function_proxy = scope_->NewUnresolved(
           factory(), ast_value_factory()->this_function_string(),
           Variable::NORMAL, pos);
-      args->Add(this_function_proxy, zone());
+      ZoneList<Expression*>* tmp =
+          new (zone()) ZoneList<Expression*>(1, zone());
+      tmp->Add(this_function_proxy, zone());
+      Expression* get_prototype =
+          factory()->NewCallRuntime(Runtime::kGetPrototype, tmp, pos);
+      args->Add(get_prototype, zone());
       CallRuntime* call = factory()->NewCallRuntime(
           Runtime::kInlineDefaultConstructorCallSuper, args, pos);
       body->Add(factory()->NewReturnStatement(call, pos), zone());

diff --git a/src/runtime/runtime-classes.cc b/src/runtime/runtime-classes.cc
index 6678cdd..5f09814 100644 (file)
--- a/src/runtime/runtime-classes.cc
+++ b/src/runtime/runtime-classes.cc
@@ -517,16 +517,9 @@ RUNTIME_FUNCTION(Runtime_DefaultConstructorCallSuper) {
   HandleScope scope(isolate);
   DCHECK(args.length() == 2);
   CONVERT_ARG_HANDLE_CHECKED(JSFunction, original_constructor, 0);
-  CONVERT_ARG_HANDLE_CHECKED(JSFunction, actual_constructor, 1);
+  CONVERT_ARG_HANDLE_CHECKED(JSFunction, super_constructor, 1);
   JavaScriptFrameIterator it(isolate);
 
-  // Prepare the callee to the super call. The super constructor is stored as
-  // the prototype of the constructor we are currently executing.
-  Handle<Object> super_constructor;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-      isolate, super_constructor,
-      Runtime::GetPrototype(isolate, actual_constructor));
-
   // Determine the actual arguments passed to the function.
   int argument_count = 0;
   base::SmartArrayPointer<Handle<Object>> arguments =

diff --git a/src/runtime/runtime-object.cc b/src/runtime/runtime-object.cc
index 6287c98..2098c1c 100644 (file)
--- a/src/runtime/runtime-object.cc
+++ b/src/runtime/runtime-object.cc
@@ -175,8 +175,10 @@ MaybeHandle<Object> Runtime::SetObjectProperty(Isolate* isolate,
 }
 
 
-MaybeHandle<Object> Runtime::GetPrototype(Isolate* isolate,
-                                          Handle<Object> obj) {
+RUNTIME_FUNCTION(Runtime_GetPrototype) {
+  HandleScope scope(isolate);
+  DCHECK(args.length() == 1);
+  CONVERT_ARG_HANDLE_CHECKED(Object, obj, 0);
   // We don't expect access checks to be needed on JSProxy objects.
   DCHECK(!obj->IsAccessCheckNeeded() || obj->IsJSObject());
   PrototypeIterator iter(isolate, obj, PrototypeIterator::START_AT_RECEIVER);
@@ -184,25 +186,14 @@ MaybeHandle<Object> Runtime::GetPrototype(Isolate* isolate,
     if (PrototypeIterator::GetCurrent(iter)->IsAccessCheckNeeded() &&
         !isolate->MayAccess(
             Handle<JSObject>::cast(PrototypeIterator::GetCurrent(iter)))) {
-      return isolate->factory()->null_value();
+      return isolate->heap()->null_value();
     }
     iter.AdvanceIgnoringProxies();
     if (PrototypeIterator::GetCurrent(iter)->IsJSProxy()) {
-      return PrototypeIterator::GetCurrent(iter);
+      return *PrototypeIterator::GetCurrent(iter);
     }
   } while (!iter.IsAtEnd(PrototypeIterator::END_AT_NON_HIDDEN));
-  return PrototypeIterator::GetCurrent(iter);
-}
-
-
-RUNTIME_FUNCTION(Runtime_GetPrototype) {
-  HandleScope scope(isolate);
-  DCHECK(args.length() == 1);
-  CONVERT_ARG_HANDLE_CHECKED(Object, obj, 0);
-  Handle<Object> result;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result,
-                                     Runtime::GetPrototype(isolate, obj));
-  return *result;
+  return *PrototypeIterator::GetCurrent(iter);
 }
 
 

diff --git a/src/runtime/runtime.h b/src/runtime/runtime.h
index 4495562..8a53bc8 100644 (file)
--- a/src/runtime/runtime.h
+++ b/src/runtime/runtime.h
@@ -1176,10 +1176,6 @@ class Runtime : public AllStatic {
       Isolate* isolate, Handle<Object> receiver_obj, Handle<Object> key_obj,
       LanguageMode language_mode);
 
-  // TODO(mstarzinger): Remove this once %DefaultConstructorCallSuper is gone.
-  MUST_USE_RESULT static MaybeHandle<Object> GetPrototype(
-      Isolate* isolate, Handle<Object> object);
-
   enum TypedArrayId {
     // arrayIds below should be synchronized with typedarray.js natives.
     ARRAY_ID_UINT8 = 1,