[Turbofan] Implement super calls with spread bytecode in assembly code.

src/interpreter/bytecode-generator.cc

 // Copyright 2015 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/interpreter/bytecode-generator.h"
 
 #include "src/ast/compile-time-value.h"
 #include "src/ast/scopes.h"
 #include "src/builtins/builtins-constructor.h"
 #include "src/code-stubs.h"
@@ skipping 2517 matching lines @@
 void BytecodeGenerator::VisitCallSuper(Call* expr) {
   RegisterAllocationScope register_scope(this);
   SuperCallReference* super = expr->expression()->AsSuperCallReference();
 
   // Prepare the constructor to the super call.
   VisitForAccumulatorValue(super->this_function_var());
   Register constructor = register_allocator()->NewRegister();
   builder()->GetSuperConstructor(constructor);
 
   ZoneList<Expression*>* args = expr->arguments();
+  RegisterList args_regs = register_allocator()->NewGrowableRegisterList();
+  VisitArguments(args, &args_regs);
+  // The new target is loaded into the accumulator from the
+  // {new.target} variable.
+  VisitForAccumulatorValue(super->new_target_var());
 
   // When a super call contains a spread, a CallSuper AST node is only created
   // if there is exactly one spread, and it is the last argument.
   if (!args->is_empty() && args->last()->IsSpread()) {
-    RegisterList args_regs = register_allocator()->NewGrowableRegisterList();
-    Register constructor_arg =
-        register_allocator()->GrowRegisterList(&args_regs);
-    builder()->MoveRegister(constructor, constructor_arg);
-    // Reserve argument reg for new.target in correct place for runtime call.
-    // TODO(petermarshall): Remove this when changing bytecode to use the new
-    // stub.
-    Register new_target = register_allocator()->GrowRegisterList(&args_regs);
-    VisitArguments(args, &args_regs);
-    VisitForRegisterValue(super->new_target_var(), new_target);
-    builder()->NewWithSpread(args_regs);
+    builder()->NewWithSpread(constructor, args_regs);

[rmcilroy, 2017/01/16 16:28:02]

nit - add a TODO to collect type on the feedback slot.

[petermarshall, 2017/01/18 10:05:32]

Done

[petermarshall, 2017/01/18 10:05:32]

Done

   } else {
-    RegisterList args_regs = register_allocator()->NewGrowableRegisterList();
-    VisitArguments(args, &args_regs);
-    // The new target is loaded into the accumulator from the
-    // {new.target} variable.
-    VisitForAccumulatorValue(super->new_target_var());
-
     // Call construct.
     builder()->SetExpressionPosition(expr);

[rmcilroy, 2017/01/16 16:28:02]

nit - move setExpressionPosition to be outside the if (it should be set for both
new and NewWithSpread calls.

[petermarshall, 2017/01/18 10:05:32]

Oops - done

     // TODO(turbofan): For now we do gather feedback on super constructor
     // calls, utilizing the existing machinery to inline the actual call
     // target and the JSCreate for the implicit receiver allocation. This
     // is not an ideal solution for super constructor calls, but it gets
     // the job done for now. In the long run we might want to revisit this
     // and come up with a better way.
     int const feedback_slot_index = feedback_index(expr->CallFeedbackICSlot());
     builder()->New(constructor, args_regs, feedback_slot_index);
   }
 }
@@ skipping 749 matching lines @@
 }
 
 Runtime::FunctionId BytecodeGenerator::StoreKeyedToSuperRuntimeId() {
   return is_strict(language_mode()) ? Runtime::kStoreKeyedToSuper_Strict
                                     : Runtime::kStoreKeyedToSuper_Sloppy;
 }
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8