Class fields, part 3 (backends)

src/full-codegen/full-codegen.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/full-codegen/full-codegen.h"
 
 #include "src/ast/ast-numbering.h"
 #include "src/ast/ast.h"
 #include "src/ast/prettyprinter.h"
 #include "src/ast/scopes.h"
@@ skipping 1510 matching lines @@
 
   VisitForStackValue(lit->constructor());
 
   PushOperand(Smi::FromInt(lit->start_position()));
   PushOperand(Smi::FromInt(lit->end_position()));
 
   CallRuntimeWithOperands(Runtime::kDefineClass);
   PrepareForBailoutForId(lit->CreateLiteralId(), BailoutState::TOS_REGISTER);
   PushOperand(result_register());
 
+  // The below proxy exists to allow static field initializers to have the
+  // correct home object and receiver. It's only necessary if the initializers
+  // are called as a part of class definition instead of immediately after it,
+  // in which case they could simply refer to the class just constructed. The
+  // latter is actually what's currently specified, and this will need to be
+  // changed if that behavior is settled upon. See also
+  // https://github.com/tc39/proposal-class-public-fields/issues/50
+  VariableProxy* static_initializer_proxy = lit->static_initializer_proxy();
+  if (static_initializer_proxy != nullptr) {
+    Variable* variable = static_initializer_proxy->var();
+    EmitVariableAssignment(variable, Token::INIT,
+                           FeedbackVectorSlot::Invalid());
+  }
+
   // Load the "prototype" from the constructor.
   __ Move(LoadDescriptor::ReceiverRegister(), result_register());
   __ LoadRoot(LoadDescriptor::NameRegister(), Heap::kprototype_stringRootIndex);
   __ Move(LoadDescriptor::SlotRegister(), SmiFromSlot(lit->PrototypeSlot()));
   CallLoadIC();
   PrepareForBailoutForId(lit->PrototypeId(), BailoutState::TOS_REGISTER);
   PushOperand(result_register());
 
   EmitClassDefineProperties(lit);
   DropOperands(1);
@@ skipping 472 matching lines @@
   return info_->has_simple_parameters();
 }
 
 FunctionLiteral* FullCodeGenerator::literal() const { return info_->literal(); }
 
 #undef __
 
 
 }  // namespace internal
 }  // namespace v8