compiler/driver/dex_compilation_unit.cc

/*
 * Copyright (C) 2013 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "dex_compilation_unit.h"

#include "art_field.h"
#include "base/utils.h"
#include "dex/class_accessor-inl.h"
#include "dex/code_item_accessors-inl.h"
#include "dex/descriptors_names.h"
#include "mirror/class-inl.h"
#include "mirror/dex_cache.h"
#include "scoped_thread_state_change-inl.h"

namespace art {

DexCompilationUnit::DexCompilationUnit(Handle<mirror::ClassLoader> class_loader,
                                       ClassLinker* class_linker,
                                       const DexFile& dex_file,
                                       const dex::CodeItem* code_item,
                                       uint16_t class_def_idx,
                                       uint32_t method_idx,
                                       uint32_t access_flags,
                                       const VerifiedMethod* verified_method,
                                       Handle<mirror::DexCache> dex_cache,
                                       Handle<mirror::Class> compiling_class)
    : class_loader_(class_loader),
      class_linker_(class_linker),
      dex_file_(&dex_file),
      code_item_(code_item),
      class_def_idx_(class_def_idx),
      dex_method_idx_(method_idx),
      access_flags_(access_flags),
      verified_method_(verified_method),
      dex_cache_(dex_cache),
      code_item_accessor_(dex_file, code_item),
      compiling_class_(compiling_class) {}

const std::string& DexCompilationUnit::GetSymbol() {
  if (symbol_.empty()) {
    symbol_ = "dex_";
    symbol_ += MangleForJni(dex_file_->PrettyMethod(dex_method_idx_));
  }
  return symbol_;
}

bool DexCompilationUnit::RequiresConstructorBarrier() const {
  // Constructor barriers are applicable only for <init> methods.
  DCHECK(!IsStatic());
  DCHECK(IsConstructor());

  // We require a constructor barrier if there are final instance fields.
  if (GetCompilingClass().GetReference() != nullptr && !GetCompilingClass().IsNull()) {
    // Decoding class data can be slow, so iterate over fields of the compiling class if resolved.
    ScopedObjectAccess soa(Thread::Current());
    ObjPtr<mirror::Class> compiling_class = GetCompilingClass().Get();
    for (size_t i = 0, size = compiling_class->NumInstanceFields(); i != size; ++i) {
      ArtField* field = compiling_class->GetInstanceField(i);
      if (field->IsFinal()) {
        return true;
      }
    }
  } else {
    // Iterate over field definitions in the class data.
    ClassAccessor accessor(*GetDexFile(), GetClassDefIndex());
    for (const ClassAccessor::Field& field : accessor.GetInstanceFields()) {
      if (field.IsFinal()) {
        return true;
      }
    }
  }
  return false;
}

}  // namespace art