src/oat/runtime/support_interpreter.cc

/*
 * Copyright (C) 2012 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 "argument_visitor.h"
#include "callee_save_frame.h"
#include "interpreter/interpreter.h"
#include "object.h"
#include "object_utils.h"

namespace art {

// Visits arguments on the stack placing them into the shadow frame.
class BuildShadowFrameVisitor : public ArgumentVisitor {
 public:
  BuildShadowFrameVisitor(MethodHelper& caller_mh, AbstractMethod** sp,
                          ShadowFrame& sf, size_t first_arg_reg) :
    ArgumentVisitor(caller_mh, sp), sf_(sf), cur_reg_(first_arg_reg) {}

  virtual void Visit() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
    Primitive::Type type = GetParamPrimitiveType();
    switch (type) {
      case Primitive::kPrimLong:  // Fall-through.
      case Primitive::kPrimDouble:
        if (IsSplitLongOrDouble()) {
          sf_.SetVRegLong(cur_reg_, ReadSplitLongParam());
        } else {
          sf_.SetVRegLong(cur_reg_, *reinterpret_cast<jlong*>(GetParamAddress()));
        }
        break;
      case Primitive::kPrimNot:
        sf_.SetVRegReference(cur_reg_, *reinterpret_cast<Object**>(GetParamAddress()));
        break;
      case Primitive::kPrimBoolean:  // Fall-through.
      case Primitive::kPrimByte:     // Fall-through.
      case Primitive::kPrimChar:     // Fall-through.
      case Primitive::kPrimShort:    // Fall-through.
      case Primitive::kPrimInt:      // Fall-through.
      case Primitive::kPrimFloat:
        sf_.SetVReg(cur_reg_, *reinterpret_cast<jint*>(GetParamAddress()));
        break;
      case Primitive::kPrimVoid:
        LOG(FATAL) << "UNREACHABLE";
        break;
    }
    ++cur_reg_;
  }

 private:
  ShadowFrame& sf_;
  size_t cur_reg_;

  DISALLOW_COPY_AND_ASSIGN(BuildShadowFrameVisitor);
};

extern "C" uint64_t artInterpreterEntry(AbstractMethod* method, Thread* self, AbstractMethod** sp)
    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
  // Ensure we don't get thread suspension until the object arguments are safely in the shadow
  // frame.
  const char* old_cause = self->StartAssertNoThreadSuspension("Building interpreter shadow frame");
  FinishCalleeSaveFrameSetup(self, sp, Runtime::kRefsAndArgs);

  MethodHelper mh(method);
  const DexFile::CodeItem* code_item = mh.GetCodeItem();
  UniquePtr<ShadowFrame> shadow_frame(ShadowFrame::Create(code_item->registers_size_,
                                                          NULL, // No last shadow coming from quick.
                                                          method, 0));
  size_t first_arg_reg = code_item->registers_size_ - code_item->ins_size_;
  BuildShadowFrameVisitor shadow_frame_builder(mh, sp, *shadow_frame.get(), first_arg_reg);
  shadow_frame_builder.VisitArguments();
  // Push a transition back into managed code onto the linked list in thread.
  ManagedStack fragment;
  self->PushManagedStackFragment(&fragment);
  self->PushShadowFrame(shadow_frame.get());
  self->EndAssertNoThreadSuspension(old_cause);
  JValue result = interpreter::EnterInterpreterFromStub(self, mh, code_item, *shadow_frame.get());
  // Pop transition.
  self->PopManagedStackFragment(fragment);
  return result.GetJ();
}

}  // namespace art