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/*
 * 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.
 */

#ifndef ART_COMPILER_DEX_BACKEND_H_
#define ART_COMPILER_DEX_BACKEND_H_

namespace art {

class ArenaAllocator;
class CompiledMethod;

class Backend {
  public:
    virtual ~Backend() {}
    virtual void Materialize() = 0;
    virtual CompiledMethod* GetCompiledMethod() = 0;

    // Queries for backend support for vectors
    /*
     * Return the number of bits in a vector register.
     * @return 0 if vector registers are not supported, or the
     * number of bits in the vector register if supported.
     */
    virtual int VectorRegisterSize() { return 0; }

    /*
     * Return the number of reservable vector registers supported
     * @param fp_used  ‘true’ if floating point computations will be
     * executed while vector registers are reserved.
     * @return the number of vector registers that are available
     * @note The backend should ensure that sufficient vector registers
     * are held back to generate scalar code without exhausting vector
     * registers, if scalar code also uses the vector registers.
     */
    virtual int NumReservableVectorRegisters(bool fp_used) { return 0; }

  protected:
    explicit Backend(ArenaAllocator* arena) : arena_(arena) {}
    ArenaAllocator* const arena_;
};  // Class Backend

}  // namespace art

#endif  // ART_COMPILER_DEX_BACKEND_H_