.. _program_listing_file_src_tensors_backend.h:

Program Listing for File backend.h
==================================

|exhale_lsh| :ref:`Return to documentation for file <file_src_tensors_backend.h>` (``src/tensors/backend.h``)

.. |exhale_lsh| unicode:: U+021B0 .. UPWARDS ARROW WITH TIP LEFTWARDS

.. code-block:: cpp

   #pragma once
   
   #include "common/definitions.h"
   #include "tensors/rand.h"
   
   namespace marian {
   
   // GEMM type enum
   typedef enum {
     Auto = 0,            // auto tuning between available GEMMs
     Float32 = 1,         // MKL based GEMM, fp32
     FbFp16Packed = 10,   // FBGEMM based fp16 GEMM with packing
     FbInt8Packed = 11    // FBGEMM based int8 GEMM with packing
   } GemmType;
   
   class Backend {
   protected:
     DeviceId deviceId_;
     size_t seed_;
     Ptr<RandomGenerator> randomGenerator_;
     
   public:
     Backend(DeviceId deviceId, size_t seed)
         : deviceId_(deviceId), seed_(seed), randomGenerator_(createRandomGenerator(seed, deviceId)) {}
     virtual ~Backend() {};
     virtual DeviceId getDeviceId() { return deviceId_; };
     virtual Ptr<RandomGenerator> getRandomGenerator() { return randomGenerator_; }
   
     // for GPU only, calls cudaSetDevice, does nothing on CPU. Maybe change name.
     virtual void setDevice() = 0;
     virtual void synchronize() = 0;
   
     // for CPU, sets to use optimized code for inference.
     // for GPU, this is invalid. for gpu, isOptimized() function always returns false.
     virtual void setOptimized(bool optimize) = 0;
     virtual bool isOptimized() = 0;
     // for CPU, selects different GEMM types for the inference.
     // for GPU, there's no gemm type. so, it does nothing.
     virtual void setGemmType(std::string gemmType) = 0;
     virtual GemmType getGemmType() = 0;
     // for CPU, sets quantization range of weight matrices for the inference.
     // for GPU, there's no quantization. so, it does nothing.
     virtual void setQuantizeRange(float range) = 0;
     virtual float getQuantizeRange() = 0;
   };
   
   Ptr<Backend> BackendByDeviceId(DeviceId deviceId, size_t seed);
   
   }  // namespace marian