Converting all sycl buffers to uninitialised device only buffers; adding memcpyHostToDevice and memcpyDeviceToHost on syclDevice; modifying all examples to obey the new rules; moving sycl queue creating to the device based on Benoit suggestion; removing the sycl specefic condition for returning m_result in TensorReduction.h according to Benoit suggestion.

4 files changed, 74 insertions, 81 deletions

diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorDeviceSycl.h b/unsupported/Eigen/CXX11/src/Tensor/TensorDeviceSycl.h
index 4231a11ff..8333301ea 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorDeviceSycl.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorDeviceSycl.h
@@ -16,95 +16,93 @@
 #define EIGEN_CXX11_TENSOR_TENSOR_DEVICE_SYCL_H
 
 namespace Eigen {
-/// \struct BufferT is used to specialise add_sycl_buffer function for
-//  two types of buffer we have. When the MapAllocator is true, we create the
-//  sycl buffer with MapAllocator.
-/// We have to const_cast the input pointer in order to work around the fact
-/// that sycl does not accept map allocator for const pointer.
-template <typename T, bool MapAllocator>
-struct BufferT {
-  using Type = cl::sycl::buffer<T, 1, cl::sycl::map_allocator<T>>;
-  static inline void add_sycl_buffer(const T *ptr, size_t num_bytes,std::map<const void *, std::shared_ptr<void>> &buffer_map) {
-    buffer_map.insert(std::pair<const void *, std::shared_ptr<void>>(ptr, std::shared_ptr<void>(std::make_shared<Type>(Type(const_cast<T *>(ptr), cl::sycl::range<1>(num_bytes))))));
-  }
-};
-
-/// specialisation of the \ref BufferT when the MapAllocator is false. In this
-/// case we only create the device-only buffer.
-template <typename T>
-struct BufferT<T, false> {
-  using Type = cl::sycl::buffer<T, 1>;
-  static inline void add_sycl_buffer(const T *ptr, size_t num_bytes, std::map<const void *, std::shared_ptr<void>> &buffer_map) {
-    buffer_map.insert(std::pair<const void *, std::shared_ptr<void>>(ptr, std::shared_ptr<void>(std::make_shared<Type>(Type(cl::sycl::range<1>(num_bytes))))));
-  }
-};
-
 struct SyclDevice {
   /// class members
   /// sycl queue
-  cl::sycl::queue &m_queue;
+  mutable cl::sycl::queue m_queue;
   /// std::map is the container used to make sure that we create only one buffer
-  /// per pointer. The lifespan of the buffer
-  /// now depends on the lifespan of SyclDevice. If a non-read-only pointer is
-  /// needed to be accessed on the host we should manually deallocate it.
+  /// per pointer. The lifespan of the buffer now depends on the lifespan of SyclDevice.
+  /// If a non-read-only pointer is needed to be accessed on the host we should manually deallocate it.
   mutable std::map<const void *, std::shared_ptr<void>> buffer_map;
-
-  SyclDevice(cl::sycl::queue &q) : m_queue(q) {}
+  /// creating device by using selector
+  template<typename dev_Selector> SyclDevice(dev_Selector s)
+  :m_queue(cl::sycl::queue(s, [=](cl::sycl::exception_list l) {
+    for (const auto& e : l) {
+      try {
+        std::rethrow_exception(e);
+      } catch (cl::sycl::exception e) {
+          std::cout << e.what() << std::endl;
+        }
+    }
+  })) {}
   // destructor
   ~SyclDevice() { deallocate_all(); }
 
-  template <typename T>
-  void deallocate(const T *p) const {
+  template <typename T> void deallocate(T *p) const {
     auto it = buffer_map.find(p);
     if (it != buffer_map.end()) {
       buffer_map.erase(it);
+      internal::aligned_free(p);
+    }
+  }
+  void deallocate_all() const {
+    std::map<const void *, std::shared_ptr<void>>::iterator it=buffer_map.begin();
+    while (it!=buffer_map.end()) {
+      auto p=it->first;
+      buffer_map.erase(it);
+      internal::aligned_free(const_cast<void*>(p));
+      it=buffer_map.begin();
     }
+    buffer_map.clear();
   }
-  void deallocate_all() const { buffer_map.clear(); }
 
   /// creation of sycl accessor for a buffer. This function first tries to find
-  /// the buffer in the buffer_map.
-  /// If found it gets the accessor from it, if not, the function then adds an
-  /// entry by creating a sycl buffer
-  /// for that particular pointer.
-  template <cl::sycl::access::mode AcMd, bool MapAllocator, typename T>
-  inline cl::sycl::accessor<T, 1, AcMd, cl::sycl::access::target::global_buffer>
+  /// the buffer in the buffer_map. If found it gets the accessor from it, if not,
+  ///the function then adds an entry by creating a sycl buffer for that particular pointer.
+  template <cl::sycl::access::mode AcMd, typename T> inline cl::sycl::accessor<T, 1, AcMd, cl::sycl::access::target::global_buffer>
   get_sycl_accessor(size_t num_bytes, cl::sycl::handler &cgh, const T * ptr) const {
-    return (get_sycl_buffer<MapAllocator,T>(num_bytes, ptr).template get_access<AcMd, cl::sycl::access::target::global_buffer>(cgh));
+    return (get_sycl_buffer<T>(num_bytes, ptr)->template get_access<AcMd, cl::sycl::access::target::global_buffer>(cgh));
   }
 
-template <bool MapAllocator, typename T>
- inline typename BufferT<T, MapAllocator>::Type
-  get_sycl_buffer(size_t num_bytes,const T * ptr) const {
-    if(MapAllocator && !ptr){
-      eigen_assert("pointer with map_Allocator cannot be null. Please initialise the input pointer"); }
-    auto it = buffer_map.find(ptr);
-    if (it == buffer_map.end()) {
-      BufferT<T, MapAllocator>::add_sycl_buffer(ptr, num_bytes, buffer_map);
-    }
-    return (*((typename BufferT<T, MapAllocator>::Type*)((buffer_map.at(ptr).get()))));
+  template<typename T> inline  std::pair<std::map<const void *, std::shared_ptr<void>>::iterator,bool> add_sycl_buffer(const T *ptr, size_t num_bytes) const {
+    using Type = cl::sycl::buffer<T, 1>;
+    std::pair<std::map<const void *, std::shared_ptr<void>>::iterator,bool> ret = buffer_map.insert(std::pair<const void *, std::shared_ptr<void>>(ptr, std::shared_ptr<void>(new Type(cl::sycl::range<1>(num_bytes)),
+      [](void *dataMem) { delete static_cast<Type*>(dataMem); })));
+    (static_cast<Type*>(buffer_map.at(ptr).get()))->set_final_data(nullptr);
+    return ret;
+  }
+
+  template <typename T> inline cl::sycl::buffer<T, 1>* get_sycl_buffer(size_t num_bytes,const T * ptr) const {
+    return static_cast<cl::sycl::buffer<T, 1>*>(add_sycl_buffer(ptr, num_bytes).first->second.get());
   }
 
   /// allocating memory on the cpu
-  EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE void *allocate(size_t num_bytes) const {
-    return internal::aligned_malloc(num_bytes);
+  EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE void *allocate(size_t) const {
+    return internal::aligned_malloc(8);
   }
 
   // some runtime conditions that can be applied here
   bool isDeviceSuitable() const { return true; }
 
-  EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE void deallocate(void *buffer) const {
-    internal::aligned_free(buffer);
-  }
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE void memcpy(void *dst, const void *src, size_t n) const {
     ::memcpy(dst, src, n);
   }
-  EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE void memcpyHostToDevice(void *dst, const void *src, size_t n) const {
-    memcpy(dst, src, n);
+
+  template<typename T> EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE void memcpyHostToDevice(T *dst, const T *src, size_t n) const {
+    auto host_acc= (static_cast<cl::sycl::buffer<T, 1>*>(add_sycl_buffer(dst, n).first->second.get()))-> template get_access<cl::sycl::access::mode::discard_write, cl::sycl::access::target::host_buffer>();
+    memcpy(host_acc.get_pointer(), src, n);
   }
-  EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE void memcpyDeviceToHost(void *dst, const void *src, size_t n) const {
-    memcpy(dst, src, n);
+ /// whith the current implementation of sycl, the data is copied twice from device to host. This will be fixed soon.
+  template<typename T> EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE void memcpyDeviceToHost(T *dst, const T *src, size_t n) const {
+    auto it = buffer_map.find(src);
+    if (it != buffer_map.end()) {
+      auto host_acc= (static_cast<cl::sycl::buffer<T, 1>*>(it->second.get()))-> template get_access<cl::sycl::access::mode::read, cl::sycl::access::target::host_buffer>();
+      memcpy(dst,host_acc.get_pointer(),  n);
+    } else{
+      eigen_assert("no device memory found. The memory might be destroyed before creation");
+    }
   }
+
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE void memset(void *buffer, int c, size_t n) const {
     ::memset(buffer, c, n);
   }
@@ -112,6 +110,7 @@ template <bool MapAllocator, typename T>
   return 1;
   }
 };
+
 }  // end namespace Eigen
 
 #endif  // EIGEN_CXX11_TENSOR_TENSOR_DEVICE_SYCL_H
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorReduction.h b/unsupported/Eigen/CXX11/src/Tensor/TensorReduction.h
index 367bccf63..f731bf17e 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorReduction.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorReduction.h
@@ -662,13 +662,7 @@ struct TensorEvaluator<const TensorReductionOp<Op, Dims, ArgType, MakePointer_>,
     }
   }
 
-  /// required by sycl in order to extract the output accessor
-#ifndef EIGEN_USE_SYCL
-  EIGEN_DEVICE_FUNC typename MakePointer_<Scalar>::Type data() const { return NULL; }
-#else
-  EIGEN_DEVICE_FUNC typename MakePointer_<Scalar>::Type data() const {
-    return m_result; }
-#endif
+  EIGEN_DEVICE_FUNC typename MakePointer_<Scalar>::Type data() const { return m_result; }
   /// required by sycl in order to extract the accessor
   const TensorEvaluator<ArgType, Device>& impl() const { return m_impl; }
   /// added for sycl in order to construct the buffer from the sycl device
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorReductionSycl.h b/unsupported/Eigen/CXX11/src/Tensor/TensorReductionSycl.h
index 1c89132db..3daecb045 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorReductionSycl.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorReductionSycl.h
@@ -27,9 +27,9 @@ namespace internal {
 
 template<typename CoeffReturnType, typename KernelName> struct syclGenericBufferReducer{
 template<typename BufferTOut, typename BufferTIn>
-static void run(BufferTOut& bufOut, BufferTIn& bufI, const Eigen::SyclDevice& dev, size_t length, size_t local){
+static void run(BufferTOut* bufOut, BufferTIn& bufI, const Eigen::SyclDevice& dev, size_t length, size_t local){
   do {
-          auto f = [length, local, &bufOut, &bufI](cl::sycl::handler& h) mutable {
+          auto f = [length, local, bufOut, &bufI](cl::sycl::handler& h) mutable {
             cl::sycl::nd_range<1> r{cl::sycl::range<1>{std::max(length, local)},
                                     cl::sycl::range<1>{std::min(length, local)}};
             /* Two accessors are used: one to the buffer that is being reduced,
@@ -37,7 +37,7 @@ static void run(BufferTOut& bufOut, BufferTIn& bufI, const Eigen::SyclDevice& de
             auto aI =
                 bufI.template get_access<cl::sycl::access::mode::read_write>(h);
             auto aOut =
-                bufOut.template get_access<cl::sycl::access::mode::discard_write>(h);
+                bufOut->template get_access<cl::sycl::access::mode::discard_write>(h);
             cl::sycl::accessor<CoeffReturnType, 1, cl::sycl::access::mode::read_write,
                                cl::sycl::access::target::local>
                 scratch(cl::sycl::range<1>(local), h);
@@ -134,7 +134,7 @@ struct FullReducer<Self, Op, const Eigen::SyclDevice, Vectorizable> {
     /// if the shared memory is less than the GRange, we set shared_mem size to the TotalSize and in this case one kernel would be created for recursion to reduce all to one.
     if (GRange < outTileSize) outTileSize=GRange;
     // getting final out buffer at the moment the created buffer is true because there is no need for assign
-    auto out_buffer =dev.template get_sycl_buffer<true, typename Eigen::internal::remove_all<CoeffReturnType>::type>(self.dimensions().TotalSize(), output);
+    auto out_buffer =dev.template get_sycl_buffer<typename Eigen::internal::remove_all<CoeffReturnType>::type>(self.dimensions().TotalSize(), output);
     /// creating the shared memory for calculating reduction.
     /// This one is used to collect all the reduced value of shared memory as we dont have global barrier on GPU. Once it is saved we can
     /// recursively apply reduction on it in order to reduce the whole.
@@ -208,7 +208,7 @@ struct InnerReducer<Self, Op, const Eigen::SyclDevice> {
     dev.m_queue.submit([&](cl::sycl::handler &cgh) {
       // create a tuple of accessors from Evaluator
       auto tuple_of_accessors =  TensorSycl::internal::createTupleOfAccessors(cgh, self.impl());
-      auto output_accessor = dev.template get_sycl_accessor<cl::sycl::access::mode::discard_write, true>(num_coeffs_to_preserve,cgh, output);
+      auto output_accessor = dev.template get_sycl_accessor<cl::sycl::access::mode::discard_write>(num_coeffs_to_preserve,cgh, output);
 
       cgh.parallel_for<Self>( cl::sycl::nd_range<1>(cl::sycl::range<1>(GRange), cl::sycl::range<1>(tileSize)), [=](cl::sycl::nd_item<1> itemID) {
         typedef typename TensorSycl::internal::ConvertToDeviceExpression<const HostExpr>::Type DevExpr;
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorSyclExtractAccessor.h b/unsupported/Eigen/CXX11/src/Tensor/TensorSyclExtractAccessor.h
index 3af5f8cfc..b1da6858e 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorSyclExtractAccessor.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorSyclExtractAccessor.h
@@ -56,10 +56,10 @@ struct AccessorConstructor{
   -> decltype(utility::tuple::append(ExtractAccessor<Arg1>::getTuple(cgh, eval1),utility::tuple::append(ExtractAccessor<Arg2>::getTuple(cgh, eval2), ExtractAccessor<Arg3>::getTuple(cgh, eval3)))) {
     return utility::tuple::append(ExtractAccessor<Arg1>::getTuple(cgh, eval1),utility::tuple::append(ExtractAccessor<Arg2>::getTuple(cgh, eval2), ExtractAccessor<Arg3>::getTuple(cgh, eval3)));
   }
-  template< cl::sycl::access::mode AcM,  bool MapAllocator, typename Arg> static inline auto getAccessor(cl::sycl::handler& cgh, Arg eval)
-  -> decltype(utility::tuple::make_tuple( eval.device().template get_sycl_accessor<AcM, MapAllocator,
+  template< cl::sycl::access::mode AcM, typename Arg> static inline auto getAccessor(cl::sycl::handler& cgh, Arg eval)
+  -> decltype(utility::tuple::make_tuple( eval.device().template get_sycl_accessor<AcM,
   typename Eigen::internal::remove_all<typename Arg::CoeffReturnType>::type>(eval.dimensions().TotalSize(), cgh,eval.data()))){
-    return utility::tuple::make_tuple(eval.device().template get_sycl_accessor<AcM, MapAllocator, typename Eigen::internal::remove_all<typename Arg::CoeffReturnType>::type>(eval.dimensions().TotalSize(), cgh,eval.data()));
+    return utility::tuple::make_tuple(eval.device().template get_sycl_accessor<AcM, typename Eigen::internal::remove_all<typename Arg::CoeffReturnType>::type>(eval.dimensions().TotalSize(), cgh,eval.data()));
   }
 };
 
@@ -141,8 +141,8 @@ struct ExtractAccessor<TensorEvaluator<TensorAssignOp<LHSExpr, RHSExpr>, Dev> >
 template <typename PlainObjectType, int Options_, typename Dev>\
 struct ExtractAccessor<TensorEvaluator<CVQual TensorMap<PlainObjectType, Options_>, Dev> > {\
   static inline auto getTuple(cl::sycl::handler& cgh,const TensorEvaluator<CVQual TensorMap<PlainObjectType, Options_>, Dev> eval)\
-  -> decltype(AccessorConstructor::template getAccessor<ACCType, true>(cgh, eval)){\
-    return AccessorConstructor::template getAccessor<ACCType, true>(cgh, eval);\
+  -> decltype(AccessorConstructor::template getAccessor<ACCType>(cgh, eval)){\
+    return AccessorConstructor::template getAccessor<ACCType>(cgh, eval);\
   }\
 };
 TENSORMAPEXPR(const, cl::sycl::access::mode::read)
@@ -153,8 +153,8 @@ TENSORMAPEXPR(, cl::sycl::access::mode::read_write)
 template <typename Expr, typename Dev>
 struct ExtractAccessor<TensorEvaluator<const TensorForcedEvalOp<Expr>, Dev> > {
   static inline auto getTuple(cl::sycl::handler& cgh, const TensorEvaluator<const TensorForcedEvalOp<Expr>, Dev> eval)
-  -> decltype(AccessorConstructor::template getAccessor<cl::sycl::access::mode::read, false>(cgh, eval)){
-    return AccessorConstructor::template getAccessor<cl::sycl::access::mode::read, false>(cgh, eval);
+  -> decltype(AccessorConstructor::template getAccessor<cl::sycl::access::mode::read>(cgh, eval)){
+    return AccessorConstructor::template getAccessor<cl::sycl::access::mode::read>(cgh, eval);
   }
 };
 
@@ -167,8 +167,8 @@ struct ExtractAccessor<TensorEvaluator<TensorForcedEvalOp<Expr>, Dev> >
 template <typename Expr, typename Dev>
 struct ExtractAccessor<TensorEvaluator<const TensorEvalToOp<Expr>, Dev> > {
   static inline auto getTuple(cl::sycl::handler& cgh,const TensorEvaluator<const TensorEvalToOp<Expr>, Dev> eval)
-  -> decltype(utility::tuple::append(AccessorConstructor::template getAccessor<cl::sycl::access::mode::write, false>(cgh, eval), AccessorConstructor::getTuple(cgh, eval.impl()))){
-    return utility::tuple::append(AccessorConstructor::template getAccessor<cl::sycl::access::mode::write, false>(cgh, eval), AccessorConstructor::getTuple(cgh, eval.impl()));
+  -> decltype(utility::tuple::append(AccessorConstructor::template getAccessor<cl::sycl::access::mode::write>(cgh, eval), AccessorConstructor::getTuple(cgh, eval.impl()))){
+    return utility::tuple::append(AccessorConstructor::template getAccessor<cl::sycl::access::mode::write>(cgh, eval), AccessorConstructor::getTuple(cgh, eval.impl()));
   }
 };
 
@@ -181,8 +181,8 @@ struct ExtractAccessor<TensorEvaluator<TensorEvalToOp<Expr>, Dev> >
 template <typename OP, typename Dim, typename Expr, typename Dev>
 struct ExtractAccessor<TensorEvaluator<const TensorReductionOp<OP, Dim, Expr>, Dev> > {
   static inline auto getTuple(cl::sycl::handler& cgh, const TensorEvaluator<const TensorReductionOp<OP, Dim, Expr>, Dev> eval)
-  -> decltype(AccessorConstructor::template getAccessor<cl::sycl::access::mode::read, false>(cgh, eval)){
-    return AccessorConstructor::template getAccessor<cl::sycl::access::mode::read, false>(cgh, eval);
+  -> decltype(AccessorConstructor::template getAccessor<cl::sycl::access::mode::read>(cgh, eval)){
+    return AccessorConstructor::template getAccessor<cl::sycl::access::mode::read>(cgh, eval);
   }
 };