Removed pre-preprocessor fenced out dead code

Renamed backend_sycl_singleton back to backend_sycl

Removed dpnp_queue_initialize_c function and
QueueOptions enum as no longer used. Removed uses of these
from examples and code base

Author: oleksandr-pavlyk

dpnp/backend/examples/example10.cpp

@@ -50,8 +50,6 @@ void test_dpnp_random_normal(const size_t size,
     double dev_time_used = 0.0;
     double sum_dev_time_used = 0.0;
 
-    dpnp_queue_initialize_c(QueueOptions::GPU_SELECTOR);
-
     double *result = (double *)dpnp_memory_alloc_c(size * sizeof(double));
 
     dpnp_rng_srand_c(seed); // TODO: will move

dpnp/backend/examples/example3.cpp

@@ -44,7 +44,6 @@ int main(int, char **)
 {
     const size_t size = 256;
 
-    dpnp_queue_initialize_c();
     std::cout << "SYCL queue is CPU: " << dpnp_queue_is_cpu_c() << std::endl;
 
     int *array1 = (int *)dpnp_memory_alloc_c(size * sizeof(int));

dpnp/backend/examples/example5.cpp

@@ -52,8 +52,6 @@ int main(int, char **)
 {
     const size_t size = 256;
 
-    dpnp_queue_initialize_c(QueueOptions::CPU_SELECTOR);
-
     double *result = (double *)dpnp_memory_alloc_c(size * sizeof(double));
 
     size_t seed = 10;

dpnp/backend/examples/example7.cpp

@@ -45,8 +45,6 @@ int main(int, char **)
     const size_t size = 2;
     size_t len = size * size;
 
-    dpnp_queue_initialize_c(QueueOptions::CPU_SELECTOR);
-
     float *array = (float *)dpnp_memory_alloc_c(len * sizeof(float));
     float *result1 = (float *)dpnp_memory_alloc_c(size * sizeof(float));
     float *result2 = (float *)dpnp_memory_alloc_c(len * sizeof(float));

dpnp/backend/examples/example8.cpp

@@ -42,8 +42,6 @@ int main(int, char **)
 {
     const size_t size = 16;
 
-    dpnp_queue_initialize_c(QueueOptions::GPU_SELECTOR);
-
     double *array = (double *)dpnp_memory_alloc_c(size * sizeof(double));
     long *result = (long *)dpnp_memory_alloc_c(size * sizeof(long));
 

dpnp/backend/examples/example9.cpp

@@ -46,8 +46,6 @@ int main(int, char **)
     long result = 0;
     long result_verification = 0;
 
-    dpnp_queue_initialize_c(QueueOptions::CPU_SELECTOR);
-
     long *array =
         reinterpret_cast<long *>(dpnp_memory_alloc_c(size * sizeof(long)));
 

dpnp/backend/examples/example_bs.cpp

@@ -229,7 +229,6 @@ int main(int, char **)
     const double RISK_FREE = 0.1;
     const double VOLATILITY = 0.2;
 
-    dpnp_queue_initialize_c(QueueOptions::GPU_SELECTOR);
     std::cout << "SYCL queue is CPU: " << dpnp_queue_is_cpu_c() << std::endl;
 
     double *price = (double *)dpnp_memory_alloc_c(SIZE * sizeof(double));

dpnp/backend/include/dpnp_iface.hpp

@@ -68,32 +68,6 @@ typedef ssize_t shape_elem_type;
  * @}
  */
 
-/**
- * @ingroup BACKEND_API
- * @brief SYCL queue initialization selector.
- *
- * The structure defines the parameters that are used for the library
- * initialization by @ref dpnp_queue_initialize_c "dpnp_queue_initialize".
- */
-enum class QueueOptions : uint32_t
-{
-    CPU_SELECTOR, /**< CPU side execution mode */
-    GPU_SELECTOR, /**< Intel GPU side execution mode */
-    AUTO_SELECTOR /**< Automatic selection based on environment variable with
-                     @ref CPU_SELECTOR default */
-};
-
-/**
- * @ingroup BACKEND_API
- * @brief SYCL queue initialization.
- *
- * Global SYCL queue initialization.
- *
- * @param [in]  selector       Select type @ref QueueOptions of the SYCL queue.
- * Default @ref AUTO_SELECTOR
- */
-INP_DLLEXPORT void dpnp_queue_initialize_c(
-    QueueOptions selector = QueueOptions::AUTO_SELECTOR);
 
 /**
  * @ingroup BACKEND_API
@@ -112,8 +86,7 @@ INP_DLLEXPORT size_t dpnp_queue_is_cpu_c();
  * @param [in]  size_in_bytes  Number of bytes for requested memory allocation.
  * @param [in]  q_ref          Reference to SYCL queue.
  *
- * @return  A pointer to newly created memory on @ref dpnp_queue_initialize_c
- * "initialized SYCL device".
+ * @return  A pointer to newly created memory on SYCL device.
  */
 INP_DLLEXPORT char *dpnp_memory_alloc_c(DPCTLSyclQueueRef q_ref,
                                         size_t size_in_bytes);

dpnp/backend/kernels/dpnp_krnl_random.cpp

@@ -70,7 +70,7 @@ static VSLStreamStatePtr get_rng_stream()
 
 void dpnp_rng_srand_c(size_t seed)
 {
-    auto &be = backend_sycl_singleton::get();
+    auto &be = backend_sycl::get();
     be.set_rng_engines_seed(seed);
     set_rng_stream(seed);
 }

dpnp/backend/src/queue_sycl.cpp

@@ -111,13 +111,8 @@ static long dpnp_kernels_link()
 }
 #endif
 
-void dpnp_queue_initialize_c(QueueOptions)
-{
-    [[maybe_unused]] auto &be = backend_sycl_singleton::get();
-}
-
 size_t dpnp_queue_is_cpu_c()
 {
-    const auto &be = backend_sycl_singleton::get();
+    const auto &be = backend_sycl::get();
     return be.backend_sycl_is_cpu();
 }