Updating SYCL For CUDA examples to CUDA 12 and latest intel llvm tip (#27)

* Ignoring VIM temporary files

* Vector Addition example update

Works with latest DPC++ and SYCL2020 features
README updated to reflect CUDA backend has USM support

* Removing unnecessary CUDA Driver types

Since intel/llvm#8197, SYCL CUDA backend uses
CUDA primary context by default, so individual context setting is no
longer required.

* Using moder queue construction

SYCL 1.2.1 device selectors have been deprecated in favour of a new
simplified form using lambdas.

* Format files

Run clang-format on files, separate commit to avoid noise

* Explicitly setting CUDA context on host task

Because of the changes on SYCL context, it is necessary now to set the
active CUDA context manually inside the host task.

Note there was some clang-formatting here as well

* Addressing feedback from Gordon

Author: Ruyk

.gitignore

@@ -34,4 +34,7 @@
 # Temporaries
 *~
 *#
-*/build
+*/build
+]
+# vim
+*.swp

examples/sgemm_interop/sycl_sgemm.cpp

@@ -25,8 +25,7 @@
 #include <iostream>
 #include <vector>
 
-#include <CL/sycl.hpp>
-#include <CL/sycl/backend/cuda.hpp>
+#include <sycl/sycl.hpp>
 
 #include <cublas_v2.h>
 #include <cuda.h>
@@ -47,25 +46,6 @@ void inline checkCudaErrorMsg(cudaError status, const char *msg) {
   }
 }
 
-void inline checkCudaErrorMsg(CUresult status, const char *msg) {
-  if (status != CUDA_SUCCESS) {
-    std::cout << "ERROR CUDA: " << msg << " - " << status << std::endl;
-    exit(EXIT_FAILURE);
-  }
-}
-
-class CUDASelector : public sycl::device_selector {
-public:
-  int operator()(const sycl::device &device) const override {
-    if(device.get_platform().get_backend() == sycl::backend::ext_oneapi_cuda){
-      std::cout << " CUDA device found " << std::endl;
-      return 1;
-    } else{
-      return -1;
-    }
-  }
-};
-
 int main() {
   using namespace sycl;
 
@@ -88,7 +68,9 @@ int main() {
   // B is a matrix fill with 1
   std::fill(std::begin(h_B), std::end(h_B), 1.0f);
 
-  sycl::queue q{CUDASelector()};
+  sycl::queue q{[](auto &d) {
+    return (d.get_platform().get_backend() == sycl::backend::ext_oneapi_cuda);
+  }};
 
   cublasHandle_t handle;
   CHECK_ERROR(cublasCreate(&handle));
@@ -104,12 +86,16 @@ int main() {
       auto d_C = b_C.get_access<sycl::access::mode::write>(h);
 
       h.host_task([=](sycl::interop_handle ih) {
-        cuCtxSetCurrent(ih.get_native_context<backend::ext_oneapi_cuda>());
+        // Set the correct cuda context & stream
+	cuCtxSetCurrent(ih.get_native_context<backend::ext_oneapi_cuda>());
         auto cuStream = ih.get_native_queue<backend::ext_oneapi_cuda>();
         cublasSetStream(handle, cuStream);
-        auto cuA = reinterpret_cast<float *>(ih.get_native_mem<backend::ext_oneapi_cuda>(d_A));
-        auto cuB = reinterpret_cast<float *>(ih.get_native_mem<backend::ext_oneapi_cuda>(d_B));
-        auto cuC = reinterpret_cast<float *>(ih.get_native_mem<backend::ext_oneapi_cuda>(d_C));
+        auto cuA = reinterpret_cast<float *>(
+            ih.get_native_mem<backend::ext_oneapi_cuda>(d_A));
+        auto cuB = reinterpret_cast<float *>(
+            ih.get_native_mem<backend::ext_oneapi_cuda>(d_B));
+        auto cuC = reinterpret_cast<float *>(
+            ih.get_native_mem<backend::ext_oneapi_cuda>(d_C));
 
         CHECK_ERROR(cublasSgemm(handle, CUBLAS_OP_N, CUBLAS_OP_N, WIDTH, HEIGHT,
                                 WIDTH, &ALPHA, cuA, WIDTH, cuB, WIDTH, &BETA,

examples/sgemm_interop/sycl_sgemm_usm.cpp

@@ -25,8 +25,7 @@
 #include <iostream>
 #include <vector>
 
-#include <CL/sycl.hpp>
-#include <CL/sycl/backend/cuda.hpp>
+#include <sycl/sycl.hpp>
 
 #include <cublas_v2.h>
 #include <cuda.h>
@@ -47,25 +46,6 @@ void inline checkCudaErrorMsg(cudaError status, const char *msg) {
   }
 }
 
-void inline checkCudaErrorMsg(CUresult status, const char *msg) {
-  if (status != CUDA_SUCCESS) {
-    std::cout << "ERROR CUDA: " << msg << " - " << status << std::endl;
-    exit(EXIT_FAILURE);
-  }
-}
-
-class CUDASelector : public sycl::device_selector {
-public:
-  int operator()(const sycl::device &device) const override {
-    if(device.get_platform().get_backend() == sycl::backend::ext_oneapi_cuda){
-      std::cout << " CUDA device found " << std::endl;
-      return 1;
-    } else{
-      return -1;
-    }
-  }
-};
-
 int main() {
   using namespace sycl;
 
@@ -88,12 +68,14 @@ int main() {
   // B is a matrix fill with 1
   std::fill(std::begin(h_B), std::end(h_B), 1.0f);
 
-  sycl::queue q{CUDASelector()};
+  sycl::queue q{[](auto &d) {
+    return (d.get_platform().get_backend() == sycl::backend::ext_oneapi_cuda);
+  }};
 
   // Allocate memory on the device
-  float* d_A = sycl::malloc_device<float>(WIDTH*HEIGHT,q);
-  float* d_B = sycl::malloc_device<float>(WIDTH*HEIGHT,q);
-  float* d_C = sycl::malloc_device<float>(WIDTH*HEIGHT,q);
+  float *d_A = sycl::malloc_device<float>(WIDTH * HEIGHT, q);
+  float *d_B = sycl::malloc_device<float>(WIDTH * HEIGHT, q);
+  float *d_C = sycl::malloc_device<float>(WIDTH * HEIGHT, q);
 
   // Copy matrices A & B to device from host vectors
   const size_t numBytes = WIDTH * HEIGHT * sizeof(float);
@@ -105,21 +87,19 @@ int main() {
   CHECK_ERROR(cublasCreate(&handle));
 
   q.submit([&](handler &h) {
-
-    h.host_task([=](sycl::interop_handle ih) {
-
-      // Set the correct cuda context & stream
-      cuCtxSetCurrent(ih.get_native_context<backend::ext_oneapi_cuda>());
-      auto cuStream = ih.get_native_queue<backend::ext_oneapi_cuda>();
-      cublasSetStream(handle, cuStream);
-
-      // Call generalised matrix-matrix multiply
-      CHECK_ERROR(cublasSgemm(handle, CUBLAS_OP_N, CUBLAS_OP_N, WIDTH, HEIGHT,
-                              WIDTH, &ALPHA, d_A, WIDTH, d_B, WIDTH, &BETA,
-                              d_C, WIDTH));
-      cuStreamSynchronize(cuStream);
-    });
-  }).wait();
+     h.host_task([=](sycl::interop_handle ih) {
+       // Set the correct cuda context & stream
+       cuCtxSetCurrent(ih.get_native_context<backend::ext_oneapi_cuda>());
+       auto cuStream = ih.get_native_queue<backend::ext_oneapi_cuda>();
+       cublasSetStream(handle, cuStream);
+
+       // Call generalised matrix-matrix multiply
+       CHECK_ERROR(cublasSgemm(handle, CUBLAS_OP_N, CUBLAS_OP_N, WIDTH, HEIGHT,
+                               WIDTH, &ALPHA, d_A, WIDTH, d_B, WIDTH, &BETA,
+                               d_C, WIDTH));
+       cuStreamSynchronize(cuStream);
+     });
+   }).wait();
 
   // Copy the result back to host
   q.memcpy(h_C.data(), d_C, numBytes).wait();

examples/vector_addition/README.md

@@ -7,9 +7,6 @@ to highlight how to build an application with SYCL for CUDA using DPC++ support,
 for which an example CMakefile is provided. For detailed documentation on how to
 migrate from CUDA to SYCL, see [SYCL For CUDA Developers](https://developer.codeplay.com/products/computecpp/ce/guides/sycl-for-cuda-developers).
 
-Note currently the CUDA backend does not support the [USM](https://github.com/intel/llvm/blob/sycl/sycl/doc/extensions/USM/USM.adoc) extension, so we use
-`sycl::buffer` and `sycl::accessors` instead.
-
 Pre-requisites
 ---------------
 

examples/vector_addition/vector_addition.cpp

@@ -34,10 +34,9 @@ int main(int argc, char *argv[]) {
 
   // Initialize input data
   {
-    const auto dwrite_t = sycl::access::mode::discard_write;
+    sycl::host_accessor h_a{bufA, sycl::write_only};
+    sycl::host_accessor h_b{bufB, sycl::write_only};
 
-    auto h_a = bufA.get_access<dwrite_t>();
-    auto h_b = bufB.get_access<dwrite_t>();
     for (int i = 0; i < N; i++) {
       h_a[i] = sin(i) * sin(i);
       h_b[i] = cos(i) * cos(i);
@@ -63,15 +62,14 @@ int main(int argc, char *argv[]) {
     auto b = bufB.get_access<read_t>(h);
     auto c = bufC.get_access<write_t>(h);
 
-    h.parallel_for(VecSize,
-                   [=](sycl::id<1> i) { c[i] = a[i] + b[i]; });
+    h.parallel_for(VecSize, [=](sycl::id<1> i) { c[i] = a[i] + b[i]; });
   };
 
   myQueue.submit(cg);
 
   {
-    const auto read_t = sycl::access::mode::read;
-    auto h_c = bufC.get_access<read_t>();
+    sycl::host_accessor h_c{bufC, sycl::read_only};
+
     double sum = 0.0f;
     for (int i = 0; i < N; i++) {
       sum += h_c[i];