ENH: example hybrid CPU/GPU project

examples/cuda/example_cuda_project/Makefile

+include ${FSLCONFDIR}/default.mk
+
+PROJNAME = example_cuda_project
+
+# All shared library dependencies required
+# for linking CUDA libraries and executables
+# must be added as CUDALIBS
+CUDALIBS = -lcudart -lcuda
+
+# This makefile is constructed such that:
+#  - "make"             will compile only CPU binaries
+#  - "make gpu=1"       will compile both CPU and GPU binaries
+#  - "make cpu=0 gpu=1" will compile only GPU binaries
+SOFILES =
+XFILES  =
+
+cpu ?= 1
+gpu ?= 0
+
+ifeq ($(cpu), 1)
+  XFILES += example_non_cuda_exe
+endif
+
+ifeq ($(gpu), 1)
+  XFILES  += example_cuda_exe
+  SOFILES += libfsl-example_cuda_lib.so
+endif
+
+all: ${XFILES} ${SOFILES}
+
+libfsl-example_cuda_lib.so: example_cuda_lib.cu
+	${NVCC} ${NVCCFLAGS} -shared -o $@ $^ ${NVCCLDFLAGS}
+
+example_cuda_exe: example_cuda_exe.cpp libfsl-example_cuda_lib.so
+	${NVCC} ${NVCCFLAGS} -o $@ $< -lfsl-example_cuda_lib ${NVCCLDFLAGS}
+
+example_non_cuda_exe: example_non_cuda_exe.cpp
+	${CXX} ${CXXFLAGS} -o $@ $<  ${LDFLAGS}

examples/cuda/example_cuda_project/example_cuda_exe.cpp

+#include <iostream>
+
+#include "example_cuda_lib.h"
+
+int main(int argc, char *argv[]) {
+
+  if (argc < 2) {
+    std::cout << "Usage: example_cuda_exe name" << std::endl;
+    return 1;
+  }
+
+  helloworld(argv[1]);
+
+  return 0;
+}

examples/cuda/example_cuda_project/example_cuda_lib.cu

+#include <string>
+#include <iostream>
+
+#include "example_cuda_lib.h"
+
+void helloworld(std::string s) {
+
+  int   driverVersion;
+  int   runtimeVersion;
+  char *memory;
+
+  std::cout << "Hello, " << s << std::endl;
+
+  if (cudaDriverGetVersion(&driverVersion) != 0) {
+    std::cout << "Error querying CUDA driver version!" << std::endl;
+  }
+
+  std::cout << "CUDA driver version: " << driverVersion << std::endl;
+
+  if (cudaRuntimeGetVersion(&runtimeVersion) != 0) {
+    std::cout << "Error querying CUDA runtime version!" << std::endl;
+    return;
+  }
+
+  std::cout << "CUDA runtime version: " << runtimeVersion << std::endl;
+
+  if (cudaMalloc(&memory, 1024) != 0) {
+    std::cout << "Error allocating memory!" << std::endl;
+  }
+
+  if (cudaFree(memory) != 0) {
+    std::cout << "Error freeing memory!" << std::endl;
+  }
+
+  std::cout << "Successfully allocated memory on GPU" << std::endl;
+}

examples/cuda/example_cuda_project/example_cuda_lib.h

+#ifndef EXAMPLE_CPP_LIB_H
+#define EXAMPLE_CPP_LIB_H
+
+#include <string>
+#include <iostream>
+
+void helloworld(std::string s);
+
+#endif

examples/cuda/example_cuda_project/example_non_cuda_exe.cpp

+#include <iostream>
+
+int main(int argc, char *argv[]) {
+
+  if (argc < 2) {
+    std::cout << "Usage: example_non_cuda_exe name" << std::endl;
+    return 1;
+  }
+
+  std::cout << "Hello, " << argv[1] << std::endl;
+
+  return 0;
+}