似乎您不需要的以下行给您带来了麻烦:
queue.enqueueWriteBuffer(arrayFirst, CL_FALSE, 0, sizeOfArray, NULL, NULL, &arrayEvent);
当您实际上有要写的东西时,您需要调用写入缓冲区,而这里不是这种情况。
在完整的工作示例下方,在 PHI 上进行了测试(为了清楚起见,省略了错误处理):
#include <iostream>
#include <vector>
#include <string>
#include <CL/cl.hpp>
int main()
{
const char *kernel_str{
"kernel void k1(global int *data1, global int *data2){"
" int local_id = get_local_id(0);"
" data1[local_id] = data2[local_id] + data2[local_id];"
"}" };
cl_int err = CL_SUCCESS;
std::vector<cl::Platform> platforms;
cl::Platform::get(&platforms);
cl::Platform plat;
for (auto &p : platforms)
{
std::vector<cl::Device> devices;
p.getDevices(CL_DEVICE_TYPE_ACCELERATOR, &devices);
if (!devices.empty())
{
plat = p;
break;
}
}
if (plat() == 0)
{
std::cout << "No OpenCL platform found.";
return -1;
}
cl_context_properties properties[] =
{ CL_CONTEXT_PLATFORM, (cl_context_properties)(plat)(), 0 };
cl::Context context(CL_DEVICE_TYPE_ACCELERATOR, properties);
std::vector<cl::Device> devices = context.getInfo<CL_CONTEXT_DEVICES>();
cl::Program::Sources source(1, std::make_pair(kernel_str, strlen(kernel_str)));
cl::Program program = cl::Program(context, source);
err = program.build(devices);
cl::CommandQueue queue(context, devices[0], 0, &err);
size_t sizeOfArray = 512, sizeOfArraySecond = 512;
std::vector<int> varrayFirst(sizeOfArray);
std::vector<int> varraySecond(sizeOfArraySecond);
for (size_t x = 0; x < sizeOfArraySecond; ++x)
varraySecond[x] = x;
cl::Buffer arrayFirst(context, CL_MEM_WRITE_ONLY, sizeOfArray*sizeof(varrayFirst[0]));
cl::Buffer arraySecond(context, CL_MEM_READ_ONLY, sizeOfArraySecond*sizeof(varraySecond[0]));
cl::Event arraySecondEvent;
std::vector<cl::Event> events;
err = queue.enqueueWriteBuffer(arraySecond, CL_FALSE, 0, sizeOfArraySecond*sizeof(varraySecond[0]), &varraySecond[0], NULL, &arraySecondEvent);
events.push_back(arraySecondEvent);
cl::make_kernel<cl::Buffer&, cl::Buffer&> kernel(program, "k1");
cl::Event ev = kernel(cl::EnqueueArgs(queue, events, cl::NDRange(512), cl::NDRange(128)), arrayFirst, arraySecond);
std::vector<cl::Event> evs(1, ev);
err = queue.enqueueReadBuffer(arrayFirst, CL_TRUE, 0, sizeOfArray*sizeof(varrayFirst[0]), &varrayFirst[0], &evs); // final blocking read
std::cout << "Outputting first 10 values: " << std::endl;
for (int x = 0; x < 10; ++x)
std::cout << varrayFirst[x] << ", ";
std::cout << std::endl;
return 0;
}
输出:
Outputting first 10 values:
0, 2, 4, 6, 8, 10, 12, 14, 16, 18,