Opencl : VS2017 ：N卡 ： demo

参考博客：

OpenCL 环境适配流程 : vs环境搭建 + 最简单的设备信息输出，代码。
OpenCL环境搭建、获取平台设备信息 : 上面类似的博客， 补充作用。

OpenCL开发环境搭建 : 主要是AMD SDK 的安装。

opencl编程指南 : 简单的概述，没有代码和图，只是说明相关概念

**OpenCL快速入门教程: 【好】很好的文章，部分代码，但是简单介绍了各个流程的核心函数的基本使用方法 **

资源：

OpenCL 2.0 异构计算 [第三版] （Heterogeneous Computing with OpenCL 2.0） : 【重要】 gitbook ， 中文版 ，系统的。

intel-profiling-opencl-applications-with-system-analyzer-and-platform-analyzer-520639.pdf : 电子书， 英文版，
OpenCL Optimization - 1068_GTC09.pdf ppt ， 英文版

遇到的问题解决方法：

OpenCL 性能非常差 ： 内存拷贝-》映射

主要流程：

具体实现：

vs2017 + cuda11.5 + 最简单demo

OpenCL 环境适配流程 :
cuda 的 opencl 库
G:\thirdcode\CUDA_Data\Development\include
G:\thirdcode\CUDA_Data\Development\lib\x64
OpenCL.lib

# include <stdio.h>
# include <stdlib.h>
# include <malloc.h>

# ifdef APPLE
# include <OpenCL/cl.h>
# else
# include <CL/cl.h>
# endif

void displayPlatformInfo(cl_platform_id id,
    cl_platform_info param_name,
    const char* paramNameAsStr) {
    cl_int error = 0;
    size_t paramSize = 0;
    error = clGetPlatformInfo(id, param_name, 0, NULL, &paramSize);
    char* moreInfo = (char*)malloc(sizeof(char) * paramSize);
    error = clGetPlatformInfo(id, param_name, paramSize, moreInfo, NULL);
    if (error != CL_SUCCESS) {
        perror("Unable to find any OpenCL platform information");
        return;
    }
    printf("%s: %s\n", paramNameAsStr, moreInfo);
}

int main() {

    /* OpenCL 1.1 data structures */
    cl_platform_id* platforms;

    /* OpenCL 1.1 scalar data types */
    cl_uint numOfPlatforms;
    cl_int  error;

    /*
    Get the number of platforms
    Remember that for each vendor's SDK installed on the computer,
    the number of available platform also increased.
    */
    error = clGetPlatformIDs(0, NULL, &numOfPlatforms);
    if (error != CL_SUCCESS) {
        perror("Unable to find any OpenCL platforms");
        exit(1);
    }

    // Allocate memory for the number of installed platforms.
    // alloca(...) occupies some stack space but is automatically freed on return
    platforms = (cl_platform_id*)alloca(sizeof(cl_platform_id) * numOfPlatforms);
    printf("Number of OpenCL platforms found: %d\n", numOfPlatforms);

    error = clGetPlatformIDs(numOfPlatforms, platforms, NULL);
    if (error != CL_SUCCESS) {
        perror("Unable to find any OpenCL platforms");
        exit(1);
    }
    // We invoke the API 'clPlatformInfo' twice for each parameter we're trying to extract
    // and we use the return value to create temporary data structures (on the stack) to store
    // the returned information on the second invocation.
    for (cl_uint i = 0; i < numOfPlatforms; ++i) {
        displayPlatformInfo(platforms[i], CL_PLATFORM_PROFILE, "CL_PLATFORM_PROFILE");
        displayPlatformInfo(platforms[i], CL_PLATFORM_VERSION, "CL_PLATFORM_VERSION");
        displayPlatformInfo(platforms[i], CL_PLATFORM_NAME, "CL_PLATFORM_NAME");
        displayPlatformInfo(platforms[i], CL_PLATFORM_VENDOR, "CL_PLATFORM_VENDOR");
        displayPlatformInfo(platforms[i], CL_PLATFORM_EXTENSIONS, "CL_PLATFORM_EXTENSIONS");
    }
    return 0;
}

vs2017： 内存写入和内存读出，向量相加demo

**OpenCL快速入门教程: 很好的文章，部分代码，但是简单介绍了各个流程的核心函数的基本使用方法 **

OpenCL demo : 这篇博客中的对demo的基础封装还是可以的，简单的讲解demo ， 不适合系统学习，只适合入门。