WIN8 + AMD 下OpenCL 开发环境布置

1：下载AMD APP SDK 3.0， https://developer.amd.com/amd-accelerated-parallel-processing-app-sdk/

2：安装(过程可能比较慢)，完成后重启。

3：运行->cmd, 在命令行窗口查看OpenCL环境变量是否存在，echo %AMDAPPSDKROOT%,  echo %PATH%， 

   存在说明安装成功。

4: 新建VS2013工程， 配置项目属性：

   C/C++->General->Additional Include Directories->$(AMDAPPSDKROOT)include

   Linker->General->Additional Library Directories->$(AMDAPPSDKROOT)lib\x86_64

   Linker->Input->Additional Dependencies->OpenCL.lib

5: OpenCL_HelloWorld的代码(查看OpenCL版本)： 

#include "stdafx.h"

#include 

#include 

#include "CL/cl.h"

int _tmain(int argc, _TCHAR* argv[])

{

	cl_platform_id *platforms; 

	cl_uint num_platforms; 

	cl_int i, err, platform_index = -1;

	err = clGetPlatformIDs(0, NULL, &num_platforms);

	if (err < 0)

	{

		perror("Couldn't find any platforms\n");

		return 1; 

	}

	printf("I have platforms: %d\n", num_platforms); 

	platforms = (cl_platform_id*)malloc(sizeof(cl_platform_id) * num_platforms);

	clGetPlatformIDs(num_platforms, platforms, NULL);

	for (i = 0; i < num_platforms; i++)

	{

		err = clGetPlatformInfo(platforms[i], CL_PLATFORM_EXTENSIONS, 0, NULL, NULL);

		if (err < 0)

		{

			perror("Couldn't read extension data.\n");

			return 1;

		}

		char *name = (char*)malloc(255);

		clGetPlatformInfo(platforms[i], CL_PLATFORM_NAME, 255, name, NULL);

		printf("Platform%d name: %s\n", i, name);

		char *vendor = (char*)malloc(255);

		clGetPlatformInfo(platforms[i], CL_PLATFORM_VENDOR, 255, vendor, NULL);

		printf("Platform%d vendor: %s\n", i, vendor);

		char *version = (char*)malloc(255);

		clGetPlatformInfo(platforms[i], CL_PLATFORM_VERSION, 255, version, NULL);

		printf("Platform%d version: %s\n", i, version);

	    platform_index = i;

		free(name);

		free(vendor);

		free(version);

   	}

	free(platforms);

	getchar();

	return 0;

}

6: OpenCL_HelloWorld的代码(加载并运行一个cl)

#include "stdafx.h"

#include 

#include 

#include 

#include "CL/cl.h"

using namespace std; 

#pragma warning( disable : 4996 )

cl_int convert_string(const char *pfile, std::string &str);

int _tmain(int argc, _TCHAR* argv[])

{

	cl_int          iStatus = 0;                // 函数返回状态  

	cl_uint         uiNumPlatforms = 0;         // 平台个数  

	cl_platform_id  Platform = NULL;            // 选择的平台  

	size_t          uiSize = 0;                 // 平台版本名字字节数      

	cl_int          iErr = 0;                   // 返回参数  

	char            *pName = NULL;              // 平台版本名  

	cl_uint         uiNumDevices = 0;           // 设备数量  

	cl_device_id    *pDevices = NULL;           // 设备  

	cl_context      Context = NULL;             // 设备环境  

	cl_command_queue    CommandQueue = NULL;    // 命令队列  

	const char      *pFileName = "HelloWorld_Kernel.cl";    // cl文件名

	const char      *pFileName1 = "D:\\project\\learn\\hell_cl\\x64\\Debug\\HelloWorld_Kernel.cl";

	string          strSource = "";             // 用于存储cl文件中的代码  

	const char      *pSource;                   // 代码字符串指针  

	size_t          uiArrSourceSize[] = { 0 };  // 代码字符串长度  

	cl_program      Program = NULL;             // 程序对象  

	const char      *pInput = "gdkknvnqkc";     // 输入字符串  

	size_t          uiStrlength = strlen(pInput);   // 输入字符串长度  

	char            *pOutput = NULL;                // 输出字符串  

	cl_mem          memInutBuffer = NULL;           // 输入内存对象  

	cl_mem          memOutputBuffer = NULL;         // 输出内存对象  

	cl_kernel       Kernel = NULL;                  // 内核对象  

	size_t          uiGlobal_Work_Size[1] = { 0 };  // 用于设定内核分布 

	//-------------------1. 获得并选择可用平台-----------------------------  

	// 查询可用的平台个数，并返回状态  

	iStatus = clGetPlatformIDs(0, NULL, &uiNumPlatforms);

	if (CL_SUCCESS != iStatus)

	{

		cout << "Error: Getting platforms error" << endl;

		return 0;

	}

	// 获得平台地址  

	if (uiNumPlatforms > 0)  // 如果有可用平台  

	{

		// 根据平台数为平台分配内存空间  

		cl_platform_id *pPlatforms = (cl_platform_id *)malloc(uiNumPlatforms * sizeof(cl_platform_id));

		// 获得可用的平台  

		iStatus = clGetPlatformIDs(uiNumPlatforms, pPlatforms, NULL);

		Platform = pPlatforms[0];   // 获得第一个平台的地址  

		free(pPlatforms);           // 释放平台占用的内存空间  

	}

	// 获得平台版本名  

	// 获得平台版本名的字节数  

	iErr = clGetPlatformInfo(Platform, CL_PLATFORM_VERSION, 0, NULL, &uiSize);

	//根据字节数为平台版本名分配内存空间  

	pName = (char *)alloca(uiSize * sizeof(char));

	// 获得平台版本名字  

	iErr = clGetPlatformInfo(Platform, CL_PLATFORM_VERSION, uiSize, pName, NULL);

	cout << pName << endl;

	//--------------2. 查询GPU设备，并选择可用设备------------------------  

	// 获得GPU设备数量  

	iStatus = clGetDeviceIDs(Platform, CL_DEVICE_TYPE_GPU, 0, NULL, &uiNumDevices);

	if (0 == uiNumDevices)  // 如果没有GPU设备  

	{

		cout << "No GPU device available." << endl;

		cout << "Choose CPU as default device." << endl;

		// 选择CPU作为设备，获得设备数  

		iStatus = clGetDeviceIDs(Platform, CL_DEVICE_TYPE_CPU, 0, NULL, &uiNumDevices);

		// 为设备分配空间  

		pDevices = (cl_device_id *)malloc(uiNumDevices * sizeof(cl_device_id));

		// 获得平台  

		iStatus = clGetDeviceIDs(Platform, CL_DEVICE_TYPE_CPU, uiNumDevices, pDevices, NULL);

	}

	else

	{

		pDevices = (cl_device_id *)malloc(uiNumDevices * sizeof(cl_device_id));

		iStatus = clGetDeviceIDs(Platform, CL_DEVICE_TYPE_GPU, uiNumDevices, pDevices, NULL);

	}

	// -------------------3.创建设备环境---------------------------------  

	// 创建设备环境  

	Context = clCreateContext(NULL, 1, pDevices, NULL, NULL, NULL);

	if (NULL == Context)

	{

		cout << "Error: Can not create context" << endl;

		return 0;

	}

	// -------------------4.创建命令队列--------------------------------------  

	// 创建第1个设备的命令队列  

	CommandQueue = clCreateCommandQueue(Context, pDevices[0], 0, NULL);

	if (NULL == CommandQueue)

	{

		cout << "Error: Can not create CommandQueue" << endl;

		return 0;

	}

	// ----------------------5. 创建程序对象------------------------------  

	// 将cl文件中的代码转为字符串  

	iStatus = convert_string(pFileName1, strSource);

	pSource = strSource.c_str();            // 获得strSource指针  

	uiArrSourceSize[0] = strlen(pSource);   // 字符串大小  

	// 创建程序对象  

	Program = clCreateProgramWithSource(Context, 1, &pSource, uiArrSourceSize, NULL);

	if (NULL == Program)

	{

		cout << "Error: Can not create program" << endl;

		return 0;

	}

	// -----------------------------6. 编译程序--------------------------------  

	// 编译程序  

	iStatus = clBuildProgram(Program, 1, pDevices, NULL, NULL, NULL);

	if (CL_SUCCESS != iStatus)  // 编译错误  

	{

		cout << "Error: Can not build program" << endl;

		char szBuildLog[16384];

		clGetProgramBuildInfo(Program, *pDevices, CL_PROGRAM_BUILD_LOG, sizeof(szBuildLog), szBuildLog, NULL);

		cout << "Error in Kernel: " << endl << szBuildLog;

		clReleaseProgram(Program);

		return 0;

	}

	//-------------------------7. 并创建输入输出内核内存对象--------------------------------  

	// 创建输入内存对象  

	memInutBuffer = clCreateBuffer(

		Context,

		CL_MEM_READ_ONLY | CL_MEM_COPY_HOST_PTR,  // 输入内存为只读，并可以从宿主机内存复制到设备内存  

		(uiStrlength + 1) * sizeof(char),         // 输入内存空间大小  

		(void *)pInput,

		NULL);

	// 创建输出内存对象  

	memOutputBuffer = clCreateBuffer(

		Context,

		CL_MEM_WRITE_ONLY,                  // 输出内存只能写  

		(uiStrlength + 1) * sizeof(char),   // 输出内存空间大小  

		NULL,

		NULL);

	if ((NULL == memInutBuffer) || (NULL == memOutputBuffer))

	{

		cout << "Error creating memory objects" << endl;

		return 0;

	}

	//--------------------------8. 创建内核对象-------------------------------------  

	Kernel = clCreateKernel(Program,

		"helloworld",  // cl文件中的入口函数  

		NULL);

	if (NULL == Kernel)

	{

		cout << "Error: Can not create kernel" << endl;

		return 0;

	}

	//----------------------------9. 设置内核参数----------------------------------  

	iStatus = clSetKernelArg(Kernel,

		0,      // 参数索引  

		sizeof(cl_mem),

		(void *)&memInutBuffer);

	iStatus |= clSetKernelArg(Kernel, 1, sizeof(cl_mem), (void *)&memOutputBuffer);

	if (CL_SUCCESS != iStatus)

	{

		cout << "Error setting kernel arguments" << endl;

	}

	// --------------------------10.运行内核---------------------------------  

	uiGlobal_Work_Size[0] = uiStrlength;  // 输入字符串大小  

	// 利用命令队列使将再设备上执行的内核排队  

	iStatus = clEnqueueNDRangeKernel(

		CommandQueue,

		Kernel,

		1,

		NULL,

		uiGlobal_Work_Size,  // 确定内核在设备上的多个处理单元间的分布  

		NULL,                // 确定内核在设备上的多个处理单元间的分布  

		0,

		NULL,

		NULL);

	if (CL_SUCCESS != iStatus)

	{

		cout << "Error: Can not run kernel" << endl;

		return 0;

	}

	// ----------------------------11. 将输出读取到主机内存  

	pOutput = (char *)malloc(uiStrlength + 1);  // uiStrlength 为 输入字符串长度  

	iStatus = clEnqueueReadBuffer(

		CommandQueue,       // 命令队列  

		memOutputBuffer,    // 输出内存对象  

		CL_TRUE,            // 内核读取结束之前该函数不会返回  

		0,

		uiStrlength * sizeof(char),

		pOutput,

		0,

		NULL,

		NULL);

	if (CL_SUCCESS != iStatus)

	{

		cout << "Error: Can not reading result buffer" << endl;

		return 0;

	}

	// ---------------------12--输出计算结果---------------  

	pOutput[uiStrlength] = '\0';

	cout << "Input String:" << endl;

	cout << pInput << endl;

	cout << "Output String:" << endl;

	cout << pOutput << endl;

	// -------------------------------13. 释放资源--------------------------------  

	iStatus = clReleaseKernel(Kernel);

	iStatus = clReleaseProgram(Program);

	iStatus = clReleaseMemObject(memInutBuffer);

	iStatus = clReleaseMemObject(memOutputBuffer);

	iStatus = clReleaseCommandQueue(CommandQueue);

	iStatus = clReleaseContext(Context);

	if (NULL != pOutput)

	{

		free(pOutput);

		pOutput = NULL;

	}

	if (NULL != pDevices)

	{

		free(pDevices);

		pDevices = NULL;

	}

	getchar();

}

// 将cl文件代码转为字符串  

cl_int convert_string(const char *pFileName, std::string &Str)

{

	size_t      uiSize = 0;

	size_t      uiFileSize = 0;

	char        *pStr = NULL;

	std::fstream fFile(pFileName, (std::fstream::in | std::fstream::binary));

	if (fFile.is_open())

	{

		fFile.seekg(0, std::fstream::end);

		uiSize = uiFileSize = (size_t)fFile.tellg();  // 获得文件大小  

		fFile.seekg(0, std::fstream::beg);

		pStr = new char[uiSize + 1];

		if (NULL == pStr)

		{

			fFile.close();

			return 0;

		}

		fFile.read(pStr, uiFileSize);               // 读取uiFileSize字节  

		fFile.close();

		pStr[uiSize] = '\0';

		Str = pStr;

		delete[] pStr;

		return 0;

	}

	cout << "Error: Failed to open cl file\n:" << pFileName << endl;

	return -1;

}