以下是上述Numba CUDA代码示例翻译为C++ CUDA编程语言的对应例子:
- 向量加法
#include <iostream>
#include <cuda_runtime.h>
__global__ void vector_add(float *a, float *b, float *c, int n) {
int i = blockIdx.x * blockDim.x + threadIdx.x;
if (i < n) {
c[i] = a[i] + b[i];
}
}
int main() {
const int n = 3;
float a[] = {1.0, 2.0, 3.0};
float b[] = {4.0, 5.0, 6.0};
float c[n];
float *d_a, *d_b, *d_c;
cudaMalloc(&d_a, n * sizeof(float));
cudaMalloc(&d_b, n * sizeof(float));
cudaMalloc(&d_c, n * sizeof(float));
cudaMemcpy(d_a, a, n * sizeof(float), cudaMemcpyHostToDevice);
cudaMemcpy(d_b, b, n * sizeof(float), cudaMemcpyHostToDevice);
int threadsPerBlock = 32;
int blocksPerGrid = (n + threadsPerBlock - 1) / threadsPerBlock;
vector_add<<<blocksPerGrid, threadsPerBlock>>>(d_a, d_b, d_c, n);
cudaMemcpy(c, d_c, n * sizeof(float), cudaMemcpyDeviceToHost);
for (int i = 0; i < n; ++i) {
std::cout << c[i] << " ";
}
std::cout << std::endl;
cudaFree(d_a);
cudaFree(d_b);
cudaFree(d_c);
return 0;
}
- 矩阵乘法
__global__ void matmul(float *A, float *B, float *C, int width) {
int row = blockIdx.y * blockDim.y + threadIdx.y;
int col = blockIdx.x * blockDim.x + threadIdx.x;
float value = 0.0;
if (row < width && col < width) {
for (int i = 0; i < width; ++i) {
value += A[row * width + i] * B[i * width + col];
}
C[row * width + col] = value;
}
}
// 主函数初始化和调用方式类似于向量加法
- 向量点乘
__global__ void dot_product(float *a, float *b, float *result, int n) {
__shared__ float temp[256];
int tid = threadIdx.x;
int i = blockIdx.x * blockDim.x + threadIdx.x;
float dot = 0.0;
if (i < n) {
dot = a[i] * b[i];
}
temp[tid] = dot;
__syncthreads();
// Reduction in shared memory
for (unsigned int s = blockDim.x / 2; s > 0; s >>= 1) {
if (tid < s) {
temp[tid] += temp[tid + s];
}
__syncthreads();
}
if (tid == 0) {
atomicAdd(result, temp[0]);
}
}
// 主函数初始化和调用方式类似于向量加法
- 向量乘法
__global__ void vector_multiply(float *a, float *b, float *c, int n) {
int i = blockIdx.x * blockDim.x + threadIdx.x;
if (i < n) {
c[i] = a[i] * b[i];
}
}
// 主函数初始化和调用方式类似于向量加法
- 向量除法
__global__ void vector_divide(float *a, float *b, float *c, int n) {
int i = blockIdx.x * blockDim.x + threadIdx.x;
if (i < n) {
c[i] = a[i] / b[i];
}
}
// 主函数初始化和调用方式类似于向量加法
- 向量求和
__global__ void vector_sum(float *a, float *result, int n) {
__shared__ float temp[256];
int tid = threadIdx.x;
int i = blockIdx.x * blockDim.x + threadIdx.x;
float sum = 0.0;
if (i < n) {
sum = a[i];
}
temp[tid] = sum;
__syncthreads();
// Reduction in shared memory
for (unsigned int s = blockDim.x / 2; s > 0; s >>= 1) {
if (tid < s) {
temp[tid] += temp[tid + s];
}
__syncthreads();
}
if (tid == 0) {
atomicAdd(result, temp[0]);
}
}
// 主函数初始化和调用方式类似于向量加法
- 向量求最大值
__global__ void vector_max(float *a, float *result, int n) {
__shared__ float temp[256];
int tid = threadIdx.x;
int i = blockIdx.x * blockDim.x + threadIdx.x;
float max_val = -FLT_MAX;
if (i < n) {
max_val = a[i];
}
temp[tid] = max_val;
__syncthreads();
// Reduction in shared memory
for (unsigned int s = blockDim.x / 2; s > 0; s >>= 1) {
if (tid < s) {
temp[tid] = max(temp[tid], temp[tid + s]);
}
__syncthreads();
}
if (tid == 0) {
atomicMax(result, temp[0]);
}
}
// 主函数初始化和调用方式类似于向量加法
- 向量求最小值
__global__ void vector_min(float *a, float *result, int n) {
__shared__ float temp[256];
int tid = threadIdx.x;
int i = blockIdx.x * blockDim.x + threadIdx.x;
float min_val = FLT_MAX;
if (i < n) {
min_val = a[i];
}
temp[tid] = min_val;
__syncthreads();
// Reduction in shared memory
for (unsigned int s = blockDim.x / 2; s > 0; s >>= 1) {
if (tid < s) {
temp[tid] = min(temp[tid], temp[tid + s]);
}
__syncthreads();
}
if (tid == 0) {
atomicMin(result, temp[0]);
}
}
// 主函数初始化和调用方式类似于向量加法
- 向量排序(冒泡排序)
请注意,冒泡排序在CUDA中效率极低,因为它不是并行算法。以下代码仅为演示目的,不推荐用于实际应用。
__global__ void bubble_sort(float *arr, int n) {
int i = blockIdx.x * blockDim.x + threadIdx.x;
for (int j = 0; j < n - 1; j++) {
if (i < n - j - 1) {
if (arr[i] > arr[i + 1]) {
// Swap the elements
float temp = arr[i];
arr[i] = arr[i + 1];
arr[i + 1] = temp;
}
}
__syncthreads();
}
}
// 主函数初始化和调用方式类似于向量加法
- 向量求平均值
__global__ void vector_average(float *a, float *result, int n) {
__shared__ float temp[256];
int tid = threadIdx.x;
int i = blockIdx.x * blockDim.x + threadIdx.x;
float sum = 0.0;
if (i < n) {
sum = a[i];
}
temp[tid] = sum;
__syncthreads();
// Reduction in shared memory
for (unsigned int s = blockDim.x / 2; s > 0; s >>= 1) {
if (tid < s) {
temp[tid] += temp[tid + s];
}
__syncthreads();
}
if (tid == 0) {
atomicAdd(result, temp[0]);
}
}
// 主函数初始化和调用方式类似于向量加法,但需要除以n来得到平均值
这些代码示例展示了如何将Numba CUDA代码转换为C++ CUDA代码。请注意,在C++ CUDA中,我们通常需要更详细地管理内存分配和传输,以及并行算法的设计。此外,上述代码示例中的某些操作(如排序)在CUDA上可能不是最高效的实现方式。