帮我用cuda语言写一个矩阵乘案例，该案例中要用到gpu的共享内存

好的，我可以为您提供一个使用 CUDA 语言编写的矩阵乘法案例，其中使用了 GPU 的共享内存。以下是代码：

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

#define TILE_WIDTH 16

__global__ void matrixMul(float *a, float *b, float *c, int width)
{
__shared__ float s_a[TILE_WIDTH][TILE_WIDTH];
__shared__ float s_b[TILE_WIDTH][TILE_WIDTH];

int bx = blockIdx.x;
int by = blockIdx.y;
int tx = threadIdx.x;
int ty = threadIdx.y;

int row = by * TILE_WIDTH + ty;
int col = bx * TILE_WIDTH + tx;

float sum = .f;

for (int i = ; i < width / TILE_WIDTH; i++) {
s_a[ty][tx] = a[row * width + i * TILE_WIDTH + tx];
s_b[ty][tx] = b[(i * TILE_WIDTH + ty) * width + col];
__syncthreads();

for (int j = ; j < TILE_WIDTH; j++) {
sum += s_a[ty][j] * s_b[j][tx];
}
__syncthreads();
}

c[row * width + col] = sum;
}

int main()
{
int width = 1024;
int size = width * width * sizeof(float);

float *h_a = (float *)malloc(size);
float *h_b = (float *)malloc(size);
float *h_c = (float *)malloc(size);

for (int i = ; i < width * width; i++) {
h_a[i] = rand() / (float)RAND_MAX;
h_b[i] = rand() / (float)RAND_MAX;
}

float *d_a, *d_b, *d_c;
cudaMalloc(&d_a, size);
cudaMalloc(&d_b, size);
cudaMalloc(&d_c, size);

cudaMemcpy(d_a, h_a, size, cudaMemcpyHostToDevice);
cudaMemcpy(d_b, h_b, size, cudaMemcpyHostToDevice);

dim3 dimBlock(TILE_WIDTH, TILE_WIDTH);
dim3 dimGrid(width / TILE_WIDTH, width / TILE_WIDTH);

matrixMul<<<dimGrid, dimBlock>>>(d_a, d_b, d_c, width);

cudaMemcpy(h_c, d_c, size, cudaMemcpyDeviceToHost);

cudaFree(d_a);
cudaFree(d_b);
cudaFree(d_c);

free(h_a);
free(h_b);
free(h_c);

return ;
}