perflab实验报告(同名8817).doc

湖南大学课程实验报告 课 程 名 称： 计算机组成与结构 实验项目名称： perflab 专 业 班 级： 姓 名： 学 号： 指 导 教 师： 完 成 时 间： 2015 年 05 月 22 日计算机科学与工程系实验题目：程序性能调优实验实验目的：kernel.c文件中主要有两个需要进行优化的函数：rotate和smooth，并分别给出了naive_rotate和naive_smooth两个函数的基本实现作为baseline作为你改进后的程序的比较对象。你需要读懂rotate和smooth函数，并对其进行优化。你每写一个新版本的、优化的rotate和smooth函数，均可在成注册后使用driver进行测试，并得到对应的CPE和加速比。本次实验，要求针对每个函数、每个人均至少写出3种优化版本、并根据driver报告的结果进行性能分析。实验环境：Vmware虚拟机 ubuntu12.04 linux终端实验步骤和结果分析：函数源码：rotate函数：void naive_rotate(int dim, pixel *src, pixel *dst) int i, j; for (i = 0; i dim; i+)for (j = 0; j dim; j+) dstRIDX(dim-1-j, i, dim) = srcRIDX(i, j, dim);rotate函数的作用是通过将每个像素进行行列调位，将一副点阵图像进行90度旋转。其中RIDX(i,j,n)即(i)*(n)+(j)。函数缺点为程序局部性不好，循环次数过多。可以对其进行分块来提高空间局部性，也可以进行循环展开。smooth函数：void naive_smooth(int dim, pixel *src, pixel *dst) int i, j; for (i = 0; i dim; i+)for (j = 0; j dim; j+) dstRIDX(i, j, dim) = avg(dim, i, j, src);smooth函数的作用是通过对图像每几点像素求平均值来对图像进行模糊化处理。函数缺点是循环次数过多和频繁调用avg函数，avg函数中又包含许多函数。应该减少avg函数的调用次数，且进行循环展开。第一种版本：CPE分析：rotate函数：void rotate(int dim, pixel *src, pixel *dst) int i,j,ii,jj; for(ii=0;iidim;ii+=4) for(jj=0;jjdim;jj+=4) for(i=ii;iii+4;i+) for(j=jj;jjj+4;j+) dstRIDX(dim-1-j,i,dim)=srcRIDX(i,j,dim);多添加了两个for函数，将循环分成了4*4的小块，在cache存储体不足够大的情况下，对循环分块能够提升高速缓存命中率，从高提升了空间局部性。从测试的CPE中也可以看出，在dim是64的时候，原代码和本代码CPE相差不大，而随着dim的增大，本代码CPE增加不大，而原代码CPE急剧增加，就是受到了cache存储的局限性。smooth函数：void smooth(int dim, pixel *src, pixel *dst)pixel_sum rowsum530530; int i, j, snum; for(i=0; idim; i+) rowsumi0.red = (srcRIDX(i, 0, dim).red+srcRIDX(i, 1, dim).red); rowsumi0.blue = (srcRIDX(i, 0, dim).blue+srcRIDX(i, 1, dim).blue); rowsumi0.green = (srcRIDX(i, 0, dim).green+srcRIDX(i, 1, dim).green); rowsumi0.num = 2; for(j=1; jdim-1; j+) rowsumij.red = (srcRIDX(i, j-1, dim).red+srcRIDX(i, j, dim).red+srcRIDX(i, j+1, dim).red); rowsumij.blue = (srcRIDX(i, j-1, dim).blue+srcRIDX(i, j, dim).blue+srcRIDX(i, j+1, dim).blue); rowsumij.green = (srcRIDX(i, j-1, dim).green+srcRIDX(i, j, dim).green+srcRIDX(i, j+1, dim).green); rowsumij.num = 3; rowsumidim-1.red = (srcRIDX(i, dim-2, dim).red+srcRIDX(i, dim-1, dim).red); rowsumidim-1.blue = (srcRIDX(i, dim-2, dim).blue+srcRIDX(i, dim-1, dim).blue); rowsumidim-1.green = (srcRIDX(i, dim-2, dim).green+srcRIDX(i, dim-1, dim).green); rowsumidim-1.num = 2; for(j=0; jdim; j+) snum = rowsum0j.num+rowsum1j.num; dstRIDX(0, j, dim).red = (unsigned short)(rowsum0j.red+rowsum1j.red)/snum); dstRIDX(0, j, dim).blue = (unsigned short)(rowsum0j.blue+rowsum1j.blue)/snum); dstRIDX(0, j, dim).green = (unsigned short)(rowsum0j.green+rowsum1j.green)/snum); for(i=1; i512时，超出了设置的数组大小会报错。第二种版本：CPE分析：rotate函数：void rotate(int dim, pixel *src, pixel *dst) int i, j; int temp; int it,jt; int im,jm; for(jt=0; jtdim; jt+=32) jm=jt+32; for(it=0; itdim; it+=32) im=it+32; for(j=jt; jjm; j+) temp=dim-1-j; for(i=it; ired=(P1-red+(P1+1)-red+P2-red+(P2+1)-red)2; dst-green=(P1-green+(P1+1)-green+P2-green+(P2+1)-green)2; dst-blue=(P1-blue+(P1+1)-blue+P2-blue+(P2+1)-blue)2; dst+; for(i=1;ired=(P1-red+(P1+1)-red+(P1+2)-red+P2-red+(P2+1)-red+(P2+2)-red)/6; dst-green=(P1-green+(P1+1)-green+(P1+2)-green+P2-green+(P2+1)-green+(P2+2)-green)/6; dst-blue=(P1-blue+(P1+1)-blue+(P1+2)-blue+P2-blue+(P2+1)-blue+(P2+2)-blue)/6; dst+; P1+; P2+; dst-red=(P1-red+(P1+1)-red+P2-red+(P2+1)-red)2; dst-green=(P1-green+(P1+1)-green+P2-green+(P2+1)-green)2; dst-blue=(P1-blue+(P1+1)-blue+P2-blue+(P2+1)-blue)2; dst+; P1=src; P2=P1+dim0; P3=P2+dim0; for(i=1;ired=(P1-red+(P1+1)-red+P2-red+(P2+1)-red+P3-red+(P3+1)-red)/6; dst-green=(P1-green+(P1+1)-green+P2-green+(P2+1)-green+P3-green+(P3+ 1)-green)/6; dst-blue=(P1-blue+(P1+1)-blue+P2-blue+(P2+1)-blue+P3-blue+(P3+1)-blue)/6; dst+; dst1=dst+1; for(j=1;jred=(P1-red+(P1+1)-red+(P1+2)-red+P2-red+(P2+1)-red+(P2+2)-red+P3-red+(P3+1)-red+(P3+2)-red)/9; dst-green=(P1-green+(P1+1)-green+(P1+2)-green+P2-green+(P2+1)-green+(P2+2)-green+P3-green+(P3+1)-green+(P3+2)-green)/9; dst-blue=(P1-blue+(P1+1)-blue+(P1+2)-blue+P2-blue+(P2+1)-blue+(P2+2)-blue+P3-blue+(P3+1)-blue+(P3+2)-blue)/9; dst1-red=(P1+3)-red+(P1+1)-red+(P1+2)-red+(P2+3)-red+(P2+1)-red+(P2+2)-red+(P3+3)-red+(P3+1)-red+(P3+2)-red)/9; dst1-green=(P1+3)-green+(P1+1)-green+(P1+2)-green+(P2+3)-green+(P2+1)-green+(P2+2)-green+(P3+3)-green+(P3+1)-green+(P3+2)-green)/9; dst1-blue=(P1+3)-blue+(P1+1)-blue+(P1+2)-blue+(P2+3)-blue+(P2+1)-blue+(P2+2)-blue+(P3+3)-blue+(P3+1)-blue+(P3+2)-blue)/9; dst+=2; dst1+=2; P1+=2; P2+=2; P3+=2; for(;jred=(P1-red+(P1+1)-red+(P1+2)-red+P2-red+(P2+1)-red+(P2+2)-red+P3-red+(P3+1)-red+(P3+2)-red)/9; dst-green=(P1-green+(P1+1)-green+(P1+2)-green+P2-green+(P2+1)-green+(P2+2)-green+P3-green+(P3+1)-green+(P3+2)-green)/9; dst-blue=(P1-blue+(P1+1)-blue+(P1+2)-blue+P2-blue+(P2+1)-blue+(P2+2)-blue+P3-blue+(P3+1)-blue+(P3+2)-blue)/9; dst+; P1+; P2+; P3+; dst-red=(P1-red+(P1+1)-red+P2-red+(P2+1)-red+P3-red+(P3+1)-red)/6; dst-green=(P1-green+(P1+1)-green+P2-green+(P2+1)-green+P3-green+(P3+1)-green)/6; dst-blue=(P1-blue+(P1+1)-blue+P2-blue+(P2+1)-blue+P3-blue+(P3+1)-blue)/6; dst+; P1+=2; P2+=2; P3+=2; dst-red=(P1-red+(P1+1)-red+P2-red+(P2+1)-red)2; dst-green=(P1-green+(P1+1)-green+P2-green+(P2+1)-green)2; dst-blue=(P1-blue+(P1+1)-blue+P2-blue+(P2+1)-blue)2; dst+; for(i=1;ired=(P1-red+(P1+1)-red+(P1+2)-red+P2-red+(P2+1)-red+(P2+2)-red)/6; dst-green=(P1-green+(P1+1)-green+(P1+2)-green+P2-green+(P2+1)-green+(P2+2)-green)/6; dst-blue=(P1-blue+(P1+1)-blue+(P1+2)-blue+P2-blue+(P2+1)-blue+(P2+2)-blue)/6; dst+; P1+; P2+; dst-red=(P1-red+(P1+1)-red+P2-red+(P2+1)-red)2; dst-green=(P1-green+(P1+1)-green+P2-green+(P2+1)-green)2; dst-blue=(P1-blue+(P1+1)-blue+P2-blue+(P2+1)-blue)2; 这段代码也是通过不调用avg函数来加速程序。将Smooth函数处理分为4块，一为主体内部，由9点求平均值；二为4个顶点，由4点求平均值；三为四条边界，由6点求平均值。从图片的顶部开始处理，再上边界，顺序处理下来，其中在处理左边界时，for循环处理一行主体部分，就是以上的代码。第三种版本：CPE分析：rotate函数：void rotate(int dim, pixel *src, pixel *dst) int i, j; int dst_base=(dim-1)*dim; dst+=dst_base; for(i=0;idim;i+=32) for(j=0;jdim;j+) *dst=*src; src+=dim; dst+; *dst=*src; src+=dim; dst+; *dst=*src; src+=dim; dst+; *dst=*src; src+=dim; dst+; *dst=*src; src+=dim; dst+; *dst=*src; src+=dim; dst+; *dst=*src; src+=dim; dst+; *dst=*src; src+=dim; dst+; *dst=*src; src+=dim; dst+; *dst=*src; src+=dim; dst+; *dst=*src; src+=dim; dst+; *dst=*src; src+=dim; dst+; *dst=*src; src+=dim; dst+; *dst=*src; src+=dim; dst+; *dst=*src; src+=dim; dst+; *dst=*src; src+=dim; dst+; *dst=*src; src+=dim; dst+; *dst=*src; src+=dim; dst+; *dst=*src; src+=dim; dst+; *dst=*src; src+=dim; dst+; *dst=*src; src+=dim; dst+; *dst=*src; src+=dim; dst+; *dst=*src; src+=dim; dst+; *dst=*src; src+=dim; dst+; *dst=*src; src+=dim; dst+; *dst=*src; src+=dim; dst+; *dst=*src; src+=dim; dst+; *dst=*src; src+=dim; dst+; *dst=*src; src+=dim; dst+; *dst=*src; src+=dim; dst+; *dst=*src; src+=dim; dst+; *dst=*src; src+; src-=(dim5)-dim; dst-=31+dim; dst+=dst_base+dim; dst+=32; src+=(dim2; dst0.blue = (src0.blue+src1.blue+srcdim.blue+srcdim+1.blue)2; dst0.green = (src0.green+src1.green+srcdim.green+srcdim+1.green)2; dstdim-1.red = (srcdim-1.red+srcdim-2.red+srcdim*2-1.red+srcdim*2-2.red)2; dstdim-1.blue = (srcdim-1.blue+srcdim-2.blue+srcdim*2-1.blue+srcdim*2-2.blue)2; dstdim-1.green = (srcdim-1.green+srcdim-2.green+srcdim*2-1.green+srcdim*2-2.green)2; dstdim*(dim-1).red = (srcdim*(dim-1).red+srcdim*(dim-1)+1.red+srcdim*(dim-2).red+srcdim*(dim-2)+1.red)2; dstdim*(dim-1).blue = (srcdim*(dim-1).blue+srcdim*(dim-1)+1.blue+srcdim*(dim-2).blue+srcdim*(dim-2)+1.blue)2; dstdim*(dim-1).green = (srcdim*(dim-1).green+srcdim*(dim-1)+1.green+srcdim*(dim-2).green+srcdim*(dim-2)+1.green)2; dstdim*dim-1.red = (srcdim*dim-1.red+srcdim*dim-2.red+srcdim*(dim-1)-1.red+srcdim*(dim-1)-2.red)2; dstdim*dim-1.blue = (srcdim*dim-1.blue+srcdim*dim-2.blue+srcdim*(dim-1)-1.blue+srcdim*(dim-1)-2.blue)2; dstdim*dim-1.green = (srcdim*dim-1.green+srcdim*dim-2.green+srcdim*(dim-1)-1.green+srcdim*(dim-1)-2.green)2; for (j = 1; j dim-1; j+) dstj.red = (srcj.red+srcj-1.red+srcj+1.red+srcj+dim.red+srcj+1+dim.red+srcj-1+dim.red)/6; dstj.green = (srcj.green+srcj-1.green+srcj+1.green+srcj+dim.green+srcj+1+dim.green+srcj-1+dim.green)/6; dstj.blue = (srcj.blue+srcj-1.blue+srcj+1.blue+srcj+dim.blue+srcj+1+dim.blue+srcj-1+dim.blue)/6; for (j = dim*(dim-1)+1; j dim*dim-1; j+) dstj.red = (srcj.red+srcj-1.red+srcj+1.red+srcj-dim.red+srcj+1-dim.red+srcj-1-dim.red)/6; dstj.green = (srcj.green+srcj-1.green+srcj+1.green+srcj-dim.green+srcj+1-dim.green+srcj-1-dim.green)/6; dstj.blue = (srcj.blue+srcj-1.blue+srcj+1.blue+srcj-dim.blue+srcj+1-dim.blue+srcj-1-dim.blue)/6; for (j = dim; j dim*(dim-1); j+=dim) dstj.red = (srcj.red+srcj-dim.red+srcj+1.red+srcj+dim.red+srcj+1+dim.red+srcj-dim+1.red)/6; dstj.green = (srcj.green+srcj-dim.green+srcj+1.green+srcj+dim.green+srcj+1+dim.green+srcj-dim+1.green)/6; dstj.blue = (srcj.blue+srcj-dim.blue+srcj+1.blue+srcj+dim.blue+srcj+1+dim.blue+srcj-dim+1.blue)/6; for (j = dim+dim-1; j dim*dim-1; j+=d