--- /dev/null
+public class MatrixMultiply extends Thread{
+ MMul mmul;
+ public int x0, y0, x1, y1;
+
+ public MatrixMultiply(MMul mmul, int x0, int y0, int x1, int y1) {
+ this.mmul = mmul;
+ this.x0 = x0;
+ this.y0 = y0;
+ this.x1 = x1;
+ this.y1 = y1;
+ }
+
+ public void run() {
+ int localresults[][];
+
+ //compute the results
+ localresults=new int[1+x1-x0][1+y1-y0];
+
+ //Use b transpose for cache performance
+ for(int i = x0; i<= x1; i++){
+ int a[]=mmul.a[i];
+ int M=mmul.M;
+ for (int j = y0; j <= y1; j++) {
+ int innerProduct=0;
+ int b[] = mmul.btranspose[j];
+ for(int k = 0; k < M; k++) {
+ innerProduct += a[k] *b[k];
+ }
+ localresults[i-x0][j-y0]=innerProduct;
+ }
+ }
+
+ //write the results
+ for(int i=x0;i<=x1;i++) {
+ int c[]=mmul.c[i];
+ for(int j=y0;j<=y1;j++) {
+ c[j]=localresults[i-x0][j-y0];
+ }
+ }
+ }
+
+ public static void main(String[] args) {
+ int NUM_THREADS = 1;
+ int p, q, r;
+ MatrixMultiply[] mm;
+ MatrixMultiply tmp;
+ MMul matrix;
+
+ matrix = new MMul(400, 400, 400);
+ matrix.setValues();
+ matrix.transpose();
+
+ mm = new MatrixMultiply[NUM_THREADS];
+ mm[0] = new MatrixMultiply(matrix,0,0,399,399);
+
+ p = matrix.L;
+ q = matrix.M;
+ r = matrix.N;
+
+ // print out the matrices to be multiplied
+ System.out.print("MatrixMultiply: L=");
+ System.out.print(p);
+ System.out.print("\t");
+ System.out.print("M=");
+ System.out.print(q);
+ System.out.print("\t");
+ System.out.print("N=");
+ System.out.print(r);
+ System.out.print("\n");
+
+ // start a thread to compute each c[l,n]
+ for (int i = 0; i < NUM_THREADS; i++) {
+ tmp = mm[i];
+ tmp.start();
+ }
+
+ // wait for them to finish
+ for (int i = 0; i < NUM_THREADS; i++) {
+ try {
+ mm[i].join();
+ } catch (InterruptedException e) {
+ System.out.println("Join Error");
+ }
+
+ }
+
+ // print out the result of the matrix multiply
+ System.out.println("Starting\n");
+ System.out.println("Matrix Product c =\n");
+ int val;
+ for (int i = 0; i < p; i++) {
+ int c[]=matrix.c[i];
+ for (int j = 0; j < r; j++) {
+ val = c[j];
+ }
+ }
+ System.out.println("Finished\n");
+ }
+}
+
+class MMul{
+
+ public int L, M, N;
+ public int[][] a;
+ public int[][] b;
+ public int[][] c;
+ public int[][] btranspose;
+
+ public MMul(int L, int M, int N) {
+ this.L = L;
+ this.M = M;
+ this.N = N;
+ a = new int[L][M];
+ b = new int[M][N];
+ c = new int[L][N];
+ btranspose = new int[N][M];
+ }
+
+ public void setValues() {
+ for(int i = 0; i < L; i++) {
+ int ai[] = a[i];
+ for(int j = 0; j < M; j++) {
+ ai[j] = j+1;
+ }
+ }
+
+ for(int i = 0; i < M; i++) {
+ int bi[] = b[i];
+ for(int j = 0; j < N; j++) {
+ bi[j] = j+1;
+ }
+ }
+
+ for(int i = 0; i < L; i++) {
+ int ci[] = c[i];
+ for(int j = 0; j < N; j++) {
+ ci[j] = 0;
+ }
+ }
+ for(int i = 0; i < N; i++) {
+ int btransposei[] = btranspose[i];
+ for(int j = 0; j < M; j++) {
+ btransposei[j] = 0;
+ }
+ }
+ }
+
+ public void transpose() {
+ for(int row = 0; row < M; row++) {
+ int brow[] = b[row];
+ for(int col = 0; col < N; col++) {
+ btranspose[col][row] = brow[col];
+ }
+ }
+ }
+}