Introduction to Concurrency in Programming Languages

Pattern: Data Parallelism 243

Listing 11.5: Binary thresholding.

int x [ m ][n ];

int i , j ;

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

for ( j =0; j <n ; j ++)

if ( x [i ][j ] < t)

x[i ][ j] = 0;

else

x[i ][ j] = 1;

in the function invocation. Another approach is to use languages that pro-

vide syntax for invoking these small functions (often called kernels) over the

whole array using specialized syntax. New language extensions such as CUDA

and OpenCL provide tools for programmers to do these types of operations.

Unfortunately, these languages are nearly as concise as those that provide

elemental functions and often require the programmer to do many low-level

operations to ...