CSC/ECE 506 Spring 2010/ch 3 yl
Supplement to Chapter 3: Support for parallel-programming models. Discuss how DOACROSS, DOPIPE, DOALL, etc. are implemented in packages such as Posix threads, Intel Thread Building Blocks, OpenMP 2.0 and 3.0.
Parallel-programming models
DOALL
for i:=2:N-1 do A(i):=[A(i-1) + A(i) + A(i+1)]/3; next i; forall i:=2:N-1 do A(i):=[A(i-1) + A(i) + A(i+1)]/3;
for (i=2; i<=n; i+=2) s: a[i] = a[i-2]; for (i=3; i<=n; i+=2) s: a[i] = a[i-2];
switch (n) {
case 0:
puts("You typed zero.");
break;
case 1:
case 9:
puts("n is a perfect square.");
break;
case 2:
puts("n is an even number.");
case 3:
case 5:
case 7:
puts("n is a prime number.");
break;
case 4:
puts("n is a perfect square.");
case 6:
case 8:
puts("n is an even number.");
break;
default:
puts("Only single-digit numbers are allowed.");
break;
}
DOACROSS
for i:=2:N-1 do A(i):=[A(i-1) + A(i) + A(i+1)]/3; next i; forall i:=2:N-1 do A(i):=[A(i-1) + A(i) + A(i+1)]/3;
for (i=1; i<=N; i++) {
S: a[i] = a[i-1] + b[i] * c[i];
}
for (i=1; i<=N; i++) {
S1: temp[i] = b[i] * c[i];
}
for (i=1; i<=N; i++) {
S2: a[i] = a[i-1] + temp[i];
}