primes.pir

# Copyright (C) 2001-2009, Parrot Foundation.

=head1 NAME

examples/benchmarks/primes.pasm - Calculate prime numbers < 5000

=head1 SYNOPSIS

% time ./parrot examples/benchmarks/primes.pasm

=head1 DESCRIPTION

Calculates all the prime numbers up to 5000 and prints out the number
of primes, the last one found, and the time taken.

=cut

.loadlib 'math_ops' # cmod is a dynop

.sub 'main' :main

# P1 holds the number we're currently checking for primality
new     $P1, 'Integer'
set     $P1, 1

# P2 holds the highest number we want to check for primality
new     $P2, 'Integer'
set     $P2, 17619

new     $P6, 'Integer'
set     $P6, 0
new     $P7, 'Integer'

print   "N primes up to "
print   $P2
print   " is: "
time    $N10

# P1 counts up to P2
# P3 counts from 2 up to P4 (P1/2)
new     $P3, 'Integer'

REDO:
set     $P3, 2
div     $P4, $P1, 2
# Check if P3 is a factor of P1
LOOP:
cmod    $P5, $P1, $P3
if      $P5, OK

# We've found a factor, so it can't be a prime and
    # we can skip right out of this loop and to the next number
    branch  NEXT
OK:
    inc     $P3
    le      $P3, $P4, LOOP
    # We haven't found a factor so it must be a prime
    inc     $P6
    assign  $P7, $P1
    # print I1
    # print "\n"    # to get them all

    # Move on to the next number
NEXT:
    inc     $P1
    le      $P1, $P2, REDO
    time    $N11
    say     $P6
    print   "last is: "
    say     $P7
    sub     $N11, $N10
    print   "Elapsed time: "
    say     $N11
.end

=head1 SEE ALSO

F<examples/benchmarks/primes.c>,
F<examples/benchmarks/primes_i.pasm>,
F<examples/benchmarks/primes.pl>,
F<examples/benchmarks/primes.rb>,
F<examples/benchmarks/primes2_p.pasm>,
F<examples/benchmarks/primes2.c>,
F<examples/benchmarks/primes2.pir>,
F<examples/benchmarks/primes2.py>.

=cut

# Local Variables:
#   mode: pir
#   fill-column: 100
# End:
# vim: expandtab shiftwidth=4 ft=pir: