# Copyright (C) 2001-2008, Parrot Foundation.
# $Id: fib.pir 37201 2009-03-08 12:07:48Z fperrad $

=head1 NAME

examples/benchmarks/fib.pir - Fibonacci Benchmark

=head1 SYNOPSIS

    % time ./parrot examples/benchmarks/fib.pir n

=head1 DESCRIPTION

Calculates the Fibonacci Number for C<n> (defaults to 28 if
unspecified).

=cut

.sub _main
    .param pmc argv
    .local int argc
    argc = argv
    .local int N
    N = 28
    if argc <= 1 goto noarg
    $S0 = argv[1]
    N = $S0
noarg:
    .local num start
    .local pmc fib
    .local int r
    time start
    r = _fib(N)
    .local num fin
    time fin
    print "fib("
    print N
    print ") = "
    print r
    print " "
    fin -= start
    print fin
    print "s\n"
    end
.end

.sub _fib
    .param int n
    if n < 2 goto ret
    .local int n1, n2, r1, r2
    n1 = n - 1
    n2 = n - 2
    r1 = _fib(n1)
    r2 = _fib(n2)
    n = r1 + r2
ret:
    .return (n)
.end

=head1 SEE ALSO

F<examples/benchmarks/fib.pl>.

=cut

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