#!/usr/bin/perl -wl
use strict;

use Inline C => Config =>
           LDDLFLAGS => '-shared ../../../popcount.o';
use Inline "C";
use Benchmark "cmpthese";

my $s = pack "C*", map { int rand 256 } 1 .. 2**18;  # 256k

#print unpack q/%32b*/, $s;
#print count_bits($s);

cmpthese (-2, {
    unpack => sub { my $n = unpack q/%32b*/, $s; },
    popcnt => sub { my $n = count_bits($s); },
});

__END__
__C__
extern unsigned long popcount(char *, int64_t);  // the asm routine

unsigned long count_bits (SV* bitstr) {  // XS wrapper
    STRLEN l;
    char *s = SvPV(bitstr, l);
    return popcount(s, l);
}