{ # has use integer/bytes 

	use integer;
        use bytes; 

# http://www.perlmonks.org/?node_id=315881
# http://burtleburtle.net/bob/c/lookup2.c
# http://burtleburtle.net/bob/hash/doobs.html
# http://search.cpan.org/~shlomif/Digest-JHash/lib/Digest/JHash.pm
# http://cpansearch.perl.org/src/SHLOMIF/Digest-JHash-0.10/JHash.xs */ 

use constant GOLDEN_RATIO	=> 0x9e3779b9;

use constant A          => 0;
use constant B          => 1;
use constant C          => 2;
use constant FFFFFFFF   => 0xffffffff; 
use constant KEY	=> 0;
use constant INITHASH	=> 1;

sub mix4 ($$$) {
# 32bit version 
# per http://www.perlmonks.org/?node_id=1203705 this is a revised 32bit under 'use integer'; 
	$_[A] -= $_[B]; $_[A] -= $_[C]; { no integer; $_[A] ^= ($_[C]>>13); }
	$_[B] -= $_[C]; $_[B] -= $_[A]; { no integer; $_[B] ^= ($_[A]<< 8); } 
	$_[C] -= $_[A]; $_[C] -= $_[B]; { no integer; $_[C] ^= ($_[B]>>13); } 
	$_[A] -= $_[B]; $_[A] -= $_[C]; { no integer; $_[A] ^= ($_[C]>>12); } 
	$_[B] -= $_[C]; $_[B] -= $_[A]; { no integer; $_[B] ^= ($_[A]<<16); } 
	$_[C] -= $_[A]; $_[C] -= $_[B]; { no integer; $_[C] ^= ($_[B]>> 5); } 
	$_[A] -= $_[B]; $_[A] -= $_[C]; { no integer; $_[A] ^= ($_[C]>> 3); } 
	$_[B] -= $_[C]; $_[B] -= $_[A]; { no integer; $_[B] ^= ($_[A]<<10); } 
	$_[C] -= $_[A]; $_[C] -= $_[B]; { no integer; $_[C] ^= ($_[B]>>15); }
}

sub mix4x ($$$) {
# per http://www.perlmonks.org/?node_id=1203705 this is wrong 
	$_[A] -= $_[B]; $_[A] -= $_[C]; $_[A] ^= ($_[C]>>13);
	$_[B] -= $_[C]; $_[B] -= $_[A]; $_[B] ^= ($_[A]<< 8);
	$_[C] -= $_[A]; $_[C] -= $_[B]; $_[C] ^= ($_[B]>>13);
	$_[A] -= $_[B]; $_[A] -= $_[C]; $_[A] ^= ($_[C]>>12);
	$_[B] -= $_[C]; $_[B] -= $_[A]; $_[B] ^= ($_[A]<<16);
	$_[C] -= $_[A]; $_[C] -= $_[B]; $_[C] ^= ($_[B]>> 5);
	$_[A] -= $_[B]; $_[A] -= $_[C]; $_[A] ^= ($_[C]>> 3);
	$_[B] -= $_[C]; $_[B] -= $_[A]; $_[B] ^= ($_[A]<<10);
	$_[C] -= $_[A]; $_[C] -= $_[B]; $_[C] ^= ($_[B]>>15);
}


sub mix8 ($$$) {
# 64bit version 
        $_[A] &= FFFFFFFF; 
        $_[B] &= FFFFFFFF; 
        $_[C] &= FFFFFFFF; 

	$_[A] -= $_[B]; $_[A] -= $_[C]; $_[A] = ( $_[A] ^ ($_[C]>>13)  ) & FFFFFFFF;
	$_[B] -= $_[C]; $_[B] -= $_[A]; $_[B] = ( $_[B] ^ ($_[A]<< 8)  ) & FFFFFFFF;
	$_[C] -= $_[A]; $_[C] -= $_[B]; $_[C] = ( $_[C] ^ ($_[B]>>13)  ) & FFFFFFFF;
	$_[A] -= $_[B]; $_[A] -= $_[C]; $_[A] = ( $_[A] ^ ($_[C]>>12)  ) & FFFFFFFF;
	$_[B] -= $_[C]; $_[B] -= $_[A]; $_[B] = ( $_[B] ^ ($_[A]<<16)  ) & FFFFFFFF;
	$_[C] -= $_[A]; $_[C] -= $_[B]; $_[C] = ( $_[C] ^ ($_[B]>> 5)  ) & FFFFFFFF;  
	$_[A] -= $_[B]; $_[A] -= $_[C]; $_[A] = ( $_[A] ^ ($_[C]>> 3)  ) & FFFFFFFF; 
	$_[B] -= $_[C]; $_[B] -= $_[A]; $_[B] = ( $_[B] ^ ($_[A]<<10)  ) & FFFFFFFF; 
	$_[C] -= $_[A]; $_[C] -= $_[B]; $_[C] = ( $_[C] ^ ($_[B]>>15)  ) & FFFFFFFF; 
}


sub jhash_pp_hex {
	my ($a, $b, $c) = ( GOLDEN_RATIO, GOLDEN_RATIO, $_[INITHASH] );
	my ($p, $length) = (0, length $_[KEY]);
        my $len=$length; 
	my($x,$y,$z);
	while ($len>=12) {
		($x,$y,$z) = unpack 'LLL', substr($_[KEY], $p, 12);
                $a+=$x;$b+=$y;$c+=$z;  
		mix($a, $b, $c);
		$p += 12;
                $len-=12; 
	} 
#       even if len==0 we need another round to mix in the length 
        ($x,$y,$z) = unpack 'LLL', substr($_[KEY] . (chr(0)x12), $p, 12);
        $z<<=8;  # /* the first byte of c is reserved for the length */
        $z+=$length; 
        $a+=$x;$b+=$y;$c+=$z;  
        mix($a, $b, $c);

        my $hex = unpack("H*", pack("N", $c));
	return $hex;
} # jhash_pp_hex

  use Config; 
  if ( $Config{ivsize} == 4 ) { *main::mix=*main::mix4; } 
  else                        { *main::mix=*main::mix8; }

}  # has use integer/bytes  

print jhash_pp_hex('abcdef',0)."\n";