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in reply to Re^5: High Performance Game of Life
in thread High Performance Game of Life

Thanks Mario! Shaved a couple more seconds:

See "Mario improvements" entries in "Benchmark Results" section of root node for speed comparison with original Organism.pm.

package Organism; use strict; sub count { scalar keys %{ shift->{Cells} } } # Input a list of [ x, y ] coords sub insert_cells { my $cells = shift->{Cells}; for my $r (@_) { $cells->{ pack 'i2', @{$r} } = undef } } # Return sorted list of cells in the Organism. # Used for verification and testing the state of the organism. sub get_live_cells { sort { $a->[0] <=> $b->[0] || $a->[1] <=> $b->[1] } map { [ unpack 'i2', $_ ] } keys %{ shift->{Cells} }; } sub tick { my $self = shift; my $cells = $self->{Cells}; my ( $k1, $k2, $k3, $k4, $k5, $k6, $k7, $k8, $x0, $x1, $x2, $y0, $y1, $y2, %newcells ); for my $c (keys %{ $cells }) { # Get the (up to 8) dead cells surrounding the cell ( $x0, $y0 ) = unpack 'i2', $c; ( $x1, $x2, $y1, $y2 ) = ( $x0 - 1, $x0 + 1, $y0 - 1, $y0 + 1 ); my @zcells = ( ($k1 = pack 'i2', $x1, $y1) x !exists($cells->{$k1}), ($k2 = pack 'i2', $x1, $y0) x !exists($cells->{$k2}), ($k3 = pack 'i2', $x1, $y2) x !exists($cells->{$k3}), ($k4 = pack 'i2', $x0, $y1) x !exists($cells->{$k4}), ($k5 = pack 'i2', $x0, $y2) x !exists($cells->{$k5}), ($k6 = pack 'i2', $x2, $y1) x !exists($cells->{$k6}), ($k7 = pack 'i2', $x2, $y0) x !exists($cells->{$k7}), ($k8 = pack 'i2', $x2, $y2) x !exists($cells->{$k8}) ); # Check the live cell (next line equivalent to nlive==2 || nlive +==3) @zcells == 5 || @zcells == 6 and $newcells{$c} = undef; # Check the dead cells for my $z (@zcells) { ( $x0, $y0 ) = unpack 'i2', $z; ( $x1, $x2, $y1, $y2 ) = ( $x0 - 1, $x0 + 1, $y0 - 1, $y0 + 1 + ); exists($cells->{pack 'i2', $x1, $y1}) + exists($cells->{pack 'i2', $x1, $y0}) + exists($cells->{pack 'i2', $x1, $y2}) + exists($cells->{pack 'i2', $x0, $y1}) + exists($cells->{pack 'i2', $x0, $y2}) + exists($cells->{pack 'i2', $x2, $y1}) + exists($cells->{pack 'i2', $x2, $y0}) + exists($cells->{pack 'i2', $x2, $y2}) == 3 and $newcells{$z +} = undef; } } $self->{Cells} = \%newcells; } sub new { my $class = shift; my %init_self = ( Cells => {} ); bless \%init_self, $class; } 1;

Update: Minor stylistic edits were made to Organism.pm above. Note that changing the main loop above from:

for my $c (keys %{ $cells }) {
to:
while ( my ($c) = each %{ $cells } ) {
uses less memory - though I couldn't measure any difference in speed.

Update: This one is shorter, but a bit slower:

sub tick { my $self = shift; my $cells = $self->{Cells}; my ( $k1, $k2, $k3, $k4, $k5, $k6, $k7, $k8, $x0, $x1, $x2, $y0, $y1, $y2 ); %{$cells} = map { ( $x0, $y0 ) = unpack 'i2', $_; ( $x1, $x2, $y1, $y2 ) = ( $x0 - 1, $x0 + 1, $y0 - 1, $y0 + 1 ); my @zcells = ( ($k1 = pack 'i2', $x1, $y1) x !exists($cells->{$k1}), ($k2 = pack 'i2', $x1, $y0) x !exists($cells->{$k2}), ($k3 = pack 'i2', $x1, $y2) x !exists($cells->{$k3}), ($k4 = pack 'i2', $x0, $y1) x !exists($cells->{$k4}), ($k5 = pack 'i2', $x0, $y2) x !exists($cells->{$k5}), ($k6 = pack 'i2', $x2, $y1) x !exists($cells->{$k6}), ($k7 = pack 'i2', $x2, $y0) x !exists($cells->{$k7}), ($k8 = pack 'i2', $x2, $y2) x !exists($cells->{$k8}) ); ($_, undef) x (@zcells == 5 || @zcells == 6), map { ( $x0, $y0 ) = unpack 'i2', $_; ( $x1, $x2, $y1, $y2 ) = ( $x0 - 1, $x0 + 1, $y0 - 1, $y0 + +1 ); ($_, undef) x ( exists($cells->{pack 'i2', $x1, $y1}) + exists($cells->{pack 'i2', $x1, $y0}) + exists($cells->{pack 'i2', $x1, $y2}) + exists($cells->{pack 'i2', $x0, $y1}) + exists($cells->{pack 'i2', $x0, $y2}) + exists($cells->{pack 'i2', $x2, $y1}) + exists($cells->{pack 'i2', $x2, $y0}) + exists($cells->{pack 'i2', $x2, $y2}) == 3 ) } @zcells } keys %{$cells}; }
as is this one:
sub tick { my $self = shift; my $cells = $self->{Cells}; my ( $k1, $k2, $k3, $k4, $k5, $k6, $k7, $k8, $x0, $x1, $x2, $y0, $y1, $y2 ); my %newcells; @newcells{map { ( $x0, $y0 ) = unpack 'i2', $_; ( $x1, $x2, $y1, $y2 ) = ( $x0 - 1, $x0 + 1, $y0 - 1, $y0 + 1 ); my @zcells = ( ($k1 = pack 'i2', $x1, $y1) x !exists($cells->{$k1}), ($k2 = pack 'i2', $x1, $y0) x !exists($cells->{$k2}), ($k3 = pack 'i2', $x1, $y2) x !exists($cells->{$k3}), ($k4 = pack 'i2', $x0, $y1) x !exists($cells->{$k4}), ($k5 = pack 'i2', $x0, $y2) x !exists($cells->{$k5}), ($k6 = pack 'i2', $x2, $y1) x !exists($cells->{$k6}), ($k7 = pack 'i2', $x2, $y0) x !exists($cells->{$k7}), ($k8 = pack 'i2', $x2, $y2) x !exists($cells->{$k8}) ); ($_) x (@zcells == 5 || @zcells == 6), map { ( $x0, $y0 ) = unpack 'i2', $_; ( $x1, $x2, $y1, $y2 ) = ( $x0 - 1, $x0 + 1, $y0 - 1, $y0 + +1 ); ($_) x ( exists($cells->{pack 'i2', $x1, $y1}) + exists($cells->{pack 'i2', $x1, $y0}) + exists($cells->{pack 'i2', $x1, $y2}) + exists($cells->{pack 'i2', $x0, $y1}) + exists($cells->{pack 'i2', $x0, $y2}) + exists($cells->{pack 'i2', $x2, $y1}) + exists($cells->{pack 'i2', $x2, $y0}) + exists($cells->{pack 'i2', $x2, $y2}) == 3 ) } @zcells } keys %{$cells} } = undef; $self->{Cells} = \%newcells; }
I'm guessing they are slower because the list of cells used in the hash slice contains many duplicate dead cells.

Update: Changing:

my @zcells = ( ($k1 = pack 'i2', $x1, $y1) x !exists($cells->{$k1}), ($k2 = pack 'i2', $x1, $y0) x !exists($cells->{$k2}), ($k3 = pack 'i2', $x1, $y2) x !exists($cells->{$k3}), ($k4 = pack 'i2', $x0, $y1) x !exists($cells->{$k4}), ($k5 = pack 'i2', $x0, $y2) x !exists($cells->{$k5}), ($k6 = pack 'i2', $x2, $y1) x !exists($cells->{$k6}), ($k7 = pack 'i2', $x2, $y0) x !exists($cells->{$k7}), ($k8 = pack 'i2', $x2, $y2) x !exists($cells->{$k8}) );
to:
my @zcells = grep( !exists($cells->{$_}), pack('i2', $x1, $y1), pack('i2', $x1, $y0), pack('i2', $x1, $y2), pack('i2', $x0, $y1), pack('i2', $x0, $y2), pack('i2', $x2, $y1), pack('i2', $x2, $y0), pack('i2', $x2, $y2) );
was slightly slower.

This one was also slower:

sub tick { my $self = shift; my $cells = $self->{Cells}; my ( $k1, $k2, $k3, $k4, $k5, $k6, $k7, $k8, $x0, $x1, $x2, $y0, $y1, $y2, $z, %newcells ); for my $c (keys %{ $cells }) { # Get the (up to 8) dead cells surrounding the cell ( $x0, $y0 ) = unpack 'i2', $c; ( $x1, $x2, $y1, $y2 ) = ( $x0 - 1, $x0 + 1, $y0 - 1, $y0 + 1 ); my @zcells = ( ($x1, $y1, $k1 = pack 'i2', $x1, $y1) x !exists($cells->{$k1} +), ($x1, $y0, $k2 = pack 'i2', $x1, $y0) x !exists($cells->{$k2} +), ($x1, $y2, $k3 = pack 'i2', $x1, $y2) x !exists($cells->{$k3} +), ($x0, $y1, $k4 = pack 'i2', $x0, $y1) x !exists($cells->{$k4} +), ($x0, $y2, $k5 = pack 'i2', $x0, $y2) x !exists($cells->{$k5} +), ($x2, $y1, $k6 = pack 'i2', $x2, $y1) x !exists($cells->{$k6} +), ($x2, $y0, $k7 = pack 'i2', $x2, $y0) x !exists($cells->{$k7} +), ($x2, $y2, $k8 = pack 'i2', $x2, $y2) x !exists($cells->{$k8} +) ); # Check the live cell (next line equivalent to nlive==2 || nlive +==3) @zcells == 15 || @zcells == 18 and $newcells{$c} = undef; # Check the dead cells while (@zcells) { ( $x0, $y0, $z ) = splice @zcells, 0, 3; ( $x1, $x2, $y1, $y2 ) = ( $x0 - 1, $x0 + 1, $y0 - 1, $y0 + 1 + ); exists($cells->{pack 'i2', $x1, $y1}) + exists($cells->{pack 'i2', $x1, $y0}) + exists($cells->{pack 'i2', $x1, $y2}) + exists($cells->{pack 'i2', $x0, $y1}) + exists($cells->{pack 'i2', $x0, $y2}) + exists($cells->{pack 'i2', $x2, $y1}) + exists($cells->{pack 'i2', $x2, $y0}) + exists($cells->{pack 'i2', $x2, $y2}) == 3 and $newcells{$z +} = undef; } } $self->{Cells} = \%newcells; }