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#! /usr/bin/env perl

# Copyright (C) 2021-2025 Guido Flohr <guido.flohr@cantanea.com>,
# all rights reserved.

# This program is free software. It comes without any warranty, to
# the extent permitted by applicable law. You can redistribute it
# and/or modify it under the terms of the Do What the Fuck You Want
# to Public License, Version 2, as published by Sam Hocevar. See
# http://www.wtfpl.net/ for more details.

use strict;
use integer;

use Test::More tests => 35;
use Chess::Plisco qw(:all);
# Macros from Chess::Plisco::Macro are already expanded here!

my ($bitboard, $count);

$bitboard = 0x88;
{ my $_b = $bitboard; for ($count = 0; $_b; ++$count) { $_b &= $_b - 1; } };
is $count, 2, 'popcount 0x88';
is $bitboard, 0x88, 'popcount 0x88';

$bitboard = 0xffff_ffff_ffff_ffff;
{ my $_b = $bitboard; for ($count = 0; $_b; ++$count) { $_b &= $_b - 1; } };
is $count, 64, 'popcount 0xffff_ffff_ffff_ffff';
is $bitboard, 0xffff_ffff_ffff_ffff, 'popcount 0xffff_ffff_ffff_ffff';

$bitboard = 0x1;
is((($bitboard) & -($bitboard)), 0x1,
	"cp_bitboard_clear_but_least_set($bitboard)");

$bitboard = 0x3;
is((($bitboard) & -($bitboard)), 0x1,
	"cp_bitboard_clear_but_least_set($bitboard)");

$bitboard = 0x7;
is((($bitboard) & -($bitboard)), 0x1,
	"cp_bitboard_clear_but_least_set($bitboard)");

$bitboard = 0xf;
is((($bitboard) & -($bitboard)), 0x1,
	"cp_bitboard_clear_but_least_set($bitboard)");

$bitboard = 0x7fff_ffff_ffff_ffff;
is((($bitboard) & -($bitboard)), 0x1,
	"cp_bitboard_clear_but_least_set($bitboard)");

$bitboard = 0x8fff_ffff_ffff_ffff;
is((($bitboard) & -($bitboard)), 0x1,
	"cp_bitboard_clear_but_least_set($bitboard)");

$bitboard = 0xffff_ffff_ffff_ffff;
is((($bitboard) & -($bitboard)), 0x1,
	"cp_bitboard_clear_but_least_set($bitboard)");

$bitboard = 0x2;
is((do {	my $A = $bitboard - 1 - ((($bitboard - 1) >> 1) & 0x5555_5555_5555_5555);	my $C = ($A & 0x3333_3333_3333_3333) + (($A >> 2) & 0x3333_3333_3333_3333);	my $n = $C + ($C >> 32);	$n = ($n & 0x0f0f0f0f) + (($n >> 4) & 0x0f0f0f0f);	$n = ($n & 0xff...
	"cp_bitboard_count_isolated_trailing_zbits($bitboard)");

$bitboard = 0x8000;
is((do {	my $A = $bitboard - 1 - ((($bitboard - 1) >> 1) & 0x5555_5555_5555_5555);	my $C = ($A & 0x3333_3333_3333_3333) + (($A >> 2) & 0x3333_3333_3333_3333);	my $n = $C + ($C >> 32);	$n = ($n & 0x0f0f0f0f) + (($n >> 4) & 0x0f0f0f0f);	$n = ($n & 0xff...
	"cp_bitboard_count_isolated_trailing_zbits($bitboard)");

$bitboard = 0x8000_0000_0000_0000;
is((do {	my $A = $bitboard - 1 - ((($bitboard - 1) >> 1) & 0x5555_5555_5555_5555);	my $C = ($A & 0x3333_3333_3333_3333) + (($A >> 2) & 0x3333_3333_3333_3333);	my $n = $C + ($C >> 32);	$n = ($n & 0x0f0f0f0f) + (($n >> 4) & 0x0f0f0f0f);	$n = ($n & 0xff...
	"cp_bitboard_count_isolated_trailing_zbits($bitboard)");

$bitboard = 0x1;
is((do {	my $A = $bitboard - 1 - ((($bitboard - 1) >> 1) & 0x5555_5555_5555_5555);	my $C = ($A & 0x3333_3333_3333_3333) + (($A >> 2) & 0x3333_3333_3333_3333);	my $n = $C + ($C >> 32);	$n = ($n & 0x0f0f0f0f) + (($n >> 4) & 0x0f0f0f0f);	$n = ($n & 0xff...
	"cp_bitboard_count_isolated_trailing_zbits($bitboard)");

$bitboard = 0x3;
is((($bitboard) & (($bitboard) - 1)), 0x2,
	"cp_bitboard_clear_least_set($bitboard)");