[PHP实现JavaScript的位移运算符] https://zhile.io/2018/06/21/php-equivalent-javascript-bitwise-operators.html #无符号右移 #位运算

右移.php

<?php

/**
 * >> javascript operator in php x86_64
 * @param int $v
 * @param int $n
 * @return int
 */
function rr($v, $n)
{
  $v = $v & 0x80000000 ? $v | 0xFFFFFFFF00000000 : $v & 0xFFFFFFFF;

  return $v >> ($n & 0x1F);
}

左移.php

<?php

/**
 * << javascript operator in php x86_64
 * @param int $v
 * @param int $n
 * @return int
 */
function ll($v, $n)
{
  $t = ($v & 0xFFFFFFFF) << ($n & 0x1F);

  return $t & 0x80000000 ? $t | 0xFFFFFFFF00000000 : $t & 0xFFFFFFFF;
}

无符号右移.php

<?php

/**
 * >>> javascript operator in php x86_64
 * @param int $v
 * @param int $n
 * @return int
 */
function rrr($v, $n)
{
  return ($v & 0xFFFFFFFF) >> ($n & 0x1F);
}

附送一个PHP对javascript逗号运算符（,）的模拟.php

// 转换效果（js to PHP）：
// if (i = 0, j = 1, k =2) {} to if (comma($i = 0, $j = 1, $k = 2)) {}


/**
 * @param ...
 * @return mixed
 */
function comma()
{
  $args = func_get_args();
  return end($args);
}