The tests are a little ignorant to say the least. In the comments the author says it was important "to see how the same code executed in each language", but the code itself is quite poor and could easily optimized in half a dozen spots (pre-compute array lengths, pre-increment rather than post-increment, actually run bubble sort more than once).
Secondly, the sort function only runs once, and then just does nothing 99,999 times. My guess is the V8 JIT and the GO compiler realize this and optimize it out. Since PHP is interpreted it's shit out of luck.
