From: mame@... Date: 2019-02-07T01:07:13+00:00 Subject: [ruby-core:91444] [Ruby trunk Bug#15589] `Numeric#zero?` is much slower than `== 0` Issue #15589 has been updated by mame (Yusuke Endoh). sawa (Tsuyoshi Sawada) wrote: > So I think there are two ways to go. One: Acknowledge that there are uses for these methods, and optimize them, or Two: Make them obsolete, in which case the original use cases should use `== 0`. Don't be extreme. Both "One" and "Two" is unreasonable to me. My "Three": Let it be. Speed consistency is a too weak reason to do anything. Eregon (Benoit Daloze) wrote: > If zero? was written in Ruby (like it is in Rubinius & TruffleRuby), and Ruby inlining was implemented (TruffleRuby does), then there should be very little difference once #zero? is compiled by the JIT. I think that this is the way to go. So I assigned this to k0kubun. (I think the priority is very low, though.) ---------------------------------------- Bug #15589: `Numeric#zero?` is much slower than `== 0` https://bugs.ruby-lang.org/issues/15589#change-76703 * Author: sawa (Tsuyoshi Sawada) * Status: Open * Priority: Normal * Assignee: k0kubun (Takashi Kokubun) * Target version: * ruby -v: 2.6.1 * Backport: 2.4: UNKNOWN, 2.5: UNKNOWN, 2.6: UNKNOWN ---------------------------------------- My understanding is that the predicate method `Numeric#zero?` is not only a shorthand for `== 0`, but is also optimized for frequent patterns. If `zero?` is not faster than `== 0`, then it loses its reason for existence. However, According to benchmarks on my environment, `number.zero?` is around 1.23 times to 1.64 times slower than `number == 0` when `number` is an `Integer`, `Rational`, or `Complex`. It is faster only when `number` is a `Float`. And with `number.nonzero?`, it is even worse. It is about 1.88 times to 4.35 times slower than `number != 0`. I think there is something wrong with this, and it should be possible to optimize these methods, which has somehow been missed. -- https://bugs.ruby-lang.org/ Unsubscribe: