From 3d3083b91f02ca14acddde97612cec98e97ffe38 Mon Sep 17 00:00:00 2001 From: Jackson Tian Date: Thu, 16 Apr 2015 11:29:02 +0800 Subject: [PATCH] buffer: little improve for Buffer.concat method When buffer list less than 2, no need to calculate the length. The change's benchmark result is here: https://gist.github.com/JacksonTian/2c9e2bdec00018e010e6 It improve 15% ~ 25% speed when list only have one buffer, to other cases no effect. PR-URL: https://github.com/iojs/io.js/pull/1437 Reviewed-By: Trevor Norris Reviewed-By: Brendan Ashworth --- lib/buffer.js | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/lib/buffer.js b/lib/buffer.js index 8f4e34d289f..dc2b656d7a7 100644 --- a/lib/buffer.js +++ b/lib/buffer.js @@ -247,6 +247,11 @@ Buffer.concat = function(list, length) { if (!Array.isArray(list)) throw new TypeError('list argument must be an Array of Buffers.'); + if (list.length === 0) + return new Buffer(0); + else if (list.length === 1) + return list[0]; + if (length === undefined) { length = 0; for (var i = 0; i < list.length; i++) @@ -255,11 +260,6 @@ Buffer.concat = function(list, length) { length = length >>> 0; } - if (list.length === 0) - return new Buffer(0); - else if (list.length === 1) - return list[0]; - var buffer = new Buffer(length); var pos = 0; for (var i = 0; i < list.length; i++) {