From d13aba84996f576fab9c597209fb228518ed2e46 Mon Sep 17 00:00:00 2001
From: Brian White <mscdex@mscdex.net>
Date: Thu, 19 Jan 2017 22:26:18 -0500
Subject: [PATCH] buffer: improve compare() performance
PR-URL: https://github.com/nodejs/node/pull/10927
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: James M Snell <jasnell@gmail.com>
---
.../buffers/buffer-compare-instance-method.js | 72 ++++++++++++++++---
lib/buffer.js | 40 ++++++-----
2 files changed, 87 insertions(+), 25 deletions(-)
diff --git a/benchmark/buffers/buffer-compare-instance-method.js b/benchmark/buffers/buffer-compare-instance-method.js
index 0becbeee23a7d7..bb07326f3de218 100644
--- a/benchmark/buffers/buffer-compare-instance-method.js
+++ b/benchmark/buffers/buffer-compare-instance-method.js
@@ -4,26 +4,80 @@ const v8 = require('v8');
const bench = common.createBenchmark(main, {
size: [16, 512, 1024, 4096, 16386],
+ args: [1, 2, 3, 4, 5],
millions: [1]
});
function main(conf) {
const iter = (conf.millions >>> 0) * 1e6;
const size = (conf.size >>> 0);
- const b0 = new Buffer(size).fill('a');
- const b1 = new Buffer(size).fill('a');
+ const args = (conf.args >>> 0);
+ const b0 = Buffer.alloc(size, 'a');
+ const b1 = Buffer.alloc(size, 'a');
+ const b0Len = b0.length;
+ const b1Len = b1.length;
+ var i;
b1[size - 1] = 'b'.charCodeAt(0);
// Force optimization before starting the benchmark
- b0.compare(b1);
+ switch (args) {
+ case 2:
+ b0.compare(b1, 0);
+ break;
+ case 3:
+ b0.compare(b1, 0, b1Len);
+ break;
+ case 4:
+ b0.compare(b1, 0, b1Len, 0);
+ break;
+ case 5:
+ b0.compare(b1, 0, b1Len, 0, b0Len);
+ break;
+ default:
+ b0.compare(b1);
+ }
v8.setFlagsFromString('--allow_natives_syntax');
eval('%OptimizeFunctionOnNextCall(b0.compare)');
- b0.compare(b1);
-
- bench.start();
- for (var i = 0; i < iter; i++) {
- b0.compare(b1);
+ switch (args) {
+ case 2:
+ b0.compare(b1, 0);
+ bench.start();
+ for (i = 0; i < iter; i++) {
+ b0.compare(b1, 0);
+ }
+ bench.end(iter / 1e6);
+ break;
+ case 3:
+ b0.compare(b1, 0, b1Len);
+ bench.start();
+ for (i = 0; i < iter; i++) {
+ b0.compare(b1, 0, b1Len);
+ }
+ bench.end(iter / 1e6);
+ break;
+ case 4:
+ b0.compare(b1, 0, b1Len, 0);
+ bench.start();
+ for (i = 0; i < iter; i++) {
+ b0.compare(b1, 0, b1Len, 0);
+ }
+ bench.end(iter / 1e6);
+ break;
+ case 5:
+ b0.compare(b1, 0, b1Len, 0, b0Len);
+ bench.start();
+ for (i = 0; i < iter; i++) {
+ b0.compare(b1, 0, b1Len, 0, b0Len);
+ }
+ bench.end(iter / 1e6);
+ break;
+ default:
+ b0.compare(b1);
+ bench.start();
+ for (i = 0; i < iter; i++) {
+ b0.compare(b1);
+ }
+ bench.end(iter / 1e6);
}
- bench.end(iter / 1e6);
}
diff --git a/lib/buffer.js b/lib/buffer.js
index fa8d1c61d4a309..299b9bc01177be 100644
--- a/lib/buffer.js
+++ b/lib/buffer.js
@@ -2,6 +2,7 @@
'use strict';
const binding = process.binding('buffer');
+const { compare: compare_, compareOffset } = binding;
const { isArrayBuffer, isSharedArrayBuffer } = process.binding('util');
const bindingObj = {};
const internalUtil = require('internal/util');
@@ -537,36 +538,43 @@ Buffer.prototype.compare = function compare(target,
if (!(target instanceof Buffer))
throw new TypeError('Argument must be a Buffer');
+ if (arguments.length === 1)
+ return compare_(this, target);
if (start === undefined)
start = 0;
+ else if (start < 0)
+ throw new RangeError('out of range index');
+ else
+ start >>>= 0;
+
if (end === undefined)
end = target.length;
+ else if (end > target.length)
+ throw new RangeError('out of range index');
+ else
+ end >>>= 0;
+
if (thisStart === undefined)
thisStart = 0;
+ else if (thisStart < 0)
+ throw new RangeError('out of range index');
+ else
+ thisStart >>>= 0;
+
if (thisEnd === undefined)
thisEnd = this.length;
-
- if (start < 0 ||
- end > target.length ||
- thisStart < 0 ||
- thisEnd > this.length) {
+ else if (thisEnd > this.length)
throw new RangeError('out of range index');
- }
+ else
+ thisEnd >>>= 0;
- if (thisStart >= thisEnd && start >= end)
- return 0;
if (thisStart >= thisEnd)
- return -1;
- if (start >= end)
+ return (start >= end ? 0 : -1);
+ else if (start >= end)
return 1;
- start >>>= 0;
- end >>>= 0;
- thisStart >>>= 0;
- thisEnd >>>= 0;
-
- return binding.compareOffset(this, target, start, thisStart, end, thisEnd);
+ return compareOffset(this, target, start, thisStart, end, thisEnd);
};