From a3dee0695db8de07eec4ca6ffad6f46bcb82b499 Mon Sep 17 00:00:00 2001
From: Braydon Fuller <braydon@bitpay.com>
Date: Fri, 26 Jun 2015 14:02:26 -0400
Subject: [PATCH] Improved performance of bufferReader.readUInt64LEBN()

---
 benchmark/serialization.js   | 39 ++++++++++++++++++++++++++++++++++++
 lib/encoding/bufferreader.js |  7 ++-----
 2 files changed, 41 insertions(+), 5 deletions(-)

diff --git a/benchmark/serialization.js b/benchmark/serialization.js
index 7b45cc7..d0024bd 100644
--- a/benchmark/serialization.js
+++ b/benchmark/serialization.js
@@ -14,6 +14,45 @@ console.log('Benchmarking Block/Transaction Serialization');
 console.log('---------------------------------------');
 
 async.series([
+  function(next) {
+
+    var buffers = [];
+    console.log('Generating Random Test Data...');
+    for (var i = 0; i < 100; i++) {
+      var br = new bitcore.encoding.BufferWriter();
+      var num = Math.round(Math.random() * 10000000000000);
+      br.writeUInt64LEBN(new bitcore.crypto.BN(num));
+      buffers.push(br.toBuffer());
+    }
+
+    var c = 0;
+    var bn;
+
+    function readUInt64LEBN() {
+      if (c >= buffers.length) {
+        c = 0;
+      }
+      var buf = buffers[c];
+      var br = new bitcore.encoding.BufferReader(buf);
+      bn = br.readUInt64LEBN();
+      c++;
+    }
+
+    console.log('Starting benchmark...');
+
+    var suite = new benchmark.Suite();
+    suite.add('bufferReader.readUInt64LEBN()', readUInt64LEBN, {maxTime: maxTime});
+    suite
+      .on('cycle', function(event) {
+        console.log(String(event.target));
+      })
+      .on('complete', function() {
+        console.log('Done');
+        console.log('----------------------------------------------------------------------');
+        next();
+      })
+      .run();
+  },
   function(next) {
 
     var block1;
diff --git a/lib/encoding/bufferreader.js b/lib/encoding/bufferreader.js
index bb881fb..19c6f81 100644
--- a/lib/encoding/bufferreader.js
+++ b/lib/encoding/bufferreader.js
@@ -91,11 +91,8 @@ BufferReader.prototype.readUInt64BEBN = function() {
 };
 
 BufferReader.prototype.readUInt64LEBN = function() {
-  var buf = this.buf.slice(this.pos, this.pos + 8);
-  var reversebuf = BufferReader({
-    buf: buf
-  }).readReverse();
-  var bn = BN.fromBuffer(reversebuf);
+  var data = this.buf.slice(this.pos, this.pos + 8).toJSON().data;
+  var bn = new BN(data, 10, 'le');
   this.pos = this.pos + 8;
   return bn;
 };