From 5a2357e551abe61cda4bf22019ea229d8ed0fb02 Mon Sep 17 00:00:00 2001
From: Peter Wu
Date: Sat, 26 Jul 2014 01:24:22 +0200
Subject: jsrrdgraph: Performance fix

commit 2a74a333ff143499b465234f0395a4aad7bdaa78 ("Upgrade to
javascriptrrd ver 1.1.1") converted getByteAt calls to a getEndianByteAt
call, but this also introduced a branch operation. Since endianess is
dependent on the file, we can move the switch_endian check outside the
function.

Performance improved from 0.148ms (n=336k) to .039ms (n=384k) which
translates to about 30 seconds!
---
 js/binaryXHR.js | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/js/binaryXHR.js b/js/binaryXHR.js
index 63186b3..6749273 100644
--- a/js/binaryXHR.js
+++ b/js/binaryXHR.js
@@ -63,12 +63,15 @@ function BinaryFile(strData, iDataOffset, iDataLength) {
 		throw new InvalidBinaryFile("Unsupported type " + (typeof strData));
 	}
 
-	this.getEndianByteAt = function(iOffset,width,delta) {
-		if (this.switch_endian)
-			return this.getByteAt(iOffset+width-delta-1);
-		else
-			return this.getByteAt(iOffset+delta);
-	};
+	if (switch_endian) {
+		this.getEndianByteAt = function(iOffset, width, delta) {
+			return this.getByteAt(iOffset + width - delta - 1);
+		};
+	} else {
+		this.getEndianByteAt = function(iOffset, width, delta) {
+			return this.getByteAt(iOffset + delta);
+		};
+	}
 
 	this.getLength = function() {
 		return dataLength;
-- 
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