From 0e137c4d9e5c245424e78208a104fbc8b3aaee2a Mon Sep 17 00:00:00 2001 From: "Shawn O. Pearce" Date: Tue, 2 Feb 2010 14:21:27 -0800 Subject: [PATCH] Micro-optimize CanonicalTreeParser next() for ObjectWalk ObjectWalk is invoking next() for each record we consider in a tree. Rather than doing several method calls against the current parser, and testing if we are at eof() at least twice per next() invocation, do it only once and inline the logic to move the parser forward. Change-Id: If5938f5d7b3ca24f500a184c9bd2ef193015414e Signed-off-by: Shawn O. Pearce --- .../jgit/treewalk/CanonicalTreeParser.java | 22 ++++++++++++------- 1 file changed, 14 insertions(+), 8 deletions(-) diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/treewalk/CanonicalTreeParser.java b/org.eclipse.jgit/src/org/eclipse/jgit/treewalk/CanonicalTreeParser.java index 8a202035a..0b9dc0044 100644 --- a/org.eclipse.jgit/src/org/eclipse/jgit/treewalk/CanonicalTreeParser.java +++ b/org.eclipse.jgit/src/org/eclipse/jgit/treewalk/CanonicalTreeParser.java @@ -1,5 +1,5 @@ /* - * Copyright (C) 2008-2009, Google Inc. + * Copyright (C) 2008-2010, Google Inc. * Copyright (C) 2008, Shawn O. Pearce * and other copyright owners as documented in the project's IP log. * @@ -122,7 +122,9 @@ public void reset(final byte[] treeData) { raw = treeData; prevPtr = -1; currPtr = 0; - if (!eof()) + if (eof()) + nextPtr = 0; + else parseEntry(); } @@ -159,15 +161,19 @@ public CanonicalTreeParser resetRoot(final Repository repo, public CanonicalTreeParser next() { CanonicalTreeParser p = this; for (;;) { - p.next(1); - if (p.eof() && p.parent != null) { - // Parent was left pointing at the entry for us; advance - // the parent to the next entry, possibly unwinding many - // levels up the tree. - // + if (p.nextPtr == p.raw.length) { + // This parser has reached EOF, return to the parent. + if (p.parent == null) { + p.currPtr = p.nextPtr; + return p; + } p = (CanonicalTreeParser) p.parent; continue; } + + p.prevPtr = p.currPtr; + p.currPtr = p.nextPtr; + p.parseEntry(); return p; } }