From a8daf34a080f04d356fbd236e08a4af08b997ed1 Mon Sep 17 00:00:00 2001
From: JoelKatz <DavidJoelSchwartz@GMail.com>
Date: Wed, 6 Mar 2013 01:10:23 -0800
Subject: [PATCH] Compute SHAMapNode hashes faster.

---
 src/cpp/ripple/SHAMap.cpp | 9 ++-------
 1 file changed, 2 insertions(+), 7 deletions(-)

diff --git a/src/cpp/ripple/SHAMap.cpp b/src/cpp/ripple/SHAMap.cpp
index 651963806..6bc488ae0 100644
--- a/src/cpp/ripple/SHAMap.cpp
+++ b/src/cpp/ripple/SHAMap.cpp
@@ -23,16 +23,11 @@ DECLARE_INSTANCE(SHAMapTreeNode);
 
 void SHAMapNode::setHash() const
 {
-#if 0
-	std::size_t h = theApp->getNonceST() + (mDepth * 0x9e3779b9);
-	mHash = mNodeID.hash_combine(h);
-#else
 	std::size_t h = theApp->getNonceST() + (mDepth * 0x9e3779b9);
 	const unsigned int *ptr = reinterpret_cast<const unsigned int *>(mNodeID.begin());
-	for (int i = (mDepth + 3) / 4; i != 0; --i)
-		boost::hash_combine(h, *ptr++);
+	for (int i = (mDepth + 7) / 8; i != 0; --i)
+		h = (h * 0x9e3779b9) ^ *ptr++;
 	mHash = h;
-#endif
 }
 
 std::size_t hash_value(const SHAMapNode& mn)