From: Mikko Rasa <tdb@tdb.fi>
Date: Sat, 3 Apr 2021 15:44:36 +0000 (+0300)
Subject: Add folding functions for hashes
X-Git-Url: http://git.tdb.fi/?a=commitdiff_plain;h=229f0438383b1ab7d0de0f9ea9a9a2912363bdbc;p=libs%2Fcore.git

Add folding functions for hashes
---

diff --git a/source/core/hash.h b/source/core/hash.h
index 75aba09..d696cae 100644
--- a/source/core/hash.h
+++ b/source/core/hash.h
@@ -31,6 +31,12 @@ Convenience function to compute a 64-bit hash of a string.
 inline UInt64 hash64(const std::string &s, unsigned b = 64)
 { return hash64(s.data(), s.size(), b); }
 
+inline UInt32 fold32(UInt64 hash)
+{ return hash^(hash>>32); }
+
+inline UInt16 fold16(UInt64 hash)
+{ return hash^(hash>>16)^(hash>>32)^(hash>>48); }
+
 } // namespace Msp
 
 #endif