From a74962bc3c60691843bc913e354c1bdaea50e59d Mon Sep 17 00:00:00 2001
From: Peter Dimov <pdimov@gmail.com>
Date: Mon, 30 Jan 2023 20:03:01 +0200
Subject: [PATCH] Revert reversion of 32 bit mulx multiplier

---
 include/boost/unordered/detail/mulx.hpp | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/include/boost/unordered/detail/mulx.hpp b/include/boost/unordered/detail/mulx.hpp
index aa50f72a..c2ec2701 100644
--- a/include/boost/unordered/detail/mulx.hpp
+++ b/include/boost/unordered/detail/mulx.hpp
@@ -107,11 +107,13 @@ inline std::size_t mulx( std::size_t x ) noexcept
 {
 #if defined(BOOST_UNORDERED_64B_ARCHITECTURE)
 
+    // multiplier is phi
     return (std::size_t)mulx64( (boost::uint64_t)x, 0x9E3779B97F4A7C15ull );
 
 #else /* 32 bits assumed */
 
-    return mulx32( x, 0x9E3779B9u );
+    // multiplier from https://arxiv.org/abs/2001.05304
+    return mulx32( x, 0xE817FB2Du );
 
 #endif
 }