From e064487ca28c12ba774c2f43a3c7acbdb1a278c9 Mon Sep 17 00:00:00 2001
From: brunoerg <brunoely.gc@gmail.com>
Date: Thu, 23 Mar 2023 15:45:56 -0300
Subject: [PATCH] addrman, refactor: improve stochastic test in `AddSingle`

This commit changes this algo to be O(1) instead of O(n) by using `<<`.
---
 src/addrman.cpp | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/src/addrman.cpp b/src/addrman.cpp
index 212baab9d45..5d532bedf9c 100644
--- a/src/addrman.cpp
+++ b/src/addrman.cpp
@@ -585,11 +585,10 @@ bool AddrManImpl::AddSingle(const CAddress& addr, const CNetAddr& source, std::c
             return false;
 
         // stochastic test: previous nRefCount == N: 2^N times harder to increase it
-        int nFactor = 1;
-        for (int n = 0; n < pinfo->nRefCount; n++)
-            nFactor *= 2;
-        if (nFactor > 1 && (insecure_rand.randrange(nFactor) != 0))
-            return false;
+        if (pinfo->nRefCount > 0) {
+            const int nFactor{1 << pinfo->nRefCount};
+            if (insecure_rand.randrange(nFactor) != 0) return false;
+        }
     } else {
         pinfo = Create(addr, source, &nId);
         pinfo->nTime = std::max(NodeSeconds{0s}, pinfo->nTime - time_penalty);