From c9b35241e1e67e0122be109a3e59e56ed3f9907c Mon Sep 17 00:00:00 2001
From: Andrew Noyes <andrew@weaselab.dev>
Date: Wed, 14 Feb 2024 12:05:33 -0800
Subject: [PATCH] Factor out "maxRightOf"

---
 ConflictSet.cpp | 17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/ConflictSet.cpp b/ConflictSet.cpp
index 5af9107..5f29b5d 100644
--- a/ConflictSet.cpp
+++ b/ConflictSet.cpp
@@ -919,6 +919,16 @@ descend(int &depth, int &lcp, Node *newNode, std::span<const uint8_t> end,
                     newNode->partialKey + newNode->partialKeyLen);
 }
 
+// Precondition: node has a child at index begin
+int64_t maxRightOf(Node *n, int begin) {
+  int64_t result = std::numeric_limits<int64_t>::lowest();
+  while (begin >= 0) {
+    result = std::max(result, getChildExists(n, begin)->maxVersion);
+    begin = getChildGeq(n, begin + 1);
+  }
+  return result;
+}
+
 bool checkRangeRead(Node *n, const std::span<const uint8_t> begin,
                     const std::span<const uint8_t> end, int64_t readVersion,
                     Arena &arena) {
@@ -1039,11 +1049,8 @@ bool checkRangeRead(Node *n, const std::span<const uint8_t> begin,
             fprintf(stderr, "%s, right of %02x\n",
                     printable(searchPath).c_str(), next);
 #endif
-            while (next >= 0) {
-              if (getChildExists(iter, next)->maxVersion > readVersion) {
-                return false;
-              }
-              next = getChildGeq(iter, next + 1);
+            if (maxRightOf(iter, next) > readVersion) {
+              return false;
             }
           } else {
             iter = getChildExists(iter, next);