Early return if common prefix isn't a prefix of an entry

For range reads

ConflictSet.cpp

@@ -2785,6 +2785,8 @@ bool checkRangeRead(Node *n, std::span<const uint8_t> begin,
 
   auto remaining = begin.subspan(0, lcp);
   Arena arena;
+  // If the common prefix isn't a prefix of any physical entry in the tree, we
+  // can go to "downLeftSpine"
   for (;; ++tls->range_read_iterations_accum) {
     assert(getSearchPath(arena, n) <=>
                begin.subspan(0, lcp - remaining.size()) ==
@@ -2794,12 +2796,38 @@ bool checkRangeRead(Node *n, std::span<const uint8_t> begin,
     }
     auto [child, v] = getChildAndMaxVersion(n, remaining[0]);
     if (child == nullptr) {
-      break;
+      auto c = getChildGeq(n, remaining[0]);
+      if (c != nullptr) {
+        n = c;
+        goto downLeftSpine;
+      } else {
+        n = nextSibling(n);
+        if (n == nullptr) {
+          return true;
         }
+        goto downLeftSpine;
+      }
+    }
+
     if (child->partialKeyLen > 0) {
       int cl = std::min<int>(child->partialKeyLen, remaining.size() - 1);
       int i =
           longestCommonPrefix(child->partialKey(), remaining.data() + 1, cl);
+      if (i < cl) {
+        auto c = child->partialKey()[i] <=> remaining[1 + i];
+        if (c > 0) {
+          n = child;
+          goto downLeftSpine;
+        } else {
+          n = nextSibling(child);
+          if (n == nullptr) {
+            return true;
+          }
+          goto downLeftSpine;
+        }
+      }
+      // If the partial key is longer than the common prefix (remaining), we
+      // still need to keep searching
       if (i != child->partialKeyLen) {
         break;
       }
@@ -2815,6 +2843,12 @@ bool checkRangeRead(Node *n, std::span<const uint8_t> begin,
   }
   assert(getSearchPath(arena, n) <=> begin.subspan(0, lcp - remaining.size()) ==
          0);
+  if (0) {
+  downLeftSpine:
+    for (; !n->entryPresent; n = getFirstChildExists(n)) {
+    }
+    return n->entry.rangeVersion <= readVersion;
+  }
 
   const int consumed = lcp - remaining.size();
   assume(consumed >= 0);