Simplify and fix bugs

ConflictSet.cpp

@@ -27,7 +27,7 @@ int compare(std::span<const uint8_t> lhs, std::span<const uint8_t> rhs) {
   if (c != 0) {
     return c;
   }
-  return int(rhs.size()) - int(lhs.size());
+  return int(lhs.size()) - int(rhs.size());
 }
 
 std::span<uint8_t> strincMutate(std::span<uint8_t> str, bool &ok) {
@@ -774,74 +774,50 @@ bool checkRangeRead(Node *n, const std::span<const uint8_t> begin,
                     const std::span<const uint8_t> end, int64_t readVersion,
                     Arena &arena) {
   auto left = FirstGeqStepwise{n, begin};
-  auto right = FirstGeqStepwise{n, end};
-  bool leftDone = left.step();
-  bool rightDone = right.step();
-  if (!leftDone && !rightDone) {
-    for (;;) {
-      if (left.phase == FirstGeqStepwise::Search &&
-          right.phase == FirstGeqStepwise::Search &&
-          left.n->maxVersion <= readVersion) {
-        return true;
-      }
-      leftDone = left.step();
-      rightDone = right.step();
-      if (leftDone || rightDone) {
-        break;
-      }
-      if (left.n != right.n) {
-        break;
-      }
-    }
-  }
-
-  if (!leftDone) {
-    while (!left.step())
-      ;
-  }
-
-  if (!rightDone) {
-    while (!right.step())
-      ;
-  }
+  while (!left.step())
+    ;
 
 #if DEBUG_VERBOSE && !defined(NDEBUG)
   fprintf(stderr, "firstGeq for `%s' got `%s'\n", printable(begin).c_str(),
           getSearchPathPrintable(left.n).c_str());
-  fprintf(stderr, "firstGeq for `%s' got `%s'\n", printable(end).c_str(),
-          getSearchPathPrintable(right.n).c_str());
 #endif
 
-  if (left.n != nullptr && left.cmp != 0 &&
-      left.n->entry.rangeVersion > readVersion) {
-    return false;
-  }
-  if (left.n == right.n) {
+  if (left.n == nullptr) {
     return true;
   }
-  assert(left.n != nullptr);
-  if (left.n->entry.pointVersion > readVersion) {
-    return false;
-  }
 
   auto searchPath = getSearchPath(arena, left.n);
 
-  for (auto *iter = nextPhysical(left.n, searchPath); iter != right.n;) {
-    assert(searchPath == getSearchPath(arena, iter));
-    if (iter->entryPresent && iter->entry.rangeVersion > readVersion) {
-      return false;
+  if (left.cmp != 0 && left.n->entry.rangeVersion > readVersion) {
+    return false;
+  }
+
+  bool first = true;
+  for (auto *iter = left.n; iter != nullptr && compare(searchPath, end) < 0;
+       first = false) {
+    if (iter->entryPresent) {
+      if (!first && iter->entry.rangeVersion > readVersion) {
+        return false;
+      }
+      if (iter->entry.pointVersion > readVersion) {
+        return false;
+      }
     }
-    bool ok = true;
+
+    assert(searchPath == getSearchPath(arena, iter));
 #if DEBUG_VERBOSE && !defined(NDEBUG)
     fprintf(stderr, "Max version of keys starting with %s: %" PRId64 "\n",
             printable(searchPath).c_str(), iter->maxVersion);
 #endif
+    bool ok = true;
     auto rangeEnd = strincMutate(searchPath, ok);
+    int c;
     if (!ok) {
-      return iter->maxVersion <= readVersion;
+      goto iterate;
     }
-    int c = compare(rangeEnd, end);
+    c = compare(rangeEnd, end);
     --rangeEnd.back();
+
     if (c == 0) {
       return iter->maxVersion <= readVersion;
     } else if (c < 0) {
@@ -850,6 +826,7 @@ bool checkRangeRead(Node *n, const std::span<const uint8_t> begin,
       }
       iter = nextSibling(iter, searchPath);
     } else {
+    iterate:
       if (iter->maxVersion <= readVersion) {
         return true;
       }