Improve comment and make assert more explicit.

2 files changed, 3 insertions, 4 deletions

diff --git a/searchlib/src/vespa/searchlib/common/bitvector.cpp b/searchlib/src/vespa/searchlib/common/bitvector.cpp
index 2297e886916..4f1d3a3a72c 100644
--- a/searchlib/src/vespa/searchlib/common/bitvector.cpp
+++ b/searchlib/src/vespa/searchlib/common/bitvector.cpp
@@ -66,20 +66,18 @@ BitVector::parallellOr(vespalib::ThreadBundle & thread_bundle, vespalib::ConstAr
     size_t max_num_chunks = (size + (MIN_BITS_PER_THREAD - 1)) / MIN_BITS_PER_THREAD;
     size_t max_threads = std::max(1ul, std::min(thread_bundle.size(), max_num_chunks));
 
-    uint32_t bits_per_thread = size/max_threads;
     if (max_threads < 2) {
         for (uint32_t i(1); i < vectors.size(); i++) {
             master->orWith(*vectors[i]);
         }
     } else {
-        Index startIndex = master->getStartIndex();
         for (const BitVector *bv: vectors) {
-            assert(bv->getStartIndex() == startIndex);
+            assert(bv->getStartIndex() == 0u);
             assert(bv->size() == size);
         }
         std::vector<BitVector::OrParts> parts;
         parts.reserve(max_threads);
-        bits_per_thread = (bits_per_thread/ALIGNMENT_BITS) * ALIGNMENT_BITS;
+        uint32_t bits_per_thread = ((size/max_threads)/ALIGNMENT_BITS) * ALIGNMENT_BITS;
         Index offset = 0;
         for (uint32_t i(0); (i + 1) < max_threads; i++) {
             parts.emplace_back(vectors, offset, bits_per_thread);
diff --git a/searchlib/src/vespa/searchlib/common/bitvector.h b/searchlib/src/vespa/searchlib/common/bitvector.h
index c403ce0d8a9..30d01c4a58b 100644
--- a/searchlib/src/vespa/searchlib/common/bitvector.h
+++ b/searchlib/src/vespa/searchlib/common/bitvector.h
@@ -285,6 +285,7 @@ public:
     static void consider_enable_range_check();
     /**
      * Will slice the vectors and if possible use the thread bundle do the operation in parallell
+     * The result of the operation ends up in the first vector.
      * TODO: Extend to handle both AND/OR
      */
     static void parallellOr(vespalib::ThreadBundle & thread_bundle, vespalib::ConstArrayRef<BitVector *> vectors);