diff --git a/llvm/include/llvm/ADT/SparseBitVector.h b/llvm/include/llvm/ADT/SparseBitVector.h index a6df0acdc77f..d1e91250680d 100644 --- a/llvm/include/llvm/ADT/SparseBitVector.h +++ b/llvm/include/llvm/ADT/SparseBitVector.h @@ -334,9 +334,8 @@ class SparseBitVector { --ElementIter; } else { while (ElementIter != Elements.end() && - ElementIter->index() <= ElementIndex) + ElementIter->index() < ElementIndex) ++ElementIter; - --ElementIter; } CurrElementIter = ElementIter; return ElementIter; @@ -536,10 +535,17 @@ public: if (ElementIter == Elements.end() || ElementIter->index() != ElementIndex) { Element = new SparseBitVectorElement(ElementIndex); - // Insert does insert before, and lower bound gives the one before. - ElementIter = Elements.insert(++ElementIter, Element); + // We may have hit the beginning of our SparseBitVector, in which case, + // we may need to insert right after this element, which requires moving + // the current iterator forward one, because insert does insert before. + if (ElementIter->index() < ElementIndex) + ElementIter = Elements.insert(++ElementIter, Element); + else + ElementIter = Elements.insert(ElementIter, Element); } } + CurrElementIter = ElementIter; + ElementIter->set(Idx % ElementSize); }