diff --git a/include/llvm/CodeGen/LiveInterval.h b/include/llvm/CodeGen/LiveInterval.h index c75d5947b96..00b51a16f1e 100644 --- a/include/llvm/CodeGen/LiveInterval.h +++ b/include/llvm/CodeGen/LiveInterval.h @@ -379,6 +379,10 @@ namespace llvm { return overlapsFrom(other, other.begin()); } + /// overlaps - Return true if the live interval overlaps a range specified + /// by [Start, End). + bool overlaps(unsigned Start, unsigned End) const; + /// overlapsFrom - Return true if the intersection of the two live intervals /// is not empty. The specified iterator is a hint that we can begin /// scanning the Other interval starting at I. diff --git a/lib/CodeGen/LiveInterval.cpp b/lib/CodeGen/LiveInterval.cpp index 3f8714085ae..68d9ad4b3e6 100644 --- a/lib/CodeGen/LiveInterval.cpp +++ b/lib/CodeGen/LiveInterval.cpp @@ -123,6 +123,22 @@ bool LiveInterval::overlapsFrom(const LiveInterval& other, return false; } +/// overlaps - Return true if the live interval overlaps a range specified +/// by [Start, End). +bool LiveInterval::overlaps(unsigned Start, unsigned End) const { + assert(Start < End && "Invalid range"); + const_iterator I = begin(); + const_iterator E = end(); + const_iterator si = std::upper_bound(I, E, Start); + const_iterator ei = std::upper_bound(I, E, End); + if (si != ei) + return true; + if (si == I) + return false; + --si; + return si->contains(Start); +} + /// extendIntervalEndTo - This method is used when we want to extend the range /// specified by I to end at the specified endpoint. To do this, we should /// merge and eliminate all ranges that this will overlap with. The iterator is