1 files changed, 16 insertions, 0 deletions
diff --git a/lib/CodeGen/LiveInterval.cpp b/lib/CodeGen/LiveInterval.cpp
index c2dbd6ab75..a37296f77b 100644
--- a/lib/CodeGen/LiveInterval.cpp
+++ b/lib/CodeGen/LiveInterval.cpp
@@ -291,6 +291,22 @@ LiveInterval::addRangeFrom(LiveRange LR, iterator From) {
   return ranges.insert(it, LR);
 }
 
+/// extendInBlock - If this interval is live before UseIdx in the basic
+/// block that starts at StartIdx, extend it to be live at UseIdx and return
+/// the value. If there is no live range before UseIdx, return NULL.
+VNInfo *LiveInterval::extendInBlock(SlotIndex StartIdx, SlotIndex UseIdx) {
+  if (empty())
+    return 0;
+  iterator I = std::upper_bound(begin(), end(), UseIdx);
+  if (I == begin())
+    return 0;
+  --I;
+  if (I->end <= StartIdx)
+    return 0;
+  if (I->end <= UseIdx)
+    extendIntervalEndTo(I, UseIdx.getNextSlot());
+  return I->valno;
+}
 
 /// removeRange - Remove the specified range from this interval.  Note that
 /// the range must be in a single LiveRange in its entirety.