LiveIntervalAnalysis: Factor out code to update liveness on vreg def removal
This cleans up code and is more in line with the general philosophy of
modifying LiveIntervals through LiveIntervalAnalysis instead of changing
them directly.
This also fixes a case where SplitEditor::removeBackCopies() would miss
the subregister ranges.
llvm-svn: 226690
diff --git a/llvm/lib/CodeGen/LiveIntervalAnalysis.cpp b/llvm/lib/CodeGen/LiveIntervalAnalysis.cpp
index 48daf2c..c03773f 100644
--- a/llvm/lib/CodeGen/LiveIntervalAnalysis.cpp
+++ b/llvm/lib/CodeGen/LiveIntervalAnalysis.cpp
@@ -1375,3 +1375,17 @@
LR->removeValNo(VNI);
}
}
+
+void LiveIntervals::removeVRegDefAt(LiveInterval &LI, SlotIndex Pos) {
+ VNInfo *VNI = LI.getVNInfoAt(Pos);
+ if (VNI == nullptr)
+ return;
+ LI.removeValNo(VNI);
+
+ // Also remove the value in subranges.
+ for (LiveInterval::SubRange &S : LI.subranges()) {
+ if (VNInfo *SVNI = S.getVNInfoAt(Pos))
+ S.removeValNo(SVNI);
+ }
+ LI.removeEmptySubRanges();
+}