Minimize the slot indexes spanned by register ranges created when splitting.

When an interfering live range ends at a dead slot index between two
instructions, make sure that the inserted copy instruction gets a slot index
after the dead ones. This makes it possible to avoid the interference.

Ideally, there shouldn't be interference ending at a deleted instruction, but
physical register coalescing can sometimes do that to sub-registers.

This fixes PR9823.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130687 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/LiveRangeEdit.h b/lib/CodeGen/LiveRangeEdit.h
index c008d76..14d227e 100644
--- a/lib/CodeGen/LiveRangeEdit.h
+++ b/lib/CodeGen/LiveRangeEdit.h
@@ -165,7 +165,8 @@
                             const Remat &RM,
                             LiveIntervals&,
                             const TargetInstrInfo&,
-                            const TargetRegisterInfo&);
+                            const TargetRegisterInfo&,
+                            bool Late = false);
 
   /// markRematerialized - explicitly mark a value as rematerialized after doing
   /// it manually.