Transfer simply defined values directly without recomputing liveness and SSA.

Values that map to a single new value in a new interval after splitting don't
need new PHIDefs, and if the parent value was never rematerialized the live
range will be the same.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126894 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/LiveRangeEdit.h b/lib/CodeGen/LiveRangeEdit.h
index 73f69ed..d5795cd 100644
--- a/lib/CodeGen/LiveRangeEdit.h
+++ b/lib/CodeGen/LiveRangeEdit.h
@@ -41,11 +41,11 @@
 
   /// remattable_ - Values defined by remattable instructions as identified by
   /// tii.isTriviallyReMaterializable().
-  SmallPtrSet<VNInfo*,4> remattable_;
+  SmallPtrSet<const VNInfo*,4> remattable_;
 
   /// rematted_ - Values that were actually rematted, and so need to have their
   /// live range trimmed or entirely removed.
-  SmallPtrSet<VNInfo*,4> rematted_;
+  SmallPtrSet<const VNInfo*,4> rematted_;
 
   /// scanRemattable - Identify the parent_ values that may rematerialize.
   void scanRemattable(LiveIntervals &lis,
@@ -120,12 +120,12 @@
 
   /// markRematerialized - explicitly mark a value as rematerialized after doing
   /// it manually.
-  void markRematerialized(VNInfo *ParentVNI) {
+  void markRematerialized(const VNInfo *ParentVNI) {
     rematted_.insert(ParentVNI);
   }
 
   /// didRematerialize - Return true if ParentVNI was rematerialized anywhere.
-  bool didRematerialize(VNInfo *ParentVNI) const {
+  bool didRematerialize(const VNInfo *ParentVNI) const {
     return rematted_.count(ParentVNI);
   }
 };