Subzero: Improve usability of liveness-related tools.

src/IceRegAlloc.h

Index: src/IceRegAlloc.h
diff --git a/src/IceRegAlloc.h b/src/IceRegAlloc.h
index 7742ad77a7712c9117568f5722b6e908e6c233b8..6508aa514498b1e70c11cfc2da9021583078915a 100644
--- a/src/IceRegAlloc.h
+++ b/src/IceRegAlloc.h
@@ -41,6 +41,7 @@ public:
 private:
   using OrderedRanges = CfgVector<Variable *>;
   using UnorderedRanges = CfgVector<Variable *>;
+  using DefUseErrorList = llvm::SmallVector<SizeT, 10>;
 
   class IterationState {
     IterationState(const IterationState &) = delete;
@@ -58,6 +59,10 @@ private:
     llvm::SmallVector<RegWeight, REGS_SIZE> Weights;
   };
 
+  bool livenessValidateIntervals(const DefUseErrorList &DefsWithoutUses,
+                                 const DefUseErrorList &UsesBeforeDefs,
+                                 const CfgVector<InstNumberT> &LRBegin,
+                                 const CfgVector<InstNumberT> &LREnd);
   void initForGlobal();
   void initForInfOnly();
   /// Move an item from the From set to the To set. From[Index] is pushed onto