Add a new getPredicateOnEdge method which returns more rich information for

constant constraints.  Improve the LVI lattice to include inequality 
constraints.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86950 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 8 insertions, 6 deletions

diff --git a/include/llvm/Analysis/LazyValueInfo.h b/include/llvm/Analysis/LazyValueInfo.h
index d346696..dd80fce 100644
--- a/include/llvm/Analysis/LazyValueInfo.h
+++ b/include/llvm/Analysis/LazyValueInfo.h
@@ -31,19 +31,21 @@ public:
   static char ID;
   LazyValueInfo() : FunctionPass(&ID), PImpl(0) {}
 
-  /// Tristate - This is used to return yes/no/dunno results.
+  /// Tristate - This is used to return true/false/dunno results.
   enum Tristate {
-    Unknown = -1, No = 0, Yes = 1
+    Unknown = -1, False = 0, True = 1
   };
   
   
   // Public query interface.
   
+  /// getPredicateOnEdge - Determine whether the specified value comparison
+  /// with a constant is known to be true or false on the specified CFG edge.
+  /// Pred is a CmpInst predicate.
+  Tristate getPredicateOnEdge(unsigned Pred, Value *V, Constant *C,
+                              BasicBlock *FromBB, BasicBlock *ToBB);
+  
   
-  /// isEqual - Determine whether the specified value is known to be equal or
-  /// not-equal to the specified constant at the end of the specified block.
-  Tristate isEqual(Value *V, Constant *C, BasicBlock *BB);
-
   /// getConstant - Determine whether the specified value is known to be a
   /// constant at the end of the specified block.  Return null if not.
   Constant *getConstant(Value *V, BasicBlock *BB);