Make the code that updates ScalarEvolution's internal state in response

to a loop deletion more thorough. Don't prune the def-use tree search at
instructions that don't have SCEVs computed, because an instruction with
a user that has a computed SCEV may itself lack a computed SCEV.  Also,
remove loop-related values from the ValuesAtScopes and
ConstantEvolutionLoopExitValues maps as well.

This fixes a regression in 483.xalancbmk.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75030 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/Analysis/ScalarEvolution.h

@@ -346,11 +346,6 @@ namespace llvm {
     Constant *getConstantEvolutionLoopExitValue(PHINode *PN, const APInt& BEs,
                                                 const Loop *L);
 
-    /// forgetLoopPHIs - Delete the memoized SCEVs associated with the
-    /// PHI nodes in the given loop. This is used when the trip count of
-    /// the loop may have changed.
-    void forgetLoopPHIs(const Loop *L);
-
   public:
     static char ID; // Pass identification, replacement for typeid
     ScalarEvolution();