Remove the Expr member from IVUsers. Instead of remembering the expression,

just ask ScalarEvolution for it on demand. This helps IVUsers be more robust
in the case of expressions changing underneath it. This fixes PR6862.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101819 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 9 insertions, 23 deletions

diff --git a/include/llvm/Analysis/IVUsers.h b/include/llvm/Analysis/IVUsers.h
index a887c83..578e6ab 100644
--- a/include/llvm/Analysis/IVUsers.h
+++ b/include/llvm/Analysis/IVUsers.h
@@ -36,9 +36,8 @@ class IVUsers;
 class IVStrideUse : public CallbackVH, public ilist_node<IVStrideUse> {
   friend class IVUsers;
 public:
-  IVStrideUse(IVUsers *P, const SCEV *E,
-              Instruction* U, Value *O)
-    : CallbackVH(U), Parent(P), Expr(E), OperandValToReplace(O) {
+  IVStrideUse(IVUsers *P, Instruction* U, Value *O)
+    : CallbackVH(U), Parent(P), OperandValToReplace(O) {
   }
 
   /// getUser - Return the user instruction for this use.
@@ -51,20 +50,6 @@ public:
     setValPtr(NewUser);
   }
 
-  /// getParent - Return a pointer to the IVUsers that owns
-  /// this IVStrideUse.
-  IVUsers *getParent() const { return Parent; }
-
-  /// getExpr - Return the expression for the use.
-  const SCEV *getExpr() const { return Expr; }
-
-  /// setExpr - Assign a new expression to this use.
-  void setExpr(const SCEV *Val) {
-    Expr = Val;
-  }
-
-  const SCEV *getStride(const Loop *L) const;
-
   /// getOperandValToReplace - Return the Value of the operand in the user
   /// instruction that this IVStrideUse is representing.
   Value *getOperandValToReplace() const {
@@ -91,9 +76,6 @@ private:
   /// Parent - a pointer to the IVUsers that owns this IVStrideUse.
   IVUsers *Parent;
 
-  /// Expr - The expression for this use.
-  const SCEV *Expr;
-
   /// OperandValToReplace - The Value of the operand in the user instruction
   /// that this IVStrideUse is representing.
   WeakVH OperandValToReplace;
@@ -161,12 +143,16 @@ public:
   /// return true.  Otherwise, return false.
   bool AddUsersIfInteresting(Instruction *I);
 
-  IVStrideUse &AddUser(const SCEV *Expr,
-                       Instruction *User, Value *Operand);
+  IVStrideUse &AddUser(Instruction *User, Value *Operand);
 
   /// getReplacementExpr - Return a SCEV expression which computes the
   /// value of the OperandValToReplace of the given IVStrideUse.
-  const SCEV *getReplacementExpr(const IVStrideUse &U) const;
+  const SCEV *getReplacementExpr(const IVStrideUse &IU) const;
+
+  /// getExpr - Return the expression for the use.
+  const SCEV *getExpr(const IVStrideUse &IU) const;
+
+  const SCEV *getStride(const IVStrideUse &IU, const Loop *L) const;
 
   typedef ilist<IVStrideUse>::iterator iterator;
   typedef ilist<IVStrideUse>::const_iterator const_iterator;