!fixup add message, refactor constructor

Author: fhahn

llvm/include/llvm/Analysis/IVDescriptors.h

@@ -93,14 +93,15 @@ class RecurrenceDescriptor {
 
   RecurrenceDescriptor(Value *Start, Instruction *Exit, StoreInst *Store,
                        RecurKind K, FastMathFlags FMF, Instruction *ExactFP,
-                       Type *RT, bool Signed, bool Ordered,
-                       SmallPtrSetImpl<Instruction *> &CI,
-                       unsigned MinWidthCastToRecurTy)
+                       Type *RT, bool Signed = false, bool Ordered = false,
+                       const SmallPtrSetImpl<Instruction *> *CI = nullptr,
+                       unsigned MinWidthCastToRecurTy = -1U)
       : IntermediateStore(Store), StartValue(Start), LoopExitInstr(Exit),
         Kind(K), FMF(FMF), ExactFPMathInst(ExactFP), RecurrenceType(RT),
         IsSigned(Signed), IsOrdered(Ordered),
         MinWidthCastToRecurrenceType(MinWidthCastToRecurTy) {
-    CastInsts.insert_range(CI);
+    if (CI)
+      CastInsts.insert_range(*CI);
   }
 
   /// This POD struct holds information about a potential recurrence operation.

llvm/lib/Analysis/IVDescriptors.cpp

@@ -389,7 +389,7 @@ static RecurrenceDescriptor getMinMaxRecurrence(PHINode *Phi, Loop *TheLoop,
   return RecurrenceDescriptor(
       Phi->getIncomingValueForBlock(TheLoop->getLoopPreheader()),
       cast<Instruction>(RdxNext), IntermediateStore, RK, FMF, nullptr,
-      Phi->getType(), false, false, Casts, -1U);
+      Phi->getType());
 }
 
 bool RecurrenceDescriptor::AddReductionVar(
@@ -753,7 +753,7 @@ bool RecurrenceDescriptor::AddReductionVar(
   // Save the description of this reduction variable.
   RecurrenceDescriptor RD(RdxStart, ExitInstruction, IntermediateStore, Kind,
                           FMF, ExactFPMathInst, RecurrenceType, IsSigned,
-                          IsOrdered, CastInsts, MinWidthCastToRecurrenceType);
+                          IsOrdered, &CastInsts, MinWidthCastToRecurrenceType);
   RedDes = RD;
 
   return true;
@@ -1105,7 +1105,7 @@ bool RecurrenceDescriptor::isReductionPHI(PHINode *Phi, Loop *TheLoop,
   if (RD.getRecurrenceKind() != RecurKind::None) {
     assert(
         RecurrenceDescriptor::isMinMaxRecurrenceKind(RD.getRecurrenceKind()) &&
-        "must return a min/max recurrence kind");
+        "Expected a min/max recurrence kind");
     LLVM_DEBUG(dbgs() << "Found a min/max reduction PHI." << *Phi << "\n");
     RedDes = RD;
     return true;