Fix the warning caused by unused parameter

Author: Mel-Chen

llvm/include/llvm/Analysis/IVDescriptors.h

@@ -166,8 +166,8 @@ class RecurrenceDescriptor {
   /// other is a PHI value.
   // TODO: FindLast does not need be restricted to increasing loop induction
   // variables.
-  static InstDesc isFindLastIVPattern(Loop *Loop, PHINode *OrigPhi,
-                                      Instruction *I, ScalarEvolution *SE);
+  static InstDesc isFindLastIVPattern(PHINode *OrigPhi, Instruction *I,
+                                      ScalarEvolution *SE);
 
   /// Returns a struct describing if the instruction is a
   /// Select(FCmp(X, Y), (Z = X op PHINode), PHINode) instruction pattern.

llvm/lib/Analysis/IVDescriptors.cpp

@@ -690,8 +690,8 @@ RecurrenceDescriptor::isAnyOfPattern(Loop *Loop, PHINode *OrigPhi,
 // value of the data type or a non-constant value by using mask and multiple
 // reduction operations.
 RecurrenceDescriptor::InstDesc
-RecurrenceDescriptor::isFindLastIVPattern(Loop *Loop, PHINode *OrigPhi,
-                                          Instruction *I, ScalarEvolution *SE) {
+RecurrenceDescriptor::isFindLastIVPattern(PHINode *OrigPhi, Instruction *I,
+                                          ScalarEvolution *SE) {
   // Only match select with single use cmp condition.
   // TODO: Only handle single use for now.
   CmpInst::Predicate Pred;
@@ -888,7 +888,7 @@ RecurrenceDescriptor::InstDesc RecurrenceDescriptor::isRecurrenceInstr(
         Kind == RecurKind::Add || Kind == RecurKind::Mul)
       return isConditionalRdxPattern(Kind, I);
     if (isFindLastIVRecurrenceKind(Kind))
-      return isFindLastIVPattern(L, OrigPhi, I, SE);
+      return isFindLastIVPattern(OrigPhi, I, SE);
     [[fallthrough]];
   case Instruction::FCmp:
   case Instruction::ICmp: