[SCEV] Remove unused getOrInsertCanonicalInductionVariable (NFC)

The last use was removed on Mar 22, 2012 in commit
f47d0af551.

llvm/include/llvm/Transforms/Utils/ScalarEvolutionExpander.h

@@ -247,12 +247,6 @@ public:
     return false;
   }
 
-  /// This method returns the canonical induction variable of the specified
-  /// type for the specified loop (inserting one if there is none).  A
-  /// canonical induction variable starts at zero and steps by one on each
-  /// iteration.
-  PHINode *getOrInsertCanonicalInductionVariable(const Loop *L, Type *Ty);
-
   /// Return the induction variable increment's IV operand.
   Instruction *getIVIncOperand(Instruction *IncV, Instruction *InsertPos,
                                bool allowScale);

llvm/lib/Transforms/Utils/ScalarEvolutionExpander.cpp

@@ -1986,28 +1986,6 @@ void SCEVExpander::rememberInstruction(Value *I) {
   }
 }
 
-/// getOrInsertCanonicalInductionVariable - This method returns the
-/// canonical induction variable of the specified type for the specified
-/// loop (inserting one if there is none).  A canonical induction variable
-/// starts at zero and steps by one on each iteration.
-PHINode *
-SCEVExpander::getOrInsertCanonicalInductionVariable(const Loop *L,
-                                                    Type *Ty) {
-  assert(Ty->isIntegerTy() && "Can only insert integer induction variables!");
-
-  // Build a SCEV for {0,+,1}<L>.
-  // Conservatively use FlagAnyWrap for now.
-  const SCEV *H = SE.getAddRecExpr(SE.getConstant(Ty, 0),
-                                   SE.getConstant(Ty, 1), L, SCEV::FlagAnyWrap);
-
-  // Emit code for it.
-  SCEVInsertPointGuard Guard(Builder, this);
-  PHINode *V = cast<PHINode>(expandCodeForImpl(
-      H, nullptr, &*L->getHeader()->getFirstInsertionPt(), false));
-
-  return V;
-}
-
 /// replaceCongruentIVs - Check for congruent phis in this loop header and
 /// replace them with their most canonical representative. Return the number of
 /// phis eliminated.