[MBP] remove an unused function parameter

[haicheng]

Summary

NFC.

[mcrosier]

LGTM.

[haicheng]

Committed in r265596.

lib/CodeGen/MachineBlockPlacement.cpp

class MachineBlockPlacement : public MachineFunctionPass {
   void markChainSuccessors(BlockChain &Chain, MachineBasicBlock *LoopHeaderBB,
                            SmallVectorImpl<MachineBasicBlock *> &BlockWorkList,
                            const BlockFilterSet *BlockFilter = nullptr);
   MachineBasicBlock *selectBestSuccessor(MachineBasicBlock *BB,
                                          BlockChain &Chain,
                                          const BlockFilterSet *BlockFilter);
   MachineBasicBlock *
   selectBestCandidateBlock(BlockChain &Chain,
-                           SmallVectorImpl<MachineBasicBlock *> &WorkList,
-                           const BlockFilterSet *BlockFilter);
+                           SmallVectorImpl<MachineBasicBlock *> &WorkList);
   MachineBasicBlock *
   getFirstUnplacedBlock(MachineFunction &F, const BlockChain &PlacedChain,
                         MachineFunction::iterator &PrevUnplacedBlockIt,
                         const BlockFilterSet *BlockFilter);
 
   /// \brief Add a basic block to the work list if it is apropriate.
   ///
   /// If the optional parameter BlockFilter is provided, only MBB

 /// blocks and select the most profitable one to place. The definition of
 /// profitable only really makes sense in the context of a loop. This returns
 /// the most frequently visited block in the worklist, which in the case of
 /// a loop, is the one most desirable to be physically close to the rest of the
 /// loop body in order to improve icache behavior.
 ///
 /// \returns The best block found, or null if none are viable.
 MachineBasicBlock *MachineBlockPlacement::selectBestCandidateBlock(
-    BlockChain &Chain, SmallVectorImpl<MachineBasicBlock *> &WorkList,
-    const BlockFilterSet *BlockFilter) {
+    BlockChain &Chain, SmallVectorImpl<MachineBasicBlock *> &WorkList) {
   // Once we need to walk the worklist looking for a candidate, cleanup the
   // worklist of already placed entries.
   // FIXME: If this shows up on profiles, it could be folded (at the cost of
   // some code complexity) into the loop below.
   WorkList.erase(std::remove_if(WorkList.begin(), WorkList.end(),
                                 [&](MachineBasicBlock *BB) {
                                   return BlockToChain.lookup(BB) == &Chain;
                                 }),
for (;;) {
     // Look for the best viable successor if there is one to place immediately
     // after this block.
     MachineBasicBlock *BestSucc = selectBestSuccessor(BB, Chain, BlockFilter);
 
     // If an immediate successor isn't available, look for the best viable
     // block among those we've identified as not violating the loop's CFG at
     // this point. This won't be a fallthrough, but it will increase locality.
     if (!BestSucc)
-      BestSucc = selectBestCandidateBlock(Chain, BlockWorkList, BlockFilter);
+      BestSucc = selectBestCandidateBlock(Chain, BlockWorkList);
 
     if (!BestSucc) {
       BestSucc =
           getFirstUnplacedBlock(F, Chain, PrevUnplacedBlockIt, BlockFilter);
       if (!BestSucc)
         break;
 
       DEBUG(dbgs() << "Unnatural loop CFG detected, forcibly merging the "