Add missing newlines at EOF (for clang++).

[oota-llvm.git] / lib / Transforms / Utils / SimplifyCFG.cpp

diff --git a/lib/Transforms/Utils/SimplifyCFG.cpp b/lib/Transforms/Utils/SimplifyCFG.cpp
index 8dbc8081c5a40cf3058fc8982fad8482c3fa805a..d7ca45e6e9700eafa253fbb12d32bc6b2f8e55e9 100644 (file)
--- a/lib/Transforms/Utils/SimplifyCFG.cpp
+++ b/lib/Transforms/Utils/SimplifyCFG.cpp
@@ -1589,69 +1589,6 @@ static bool SimplifyCondBranchToCondBranch(BranchInst *PBI, BranchInst *BI) {
   return true;
 }
 
-/// EliminateDuplicatePHINodes - Check for and eliminate duplicate PHI
-/// nodes in this block. This doesn't try to be clever about PHI nodes
-/// which differ only in the order of the incoming values, but instcombine
-/// orders them so it usually won't matter.
-///
-static bool EliminateDuplicatePHINodes(BasicBlock *BB) {
-  bool Changed = false;
-  
-  // This implementation doesn't currently consider undef operands
-  // specially. Theroetically, two phis which are identical except for
-  // one having an undef where the other doesn't could be collapsed.
-
-  // Map from PHI hash values to PHI nodes. If multiple PHIs have
-  // the same hash value, the element is the first PHI in the
-  // linked list in CollisionMap.
-  DenseMap<uintptr_t, PHINode *> HashMap;
-
-  // Maintain linked lists of PHI nodes with common hash values.
-  DenseMap<PHINode *, PHINode *> CollisionMap;
-
-  // Examine each PHI.
-  for (BasicBlock::iterator I = BB->begin();
-       PHINode *PN = dyn_cast<PHINode>(I++); ) {
-    // Compute a hash value on the operands. Instcombine will likely have sorted
-    // them, which helps expose duplicates, but we have to check all the
-    // operands to be safe in case instcombine hasn't run.
-    uintptr_t Hash = 0;
-    for (User::op_iterator I = PN->op_begin(), E = PN->op_end(); I != E; ++I) {
-      // This hash algorithm is quite weak as hash functions go, but it seems
-      // to do a good enough job for this particular purpose, and is very quick.
-      Hash ^= reinterpret_cast<uintptr_t>(static_cast<Value *>(*I));
-      Hash = (Hash << 7) | (Hash >> (sizeof(uintptr_t) * CHAR_BIT - 7));
-    }
-    // If we've never seen this hash value before, it's a unique PHI.
-    std::pair<DenseMap<uintptr_t, PHINode *>::iterator, bool> Pair =
-      HashMap.insert(std::make_pair(Hash, PN));
-    if (Pair.second) continue;
-    // Otherwise it's either a duplicate or a hash collision.
-    for (PHINode *OtherPN = Pair.first->second; ; ) {
-      if (OtherPN->isIdenticalTo(PN)) {
-        // A duplicate. Replace this PHI with its duplicate.
-        PN->replaceAllUsesWith(OtherPN);
-        PN->eraseFromParent();
-        Changed = true;
-        break;
-      }
-      // A non-duplicate hash collision.
-      DenseMap<PHINode *, PHINode *>::iterator I = CollisionMap.find(OtherPN);
-      if (I == CollisionMap.end()) {
-        // Set this PHI to be the head of the linked list of colliding PHIs.
-        PHINode *Old = Pair.first->second;
-        Pair.first->second = PN;
-        CollisionMap[PN] = Old;
-        break;
-      }
-      // Procede to the next PHI in the list.
-      OtherPN = I->second;
-    }
-  }
-
-  return Changed;
-}
-
 /// SimplifyCFG - This function is used to do simplification of a CFG.  For
 /// example, it adjusts branches to branches to eliminate the extra hop, it
 /// eliminates unreachable basic blocks, and does other "peephole" optimization