1 files changed, 0 insertions, 205 deletions
diff --git a/lib/Transforms/Scalar/GCSE.cpp b/lib/Transforms/Scalar/GCSE.cpp
deleted file mode 100644
index 9d3f1a8750..0000000000
--- a/lib/Transforms/Scalar/GCSE.cpp
+++ /dev/null
@@ -1,205 +0,0 @@
-//===-- GCSE.cpp - SSA-based Global Common Subexpression Elimination ------===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// This pass is designed to be a very quick global transformation that
-// eliminates global common subexpressions from a function.  It does this by
-// using an existing value numbering analysis pass to identify the common
-// subexpressions, eliminating them when possible.
-//
-// This pass is deprecated by the Global Value Numbering pass (which does a
-// better job with its own value numbering).
-//
-//===----------------------------------------------------------------------===//
-
-#define DEBUG_TYPE "gcse"
-#include "llvm/Transforms/Scalar.h"
-#include "llvm/Instructions.h"
-#include "llvm/Function.h"
-#include "llvm/Type.h"
-#include "llvm/Analysis/ConstantFolding.h"
-#include "llvm/Analysis/Dominators.h"
-#include "llvm/Analysis/ValueNumbering.h"
-#include "llvm/ADT/DepthFirstIterator.h"
-#include "llvm/ADT/Statistic.h"
-#include "llvm/Support/Compiler.h"
-#include <algorithm>
-using namespace llvm;
-
-STATISTIC(NumInstRemoved, "Number of instructions removed");
-STATISTIC(NumLoadRemoved, "Number of loads removed");
-STATISTIC(NumCallRemoved, "Number of calls removed");
-STATISTIC(NumNonInsts   , "Number of instructions removed due "
-                          "to non-instruction values");
-STATISTIC(NumArgsRepl   , "Number of function arguments replaced "
-                          "with constant values");
-namespace {
-  struct VISIBILITY_HIDDEN GCSE : public FunctionPass {
-    static char ID; // Pass identification, replacement for typeid
-    GCSE() : FunctionPass((intptr_t)&ID) {}
-
-    virtual bool runOnFunction(Function &F);
-
-  private:
-    void ReplaceInstructionWith(Instruction *I, Value *V);
-
-    // This transformation requires dominator and immediate dominator info
-    virtual void getAnalysisUsage(AnalysisUsage &AU) const {
-      AU.setPreservesCFG();
-      AU.addRequired<DominatorTree>();
-      AU.addRequired<ValueNumbering>();
-    }
-  };
-}
-
-char GCSE::ID = 0;
-static RegisterPass<GCSE>
-X("gcse", "Global Common Subexpression Elimination");
-
-// createGCSEPass - The public interface to this file...
-FunctionPass *llvm::createGCSEPass() { return new GCSE(); }
-
-// GCSE::runOnFunction - This is the main transformation entry point for a
-// function.
-//
-bool GCSE::runOnFunction(Function &F) {
-  bool Changed = false;
-
-  // Get pointers to the analysis results that we will be using...
-  DominatorTree &DT = getAnalysis<DominatorTree>();
-  ValueNumbering &VN = getAnalysis<ValueNumbering>();
-
-  std::vector<Value*> EqualValues;
-
-  // Check for value numbers of arguments.  If the value numbering
-  // implementation can prove that an incoming argument is a constant or global
-  // value address, substitute it, making the argument dead.
-  for (Function::arg_iterator AI = F.arg_begin(), E = F.arg_end(); AI != E;++AI)
-    if (!AI->use_empty()) {
-      VN.getEqualNumberNodes(AI, EqualValues);
-      if (!EqualValues.empty()) {
-        for (unsigned i = 0, e = EqualValues.size(); i != e; ++i)
-          if (isa<Constant>(EqualValues[i])) {
-            AI->replaceAllUsesWith(EqualValues[i]);
-            ++NumArgsRepl;
-            Changed = true;
-            break;
-          }
-        EqualValues.clear();
-      }
-    }
-
-  // Traverse the CFG of the function in dominator order, so that we see each
-  // instruction after we see its operands.
-  for (df_iterator<DomTreeNode*> DI = df_begin(DT.getRootNode()),
-         E = df_end(DT.getRootNode()); DI != E; ++DI) {
-    BasicBlock *BB = DI->getBlock();
-
-    // Remember which instructions we've seen in this basic block as we scan.
-    std::set<Instruction*> BlockInsts;
-
-    for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ) {
-      Instruction *Inst = I++;
-
-      if (Constant *C = ConstantFoldInstruction(Inst)) {
-        ReplaceInstructionWith(Inst, C);
-      } else if (Inst->getType() != Type::VoidTy) {
-        // If this instruction computes a value, try to fold together common
-        // instructions that compute it.
-        //
-        VN.getEqualNumberNodes(Inst, EqualValues);
-
-        // If this instruction computes a value that is already computed
-        // elsewhere, try to recycle the old value.
-        if (!EqualValues.empty()) {
-          if (Inst == &*BB->begin())
-            I = BB->end();
-          else {
-            I = Inst; --I;
-          }
-
-          // First check to see if we were able to value number this instruction
-          // to a non-instruction value.  If so, prefer that value over other
-          // instructions which may compute the same thing.
-          for (unsigned i = 0, e = EqualValues.size(); i != e; ++i)
-            if (!isa<Instruction>(EqualValues[i])) {
-              ++NumNonInsts;      // Keep track of # of insts repl with values
-
-              // Change all users of Inst to use the replacement and remove it
-              // from the program.
-              ReplaceInstructionWith(Inst, EqualValues[i]);
-              Inst = 0;
-              EqualValues.clear();  // don't enter the next loop
-              break;
-            }
-
-          // If there were no non-instruction values that this instruction
-          // produces, find a dominating instruction that produces the same
-          // value.  If we find one, use it's value instead of ours.
-          for (unsigned i = 0, e = EqualValues.size(); i != e; ++i) {
-            Instruction *OtherI = cast<Instruction>(EqualValues[i]);
-            bool Dominates = false;
-            if (OtherI->getParent() == BB)
-              Dominates = BlockInsts.count(OtherI);
-            else
-              Dominates = DT.dominates(OtherI->getParent(), BB);
-
-            if (Dominates) {
-              // Okay, we found an instruction with the same value as this one
-              // and that dominates this one.  Replace this instruction with the
-              // specified one.
-              ReplaceInstructionWith(Inst, OtherI);
-              Inst = 0;
-              break;
-            }
-          }
-
-          EqualValues.clear();
-
-          if (Inst) {
-            I = Inst; ++I;             // Deleted no instructions
-          } else if (I == BB->end()) { // Deleted first instruction
-            I = BB->begin();
-          } else {                     // Deleted inst in middle of block.
-            ++I;
-          }
-        }
-
-        if (Inst)
-          BlockInsts.insert(Inst);
-      }
-    }
-  }
-
-  // When the worklist is empty, return whether or not we changed anything...
-  return Changed;
-}
-
-
-void GCSE::ReplaceInstructionWith(Instruction *I, Value *V) {
-  if (isa<LoadInst>(I))
-    ++NumLoadRemoved; // Keep track of loads eliminated
-  if (isa<CallInst>(I))
-    ++NumCallRemoved; // Keep track of calls eliminated
-  ++NumInstRemoved;   // Keep track of number of insts eliminated
-
-  // Update value numbering
-  getAnalysis<ValueNumbering>().deleteValue(I);
-
-  I->replaceAllUsesWith(V);
-
-  if (InvokeInst *II = dyn_cast<InvokeInst>(I)) {
-    // Removing an invoke instruction requires adding a branch to the normal
-    // destination and removing PHI node entries in the exception destination.
-    BranchInst::Create(II->getNormalDest(), II);
-    II->getUnwindDest()->removePredecessor(II->getParent());
-  }
-
-  // Erase the instruction from the program.
-  I->eraseFromParent();
-}