Removes the NVPTXSplitBBatBar pass.

This pass is a historic remnant and actually causes less efficient code to be
generated in some cases.

llvm-svn: 204620

llvm/lib/Target/NVPTX/CMakeLists.txt

@@ -16,7 +16,6 @@ set(NVPTXCodeGen_sources
   NVPTXRegisterInfo.cpp
   NVPTXSubtarget.cpp
   NVPTXTargetMachine.cpp
-  NVPTXSplitBBatBar.cpp
   NVPTXLowerAggrCopies.cpp
   NVPTXutil.cpp
   NVPTXAllocaHoisting.cpp

llvm/lib/Target/NVPTX/NVPTXSplitBBatBar.cpp

@@ -1,73 +0,0 @@
-//===- NVPTXSplitBBatBar.cpp - Split BB at Barrier  --*- C++ -*--===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-// Split basic blocks so that a basic block that contains a barrier instruction
-// only contains the barrier instruction.
-//
-//===----------------------------------------------------------------------===//
-
-#include "NVPTXSplitBBatBar.h"
-#include "NVPTXUtilities.h"
-#include "llvm/IR/Function.h"
-#include "llvm/IR/InstIterator.h"
-#include "llvm/IR/Instructions.h"
-#include "llvm/IR/IntrinsicInst.h"
-#include "llvm/IR/Intrinsics.h"
-
-using namespace llvm;
-
-namespace llvm { FunctionPass *createSplitBBatBarPass(); }
-
-char NVPTXSplitBBatBar::ID = 0;
-
-bool NVPTXSplitBBatBar::runOnFunction(Function &F) {
-
-  SmallVector<Instruction *, 4> SplitPoints;
-  bool changed = false;
-
-  // Collect all the split points in SplitPoints
-  for (Function::iterator BI = F.begin(), BE = F.end(); BI != BE; ++BI) {
-    BasicBlock::iterator IB = BI->begin();
-    BasicBlock::iterator II = IB;
-    BasicBlock::iterator IE = BI->end();
-
-    // Skit the first instruction. No splitting is needed at this
-    // point even if this is a bar.
-    while (II != IE) {
-      if (IntrinsicInst *inst = dyn_cast<IntrinsicInst>(II)) {
-        Intrinsic::ID id = inst->getIntrinsicID();
-        // If this is a barrier, split at this instruction
-        // and the next instruction.
-        if (llvm::isBarrierIntrinsic(id)) {
-          if (II != IB)
-            SplitPoints.push_back(II);
-          II++;
-          if ((II != IE) && (!II->isTerminator())) {
-            SplitPoints.push_back(II);
-            II++;
-          }
-          continue;
-        }
-      }
-      II++;
-    }
-  }
-
-  for (unsigned i = 0; i != SplitPoints.size(); i++) {
-    changed = true;
-    Instruction *inst = SplitPoints[i];
-    inst->getParent()->splitBasicBlock(inst, "bar_split");
-  }
-
-  return changed;
-}
-
-// This interface will most likely not be necessary, because this pass will
-// not be invoked by the driver, but will be used as a prerequisite to
-// another pass.
-FunctionPass *llvm::createSplitBBatBarPass() { return new NVPTXSplitBBatBar(); }

llvm/lib/Target/NVPTX/NVPTXSplitBBatBar.h

@@ -1,42 +0,0 @@
-//===-- llvm/lib/Target/NVPTX/NVPTXSplitBBatBar.h ---------------*- C++ -*-===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// This file contains the declaration of the NVIDIA specific declarations
-// for splitting basic blocks at barrier instructions.
-//
-//===----------------------------------------------------------------------===//
-
-#ifndef NVPTX_SPLIT_BB_AT_BAR_H
-#define NVPTX_SPLIT_BB_AT_BAR_H
-
-#include "llvm/CodeGen/MachineFunctionAnalysis.h"
-#include "llvm/Pass.h"
-
-namespace llvm {
-
-// actual analysis class, which is a functionpass
-struct NVPTXSplitBBatBar : public FunctionPass {
-  static char ID;
-
-  NVPTXSplitBBatBar() : FunctionPass(ID) {}
-  void getAnalysisUsage(AnalysisUsage &AU) const {
-    AU.addPreserved("stack-protector");
-    AU.addPreserved<MachineFunctionAnalysis>();
-  }
-  virtual bool runOnFunction(Function &F);
-
-  virtual const char *getPassName() const {
-    return "Split basic blocks at barrier";
-  }
-};
-
-extern FunctionPass *createSplitBBatBarPass();
-}
-
-#endif //NVPTX_SPLIT_BB_AT_BAR_H

llvm/lib/Target/NVPTX/NVPTXTargetMachine.cpp

@@ -16,7 +16,6 @@
 #include "NVPTX.h"
 #include "NVPTXAllocaHoisting.h"
 #include "NVPTXLowerAggrCopies.h"
-#include "NVPTXSplitBBatBar.h"
 #include "llvm/ADT/OwningPtr.h"
 #include "llvm/Analysis/Passes.h"
 #include "llvm/CodeGen/AsmPrinter.h"
@@ -145,7 +144,6 @@ void NVPTXPassConfig::addIRPasses() {
 
 bool NVPTXPassConfig::addInstSelector() {
   addPass(createLowerAggrCopies());
-  addPass(createSplitBBatBarPass());
   addPass(createAllocaHoisting());
   addPass(createNVPTXISelDag(getNVPTXTargetMachine(), getOptLevel()));
   return false;