Remove unneeded RegionSimplify pass.

We now support regions with multiple entries and multiple exits natively.
Regions are not needed to be simplified to single entry and single exit.

We need to XFAIL two test cases as this change increases the scop coverage
and uncoveres two failures in the independent blocks pass. The first failure
will be fixed in a subsequent commit, the second one is in the non-default
-polly-codegen-scev mode and still needs to be fixed.

Contributed-by: Star Tan <tanmx_star@yeah.net>
llvm-svn: 179673

1 files changed, 0 insertions, 223 deletions

diff --git a/polly/lib/RegionSimplify.cpp b/polly/lib/RegionSimplify.cpp
deleted file mode 100644
index f4274250e17..00000000000
--- a/polly/lib/RegionSimplify.cpp
+++ /dev/null
@@ -1,223 +0,0 @@
-//===- RegionSimplify.cpp -------------------------------------------------===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// This file converts refined regions detected by the RegionInfo analysis
-// into simple regions.
-//
-//===----------------------------------------------------------------------===//
-
-#include "polly/LinkAllPasses.h"
-
-#include "llvm/IR/Instructions.h"
-#include "llvm/ADT/Statistic.h"
-#include "llvm/Analysis/AliasAnalysis.h"
-#include "llvm/Analysis/Dominators.h"
-#include "llvm/Analysis/LoopInfo.h"
-#include "llvm/Analysis/RegionPass.h"
-#include "llvm/Analysis/RegionInfo.h"
-#include "llvm/Transforms/Scalar.h"
-#include "llvm/Transforms/Utils/BasicBlockUtils.h"
-
-#define DEBUG_TYPE "region-simplify"
-#include "llvm/Support/Debug.h"
-
-using namespace llvm;
-
-STATISTIC(NumEntries, "The # of created entry edges");
-STATISTIC(NumExits, "The # of created exit edges");
-
-namespace {
-class RegionSimplify : public RegionPass {
-  // Remember the modified region.
-  Region *r;
-  void createSingleEntryEdge(Region *R);
-  void createSingleExitEdge(Region *R);
-
-public:
-  static char ID;
-  explicit RegionSimplify() : RegionPass(ID), r(0) {}
-
-  virtual void print(raw_ostream &O, const Module *M) const;
-
-  virtual bool runOnRegion(Region *R, RGPassManager &RGM);
-  virtual void getAnalysisUsage(AnalysisUsage &AU) const;
-};
-}
-
-char RegionSimplify::ID = 0;
-
-namespace polly {
-Pass *createRegionSimplifyPass() { return new RegionSimplify(); }
-}
-
-void RegionSimplify::print(raw_ostream &O, const Module *M) const {
-  if (r == 0)
-    return;
-
-  BasicBlock *enteringBlock = r->getEnteringBlock();
-  BasicBlock *exitingBlock = r->getExitingBlock();
-
-  O << "Region: " << r->getNameStr() << " Edges:\t";
-
-  if (enteringBlock)
-    O << "Entering: [" << enteringBlock->getName() << " -> "
-      << r->getEntry()->getName() << "], ";
-
-  if (exitingBlock) {
-    O << "Exiting: [" << exitingBlock->getName() << " -> ";
-    if (r->getExit())
-      O << r->getExit()->getName();
-    else
-      O << "<return>";
-    O << "]";
-  }
-
-  O << "\n";
-}
-
-void RegionSimplify::getAnalysisUsage(AnalysisUsage &AU) const {
-  // Function SplitBlockPredecessors currently updates/preserves AliasAnalysis,
-  /// DominatorTree, LoopInfo, and LCCSA but no other analyses.
-  //AU.addPreserved<AliasAnalysis>(); Break SCEV-AA
-  AU.addPreserved<DominatorTree>();
-  AU.addPreserved<LoopInfo>();
-  AU.addPreservedID(LCSSAID);
-
-  AU.addPreserved<RegionInfo>();
-  AU.addRequired<RegionInfo>();
-}
-
-// createSingleEntryEdge - Split the entry basic block of the given
-// region after the last PHINode to form a single entry edge.
-void RegionSimplify::createSingleEntryEdge(Region *R) {
-  BasicBlock *oldEntry = R->getEntry();
-  SmallVector<BasicBlock *, 4> Preds;
-  for (pred_iterator PI = pred_begin(oldEntry), PE = pred_end(oldEntry);
-       PI != PE; ++PI)
-    if (!R->contains(*PI))
-      Preds.push_back(*PI);
-
-  assert(Preds.size() && "This region has already a single entry edge");
-
-  BasicBlock *newEntry =
-      SplitBlockPredecessors(oldEntry, Preds, ".single_entry", this);
-
-  RegionInfo *RI = &getAnalysis<RegionInfo>();
-  // We do not update entry node for children of this region.
-  // This make it easier to extract children regions because they do not share
-  // the entry node with their parents.
-  // all parent regions whose entry is oldEntry are updated with newEntry
-  Region *r = R->getParent();
-
-  // Put the new entry to R's parent.
-  RI->setRegionFor(newEntry, r);
-
-  while (r->getEntry() == oldEntry && !r->isTopLevelRegion()) {
-    r->replaceEntry(newEntry);
-    r = r->getParent();
-  }
-
-  // We do not update exit node for children of this region for the same reason
-  // of not updating entry node.
-  // All other regions whose exit is oldEntry are updated with new exit node
-  r = RI->getTopLevelRegion();
-  std::vector<Region *> RQ;
-  RQ.push_back(r);
-
-  while (!RQ.empty()) {
-    r = RQ.back();
-    RQ.pop_back();
-
-    for (Region::const_iterator RI = r->begin(), RE = r->end(); RI != RE; ++RI)
-      RQ.push_back(*RI);
-
-    if (r->getExit() == oldEntry && !R->contains(r))
-      r->replaceExit(newEntry);
-  }
-
-}
-
-// createSingleExitEdge - Split the exit basic of the given region
-// to form a single exit edge.
-void RegionSimplify::createSingleExitEdge(Region *R) {
-  BasicBlock *oldExit = R->getExit();
-
-  SmallVector<BasicBlock *, 4> Preds;
-  for (pred_iterator PI = pred_begin(oldExit), PE = pred_end(oldExit); PI != PE;
-       ++PI)
-    if (R->contains(*PI))
-      Preds.push_back(*PI);
-
-  DEBUG(dbgs() << "Going to create single exit for:\n");
-  DEBUG(R->print(dbgs(), true, 0, Region::PrintRN));
-  BasicBlock *newExit =
-      SplitBlockPredecessors(oldExit, Preds, ".single_exit", this);
-  RegionInfo *RI = &getAnalysis<RegionInfo>();
-
-  // We do not need to update entry nodes because this split happens inside
-  // this region and it affects only this region and all of its children.
-  // The new split node belongs to this region
-  RI->setRegionFor(newExit, R);
-  DEBUG(dbgs() << "Adding new exiting block: " << newExit->getName() << '\n');
-
-  // all children of this region whose exit is oldExit is changed to newExit
-  std::vector<Region *> RQ;
-  for (Region::const_iterator RI = R->begin(), RE = R->end(); RI != RE; ++RI)
-    RQ.push_back(*RI);
-
-  while (!RQ.empty()) {
-    R = RQ.back();
-    RQ.pop_back();
-
-    if (R->getExit() != oldExit)
-      continue;
-
-    for (Region::const_iterator RI = R->begin(), RE = R->end(); RI != RE; ++RI)
-      RQ.push_back(*RI);
-
-    R->replaceExit(newExit);
-    DEBUG(dbgs() << "Replacing exit for:\n");
-    DEBUG(R->print(dbgs(), true, 0, Region::PrintRN));
-  }
-
-  DEBUG(dbgs() << "After split exit:\n");
-  DEBUG(R->print(dbgs(), true, 0, Region::PrintRN));
-}
-
-bool RegionSimplify::runOnRegion(Region *R, RGPassManager &RGM) {
-  r = 0;
-
-  if (!R->isTopLevelRegion()) {
-
-    // split entry node if the region has multiple entry edges
-    if (!(R->getEnteringBlock()) &&
-        (pred_begin(R->getEntry()) != pred_end(R->getEntry()))) {
-      createSingleEntryEdge(R);
-      r = R;
-      ++NumEntries;
-    }
-
-    // split exit node if the region has multiple exit edges
-    if (!(R->getExitingBlock())) {
-      createSingleExitEdge(R);
-      r = R;
-      ++NumExits;
-    }
-  }
-
-  return r != 0;
-}
-
-INITIALIZE_PASS_BEGIN(RegionSimplify, "polly-region-simplify",
-                      "Transform refined regions into simple regions", false,
-                      false);
-INITIALIZE_PASS_DEPENDENCY(RegionInfo);
-INITIALIZE_PASS_END(RegionSimplify, "polly-region-simplify",
-                    "Transform refined regions into simple regions", false,
-                    false)