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diff --git a/contrib/llvm/lib/Transforms/Scalar/LoopUnrollPass.cpp b/contrib/llvm/lib/Transforms/Scalar/LoopUnrollPass.cpp
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+++ b/contrib/llvm/lib/Transforms/Scalar/LoopUnrollPass.cpp
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+//===-- LoopUnroll.cpp - Loop unroller pass -------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This pass implements a simple loop unroller.  It works best when loops have
+// been canonicalized by the -indvars pass, allowing it to determine the trip
+// counts of loops easily.
+//===----------------------------------------------------------------------===//
+
+#define DEBUG_TYPE "loop-unroll"
+#include "llvm/IntrinsicInst.h"
+#include "llvm/Transforms/Scalar.h"
+#include "llvm/Analysis/LoopPass.h"
+#include "llvm/Analysis/CodeMetrics.h"
+#include "llvm/Analysis/ScalarEvolution.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/Transforms/Utils/UnrollLoop.h"
+#include "llvm/Target/TargetData.h"
+#include <climits>
+
+using namespace llvm;
+
+static cl::opt<unsigned>
+UnrollThreshold("unroll-threshold", cl::init(150), cl::Hidden,
+  cl::desc("The cut-off point for automatic loop unrolling"));
+
+static cl::opt<unsigned>
+UnrollCount("unroll-count", cl::init(0), cl::Hidden,
+  cl::desc("Use this unroll count for all loops, for testing purposes"));
+
+static cl::opt<bool>
+UnrollAllowPartial("unroll-allow-partial", cl::init(false), cl::Hidden,
+  cl::desc("Allows loops to be partially unrolled until "
+           "-unroll-threshold loop size is reached."));
+
+static cl::opt<bool>
+UnrollRuntime("unroll-runtime", cl::ZeroOrMore, cl::init(false), cl::Hidden,
+  cl::desc("Unroll loops with run-time trip counts"));
+
+namespace {
+  class LoopUnroll : public LoopPass {
+  public:
+    static char ID; // Pass ID, replacement for typeid
+    LoopUnroll(int T = -1, int C = -1,  int P = -1) : LoopPass(ID) {
+      CurrentThreshold = (T == -1) ? UnrollThreshold : unsigned(T);
+      CurrentCount = (C == -1) ? UnrollCount : unsigned(C);
+      CurrentAllowPartial = (P == -1) ? UnrollAllowPartial : (bool)P;
+
+      UserThreshold = (T != -1) || (UnrollThreshold.getNumOccurrences() > 0);
+
+      initializeLoopUnrollPass(*PassRegistry::getPassRegistry());
+    }
+
+    /// A magic value for use with the Threshold parameter to indicate
+    /// that the loop unroll should be performed regardless of how much
+    /// code expansion would result.
+    static const unsigned NoThreshold = UINT_MAX;
+
+    // Threshold to use when optsize is specified (and there is no
+    // explicit -unroll-threshold).
+    static const unsigned OptSizeUnrollThreshold = 50;
+
+    // Default unroll count for loops with run-time trip count if
+    // -unroll-count is not set
+    static const unsigned UnrollRuntimeCount = 8;
+
+    unsigned CurrentCount;
+    unsigned CurrentThreshold;
+    bool     CurrentAllowPartial;
+    bool     UserThreshold;        // CurrentThreshold is user-specified.
+
+    bool runOnLoop(Loop *L, LPPassManager &LPM);
+
+    /// This transformation requires natural loop information & requires that
+    /// loop preheaders be inserted into the CFG...
+    ///
+    virtual void getAnalysisUsage(AnalysisUsage &AU) const {
+      AU.addRequired<LoopInfo>();
+      AU.addPreserved<LoopInfo>();
+      AU.addRequiredID(LoopSimplifyID);
+      AU.addPreservedID(LoopSimplifyID);
+      AU.addRequiredID(LCSSAID);
+      AU.addPreservedID(LCSSAID);
+      AU.addRequired<ScalarEvolution>();
+      AU.addPreserved<ScalarEvolution>();
+      // FIXME: Loop unroll requires LCSSA. And LCSSA requires dom info.
+      // If loop unroll does not preserve dom info then LCSSA pass on next
+      // loop will receive invalid dom info.
+      // For now, recreate dom info, if loop is unrolled.
+      AU.addPreserved<DominatorTree>();
+    }
+  };
+}
+
+char LoopUnroll::ID = 0;
+INITIALIZE_PASS_BEGIN(LoopUnroll, "loop-unroll", "Unroll loops", false, false)
+INITIALIZE_PASS_DEPENDENCY(LoopInfo)
+INITIALIZE_PASS_DEPENDENCY(LoopSimplify)
+INITIALIZE_PASS_DEPENDENCY(LCSSA)
+INITIALIZE_PASS_DEPENDENCY(ScalarEvolution)
+INITIALIZE_PASS_END(LoopUnroll, "loop-unroll", "Unroll loops", false, false)
+
+Pass *llvm::createLoopUnrollPass(int Threshold, int Count, int AllowPartial) {
+  return new LoopUnroll(Threshold, Count, AllowPartial);
+}
+
+/// ApproximateLoopSize - Approximate the size of the loop.
+static unsigned ApproximateLoopSize(const Loop *L, unsigned &NumCalls,
+                                    const TargetData *TD) {
+  CodeMetrics Metrics;
+  for (Loop::block_iterator I = L->block_begin(), E = L->block_end();
+       I != E; ++I)
+    Metrics.analyzeBasicBlock(*I, TD);
+  NumCalls = Metrics.NumInlineCandidates;
+
+  unsigned LoopSize = Metrics.NumInsts;
+
+  // Don't allow an estimate of size zero.  This would allows unrolling of loops
+  // with huge iteration counts, which is a compile time problem even if it's
+  // not a problem for code quality.
+  if (LoopSize == 0) LoopSize = 1;
+
+  return LoopSize;
+}
+
+bool LoopUnroll::runOnLoop(Loop *L, LPPassManager &LPM) {
+  LoopInfo *LI = &getAnalysis<LoopInfo>();
+  ScalarEvolution *SE = &getAnalysis<ScalarEvolution>();
+
+  BasicBlock *Header = L->getHeader();
+  DEBUG(dbgs() << "Loop Unroll: F[" << Header->getParent()->getName()
+        << "] Loop %" << Header->getName() << "\n");
+  (void)Header;
+
+  // Determine the current unrolling threshold.  While this is normally set
+  // from UnrollThreshold, it is overridden to a smaller value if the current
+  // function is marked as optimize-for-size, and the unroll threshold was
+  // not user specified.
+  unsigned Threshold = CurrentThreshold;
+  if (!UserThreshold &&
+      Header->getParent()->hasFnAttr(Attribute::OptimizeForSize))
+    Threshold = OptSizeUnrollThreshold;
+
+  // Find trip count and trip multiple if count is not available
+  unsigned TripCount = 0;
+  unsigned TripMultiple = 1;
+  // Find "latch trip count". UnrollLoop assumes that control cannot exit
+  // via the loop latch on any iteration prior to TripCount. The loop may exit
+  // early via an earlier branch.
+  BasicBlock *LatchBlock = L->getLoopLatch();
+  if (LatchBlock) {
+    TripCount = SE->getSmallConstantTripCount(L, LatchBlock);
+    TripMultiple = SE->getSmallConstantTripMultiple(L, LatchBlock);
+  }
+  // Use a default unroll-count if the user doesn't specify a value
+  // and the trip count is a run-time value.  The default is different
+  // for run-time or compile-time trip count loops.
+  unsigned Count = CurrentCount;
+  if (UnrollRuntime && CurrentCount == 0 && TripCount == 0)
+    Count = UnrollRuntimeCount;
+
+  if (Count == 0) {
+    // Conservative heuristic: if we know the trip count, see if we can
+    // completely unroll (subject to the threshold, checked below); otherwise
+    // try to find greatest modulo of the trip count which is still under
+    // threshold value.
+    if (TripCount == 0)
+      return false;
+    Count = TripCount;
+  }
+
+  // Enforce the threshold.
+  if (Threshold != NoThreshold) {
+    const TargetData *TD = getAnalysisIfAvailable<TargetData>();
+    unsigned NumInlineCandidates;
+    unsigned LoopSize = ApproximateLoopSize(L, NumInlineCandidates, TD);
+    DEBUG(dbgs() << "  Loop Size = " << LoopSize << "\n");
+    if (NumInlineCandidates != 0) {
+      DEBUG(dbgs() << "  Not unrolling loop with inlinable calls.\n");
+      return false;
+    }
+    uint64_t Size = (uint64_t)LoopSize*Count;
+    if (TripCount != 1 && Size > Threshold) {
+      DEBUG(dbgs() << "  Too large to fully unroll with count: " << Count
+            << " because size: " << Size << ">" << Threshold << "\n");
+      if (!CurrentAllowPartial && !(UnrollRuntime && TripCount == 0)) {
+        DEBUG(dbgs() << "  will not try to unroll partially because "
+              << "-unroll-allow-partial not given\n");
+        return false;
+      }
+      if (TripCount) {
+        // Reduce unroll count to be modulo of TripCount for partial unrolling
+        Count = Threshold / LoopSize;
+        while (Count != 0 && TripCount%Count != 0)
+          Count--;
+      }
+      else if (UnrollRuntime) {
+        // Reduce unroll count to be a lower power-of-two value
+        while (Count != 0 && Size > Threshold) {
+          Count >>= 1;
+          Size = LoopSize*Count;
+        }
+      }
+      if (Count < 2) {
+        DEBUG(dbgs() << "  could not unroll partially\n");
+        return false;
+      }
+      DEBUG(dbgs() << "  partially unrolling with count: " << Count << "\n");
+    }
+  }
+
+  // Unroll the loop.
+  if (!UnrollLoop(L, Count, TripCount, UnrollRuntime, TripMultiple, LI, &LPM))
+    return false;
+
+  return true;
+}