1 files changed, 0 insertions, 291 deletions
diff --git a/lib/Analysis/LoopVR.cpp b/lib/Analysis/LoopVR.cpp
deleted file mode 100644
index ae715ac..0000000
--- a/lib/Analysis/LoopVR.cpp
+++ /dev/null
@@ -1,291 +0,0 @@
-//===- LoopVR.cpp - Value Range analysis driven by loop information -------===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// FIXME: What does this do?
-//
-//===----------------------------------------------------------------------===//
-
-#define DEBUG_TYPE "loopvr"
-#include "llvm/Analysis/LoopVR.h"
-#include "llvm/Constants.h"
-#include "llvm/Instructions.h"
-#include "llvm/Analysis/ScalarEvolutionExpressions.h"
-#include "llvm/Assembly/Writer.h"
-#include "llvm/Support/CFG.h"
-#include "llvm/Support/Debug.h"
-#include "llvm/Support/raw_ostream.h"
-using namespace llvm;
-
-char LoopVR::ID = 0;
-static RegisterPass<LoopVR> X("loopvr", "Loop Value Ranges", false, true);
-
-/// getRange - determine the range for a particular SCEV within a given Loop
-ConstantRange LoopVR::getRange(const SCEV* S, Loop *L, ScalarEvolution &SE) {
-  const SCEV* T = SE.getBackedgeTakenCount(L);
-  if (isa<SCEVCouldNotCompute>(T))
-    return ConstantRange(cast<IntegerType>(S->getType())->getBitWidth(), true);
-
-  T = SE.getTruncateOrZeroExtend(T, S->getType());
-  return getRange(S, T, SE);
-}
-
-/// getRange - determine the range for a particular SCEV with a given trip count
-ConstantRange LoopVR::getRange(const SCEV* S, const SCEV* T, ScalarEvolution &SE){
-
-  if (const SCEVConstant *C = dyn_cast<SCEVConstant>(S))
-    return ConstantRange(C->getValue()->getValue());
-
-  ConstantRange FullSet(cast<IntegerType>(S->getType())->getBitWidth(), true);
-
-  // {x,+,y,+,...z}. We detect overflow by checking the size of the set after
-  // summing the upper and lower.
-  if (const SCEVAddExpr *Add = dyn_cast<SCEVAddExpr>(S)) {
-    ConstantRange X = getRange(Add->getOperand(0), T, SE);
-    if (X.isFullSet()) return FullSet;
-    for (unsigned i = 1, e = Add->getNumOperands(); i != e; ++i) {
-      ConstantRange Y = getRange(Add->getOperand(i), T, SE);
-      if (Y.isFullSet()) return FullSet;
-
-      APInt Spread_X = X.getSetSize(), Spread_Y = Y.getSetSize();
-      APInt NewLower = X.getLower() + Y.getLower();
-      APInt NewUpper = X.getUpper() + Y.getUpper() - 1;
-      if (NewLower == NewUpper)
-        return FullSet;
-
-      X = ConstantRange(NewLower, NewUpper);
-      if (X.getSetSize().ult(Spread_X) || X.getSetSize().ult(Spread_Y))
-        return FullSet; // we've wrapped, therefore, full set.
-    }
-    return X;
-  }
-
-  // {x,*,y,*,...,z}. In order to detect overflow, we use k*bitwidth where
-  // k is the number of terms being multiplied.
-  if (const SCEVMulExpr *Mul = dyn_cast<SCEVMulExpr>(S)) {
-    ConstantRange X = getRange(Mul->getOperand(0), T, SE);
-    if (X.isFullSet()) return FullSet;
-
-    const IntegerType *Ty = IntegerType::get(X.getBitWidth());
-    const IntegerType *ExTy = IntegerType::get(X.getBitWidth() *
-                                               Mul->getNumOperands());
-    ConstantRange XExt = X.zeroExtend(ExTy->getBitWidth());
-
-    for (unsigned i = 1, e = Mul->getNumOperands(); i != e; ++i) {
-      ConstantRange Y = getRange(Mul->getOperand(i), T, SE);
-      if (Y.isFullSet()) return FullSet;
-
-      ConstantRange YExt = Y.zeroExtend(ExTy->getBitWidth());
-      XExt = ConstantRange(XExt.getLower() * YExt.getLower(),
-                           ((XExt.getUpper()-1) * (YExt.getUpper()-1)) + 1);
-    }
-    return XExt.truncate(Ty->getBitWidth());
-  }
-
-  // X smax Y smax ... Z is: range(smax(X_smin, Y_smin, ..., Z_smin),
-  //                               smax(X_smax, Y_smax, ..., Z_smax))
-  // It doesn't matter if one of the SCEVs has FullSet because we're taking
-  // a maximum of the minimums across all of them.
-  if (const SCEVSMaxExpr *SMax = dyn_cast<SCEVSMaxExpr>(S)) {
-    ConstantRange X = getRange(SMax->getOperand(0), T, SE);
-    if (X.isFullSet()) return FullSet;
-
-    APInt smin = X.getSignedMin(), smax = X.getSignedMax();
-    for (unsigned i = 1, e = SMax->getNumOperands(); i != e; ++i) {
-      ConstantRange Y = getRange(SMax->getOperand(i), T, SE);
-      smin = APIntOps::smax(smin, Y.getSignedMin());
-      smax = APIntOps::smax(smax, Y.getSignedMax());
-    }
-    if (smax + 1 == smin) return FullSet;
-    return ConstantRange(smin, smax + 1);
-  }
-
-  // X umax Y umax ... Z is: range(umax(X_umin, Y_umin, ..., Z_umin),
-  //                               umax(X_umax, Y_umax, ..., Z_umax))
-  // It doesn't matter if one of the SCEVs has FullSet because we're taking
-  // a maximum of the minimums across all of them.
-  if (const SCEVUMaxExpr *UMax = dyn_cast<SCEVUMaxExpr>(S)) {
-    ConstantRange X = getRange(UMax->getOperand(0), T, SE);
-    if (X.isFullSet()) return FullSet;
-
-    APInt umin = X.getUnsignedMin(), umax = X.getUnsignedMax();
-    for (unsigned i = 1, e = UMax->getNumOperands(); i != e; ++i) {
-      ConstantRange Y = getRange(UMax->getOperand(i), T, SE);
-      umin = APIntOps::umax(umin, Y.getUnsignedMin());
-      umax = APIntOps::umax(umax, Y.getUnsignedMax());
-    }
-    if (umax + 1 == umin) return FullSet;
-    return ConstantRange(umin, umax + 1);
-  }
-
-  // L udiv R. Luckily, there's only ever 2 sides to a udiv.
-  if (const SCEVUDivExpr *UDiv = dyn_cast<SCEVUDivExpr>(S)) {
-    ConstantRange L = getRange(UDiv->getLHS(), T, SE);
-    ConstantRange R = getRange(UDiv->getRHS(), T, SE);
-    if (L.isFullSet() && R.isFullSet()) return FullSet;
-
-    if (R.getUnsignedMax() == 0) {
-      // RHS must be single-element zero. Return an empty set.
-      return ConstantRange(R.getBitWidth(), false);
-    }
-
-    APInt Lower = L.getUnsignedMin().udiv(R.getUnsignedMax());
-
-    APInt Upper;
-
-    if (R.getUnsignedMin() == 0) {
-      // Just because it contains zero, doesn't mean it will also contain one.
-      // Use maximalIntersectWith to get the right behaviour.
-      ConstantRange NotZero(APInt(L.getBitWidth(), 1),
-                            APInt::getNullValue(L.getBitWidth()));
-      R = R.maximalIntersectWith(NotZero);
-    }
- 
-    // But, the maximal intersection might still include zero. If it does, then
-    // we know it also included one.
-    if (R.contains(APInt::getNullValue(L.getBitWidth())))
-      Upper = L.getUnsignedMax();
-    else
-      Upper = L.getUnsignedMax().udiv(R.getUnsignedMin());
-
-    return ConstantRange(Lower, Upper);
-  }
-
-  // ConstantRange already implements the cast operators.
-
-  if (const SCEVZeroExtendExpr *ZExt = dyn_cast<SCEVZeroExtendExpr>(S)) {
-    T = SE.getTruncateOrZeroExtend(T, ZExt->getOperand()->getType());
-    ConstantRange X = getRange(ZExt->getOperand(), T, SE);
-    return X.zeroExtend(cast<IntegerType>(ZExt->getType())->getBitWidth());
-  }
-
-  if (const SCEVSignExtendExpr *SExt = dyn_cast<SCEVSignExtendExpr>(S)) {
-    T = SE.getTruncateOrZeroExtend(T, SExt->getOperand()->getType());
-    ConstantRange X = getRange(SExt->getOperand(), T, SE);
-    return X.signExtend(cast<IntegerType>(SExt->getType())->getBitWidth());
-  }
-
-  if (const SCEVTruncateExpr *Trunc = dyn_cast<SCEVTruncateExpr>(S)) {
-    T = SE.getTruncateOrZeroExtend(T, Trunc->getOperand()->getType());
-    ConstantRange X = getRange(Trunc->getOperand(), T, SE);
-    if (X.isFullSet()) return FullSet;
-    return X.truncate(cast<IntegerType>(Trunc->getType())->getBitWidth());
-  }
-
-  if (const SCEVAddRecExpr *AddRec = dyn_cast<SCEVAddRecExpr>(S)) {
-    const SCEVConstant *Trip = dyn_cast<SCEVConstant>(T);
-    if (!Trip) return FullSet;
-
-    if (AddRec->isAffine()) {
-      const SCEV* StartHandle = AddRec->getStart();
-      const SCEV* StepHandle = AddRec->getOperand(1);
-
-      const SCEVConstant *Step = dyn_cast<SCEVConstant>(StepHandle);
-      if (!Step) return FullSet;
-
-      uint32_t ExWidth = 2 * Trip->getValue()->getBitWidth();
-      APInt TripExt = Trip->getValue()->getValue(); TripExt.zext(ExWidth);
-      APInt StepExt = Step->getValue()->getValue(); StepExt.zext(ExWidth);
-      if ((TripExt * StepExt).ugt(APInt::getLowBitsSet(ExWidth, ExWidth >> 1)))
-        return FullSet;
-
-      const SCEV* EndHandle = SE.getAddExpr(StartHandle,
-                                           SE.getMulExpr(T, StepHandle));
-      const SCEVConstant *Start = dyn_cast<SCEVConstant>(StartHandle);
-      const SCEVConstant *End = dyn_cast<SCEVConstant>(EndHandle);
-      if (!Start || !End) return FullSet;
-
-      const APInt &StartInt = Start->getValue()->getValue();
-      const APInt &EndInt = End->getValue()->getValue();
-      const APInt &StepInt = Step->getValue()->getValue();
-
-      if (StepInt.isNegative()) {
-        if (EndInt == StartInt + 1) return FullSet;
-        return ConstantRange(EndInt, StartInt + 1);
-      } else {
-        if (StartInt == EndInt + 1) return FullSet;
-        return ConstantRange(StartInt, EndInt + 1);
-      }
-    }
-  }
-
-  // TODO: non-affine addrec, udiv, SCEVUnknown (narrowed from elsewhere)?
-
-  return FullSet;
-}
-
-bool LoopVR::runOnFunction(Function &F) { Map.clear(); return false; }
-
-void LoopVR::print(std::ostream &os, const Module *) const {
-  raw_os_ostream OS(os);
-  for (std::map<Value *, ConstantRange *>::const_iterator I = Map.begin(),
-       E = Map.end(); I != E; ++I) {
-    OS << *I->first << ": " << *I->second << '\n';
-  }
-}
-
-void LoopVR::releaseMemory() {
-  for (std::map<Value *, ConstantRange *>::iterator I = Map.begin(),
-       E = Map.end(); I != E; ++I) {
-    delete I->second;
-  }
-
-  Map.clear();  
-}
-
-ConstantRange LoopVR::compute(Value *V) {
-  if (ConstantInt *CI = dyn_cast<ConstantInt>(V))
-    return ConstantRange(CI->getValue());
-
-  Instruction *I = dyn_cast<Instruction>(V);
-  if (!I)
-    return ConstantRange(cast<IntegerType>(V->getType())->getBitWidth(), false);
-
-  LoopInfo &LI = getAnalysis<LoopInfo>();
-
-  Loop *L = LI.getLoopFor(I->getParent());
-  if (!L || L->isLoopInvariant(I))
-    return ConstantRange(cast<IntegerType>(V->getType())->getBitWidth(), false);
-
-  ScalarEvolution &SE = getAnalysis<ScalarEvolution>();
-
-  const SCEV* S = SE.getSCEV(I);
-  if (isa<SCEVUnknown>(S) || isa<SCEVCouldNotCompute>(S))
-    return ConstantRange(cast<IntegerType>(V->getType())->getBitWidth(), false);
-
-  return ConstantRange(getRange(S, L, SE));
-}
-
-ConstantRange LoopVR::get(Value *V) {
-  std::map<Value *, ConstantRange *>::iterator I = Map.find(V);
-  if (I == Map.end()) {
-    ConstantRange *CR = new ConstantRange(compute(V));
-    Map[V] = CR;
-    return *CR;
-  }
-
-  return *I->second;
-}
-
-void LoopVR::remove(Value *V) {
-  std::map<Value *, ConstantRange *>::iterator I = Map.find(V);
-  if (I != Map.end()) {
-    delete I->second;
-    Map.erase(I);
-  }
-}
-
-void LoopVR::narrow(Value *V, const ConstantRange &CR) {
-  if (CR.isFullSet()) return;
-
-  std::map<Value *, ConstantRange *>::iterator I = Map.find(V);
-  if (I == Map.end())
-    Map[V] = new ConstantRange(CR);
-  else
-    Map[V] = new ConstantRange(Map[V]->maximalIntersectWith(CR));
-}