diff options
Diffstat (limited to 'lib/Analysis/ScalarEvolution.cpp')
-rw-r--r-- | lib/Analysis/ScalarEvolution.cpp | 194 |
1 files changed, 114 insertions, 80 deletions
diff --git a/lib/Analysis/ScalarEvolution.cpp b/lib/Analysis/ScalarEvolution.cpp index 83671d6eb9..1b3aae8789 100644 --- a/lib/Analysis/ScalarEvolution.cpp +++ b/lib/Analysis/ScalarEvolution.cpp @@ -204,7 +204,7 @@ bool SCEVCastExpr::dominates(BasicBlock *BB, DominatorTree *DT) const { // SCEVTruncates - Only allow the creation of one SCEVTruncateExpr for any // particular input. Don't use a SCEVHandle here, or else the object will // never be deleted! -static ManagedStatic<std::map<std::pair<SCEV*, const Type*>, +static ManagedStatic<std::map<std::pair<const SCEV*, const Type*>, SCEVTruncateExpr*> > SCEVTruncates; SCEVTruncateExpr::SCEVTruncateExpr(const SCEVHandle &op, const Type *ty) @@ -225,7 +225,7 @@ void SCEVTruncateExpr::print(raw_ostream &OS) const { // SCEVZeroExtends - Only allow the creation of one SCEVZeroExtendExpr for any // particular input. Don't use a SCEVHandle here, or else the object will never // be deleted! -static ManagedStatic<std::map<std::pair<SCEV*, const Type*>, +static ManagedStatic<std::map<std::pair<const SCEV*, const Type*>, SCEVZeroExtendExpr*> > SCEVZeroExtends; SCEVZeroExtendExpr::SCEVZeroExtendExpr(const SCEVHandle &op, const Type *ty) @@ -246,7 +246,7 @@ void SCEVZeroExtendExpr::print(raw_ostream &OS) const { // SCEVSignExtends - Only allow the creation of one SCEVSignExtendExpr for any // particular input. Don't use a SCEVHandle here, or else the object will never // be deleted! -static ManagedStatic<std::map<std::pair<SCEV*, const Type*>, +static ManagedStatic<std::map<std::pair<const SCEV*, const Type*>, SCEVSignExtendExpr*> > SCEVSignExtends; SCEVSignExtendExpr::SCEVSignExtendExpr(const SCEVHandle &op, const Type *ty) @@ -267,13 +267,12 @@ void SCEVSignExtendExpr::print(raw_ostream &OS) const { // SCEVCommExprs - Only allow the creation of one SCEVCommutativeExpr for any // particular input. Don't use a SCEVHandle here, or else the object will never // be deleted! -static ManagedStatic<std::map<std::pair<unsigned, std::vector<SCEV*> >, +static ManagedStatic<std::map<std::pair<unsigned, std::vector<const SCEV*> >, SCEVCommutativeExpr*> > SCEVCommExprs; SCEVCommutativeExpr::~SCEVCommutativeExpr() { - SCEVCommExprs->erase(std::make_pair(getSCEVType(), - std::vector<SCEV*>(Operands.begin(), - Operands.end()))); + std::vector<const SCEV*> SCEVOps(Operands.begin(), Operands.end()); + SCEVCommExprs->erase(std::make_pair(getSCEVType(), SCEVOps)); } void SCEVCommutativeExpr::print(raw_ostream &OS) const { @@ -329,7 +328,7 @@ bool SCEVCommutativeExpr::dominates(BasicBlock *BB, DominatorTree *DT) const { // SCEVUDivs - Only allow the creation of one SCEVUDivExpr for any particular // input. Don't use a SCEVHandle here, or else the object will never be // deleted! -static ManagedStatic<std::map<std::pair<SCEV*, SCEV*>, +static ManagedStatic<std::map<std::pair<const SCEV*, const SCEV*>, SCEVUDivExpr*> > SCEVUDivs; SCEVUDivExpr::~SCEVUDivExpr() { @@ -351,13 +350,13 @@ const Type *SCEVUDivExpr::getType() const { // SCEVAddRecExprs - Only allow the creation of one SCEVAddRecExpr for any // particular input. Don't use a SCEVHandle here, or else the object will never // be deleted! -static ManagedStatic<std::map<std::pair<const Loop *, std::vector<SCEV*> >, +static ManagedStatic<std::map<std::pair<const Loop *, + std::vector<const SCEV*> >, SCEVAddRecExpr*> > SCEVAddRecExprs; SCEVAddRecExpr::~SCEVAddRecExpr() { - SCEVAddRecExprs->erase(std::make_pair(L, - std::vector<SCEV*>(Operands.begin(), - Operands.end()))); + std::vector<const SCEV*> SCEVOps(Operands.begin(), Operands.end()); + SCEVAddRecExprs->erase(std::make_pair(L, SCEVOps)); } bool SCEVAddRecExpr::dominates(BasicBlock *BB, DominatorTree *DT) const { @@ -480,7 +479,7 @@ static void GroupByComplexity(std::vector<SCEVHandle> &Ops) { // be extremely short in practice. Note that we take this approach because we // do not want to depend on the addresses of the objects we are grouping. for (unsigned i = 0, e = Ops.size(); i != e-2; ++i) { - SCEV *S = Ops[i]; + const SCEV *S = Ops[i]; unsigned Complexity = S->getSCEVType(); // If there are any objects of the same complexity and same value as this @@ -919,9 +918,9 @@ SCEVHandle ScalarEvolution::getAddExpr(std::vector<SCEVHandle> &Ops) { // something is not already an operand of the multiply. If so, merge it into // the multiply. for (; Idx < Ops.size() && isa<SCEVMulExpr>(Ops[Idx]); ++Idx) { - SCEVMulExpr *Mul = cast<SCEVMulExpr>(Ops[Idx]); + const SCEVMulExpr *Mul = cast<SCEVMulExpr>(Ops[Idx]); for (unsigned MulOp = 0, e = Mul->getNumOperands(); MulOp != e; ++MulOp) { - SCEV *MulOpSCEV = Mul->getOperand(MulOp); + const SCEV *MulOpSCEV = Mul->getOperand(MulOp); for (unsigned AddOp = 0, e = Ops.size(); AddOp != e; ++AddOp) if (MulOpSCEV == Ops[AddOp] && !isa<SCEVConstant>(MulOpSCEV)) { // Fold W + X + (X * Y * Z) --> W + (X * ((Y*Z)+1)) @@ -952,7 +951,7 @@ SCEVHandle ScalarEvolution::getAddExpr(std::vector<SCEVHandle> &Ops) { for (unsigned OtherMulIdx = Idx+1; OtherMulIdx < Ops.size() && isa<SCEVMulExpr>(Ops[OtherMulIdx]); ++OtherMulIdx) { - SCEVMulExpr *OtherMul = cast<SCEVMulExpr>(Ops[OtherMulIdx]); + const SCEVMulExpr *OtherMul = cast<SCEVMulExpr>(Ops[OtherMulIdx]); // If MulOp occurs in OtherMul, we can fold the two multiplies // together. for (unsigned OMulOp = 0, e = OtherMul->getNumOperands(); @@ -995,7 +994,7 @@ SCEVHandle ScalarEvolution::getAddExpr(std::vector<SCEVHandle> &Ops) { // Scan all of the other operands to this add and add them to the vector if // they are loop invariant w.r.t. the recurrence. std::vector<SCEVHandle> LIOps; - SCEVAddRecExpr *AddRec = cast<SCEVAddRecExpr>(Ops[Idx]); + const SCEVAddRecExpr *AddRec = cast<SCEVAddRecExpr>(Ops[Idx]); for (unsigned i = 0, e = Ops.size(); i != e; ++i) if (Ops[i]->isLoopInvariant(AddRec->getLoop())) { LIOps.push_back(Ops[i]); @@ -1030,7 +1029,7 @@ SCEVHandle ScalarEvolution::getAddExpr(std::vector<SCEVHandle> &Ops) { for (unsigned OtherIdx = Idx+1; OtherIdx < Ops.size() && isa<SCEVAddRecExpr>(Ops[OtherIdx]);++OtherIdx) if (OtherIdx != Idx) { - SCEVAddRecExpr *OtherAddRec = cast<SCEVAddRecExpr>(Ops[OtherIdx]); + const SCEVAddRecExpr *OtherAddRec = cast<SCEVAddRecExpr>(Ops[OtherIdx]); if (AddRec->getLoop() == OtherAddRec->getLoop()) { // Other + {A,+,B} + {C,+,D} --> Other + {A+C,+,B+D} std::vector<SCEVHandle> NewOps(AddRec->op_begin(), AddRec->op_end()); @@ -1059,7 +1058,7 @@ SCEVHandle ScalarEvolution::getAddExpr(std::vector<SCEVHandle> &Ops) { // Okay, it looks like we really DO need an add expr. Check to see if we // already have one, otherwise create a new one. - std::vector<SCEV*> SCEVOps(Ops.begin(), Ops.end()); + std::vector<const SCEV*> SCEVOps(Ops.begin(), Ops.end()); SCEVCommutativeExpr *&Result = (*SCEVCommExprs)[std::make_pair(scAddExpr, SCEVOps)]; if (Result == 0) Result = new SCEVAddExpr(Ops); @@ -1143,7 +1142,7 @@ SCEVHandle ScalarEvolution::getMulExpr(std::vector<SCEVHandle> &Ops) { // Scan all of the other operands to this mul and add them to the vector if // they are loop invariant w.r.t. the recurrence. std::vector<SCEVHandle> LIOps; - SCEVAddRecExpr *AddRec = cast<SCEVAddRecExpr>(Ops[Idx]); + const SCEVAddRecExpr *AddRec = cast<SCEVAddRecExpr>(Ops[Idx]); for (unsigned i = 0, e = Ops.size(); i != e; ++i) if (Ops[i]->isLoopInvariant(AddRec->getLoop())) { LIOps.push_back(Ops[i]); @@ -1157,7 +1156,7 @@ SCEVHandle ScalarEvolution::getMulExpr(std::vector<SCEVHandle> &Ops) { std::vector<SCEVHandle> NewOps; NewOps.reserve(AddRec->getNumOperands()); if (LIOps.size() == 1) { - SCEV *Scale = LIOps[0]; + const SCEV *Scale = LIOps[0]; for (unsigned i = 0, e = AddRec->getNumOperands(); i != e; ++i) NewOps.push_back(getMulExpr(Scale, AddRec->getOperand(i))); } else { @@ -1188,10 +1187,10 @@ SCEVHandle ScalarEvolution::getMulExpr(std::vector<SCEVHandle> &Ops) { for (unsigned OtherIdx = Idx+1; OtherIdx < Ops.size() && isa<SCEVAddRecExpr>(Ops[OtherIdx]);++OtherIdx) if (OtherIdx != Idx) { - SCEVAddRecExpr *OtherAddRec = cast<SCEVAddRecExpr>(Ops[OtherIdx]); + const SCEVAddRecExpr *OtherAddRec = cast<SCEVAddRecExpr>(Ops[OtherIdx]); if (AddRec->getLoop() == OtherAddRec->getLoop()) { // F * G --> {A,+,B} * {C,+,D} --> {A*C,+,F*D + G*B + B*D} - SCEVAddRecExpr *F = AddRec, *G = OtherAddRec; + const SCEVAddRecExpr *F = AddRec, *G = OtherAddRec; SCEVHandle NewStart = getMulExpr(F->getStart(), G->getStart()); SCEVHandle B = F->getStepRecurrence(*this); @@ -1216,7 +1215,7 @@ SCEVHandle ScalarEvolution::getMulExpr(std::vector<SCEVHandle> &Ops) { // Okay, it looks like we really DO need an mul expr. Check to see if we // already have one, otherwise create a new one. - std::vector<SCEV*> SCEVOps(Ops.begin(), Ops.end()); + std::vector<const SCEV*> SCEVOps(Ops.begin(), Ops.end()); SCEVCommutativeExpr *&Result = (*SCEVCommExprs)[std::make_pair(scMulExpr, SCEVOps)]; if (Result == 0) @@ -1286,9 +1285,8 @@ SCEVHandle ScalarEvolution::getAddRecExpr(std::vector<SCEVHandle> &Operands, } } - SCEVAddRecExpr *&Result = - (*SCEVAddRecExprs)[std::make_pair(L, std::vector<SCEV*>(Operands.begin(), - Operands.end()))]; + std::vector<const SCEV*> SCEVOps(Operands.begin(), Operands.end()); + SCEVAddRecExpr *&Result = (*SCEVAddRecExprs)[std::make_pair(L, SCEVOps)]; if (Result == 0) Result = new SCEVAddRecExpr(Operands, L); return Result; } @@ -1366,7 +1364,7 @@ SCEVHandle ScalarEvolution::getSMaxExpr(std::vector<SCEVHandle> Ops) { // Okay, it looks like we really DO need an smax expr. Check to see if we // already have one, otherwise create a new one. - std::vector<SCEV*> SCEVOps(Ops.begin(), Ops.end()); + std::vector<const SCEV*> SCEVOps(Ops.begin(), Ops.end()); SCEVCommutativeExpr *&Result = (*SCEVCommExprs)[std::make_pair(scSMaxExpr, SCEVOps)]; if (Result == 0) Result = new SCEVSMaxExpr(Ops); @@ -1446,7 +1444,7 @@ SCEVHandle ScalarEvolution::getUMaxExpr(std::vector<SCEVHandle> Ops) { // Okay, it looks like we really DO need a umax expr. Check to see if we // already have one, otherwise create a new one. - std::vector<SCEV*> SCEVOps(Ops.begin(), Ops.end()); + std::vector<const SCEV*> SCEVOps(Ops.begin(), Ops.end()); SCEVCommutativeExpr *&Result = (*SCEVCommExprs)[std::make_pair(scUMaxExpr, SCEVOps)]; if (Result == 0) Result = new SCEVUMaxExpr(Ops); @@ -1467,34 +1465,6 @@ SCEVHandle ScalarEvolution::getUnknown(Value *V) { // Basic SCEV Analysis and PHI Idiom Recognition Code // -/// deleteValueFromRecords - This method should be called by the -/// client before it removes an instruction from the program, to make sure -/// that no dangling references are left around. -void ScalarEvolution::deleteValueFromRecords(Value *V) { - SmallVector<Value *, 16> Worklist; - - if (Scalars.erase(V)) { - if (PHINode *PN = dyn_cast<PHINode>(V)) - ConstantEvolutionLoopExitValue.erase(PN); - Worklist.push_back(V); - } - - while (!Worklist.empty()) { - Value *VV = Worklist.back(); - Worklist.pop_back(); - - for (Instruction::use_iterator UI = VV->use_begin(), UE = VV->use_end(); - UI != UE; ++UI) { - Instruction *Inst = cast<Instruction>(*UI); - if (Scalars.erase(Inst)) { - if (PHINode *PN = dyn_cast<PHINode>(VV)) - ConstantEvolutionLoopExitValue.erase(PN); - Worklist.push_back(Inst); - } - } - } -} - /// isSCEVable - Test if values of the given type are analyzable within /// the SCEV framework. This primarily includes integer types, and it /// can optionally include pointer types if the ScalarEvolution class @@ -1556,10 +1526,10 @@ bool ScalarEvolution::hasSCEV(Value *V) const { SCEVHandle ScalarEvolution::getSCEV(Value *V) { assert(isSCEVable(V->getType()) && "Value is not SCEVable!"); - std::map<Value*, SCEVHandle>::iterator I = Scalars.find(V); + std::map<SCEVCallbackVH, SCEVHandle>::iterator I = Scalars.find(V); if (I != Scalars.end()) return I->second; SCEVHandle S = createSCEV(V); - Scalars.insert(std::make_pair(V, S)); + Scalars.insert(std::make_pair(SCEVCallbackVH(V, this), S)); return S; } @@ -1648,7 +1618,8 @@ ScalarEvolution::getTruncateOrSignExtend(const SCEVHandle &V, void ScalarEvolution:: ReplaceSymbolicValueWithConcrete(Instruction *I, const SCEVHandle &SymName, const SCEVHandle &NewVal) { - std::map<Value*, SCEVHandle>::iterator SI = Scalars.find(I); + std::map<SCEVCallbackVH, SCEVHandle>::iterator SI = + Scalars.find(SCEVCallbackVH(I, this)); if (SI == Scalars.end()) return; SCEVHandle NV = @@ -1680,7 +1651,7 @@ SCEVHandle ScalarEvolution::createNodeForPHI(PHINode *PN) { SCEVHandle SymbolicName = getUnknown(PN); assert(Scalars.find(PN) == Scalars.end() && "PHI node already processed?"); - Scalars.insert(std::make_pair(PN, SymbolicName)); + Scalars.insert(std::make_pair(SCEVCallbackVH(PN, this), SymbolicName)); // Using this symbolic name for the PHI, analyze the value coming around // the back-edge. @@ -2131,9 +2102,20 @@ void ScalarEvolution::forgetLoopBackedgeTakenCount(const Loop *L) { /// PHI nodes in the given loop. This is used when the trip count of /// the loop may have changed. void ScalarEvolution::forgetLoopPHIs(const Loop *L) { - for (BasicBlock::iterator I = L->getHeader()->begin(); + BasicBlock *Header = L->getHeader(); + + SmallVector<Instruction *, 16> Worklist; + for (BasicBlock::iterator I = Header->begin(); PHINode *PN = dyn_cast<PHINode>(I); ++I) - deleteValueFromRecords(PN); + Worklist.push_back(PN); + + while (!Worklist.empty()) { + Instruction *I = Worklist.pop_back_val(); + if (Scalars.erase(I)) + for (Value::use_iterator UI = I->use_begin(), UE = I->use_end(); + UI != UE; ++UI) + Worklist.push_back(cast<Instruction>(UI)); + } } /// ComputeBackedgeTakenCount - Compute the number of times the backedge @@ -2384,7 +2366,7 @@ ComputeLoadConstantCompareBackedgeTakenCount(LoadInst *LI, Constant *RHS, // We can only recognize very limited forms of loop index expressions, in // particular, only affine AddRec's like {C1,+,C2}. - SCEVAddRecExpr *IdxExpr = dyn_cast<SCEVAddRecExpr>(Idx); + const SCEVAddRecExpr *IdxExpr = dyn_cast<SCEVAddRecExpr>(Idx); if (!IdxExpr || !IdxExpr->isAffine() || IdxExpr->isLoopInvariant(L) || !isa<SCEVConstant>(IdxExpr->getOperand(0)) || !isa<SCEVConstant>(IdxExpr->getOperand(1))) @@ -2605,7 +2587,7 @@ ComputeBackedgeTakenCountExhaustively(const Loop *L, Value *Cond, bool ExitWhen) /// getSCEVAtScope - Compute the value of the specified expression within the /// indicated loop (which may be null to indicate in no loop). If the /// expression cannot be evaluated, return UnknownValue. -SCEVHandle ScalarEvolution::getSCEVAtScope(SCEV *V, const Loop *L) { +SCEVHandle ScalarEvolution::getSCEVAtScope(const SCEV *V, const Loop *L) { // FIXME: this should be turned into a virtual method on SCEV! if (isa<SCEVConstant>(V)) return V; @@ -2847,13 +2829,13 @@ static SCEVHandle SolveLinEquationWithOverflow(const APInt &A, const APInt &B, static std::pair<SCEVHandle,SCEVHandle> SolveQuadraticEquation(const SCEVAddRecExpr *AddRec, ScalarEvolution &SE) { assert(AddRec->getNumOperands() == 3 && "This is not a quadratic chrec!"); - SCEVConstant *LC = dyn_cast<SCEVConstant>(AddRec->getOperand(0)); - SCEVConstant *MC = dyn_cast<SCEVConstant>(AddRec->getOperand(1)); - SCEVConstant *NC = dyn_cast<SCEVConstant>(AddRec->getOperand(2)); + const SCEVConstant *LC = dyn_cast<SCEVConstant>(AddRec->getOperand(0)); + const SCEVConstant *MC = dyn_cast<SCEVConstant>(AddRec->getOperand(1)); + const SCEVConstant *NC = dyn_cast<SCEVConstant>(AddRec->getOperand(2)); // We currently can only solve this if the coefficients are constants. if (!LC || !MC || !NC) { - SCEV *CNC = SE.getCouldNotCompute(); + const SCEV *CNC = SE.getCouldNotCompute(); return std::make_pair(CNC, CNC); } @@ -2889,7 +2871,7 @@ SolveQuadraticEquation(const SCEVAddRecExpr *AddRec, ScalarEvolution &SE) { APInt NegB(-B); APInt TwoA( A << 1 ); if (TwoA.isMinValue()) { - SCEV *CNC = SE.getCouldNotCompute(); + const SCEV *CNC = SE.getCouldNotCompute(); return std::make_pair(CNC, CNC); } @@ -2903,7 +2885,7 @@ SolveQuadraticEquation(const SCEVAddRecExpr *AddRec, ScalarEvolution &SE) { /// HowFarToZero - Return the number of times a backedge comparing the specified /// value to zero will execute. If not computable, return UnknownValue -SCEVHandle ScalarEvolution::HowFarToZero(SCEV *V, const Loop *L) { +SCEVHandle ScalarEvolution::HowFarToZero(const SCEV *V, const Loop *L) { // If the value is a constant if (const SCEVConstant *C = dyn_cast<SCEVConstant>(V)) { // If the value is already zero, the branch will execute zero times. @@ -2911,7 +2893,7 @@ SCEVHandle ScalarEvolution::HowFarToZero(SCEV *V, const Loop *L) { return UnknownValue; // Otherwise it will loop infinitely. } - SCEVAddRecExpr *AddRec = dyn_cast<SCEVAddRecExpr>(V); + const SCEVAddRecExpr *AddRec = dyn_cast<SCEVAddRecExpr>(V); if (!AddRec || AddRec->getLoop() != L) return UnknownValue; @@ -2953,8 +2935,8 @@ SCEVHandle ScalarEvolution::HowFarToZero(SCEV *V, const Loop *L) { // the quadratic equation to solve it. std::pair<SCEVHandle,SCEVHandle> Roots = SolveQuadraticEquation(AddRec, *this); - SCEVConstant *R1 = dyn_cast<SCEVConstant>(Roots.first); - SCEVConstant *R2 = dyn_cast<SCEVConstant>(Roots.second); + const SCEVConstant *R1 = dyn_cast<SCEVConstant>(Roots.first); + const SCEVConstant *R2 = dyn_cast<SCEVConstant>(Roots.second); if (R1) { #if 0 errs() << "HFTZ: " << *V << " - sol#1: " << *R1 @@ -2983,7 +2965,7 @@ SCEVHandle ScalarEvolution::HowFarToZero(SCEV *V, const Loop *L) { /// HowFarToNonZero - Return the number of times a backedge checking the /// specified value for nonzero will execute. If not computable, return /// UnknownValue -SCEVHandle ScalarEvolution::HowFarToNonZero(SCEV *V, const Loop *L) { +SCEVHandle ScalarEvolution::HowFarToNonZero(const SCEV *V, const Loop *L) { // Loops that look like: while (X == 0) are very strange indeed. We don't // handle them yet except for the trivial case. This could be expanded in the // future as needed. @@ -3029,7 +3011,7 @@ ScalarEvolution::getPredecessorWithUniqueSuccessorForBB(BasicBlock *BB) { /// expressions in loop trip counts. bool ScalarEvolution::isLoopGuardedByCond(const Loop *L, ICmpInst::Predicate Pred, - SCEV *LHS, SCEV *RHS) { + const SCEV *LHS, const SCEV *RHS) { BasicBlock *Preheader = L->getLoopPreheader(); BasicBlock *PreheaderDest = L->getHeader(); @@ -3133,11 +3115,12 @@ bool ScalarEvolution::isLoopGuardedByCond(const Loop *L, /// specified less-than comparison will execute. If not computable, return /// UnknownValue. ScalarEvolution::BackedgeTakenInfo ScalarEvolution:: -HowManyLessThans(SCEV *LHS, SCEV *RHS, const Loop *L, bool isSigned) { +HowManyLessThans(const SCEV *LHS, const SCEV *RHS, + const Loop *L, bool isSigned) { // Only handle: "ADDREC < LoopInvariant". if (!RHS->isLoopInvariant(L)) return UnknownValue; - SCEVAddRecExpr *AddRec = dyn_cast<SCEVAddRecExpr>(LHS); + const SCEVAddRecExpr *AddRec = dyn_cast<SCEVAddRecExpr>(LHS); if (!AddRec || AddRec->getLoop() != L) return UnknownValue; @@ -3304,8 +3287,8 @@ SCEVHandle SCEVAddRecExpr::getNumIterationsInRange(ConstantRange Range, // Next, solve the constructed addrec std::pair<SCEVHandle,SCEVHandle> Roots = SolveQuadraticEquation(cast<SCEVAddRecExpr>(NewAddRec), SE); - SCEVConstant *R1 = dyn_cast<SCEVConstant>(Roots.first); - SCEVConstant *R2 = dyn_cast<SCEVConstant>(Roots.second); + const SCEVConstant *R1 = dyn_cast<SCEVConstant>(Roots.first); + const SCEVConstant *R2 = dyn_cast<SCEVConstant>(Roots.second); if (R1) { // Pick the smallest positive root value. if (ConstantInt *CB = @@ -3347,6 +3330,57 @@ SCEVHandle SCEVAddRecExpr::getNumIterationsInRange(ConstantRange Range, //===----------------------------------------------------------------------===// +// SCEVCallbackVH Class Implementation +//===----------------------------------------------------------------------===// + +void SCEVCallbackVH::deleted() { + assert(SE && "SCEVCallbackVH called with a non-null ScalarEvolution!"); + if (PHINode *PN = dyn_cast<PHINode>(getValPtr())) + SE->ConstantEvolutionLoopExitValue.erase(PN); + SE->Scalars.erase(getValPtr()); + // this now dangles! +} + +void SCEVCallbackVH::allUsesReplacedWith(Value *) { + assert(SE && "SCEVCallbackVH called with a non-null ScalarEvolution!"); + + // Forget all the expressions associated with users of the old value, + // so that future queries will recompute the expressions using the new + // value. + SmallVector<User *, 16> Worklist; + Value *Old = getValPtr(); + bool DeleteOld = false; + for (Value::use_iterator UI = Old->use_begin(), UE = Old->use_end(); + UI != UE; ++UI) + Worklist.push_back(*UI); + while (!Worklist.empty()) { + User *U = Worklist.pop_back_val(); + // Deleting the Old value will cause this to dangle. Postpone + // that until everything else is done. + if (U == Old) { + DeleteOld = true; + continue; + } + if (PHINode *PN = dyn_cast<PHINode>(U)) + SE->ConstantEvolutionLoopExitValue.erase(PN); + if (SE->Scalars.erase(U)) + for (Value::use_iterator UI = U->use_begin(), UE = U->use_end(); + UI != UE; ++UI) + Worklist.push_back(*UI); + } + if (DeleteOld) { + if (PHINode *PN = dyn_cast<PHINode>(Old)) + SE->ConstantEvolutionLoopExitValue.erase(PN); + SE->Scalars.erase(Old); + // this now dangles! + } + // this may dangle! +} + +SCEVCallbackVH::SCEVCallbackVH(Value *V, ScalarEvolution *se) + : CallbackVH(V), SE(se) {} + +//===----------------------------------------------------------------------===// // ScalarEvolution Class Implementation //===----------------------------------------------------------------------===// |