| //===- ExprTypeConvert.cpp - Code to change an LLVM Expr Type -------------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file was developed by the LLVM research group and is distributed under |
| // the University of Illinois Open Source License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file implements the part of level raising that checks to see if it is |
| // possible to coerce an entire expression tree into a different type. If |
| // convertible, other routines from this file will do the conversion. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "TransformInternals.h" |
| #include "llvm/Constants.h" |
| #include "llvm/Instructions.h" |
| #include "llvm/ADT/STLExtras.h" |
| #include "llvm/Support/Debug.h" |
| #include <algorithm> |
| using namespace llvm; |
| |
| static bool OperandConvertibleToType(User *U, Value *V, const Type *Ty, |
| ValueTypeCache &ConvertedTypes, |
| const TargetData &TD); |
| |
| static void ConvertOperandToType(User *U, Value *OldVal, Value *NewVal, |
| ValueMapCache &VMC, const TargetData &TD); |
| |
| |
| // ExpressionConvertibleToType - Return true if it is possible |
| bool llvm::ExpressionConvertibleToType(Value *V, const Type *Ty, |
| ValueTypeCache &CTMap, const TargetData &TD) { |
| // Expression type must be holdable in a register. |
| if (!Ty->isFirstClassType()) |
| return false; |
| |
| ValueTypeCache::iterator CTMI = CTMap.find(V); |
| if (CTMI != CTMap.end()) return CTMI->second == Ty; |
| |
| // If it's a constant... all constants can be converted to a different |
| // type. |
| // |
| if (isa<Constant>(V) && !isa<GlobalValue>(V)) |
| return true; |
| |
| CTMap[V] = Ty; |
| if (V->getType() == Ty) return true; // Expression already correct type! |
| |
| Instruction *I = dyn_cast<Instruction>(V); |
| if (I == 0) return false; // Otherwise, we can't convert! |
| |
| switch (I->getOpcode()) { |
| case Instruction::Cast: |
| // We can convert the expr if the cast destination type is losslessly |
| // convertible to the requested type. |
| if (!Ty->isLosslesslyConvertibleTo(I->getType())) return false; |
| |
| // We also do not allow conversion of a cast that casts from a ptr to array |
| // of X to a *X. For example: cast [4 x %List *] * %val to %List * * |
| // |
| if (const PointerType *SPT = |
| dyn_cast<PointerType>(I->getOperand(0)->getType())) |
| if (const PointerType *DPT = dyn_cast<PointerType>(I->getType())) |
| if (const ArrayType *AT = dyn_cast<ArrayType>(SPT->getElementType())) |
| if (AT->getElementType() == DPT->getElementType()) |
| return false; |
| break; |
| |
| case Instruction::Add: |
| case Instruction::Sub: |
| if (!Ty->isInteger() && !Ty->isFloatingPoint()) return false; |
| if (!ExpressionConvertibleToType(I->getOperand(0), Ty, CTMap, TD) || |
| !ExpressionConvertibleToType(I->getOperand(1), Ty, CTMap, TD)) |
| return false; |
| break; |
| case Instruction::Shr: |
| if (!Ty->isInteger()) return false; |
| if (Ty->isSigned() != V->getType()->isSigned()) return false; |
| // FALL THROUGH |
| case Instruction::Shl: |
| if (!Ty->isInteger()) return false; |
| if (!ExpressionConvertibleToType(I->getOperand(0), Ty, CTMap, TD)) |
| return false; |
| break; |
| |
| case Instruction::Load: { |
| LoadInst *LI = cast<LoadInst>(I); |
| if (!ExpressionConvertibleToType(LI->getPointerOperand(), |
| PointerType::get(Ty), CTMap, TD)) |
| return false; |
| break; |
| } |
| case Instruction::PHI: { |
| PHINode *PN = cast<PHINode>(I); |
| // Be conservative if we find a giant PHI node. |
| if (PN->getNumIncomingValues() > 32) return false; |
| |
| for (unsigned i = 0; i < PN->getNumIncomingValues(); ++i) |
| if (!ExpressionConvertibleToType(PN->getIncomingValue(i), Ty, CTMap, TD)) |
| return false; |
| break; |
| } |
| |
| case Instruction::GetElementPtr: { |
| // GetElementPtr's are directly convertible to a pointer type if they have |
| // a number of zeros at the end. Because removing these values does not |
| // change the logical offset of the GEP, it is okay and fair to remove them. |
| // This can change this: |
| // %t1 = getelementptr %Hosp * %hosp, ubyte 4, ubyte 0 ; <%List **> |
| // %t2 = cast %List * * %t1 to %List * |
| // into |
| // %t2 = getelementptr %Hosp * %hosp, ubyte 4 ; <%List *> |
| // |
| GetElementPtrInst *GEP = cast<GetElementPtrInst>(I); |
| const PointerType *PTy = dyn_cast<PointerType>(Ty); |
| if (!PTy) return false; // GEP must always return a pointer... |
| const Type *PVTy = PTy->getElementType(); |
| |
| // Check to see if there are zero elements that we can remove from the |
| // index array. If there are, check to see if removing them causes us to |
| // get to the right type... |
| // |
| std::vector<Value*> Indices(GEP->idx_begin(), GEP->idx_end()); |
| const Type *BaseType = GEP->getPointerOperand()->getType(); |
| const Type *ElTy = 0; |
| |
| while (!Indices.empty() && |
| Indices.back() == Constant::getNullValue(Indices.back()->getType())){ |
| Indices.pop_back(); |
| ElTy = GetElementPtrInst::getIndexedType(BaseType, Indices, true); |
| if (ElTy == PVTy) |
| break; // Found a match!! |
| ElTy = 0; |
| } |
| |
| if (ElTy) break; // Found a number of zeros we can strip off! |
| |
| // Otherwise, it could be that we have something like this: |
| // getelementptr [[sbyte] *] * %reg115, long %reg138 ; [sbyte]** |
| // and want to convert it into something like this: |
| // getelemenptr [[int] *] * %reg115, long %reg138 ; [int]** |
| // |
| if (GEP->getNumOperands() == 2 && |
| PTy->getElementType()->isSized() && |
| TD.getTypeSize(PTy->getElementType()) == |
| TD.getTypeSize(GEP->getType()->getElementType())) { |
| const PointerType *NewSrcTy = PointerType::get(PVTy); |
| if (!ExpressionConvertibleToType(I->getOperand(0), NewSrcTy, CTMap, TD)) |
| return false; |
| break; |
| } |
| |
| return false; // No match, maybe next time. |
| } |
| |
| case Instruction::Call: { |
| if (isa<Function>(I->getOperand(0))) |
| return false; // Don't even try to change direct calls. |
| |
| // If this is a function pointer, we can convert the return type if we can |
| // convert the source function pointer. |
| // |
| const PointerType *PT = cast<PointerType>(I->getOperand(0)->getType()); |
| const FunctionType *FT = cast<FunctionType>(PT->getElementType()); |
| std::vector<const Type *> ArgTys(FT->param_begin(), FT->param_end()); |
| const FunctionType *NewTy = |
| FunctionType::get(Ty, ArgTys, FT->isVarArg()); |
| if (!ExpressionConvertibleToType(I->getOperand(0), |
| PointerType::get(NewTy), CTMap, TD)) |
| return false; |
| break; |
| } |
| default: |
| return false; |
| } |
| |
| // Expressions are only convertible if all of the users of the expression can |
| // have this value converted. This makes use of the map to avoid infinite |
| // recursion. |
| // |
| for (Value::use_iterator It = I->use_begin(), E = I->use_end(); It != E; ++It) |
| if (!OperandConvertibleToType(*It, I, Ty, CTMap, TD)) |
| return false; |
| |
| return true; |
| } |
| |
| |
| Value *llvm::ConvertExpressionToType(Value *V, const Type *Ty, |
| ValueMapCache &VMC, const TargetData &TD) { |
| if (V->getType() == Ty) return V; // Already where we need to be? |
| |
| ValueMapCache::ExprMapTy::iterator VMCI = VMC.ExprMap.find(V); |
| if (VMCI != VMC.ExprMap.end()) { |
| const Value *GV = VMCI->second; |
| const Type *GTy = VMCI->second->getType(); |
| assert(VMCI->second->getType() == Ty); |
| |
| if (Instruction *I = dyn_cast<Instruction>(V)) |
| ValueHandle IHandle(VMC, I); // Remove I if it is unused now! |
| |
| return VMCI->second; |
| } |
| |
| DEBUG(std::cerr << "CETT: " << (void*)V << " " << *V); |
| |
| Instruction *I = dyn_cast<Instruction>(V); |
| if (I == 0) { |
| Constant *CPV = cast<Constant>(V); |
| // Constants are converted by constant folding the cast that is required. |
| // We assume here that all casts are implemented for constant prop. |
| Value *Result = ConstantExpr::getCast(CPV, Ty); |
| // Add the instruction to the expression map |
| //VMC.ExprMap[V] = Result; |
| return Result; |
| } |
| |
| |
| BasicBlock *BB = I->getParent(); |
| std::string Name = I->getName(); if (!Name.empty()) I->setName(""); |
| Instruction *Res; // Result of conversion |
| |
| ValueHandle IHandle(VMC, I); // Prevent I from being removed! |
| |
| Constant *Dummy = Constant::getNullValue(Ty); |
| |
| switch (I->getOpcode()) { |
| case Instruction::Cast: |
| assert(VMC.NewCasts.count(ValueHandle(VMC, I)) == 0); |
| Res = new CastInst(I->getOperand(0), Ty, Name); |
| VMC.NewCasts.insert(ValueHandle(VMC, Res)); |
| break; |
| |
| case Instruction::Add: |
| case Instruction::Sub: |
| Res = BinaryOperator::create(cast<BinaryOperator>(I)->getOpcode(), |
| Dummy, Dummy, Name); |
| VMC.ExprMap[I] = Res; // Add node to expression eagerly |
| |
| Res->setOperand(0, ConvertExpressionToType(I->getOperand(0), Ty, VMC, TD)); |
| Res->setOperand(1, ConvertExpressionToType(I->getOperand(1), Ty, VMC, TD)); |
| break; |
| |
| case Instruction::Shl: |
| case Instruction::Shr: |
| Res = new ShiftInst(cast<ShiftInst>(I)->getOpcode(), Dummy, |
| I->getOperand(1), Name); |
| VMC.ExprMap[I] = Res; |
| Res->setOperand(0, ConvertExpressionToType(I->getOperand(0), Ty, VMC, TD)); |
| break; |
| |
| case Instruction::Load: { |
| LoadInst *LI = cast<LoadInst>(I); |
| |
| Res = new LoadInst(Constant::getNullValue(PointerType::get(Ty)), Name); |
| VMC.ExprMap[I] = Res; |
| Res->setOperand(0, ConvertExpressionToType(LI->getPointerOperand(), |
| PointerType::get(Ty), VMC, TD)); |
| assert(Res->getOperand(0)->getType() == PointerType::get(Ty)); |
| assert(Ty == Res->getType()); |
| assert(Res->getType()->isFirstClassType() && "Load of structure or array!"); |
| break; |
| } |
| |
| case Instruction::PHI: { |
| PHINode *OldPN = cast<PHINode>(I); |
| PHINode *NewPN = new PHINode(Ty, Name); |
| |
| VMC.ExprMap[I] = NewPN; // Add node to expression eagerly |
| while (OldPN->getNumOperands()) { |
| BasicBlock *BB = OldPN->getIncomingBlock(0); |
| Value *OldVal = OldPN->getIncomingValue(0); |
| ValueHandle OldValHandle(VMC, OldVal); |
| OldPN->removeIncomingValue(BB, false); |
| Value *V = ConvertExpressionToType(OldVal, Ty, VMC, TD); |
| NewPN->addIncoming(V, BB); |
| } |
| Res = NewPN; |
| break; |
| } |
| |
| case Instruction::GetElementPtr: { |
| // GetElementPtr's are directly convertible to a pointer type if they have |
| // a number of zeros at the end. Because removing these values does not |
| // change the logical offset of the GEP, it is okay and fair to remove them. |
| // This can change this: |
| // %t1 = getelementptr %Hosp * %hosp, ubyte 4, ubyte 0 ; <%List **> |
| // %t2 = cast %List * * %t1 to %List * |
| // into |
| // %t2 = getelementptr %Hosp * %hosp, ubyte 4 ; <%List *> |
| // |
| GetElementPtrInst *GEP = cast<GetElementPtrInst>(I); |
| |
| // Check to see if there are zero elements that we can remove from the |
| // index array. If there are, check to see if removing them causes us to |
| // get to the right type... |
| // |
| std::vector<Value*> Indices(GEP->idx_begin(), GEP->idx_end()); |
| const Type *BaseType = GEP->getPointerOperand()->getType(); |
| const Type *PVTy = cast<PointerType>(Ty)->getElementType(); |
| Res = 0; |
| while (!Indices.empty() && |
| Indices.back() == Constant::getNullValue(Indices.back()->getType())){ |
| Indices.pop_back(); |
| if (GetElementPtrInst::getIndexedType(BaseType, Indices, true) == PVTy) { |
| if (Indices.size() == 0) |
| Res = new CastInst(GEP->getPointerOperand(), BaseType); // NOOP CAST |
| else |
| Res = new GetElementPtrInst(GEP->getPointerOperand(), Indices, Name); |
| break; |
| } |
| } |
| |
| // Otherwise, it could be that we have something like this: |
| // getelementptr [[sbyte] *] * %reg115, uint %reg138 ; [sbyte]** |
| // and want to convert it into something like this: |
| // getelemenptr [[int] *] * %reg115, uint %reg138 ; [int]** |
| // |
| if (Res == 0) { |
| const PointerType *NewSrcTy = PointerType::get(PVTy); |
| std::vector<Value*> Indices(GEP->idx_begin(), GEP->idx_end()); |
| Res = new GetElementPtrInst(Constant::getNullValue(NewSrcTy), |
| Indices, Name); |
| VMC.ExprMap[I] = Res; |
| Res->setOperand(0, ConvertExpressionToType(I->getOperand(0), |
| NewSrcTy, VMC, TD)); |
| } |
| |
| |
| assert(Res && "Didn't find match!"); |
| break; |
| } |
| |
| case Instruction::Call: { |
| assert(!isa<Function>(I->getOperand(0))); |
| |
| // If this is a function pointer, we can convert the return type if we can |
| // convert the source function pointer. |
| // |
| const PointerType *PT = cast<PointerType>(I->getOperand(0)->getType()); |
| const FunctionType *FT = cast<FunctionType>(PT->getElementType()); |
| std::vector<const Type *> ArgTys(FT->param_begin(), FT->param_end()); |
| const FunctionType *NewTy = |
| FunctionType::get(Ty, ArgTys, FT->isVarArg()); |
| const PointerType *NewPTy = PointerType::get(NewTy); |
| if (Ty == Type::VoidTy) |
| Name = ""; // Make sure not to name calls that now return void! |
| |
| Res = new CallInst(Constant::getNullValue(NewPTy), |
| std::vector<Value*>(I->op_begin()+1, I->op_end()), |
| Name); |
| if (cast<CallInst>(I)->isTailCall()) |
| cast<CallInst>(Res)->setTailCall(); |
| cast<CallInst>(Res)->setCallingConv(cast<CallInst>(I)->getCallingConv()); |
| VMC.ExprMap[I] = Res; |
| Res->setOperand(0, ConvertExpressionToType(I->getOperand(0),NewPTy,VMC,TD)); |
| break; |
| } |
| default: |
| assert(0 && "Expression convertible, but don't know how to convert?"); |
| return 0; |
| } |
| |
| assert(Res->getType() == Ty && "Didn't convert expr to correct type!"); |
| |
| BB->getInstList().insert(I, Res); |
| |
| // Add the instruction to the expression map |
| VMC.ExprMap[I] = Res; |
| |
| |
| //// WTF is this code! FIXME: remove this. |
| unsigned NumUses = I->getNumUses(); |
| for (unsigned It = 0; It < NumUses; ) { |
| unsigned OldSize = NumUses; |
| Value::use_iterator UI = I->use_begin(); |
| std::advance(UI, It); |
| ConvertOperandToType(*UI, I, Res, VMC, TD); |
| NumUses = I->getNumUses(); |
| if (NumUses == OldSize) ++It; |
| } |
| |
| DEBUG(std::cerr << "ExpIn: " << (void*)I << " " << *I |
| << "ExpOut: " << (void*)Res << " " << *Res); |
| |
| return Res; |
| } |
| |
| |
| |
| // ValueConvertibleToType - Return true if it is possible |
| bool llvm::ValueConvertibleToType(Value *V, const Type *Ty, |
| ValueTypeCache &ConvertedTypes, |
| const TargetData &TD) { |
| ValueTypeCache::iterator I = ConvertedTypes.find(V); |
| if (I != ConvertedTypes.end()) return I->second == Ty; |
| ConvertedTypes[V] = Ty; |
| |
| // It is safe to convert the specified value to the specified type IFF all of |
| // the uses of the value can be converted to accept the new typed value. |
| // |
| if (V->getType() != Ty) { |
| for (Value::use_iterator I = V->use_begin(), E = V->use_end(); I != E; ++I) |
| if (!OperandConvertibleToType(*I, V, Ty, ConvertedTypes, TD)) |
| return false; |
| } |
| |
| return true; |
| } |
| |
| |
| |
| |
| |
| // OperandConvertibleToType - Return true if it is possible to convert operand |
| // V of User (instruction) U to the specified type. This is true iff it is |
| // possible to change the specified instruction to accept this. CTMap is a map |
| // of converted types, so that circular definitions will see the future type of |
| // the expression, not the static current type. |
| // |
| static bool OperandConvertibleToType(User *U, Value *V, const Type *Ty, |
| ValueTypeCache &CTMap, |
| const TargetData &TD) { |
| // if (V->getType() == Ty) return true; // Operand already the right type? |
| |
| // Expression type must be holdable in a register. |
| if (!Ty->isFirstClassType()) |
| return false; |
| |
| Instruction *I = dyn_cast<Instruction>(U); |
| if (I == 0) return false; // We can't convert! |
| |
| switch (I->getOpcode()) { |
| case Instruction::Cast: |
| assert(I->getOperand(0) == V); |
| // We can convert the expr if the cast destination type is losslessly |
| // convertible to the requested type. |
| // Also, do not change a cast that is a noop cast. For all intents and |
| // purposes it should be eliminated. |
| if (!Ty->isLosslesslyConvertibleTo(I->getOperand(0)->getType()) || |
| I->getType() == I->getOperand(0)->getType()) |
| return false; |
| |
| // Do not allow a 'cast ushort %V to uint' to have it's first operand be |
| // converted to a 'short' type. Doing so changes the way sign promotion |
| // happens, and breaks things. Only allow the cast to take place if the |
| // signedness doesn't change... or if the current cast is not a lossy |
| // conversion. |
| // |
| if (!I->getType()->isLosslesslyConvertibleTo(I->getOperand(0)->getType()) && |
| I->getOperand(0)->getType()->isSigned() != Ty->isSigned()) |
| return false; |
| |
| // We also do not allow conversion of a cast that casts from a ptr to array |
| // of X to a *X. For example: cast [4 x %List *] * %val to %List * * |
| // |
| if (const PointerType *SPT = |
| dyn_cast<PointerType>(I->getOperand(0)->getType())) |
| if (const PointerType *DPT = dyn_cast<PointerType>(I->getType())) |
| if (const ArrayType *AT = dyn_cast<ArrayType>(SPT->getElementType())) |
| if (AT->getElementType() == DPT->getElementType()) |
| return false; |
| return true; |
| |
| case Instruction::Add: |
| case Instruction::Sub: { |
| if (!Ty->isInteger() && !Ty->isFloatingPoint()) return false; |
| |
| Value *OtherOp = I->getOperand((V == I->getOperand(0)) ? 1 : 0); |
| return ValueConvertibleToType(I, Ty, CTMap, TD) && |
| ExpressionConvertibleToType(OtherOp, Ty, CTMap, TD); |
| } |
| case Instruction::SetEQ: |
| case Instruction::SetNE: { |
| Value *OtherOp = I->getOperand((V == I->getOperand(0)) ? 1 : 0); |
| return ExpressionConvertibleToType(OtherOp, Ty, CTMap, TD); |
| } |
| case Instruction::Shr: |
| if (Ty->isSigned() != V->getType()->isSigned()) return false; |
| // FALL THROUGH |
| case Instruction::Shl: |
| if (I->getOperand(1) == V) return false; // Cannot change shift amount type |
| if (!Ty->isInteger()) return false; |
| return ValueConvertibleToType(I, Ty, CTMap, TD); |
| |
| case Instruction::Free: |
| assert(I->getOperand(0) == V); |
| return isa<PointerType>(Ty); // Free can free any pointer type! |
| |
| case Instruction::Load: |
| // Cannot convert the types of any subscripts... |
| if (I->getOperand(0) != V) return false; |
| |
| if (const PointerType *PT = dyn_cast<PointerType>(Ty)) { |
| LoadInst *LI = cast<LoadInst>(I); |
| |
| const Type *LoadedTy = PT->getElementType(); |
| |
| // They could be loading the first element of a composite type... |
| if (const CompositeType *CT = dyn_cast<CompositeType>(LoadedTy)) { |
| unsigned Offset = 0; // No offset, get first leaf. |
| std::vector<Value*> Indices; // Discarded... |
| LoadedTy = getStructOffsetType(CT, Offset, Indices, TD, false); |
| assert(Offset == 0 && "Offset changed from zero???"); |
| } |
| |
| if (!LoadedTy->isFirstClassType()) |
| return false; |
| |
| if (TD.getTypeSize(LoadedTy) != TD.getTypeSize(LI->getType())) |
| return false; |
| |
| return ValueConvertibleToType(LI, LoadedTy, CTMap, TD); |
| } |
| return false; |
| |
| case Instruction::Store: { |
| StoreInst *SI = cast<StoreInst>(I); |
| |
| if (V == I->getOperand(0)) { |
| ValueTypeCache::iterator CTMI = CTMap.find(I->getOperand(1)); |
| if (CTMI != CTMap.end()) { // Operand #1 is in the table already? |
| // If so, check to see if it's Ty*, or, more importantly, if it is a |
| // pointer to a structure where the first element is a Ty... this code |
| // is necessary because we might be trying to change the source and |
| // destination type of the store (they might be related) and the dest |
| // pointer type might be a pointer to structure. Below we allow pointer |
| // to structures where the 0th element is compatible with the value, |
| // now we have to support the symmetrical part of this. |
| // |
| const Type *ElTy = cast<PointerType>(CTMI->second)->getElementType(); |
| |
| // Already a pointer to what we want? Trivially accept... |
| if (ElTy == Ty) return true; |
| |
| // Tricky case now, if the destination is a pointer to structure, |
| // obviously the source is not allowed to be a structure (cannot copy |
| // a whole structure at a time), so the level raiser must be trying to |
| // store into the first field. Check for this and allow it now: |
| // |
| if (const StructType *SElTy = dyn_cast<StructType>(ElTy)) { |
| unsigned Offset = 0; |
| std::vector<Value*> Indices; |
| ElTy = getStructOffsetType(ElTy, Offset, Indices, TD, false); |
| assert(Offset == 0 && "Offset changed!"); |
| if (ElTy == 0) // Element at offset zero in struct doesn't exist! |
| return false; // Can only happen for {}* |
| |
| if (ElTy == Ty) // Looks like the 0th element of structure is |
| return true; // compatible! Accept now! |
| |
| // Otherwise we know that we can't work, so just stop trying now. |
| return false; |
| } |
| } |
| |
| // Can convert the store if we can convert the pointer operand to match |
| // the new value type... |
| return ExpressionConvertibleToType(I->getOperand(1), PointerType::get(Ty), |
| CTMap, TD); |
| } else if (const PointerType *PT = dyn_cast<PointerType>(Ty)) { |
| const Type *ElTy = PT->getElementType(); |
| assert(V == I->getOperand(1)); |
| |
| if (isa<StructType>(ElTy)) { |
| // We can change the destination pointer if we can store our first |
| // argument into the first element of the structure... |
| // |
| unsigned Offset = 0; |
| std::vector<Value*> Indices; |
| ElTy = getStructOffsetType(ElTy, Offset, Indices, TD, false); |
| assert(Offset == 0 && "Offset changed!"); |
| if (ElTy == 0) // Element at offset zero in struct doesn't exist! |
| return false; // Can only happen for {}* |
| } |
| |
| // Must move the same amount of data... |
| if (!ElTy->isSized() || |
| TD.getTypeSize(ElTy) != TD.getTypeSize(I->getOperand(0)->getType())) |
| return false; |
| |
| // Can convert store if the incoming value is convertible and if the |
| // result will preserve semantics... |
| const Type *Op0Ty = I->getOperand(0)->getType(); |
| if (!(Op0Ty->isIntegral() ^ ElTy->isIntegral()) && |
| !(Op0Ty->isFloatingPoint() ^ ElTy->isFloatingPoint())) |
| return ExpressionConvertibleToType(I->getOperand(0), ElTy, CTMap, TD); |
| } |
| return false; |
| } |
| |
| case Instruction::PHI: { |
| PHINode *PN = cast<PHINode>(I); |
| // Be conservative if we find a giant PHI node. |
| if (PN->getNumIncomingValues() > 32) return false; |
| |
| for (unsigned i = 0; i < PN->getNumIncomingValues(); ++i) |
| if (!ExpressionConvertibleToType(PN->getIncomingValue(i), Ty, CTMap, TD)) |
| return false; |
| return ValueConvertibleToType(PN, Ty, CTMap, TD); |
| } |
| |
| case Instruction::Call: { |
| User::op_iterator OI = std::find(I->op_begin(), I->op_end(), V); |
| assert (OI != I->op_end() && "Not using value!"); |
| unsigned OpNum = OI - I->op_begin(); |
| |
| // Are we trying to change the function pointer value to a new type? |
| if (OpNum == 0) { |
| const PointerType *PTy = dyn_cast<PointerType>(Ty); |
| if (PTy == 0) return false; // Can't convert to a non-pointer type... |
| const FunctionType *FTy = dyn_cast<FunctionType>(PTy->getElementType()); |
| if (FTy == 0) return false; // Can't convert to a non ptr to function... |
| |
| // Do not allow converting to a call where all of the operands are ...'s |
| if (FTy->getNumParams() == 0 && FTy->isVarArg()) |
| return false; // Do not permit this conversion! |
| |
| // Perform sanity checks to make sure that new function type has the |
| // correct number of arguments... |
| // |
| unsigned NumArgs = I->getNumOperands()-1; // Don't include function ptr |
| |
| // Cannot convert to a type that requires more fixed arguments than |
| // the call provides... |
| // |
| if (NumArgs < FTy->getNumParams()) return false; |
| |
| // Unless this is a vararg function type, we cannot provide more arguments |
| // than are desired... |
| // |
| if (!FTy->isVarArg() && NumArgs > FTy->getNumParams()) |
| return false; |
| |
| // Okay, at this point, we know that the call and the function type match |
| // number of arguments. Now we see if we can convert the arguments |
| // themselves. Note that we do not require operands to be convertible, |
| // we can insert casts if they are convertible but not compatible. The |
| // reason for this is that we prefer to have resolved functions but casted |
| // arguments if possible. |
| // |
| for (unsigned i = 0, NA = FTy->getNumParams(); i < NA; ++i) |
| if (!FTy->getParamType(i)->isLosslesslyConvertibleTo(I->getOperand(i+1)->getType())) |
| return false; // Operands must have compatible types! |
| |
| // Okay, at this point, we know that all of the arguments can be |
| // converted. We succeed if we can change the return type if |
| // necessary... |
| // |
| return ValueConvertibleToType(I, FTy->getReturnType(), CTMap, TD); |
| } |
| |
| const PointerType *MPtr = cast<PointerType>(I->getOperand(0)->getType()); |
| const FunctionType *FTy = cast<FunctionType>(MPtr->getElementType()); |
| if (!FTy->isVarArg()) return false; |
| |
| if ((OpNum-1) < FTy->getNumParams()) |
| return false; // It's not in the varargs section... |
| |
| // If we get this far, we know the value is in the varargs section of the |
| // function! We can convert if we don't reinterpret the value... |
| // |
| return Ty->isLosslesslyConvertibleTo(V->getType()); |
| } |
| } |
| return false; |
| } |
| |
| |
| void llvm::ConvertValueToNewType(Value *V, Value *NewVal, ValueMapCache &VMC, |
| const TargetData &TD) { |
| ValueHandle VH(VMC, V); |
| |
| // FIXME: This is horrible! |
| unsigned NumUses = V->getNumUses(); |
| for (unsigned It = 0; It < NumUses; ) { |
| unsigned OldSize = NumUses; |
| Value::use_iterator UI = V->use_begin(); |
| std::advance(UI, It); |
| ConvertOperandToType(*UI, V, NewVal, VMC, TD); |
| NumUses = V->getNumUses(); |
| if (NumUses == OldSize) ++It; |
| } |
| } |
| |
| |
| |
| static void ConvertOperandToType(User *U, Value *OldVal, Value *NewVal, |
| ValueMapCache &VMC, const TargetData &TD) { |
| if (isa<ValueHandle>(U)) return; // Valuehandles don't let go of operands... |
| |
| if (VMC.OperandsMapped.count(U)) return; |
| VMC.OperandsMapped.insert(U); |
| |
| ValueMapCache::ExprMapTy::iterator VMCI = VMC.ExprMap.find(U); |
| if (VMCI != VMC.ExprMap.end()) |
| return; |
| |
| |
| Instruction *I = cast<Instruction>(U); // Only Instructions convertible |
| |
| BasicBlock *BB = I->getParent(); |
| assert(BB != 0 && "Instruction not embedded in basic block!"); |
| std::string Name = I->getName(); |
| I->setName(""); |
| Instruction *Res; // Result of conversion |
| |
| //std::cerr << endl << endl << "Type:\t" << Ty << "\nInst: " << I |
| // << "BB Before: " << BB << endl; |
| |
| // Prevent I from being removed... |
| ValueHandle IHandle(VMC, I); |
| |
| const Type *NewTy = NewVal->getType(); |
| Constant *Dummy = (NewTy != Type::VoidTy) ? |
| Constant::getNullValue(NewTy) : 0; |
| |
| switch (I->getOpcode()) { |
| case Instruction::Cast: |
| if (VMC.NewCasts.count(ValueHandle(VMC, I))) { |
| // This cast has already had it's value converted, causing a new cast to |
| // be created. We don't want to create YET ANOTHER cast instruction |
| // representing the original one, so just modify the operand of this cast |
| // instruction, which we know is newly created. |
| I->setOperand(0, NewVal); |
| I->setName(Name); // give I its name back |
| return; |
| |
| } else { |
| Res = new CastInst(NewVal, I->getType(), Name); |
| } |
| break; |
| |
| case Instruction::Add: |
| case Instruction::Sub: |
| case Instruction::SetEQ: |
| case Instruction::SetNE: { |
| Res = BinaryOperator::create(cast<BinaryOperator>(I)->getOpcode(), |
| Dummy, Dummy, Name); |
| VMC.ExprMap[I] = Res; // Add node to expression eagerly |
| |
| unsigned OtherIdx = (OldVal == I->getOperand(0)) ? 1 : 0; |
| Value *OtherOp = I->getOperand(OtherIdx); |
| Res->setOperand(!OtherIdx, NewVal); |
| Value *NewOther = ConvertExpressionToType(OtherOp, NewTy, VMC, TD); |
| Res->setOperand(OtherIdx, NewOther); |
| break; |
| } |
| case Instruction::Shl: |
| case Instruction::Shr: |
| assert(I->getOperand(0) == OldVal); |
| Res = new ShiftInst(cast<ShiftInst>(I)->getOpcode(), NewVal, |
| I->getOperand(1), Name); |
| break; |
| |
| case Instruction::Free: // Free can free any pointer type! |
| assert(I->getOperand(0) == OldVal); |
| Res = new FreeInst(NewVal); |
| break; |
| |
| |
| case Instruction::Load: { |
| assert(I->getOperand(0) == OldVal && isa<PointerType>(NewVal->getType())); |
| const Type *LoadedTy = |
| cast<PointerType>(NewVal->getType())->getElementType(); |
| |
| Value *Src = NewVal; |
| |
| if (const CompositeType *CT = dyn_cast<CompositeType>(LoadedTy)) { |
| std::vector<Value*> Indices; |
| Indices.push_back(Constant::getNullValue(Type::UIntTy)); |
| |
| unsigned Offset = 0; // No offset, get first leaf. |
| LoadedTy = getStructOffsetType(CT, Offset, Indices, TD, false); |
| assert(LoadedTy->isFirstClassType()); |
| |
| if (Indices.size() != 1) { // Do not generate load X, 0 |
| // Insert the GEP instruction before this load. |
| Src = new GetElementPtrInst(Src, Indices, Name+".idx", I); |
| } |
| } |
| |
| Res = new LoadInst(Src, Name); |
| assert(Res->getType()->isFirstClassType() && "Load of structure or array!"); |
| break; |
| } |
| |
| case Instruction::Store: { |
| if (I->getOperand(0) == OldVal) { // Replace the source value |
| // Check to see if operand #1 has already been converted... |
| ValueMapCache::ExprMapTy::iterator VMCI = |
| VMC.ExprMap.find(I->getOperand(1)); |
| if (VMCI != VMC.ExprMap.end()) { |
| // Comments describing this stuff are in the OperandConvertibleToType |
| // switch statement for Store... |
| // |
| const Type *ElTy = |
| cast<PointerType>(VMCI->second->getType())->getElementType(); |
| |
| Value *SrcPtr = VMCI->second; |
| |
| if (ElTy != NewTy) { |
| // We check that this is a struct in the initial scan... |
| const StructType *SElTy = cast<StructType>(ElTy); |
| |
| std::vector<Value*> Indices; |
| Indices.push_back(Constant::getNullValue(Type::UIntTy)); |
| |
| unsigned Offset = 0; |
| const Type *Ty = getStructOffsetType(ElTy, Offset, Indices, TD,false); |
| assert(Offset == 0 && "Offset changed!"); |
| assert(NewTy == Ty && "Did not convert to correct type!"); |
| |
| // Insert the GEP instruction before this store. |
| SrcPtr = new GetElementPtrInst(SrcPtr, Indices, |
| SrcPtr->getName()+".idx", I); |
| } |
| Res = new StoreInst(NewVal, SrcPtr); |
| |
| VMC.ExprMap[I] = Res; |
| } else { |
| // Otherwise, we haven't converted Operand #1 over yet... |
| const PointerType *NewPT = PointerType::get(NewTy); |
| Res = new StoreInst(NewVal, Constant::getNullValue(NewPT)); |
| VMC.ExprMap[I] = Res; |
| Res->setOperand(1, ConvertExpressionToType(I->getOperand(1), |
| NewPT, VMC, TD)); |
| } |
| } else { // Replace the source pointer |
| const Type *ValTy = cast<PointerType>(NewTy)->getElementType(); |
| |
| Value *SrcPtr = NewVal; |
| |
| if (isa<StructType>(ValTy)) { |
| std::vector<Value*> Indices; |
| Indices.push_back(Constant::getNullValue(Type::UIntTy)); |
| |
| unsigned Offset = 0; |
| ValTy = getStructOffsetType(ValTy, Offset, Indices, TD, false); |
| |
| assert(Offset == 0 && ValTy); |
| |
| // Insert the GEP instruction before this store. |
| SrcPtr = new GetElementPtrInst(SrcPtr, Indices, |
| SrcPtr->getName()+".idx", I); |
| } |
| |
| Res = new StoreInst(Constant::getNullValue(ValTy), SrcPtr); |
| VMC.ExprMap[I] = Res; |
| Res->setOperand(0, ConvertExpressionToType(I->getOperand(0), |
| ValTy, VMC, TD)); |
| } |
| break; |
| } |
| |
| case Instruction::PHI: { |
| PHINode *OldPN = cast<PHINode>(I); |
| PHINode *NewPN = new PHINode(NewTy, Name); |
| VMC.ExprMap[I] = NewPN; |
| |
| while (OldPN->getNumOperands()) { |
| BasicBlock *BB = OldPN->getIncomingBlock(0); |
| Value *OldVal = OldPN->getIncomingValue(0); |
| ValueHandle OldValHandle(VMC, OldVal); |
| OldPN->removeIncomingValue(BB, false); |
| Value *V = ConvertExpressionToType(OldVal, NewTy, VMC, TD); |
| NewPN->addIncoming(V, BB); |
| } |
| Res = NewPN; |
| break; |
| } |
| |
| case Instruction::Call: { |
| Value *Meth = I->getOperand(0); |
| std::vector<Value*> Params(I->op_begin()+1, I->op_end()); |
| |
| if (Meth == OldVal) { // Changing the function pointer? |
| const PointerType *NewPTy = cast<PointerType>(NewVal->getType()); |
| const FunctionType *NewTy = cast<FunctionType>(NewPTy->getElementType()); |
| |
| if (NewTy->getReturnType() == Type::VoidTy) |
| Name = ""; // Make sure not to name a void call! |
| |
| // Get an iterator to the call instruction so that we can insert casts for |
| // operands if need be. Note that we do not require operands to be |
| // convertible, we can insert casts if they are convertible but not |
| // compatible. The reason for this is that we prefer to have resolved |
| // functions but casted arguments if possible. |
| // |
| BasicBlock::iterator It = I; |
| |
| // Convert over all of the call operands to their new types... but only |
| // convert over the part that is not in the vararg section of the call. |
| // |
| for (unsigned i = 0; i != NewTy->getNumParams(); ++i) |
| if (Params[i]->getType() != NewTy->getParamType(i)) { |
| // Create a cast to convert it to the right type, we know that this |
| // is a lossless cast... |
| // |
| Params[i] = new CastInst(Params[i], NewTy->getParamType(i), |
| "callarg.cast." + |
| Params[i]->getName(), It); |
| } |
| Meth = NewVal; // Update call destination to new value |
| |
| } else { // Changing an argument, must be in vararg area |
| std::vector<Value*>::iterator OI = |
| std::find(Params.begin(), Params.end(), OldVal); |
| assert (OI != Params.end() && "Not using value!"); |
| |
| *OI = NewVal; |
| } |
| |
| Res = new CallInst(Meth, Params, Name); |
| if (cast<CallInst>(I)->isTailCall()) |
| cast<CallInst>(Res)->setTailCall(); |
| cast<CallInst>(Res)->setCallingConv(cast<CallInst>(I)->getCallingConv()); |
| break; |
| } |
| default: |
| assert(0 && "Expression convertible, but don't know how to convert?"); |
| return; |
| } |
| |
| // If the instruction was newly created, insert it into the instruction |
| // stream. |
| // |
| BasicBlock::iterator It = I; |
| assert(It != BB->end() && "Instruction not in own basic block??"); |
| BB->getInstList().insert(It, Res); // Keep It pointing to old instruction |
| |
| DEBUG(std::cerr << "COT CREATED: " << (void*)Res << " " << *Res |
| << "In: " << (void*)I << " " << *I << "Out: " << (void*)Res |
| << " " << *Res); |
| |
| // Add the instruction to the expression map |
| VMC.ExprMap[I] = Res; |
| |
| if (I->getType() != Res->getType()) |
| ConvertValueToNewType(I, Res, VMC, TD); |
| else { |
| for (Value::use_iterator UI = I->use_begin(), E = I->use_end(); |
| UI != E; ) |
| if (isa<ValueHandle>(*UI)) { |
| ++UI; |
| } else { |
| Use &U = UI.getUse(); |
| ++UI; // Do not invalidate UI. |
| U.set(Res); |
| } |
| } |
| } |
| |
| |
| ValueHandle::ValueHandle(ValueMapCache &VMC, Value *V) |
| : Instruction(Type::VoidTy, UserOp1, &Op, 1, ""), Op(V, this), Cache(VMC) { |
| //DEBUG(std::cerr << "VH AQUIRING: " << (void*)V << " " << V); |
| } |
| |
| ValueHandle::ValueHandle(const ValueHandle &VH) |
| : Instruction(Type::VoidTy, UserOp1, &Op, 1, ""), |
| Op(VH.Op, this), Cache(VH.Cache) { |
| //DEBUG(std::cerr << "VH AQUIRING: " << (void*)V << " " << V); |
| } |
| |
| static void RecursiveDelete(ValueMapCache &Cache, Instruction *I) { |
| if (!I || !I->use_empty()) return; |
| |
| assert(I->getParent() && "Inst not in basic block!"); |
| |
| //DEBUG(std::cerr << "VH DELETING: " << (void*)I << " " << I); |
| |
| for (User::op_iterator OI = I->op_begin(), OE = I->op_end(); |
| OI != OE; ++OI) |
| if (Instruction *U = dyn_cast<Instruction>(OI)) { |
| *OI = 0; |
| RecursiveDelete(Cache, U); |
| } |
| |
| I->getParent()->getInstList().remove(I); |
| |
| Cache.OperandsMapped.erase(I); |
| Cache.ExprMap.erase(I); |
| delete I; |
| } |
| |
| ValueHandle::~ValueHandle() { |
| if (Op->hasOneUse()) { |
| Value *V = Op; |
| Op.set(0); // Drop use! |
| |
| // Now we just need to remove the old instruction so we don't get infinite |
| // loops. Note that we cannot use DCE because DCE won't remove a store |
| // instruction, for example. |
| // |
| RecursiveDelete(Cache, dyn_cast<Instruction>(V)); |
| } else { |
| //DEBUG(std::cerr << "VH RELEASING: " << (void*)Operands[0].get() << " " |
| // << Operands[0]->getNumUses() << " " << Operands[0]); |
| } |
| } |
| |
