1 //===- ExprTypeConvert.cpp - Code to change an LLVM Expr Type -------------===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by the LLVM research group and is distributed under
6 // the University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements the part of level raising that checks to see if it is
11 // possible to coerce an entire expression tree into a different type. If
12 // convertible, other routines from this file will do the conversion.
14 //===----------------------------------------------------------------------===//
16 #include "TransformInternals.h"
17 #include "llvm/Constants.h"
18 #include "llvm/Instructions.h"
19 #include "llvm/Analysis/Expressions.h"
20 #include "Support/STLExtras.h"
21 #include "Support/Debug.h"
25 static bool OperandConvertibleToType(User *U, Value *V, const Type *Ty,
26 ValueTypeCache &ConvertedTypes,
27 const TargetData &TD);
29 static void ConvertOperandToType(User *U, Value *OldVal, Value *NewVal,
30 ValueMapCache &VMC, const TargetData &TD);
32 // Peephole Malloc instructions: we take a look at the use chain of the
33 // malloc instruction, and try to find out if the following conditions hold:
34 // 1. The malloc is of the form: 'malloc [sbyte], uint <constant>'
35 // 2. The only users of the malloc are cast & add instructions
36 // 3. Of the cast instructions, there is only one destination pointer type
37 // [RTy] where the size of the pointed to object is equal to the number
38 // of bytes allocated.
40 // If these conditions hold, we convert the malloc to allocate an [RTy]
41 // element. TODO: This comment is out of date WRT arrays
43 static bool MallocConvertibleToType(MallocInst *MI, const Type *Ty,
44 ValueTypeCache &CTMap,
45 const TargetData &TD) {
46 if (!isa<PointerType>(Ty)) return false; // Malloc always returns pointers
48 // Deal with the type to allocate, not the pointer type...
49 Ty = cast<PointerType>(Ty)->getElementType();
50 if (!Ty->isSized()) return false; // Can only alloc something with a size
52 // Analyze the number of bytes allocated...
53 ExprType Expr = ClassifyExpr(MI->getArraySize());
55 // Get information about the base datatype being allocated, before & after
56 int ReqTypeSize = TD.getTypeSize(Ty);
57 if (ReqTypeSize == 0) return false;
58 unsigned OldTypeSize = TD.getTypeSize(MI->getType()->getElementType());
60 // Must have a scale or offset to analyze it...
61 if (!Expr.Offset && !Expr.Scale && OldTypeSize == 1) return false;
63 // Get the offset and scale of the allocation...
64 int64_t OffsetVal = Expr.Offset ? getConstantValue(Expr.Offset) : 0;
65 int64_t ScaleVal = Expr.Scale ? getConstantValue(Expr.Scale) :(Expr.Var != 0);
67 // The old type might not be of unit size, take old size into consideration
69 int64_t Offset = OffsetVal * OldTypeSize;
70 int64_t Scale = ScaleVal * OldTypeSize;
72 // In order to be successful, both the scale and the offset must be a multiple
73 // of the requested data type's size.
75 if (Offset/ReqTypeSize*ReqTypeSize != Offset ||
76 Scale/ReqTypeSize*ReqTypeSize != Scale)
77 return false; // Nope.
82 static Instruction *ConvertMallocToType(MallocInst *MI, const Type *Ty,
83 const std::string &Name,
85 const TargetData &TD){
86 BasicBlock *BB = MI->getParent();
87 BasicBlock::iterator It = BB->end();
89 // Analyze the number of bytes allocated...
90 ExprType Expr = ClassifyExpr(MI->getArraySize());
92 const PointerType *AllocTy = cast<PointerType>(Ty);
93 const Type *ElType = AllocTy->getElementType();
95 unsigned DataSize = TD.getTypeSize(ElType);
96 unsigned OldTypeSize = TD.getTypeSize(MI->getType()->getElementType());
98 // Get the offset and scale coefficients that we are allocating...
99 int64_t OffsetVal = (Expr.Offset ? getConstantValue(Expr.Offset) : 0);
100 int64_t ScaleVal = Expr.Scale ? getConstantValue(Expr.Scale) : (Expr.Var !=0);
102 // The old type might not be of unit size, take old size into consideration
104 unsigned Offset = (uint64_t)OffsetVal * OldTypeSize / DataSize;
105 unsigned Scale = (uint64_t)ScaleVal * OldTypeSize / DataSize;
107 // Locate the malloc instruction, because we may be inserting instructions
110 // If we have a scale, apply it first...
112 // Expr.Var is not necessarily unsigned right now, insert a cast now.
113 if (Expr.Var->getType() != Type::UIntTy)
114 Expr.Var = new CastInst(Expr.Var, Type::UIntTy,
115 Expr.Var->getName()+"-uint", It);
118 Expr.Var = BinaryOperator::create(Instruction::Mul, Expr.Var,
119 ConstantUInt::get(Type::UIntTy, Scale),
120 Expr.Var->getName()+"-scl", It);
123 // If we are not scaling anything, just make the offset be the "var"...
124 Expr.Var = ConstantUInt::get(Type::UIntTy, Offset);
125 Offset = 0; Scale = 1;
128 // If we have an offset now, add it in...
130 assert(Expr.Var && "Var must be nonnull by now!");
131 Expr.Var = BinaryOperator::create(Instruction::Add, Expr.Var,
132 ConstantUInt::get(Type::UIntTy, Offset),
133 Expr.Var->getName()+"-off", It);
136 assert(AllocTy == Ty);
137 return new MallocInst(AllocTy->getElementType(), Expr.Var, Name);
141 // ExpressionConvertibleToType - Return true if it is possible
142 bool llvm::ExpressionConvertibleToType(Value *V, const Type *Ty,
143 ValueTypeCache &CTMap, const TargetData &TD) {
144 // Expression type must be holdable in a register.
145 if (!Ty->isFirstClassType())
148 ValueTypeCache::iterator CTMI = CTMap.find(V);
149 if (CTMI != CTMap.end()) return CTMI->second == Ty;
151 // If it's a constant... all constants can be converted to a different
154 if (Constant *CPV = dyn_cast<Constant>(V))
158 if (V->getType() == Ty) return true; // Expression already correct type!
160 Instruction *I = dyn_cast<Instruction>(V);
161 if (I == 0) return false; // Otherwise, we can't convert!
163 switch (I->getOpcode()) {
164 case Instruction::Cast:
165 // We can convert the expr if the cast destination type is losslessly
166 // convertible to the requested type.
167 if (!Ty->isLosslesslyConvertibleTo(I->getType())) return false;
169 // We also do not allow conversion of a cast that casts from a ptr to array
170 // of X to a *X. For example: cast [4 x %List *] * %val to %List * *
172 if (const PointerType *SPT =
173 dyn_cast<PointerType>(I->getOperand(0)->getType()))
174 if (const PointerType *DPT = dyn_cast<PointerType>(I->getType()))
175 if (const ArrayType *AT = dyn_cast<ArrayType>(SPT->getElementType()))
176 if (AT->getElementType() == DPT->getElementType())
180 case Instruction::Add:
181 case Instruction::Sub:
182 if (!Ty->isInteger() && !Ty->isFloatingPoint()) return false;
183 if (!ExpressionConvertibleToType(I->getOperand(0), Ty, CTMap, TD) ||
184 !ExpressionConvertibleToType(I->getOperand(1), Ty, CTMap, TD))
187 case Instruction::Shr:
188 if (!Ty->isInteger()) return false;
189 if (Ty->isSigned() != V->getType()->isSigned()) return false;
191 case Instruction::Shl:
192 if (!Ty->isInteger()) return false;
193 if (!ExpressionConvertibleToType(I->getOperand(0), Ty, CTMap, TD))
197 case Instruction::Load: {
198 LoadInst *LI = cast<LoadInst>(I);
199 if (!ExpressionConvertibleToType(LI->getPointerOperand(),
200 PointerType::get(Ty), CTMap, TD))
204 case Instruction::PHI: {
205 PHINode *PN = cast<PHINode>(I);
206 // Be conservative if we find a giant PHI node.
207 if (PN->getNumIncomingValues() > 32) return false;
209 for (unsigned i = 0; i < PN->getNumIncomingValues(); ++i)
210 if (!ExpressionConvertibleToType(PN->getIncomingValue(i), Ty, CTMap, TD))
215 case Instruction::Malloc:
216 if (!MallocConvertibleToType(cast<MallocInst>(I), Ty, CTMap, TD))
220 case Instruction::GetElementPtr: {
221 // GetElementPtr's are directly convertible to a pointer type if they have
222 // a number of zeros at the end. Because removing these values does not
223 // change the logical offset of the GEP, it is okay and fair to remove them.
224 // This can change this:
225 // %t1 = getelementptr %Hosp * %hosp, ubyte 4, ubyte 0 ; <%List **>
226 // %t2 = cast %List * * %t1 to %List *
228 // %t2 = getelementptr %Hosp * %hosp, ubyte 4 ; <%List *>
230 GetElementPtrInst *GEP = cast<GetElementPtrInst>(I);
231 const PointerType *PTy = dyn_cast<PointerType>(Ty);
232 if (!PTy) return false; // GEP must always return a pointer...
233 const Type *PVTy = PTy->getElementType();
235 // Check to see if there are zero elements that we can remove from the
236 // index array. If there are, check to see if removing them causes us to
237 // get to the right type...
239 std::vector<Value*> Indices(GEP->idx_begin(), GEP->idx_end());
240 const Type *BaseType = GEP->getPointerOperand()->getType();
241 const Type *ElTy = 0;
243 while (!Indices.empty() &&
244 Indices.back() == Constant::getNullValue(Indices.back()->getType())){
246 ElTy = GetElementPtrInst::getIndexedType(BaseType, Indices, true);
248 break; // Found a match!!
252 if (ElTy) break; // Found a number of zeros we can strip off!
254 // Otherwise, we can convert a GEP from one form to the other iff the
255 // current gep is of the form 'getelementptr sbyte*, long N
256 // and we could convert this to an appropriate GEP for the new type.
258 if (GEP->getNumOperands() == 2 &&
259 GEP->getType() == PointerType::get(Type::SByteTy)) {
261 // Do not Check to see if our incoming pointer can be converted
262 // to be a ptr to an array of the right type... because in more cases than
263 // not, it is simply not analyzable because of pointer/array
264 // discrepancies. To fix this, we will insert a cast before the GEP.
267 // Check to see if 'N' is an expression that can be converted to
268 // the appropriate size... if so, allow it.
270 std::vector<Value*> Indices;
271 const Type *ElTy = ConvertibleToGEP(PTy, I->getOperand(1), Indices, TD);
273 if (!ExpressionConvertibleToType(I->getOperand(0),
274 PointerType::get(ElTy), CTMap, TD))
275 return false; // Can't continue, ExConToTy might have polluted set!
280 // Otherwise, it could be that we have something like this:
281 // getelementptr [[sbyte] *] * %reg115, long %reg138 ; [sbyte]**
282 // and want to convert it into something like this:
283 // getelemenptr [[int] *] * %reg115, long %reg138 ; [int]**
285 if (GEP->getNumOperands() == 2 &&
286 PTy->getElementType()->isSized() &&
287 TD.getTypeSize(PTy->getElementType()) ==
288 TD.getTypeSize(GEP->getType()->getElementType())) {
289 const PointerType *NewSrcTy = PointerType::get(PVTy);
290 if (!ExpressionConvertibleToType(I->getOperand(0), NewSrcTy, CTMap, TD))
295 return false; // No match, maybe next time.
298 case Instruction::Call: {
299 if (isa<Function>(I->getOperand(0)))
300 return false; // Don't even try to change direct calls.
302 // If this is a function pointer, we can convert the return type if we can
303 // convert the source function pointer.
305 const PointerType *PT = cast<PointerType>(I->getOperand(0)->getType());
306 const FunctionType *FT = cast<FunctionType>(PT->getElementType());
307 std::vector<const Type *> ArgTys(FT->param_begin(), FT->param_end());
308 const FunctionType *NewTy =
309 FunctionType::get(Ty, ArgTys, FT->isVarArg());
310 if (!ExpressionConvertibleToType(I->getOperand(0),
311 PointerType::get(NewTy), CTMap, TD))
319 // Expressions are only convertible if all of the users of the expression can
320 // have this value converted. This makes use of the map to avoid infinite
323 for (Value::use_iterator It = I->use_begin(), E = I->use_end(); It != E; ++It)
324 if (!OperandConvertibleToType(*It, I, Ty, CTMap, TD))
331 Value *llvm::ConvertExpressionToType(Value *V, const Type *Ty,
332 ValueMapCache &VMC, const TargetData &TD) {
333 if (V->getType() == Ty) return V; // Already where we need to be?
335 ValueMapCache::ExprMapTy::iterator VMCI = VMC.ExprMap.find(V);
336 if (VMCI != VMC.ExprMap.end()) {
337 const Value *GV = VMCI->second;
338 const Type *GTy = VMCI->second->getType();
339 assert(VMCI->second->getType() == Ty);
341 if (Instruction *I = dyn_cast<Instruction>(V))
342 ValueHandle IHandle(VMC, I); // Remove I if it is unused now!
347 DEBUG(std::cerr << "CETT: " << (void*)V << " " << *V);
349 Instruction *I = dyn_cast<Instruction>(V);
351 Constant *CPV = cast<Constant>(V);
352 // Constants are converted by constant folding the cast that is required.
353 // We assume here that all casts are implemented for constant prop.
354 Value *Result = ConstantExpr::getCast(CPV, Ty);
355 // Add the instruction to the expression map
356 //VMC.ExprMap[V] = Result;
361 BasicBlock *BB = I->getParent();
362 std::string Name = I->getName(); if (!Name.empty()) I->setName("");
363 Instruction *Res; // Result of conversion
365 ValueHandle IHandle(VMC, I); // Prevent I from being removed!
367 Constant *Dummy = Constant::getNullValue(Ty);
369 switch (I->getOpcode()) {
370 case Instruction::Cast:
371 assert(VMC.NewCasts.count(ValueHandle(VMC, I)) == 0);
372 Res = new CastInst(I->getOperand(0), Ty, Name);
373 VMC.NewCasts.insert(ValueHandle(VMC, Res));
376 case Instruction::Add:
377 case Instruction::Sub:
378 Res = BinaryOperator::create(cast<BinaryOperator>(I)->getOpcode(),
380 VMC.ExprMap[I] = Res; // Add node to expression eagerly
382 Res->setOperand(0, ConvertExpressionToType(I->getOperand(0), Ty, VMC, TD));
383 Res->setOperand(1, ConvertExpressionToType(I->getOperand(1), Ty, VMC, TD));
386 case Instruction::Shl:
387 case Instruction::Shr:
388 Res = new ShiftInst(cast<ShiftInst>(I)->getOpcode(), Dummy,
389 I->getOperand(1), Name);
390 VMC.ExprMap[I] = Res;
391 Res->setOperand(0, ConvertExpressionToType(I->getOperand(0), Ty, VMC, TD));
394 case Instruction::Load: {
395 LoadInst *LI = cast<LoadInst>(I);
397 Res = new LoadInst(Constant::getNullValue(PointerType::get(Ty)), Name);
398 VMC.ExprMap[I] = Res;
399 Res->setOperand(0, ConvertExpressionToType(LI->getPointerOperand(),
400 PointerType::get(Ty), VMC, TD));
401 assert(Res->getOperand(0)->getType() == PointerType::get(Ty));
402 assert(Ty == Res->getType());
403 assert(Res->getType()->isFirstClassType() && "Load of structure or array!");
407 case Instruction::PHI: {
408 PHINode *OldPN = cast<PHINode>(I);
409 PHINode *NewPN = new PHINode(Ty, Name);
411 VMC.ExprMap[I] = NewPN; // Add node to expression eagerly
412 while (OldPN->getNumOperands()) {
413 BasicBlock *BB = OldPN->getIncomingBlock(0);
414 Value *OldVal = OldPN->getIncomingValue(0);
415 ValueHandle OldValHandle(VMC, OldVal);
416 OldPN->removeIncomingValue(BB, false);
417 Value *V = ConvertExpressionToType(OldVal, Ty, VMC, TD);
418 NewPN->addIncoming(V, BB);
424 case Instruction::Malloc: {
425 Res = ConvertMallocToType(cast<MallocInst>(I), Ty, Name, VMC, TD);
429 case Instruction::GetElementPtr: {
430 // GetElementPtr's are directly convertible to a pointer type if they have
431 // a number of zeros at the end. Because removing these values does not
432 // change the logical offset of the GEP, it is okay and fair to remove them.
433 // This can change this:
434 // %t1 = getelementptr %Hosp * %hosp, ubyte 4, ubyte 0 ; <%List **>
435 // %t2 = cast %List * * %t1 to %List *
437 // %t2 = getelementptr %Hosp * %hosp, ubyte 4 ; <%List *>
439 GetElementPtrInst *GEP = cast<GetElementPtrInst>(I);
441 // Check to see if there are zero elements that we can remove from the
442 // index array. If there are, check to see if removing them causes us to
443 // get to the right type...
445 std::vector<Value*> Indices(GEP->idx_begin(), GEP->idx_end());
446 const Type *BaseType = GEP->getPointerOperand()->getType();
447 const Type *PVTy = cast<PointerType>(Ty)->getElementType();
449 while (!Indices.empty() &&
450 Indices.back() == Constant::getNullValue(Indices.back()->getType())){
452 if (GetElementPtrInst::getIndexedType(BaseType, Indices, true) == PVTy) {
453 if (Indices.size() == 0)
454 Res = new CastInst(GEP->getPointerOperand(), BaseType); // NOOP CAST
456 Res = new GetElementPtrInst(GEP->getPointerOperand(), Indices, Name);
461 if (Res == 0 && GEP->getNumOperands() == 2 &&
462 GEP->getType() == PointerType::get(Type::SByteTy)) {
464 // Otherwise, we can convert a GEP from one form to the other iff the
465 // current gep is of the form 'getelementptr sbyte*, unsigned N
466 // and we could convert this to an appropriate GEP for the new type.
468 const PointerType *NewSrcTy = PointerType::get(PVTy);
469 BasicBlock::iterator It = I;
471 // Check to see if 'N' is an expression that can be converted to
472 // the appropriate size... if so, allow it.
474 std::vector<Value*> Indices;
475 const Type *ElTy = ConvertibleToGEP(NewSrcTy, I->getOperand(1),
478 assert(ElTy == PVTy && "Internal error, setup wrong!");
479 Res = new GetElementPtrInst(Constant::getNullValue(NewSrcTy),
481 VMC.ExprMap[I] = Res;
482 Res->setOperand(0, ConvertExpressionToType(I->getOperand(0),
487 // Otherwise, it could be that we have something like this:
488 // getelementptr [[sbyte] *] * %reg115, uint %reg138 ; [sbyte]**
489 // and want to convert it into something like this:
490 // getelemenptr [[int] *] * %reg115, uint %reg138 ; [int]**
493 const PointerType *NewSrcTy = PointerType::get(PVTy);
494 std::vector<Value*> Indices(GEP->idx_begin(), GEP->idx_end());
495 Res = new GetElementPtrInst(Constant::getNullValue(NewSrcTy),
497 VMC.ExprMap[I] = Res;
498 Res->setOperand(0, ConvertExpressionToType(I->getOperand(0),
503 assert(Res && "Didn't find match!");
507 case Instruction::Call: {
508 assert(!isa<Function>(I->getOperand(0)));
510 // If this is a function pointer, we can convert the return type if we can
511 // convert the source function pointer.
513 const PointerType *PT = cast<PointerType>(I->getOperand(0)->getType());
514 const FunctionType *FT = cast<FunctionType>(PT->getElementType());
515 std::vector<const Type *> ArgTys(FT->param_begin(), FT->param_end());
516 const FunctionType *NewTy =
517 FunctionType::get(Ty, ArgTys, FT->isVarArg());
518 const PointerType *NewPTy = PointerType::get(NewTy);
519 if (Ty == Type::VoidTy)
520 Name = ""; // Make sure not to name calls that now return void!
522 Res = new CallInst(Constant::getNullValue(NewPTy),
523 std::vector<Value*>(I->op_begin()+1, I->op_end()),
525 VMC.ExprMap[I] = Res;
526 Res->setOperand(0, ConvertExpressionToType(I->getOperand(0),NewPTy,VMC,TD));
530 assert(0 && "Expression convertible, but don't know how to convert?");
534 assert(Res->getType() == Ty && "Didn't convert expr to correct type!");
536 BB->getInstList().insert(I, Res);
538 // Add the instruction to the expression map
539 VMC.ExprMap[I] = Res;
542 unsigned NumUses = I->use_size();
543 for (unsigned It = 0; It < NumUses; ) {
544 unsigned OldSize = NumUses;
545 Value::use_iterator UI = I->use_begin();
546 std::advance(UI, It);
547 ConvertOperandToType(*UI, I, Res, VMC, TD);
548 NumUses = I->use_size();
549 if (NumUses == OldSize) ++It;
552 DEBUG(std::cerr << "ExpIn: " << (void*)I << " " << *I
553 << "ExpOut: " << (void*)Res << " " << *Res);
560 // ValueConvertibleToType - Return true if it is possible
561 bool llvm::ValueConvertibleToType(Value *V, const Type *Ty,
562 ValueTypeCache &ConvertedTypes,
563 const TargetData &TD) {
564 ValueTypeCache::iterator I = ConvertedTypes.find(V);
565 if (I != ConvertedTypes.end()) return I->second == Ty;
566 ConvertedTypes[V] = Ty;
568 // It is safe to convert the specified value to the specified type IFF all of
569 // the uses of the value can be converted to accept the new typed value.
571 if (V->getType() != Ty) {
572 for (Value::use_iterator I = V->use_begin(), E = V->use_end(); I != E; ++I)
573 if (!OperandConvertibleToType(*I, V, Ty, ConvertedTypes, TD))
584 // OperandConvertibleToType - Return true if it is possible to convert operand
585 // V of User (instruction) U to the specified type. This is true iff it is
586 // possible to change the specified instruction to accept this. CTMap is a map
587 // of converted types, so that circular definitions will see the future type of
588 // the expression, not the static current type.
590 static bool OperandConvertibleToType(User *U, Value *V, const Type *Ty,
591 ValueTypeCache &CTMap,
592 const TargetData &TD) {
593 // if (V->getType() == Ty) return true; // Operand already the right type?
595 // Expression type must be holdable in a register.
596 if (!Ty->isFirstClassType())
599 Instruction *I = dyn_cast<Instruction>(U);
600 if (I == 0) return false; // We can't convert!
602 switch (I->getOpcode()) {
603 case Instruction::Cast:
604 assert(I->getOperand(0) == V);
605 // We can convert the expr if the cast destination type is losslessly
606 // convertible to the requested type.
607 // Also, do not change a cast that is a noop cast. For all intents and
608 // purposes it should be eliminated.
609 if (!Ty->isLosslesslyConvertibleTo(I->getOperand(0)->getType()) ||
610 I->getType() == I->getOperand(0)->getType())
613 // Do not allow a 'cast ushort %V to uint' to have it's first operand be
614 // converted to a 'short' type. Doing so changes the way sign promotion
615 // happens, and breaks things. Only allow the cast to take place if the
616 // signedness doesn't change... or if the current cast is not a lossy
619 if (!I->getType()->isLosslesslyConvertibleTo(I->getOperand(0)->getType()) &&
620 I->getOperand(0)->getType()->isSigned() != Ty->isSigned())
623 // We also do not allow conversion of a cast that casts from a ptr to array
624 // of X to a *X. For example: cast [4 x %List *] * %val to %List * *
626 if (const PointerType *SPT =
627 dyn_cast<PointerType>(I->getOperand(0)->getType()))
628 if (const PointerType *DPT = dyn_cast<PointerType>(I->getType()))
629 if (const ArrayType *AT = dyn_cast<ArrayType>(SPT->getElementType()))
630 if (AT->getElementType() == DPT->getElementType())
634 case Instruction::Add:
635 if (isa<PointerType>(Ty)) {
636 Value *IndexVal = I->getOperand(V == I->getOperand(0) ? 1 : 0);
637 std::vector<Value*> Indices;
638 if (const Type *ETy = ConvertibleToGEP(Ty, IndexVal, Indices, TD)) {
639 const Type *RetTy = PointerType::get(ETy);
641 // Only successful if we can convert this type to the required type
642 if (ValueConvertibleToType(I, RetTy, CTMap, TD)) {
646 // We have to return failure here because ValueConvertibleToType could
647 // have polluted our map
652 case Instruction::Sub: {
653 if (!Ty->isInteger() && !Ty->isFloatingPoint()) return false;
655 Value *OtherOp = I->getOperand((V == I->getOperand(0)) ? 1 : 0);
656 return ValueConvertibleToType(I, Ty, CTMap, TD) &&
657 ExpressionConvertibleToType(OtherOp, Ty, CTMap, TD);
659 case Instruction::SetEQ:
660 case Instruction::SetNE: {
661 Value *OtherOp = I->getOperand((V == I->getOperand(0)) ? 1 : 0);
662 return ExpressionConvertibleToType(OtherOp, Ty, CTMap, TD);
664 case Instruction::Shr:
665 if (Ty->isSigned() != V->getType()->isSigned()) return false;
667 case Instruction::Shl:
668 if (I->getOperand(1) == V) return false; // Cannot change shift amount type
669 if (!Ty->isInteger()) return false;
670 return ValueConvertibleToType(I, Ty, CTMap, TD);
672 case Instruction::Free:
673 assert(I->getOperand(0) == V);
674 return isa<PointerType>(Ty); // Free can free any pointer type!
676 case Instruction::Load:
677 // Cannot convert the types of any subscripts...
678 if (I->getOperand(0) != V) return false;
680 if (const PointerType *PT = dyn_cast<PointerType>(Ty)) {
681 LoadInst *LI = cast<LoadInst>(I);
683 const Type *LoadedTy = PT->getElementType();
685 // They could be loading the first element of a composite type...
686 if (const CompositeType *CT = dyn_cast<CompositeType>(LoadedTy)) {
687 unsigned Offset = 0; // No offset, get first leaf.
688 std::vector<Value*> Indices; // Discarded...
689 LoadedTy = getStructOffsetType(CT, Offset, Indices, TD, false);
690 assert(Offset == 0 && "Offset changed from zero???");
693 if (!LoadedTy->isFirstClassType())
696 if (TD.getTypeSize(LoadedTy) != TD.getTypeSize(LI->getType()))
699 return ValueConvertibleToType(LI, LoadedTy, CTMap, TD);
703 case Instruction::Store: {
704 StoreInst *SI = cast<StoreInst>(I);
706 if (V == I->getOperand(0)) {
707 ValueTypeCache::iterator CTMI = CTMap.find(I->getOperand(1));
708 if (CTMI != CTMap.end()) { // Operand #1 is in the table already?
709 // If so, check to see if it's Ty*, or, more importantly, if it is a
710 // pointer to a structure where the first element is a Ty... this code
711 // is necessary because we might be trying to change the source and
712 // destination type of the store (they might be related) and the dest
713 // pointer type might be a pointer to structure. Below we allow pointer
714 // to structures where the 0th element is compatible with the value,
715 // now we have to support the symmetrical part of this.
717 const Type *ElTy = cast<PointerType>(CTMI->second)->getElementType();
719 // Already a pointer to what we want? Trivially accept...
720 if (ElTy == Ty) return true;
722 // Tricky case now, if the destination is a pointer to structure,
723 // obviously the source is not allowed to be a structure (cannot copy
724 // a whole structure at a time), so the level raiser must be trying to
725 // store into the first field. Check for this and allow it now:
727 if (const StructType *SElTy = dyn_cast<StructType>(ElTy)) {
729 std::vector<Value*> Indices;
730 ElTy = getStructOffsetType(ElTy, Offset, Indices, TD, false);
731 assert(Offset == 0 && "Offset changed!");
732 if (ElTy == 0) // Element at offset zero in struct doesn't exist!
733 return false; // Can only happen for {}*
735 if (ElTy == Ty) // Looks like the 0th element of structure is
736 return true; // compatible! Accept now!
738 // Otherwise we know that we can't work, so just stop trying now.
743 // Can convert the store if we can convert the pointer operand to match
744 // the new value type...
745 return ExpressionConvertibleToType(I->getOperand(1), PointerType::get(Ty),
747 } else if (const PointerType *PT = dyn_cast<PointerType>(Ty)) {
748 const Type *ElTy = PT->getElementType();
749 assert(V == I->getOperand(1));
751 if (isa<StructType>(ElTy)) {
752 // We can change the destination pointer if we can store our first
753 // argument into the first element of the structure...
756 std::vector<Value*> Indices;
757 ElTy = getStructOffsetType(ElTy, Offset, Indices, TD, false);
758 assert(Offset == 0 && "Offset changed!");
759 if (ElTy == 0) // Element at offset zero in struct doesn't exist!
760 return false; // Can only happen for {}*
763 // Must move the same amount of data...
764 if (!ElTy->isSized() ||
765 TD.getTypeSize(ElTy) != TD.getTypeSize(I->getOperand(0)->getType()))
768 // Can convert store if the incoming value is convertible and if the
769 // result will preserve semantics...
770 const Type *Op0Ty = I->getOperand(0)->getType();
771 if (!(Op0Ty->isIntegral() ^ ElTy->isIntegral()) &&
772 !(Op0Ty->isFloatingPoint() ^ ElTy->isFloatingPoint()))
773 return ExpressionConvertibleToType(I->getOperand(0), ElTy, CTMap, TD);
778 case Instruction::GetElementPtr:
779 if (V != I->getOperand(0) || !isa<PointerType>(Ty)) return false;
781 // If we have a two operand form of getelementptr, this is really little
782 // more than a simple addition. As with addition, check to see if the
783 // getelementptr instruction can be changed to index into the new type.
785 if (I->getNumOperands() == 2) {
786 const Type *OldElTy = cast<PointerType>(I->getType())->getElementType();
787 unsigned DataSize = TD.getTypeSize(OldElTy);
788 Value *Index = I->getOperand(1);
789 Instruction *TempScale = 0;
791 // If the old data element is not unit sized, we have to create a scale
792 // instruction so that ConvertibleToGEP will know the REAL amount we are
793 // indexing by. Note that this is never inserted into the instruction
794 // stream, so we have to delete it when we're done.
798 if (Index->getType()->isSigned())
799 CST = ConstantSInt::get(Index->getType(), DataSize);
801 CST = ConstantUInt::get(Index->getType(), DataSize);
803 TempScale = BinaryOperator::create(Instruction::Mul, Index, CST);
807 // Check to see if the second argument is an expression that can
808 // be converted to the appropriate size... if so, allow it.
810 std::vector<Value*> Indices;
811 const Type *ElTy = ConvertibleToGEP(Ty, Index, Indices, TD);
812 delete TempScale; // Free our temporary multiply if we made it
814 if (ElTy == 0) return false; // Cannot make conversion...
815 return ValueConvertibleToType(I, PointerType::get(ElTy), CTMap, TD);
819 case Instruction::PHI: {
820 PHINode *PN = cast<PHINode>(I);
821 // Be conservative if we find a giant PHI node.
822 if (PN->getNumIncomingValues() > 32) return false;
824 for (unsigned i = 0; i < PN->getNumIncomingValues(); ++i)
825 if (!ExpressionConvertibleToType(PN->getIncomingValue(i), Ty, CTMap, TD))
827 return ValueConvertibleToType(PN, Ty, CTMap, TD);
830 case Instruction::Call: {
831 User::op_iterator OI = find(I->op_begin(), I->op_end(), V);
832 assert (OI != I->op_end() && "Not using value!");
833 unsigned OpNum = OI - I->op_begin();
835 // Are we trying to change the function pointer value to a new type?
837 const PointerType *PTy = dyn_cast<PointerType>(Ty);
838 if (PTy == 0) return false; // Can't convert to a non-pointer type...
839 const FunctionType *FTy = dyn_cast<FunctionType>(PTy->getElementType());
840 if (FTy == 0) return false; // Can't convert to a non ptr to function...
842 // Do not allow converting to a call where all of the operands are ...'s
843 if (FTy->getNumParams() == 0 && FTy->isVarArg())
844 return false; // Do not permit this conversion!
846 // Perform sanity checks to make sure that new function type has the
847 // correct number of arguments...
849 unsigned NumArgs = I->getNumOperands()-1; // Don't include function ptr
851 // Cannot convert to a type that requires more fixed arguments than
852 // the call provides...
854 if (NumArgs < FTy->getNumParams()) return false;
856 // Unless this is a vararg function type, we cannot provide more arguments
857 // than are desired...
859 if (!FTy->isVarArg() && NumArgs > FTy->getNumParams())
862 // Okay, at this point, we know that the call and the function type match
863 // number of arguments. Now we see if we can convert the arguments
864 // themselves. Note that we do not require operands to be convertible,
865 // we can insert casts if they are convertible but not compatible. The
866 // reason for this is that we prefer to have resolved functions but casted
867 // arguments if possible.
869 for (unsigned i = 0, NA = FTy->getNumParams(); i < NA; ++i)
870 if (!FTy->getParamType(i)->isLosslesslyConvertibleTo(I->getOperand(i+1)->getType()))
871 return false; // Operands must have compatible types!
873 // Okay, at this point, we know that all of the arguments can be
874 // converted. We succeed if we can change the return type if
877 return ValueConvertibleToType(I, FTy->getReturnType(), CTMap, TD);
880 const PointerType *MPtr = cast<PointerType>(I->getOperand(0)->getType());
881 const FunctionType *FTy = cast<FunctionType>(MPtr->getElementType());
882 if (!FTy->isVarArg()) return false;
884 if ((OpNum-1) < FTy->getNumParams())
885 return false; // It's not in the varargs section...
887 // If we get this far, we know the value is in the varargs section of the
888 // function! We can convert if we don't reinterpret the value...
890 return Ty->isLosslesslyConvertibleTo(V->getType());
897 void llvm::ConvertValueToNewType(Value *V, Value *NewVal, ValueMapCache &VMC,
898 const TargetData &TD) {
899 ValueHandle VH(VMC, V);
901 unsigned NumUses = V->use_size();
902 for (unsigned It = 0; It < NumUses; ) {
903 unsigned OldSize = NumUses;
904 Value::use_iterator UI = V->use_begin();
905 std::advance(UI, It);
906 ConvertOperandToType(*UI, V, NewVal, VMC, TD);
907 NumUses = V->use_size();
908 if (NumUses == OldSize) ++It;
914 static void ConvertOperandToType(User *U, Value *OldVal, Value *NewVal,
915 ValueMapCache &VMC, const TargetData &TD) {
916 if (isa<ValueHandle>(U)) return; // Valuehandles don't let go of operands...
918 if (VMC.OperandsMapped.count(U)) return;
919 VMC.OperandsMapped.insert(U);
921 ValueMapCache::ExprMapTy::iterator VMCI = VMC.ExprMap.find(U);
922 if (VMCI != VMC.ExprMap.end())
926 Instruction *I = cast<Instruction>(U); // Only Instructions convertible
928 BasicBlock *BB = I->getParent();
929 assert(BB != 0 && "Instruction not embedded in basic block!");
930 std::string Name = I->getName();
932 Instruction *Res; // Result of conversion
934 //std::cerr << endl << endl << "Type:\t" << Ty << "\nInst: " << I
935 // << "BB Before: " << BB << endl;
937 // Prevent I from being removed...
938 ValueHandle IHandle(VMC, I);
940 const Type *NewTy = NewVal->getType();
941 Constant *Dummy = (NewTy != Type::VoidTy) ?
942 Constant::getNullValue(NewTy) : 0;
944 switch (I->getOpcode()) {
945 case Instruction::Cast:
946 if (VMC.NewCasts.count(ValueHandle(VMC, I))) {
947 // This cast has already had it's value converted, causing a new cast to
948 // be created. We don't want to create YET ANOTHER cast instruction
949 // representing the original one, so just modify the operand of this cast
950 // instruction, which we know is newly created.
951 I->setOperand(0, NewVal);
952 I->setName(Name); // give I its name back
956 Res = new CastInst(NewVal, I->getType(), Name);
960 case Instruction::Add:
961 if (isa<PointerType>(NewTy)) {
962 Value *IndexVal = I->getOperand(OldVal == I->getOperand(0) ? 1 : 0);
963 std::vector<Value*> Indices;
964 BasicBlock::iterator It = I;
966 if (const Type *ETy = ConvertibleToGEP(NewTy, IndexVal, Indices, TD,&It)){
967 // If successful, convert the add to a GEP
968 //const Type *RetTy = PointerType::get(ETy);
969 // First operand is actually the given pointer...
970 Res = new GetElementPtrInst(NewVal, Indices, Name);
971 assert(cast<PointerType>(Res->getType())->getElementType() == ETy &&
972 "ConvertibleToGEP broken!");
978 case Instruction::Sub:
979 case Instruction::SetEQ:
980 case Instruction::SetNE: {
981 Res = BinaryOperator::create(cast<BinaryOperator>(I)->getOpcode(),
983 VMC.ExprMap[I] = Res; // Add node to expression eagerly
985 unsigned OtherIdx = (OldVal == I->getOperand(0)) ? 1 : 0;
986 Value *OtherOp = I->getOperand(OtherIdx);
987 Value *NewOther = ConvertExpressionToType(OtherOp, NewTy, VMC, TD);
989 Res->setOperand(OtherIdx, NewOther);
990 Res->setOperand(!OtherIdx, NewVal);
993 case Instruction::Shl:
994 case Instruction::Shr:
995 assert(I->getOperand(0) == OldVal);
996 Res = new ShiftInst(cast<ShiftInst>(I)->getOpcode(), NewVal,
997 I->getOperand(1), Name);
1000 case Instruction::Free: // Free can free any pointer type!
1001 assert(I->getOperand(0) == OldVal);
1002 Res = new FreeInst(NewVal);
1006 case Instruction::Load: {
1007 assert(I->getOperand(0) == OldVal && isa<PointerType>(NewVal->getType()));
1008 const Type *LoadedTy =
1009 cast<PointerType>(NewVal->getType())->getElementType();
1011 Value *Src = NewVal;
1013 if (const CompositeType *CT = dyn_cast<CompositeType>(LoadedTy)) {
1014 std::vector<Value*> Indices;
1015 Indices.push_back(Constant::getNullValue(Type::UIntTy));
1017 unsigned Offset = 0; // No offset, get first leaf.
1018 LoadedTy = getStructOffsetType(CT, Offset, Indices, TD, false);
1019 assert(LoadedTy->isFirstClassType());
1021 if (Indices.size() != 1) { // Do not generate load X, 0
1022 // Insert the GEP instruction before this load.
1023 Src = new GetElementPtrInst(Src, Indices, Name+".idx", I);
1027 Res = new LoadInst(Src, Name);
1028 assert(Res->getType()->isFirstClassType() && "Load of structure or array!");
1032 case Instruction::Store: {
1033 if (I->getOperand(0) == OldVal) { // Replace the source value
1034 // Check to see if operand #1 has already been converted...
1035 ValueMapCache::ExprMapTy::iterator VMCI =
1036 VMC.ExprMap.find(I->getOperand(1));
1037 if (VMCI != VMC.ExprMap.end()) {
1038 // Comments describing this stuff are in the OperandConvertibleToType
1039 // switch statement for Store...
1042 cast<PointerType>(VMCI->second->getType())->getElementType();
1044 Value *SrcPtr = VMCI->second;
1046 if (ElTy != NewTy) {
1047 // We check that this is a struct in the initial scan...
1048 const StructType *SElTy = cast<StructType>(ElTy);
1050 std::vector<Value*> Indices;
1051 Indices.push_back(Constant::getNullValue(Type::UIntTy));
1053 unsigned Offset = 0;
1054 const Type *Ty = getStructOffsetType(ElTy, Offset, Indices, TD,false);
1055 assert(Offset == 0 && "Offset changed!");
1056 assert(NewTy == Ty && "Did not convert to correct type!");
1058 // Insert the GEP instruction before this store.
1059 SrcPtr = new GetElementPtrInst(SrcPtr, Indices,
1060 SrcPtr->getName()+".idx", I);
1062 Res = new StoreInst(NewVal, SrcPtr);
1064 VMC.ExprMap[I] = Res;
1066 // Otherwise, we haven't converted Operand #1 over yet...
1067 const PointerType *NewPT = PointerType::get(NewTy);
1068 Res = new StoreInst(NewVal, Constant::getNullValue(NewPT));
1069 VMC.ExprMap[I] = Res;
1070 Res->setOperand(1, ConvertExpressionToType(I->getOperand(1),
1073 } else { // Replace the source pointer
1074 const Type *ValTy = cast<PointerType>(NewTy)->getElementType();
1076 Value *SrcPtr = NewVal;
1078 if (isa<StructType>(ValTy)) {
1079 std::vector<Value*> Indices;
1080 Indices.push_back(Constant::getNullValue(Type::UIntTy));
1082 unsigned Offset = 0;
1083 ValTy = getStructOffsetType(ValTy, Offset, Indices, TD, false);
1085 assert(Offset == 0 && ValTy);
1087 // Insert the GEP instruction before this store.
1088 SrcPtr = new GetElementPtrInst(SrcPtr, Indices,
1089 SrcPtr->getName()+".idx", I);
1092 Res = new StoreInst(Constant::getNullValue(ValTy), SrcPtr);
1093 VMC.ExprMap[I] = Res;
1094 Res->setOperand(0, ConvertExpressionToType(I->getOperand(0),
1101 case Instruction::GetElementPtr: {
1102 // Convert a one index getelementptr into just about anything that is
1105 BasicBlock::iterator It = I;
1106 const Type *OldElTy = cast<PointerType>(I->getType())->getElementType();
1107 unsigned DataSize = TD.getTypeSize(OldElTy);
1108 Value *Index = I->getOperand(1);
1110 if (DataSize != 1) {
1111 // Insert a multiply of the old element type is not a unit size...
1113 if (Index->getType()->isSigned())
1114 CST = ConstantSInt::get(Index->getType(), DataSize);
1116 CST = ConstantUInt::get(Index->getType(), DataSize);
1118 Index = BinaryOperator::create(Instruction::Mul, Index, CST, "scale", It);
1121 // Perform the conversion now...
1123 std::vector<Value*> Indices;
1124 const Type *ElTy = ConvertibleToGEP(NewVal->getType(),Index,Indices,TD,&It);
1125 assert(ElTy != 0 && "GEP Conversion Failure!");
1126 Res = new GetElementPtrInst(NewVal, Indices, Name);
1127 assert(Res->getType() == PointerType::get(ElTy) &&
1128 "ConvertibleToGet failed!");
1131 if (I->getType() == PointerType::get(Type::SByteTy)) {
1132 // Convert a getelementptr sbyte * %reg111, uint 16 freely back to
1133 // anything that is a pointer type...
1135 BasicBlock::iterator It = I;
1137 // Check to see if the second argument is an expression that can
1138 // be converted to the appropriate size... if so, allow it.
1140 std::vector<Value*> Indices;
1141 const Type *ElTy = ConvertibleToGEP(NewVal->getType(), I->getOperand(1),
1143 assert(ElTy != 0 && "GEP Conversion Failure!");
1145 Res = new GetElementPtrInst(NewVal, Indices, Name);
1147 // Convert a getelementptr ulong * %reg123, uint %N
1148 // to getelementptr long * %reg123, uint %N
1149 // ... where the type must simply stay the same size...
1151 GetElementPtrInst *GEP = cast<GetElementPtrInst>(I);
1152 std::vector<Value*> Indices(GEP->idx_begin(), GEP->idx_end());
1153 Res = new GetElementPtrInst(NewVal, Indices, Name);
1158 case Instruction::PHI: {
1159 PHINode *OldPN = cast<PHINode>(I);
1160 PHINode *NewPN = new PHINode(NewTy, Name);
1161 VMC.ExprMap[I] = NewPN;
1163 while (OldPN->getNumOperands()) {
1164 BasicBlock *BB = OldPN->getIncomingBlock(0);
1165 Value *OldVal = OldPN->getIncomingValue(0);
1166 ValueHandle OldValHandle(VMC, OldVal);
1167 OldPN->removeIncomingValue(BB, false);
1168 Value *V = ConvertExpressionToType(OldVal, NewTy, VMC, TD);
1169 NewPN->addIncoming(V, BB);
1175 case Instruction::Call: {
1176 Value *Meth = I->getOperand(0);
1177 std::vector<Value*> Params(I->op_begin()+1, I->op_end());
1179 if (Meth == OldVal) { // Changing the function pointer?
1180 const PointerType *NewPTy = cast<PointerType>(NewVal->getType());
1181 const FunctionType *NewTy = cast<FunctionType>(NewPTy->getElementType());
1183 if (NewTy->getReturnType() == Type::VoidTy)
1184 Name = ""; // Make sure not to name a void call!
1186 // Get an iterator to the call instruction so that we can insert casts for
1187 // operands if need be. Note that we do not require operands to be
1188 // convertible, we can insert casts if they are convertible but not
1189 // compatible. The reason for this is that we prefer to have resolved
1190 // functions but casted arguments if possible.
1192 BasicBlock::iterator It = I;
1194 // Convert over all of the call operands to their new types... but only
1195 // convert over the part that is not in the vararg section of the call.
1197 for (unsigned i = 0; i != NewTy->getNumParams(); ++i)
1198 if (Params[i]->getType() != NewTy->getParamType(i)) {
1199 // Create a cast to convert it to the right type, we know that this
1200 // is a lossless cast...
1202 Params[i] = new CastInst(Params[i], NewTy->getParamType(i),
1204 Params[i]->getName(), It);
1206 Meth = NewVal; // Update call destination to new value
1208 } else { // Changing an argument, must be in vararg area
1209 std::vector<Value*>::iterator OI =
1210 find(Params.begin(), Params.end(), OldVal);
1211 assert (OI != Params.end() && "Not using value!");
1216 Res = new CallInst(Meth, Params, Name);
1220 assert(0 && "Expression convertible, but don't know how to convert?");
1224 // If the instruction was newly created, insert it into the instruction
1227 BasicBlock::iterator It = I;
1228 assert(It != BB->end() && "Instruction not in own basic block??");
1229 BB->getInstList().insert(It, Res); // Keep It pointing to old instruction
1231 DEBUG(std::cerr << "COT CREATED: " << (void*)Res << " " << *Res
1232 << "In: " << (void*)I << " " << *I << "Out: " << (void*)Res
1235 // Add the instruction to the expression map
1236 VMC.ExprMap[I] = Res;
1238 if (I->getType() != Res->getType())
1239 ConvertValueToNewType(I, Res, VMC, TD);
1241 bool FromStart = true;
1242 Value::use_iterator UI;
1244 if (FromStart) UI = I->use_begin();
1245 if (UI == I->use_end()) break;
1247 if (isa<ValueHandle>(*UI)) {
1252 if (!FromStart) --UI;
1253 U->replaceUsesOfWith(I, Res);
1254 if (!FromStart) ++UI;
1261 ValueHandle::ValueHandle(ValueMapCache &VMC, Value *V)
1262 : Instruction(Type::VoidTy, UserOp1, ""), Cache(VMC) {
1263 //DEBUG(std::cerr << "VH AQUIRING: " << (void*)V << " " << V);
1264 Operands.push_back(Use(V, this));
1267 ValueHandle::ValueHandle(const ValueHandle &VH)
1268 : Instruction(Type::VoidTy, UserOp1, ""), Cache(VH.Cache) {
1269 //DEBUG(std::cerr << "VH AQUIRING: " << (void*)V << " " << V);
1270 Operands.push_back(Use((Value*)VH.getOperand(0), this));
1273 static void RecursiveDelete(ValueMapCache &Cache, Instruction *I) {
1274 if (!I || !I->use_empty()) return;
1276 assert(I->getParent() && "Inst not in basic block!");
1278 //DEBUG(std::cerr << "VH DELETING: " << (void*)I << " " << I);
1280 for (User::op_iterator OI = I->op_begin(), OE = I->op_end();
1282 if (Instruction *U = dyn_cast<Instruction>(OI)) {
1284 RecursiveDelete(Cache, U);
1287 I->getParent()->getInstList().remove(I);
1289 Cache.OperandsMapped.erase(I);
1290 Cache.ExprMap.erase(I);
1294 ValueHandle::~ValueHandle() {
1295 if (Operands[0]->hasOneUse()) {
1296 Value *V = Operands[0];
1297 Operands[0] = 0; // Drop use!
1299 // Now we just need to remove the old instruction so we don't get infinite
1300 // loops. Note that we cannot use DCE because DCE won't remove a store
1301 // instruction, for example.
1303 RecursiveDelete(Cache, dyn_cast<Instruction>(V));
1305 //DEBUG(std::cerr << "VH RELEASING: " << (void*)Operands[0].get() << " "
1306 // << Operands[0]->use_size() << " " << Operands[0]);