1 //===- ExprTypeConvert.cpp - Code to change an LLVM Expr Type ---------------=//
3 // This file implements the part of level raising that checks to see if it is
4 // possible to coerce an entire expression tree into a different type. If
5 // convertable, other routines from this file will do the conversion.
7 //===----------------------------------------------------------------------===//
9 #include "TransformInternals.h"
10 #include "llvm/Method.h"
11 #include "llvm/iOther.h"
12 #include "llvm/iPHINode.h"
13 #include "llvm/iMemory.h"
14 #include "llvm/ConstantVals.h"
15 #include "llvm/Optimizations/ConstantHandling.h"
16 #include "llvm/Optimizations/DCE.h"
17 #include "llvm/Analysis/Expressions.h"
18 #include "Support/STLExtras.h"
22 #include "llvm/Assembly/Writer.h"
24 //#define DEBUG_EXPR_CONVERT 1
26 static bool OperandConvertableToType(User *U, Value *V, const Type *Ty,
27 ValueTypeCache &ConvertedTypes);
29 static void ConvertOperandToType(User *U, Value *OldVal, Value *NewVal,
32 // AllIndicesZero - Return true if all of the indices of the specified memory
33 // access instruction are zero, indicating an effectively nil offset to the
36 static bool AllIndicesZero(const MemAccessInst *MAI) {
37 for (User::const_op_iterator S = MAI->idx_begin(), E = MAI->idx_end();
39 if (!isa<Constant>(*S) || !cast<Constant>(*S)->isNullValue())
44 static unsigned getBaseTypeSize(const Type *Ty) {
45 if (const ArrayType *ATy = dyn_cast<ArrayType>(Ty))
47 return getBaseTypeSize(ATy->getElementType());
48 return TD.getTypeSize(Ty);
52 // Peephole Malloc instructions: we take a look at the use chain of the
53 // malloc instruction, and try to find out if the following conditions hold:
54 // 1. The malloc is of the form: 'malloc [sbyte], uint <constant>'
55 // 2. The only users of the malloc are cast & add instructions
56 // 3. Of the cast instructions, there is only one destination pointer type
57 // [RTy] where the size of the pointed to object is equal to the number
58 // of bytes allocated.
60 // If these conditions hold, we convert the malloc to allocate an [RTy]
61 // element. TODO: This comment is out of date WRT arrays
63 static bool MallocConvertableToType(MallocInst *MI, const Type *Ty,
64 ValueTypeCache &CTMap) {
65 if (!MI->isArrayAllocation() || // No array allocation?
66 !isa<PointerType>(Ty)) return false; // Malloc always returns pointers
68 // Deal with the type to allocate, not the pointer type...
69 Ty = cast<PointerType>(Ty)->getElementType();
71 // Analyze the number of bytes allocated...
72 analysis::ExprType Expr = analysis::ClassifyExpression(MI->getArraySize());
74 // Must have a scale or offset to analyze it...
75 if (!Expr.Offset && !Expr.Scale) return false;
77 if (Expr.Offset && (Expr.Scale || Expr.Var)) {
78 // This is wierd, shouldn't happen, but if it does, I wanna know about it!
79 cerr << "LevelRaise.cpp: Crazy allocation detected!\n";
83 // Get the number of bytes allocated...
84 int SizeVal = getConstantValue(Expr.Offset ? Expr.Offset : Expr.Scale);
86 cerr << "malloc of a negative number???\n";
89 unsigned Size = (unsigned)SizeVal;
90 unsigned ReqTypeSize = getBaseTypeSize(Ty);
92 // Does the size of the allocated type match the number of bytes
95 if (ReqTypeSize == Size)
98 // If not, it's possible that an array of constant size is being allocated.
99 // In this case, the Size will be a multiple of the data size.
101 if (!Expr.Offset) return false; // Offset must be set, not scale...
105 #else // THIS CAN ONLY BE RUN VERY LATE, after several passes to make sure
106 // things are adequately raised!
107 // See if the allocated amount is a multiple of the type size...
108 if (Size/ReqTypeSize*ReqTypeSize != Size)
109 return false; // Nope.
111 // Unfortunately things tend to be powers of two, so there may be
112 // many false hits. We don't want to optimistically assume that we
113 // have the right type on the first try, so scan the use list of the
114 // malloc instruction, looking for the cast to the biggest type...
116 for (Value::use_iterator I = MI->use_begin(), E = MI->use_end(); I != E; ++I)
117 if (CastInst *CI = dyn_cast<CastInst>(*I))
118 if (const PointerType *PT =
119 dyn_cast<PointerType>(CI->getOperand(0)->getType()))
120 if (getBaseTypeSize(PT->getElementType()) > ReqTypeSize)
121 return false; // We found a type bigger than this one!
127 static Instruction *ConvertMallocToType(MallocInst *MI, const Type *Ty,
128 const string &Name, ValueMapCache &VMC){
129 BasicBlock *BB = MI->getParent();
130 BasicBlock::iterator It = BB->end();
132 // Analyze the number of bytes allocated...
133 analysis::ExprType Expr = analysis::ClassifyExpression(MI->getArraySize());
135 const PointerType *AllocTy = cast<PointerType>(Ty);
136 const Type *ElType = AllocTy->getElementType();
138 if (Expr.Var && !isa<ArrayType>(ElType)) {
139 ElType = ArrayType::get(AllocTy->getElementType());
140 AllocTy = PointerType::get(ElType);
143 // If the array size specifier is not an unsigned integer, insert a cast now.
144 if (Expr.Var && Expr.Var->getType() != Type::UIntTy) {
145 It = find(BB->getInstList().begin(), BB->getInstList().end(), MI);
146 CastInst *SizeCast = new CastInst(Expr.Var, Type::UIntTy);
147 It = BB->getInstList().insert(It, SizeCast)+1;
151 // Check to see if they are allocating a constant sized array of a type...
152 #if 0 // THIS CAN ONLY BE RUN VERY LATE
154 unsigned OffsetAmount = (unsigned)getConstantValue(Expr.Offset);
155 unsigned DataSize = TD.getTypeSize(ElType);
157 if (OffsetAmount > DataSize) // Allocate a sized array amount...
158 Expr.Var = ConstantUInt::get(Type::UIntTy, OffsetAmount/DataSize);
162 Instruction *NewI = new MallocInst(AllocTy, Expr.Var, Name);
164 if (AllocTy != Ty) { // Create a cast instruction to cast it to the correct ty
166 It = find(BB->getInstList().begin(), BB->getInstList().end(), MI);
168 // Insert the new malloc directly into the code ourselves
169 assert(It != BB->getInstList().end());
170 It = BB->getInstList().insert(It, NewI)+1;
172 // Return the cast as the value to use...
173 NewI = new CastInst(NewI, Ty);
180 // ExpressionConvertableToType - Return true if it is possible
181 bool ExpressionConvertableToType(Value *V, const Type *Ty,
182 ValueTypeCache &CTMap) {
183 if (V->getType() == Ty) return true; // Expression already correct type!
185 // Expression type must be holdable in a register.
186 if (!isFirstClassType(Ty))
189 ValueTypeCache::iterator CTMI = CTMap.find(V);
190 if (CTMI != CTMap.end()) return CTMI->second == Ty;
194 Instruction *I = dyn_cast<Instruction>(V);
196 // It's not an instruction, check to see if it's a constant... all constants
197 // can be converted to an equivalent value (except pointers, they can't be
198 // const prop'd in general). We just ask the constant propogator to see if
199 // it can convert the value...
201 if (Constant *CPV = dyn_cast<Constant>(V))
202 if (opt::ConstantFoldCastInstruction(CPV, Ty))
203 return true; // Don't worry about deallocating, it's a constant.
205 return false; // Otherwise, we can't convert!
208 switch (I->getOpcode()) {
209 case Instruction::Cast:
210 // We can convert the expr if the cast destination type is losslessly
211 // convertable to the requested type.
212 if (!Ty->isLosslesslyConvertableTo(I->getType())) return false;
214 // We also do not allow conversion of a cast that casts from a ptr to array
215 // of X to a *X. For example: cast [4 x %List *] * %val to %List * *
217 if (PointerType *SPT = dyn_cast<PointerType>(I->getOperand(0)->getType()))
218 if (PointerType *DPT = dyn_cast<PointerType>(I->getType()))
219 if (ArrayType *AT = dyn_cast<ArrayType>(SPT->getElementType()))
220 if (AT->getElementType() == DPT->getElementType())
225 case Instruction::Add:
226 case Instruction::Sub:
227 if (!ExpressionConvertableToType(I->getOperand(0), Ty, CTMap) ||
228 !ExpressionConvertableToType(I->getOperand(1), Ty, CTMap))
231 case Instruction::Shr:
232 if (Ty->isSigned() != V->getType()->isSigned()) return false;
234 case Instruction::Shl:
235 if (!ExpressionConvertableToType(I->getOperand(0), Ty, CTMap))
239 case Instruction::Load: {
240 LoadInst *LI = cast<LoadInst>(I);
241 if (LI->hasIndices() && !AllIndicesZero(LI)) {
242 // We can't convert a load expression if it has indices... unless they are
247 if (!ExpressionConvertableToType(LI->getPointerOperand(),
248 PointerType::get(Ty), CTMap))
252 case Instruction::PHINode: {
253 PHINode *PN = cast<PHINode>(I);
254 for (unsigned i = 0; i < PN->getNumIncomingValues(); ++i)
255 if (!ExpressionConvertableToType(PN->getIncomingValue(i), Ty, CTMap))
260 case Instruction::Malloc:
261 if (!MallocConvertableToType(cast<MallocInst>(I), Ty, CTMap))
266 case Instruction::GetElementPtr: {
267 // GetElementPtr's are directly convertable to a pointer type if they have
268 // a number of zeros at the end. Because removing these values does not
269 // change the logical offset of the GEP, it is okay and fair to remove them.
270 // This can change this:
271 // %t1 = getelementptr %Hosp * %hosp, ubyte 4, ubyte 0 ; <%List **>
272 // %t2 = cast %List * * %t1 to %List *
274 // %t2 = getelementptr %Hosp * %hosp, ubyte 4 ; <%List *>
276 GetElementPtrInst *GEP = cast<GetElementPtrInst>(I);
277 const PointerType *PTy = dyn_cast<PointerType>(Ty);
278 if (!PTy) return false;
280 // Check to see if there are zero elements that we can remove from the
281 // index array. If there are, check to see if removing them causes us to
282 // get to the right type...
284 vector<Value*> Indices = GEP->copyIndices();
285 const Type *BaseType = GEP->getPointerOperand()->getType();
286 const Type *ElTy = 0;
288 while (!Indices.empty() && isa<ConstantUInt>(Indices.back()) &&
289 cast<ConstantUInt>(Indices.back())->getValue() == 0) {
291 ElTy = GetElementPtrInst::getIndexedType(BaseType, Indices,
293 if (ElTy == PTy->getElementType())
294 break; // Found a match!!
299 return false; // No match, maybe next time.
307 // Expressions are only convertable if all of the users of the expression can
308 // have this value converted. This makes use of the map to avoid infinite
311 for (Value::use_iterator It = I->use_begin(), E = I->use_end(); It != E; ++It)
312 if (!OperandConvertableToType(*It, I, Ty, CTMap))
319 Value *ConvertExpressionToType(Value *V, const Type *Ty, ValueMapCache &VMC) {
320 if (V->getType() == Ty) return V; // Already where we need to be?
322 ValueMapCache::ExprMapTy::iterator VMCI = VMC.ExprMap.find(V);
323 if (VMCI != VMC.ExprMap.end()) {
324 assert(VMCI->second->getType() == Ty);
328 #ifdef DEBUG_EXPR_CONVERT
329 cerr << "CETT: " << (void*)V << " " << V;
332 Instruction *I = dyn_cast<Instruction>(V);
334 if (Constant *CPV = cast<Constant>(V)) {
335 // Constants are converted by constant folding the cast that is required.
336 // We assume here that all casts are implemented for constant prop.
337 Value *Result = opt::ConstantFoldCastInstruction(CPV, Ty);
338 assert(Result && "ConstantFoldCastInstruction Failed!!!");
339 assert(Result->getType() == Ty && "Const prop of cast failed!");
341 // Add the instruction to the expression map
342 VMC.ExprMap[V] = Result;
347 BasicBlock *BB = I->getParent();
348 BasicBlock::InstListType &BIL = BB->getInstList();
349 string Name = I->getName(); if (!Name.empty()) I->setName("");
350 Instruction *Res; // Result of conversion
352 ValueHandle IHandle(VMC, I); // Prevent I from being removed!
354 Constant *Dummy = Constant::getNullConstant(Ty);
356 //cerr << endl << endl << "Type:\t" << Ty << "\nInst: " << I << "BB Before: " << BB << endl;
358 switch (I->getOpcode()) {
359 case Instruction::Cast:
360 Res = new CastInst(I->getOperand(0), Ty, Name);
363 case Instruction::Add:
364 case Instruction::Sub:
365 Res = BinaryOperator::create(cast<BinaryOperator>(I)->getOpcode(),
367 VMC.ExprMap[I] = Res; // Add node to expression eagerly
369 Res->setOperand(0, ConvertExpressionToType(I->getOperand(0), Ty, VMC));
370 Res->setOperand(1, ConvertExpressionToType(I->getOperand(1), Ty, VMC));
373 case Instruction::Shl:
374 case Instruction::Shr:
375 Res = new ShiftInst(cast<ShiftInst>(I)->getOpcode(), Dummy,
376 I->getOperand(1), Name);
377 VMC.ExprMap[I] = Res;
378 Res->setOperand(0, ConvertExpressionToType(I->getOperand(0), Ty, VMC));
381 case Instruction::Load: {
382 LoadInst *LI = cast<LoadInst>(I);
383 assert(!LI->hasIndices() || AllIndicesZero(LI));
385 Res = new LoadInst(Constant::getNullConstant(PointerType::get(Ty)), Name);
386 VMC.ExprMap[I] = Res;
387 Res->setOperand(0, ConvertExpressionToType(LI->getPointerOperand(),
388 PointerType::get(Ty), VMC));
389 assert(Res->getOperand(0)->getType() == PointerType::get(Ty));
390 assert(Ty == Res->getType());
391 assert(isFirstClassType(Res->getType()) && "Load of structure or array!");
395 case Instruction::PHINode: {
396 PHINode *OldPN = cast<PHINode>(I);
397 PHINode *NewPN = new PHINode(Ty, Name);
399 VMC.ExprMap[I] = NewPN; // Add node to expression eagerly
400 while (OldPN->getNumOperands()) {
401 BasicBlock *BB = OldPN->getIncomingBlock(0);
402 Value *OldVal = OldPN->getIncomingValue(0);
403 ValueHandle OldValHandle(VMC, OldVal);
404 OldPN->removeIncomingValue(BB);
405 Value *V = ConvertExpressionToType(OldVal, Ty, VMC);
406 NewPN->addIncoming(V, BB);
412 case Instruction::Malloc: {
413 Res = ConvertMallocToType(cast<MallocInst>(I), Ty, Name, VMC);
417 case Instruction::GetElementPtr: {
418 // GetElementPtr's are directly convertable to a pointer type if they have
419 // a number of zeros at the end. Because removing these values does not
420 // change the logical offset of the GEP, it is okay and fair to remove them.
421 // This can change this:
422 // %t1 = getelementptr %Hosp * %hosp, ubyte 4, ubyte 0 ; <%List **>
423 // %t2 = cast %List * * %t1 to %List *
425 // %t2 = getelementptr %Hosp * %hosp, ubyte 4 ; <%List *>
427 GetElementPtrInst *GEP = cast<GetElementPtrInst>(I);
429 // Check to see if there are zero elements that we can remove from the
430 // index array. If there are, check to see if removing them causes us to
431 // get to the right type...
433 vector<Value*> Indices = GEP->copyIndices();
434 const Type *BaseType = GEP->getPointerOperand()->getType();
435 const Type *PVTy = cast<PointerType>(Ty)->getElementType();
437 while (!Indices.empty() && isa<ConstantUInt>(Indices.back()) &&
438 cast<ConstantUInt>(Indices.back())->getValue() == 0) {
440 if (GetElementPtrInst::getIndexedType(BaseType, Indices, true) == PVTy) {
441 if (Indices.size() == 0) {
442 Res = new CastInst(GEP->getPointerOperand(), BaseType); // NOOP
444 Res = new GetElementPtrInst(GEP->getPointerOperand(), Indices, Name);
449 assert(Res && "Didn't find match!");
450 break; // No match, maybe next time.
454 assert(0 && "Expression convertable, but don't know how to convert?");
458 assert(Res->getType() == Ty && "Didn't convert expr to correct type!");
460 BasicBlock::iterator It = find(BIL.begin(), BIL.end(), I);
461 assert(It != BIL.end() && "Instruction not in own basic block??");
464 // Add the instruction to the expression map
465 VMC.ExprMap[I] = Res;
467 // Expressions are only convertable if all of the users of the expression can
468 // have this value converted. This makes use of the map to avoid infinite
471 unsigned NumUses = I->use_size();
472 for (unsigned It = 0; It < NumUses; ) {
473 unsigned OldSize = NumUses;
474 ConvertOperandToType(*(I->use_begin()+It), I, Res, VMC);
475 NumUses = I->use_size();
476 if (NumUses == OldSize) ++It;
479 #ifdef DEBUG_EXPR_CONVERT
480 cerr << "ExpIn: " << (void*)I << " " << I
481 << "ExpOut: " << (void*)Res << " " << Res;
484 if (I->use_empty()) {
485 #ifdef DEBUG_EXPR_CONVERT
486 cerr << "EXPR DELETING: " << (void*)I << " " << I;
489 VMC.OperandsMapped.erase(I);
490 VMC.ExprMap.erase(I);
499 // ValueConvertableToType - Return true if it is possible
500 bool ValueConvertableToType(Value *V, const Type *Ty,
501 ValueTypeCache &ConvertedTypes) {
502 ValueTypeCache::iterator I = ConvertedTypes.find(V);
503 if (I != ConvertedTypes.end()) return I->second == Ty;
504 ConvertedTypes[V] = Ty;
506 // It is safe to convert the specified value to the specified type IFF all of
507 // the uses of the value can be converted to accept the new typed value.
509 for (Value::use_iterator I = V->use_begin(), E = V->use_end(); I != E; ++I)
510 if (!OperandConvertableToType(*I, V, Ty, ConvertedTypes))
520 // OperandConvertableToType - Return true if it is possible to convert operand
521 // V of User (instruction) U to the specified type. This is true iff it is
522 // possible to change the specified instruction to accept this. CTMap is a map
523 // of converted types, so that circular definitions will see the future type of
524 // the expression, not the static current type.
526 static bool OperandConvertableToType(User *U, Value *V, const Type *Ty,
527 ValueTypeCache &CTMap) {
528 if (V->getType() == Ty) return true; // Operand already the right type?
530 // Expression type must be holdable in a register.
531 if (!isFirstClassType(Ty))
534 Instruction *I = dyn_cast<Instruction>(U);
535 if (I == 0) return false; // We can't convert!
537 switch (I->getOpcode()) {
538 case Instruction::Cast:
539 assert(I->getOperand(0) == V);
540 // We can convert the expr if the cast destination type is losslessly
541 // convertable to the requested type.
542 if (!Ty->isLosslesslyConvertableTo(I->getOperand(0)->getType()))
545 // We also do not allow conversion of a cast that casts from a ptr to array
546 // of X to a *X. For example: cast [4 x %List *] * %val to %List * *
548 if (PointerType *SPT = dyn_cast<PointerType>(I->getOperand(0)->getType()))
549 if (PointerType *DPT = dyn_cast<PointerType>(I->getType()))
550 if (ArrayType *AT = dyn_cast<ArrayType>(SPT->getElementType()))
551 if (AT->getElementType() == DPT->getElementType())
556 case Instruction::Add:
557 if (isa<PointerType>(Ty)) {
558 Value *IndexVal = I->getOperand(V == I->getOperand(0) ? 1 : 0);
559 vector<Value*> Indices;
560 if (const Type *ETy = ConvertableToGEP(Ty, IndexVal, Indices)) {
561 const Type *RetTy = PointerType::get(ETy);
563 // Only successful if we can convert this type to the required type
564 if (ValueConvertableToType(I, RetTy, CTMap)) {
571 case Instruction::Sub: {
572 Value *OtherOp = I->getOperand((V == I->getOperand(0)) ? 1 : 0);
573 return ValueConvertableToType(I, Ty, CTMap) &&
574 ExpressionConvertableToType(OtherOp, Ty, CTMap);
576 case Instruction::SetEQ:
577 case Instruction::SetNE: {
578 Value *OtherOp = I->getOperand((V == I->getOperand(0)) ? 1 : 0);
579 return ExpressionConvertableToType(OtherOp, Ty, CTMap);
581 case Instruction::Shr:
582 if (Ty->isSigned() != V->getType()->isSigned()) return false;
584 case Instruction::Shl:
585 assert(I->getOperand(0) == V);
586 return ValueConvertableToType(I, Ty, CTMap);
588 case Instruction::Load:
589 // Cannot convert the types of any subscripts...
590 if (I->getOperand(0) != V) return false;
592 if (const PointerType *PT = dyn_cast<PointerType>(Ty)) {
593 LoadInst *LI = cast<LoadInst>(I);
595 if (LI->hasIndices() && !AllIndicesZero(LI))
598 const Type *LoadedTy = PT->getElementType();
600 // They could be loading the first element of a composite type...
601 if (const CompositeType *CT = dyn_cast<CompositeType>(LoadedTy)) {
602 unsigned Offset = 0; // No offset, get first leaf.
603 vector<Value*> Indices; // Discarded...
604 LoadedTy = getStructOffsetType(CT, Offset, Indices, false);
605 assert(Offset == 0 && "Offset changed from zero???");
608 if (!isFirstClassType(LoadedTy))
611 if (TD.getTypeSize(LoadedTy) != TD.getTypeSize(LI->getType()))
614 return ValueConvertableToType(LI, LoadedTy, CTMap);
618 case Instruction::Store: {
619 StoreInst *SI = cast<StoreInst>(I);
620 if (SI->hasIndices()) return false;
622 if (V == I->getOperand(0)) {
623 // Can convert the store if we can convert the pointer operand to match
624 // the new value type...
625 return ExpressionConvertableToType(I->getOperand(1), PointerType::get(Ty),
627 } else if (const PointerType *PT = dyn_cast<PointerType>(Ty)) {
628 const Type *ElTy = PT->getElementType();
629 if (ArrayType *AT = dyn_cast<ArrayType>(ElTy))
630 ElTy = AT->getElementType(); // Avoid getDataSize on unsized array type!
631 assert(V == I->getOperand(1));
633 // Must move the same amount of data...
634 if (TD.getTypeSize(ElTy) != TD.getTypeSize(I->getOperand(0)->getType()))
637 // Can convert store if the incoming value is convertable...
638 return ExpressionConvertableToType(I->getOperand(0), ElTy, CTMap);
643 case Instruction::GetElementPtr:
644 // Convert a getelementptr [sbyte] * %reg111, uint 16 freely back to
645 // anything that is a pointer type...
647 if (I->getType() != PointerType::get(Type::SByteTy) ||
648 I->getNumOperands() != 2 || V != I->getOperand(0) ||
649 I->getOperand(1)->getType() != Type::UIntTy || !isa<PointerType>(Ty))
653 case Instruction::PHINode: {
654 PHINode *PN = cast<PHINode>(I);
655 for (unsigned i = 0; i < PN->getNumIncomingValues(); ++i)
656 if (!ExpressionConvertableToType(PN->getIncomingValue(i), Ty, CTMap))
658 return ValueConvertableToType(PN, Ty, CTMap);
661 case Instruction::Call: {
662 User::op_iterator OI = find(I->op_begin(), I->op_end(), V);
663 assert (OI != I->op_end() && "Not using value!");
664 unsigned OpNum = OI - I->op_begin();
667 return false; // Can't convert method pointer type yet. FIXME
669 const PointerType *MPtr = cast<PointerType>(I->getOperand(0)->getType());
670 const MethodType *MTy = cast<MethodType>(MPtr->getElementType());
671 if (!MTy->isVarArg()) return false;
673 if ((OpNum-1) < MTy->getParamTypes().size())
674 return false; // It's not in the varargs section...
676 // If we get this far, we know the value is in the varargs section of the
677 // method! We can convert if we don't reinterpret the value...
679 return Ty->isLosslesslyConvertableTo(V->getType());
686 void ConvertValueToNewType(Value *V, Value *NewVal, ValueMapCache &VMC) {
687 ValueHandle VH(VMC, V);
689 unsigned NumUses = V->use_size();
690 for (unsigned It = 0; It < NumUses; ) {
691 unsigned OldSize = NumUses;
692 ConvertOperandToType(*(V->use_begin()+It), V, NewVal, VMC);
693 NumUses = V->use_size();
694 if (NumUses == OldSize) ++It;
700 static void ConvertOperandToType(User *U, Value *OldVal, Value *NewVal,
701 ValueMapCache &VMC) {
702 if (isa<ValueHandle>(U)) return; // Valuehandles don't let go of operands...
704 if (VMC.OperandsMapped.count(U)) return;
705 VMC.OperandsMapped.insert(U);
707 ValueMapCache::ExprMapTy::iterator VMCI = VMC.ExprMap.find(U);
708 if (VMCI != VMC.ExprMap.end())
712 Instruction *I = cast<Instruction>(U); // Only Instructions convertable
714 BasicBlock *BB = I->getParent();
715 BasicBlock::InstListType &BIL = BB->getInstList();
716 string Name = I->getName(); if (!Name.empty()) I->setName("");
717 Instruction *Res; // Result of conversion
719 //cerr << endl << endl << "Type:\t" << Ty << "\nInst: " << I << "BB Before: " << BB << endl;
721 // Prevent I from being removed...
722 ValueHandle IHandle(VMC, I);
724 const Type *NewTy = NewVal->getType();
725 Constant *Dummy = (NewTy != Type::VoidTy) ?
726 Constant::getNullConstant(NewTy) : 0;
728 switch (I->getOpcode()) {
729 case Instruction::Cast:
730 assert(I->getOperand(0) == OldVal);
731 Res = new CastInst(NewVal, I->getType(), Name);
734 case Instruction::Add:
735 if (isa<PointerType>(NewTy)) {
736 Value *IndexVal = I->getOperand(OldVal == I->getOperand(0) ? 1 : 0);
737 vector<Value*> Indices;
738 BasicBlock::iterator It = find(BIL.begin(), BIL.end(), I);
740 if (const Type *ETy = ConvertableToGEP(NewTy, IndexVal, Indices, &It)) {
741 // If successful, convert the add to a GEP
742 const Type *RetTy = PointerType::get(ETy);
743 // First operand is actually the given pointer...
744 Res = new GetElementPtrInst(NewVal, Indices, Name);
745 assert(cast<PointerType>(Res->getType())->getElementType() == ETy &&
746 "ConvertableToGEP broken!");
752 case Instruction::Sub:
753 case Instruction::SetEQ:
754 case Instruction::SetNE: {
755 Res = BinaryOperator::create(cast<BinaryOperator>(I)->getOpcode(),
757 VMC.ExprMap[I] = Res; // Add node to expression eagerly
759 unsigned OtherIdx = (OldVal == I->getOperand(0)) ? 1 : 0;
760 Value *OtherOp = I->getOperand(OtherIdx);
761 Value *NewOther = ConvertExpressionToType(OtherOp, NewTy, VMC);
763 Res->setOperand(OtherIdx, NewOther);
764 Res->setOperand(!OtherIdx, NewVal);
767 case Instruction::Shl:
768 case Instruction::Shr:
769 assert(I->getOperand(0) == OldVal);
770 Res = new ShiftInst(cast<ShiftInst>(I)->getOpcode(), NewVal,
771 I->getOperand(1), Name);
774 case Instruction::Load: {
775 assert(I->getOperand(0) == OldVal && isa<PointerType>(NewVal->getType()));
776 const Type *LoadedTy = cast<PointerType>(NewVal->getType())->getElementType();
778 vector<Value*> Indices;
780 if (const CompositeType *CT = dyn_cast<CompositeType>(LoadedTy)) {
781 unsigned Offset = 0; // No offset, get first leaf.
782 LoadedTy = getStructOffsetType(CT, Offset, Indices, false);
784 assert(isFirstClassType(LoadedTy));
786 Res = new LoadInst(NewVal, Indices, Name);
787 assert(isFirstClassType(Res->getType()) && "Load of structure or array!");
791 case Instruction::Store: {
792 if (I->getOperand(0) == OldVal) { // Replace the source value
793 const PointerType *NewPT = PointerType::get(NewTy);
794 Res = new StoreInst(NewVal, Constant::getNullConstant(NewPT));
795 VMC.ExprMap[I] = Res;
796 Res->setOperand(1, ConvertExpressionToType(I->getOperand(1), NewPT, VMC));
797 } else { // Replace the source pointer
798 const Type *ValTy = cast<PointerType>(NewTy)->getElementType();
799 vector<Value*> Indices;
800 while (ArrayType *AT = dyn_cast<ArrayType>(ValTy)) {
801 Indices.push_back(ConstantUInt::get(Type::UIntTy, 0));
802 ValTy = AT->getElementType();
805 Res = new StoreInst(Constant::getNullConstant(ValTy), NewVal, Indices);
806 VMC.ExprMap[I] = Res;
807 Res->setOperand(0, ConvertExpressionToType(I->getOperand(0), ValTy, VMC));
813 case Instruction::GetElementPtr: {
814 // Convert a getelementptr [sbyte] * %reg111, uint 16 freely back to
815 // anything that is a pointer type...
817 BasicBlock::iterator It = find(BIL.begin(), BIL.end(), I);
819 // Insert a cast right before this instruction of the index value...
820 CastInst *CIdx = new CastInst(I->getOperand(1), NewTy);
821 It = BIL.insert(It, CIdx)+1;
823 // Insert an add right before this instruction
824 Instruction *AddInst = BinaryOperator::create(Instruction::Add, NewVal,
826 It = BIL.insert(It, AddInst)+1;
828 // Finally, cast the result back to our previous type...
829 Res = new CastInst(AddInst, I->getType());
833 case Instruction::PHINode: {
834 PHINode *OldPN = cast<PHINode>(I);
835 PHINode *NewPN = new PHINode(NewTy, Name);
836 VMC.ExprMap[I] = NewPN;
838 while (OldPN->getNumOperands()) {
839 BasicBlock *BB = OldPN->getIncomingBlock(0);
840 Value *OldVal = OldPN->getIncomingValue(0);
841 OldPN->removeIncomingValue(BB);
842 Value *V = ConvertExpressionToType(OldVal, NewTy, VMC);
843 NewPN->addIncoming(V, BB);
849 case Instruction::Call: {
850 Value *Meth = I->getOperand(0);
851 vector<Value*> Params(I->op_begin()+1, I->op_end());
853 vector<Value*>::iterator OI = find(Params.begin(), Params.end(), OldVal);
854 assert (OI != Params.end() && "Not using value!");
857 Res = new CallInst(Meth, Params, Name);
861 assert(0 && "Expression convertable, but don't know how to convert?");
865 BasicBlock::iterator It = find(BIL.begin(), BIL.end(), I);
866 assert(It != BIL.end() && "Instruction not in own basic block??");
867 BIL.insert(It, Res); // Keep It pointing to old instruction
869 #ifdef DEBUG_EXPR_CONVERT
870 cerr << "COT CREATED: " << (void*)Res << " " << Res;
871 cerr << "In: " << (void*)I << " " << I << "Out: " << (void*)Res << " " << Res;
874 // Add the instruction to the expression map
875 VMC.ExprMap[I] = Res;
877 if (I->getType() != Res->getType())
878 ConvertValueToNewType(I, Res, VMC);
880 for (unsigned It = 0; It < I->use_size(); ) {
881 User *Use = *(I->use_begin()+It);
882 if (isa<ValueHandle>(Use)) // Don't remove ValueHandles!
885 Use->replaceUsesOfWith(I, Res);
888 if (I->use_empty()) {
889 // Now we just need to remove the old instruction so we don't get infinite
890 // loops. Note that we cannot use DCE because DCE won't remove a store
891 // instruction, for example.
893 #ifdef DEBUG_EXPR_CONVERT
894 cerr << "DELETING: " << (void*)I << " " << I;
897 VMC.OperandsMapped.erase(I);
898 VMC.ExprMap.erase(I);
901 for (Value::use_iterator UI = I->use_begin(), UE = I->use_end();
903 assert(isa<ValueHandle>((Value*)*UI) &&"Uses of Instruction remain!!!");
909 ValueHandle::ValueHandle(ValueMapCache &VMC, Value *V)
910 : Instruction(Type::VoidTy, UserOp1, ""), Cache(VMC) {
911 #ifdef DEBUG_EXPR_CONVERT
912 //cerr << "VH AQUIRING: " << (void*)V << " " << V;
914 Operands.push_back(Use(V, this));
917 static void RecursiveDelete(ValueMapCache &Cache, Instruction *I) {
918 if (!I || !I->use_empty()) return;
920 assert(I->getParent() && "Inst not in basic block!");
922 #ifdef DEBUG_EXPR_CONVERT
923 //cerr << "VH DELETING: " << (void*)I << " " << I;
926 for (User::op_iterator OI = I->op_begin(), OE = I->op_end();
928 Instruction *U = dyn_cast<Instruction>(*OI);
931 RecursiveDelete(Cache, dyn_cast<Instruction>(U));
935 I->getParent()->getInstList().remove(I);
937 Cache.OperandsMapped.erase(I);
938 Cache.ExprMap.erase(I);
942 ValueHandle::~ValueHandle() {
943 if (Operands[0]->use_size() == 1) {
944 Value *V = Operands[0];
945 Operands[0] = 0; // Drop use!
947 // Now we just need to remove the old instruction so we don't get infinite
948 // loops. Note that we cannot use DCE because DCE won't remove a store
949 // instruction, for example.
951 RecursiveDelete(Cache, dyn_cast<Instruction>(V));
953 #ifdef DEBUG_EXPR_CONVERT
954 //cerr << "VH RELEASING: " << (void*)Operands[0].get() << " " << Operands[0]->use_size() << " " << Operands[0];