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-rw-r--r--lib/Transforms/Scalar/SROA.cpp155
1 files changed, 110 insertions, 45 deletions
diff --git a/lib/Transforms/Scalar/SROA.cpp b/lib/Transforms/Scalar/SROA.cpp
index 5c55143..9f3fc83 100644
--- a/lib/Transforms/Scalar/SROA.cpp
+++ b/lib/Transforms/Scalar/SROA.cpp
@@ -733,9 +733,9 @@ class AllocaPromoter : public LoadAndStorePromoter {
SmallVector<DbgValueInst *, 4> DVIs;
public:
- AllocaPromoter(const SmallVectorImpl<Instruction*> &Insts, SSAUpdater &S,
+ AllocaPromoter(const SmallVectorImpl<Instruction *> &Insts, SSAUpdater &S,
AllocaInst &AI, DIBuilder &DIB)
- : LoadAndStorePromoter(Insts, S), AI(AI), DIB(DIB) {}
+ : LoadAndStorePromoter(Insts, S), AI(AI), DIB(DIB) {}
void run(const SmallVectorImpl<Instruction*> &Insts) {
// Retain the debug information attached to the alloca for use when
@@ -762,9 +762,30 @@ public:
virtual bool isInstInList(Instruction *I,
const SmallVectorImpl<Instruction*> &Insts) const {
+ Value *Ptr;
if (LoadInst *LI = dyn_cast<LoadInst>(I))
- return LI->getOperand(0) == &AI;
- return cast<StoreInst>(I)->getPointerOperand() == &AI;
+ Ptr = LI->getOperand(0);
+ else
+ Ptr = cast<StoreInst>(I)->getPointerOperand();
+
+ // Only used to detect cycles, which will be rare and quickly found as
+ // we're walking up a chain of defs rather than down through uses.
+ SmallPtrSet<Value *, 4> Visited;
+
+ do {
+ if (Ptr == &AI)
+ return true;
+
+ if (BitCastInst *BCI = dyn_cast<BitCastInst>(Ptr))
+ Ptr = BCI->getOperand(0);
+ else if (GetElementPtrInst *GEPI = dyn_cast<GetElementPtrInst>(Ptr))
+ Ptr = GEPI->getPointerOperand();
+ else
+ return false;
+
+ } while (Visited.insert(Ptr));
+
+ return false;
}
virtual void updateDebugInfo(Instruction *Inst) const {
@@ -917,6 +938,7 @@ static Type *findCommonType(AllocaSlices::const_iterator B,
AllocaSlices::const_iterator E,
uint64_t EndOffset) {
Type *Ty = 0;
+ bool IgnoreNonIntegralTypes = false;
for (AllocaSlices::const_iterator I = B; I != E; ++I) {
Use *U = I->getUse();
if (isa<IntrinsicInst>(*U->getUser()))
@@ -925,29 +947,37 @@ static Type *findCommonType(AllocaSlices::const_iterator B,
continue;
Type *UserTy = 0;
- if (LoadInst *LI = dyn_cast<LoadInst>(U->getUser()))
+ if (LoadInst *LI = dyn_cast<LoadInst>(U->getUser())) {
UserTy = LI->getType();
- else if (StoreInst *SI = dyn_cast<StoreInst>(U->getUser()))
+ } else if (StoreInst *SI = dyn_cast<StoreInst>(U->getUser())) {
UserTy = SI->getValueOperand()->getType();
- else
- return 0; // Bail if we have weird uses.
+ } else {
+ IgnoreNonIntegralTypes = true; // Give up on anything but an iN type.
+ continue;
+ }
if (IntegerType *ITy = dyn_cast<IntegerType>(UserTy)) {
// If the type is larger than the partition, skip it. We only encounter
// this for split integer operations where we want to use the type of the
- // entity causing the split.
- if (ITy->getBitWidth() / 8 > (EndOffset - B->beginOffset()))
+ // entity causing the split. Also skip if the type is not a byte width
+ // multiple.
+ if (ITy->getBitWidth() % 8 != 0 ||
+ ITy->getBitWidth() / 8 > (EndOffset - B->beginOffset()))
continue;
// If we have found an integer type use covering the alloca, use that
- // regardless of the other types, as integers are often used for a
- // "bucket
- // of bits" type.
+ // regardless of the other types, as integers are often used for
+ // a "bucket of bits" type.
+ //
+ // NB: This *must* be the only return from inside the loop so that the
+ // order of slices doesn't impact the computed type.
return ITy;
+ } else if (IgnoreNonIntegralTypes) {
+ continue;
}
if (Ty && Ty != UserTy)
- return 0;
+ IgnoreNonIntegralTypes = true; // Give up on anything but an iN type.
Ty = UserTy;
}
@@ -1431,6 +1461,10 @@ static bool canConvertValue(const DataLayout &DL, Type *OldTy, Type *NewTy) {
if (!NewTy->isSingleValueType() || !OldTy->isSingleValueType())
return false;
+ // We can convert pointers to integers and vice-versa. Same for vectors
+ // of pointers and integers.
+ OldTy = OldTy->getScalarType();
+ NewTy = NewTy->getScalarType();
if (NewTy->isPointerTy() || OldTy->isPointerTy()) {
if (NewTy->isPointerTy() && OldTy->isPointerTy())
return true;
@@ -1449,21 +1483,53 @@ static bool canConvertValue(const DataLayout &DL, Type *OldTy, Type *NewTy) {
/// inttoptr, and ptrtoint casts. Use the \c canConvertValue predicate to test
/// two types for viability with this routine.
static Value *convertValue(const DataLayout &DL, IRBuilderTy &IRB, Value *V,
- Type *Ty) {
- assert(canConvertValue(DL, V->getType(), Ty) &&
- "Value not convertable to type");
- if (V->getType() == Ty)
+ Type *NewTy) {
+ Type *OldTy = V->getType();
+ assert(canConvertValue(DL, OldTy, NewTy) && "Value not convertable to type");
+
+ if (OldTy == NewTy)
return V;
- if (IntegerType *OldITy = dyn_cast<IntegerType>(V->getType()))
- if (IntegerType *NewITy = dyn_cast<IntegerType>(Ty))
+
+ if (IntegerType *OldITy = dyn_cast<IntegerType>(OldTy))
+ if (IntegerType *NewITy = dyn_cast<IntegerType>(NewTy))
if (NewITy->getBitWidth() > OldITy->getBitWidth())
return IRB.CreateZExt(V, NewITy);
- if (V->getType()->isIntegerTy() && Ty->isPointerTy())
- return IRB.CreateIntToPtr(V, Ty);
- if (V->getType()->isPointerTy() && Ty->isIntegerTy())
- return IRB.CreatePtrToInt(V, Ty);
- return IRB.CreateBitCast(V, Ty);
+ // See if we need inttoptr for this type pair. A cast involving both scalars
+ // and vectors requires and additional bitcast.
+ if (OldTy->getScalarType()->isIntegerTy() &&
+ NewTy->getScalarType()->isPointerTy()) {
+ // Expand <2 x i32> to i8* --> <2 x i32> to i64 to i8*
+ if (OldTy->isVectorTy() && !NewTy->isVectorTy())
+ return IRB.CreateIntToPtr(IRB.CreateBitCast(V, DL.getIntPtrType(NewTy)),
+ NewTy);
+
+ // Expand i128 to <2 x i8*> --> i128 to <2 x i64> to <2 x i8*>
+ if (!OldTy->isVectorTy() && NewTy->isVectorTy())
+ return IRB.CreateIntToPtr(IRB.CreateBitCast(V, DL.getIntPtrType(NewTy)),
+ NewTy);
+
+ return IRB.CreateIntToPtr(V, NewTy);
+ }
+
+ // See if we need ptrtoint for this type pair. A cast involving both scalars
+ // and vectors requires and additional bitcast.
+ if (OldTy->getScalarType()->isPointerTy() &&
+ NewTy->getScalarType()->isIntegerTy()) {
+ // Expand <2 x i8*> to i128 --> <2 x i8*> to <2 x i64> to i128
+ if (OldTy->isVectorTy() && !NewTy->isVectorTy())
+ return IRB.CreateBitCast(IRB.CreatePtrToInt(V, DL.getIntPtrType(OldTy)),
+ NewTy);
+
+ // Expand i8* to <2 x i32> --> i8* to i64 to <2 x i32>
+ if (!OldTy->isVectorTy() && NewTy->isVectorTy())
+ return IRB.CreateBitCast(IRB.CreatePtrToInt(V, DL.getIntPtrType(OldTy)),
+ NewTy);
+
+ return IRB.CreatePtrToInt(V, NewTy);
+ }
+
+ return IRB.CreateBitCast(V, NewTy);
}
/// \brief Test whether the given slice use can be promoted to a vector.
@@ -3364,12 +3430,12 @@ void SROA::deleteDeadInstructions(SmallPtrSet<AllocaInst*, 4> &DeletedAllocas) {
}
static void enqueueUsersInWorklist(Instruction &I,
- SmallVectorImpl<Use *> &UseWorklist,
- SmallPtrSet<Use *, 8> &VisitedUses) {
+ SmallVectorImpl<Instruction *> &Worklist,
+ SmallPtrSet<Instruction *, 8> &Visited) {
for (Value::use_iterator UI = I.use_begin(), UE = I.use_end(); UI != UE;
++UI)
- if (VisitedUses.insert(&UI.getUse()))
- UseWorklist.push_back(&UI.getUse());
+ if (Visited.insert(cast<Instruction>(*UI)))
+ Worklist.push_back(cast<Instruction>(*UI));
}
/// \brief Promote the allocas, using the best available technique.
@@ -3388,7 +3454,7 @@ bool SROA::promoteAllocas(Function &F) {
if (DT && !ForceSSAUpdater) {
DEBUG(dbgs() << "Promoting allocas with mem2reg...\n");
- PromoteMemToReg(PromotableAllocas, *DT, DL);
+ PromoteMemToReg(PromotableAllocas, *DT);
PromotableAllocas.clear();
return true;
}
@@ -3396,29 +3462,29 @@ bool SROA::promoteAllocas(Function &F) {
DEBUG(dbgs() << "Promoting allocas with SSAUpdater...\n");
SSAUpdater SSA;
DIBuilder DIB(*F.getParent());
- SmallVector<Instruction*, 64> Insts;
+ SmallVector<Instruction *, 64> Insts;
// We need a worklist to walk the uses of each alloca.
- SmallVector<Use *, 8> UseWorklist;
- SmallPtrSet<Use *, 8> VisitedUses;
+ SmallVector<Instruction *, 8> Worklist;
+ SmallPtrSet<Instruction *, 8> Visited;
SmallVector<Instruction *, 32> DeadInsts;
for (unsigned Idx = 0, Size = PromotableAllocas.size(); Idx != Size; ++Idx) {
AllocaInst *AI = PromotableAllocas[Idx];
- UseWorklist.clear();
- VisitedUses.clear();
+ Insts.clear();
+ Worklist.clear();
+ Visited.clear();
- enqueueUsersInWorklist(*AI, UseWorklist, VisitedUses);
+ enqueueUsersInWorklist(*AI, Worklist, Visited);
- while (!UseWorklist.empty()) {
- Use *U = UseWorklist.pop_back_val();
- Instruction &I = *cast<Instruction>(U->getUser());
+ while (!Worklist.empty()) {
+ Instruction *I = Worklist.pop_back_val();
// FIXME: Currently the SSAUpdater infrastructure doesn't reason about
// lifetime intrinsics and so we strip them (and the bitcasts+GEPs
// leading to them) here. Eventually it should use them to optimize the
// scalar values produced.
- if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(&I)) {
+ if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(I)) {
assert(II->getIntrinsicID() == Intrinsic::lifetime_start ||
II->getIntrinsicID() == Intrinsic::lifetime_end);
II->eraseFromParent();
@@ -3428,12 +3494,12 @@ bool SROA::promoteAllocas(Function &F) {
// Push the loads and stores we find onto the list. SROA will already
// have validated that all loads and stores are viable candidates for
// promotion.
- if (LoadInst *LI = dyn_cast<LoadInst>(&I)) {
+ if (LoadInst *LI = dyn_cast<LoadInst>(I)) {
assert(LI->getType() == AI->getAllocatedType());
Insts.push_back(LI);
continue;
}
- if (StoreInst *SI = dyn_cast<StoreInst>(&I)) {
+ if (StoreInst *SI = dyn_cast<StoreInst>(I)) {
assert(SI->getValueOperand()->getType() == AI->getAllocatedType());
Insts.push_back(SI);
continue;
@@ -3442,11 +3508,10 @@ bool SROA::promoteAllocas(Function &F) {
// For everything else, we know that only no-op bitcasts and GEPs will
// make it this far, just recurse through them and recall them for later
// removal.
- DeadInsts.push_back(&I);
- enqueueUsersInWorklist(I, UseWorklist, VisitedUses);
+ DeadInsts.push_back(I);
+ enqueueUsersInWorklist(*I, Worklist, Visited);
}
AllocaPromoter(Insts, SSA, *AI, DIB).run(Insts);
- Insts.clear();
while (!DeadInsts.empty())
DeadInsts.pop_back_val()->eraseFromParent();
AI->eraseFromParent();