[opaque pointer types] Alloca: use getAllocatedType() instead of getType()->getElementType().

[mjacob]

lib/Transforms/Scalar/ScalarReplAggregates.cpp

2237–2238

Are you sure this is right? I don't think we can assume that AI and OtherPtr have the same type.

2254–2255

Why don't you reuse EltPtr?

2487

Why don't you reuse SrcField?

[eddyb]

lib/Transforms/Scalar/ScalarReplAggregates.cpp

2237–2238

OtherPtr is ensured above to have the type PointerType::get(AI->getAllocatedType(), AddrSpace).

2254–2255

Wrong type, NewElts is an array of AllocaInst*, and I believe EltPtr is assigned something that is not an AllocaInst* (or used to, looking again at it doesn't seem to be the case atm).

2487

See previous comment. In this case, SrcField *does* get assigned, so I can't change its type to AllocaInst*.

[dblaikie]

Thanks for all the work/patches posted here. Will be getting to the reviews as quick as I can.

This one looks good, please commit!

lib/Transforms/Scalar/ScalarReplAggregates.cpp

2237–2238

Could throw in an assert to that effect if you like

2254–2255

Feel free to correct the type (since, as you say, it's no longer reused for other things) & reuse it if you like

[eddyb]

Reuse EltPtr variable, with a more precise type.

[eddyb]

Assert that OtherPtr still has the same pointer type as the alloca.

[mjacob]

LGTM.

lib/Analysis/ValueTracking.cpp

case Instruction::URem: {
     KnownZero = APInt::getHighBitsSet(BitWidth, Leaders);
     break;
   }
 
   case Instruction::Alloca: {
     AllocaInst *AI = cast<AllocaInst>(I);
     unsigned Align = AI->getAlignment();
     if (Align == 0)
-      Align = Q.DL.getABITypeAlignment(AI->getType()->getElementType());
+      Align = Q.DL.getABITypeAlignment(AI->getAllocatedType());
 
     if (Align > 0)
       KnownZero = APInt::getLowBitsSet(BitWidth, countTrailingZeros(Align));
     break;
   }
   case Instruction::GetElementPtr: {
     // Analyze all of the subscripts of this getelementptr instruction
     // to determine if we can prove known low zero bits.

lib/CodeGen/GCRootLowering.cpp

if (StoreInst *SI = dyn_cast<StoreInst>(IP))
         InitedRoots.insert(AI);
 
   // Add root initializers.
   bool MadeChange = false;
 
   for (AllocaInst **I = Roots, **E = Roots + Count; I != E; ++I)
     if (!InitedRoots.count(*I)) {
       StoreInst *SI = new StoreInst(
-          ConstantPointerNull::get(cast<PointerType>(
-              cast<PointerType>((*I)->getType())->getElementType())),
+          ConstantPointerNull::get(cast<PointerType>((*I)->getAllocatedType())),
           *I);
       SI->insertAfter(*I);
       MadeChange = true;
     }
 
   return MadeChange;
 }
 

lib/Transforms/IPO/GlobalOpt.cpp

if (StoreInst *SI = dyn_cast<StoreInst>(CurInst)) {
       }
 
       DEBUG(dbgs() << "Evaluated load: " << *InstResult << "\n");
     } else if (AllocaInst *AI = dyn_cast<AllocaInst>(CurInst)) {
       if (AI->isArrayAllocation()) {
         DEBUG(dbgs() << "Found an array alloca. Can not evaluate.\n");
         return false;  // Cannot handle array allocs.
       }
-      Type *Ty = AI->getType()->getElementType();
+      Type *Ty = AI->getAllocatedType();
       AllocaTmps.push_back(
           make_unique<GlobalVariable>(Ty, false, GlobalValue::InternalLinkage,
                                       UndefValue::get(Ty), AI->getName()));
       InstResult = AllocaTmps.back().get();
       DEBUG(dbgs() << "Found an alloca. Result: " << *InstResult << "\n");
     } else if (isa<CallInst>(CurInst) || isa<InvokeInst>(CurInst)) {
       CallSite CS(&*CurInst);
 

lib/Transforms/Scalar/RewriteStatepointsForGC.cpp

if (ClobberNonLive) {
         if (VisitedLiveValues.count(Def)) {
           continue;
         }
         ToClobber.push_back(Alloca);
       }
 
       auto InsertClobbersAt = [&](Instruction *IP) {
         for (auto *AI : ToClobber) {
-          auto AIType = cast<PointerType>(AI->getType());
-          auto PT = cast<PointerType>(AIType->getElementType());
+          auto PT = cast<PointerType>(AI->getAllocatedType());
           Constant *CPN = ConstantPointerNull::get(PT);
           StoreInst *Store = new StoreInst(CPN, AI);
           Store->insertBefore(IP);
         }
       };
 
       // Insert the clobbering stores.  These may get intermixed with the
       // gc.results and gc.relocates, but that's fine.

lib/Transforms/Scalar/ScalarReplAggregates.cpp

if (MemTransferInst *MTI = dyn_cast<MemTransferInst>(User)) {
       if (GetUnderlyingObject(MTI->getSource(), DL, 0) != OrigAI) {
         // Dest must be OrigAI, change this to be a load from the original
         // pointer (bitcasted), then a store to our new alloca.
         assert(MTI->getRawDest() == Ptr && "Neither use is of pointer?");
         Value *SrcPtr = MTI->getSource();
         PointerType* SPTy = cast<PointerType>(SrcPtr->getType());
         PointerType* AIPTy = cast<PointerType>(NewAI->getType());
         if (SPTy->getAddressSpace() != AIPTy->getAddressSpace()) {
-          AIPTy = PointerType::get(AIPTy->getElementType(),
+          AIPTy = PointerType::get(NewAI->getAllocatedType(),
                                    SPTy->getAddressSpace());
         }
         SrcPtr = Builder.CreateBitCast(SrcPtr, AIPTy);
 
         LoadInst *SrcVal = Builder.CreateLoad(SrcPtr, "srcval");
         SrcVal->setAlignment(MTI->getAlignment());
         Builder.CreateStore(SrcVal, NewAI);
       } else if (GetUnderlyingObject(MTI->getDest(), DL, 0) != OrigAI) {
         // Src must be OrigAI, change this to be a load from NewAI then a store
         // through the original dest pointer (bitcasted).
         assert(MTI->getRawSource() == Ptr && "Neither use is of pointer?");
         LoadInst *SrcVal = Builder.CreateLoad(NewAI, "srcval");
 
         PointerType* DPTy = cast<PointerType>(MTI->getDest()->getType());
         PointerType* AIPTy = cast<PointerType>(NewAI->getType());
         if (DPTy->getAddressSpace() != AIPTy->getAddressSpace()) {
-          AIPTy = PointerType::get(AIPTy->getElementType(),
+          AIPTy = PointerType::get(NewAI->getAllocatedType(),
                                    DPTy->getAddressSpace());
         }
         Value *DstPtr = Builder.CreateBitCast(MTI->getDest(), AIPTy);
 
         StoreInst *NewStore = Builder.CreateStore(SrcVal, DstPtr);
         NewStore->setAlignment(MTI->getAlignment());
       } else {
         // Noop transfer. Src == Dst
for (unsigned i = 0, e = InstsToRewrite.size(); i != e; ++i) {
     // Otherwise, we have a PHI node which allows us to push the loads into the
     // predecessors.
     PHINode *PN = cast<PHINode>(InstsToRewrite[i]);
     if (PN->use_empty()) {
       PN->eraseFromParent();
       continue;
     }
 
-    Type *LoadTy = cast<PointerType>(PN->getType())->getElementType();
+    Type *LoadTy = AI->getAllocatedType();
     PHINode *NewPN = PHINode::Create(LoadTy, PN->getNumIncomingValues(),
                                      PN->getName()+".ld", PN);
 
     // Get the AA tags and alignment to use from one of the loads.  It doesn't
     // matter which one we get and if any differ, it doesn't matter.
     LoadInst *SomeLoad = cast<LoadInst>(PN->user_back());
 
     AAMDNodes AATags;
if (OtherPtr == AI || OtherPtr == NewElts[0]) {
              E = DeadInsts.end(); I != E; ++I)
         if (*I == MI) return;
       DeadInsts.push_back(MI);
       return;
     }
 
     // If the pointer is not the right type, insert a bitcast to the right
     // type.
-    Type *NewTy =
-      PointerType::get(AI->getType()->getElementType(), AddrSpace);
+    Type *NewTy = PointerType::get(AI->getAllocatedType(), AddrSpace);
 
     if (OtherPtr->getType() != NewTy)
       OtherPtr = new BitCastInst(OtherPtr, NewTy, OtherPtr->getName(), MI);
   }
 
   // Process each element of the aggregate.
   bool SROADest = MI->getRawDest() == Inst;
 
   Constant *Zero = Constant::getNullValue(Type::getInt32Ty(MI->getContext()));
   const DataLayout &DL = MI->getModule()->getDataLayout();
 
   for (unsigned i = 0, e = NewElts.size(); i != e; ++i) {
     // If this is a memcpy/memmove, emit a GEP of the other element address.
     Value *OtherElt = nullptr;
     unsigned OtherEltAlign = MemAlignment;
 
     if (OtherPtr) {
       Value *Idx[2] = { Zero,
                       ConstantInt::get(Type::getInt32Ty(MI->getContext()), i) };
       OtherElt = GetElementPtrInst::CreateInBounds(OtherPtr, Idx,
                                               OtherPtr->getName()+"."+Twine(i),
                                                    MI);
       uint64_t EltOffset;
-      PointerType *OtherPtrTy = cast<PointerType>(OtherPtr->getType());
-      Type *OtherTy = OtherPtrTy->getElementType();
+      assert(AI->getType() == OtherPtr->getType());
+      Type *OtherTy = AI->getAllocatedType();
       if (StructType *ST = dyn_cast<StructType>(OtherTy)) {
         EltOffset = DL.getStructLayout(ST)->getElementOffset(i);
       } else {
         Type *EltTy = cast<SequentialType>(OtherTy)->getElementType();
         EltOffset = DL.getTypeAllocSize(EltTy) * i;
       }
 
       // The alignment of the other pointer is the guaranteed alignment of the
       // element, which is affected by both the known alignment of the whole
       // mem intrinsic and the alignment of the element.  If the alignment of
       // the memcpy (f.e.) is 32 but the element is at a 4-byte offset, then the
       // known alignment is just 4 bytes.
       OtherEltAlign = (unsigned)MinAlign(OtherEltAlign, EltOffset);
     }
 
-    Value *EltPtr = NewElts[i];
-    Type *EltTy = cast<PointerType>(EltPtr->getType())->getElementType();
+    AllocaInst *EltPtr = NewElts[i];
+    Type *EltTy = EltPtr->getAllocatedType();
 
     // If we got down to a scalar, insert a load or store as appropriate.
     if (EltTy->isSingleValueType()) {
       if (isa<MemTransferInst>(MI)) {
         if (SROADest) {
           // From Other to Alloca.
           Value *Elt = new LoadInst(OtherElt, "tmp", false, OtherEltAlign, MI);
           new StoreInst(Elt, EltPtr, MI);
SROA::RewriteLoadUserOfWholeAlloca(LoadInst *LI, AllocaInst *AI,
 
   Value *ResultVal =
     Constant::getNullValue(IntegerType::get(LI->getContext(), AllocaSizeBits));
 
   for (unsigned i = 0, e = NewElts.size(); i != e; ++i) {
     // Load the value from the alloca.  If the NewElt is an aggregate, cast
     // the pointer to an integer of the same size before doing the load.
     Value *SrcField = NewElts[i];
-    Type *FieldTy =
-      cast<PointerType>(SrcField->getType())->getElementType();
+    Type *FieldTy = NewElts[i]->getAllocatedType();
     uint64_t FieldSizeBits = DL.getTypeSizeInBits(FieldTy);
 
     // Ignore zero sized fields like {}, they obviously contain no data.
     if (FieldSizeBits == 0) continue;
 
     IntegerType *FieldIntTy = IntegerType::get(LI->getContext(),
                                                      FieldSizeBits);
     if (!FieldTy->isIntegerTy() && !FieldTy->isFloatingPointTy() &&