[OpaquePtr] Add type parameter to emitLoadLinked

[kparzysz]

Summary

Add type parameter to TargetLowering::emitLoadLinked.

[nikic]

Is it possible to add a test for this (without running into other crashes)? That is, add a variant using ptr to an existing test for this functionality?

Otherwise this looks good to me.

[kparzysz]

Fixed a couple of missed uses of getElementType.

Added a test for Hexagon. Both ARM and AArch64 were crashing in getTgtMemIntrinsic during DAG construction.

llvm/include/llvm/CodeGen/TargetLowering.h

public:
   virtual bool shouldInsertFencesForAtomic(const Instruction *I) const {
     return false;
   }
 
   /// Perform a load-linked operation on Addr, returning a "Value *" with the
   /// corresponding pointee type. This may entail some non-trivial operations to
   /// truncate or reconstruct types that will be illegal in the backend. See
   /// ARMISelLowering for an example implementation.
-  virtual Value *emitLoadLinked(IRBuilderBase &Builder, Value *Addr,
-                                AtomicOrdering Ord) const {
+  virtual Value *emitLoadLinked(IRBuilderBase &Builder, Type *ValueTy,
+                                Value *Addr, AtomicOrdering Ord) const {
     llvm_unreachable("Load linked unimplemented on this target");
   }
 
   /// Perform a store-conditional operation to Addr. Return the status of the
   /// store. This should be 0 if the store succeeded, non-zero otherwise.
   virtual Value *emitStoreConditional(IRBuilderBase &Builder, Value *Val,
                                       Value *Addr, AtomicOrdering Ord) const {
     llvm_unreachable("Store conditional unimplemented on this target");

llvm/lib/CodeGen/AtomicExpandPass.cpp

 }
 
 bool AtomicExpand::expandAtomicLoadToLL(LoadInst *LI) {
   IRBuilder<> Builder(LI);
 
   // On some architectures, load-linked instructions are atomic for larger
   // sizes than normal loads. For example, the only 64-bit load guaranteed
   // to be single-copy atomic by ARM is an ldrexd (A3.5.3).
-  Value *Val =
-      TLI->emitLoadLinked(Builder, LI->getPointerOperand(), LI->getOrdering());
+  Value *Val = TLI->emitLoadLinked(Builder, LI->getType(),
+                                   LI->getPointerOperand(), LI->getOrdering());
   TLI->emitAtomicCmpXchgNoStoreLLBalance(Builder);
 
   LI->replaceAllUsesWith(Val);
   LI->eraseFromParent();
 
   return true;
 }
 
Value *AtomicExpand::insertRMWLLSCLoop(
   // The split call above "helpfully" added a branch at the end of BB (to the
   // wrong place).
   std::prev(BB->end())->eraseFromParent();
   Builder.SetInsertPoint(BB);
   Builder.CreateBr(LoopBB);
 
   // Start the main loop block now that we've taken care of the preliminaries.
   Builder.SetInsertPoint(LoopBB);
-  Value *Loaded = TLI->emitLoadLinked(Builder, Addr, MemOpOrder);
+  Value *Loaded = TLI->emitLoadLinked(Builder, ResultTy, Addr, MemOpOrder);
 
   Value *NewVal = PerformOp(Builder, Loaded);
 
   Value *StoreSuccess =
       TLI->emitStoreConditional(Builder, NewVal, Addr, MemOpOrder);
   Value *TryAgain = Builder.CreateICmpNE(
       StoreSuccess, ConstantInt::get(IntegerType::get(Ctx, 32), 0), "tryagain");
   Builder.CreateCondBr(TryAgain, LoopBB, ExitBB);
bool AtomicExpand::expandAtomicCmpXchg(AtomicCmpXchgInst *CI) {
   PartwordMaskValues PMV =
       createMaskInstrs(Builder, CI, CI->getCompareOperand()->getType(), Addr,
                        CI->getAlign(), TLI->getMinCmpXchgSizeInBits() / 8);
   Builder.CreateBr(StartBB);
 
   // Start the main loop block now that we've taken care of the preliminaries.
   Builder.SetInsertPoint(StartBB);
   Value *UnreleasedLoad =
-      TLI->emitLoadLinked(Builder, PMV.AlignedAddr, MemOpOrder);
+      TLI->emitLoadLinked(Builder, PMV.WordType, PMV.AlignedAddr, MemOpOrder);
   Value *UnreleasedLoadExtract =
       extractMaskedValue(Builder, UnreleasedLoad, PMV);
   Value *ShouldStore = Builder.CreateICmpEQ(
       UnreleasedLoadExtract, CI->getCompareOperand(), "should_store");
 
   // If the cmpxchg doesn't actually need any ordering when it fails, we can
   // jump straight past that fence instruction (if it exists).
   Builder.CreateCondBr(ShouldStore, ReleasingStoreBB, NoStoreBB);
StoreSuccess = Builder.CreateICmpEQ(
       StoreSuccess, ConstantInt::get(Type::getInt32Ty(Ctx), 0), "success");
   BasicBlock *RetryBB = HasReleasedLoadBB ? ReleasedLoadBB : StartBB;
   Builder.CreateCondBr(StoreSuccess, SuccessBB,
                        CI->isWeak() ? FailureBB : RetryBB);
 
   Builder.SetInsertPoint(ReleasedLoadBB);
   Value *SecondLoad;
   if (HasReleasedLoadBB) {
-    SecondLoad = TLI->emitLoadLinked(Builder, PMV.AlignedAddr, MemOpOrder);
+    SecondLoad =
+        TLI->emitLoadLinked(Builder, PMV.WordType, PMV.AlignedAddr, MemOpOrder);
     Value *SecondLoadExtract = extractMaskedValue(Builder, SecondLoad, PMV);
     ShouldStore = Builder.CreateICmpEQ(SecondLoadExtract,
                                        CI->getCompareOperand(), "should_store");
 
     // If the cmpxchg doesn't actually need any ordering when it fails, we can
     // jump straight past that fence instruction (if it exists).
     Builder.CreateCondBr(ShouldStore, TryStoreBB, NoStoreBB);
     // Update PHI node in TryStoreBB.

llvm/lib/Target/AArch64/AArch64ISelLowering.h

public:
 
   bool shouldFormOverflowOp(unsigned Opcode, EVT VT,
                             bool MathUsed) const override {
     // Using overflow ops for overflow checks only should beneficial on
     // AArch64.
     return TargetLowering::shouldFormOverflowOp(Opcode, VT, true);
   }
 
-  Value *emitLoadLinked(IRBuilderBase &Builder, Value *Addr,
+  Value *emitLoadLinked(IRBuilderBase &Builder, Type *ValueTy, Value *Addr,
                         AtomicOrdering Ord) const override;
   Value *emitStoreConditional(IRBuilderBase &Builder, Value *Val, Value *Addr,
                               AtomicOrdering Ord) const override;
 
   void emitAtomicCmpXchgNoStoreLLBalance(IRBuilderBase &Builder) const override;
 
   TargetLoweringBase::AtomicExpansionKind
   shouldExpandAtomicLoadInIR(LoadInst *LI) const override;

llvm/lib/Target/AArch64/AArch64ISelLowering.cpp

AArch64TargetLowering::shouldExpandAtomicCmpXchgInIR(
   // situation where the monitor always gets cleared and the atomic operation
   // can never succeed. So at -O0 we need a late-expanded pseudo-inst instead.
   if (getTargetMachine().getOptLevel() == CodeGenOpt::None)
     return AtomicExpansionKind::None;
   return AtomicExpansionKind::LLSC;
 }
 
 Value *AArch64TargetLowering::emitLoadLinked(IRBuilderBase &Builder,
-                                             Value *Addr,
+                                             Type *ValueTy, Value *Addr,
                                              AtomicOrdering Ord) const {
   Module *M = Builder.GetInsertBlock()->getParent()->getParent();
-  Type *ValTy = cast<PointerType>(Addr->getType())->getElementType();
   bool IsAcquire = isAcquireOrStronger(Ord);
 
   // Since i128 isn't legal and intrinsics don't get type-lowered, the ldrexd
   // intrinsic must return {i64, i64} and we have to recombine them into a
   // single i128 here.
-  if (ValTy->getPrimitiveSizeInBits() == 128) {
+  if (ValueTy->getPrimitiveSizeInBits() == 128) {
     Intrinsic::ID Int =
         IsAcquire ? Intrinsic::aarch64_ldaxp : Intrinsic::aarch64_ldxp;
     Function *Ldxr = Intrinsic::getDeclaration(M, Int);
 
     Addr = Builder.CreateBitCast(Addr, Type::getInt8PtrTy(M->getContext()));
     Value *LoHi = Builder.CreateCall(Ldxr, Addr, "lohi");
 
     Value *Lo = Builder.CreateExtractValue(LoHi, 0, "lo");
     Value *Hi = Builder.CreateExtractValue(LoHi, 1, "hi");
-    Lo = Builder.CreateZExt(Lo, ValTy, "lo64");
-    Hi = Builder.CreateZExt(Hi, ValTy, "hi64");
+    Lo = Builder.CreateZExt(Lo, ValueTy, "lo64");
+    Hi = Builder.CreateZExt(Hi, ValueTy, "hi64");
     return Builder.CreateOr(
-        Lo, Builder.CreateShl(Hi, ConstantInt::get(ValTy, 64)), "val64");
+        Lo, Builder.CreateShl(Hi, ConstantInt::get(ValueTy, 64)), "val64");
   }
 
   Type *Tys[] = { Addr->getType() };
   Intrinsic::ID Int =
       IsAcquire ? Intrinsic::aarch64_ldaxr : Intrinsic::aarch64_ldxr;
   Function *Ldxr = Intrinsic::getDeclaration(M, Int, Tys);
 
   Type *EltTy = cast<PointerType>(Addr->getType())->getElementType();

llvm/lib/Target/ARM/ARMISelLowering.h

public:
     getExceptionPointerRegister(const Constant *PersonalityFn) const override;
 
     /// If a physical register, this returns the register that receives the
     /// exception typeid on entry to a landing pad.
     Register
     getExceptionSelectorRegister(const Constant *PersonalityFn) const override;
 
     Instruction *makeDMB(IRBuilderBase &Builder, ARM_MB::MemBOpt Domain) const;
-    Value *emitLoadLinked(IRBuilderBase &Builder, Value *Addr,
+    Value *emitLoadLinked(IRBuilderBase &Builder, Type *ValueTy, Value *Addr,
                           AtomicOrdering Ord) const override;
     Value *emitStoreConditional(IRBuilderBase &Builder, Value *Val, Value *Addr,
                                 AtomicOrdering Ord) const override;
 
     void
     emitAtomicCmpXchgNoStoreLLBalance(IRBuilderBase &Builder) const override;
 
     Instruction *emitLeadingFence(IRBuilderBase &Builder, Instruction *Inst,

llvm/lib/Target/ARM/ARMISelLowering.cpp

 bool ARMTargetLowering::isCheapToSpeculateCtlz() const {
   return Subtarget->hasV6T2Ops();
 }
 
 bool ARMTargetLowering::shouldExpandShift(SelectionDAG &DAG, SDNode *N) const {
   return !Subtarget->hasMinSize() || Subtarget->isTargetWindows();
 }
 
-Value *ARMTargetLowering::emitLoadLinked(IRBuilderBase &Builder, Value *Addr,
+Value *ARMTargetLowering::emitLoadLinked(IRBuilderBase &Builder, Type *ValueTy,
+                                         Value *Addr,
                                          AtomicOrdering Ord) const {
   Module *M = Builder.GetInsertBlock()->getParent()->getParent();
-  Type *ValTy = cast<PointerType>(Addr->getType())->getElementType();
   bool IsAcquire = isAcquireOrStronger(Ord);
 
   // Since i64 isn't legal and intrinsics don't get type-lowered, the ldrexd
   // intrinsic must return {i32, i32} and we have to recombine them into a
   // single i64 here.
-  if (ValTy->getPrimitiveSizeInBits() == 64) {
+  if (ValueTy->getPrimitiveSizeInBits() == 64) {
     Intrinsic::ID Int =
         IsAcquire ? Intrinsic::arm_ldaexd : Intrinsic::arm_ldrexd;
     Function *Ldrex = Intrinsic::getDeclaration(M, Int);
 
     Addr = Builder.CreateBitCast(Addr, Type::getInt8PtrTy(M->getContext()));
     Value *LoHi = Builder.CreateCall(Ldrex, Addr, "lohi");
 
     Value *Lo = Builder.CreateExtractValue(LoHi, 0, "lo");
     Value *Hi = Builder.CreateExtractValue(LoHi, 1, "hi");
     if (!Subtarget->isLittle())
       std::swap (Lo, Hi);
-    Lo = Builder.CreateZExt(Lo, ValTy, "lo64");
-    Hi = Builder.CreateZExt(Hi, ValTy, "hi64");
+    Lo = Builder.CreateZExt(Lo, ValueTy, "lo64");
+    Hi = Builder.CreateZExt(Hi, ValueTy, "hi64");
     return Builder.CreateOr(
-        Lo, Builder.CreateShl(Hi, ConstantInt::get(ValTy, 32)), "val64");
+        Lo, Builder.CreateShl(Hi, ConstantInt::get(ValueTy, 32)), "val64");
   }
 
   Type *Tys[] = { Addr->getType() };
   Intrinsic::ID Int = IsAcquire ? Intrinsic::arm_ldaex : Intrinsic::arm_ldrex;
   Function *Ldrex = Intrinsic::getDeclaration(M, Int, Tys);
 
   return Builder.CreateTruncOrBitCast(
       Builder.CreateCall(Ldrex, Addr),

llvm/lib/Target/Hexagon/HexagonISelLowering.h

public:
   /// Returns relocation base for the given PIC jumptable.
   SDValue getPICJumpTableRelocBase(SDValue Table, SelectionDAG &DAG)
                                    const override;
 
   bool shouldReduceLoadWidth(SDNode *Load, ISD::LoadExtType ExtTy,
                              EVT NewVT) const override;
 
   // Handling of atomic RMW instructions.
-  Value *emitLoadLinked(IRBuilderBase &Builder, Value *Addr,
+  Value *emitLoadLinked(IRBuilderBase &Builder, Type *ValueTy, Value *Addr,
                         AtomicOrdering Ord) const override;
   Value *emitStoreConditional(IRBuilderBase &Builder, Value *Val, Value *Addr,
                               AtomicOrdering Ord) const override;
   AtomicExpansionKind shouldExpandAtomicLoadInIR(LoadInst *LI) const override;
   bool shouldExpandAtomicStoreInIR(StoreInst *SI) const override;
   AtomicExpansionKind
   shouldExpandAtomicCmpXchgInIR(AtomicCmpXchgInst *AI) const override;
 

llvm/lib/Target/Hexagon/HexagonISelLowering.cpp

if (GlobalAddressSDNode *GA = dyn_cast<GlobalAddressSDNode>(BO.first)) {
     auto &HTM = static_cast<const HexagonTargetMachine&>(getTargetMachine());
     const auto *GO = dyn_cast_or_null<const GlobalObject>(GA->getGlobal());
     return !GO || !HTM.getObjFileLowering()->isGlobalInSmallSection(GO, HTM);
   }
   return true;
 }
 
 Value *HexagonTargetLowering::emitLoadLinked(IRBuilderBase &Builder,
-                                             Value *Addr,
+                                             Type *ValueTy, Value *Addr,
                                              AtomicOrdering Ord) const {
   BasicBlock *BB = Builder.GetInsertBlock();
   Module *M = BB->getParent()->getParent();
-  auto PT = cast<PointerType>(Addr->getType());
-  Type *Ty = PT->getElementType();
-  unsigned SZ = Ty->getPrimitiveSizeInBits();
+  unsigned SZ = ValueTy->getPrimitiveSizeInBits();
   assert((SZ == 32 || SZ == 64) && "Only 32/64-bit atomic loads supported");
   Intrinsic::ID IntID = (SZ == 32) ? Intrinsic::hexagon_L2_loadw_locked
                                    : Intrinsic::hexagon_L4_loadd_locked;
   Function *Fn = Intrinsic::getDeclaration(M, IntID);
 
-  PointerType *NewPtrTy
-    = Builder.getIntNTy(SZ)->getPointerTo(PT->getAddressSpace());
+  auto PtrTy = cast<PointerType>(Addr->getType());
+  PointerType *NewPtrTy =
+      Builder.getIntNTy(SZ)->getPointerTo(PtrTy->getAddressSpace());
   Addr = Builder.CreateBitCast(Addr, NewPtrTy);
 
   Value *Call = Builder.CreateCall(Fn, Addr, "larx");
 
-  return Builder.CreateBitCast(Call, Ty);
+  return Builder.CreateBitCast(Call, ValueTy);
 }
 
 /// Perform a store-conditional operation to Addr. Return the status of the
 /// store. This should be 0 if the store succeeded, non-zero otherwise.
 Value *HexagonTargetLowering::emitStoreConditional(IRBuilderBase &Builder,
                                                    Value *Val, Value *Addr,
                                                    AtomicOrdering Ord) const {
   BasicBlock *BB = Builder.GetInsertBlock();