C++ Operand::get方法代码示例

/// This should be called in top-down order of each def that needs its uses
/// rewrited. The order that we visit uses for a given def is irrelevant.
void SILSSAUpdater::RewriteUse(Operand &Op) {
  // Replicate function_refs to their uses. SILGen can't build phi nodes for
  // them and it would not make much sense anyways.
  if (auto *FR = dyn_cast<FunctionRefInst>(Op.get())) {
    assert(areIdentical(getAvailVals(AV)) &&
           "The function_refs need to have the same value");
    SILInstruction *User = Op.getUser();
    auto *NewFR = FR->clone(User);
    Op.set(SILValue(NewFR, Op.get().getResultNumber()));
    return;
  } else if (auto *IL = dyn_cast<IntegerLiteralInst>(Op.get()))
    if (areIdentical(getAvailVals(AV))) {
      // Some llvm intrinsics don't like phi nodes as their constant inputs (e.g
      // ctlz).
      SILInstruction *User = Op.getUser();
      auto *NewIL = IL->clone(User);
      Op.set(SILValue(NewIL, Op.get().getResultNumber()));
      return;
    }

  // Again we need to be careful here, because ssa construction (with the
  // existing representation) can change the operand from under us.
  UseWrapper UW(&Op);

  SILInstruction *User = Op.getUser();
  SILValue NewVal = GetValueInMiddleOfBlock(User->getParent());
  assert(NewVal && "Need a valid value");
 ((Operand *)UW)->set((SILValue)NewVal);
}

void SILInstruction::replaceAllUsesWithUndef() {
  SILModule &Mod = getModule();
  while (!use_empty()) {
    Operand *Op = *use_begin();
    Op->set(SILUndef::get(Op->get()->getType(), Mod));
  }
}

void ValueBase::replaceAllUsesWith(ValueBase *RHS) {
  assert(this != RHS && "Cannot RAUW a value with itself");
  assert(getNumTypes() == RHS->getNumTypes() &&
         "An instruction and the value base that it is being replaced by "
         "must have the same number of types");

  while (!use_empty()) {
    Operand *Op = *use_begin();
    Op->set(SILValue(RHS, Op->get().getResultNumber()));
  }
}

bool SILValueOwnershipChecker::gatherUsers(
    SmallVectorImpl<BranchPropagatedUser> &lifetimeEndingUsers,
    SmallVectorImpl<BranchPropagatedUser> &nonLifetimeEndingUsers,
    SmallVectorImpl<BranchPropagatedUser> &implicitRegularUsers) {

  // See if Value is guaranteed. If we are guaranteed and not forwarding, then
  // we need to look through subobject uses for more uses. Otherwise, if we are
  // forwarding, we do not create any lifetime ending users/non lifetime ending
  // users since we verify against our base.
  auto ownershipKind = value.getOwnershipKind();
  bool isGuaranteed = ownershipKind == ValueOwnershipKind::Guaranteed;
  bool isOwned = ownershipKind == ValueOwnershipKind::Owned;

  if (isGuaranteed && isGuaranteedForwardingValue(value))
    return true;

  // Then gather up our initial list of users.
  SmallVector<Operand *, 8> users;
  std::copy(value->use_begin(), value->use_end(), std::back_inserter(users));

  auto addCondBranchToList = [](SmallVectorImpl<BranchPropagatedUser> &list,
                                CondBranchInst *cbi, unsigned operandIndex) {
    if (cbi->isConditionOperandIndex(operandIndex)) {
      list.emplace_back(cbi);
      return;
    }

    bool isTrueOperand = cbi->isTrueOperandIndex(operandIndex);
    list.emplace_back(cbi, isTrueOperand ? CondBranchInst::TrueIdx
                                         : CondBranchInst::FalseIdx);
  };

  bool foundError = false;
  while (!users.empty()) {
    Operand *op = users.pop_back_val();
    SILInstruction *user = op->getUser();

    // If this op is a type dependent operand, skip it. It is not interesting
    // from an ownership perspective.
    if (user->isTypeDependentOperand(*op))
      continue;

    bool isGuaranteedSubValue = false;
    if (isGuaranteed && isGuaranteedForwardingInst(op->getUser())) {
      isGuaranteedSubValue = true;
    }

    auto opOwnershipKindMap = op->getOwnershipKindMap(isGuaranteedSubValue);
    // If our ownership kind doesn't match, track that we found an error, emit
    // an error message optionally and then continue.
    if (!opOwnershipKindMap.canAcceptKind(ownershipKind)) {
      foundError = true;

      // If we did not support /any/ ownership kind, it means that we found a
      // conflicting answer so the kind map that was returned is the empty
      // map. Put out a more specific error here.
      if (!opOwnershipKindMap.data.any()) {
        handleError([&]() {
          llvm::errs() << "Function: '" << user->getFunction()->getName()
                       << "'\n"
                       << "Ill-formed SIL! Unable to compute ownership kind "
                          "map for user?!\n"
                       << "For terminator users, check that successors have "
                          "compatible ownership kinds.\n"
                       << "Value: " << op->get() << "User: " << *user
                       << "Operand Number: " << op->getOperandNumber() << '\n'
                       << "Conv: " << ownershipKind << "\n\n";
        });
        continue;
      }

      handleError([&]() {
        llvm::errs() << "Function: '" << user->getFunction()->getName() << "'\n"
                     << "Have operand with incompatible ownership?!\n"
                     << "Value: " << op->get() << "User: " << *user
                     << "Operand Number: " << op->getOperandNumber() << '\n'
                     << "Conv: " << ownershipKind << '\n'
                     << "OwnershipMap:\n"
                     << opOwnershipKindMap << '\n';
      });
      continue;
    }

    auto lifetimeConstraint =
        opOwnershipKindMap.getLifetimeConstraint(ownershipKind);
    if (lifetimeConstraint == UseLifetimeConstraint::MustBeInvalidated) {
      LLVM_DEBUG(llvm::dbgs() << "        Lifetime Ending User: " << *user);
      if (auto *cbi = dyn_cast<CondBranchInst>(user)) {
        addCondBranchToList(lifetimeEndingUsers, cbi, op->getOperandNumber());
      } else {
        lifetimeEndingUsers.emplace_back(user);
      }
    } else {
      LLVM_DEBUG(llvm::dbgs() << "        Regular User: " << *user);
      if (auto *cbi = dyn_cast<CondBranchInst>(user)) {
        addCondBranchToList(nonLifetimeEndingUsers, cbi,
                            op->getOperandNumber());
      } else {
        nonLifetimeEndingUsers.emplace_back(user);
      }
//.........这里部分代码省略.........

void swift::visitAccessedAddress(SILInstruction *I,
                                 llvm::function_ref<void(Operand *)> visitor) {
  assert(I->mayReadOrWriteMemory());

  // Reference counting instructions do not access user visible memory.
  if (isa<RefCountingInst>(I))
    return;

  if (isa<DeallocationInst>(I))
    return;

  if (auto apply = FullApplySite::isa(I)) {
    visitApplyAccesses(apply, visitor);
    return;
  }

  if (auto builtin = dyn_cast<BuiltinInst>(I)) {
    visitBuiltinAddress(builtin, visitor);
    return;
  }

  switch (I->getKind()) {
  default:
    I->dump();
    llvm_unreachable("unexpected memory access.");

  case SILInstructionKind::AssignInst:
    visitor(&I->getAllOperands()[AssignInst::Dest]);
    return;

  case SILInstructionKind::CheckedCastAddrBranchInst:
    visitor(&I->getAllOperands()[CheckedCastAddrBranchInst::Src]);
    visitor(&I->getAllOperands()[CheckedCastAddrBranchInst::Dest]);
    return;

  case SILInstructionKind::CopyAddrInst:
    visitor(&I->getAllOperands()[CopyAddrInst::Src]);
    visitor(&I->getAllOperands()[CopyAddrInst::Dest]);
    return;

#define NEVER_LOADABLE_CHECKED_REF_STORAGE(Name, ...) \
  case SILInstructionKind::Store##Name##Inst:
#define SOMETIMES_LOADABLE_CHECKED_REF_STORAGE(Name, ...) \
  case SILInstructionKind::Store##Name##Inst:
#include "swift/AST/ReferenceStorage.def"
  case SILInstructionKind::StoreInst:
  case SILInstructionKind::StoreBorrowInst:
    visitor(&I->getAllOperands()[StoreInst::Dest]);
    return;

  case SILInstructionKind::SelectEnumAddrInst:
    visitor(&I->getAllOperands()[0]);
    return;

#define NEVER_LOADABLE_CHECKED_REF_STORAGE(Name, ...) \
  case SILInstructionKind::Load##Name##Inst:
#define SOMETIMES_LOADABLE_CHECKED_REF_STORAGE(Name, ...) \
  case SILInstructionKind::Load##Name##Inst:
#include "swift/AST/ReferenceStorage.def"
  case SILInstructionKind::InitExistentialAddrInst:
  case SILInstructionKind::InjectEnumAddrInst:
  case SILInstructionKind::LoadInst:
  case SILInstructionKind::LoadBorrowInst:
  case SILInstructionKind::OpenExistentialAddrInst:
  case SILInstructionKind::SwitchEnumAddrInst:
  case SILInstructionKind::UncheckedTakeEnumDataAddrInst:
  case SILInstructionKind::UnconditionalCheckedCastInst: {
    // Assuming all the above have only a single address operand.
    assert(I->getNumOperands() - I->getNumTypeDependentOperands() == 1);
    Operand *singleOperand = &I->getAllOperands()[0];
    // Check the operand type because UnconditionalCheckedCastInst may operate
    // on a non-address.
    if (singleOperand->get()->getType().isAddress())
      visitor(singleOperand);
    return;
  }
  // Non-access cases: these are marked with memory side effects, but, by
  // themselves, do not access formal memory.
#define SOMETIMES_LOADABLE_CHECKED_REF_STORAGE(Name, ...) \
  case SILInstructionKind::Copy##Name##ValueInst:
#include "swift/AST/ReferenceStorage.def"
  case SILInstructionKind::AbortApplyInst:
  case SILInstructionKind::AllocBoxInst:
  case SILInstructionKind::AllocExistentialBoxInst:
  case SILInstructionKind::AllocGlobalInst:
  case SILInstructionKind::BeginAccessInst:
  case SILInstructionKind::BeginApplyInst:
  case SILInstructionKind::BeginBorrowInst:
  case SILInstructionKind::BeginUnpairedAccessInst:
  case SILInstructionKind::BindMemoryInst:
  case SILInstructionKind::CheckedCastValueBranchInst:
  case SILInstructionKind::CondFailInst:
  case SILInstructionKind::CopyBlockInst:
  case SILInstructionKind::CopyBlockWithoutEscapingInst:
  case SILInstructionKind::CopyValueInst:
  case SILInstructionKind::DeinitExistentialAddrInst:
  case SILInstructionKind::DeinitExistentialValueInst:
  case SILInstructionKind::DestroyAddrInst:
  case SILInstructionKind::DestroyValueInst:
  case SILInstructionKind::EndAccessInst:
//.........这里部分代码省略.........

/// Simplify the following two frontend patterns:
///
///   %payload_addr = init_enum_data_addr %payload_allocation
///   store %payload to %payload_addr
///   inject_enum_addr %payload_allocation, $EnumType.case
///
///   inject_enum_add %nopayload_allocation, $EnumType.case
///
/// for a concrete enum type $EnumType.case to:
///
///   %1 = enum $EnumType, $EnumType.case, %payload
///   store %1 to %payload_addr
///
///   %1 = enum $EnumType, $EnumType.case
///   store %1 to %nopayload_addr
///
/// We leave the cleaning up to mem2reg.
SILInstruction *
SILCombiner::visitInjectEnumAddrInst(InjectEnumAddrInst *IEAI) {
  // Given an inject_enum_addr of a concrete type without payload, promote it to
  // a store of an enum. Mem2reg/load forwarding will clean things up for us. We
  // can't handle the payload case here due to the flow problems caused by the
  // dependency in between the enum and its data.

  assert(IEAI->getOperand()->getType().isAddress() && "Must be an address");
  Builder.setCurrentDebugScope(IEAI->getDebugScope());

  if (IEAI->getOperand()->getType().isAddressOnly(IEAI->getModule())) {
    // Check for the following pattern inside the current basic block:
    // inject_enum_addr %payload_allocation, $EnumType.case1
    // ... no insns storing anything into %payload_allocation
    // select_enum_addr  %payload_allocation,
    //                   case $EnumType.case1: %Result1,
    //                   case case $EnumType.case2: %bResult2
    //                   ...
    //
    // Replace the select_enum_addr by %Result1

    auto *Term = IEAI->getParent()->getTerminator();
    if (isa<CondBranchInst>(Term) || isa<SwitchValueInst>(Term)) {
      auto BeforeTerm = std::prev(std::prev(IEAI->getParent()->end()));
      auto *SEAI = dyn_cast<SelectEnumAddrInst>(BeforeTerm);
      if (!SEAI)
        return nullptr;

      if (SEAI->getOperand() != IEAI->getOperand())
        return nullptr;

      SILBasicBlock::iterator II = IEAI->getIterator();
      StoreInst *SI = nullptr;
      for (;;) {
        SILInstruction *CI = &*II;
        if (CI == SEAI)
          break;
        ++II;
        SI = dyn_cast<StoreInst>(CI);
        if (SI) {
          if (SI->getDest() == IEAI->getOperand())
            return nullptr;
        }
        // Allow all instructions in between, which don't have any dependency to
        // the store.
        if (AA->mayWriteToMemory(&*II, IEAI->getOperand()))
          return nullptr;
      }

      auto *InjectedEnumElement = IEAI->getElement();
      auto Result = SEAI->getCaseResult(InjectedEnumElement);

      // Replace select_enum_addr by the result
      replaceInstUsesWith(*SEAI, Result);
      return nullptr;
    }

    // Check for the following pattern inside the current basic block:
    // inject_enum_addr %payload_allocation, $EnumType.case1
    // ... no insns storing anything into %payload_allocation
    // switch_enum_addr  %payload_allocation,
    //                   case $EnumType.case1: %bbX,
    //                   case case $EnumType.case2: %bbY
    //                   ...
    //
    // Replace the switch_enum_addr by select_enum_addr, switch_value.
    if (auto *SEI = dyn_cast<SwitchEnumAddrInst>(Term)) {
      if (SEI->getOperand() != IEAI->getOperand())
        return nullptr;

      SILBasicBlock::iterator II = IEAI->getIterator();
      StoreInst *SI = nullptr;
      for (;;) {
        SILInstruction *CI = &*II;
        if (CI == SEI)
          break;
        ++II;
        SI = dyn_cast<StoreInst>(CI);
        if (SI) {
          if (SI->getDest() == IEAI->getOperand())
            return nullptr;
        }
        // Allow all instructions in between, which don't have any dependency to
//.........这里部分代码省略.........