llvm-project/flang/lib/Lower/CallInterface.cpp

1215 lines
52 KiB
C++

//===-- CallInterface.cpp -- Procedure call interface ---------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "flang/Lower/CallInterface.h"
#include "flang/Evaluate/fold.h"
#include "flang/Lower/Bridge.h"
#include "flang/Lower/Mangler.h"
#include "flang/Lower/PFTBuilder.h"
#include "flang/Lower/StatementContext.h"
#include "flang/Lower/Support/Utils.h"
#include "flang/Lower/Todo.h"
#include "flang/Optimizer/Builder/Character.h"
#include "flang/Optimizer/Builder/FIRBuilder.h"
#include "flang/Optimizer/Dialect/FIRDialect.h"
#include "flang/Optimizer/Dialect/FIROpsSupport.h"
#include "flang/Optimizer/Support/InternalNames.h"
#include "flang/Semantics/symbol.h"
#include "flang/Semantics/tools.h"
//===----------------------------------------------------------------------===//
// BIND(C) mangling helpers
//===----------------------------------------------------------------------===//
// Return the binding label (from BIND(C...)) or the mangled name of a symbol.
static std::string getMangledName(const Fortran::semantics::Symbol &symbol) {
const std::string *bindName = symbol.GetBindName();
return bindName ? *bindName : Fortran::lower::mangle::mangleName(symbol);
}
/// Return the type of a dummy procedure given its characteristic (if it has
/// one).
mlir::Type getProcedureDesignatorType(
const Fortran::evaluate::characteristics::Procedure *,
Fortran::lower::AbstractConverter &converter) {
// TODO: Get actual function type of the dummy procedure, at least when an
// interface is given. The result type should be available even if the arity
// and type of the arguments is not.
llvm::SmallVector<mlir::Type> resultTys;
llvm::SmallVector<mlir::Type> inputTys;
// In general, that is a nice to have but we cannot guarantee to find the
// function type that will match the one of the calls, we may not even know
// how many arguments the dummy procedure accepts (e.g. if a procedure
// pointer is only transiting through the current procedure without being
// called), so a function type cast must always be inserted.
auto *context = &converter.getMLIRContext();
auto untypedFunc = mlir::FunctionType::get(context, inputTys, resultTys);
return fir::BoxProcType::get(context, untypedFunc);
}
//===----------------------------------------------------------------------===//
// Caller side interface implementation
//===----------------------------------------------------------------------===//
bool Fortran::lower::CallerInterface::hasAlternateReturns() const {
return procRef.hasAlternateReturns();
}
std::string Fortran::lower::CallerInterface::getMangledName() const {
const Fortran::evaluate::ProcedureDesignator &proc = procRef.proc();
if (const Fortran::semantics::Symbol *symbol = proc.GetSymbol())
return ::getMangledName(symbol->GetUltimate());
assert(proc.GetSpecificIntrinsic() &&
"expected intrinsic procedure in designator");
return proc.GetName();
}
const Fortran::semantics::Symbol *
Fortran::lower::CallerInterface::getProcedureSymbol() const {
return procRef.proc().GetSymbol();
}
bool Fortran::lower::CallerInterface::isIndirectCall() const {
if (const Fortran::semantics::Symbol *symbol = procRef.proc().GetSymbol())
return Fortran::semantics::IsPointer(*symbol) ||
Fortran::semantics::IsDummy(*symbol);
return false;
}
const Fortran::semantics::Symbol *
Fortran::lower::CallerInterface::getIfIndirectCallSymbol() const {
if (const Fortran::semantics::Symbol *symbol = procRef.proc().GetSymbol())
if (Fortran::semantics::IsPointer(*symbol) ||
Fortran::semantics::IsDummy(*symbol))
return symbol;
return nullptr;
}
mlir::Location Fortran::lower::CallerInterface::getCalleeLocation() const {
const Fortran::evaluate::ProcedureDesignator &proc = procRef.proc();
// FIXME: If the callee is defined in the same file but after the current
// unit we cannot get its location here and the funcOp is created at the
// wrong location (i.e, the caller location).
if (const Fortran::semantics::Symbol *symbol = proc.GetSymbol())
return converter.genLocation(symbol->name());
// Use current location for intrinsics.
return converter.getCurrentLocation();
}
// Get dummy argument characteristic for a procedure with implicit interface
// from the actual argument characteristic. The actual argument may not be a F77
// entity. The attribute must be dropped and the shape, if any, must be made
// explicit.
static Fortran::evaluate::characteristics::DummyDataObject
asImplicitArg(Fortran::evaluate::characteristics::DummyDataObject &&dummy) {
Fortran::evaluate::Shape shape =
dummy.type.attrs().none() ? dummy.type.shape()
: Fortran::evaluate::Shape(dummy.type.Rank());
return Fortran::evaluate::characteristics::DummyDataObject(
Fortran::evaluate::characteristics::TypeAndShape(dummy.type.type(),
std::move(shape)));
}
static Fortran::evaluate::characteristics::DummyArgument
asImplicitArg(Fortran::evaluate::characteristics::DummyArgument &&dummy) {
return std::visit(
Fortran::common::visitors{
[&](Fortran::evaluate::characteristics::DummyDataObject &obj) {
return Fortran::evaluate::characteristics::DummyArgument(
std::move(dummy.name), asImplicitArg(std::move(obj)));
},
[&](Fortran::evaluate::characteristics::DummyProcedure &proc) {
return Fortran::evaluate::characteristics::DummyArgument(
std::move(dummy.name), std::move(proc));
},
[](Fortran::evaluate::characteristics::AlternateReturn &x) {
return Fortran::evaluate::characteristics::DummyArgument(
std::move(x));
}},
dummy.u);
}
Fortran::evaluate::characteristics::Procedure
Fortran::lower::CallerInterface::characterize() const {
Fortran::evaluate::FoldingContext &foldingContext =
converter.getFoldingContext();
std::optional<Fortran::evaluate::characteristics::Procedure> characteristic =
Fortran::evaluate::characteristics::Procedure::Characterize(
procRef.proc(), foldingContext);
assert(characteristic && "Failed to get characteristic from procRef");
// The characteristic may not contain the argument characteristic if the
// ProcedureDesignator has no interface.
if (!characteristic->HasExplicitInterface()) {
for (const std::optional<Fortran::evaluate::ActualArgument> &arg :
procRef.arguments()) {
if (arg.value().isAlternateReturn()) {
characteristic->dummyArguments.emplace_back(
Fortran::evaluate::characteristics::AlternateReturn{});
} else {
// Argument cannot be optional with implicit interface
const Fortran::lower::SomeExpr *expr = arg.value().UnwrapExpr();
assert(
expr &&
"argument in call with implicit interface cannot be assumed type");
std::optional<Fortran::evaluate::characteristics::DummyArgument>
argCharacteristic =
Fortran::evaluate::characteristics::DummyArgument::FromActual(
"actual", *expr, foldingContext);
assert(argCharacteristic &&
"failed to characterize argument in implicit call");
characteristic->dummyArguments.emplace_back(
asImplicitArg(std::move(*argCharacteristic)));
}
}
}
return *characteristic;
}
void Fortran::lower::CallerInterface::placeInput(
const PassedEntity &passedEntity, mlir::Value arg) {
assert(static_cast<int>(actualInputs.size()) > passedEntity.firArgument &&
passedEntity.firArgument >= 0 &&
passedEntity.passBy != CallInterface::PassEntityBy::AddressAndLength &&
"bad arg position");
actualInputs[passedEntity.firArgument] = arg;
}
void Fortran::lower::CallerInterface::placeAddressAndLengthInput(
const PassedEntity &passedEntity, mlir::Value addr, mlir::Value len) {
assert(static_cast<int>(actualInputs.size()) > passedEntity.firArgument &&
static_cast<int>(actualInputs.size()) > passedEntity.firLength &&
passedEntity.firArgument >= 0 && passedEntity.firLength >= 0 &&
passedEntity.passBy == CallInterface::PassEntityBy::AddressAndLength &&
"bad arg position");
actualInputs[passedEntity.firArgument] = addr;
actualInputs[passedEntity.firLength] = len;
}
bool Fortran::lower::CallerInterface::verifyActualInputs() const {
if (getNumFIRArguments() != actualInputs.size())
return false;
for (mlir::Value arg : actualInputs) {
if (!arg)
return false;
}
return true;
}
void Fortran::lower::CallerInterface::walkResultLengths(
ExprVisitor visitor) const {
assert(characteristic && "characteristic was not computed");
const Fortran::evaluate::characteristics::FunctionResult &result =
characteristic->functionResult.value();
const Fortran::evaluate::characteristics::TypeAndShape *typeAndShape =
result.GetTypeAndShape();
assert(typeAndShape && "no result type");
Fortran::evaluate::DynamicType dynamicType = typeAndShape->type();
// Visit result length specification expressions that are explicit.
if (dynamicType.category() == Fortran::common::TypeCategory::Character) {
if (std::optional<Fortran::evaluate::ExtentExpr> length =
dynamicType.GetCharLength())
visitor(toEvExpr(*length));
} else if (dynamicType.category() == common::TypeCategory::Derived) {
const Fortran::semantics::DerivedTypeSpec &derivedTypeSpec =
dynamicType.GetDerivedTypeSpec();
if (Fortran::semantics::CountLenParameters(derivedTypeSpec) > 0)
TODO(converter.getCurrentLocation(),
"function result with derived type length parameters");
}
}
// Compute extent expr from shapeSpec of an explicit shape.
// TODO: Allow evaluate shape analysis to work in a mode where it disregards
// the non-constant aspects when building the shape to avoid having this here.
static Fortran::evaluate::ExtentExpr
getExtentExpr(const Fortran::semantics::ShapeSpec &shapeSpec) {
const auto &ubound = shapeSpec.ubound().GetExplicit();
const auto &lbound = shapeSpec.lbound().GetExplicit();
assert(lbound && ubound && "shape must be explicit");
return Fortran::common::Clone(*ubound) - Fortran::common::Clone(*lbound) +
Fortran::evaluate::ExtentExpr{1};
}
void Fortran::lower::CallerInterface::walkResultExtents(
ExprVisitor visitor) const {
// Walk directly the result symbol shape (the characteristic shape may contain
// descriptor inquiries to it that would fail to lower on the caller side).
const Fortran::semantics::Symbol *interfaceSymbol =
procRef.proc().GetInterfaceSymbol();
if (interfaceSymbol) {
const Fortran::semantics::Symbol &result =
interfaceSymbol->get<Fortran::semantics::SubprogramDetails>().result();
if (const auto *objectDetails =
result.detailsIf<Fortran::semantics::ObjectEntityDetails>())
if (objectDetails->shape().IsExplicitShape())
for (const Fortran::semantics::ShapeSpec &shapeSpec :
objectDetails->shape())
visitor(Fortran::evaluate::AsGenericExpr(getExtentExpr(shapeSpec)));
} else {
if (procRef.Rank() != 0)
fir::emitFatalError(
converter.getCurrentLocation(),
"only scalar functions may not have an interface symbol");
}
}
bool Fortran::lower::CallerInterface::mustMapInterfaceSymbols() const {
assert(characteristic && "characteristic was not computed");
const std::optional<Fortran::evaluate::characteristics::FunctionResult>
&result = characteristic->functionResult;
if (!result || result->CanBeReturnedViaImplicitInterface() ||
!procRef.proc().GetInterfaceSymbol())
return false;
bool allResultSpecExprConstant = true;
auto visitor = [&](const Fortran::lower::SomeExpr &e) {
allResultSpecExprConstant &= Fortran::evaluate::IsConstantExpr(e);
};
walkResultLengths(visitor);
walkResultExtents(visitor);
return !allResultSpecExprConstant;
}
mlir::Value Fortran::lower::CallerInterface::getArgumentValue(
const semantics::Symbol &sym) const {
mlir::Location loc = converter.getCurrentLocation();
const Fortran::semantics::Symbol *iface = procRef.proc().GetInterfaceSymbol();
if (!iface)
fir::emitFatalError(
loc, "mapping actual and dummy arguments requires an interface");
const std::vector<Fortran::semantics::Symbol *> &dummies =
iface->get<semantics::SubprogramDetails>().dummyArgs();
auto it = std::find(dummies.begin(), dummies.end(), &sym);
if (it == dummies.end())
fir::emitFatalError(loc, "symbol is not a dummy in this call");
FirValue mlirArgIndex = passedArguments[it - dummies.begin()].firArgument;
return actualInputs[mlirArgIndex];
}
mlir::Type Fortran::lower::CallerInterface::getResultStorageType() const {
if (passedResult)
return fir::dyn_cast_ptrEleTy(inputs[passedResult->firArgument].type);
assert(saveResult && !outputs.empty());
return outputs[0].type;
}
const Fortran::semantics::Symbol &
Fortran::lower::CallerInterface::getResultSymbol() const {
mlir::Location loc = converter.getCurrentLocation();
const Fortran::semantics::Symbol *iface = procRef.proc().GetInterfaceSymbol();
if (!iface)
fir::emitFatalError(
loc, "mapping actual and dummy arguments requires an interface");
return iface->get<semantics::SubprogramDetails>().result();
}
//===----------------------------------------------------------------------===//
// Callee side interface implementation
//===----------------------------------------------------------------------===//
bool Fortran::lower::CalleeInterface::hasAlternateReturns() const {
return !funit.isMainProgram() &&
Fortran::semantics::HasAlternateReturns(funit.getSubprogramSymbol());
}
std::string Fortran::lower::CalleeInterface::getMangledName() const {
if (funit.isMainProgram())
return fir::NameUniquer::doProgramEntry().str();
return ::getMangledName(funit.getSubprogramSymbol());
}
const Fortran::semantics::Symbol *
Fortran::lower::CalleeInterface::getProcedureSymbol() const {
if (funit.isMainProgram())
return nullptr;
return &funit.getSubprogramSymbol();
}
mlir::Location Fortran::lower::CalleeInterface::getCalleeLocation() const {
// FIXME: do NOT use unknown for the anonymous PROGRAM case. We probably
// should just stash the location in the funit regardless.
return converter.genLocation(funit.getStartingSourceLoc());
}
Fortran::evaluate::characteristics::Procedure
Fortran::lower::CalleeInterface::characterize() const {
Fortran::evaluate::FoldingContext &foldingContext =
converter.getFoldingContext();
std::optional<Fortran::evaluate::characteristics::Procedure> characteristic =
Fortran::evaluate::characteristics::Procedure::Characterize(
funit.getSubprogramSymbol(), foldingContext);
assert(characteristic && "Fail to get characteristic from symbol");
return *characteristic;
}
bool Fortran::lower::CalleeInterface::isMainProgram() const {
return funit.isMainProgram();
}
mlir::FuncOp Fortran::lower::CalleeInterface::addEntryBlockAndMapArguments() {
// On the callee side, directly map the mlir::value argument of
// the function block to the Fortran symbols.
func.addEntryBlock();
mapPassedEntities();
return func;
}
bool Fortran::lower::CalleeInterface::hasHostAssociated() const {
return funit.parentHasHostAssoc();
}
mlir::Type Fortran::lower::CalleeInterface::getHostAssociatedTy() const {
assert(hasHostAssociated());
return funit.parentHostAssoc().getArgumentType(converter);
}
mlir::Value Fortran::lower::CalleeInterface::getHostAssociatedTuple() const {
assert(hasHostAssociated() || !funit.getHostAssoc().empty());
return converter.hostAssocTupleValue();
}
//===----------------------------------------------------------------------===//
// CallInterface implementation: this part is common to both caller and caller
// sides.
//===----------------------------------------------------------------------===//
static void addSymbolAttribute(mlir::FuncOp func,
const Fortran::semantics::Symbol &sym,
mlir::MLIRContext &mlirContext) {
// Only add this on bind(C) functions for which the symbol is not reflected in
// the current context.
if (!Fortran::semantics::IsBindCProcedure(sym))
return;
std::string name =
Fortran::lower::mangle::mangleName(sym, /*keepExternalInScope=*/true);
func->setAttr(fir::getSymbolAttrName(),
mlir::StringAttr::get(&mlirContext, name));
}
/// Declare drives the different actions to be performed while analyzing the
/// signature and building/finding the mlir::FuncOp.
template <typename T>
void Fortran::lower::CallInterface<T>::declare() {
if (!side().isMainProgram()) {
characteristic.emplace(side().characterize());
bool isImplicit = characteristic->CanBeCalledViaImplicitInterface();
determineInterface(isImplicit, *characteristic);
}
// No input/output for main program
// Create / get funcOp for direct calls. For indirect calls (only meaningful
// on the caller side), no funcOp has to be created here. The mlir::Value
// holding the indirection is used when creating the fir::CallOp.
if (!side().isIndirectCall()) {
std::string name = side().getMangledName();
mlir::ModuleOp module = converter.getModuleOp();
func = fir::FirOpBuilder::getNamedFunction(module, name);
if (!func) {
mlir::Location loc = side().getCalleeLocation();
mlir::FunctionType ty = genFunctionType();
func = fir::FirOpBuilder::createFunction(loc, module, name, ty);
if (const Fortran::semantics::Symbol *sym = side().getProcedureSymbol())
addSymbolAttribute(func, *sym, converter.getMLIRContext());
for (const auto &placeHolder : llvm::enumerate(inputs))
if (!placeHolder.value().attributes.empty())
func.setArgAttrs(placeHolder.index(), placeHolder.value().attributes);
}
}
}
/// Once the signature has been analyzed and the mlir::FuncOp was built/found,
/// map the fir inputs to Fortran entities (the symbols or expressions).
template <typename T>
void Fortran::lower::CallInterface<T>::mapPassedEntities() {
// map back fir inputs to passed entities
if constexpr (std::is_same_v<T, Fortran::lower::CalleeInterface>) {
assert(inputs.size() == func.front().getArguments().size() &&
"function previously created with different number of arguments");
for (auto [fst, snd] : llvm::zip(inputs, func.front().getArguments()))
mapBackInputToPassedEntity(fst, snd);
} else {
// On the caller side, map the index of the mlir argument position
// to Fortran ActualArguments.
int firPosition = 0;
for (const FirPlaceHolder &placeHolder : inputs)
mapBackInputToPassedEntity(placeHolder, firPosition++);
}
}
template <typename T>
void Fortran::lower::CallInterface<T>::mapBackInputToPassedEntity(
const FirPlaceHolder &placeHolder, FirValue firValue) {
PassedEntity &passedEntity =
placeHolder.passedEntityPosition == FirPlaceHolder::resultEntityPosition
? passedResult.value()
: passedArguments[placeHolder.passedEntityPosition];
if (placeHolder.property == Property::CharLength)
passedEntity.firLength = firValue;
else
passedEntity.firArgument = firValue;
}
/// Helpers to access ActualArgument/Symbols
static const Fortran::evaluate::ActualArguments &
getEntityContainer(const Fortran::evaluate::ProcedureRef &proc) {
return proc.arguments();
}
static const std::vector<Fortran::semantics::Symbol *> &
getEntityContainer(Fortran::lower::pft::FunctionLikeUnit &funit) {
return funit.getSubprogramSymbol()
.get<Fortran::semantics::SubprogramDetails>()
.dummyArgs();
}
static const Fortran::evaluate::ActualArgument *getDataObjectEntity(
const std::optional<Fortran::evaluate::ActualArgument> &arg) {
if (arg)
return &*arg;
return nullptr;
}
static const Fortran::semantics::Symbol &
getDataObjectEntity(const Fortran::semantics::Symbol *arg) {
assert(arg && "expect symbol for data object entity");
return *arg;
}
static const Fortran::evaluate::ActualArgument *
getResultEntity(const Fortran::evaluate::ProcedureRef &) {
return nullptr;
}
static const Fortran::semantics::Symbol &
getResultEntity(Fortran::lower::pft::FunctionLikeUnit &funit) {
return funit.getSubprogramSymbol()
.get<Fortran::semantics::SubprogramDetails>()
.result();
}
/// Bypass helpers to manipulate entities since they are not any symbol/actual
/// argument to associate. See SignatureBuilder below.
using FakeEntity = bool;
using FakeEntities = llvm::SmallVector<FakeEntity>;
static FakeEntities
getEntityContainer(const Fortran::evaluate::characteristics::Procedure &proc) {
FakeEntities enities(proc.dummyArguments.size());
return enities;
}
static const FakeEntity &getDataObjectEntity(const FakeEntity &e) { return e; }
static FakeEntity
getResultEntity(const Fortran::evaluate::characteristics::Procedure &proc) {
return false;
}
/// This is the actual part that defines the FIR interface based on the
/// characteristic. It directly mutates the CallInterface members.
template <typename T>
class Fortran::lower::CallInterfaceImpl {
using CallInterface = Fortran::lower::CallInterface<T>;
using PassEntityBy = typename CallInterface::PassEntityBy;
using PassedEntity = typename CallInterface::PassedEntity;
using FirValue = typename CallInterface::FirValue;
using FortranEntity = typename CallInterface::FortranEntity;
using FirPlaceHolder = typename CallInterface::FirPlaceHolder;
using Property = typename CallInterface::Property;
using TypeAndShape = Fortran::evaluate::characteristics::TypeAndShape;
using DummyCharacteristics =
Fortran::evaluate::characteristics::DummyArgument;
public:
CallInterfaceImpl(CallInterface &i)
: interface(i), mlirContext{i.converter.getMLIRContext()} {}
void buildImplicitInterface(
const Fortran::evaluate::characteristics::Procedure &procedure) {
// Handle result
if (const std::optional<Fortran::evaluate::characteristics::FunctionResult>
&result = procedure.functionResult)
handleImplicitResult(*result);
else if (interface.side().hasAlternateReturns())
addFirResult(mlir::IndexType::get(&mlirContext),
FirPlaceHolder::resultEntityPosition, Property::Value);
// Handle arguments
const auto &argumentEntities =
getEntityContainer(interface.side().getCallDescription());
for (auto pair : llvm::zip(procedure.dummyArguments, argumentEntities)) {
const Fortran::evaluate::characteristics::DummyArgument
&argCharacteristics = std::get<0>(pair);
std::visit(
Fortran::common::visitors{
[&](const auto &dummy) {
const auto &entity = getDataObjectEntity(std::get<1>(pair));
handleImplicitDummy(&argCharacteristics, dummy, entity);
},
[&](const Fortran::evaluate::characteristics::AlternateReturn &) {
// nothing to do
},
},
argCharacteristics.u);
}
}
void buildExplicitInterface(
const Fortran::evaluate::characteristics::Procedure &procedure) {
// Handle result
if (const std::optional<Fortran::evaluate::characteristics::FunctionResult>
&result = procedure.functionResult) {
if (result->CanBeReturnedViaImplicitInterface())
handleImplicitResult(*result);
else
handleExplicitResult(*result);
} else if (interface.side().hasAlternateReturns()) {
addFirResult(mlir::IndexType::get(&mlirContext),
FirPlaceHolder::resultEntityPosition, Property::Value);
}
bool isBindC = procedure.IsBindC();
// Handle arguments
const auto &argumentEntities =
getEntityContainer(interface.side().getCallDescription());
for (auto pair : llvm::zip(procedure.dummyArguments, argumentEntities)) {
const Fortran::evaluate::characteristics::DummyArgument
&argCharacteristics = std::get<0>(pair);
std::visit(
Fortran::common::visitors{
[&](const Fortran::evaluate::characteristics::DummyDataObject
&dummy) {
const auto &entity = getDataObjectEntity(std::get<1>(pair));
if (dummy.CanBePassedViaImplicitInterface())
handleImplicitDummy(&argCharacteristics, dummy, entity);
else
handleExplicitDummy(&argCharacteristics, dummy, entity,
isBindC);
},
[&](const Fortran::evaluate::characteristics::DummyProcedure
&dummy) {
const auto &entity = getDataObjectEntity(std::get<1>(pair));
handleImplicitDummy(&argCharacteristics, dummy, entity);
},
[&](const Fortran::evaluate::characteristics::AlternateReturn &) {
// nothing to do
},
},
argCharacteristics.u);
}
}
void appendHostAssocTupleArg(mlir::Type tupTy) {
mlir::MLIRContext *ctxt = tupTy.getContext();
addFirOperand(tupTy, nextPassedArgPosition(), Property::BaseAddress,
{mlir::NamedAttribute{
mlir::StringAttr::get(ctxt, fir::getHostAssocAttrName()),
mlir::UnitAttr::get(ctxt)}});
interface.passedArguments.emplace_back(
PassedEntity{PassEntityBy::BaseAddress, std::nullopt,
interface.side().getHostAssociatedTuple(), emptyValue()});
}
static llvm::Optional<Fortran::evaluate::DynamicType> getResultDynamicType(
const Fortran::evaluate::characteristics::Procedure &procedure) {
if (const std::optional<Fortran::evaluate::characteristics::FunctionResult>
&result = procedure.functionResult)
if (const auto *resultTypeAndShape = result->GetTypeAndShape())
return resultTypeAndShape->type();
return llvm::None;
}
static bool mustPassLengthWithDummyProcedure(
const Fortran::evaluate::characteristics::Procedure &procedure) {
// When passing a character function designator `bar` as dummy procedure to
// `foo` (e.g. `foo(bar)`), pass the result length of `bar` to `foo` so that
// `bar` can be called inside `foo` even if its length is assumed there.
// From an ABI perspective, the extra length argument must be handled
// exactly as if passing a character object. Using an argument of
// fir.boxchar type gives the expected behavior: after codegen, the
// fir.boxchar lengths are added after all the arguments as extra value
// arguments (the extra arguments order is the order of the fir.boxchar).
// This ABI is compatible with ifort, nag, nvfortran, and xlf, but not
// gfortran. Gfortran does not pass the length and is therefore unable to
// handle later call to `bar` in `foo` where the length would be assumed. If
// the result is an array, nag and ifort and xlf still pass the length, but
// not nvfortran (and gfortran). It is not clear it is possible to call an
// array function with assumed length (f18 forbides defining such
// interfaces). Hence, passing the length is most likely useless, but stick
// with ifort/nag/xlf interface here.
if (llvm::Optional<Fortran::evaluate::DynamicType> type =
getResultDynamicType(procedure))
return type->category() == Fortran::common::TypeCategory::Character;
return false;
}
private:
void handleImplicitResult(
const Fortran::evaluate::characteristics::FunctionResult &result) {
if (result.IsProcedurePointer())
TODO(interface.converter.getCurrentLocation(),
"procedure pointer result not yet handled");
const Fortran::evaluate::characteristics::TypeAndShape *typeAndShape =
result.GetTypeAndShape();
assert(typeAndShape && "expect type for non proc pointer result");
Fortran::evaluate::DynamicType dynamicType = typeAndShape->type();
// Character result allocated by caller and passed as hidden arguments
if (dynamicType.category() == Fortran::common::TypeCategory::Character) {
handleImplicitCharacterResult(dynamicType);
} else if (dynamicType.category() ==
Fortran::common::TypeCategory::Derived) {
// Derived result need to be allocated by the caller and the result value
// must be saved. Derived type in implicit interface cannot have length
// parameters.
setSaveResult();
mlir::Type mlirType = translateDynamicType(dynamicType);
addFirResult(mlirType, FirPlaceHolder::resultEntityPosition,
Property::Value);
} else {
// All result other than characters/derived are simply returned by value
// in implicit interfaces
mlir::Type mlirType =
getConverter().genType(dynamicType.category(), dynamicType.kind());
addFirResult(mlirType, FirPlaceHolder::resultEntityPosition,
Property::Value);
}
}
void
handleImplicitCharacterResult(const Fortran::evaluate::DynamicType &type) {
int resultPosition = FirPlaceHolder::resultEntityPosition;
setPassedResult(PassEntityBy::AddressAndLength,
getResultEntity(interface.side().getCallDescription()));
mlir::Type lenTy = mlir::IndexType::get(&mlirContext);
std::optional<std::int64_t> constantLen = type.knownLength();
fir::CharacterType::LenType len =
constantLen ? *constantLen : fir::CharacterType::unknownLen();
mlir::Type charRefTy = fir::ReferenceType::get(
fir::CharacterType::get(&mlirContext, type.kind(), len));
mlir::Type boxCharTy = fir::BoxCharType::get(&mlirContext, type.kind());
addFirOperand(charRefTy, resultPosition, Property::CharAddress);
addFirOperand(lenTy, resultPosition, Property::CharLength);
/// For now, also return it by boxchar
addFirResult(boxCharTy, resultPosition, Property::BoxChar);
}
/// Return a vector with an attribute with the name of the argument if this
/// is a callee interface and the name is available. Otherwise, just return
/// an empty vector.
llvm::SmallVector<mlir::NamedAttribute>
dummyNameAttr(const FortranEntity &entity) {
if constexpr (std::is_same_v<FortranEntity,
std::optional<Fortran::common::Reference<
const Fortran::semantics::Symbol>>>) {
if (entity.has_value()) {
const Fortran::semantics::Symbol *argument = &*entity.value();
// "fir.bindc_name" is used for arguments for the sake of consistency
// with other attributes carrying surface syntax names in FIR.
return {mlir::NamedAttribute(
mlir::StringAttr::get(&mlirContext, "fir.bindc_name"),
mlir::StringAttr::get(&mlirContext,
toStringRef(argument->name())))};
}
}
return {};
}
void handleImplicitDummy(
const DummyCharacteristics *characteristics,
const Fortran::evaluate::characteristics::DummyDataObject &obj,
const FortranEntity &entity) {
Fortran::evaluate::DynamicType dynamicType = obj.type.type();
if (dynamicType.category() == Fortran::common::TypeCategory::Character) {
mlir::Type boxCharTy =
fir::BoxCharType::get(&mlirContext, dynamicType.kind());
addFirOperand(boxCharTy, nextPassedArgPosition(), Property::BoxChar,
dummyNameAttr(entity));
addPassedArg(PassEntityBy::BoxChar, entity, characteristics);
} else {
// non-PDT derived type allowed in implicit interface.
mlir::Type type = translateDynamicType(dynamicType);
fir::SequenceType::Shape bounds = getBounds(obj.type.shape());
if (!bounds.empty())
type = fir::SequenceType::get(bounds, type);
mlir::Type refType = fir::ReferenceType::get(type);
addFirOperand(refType, nextPassedArgPosition(), Property::BaseAddress,
dummyNameAttr(entity));
addPassedArg(PassEntityBy::BaseAddress, entity, characteristics);
}
}
// Define when an explicit argument must be passed in a fir.box.
bool dummyRequiresBox(
const Fortran::evaluate::characteristics::DummyDataObject &obj) {
using ShapeAttr = Fortran::evaluate::characteristics::TypeAndShape::Attr;
using ShapeAttrs = Fortran::evaluate::characteristics::TypeAndShape::Attrs;
constexpr ShapeAttrs shapeRequiringBox = {
ShapeAttr::AssumedShape, ShapeAttr::DeferredShape,
ShapeAttr::AssumedRank, ShapeAttr::Coarray};
if ((obj.type.attrs() & shapeRequiringBox).any())
// Need to pass shape/coshape info in fir.box.
return true;
if (obj.type.type().IsPolymorphic())
// Need to pass dynamic type info in fir.box.
return true;
if (const Fortran::semantics::DerivedTypeSpec *derived =
Fortran::evaluate::GetDerivedTypeSpec(obj.type.type()))
// Need to pass type parameters in fir.box if any.
return derived->parameters().empty();
return false;
}
mlir::Type
translateDynamicType(const Fortran::evaluate::DynamicType &dynamicType) {
Fortran::common::TypeCategory cat = dynamicType.category();
// DERIVED
if (cat == Fortran::common::TypeCategory::Derived) {
if (dynamicType.IsPolymorphic())
TODO(interface.converter.getCurrentLocation(),
"[translateDynamicType] polymorphic types");
return getConverter().genType(dynamicType.GetDerivedTypeSpec());
}
// CHARACTER with compile time constant length.
if (cat == Fortran::common::TypeCategory::Character)
if (std::optional<std::int64_t> constantLen =
toInt64(dynamicType.GetCharLength()))
return getConverter().genType(cat, dynamicType.kind(), {*constantLen});
// INTEGER, REAL, LOGICAL, COMPLEX, and CHARACTER with dynamic length.
return getConverter().genType(cat, dynamicType.kind());
}
void handleExplicitDummy(
const DummyCharacteristics *characteristics,
const Fortran::evaluate::characteristics::DummyDataObject &obj,
const FortranEntity &entity, bool isBindC) {
using Attrs = Fortran::evaluate::characteristics::DummyDataObject::Attr;
bool isValueAttr = false;
[[maybe_unused]] mlir::Location loc =
interface.converter.getCurrentLocation();
llvm::SmallVector<mlir::NamedAttribute> attrs = dummyNameAttr(entity);
auto addMLIRAttr = [&](llvm::StringRef attr) {
attrs.emplace_back(mlir::StringAttr::get(&mlirContext, attr),
mlir::UnitAttr::get(&mlirContext));
};
if (obj.attrs.test(Attrs::Optional))
addMLIRAttr(fir::getOptionalAttrName());
if (obj.attrs.test(Attrs::Asynchronous))
TODO(loc, "Asynchronous in procedure interface");
if (obj.attrs.test(Attrs::Contiguous))
addMLIRAttr(fir::getContiguousAttrName());
if (obj.attrs.test(Attrs::Value))
isValueAttr = true; // TODO: do we want an mlir::Attribute as well?
if (obj.attrs.test(Attrs::Volatile))
TODO(loc, "Volatile in procedure interface");
if (obj.attrs.test(Attrs::Target))
addMLIRAttr(fir::getTargetAttrName());
// TODO: intents that require special care (e.g finalization)
using ShapeAttr = Fortran::evaluate::characteristics::TypeAndShape::Attr;
const Fortran::evaluate::characteristics::TypeAndShape::Attrs &shapeAttrs =
obj.type.attrs();
if (shapeAttrs.test(ShapeAttr::AssumedRank))
TODO(loc, "Assumed Rank in procedure interface");
if (shapeAttrs.test(ShapeAttr::Coarray))
TODO(loc, "Coarray in procedure interface");
// So far assume that if the argument cannot be passed by implicit interface
// it must be by box. That may no be always true (e.g for simple optionals)
Fortran::evaluate::DynamicType dynamicType = obj.type.type();
mlir::Type type = translateDynamicType(dynamicType);
fir::SequenceType::Shape bounds = getBounds(obj.type.shape());
if (!bounds.empty())
type = fir::SequenceType::get(bounds, type);
if (obj.attrs.test(Attrs::Allocatable))
type = fir::HeapType::get(type);
if (obj.attrs.test(Attrs::Pointer))
type = fir::PointerType::get(type);
mlir::Type boxType = fir::BoxType::get(type);
if (obj.attrs.test(Attrs::Allocatable) || obj.attrs.test(Attrs::Pointer)) {
// Pass as fir.ref<fir.box>
mlir::Type boxRefType = fir::ReferenceType::get(boxType);
addFirOperand(boxRefType, nextPassedArgPosition(), Property::MutableBox,
attrs);
addPassedArg(PassEntityBy::MutableBox, entity, characteristics);
} else if (dummyRequiresBox(obj)) {
// Pass as fir.box
if (isValueAttr)
TODO(loc, "assumed shape dummy argument with VALUE attribute");
addFirOperand(boxType, nextPassedArgPosition(), Property::Box, attrs);
addPassedArg(PassEntityBy::Box, entity, characteristics);
} else if (dynamicType.category() ==
Fortran::common::TypeCategory::Character) {
// Pass as fir.box_char
mlir::Type boxCharTy =
fir::BoxCharType::get(&mlirContext, dynamicType.kind());
addFirOperand(boxCharTy, nextPassedArgPosition(), Property::BoxChar,
attrs);
addPassedArg(isValueAttr ? PassEntityBy::CharBoxValueAttribute
: PassEntityBy::BoxChar,
entity, characteristics);
} else {
// Pass as fir.ref unless it's by VALUE and BIND(C)
mlir::Type passType = fir::ReferenceType::get(type);
PassEntityBy passBy = PassEntityBy::BaseAddress;
Property prop = Property::BaseAddress;
if (isValueAttr) {
if (isBindC) {
passBy = PassEntityBy::Value;
prop = Property::Value;
passType = type;
} else {
passBy = PassEntityBy::BaseAddressValueAttribute;
}
}
addFirOperand(passType, nextPassedArgPosition(), prop, attrs);
addPassedArg(passBy, entity, characteristics);
}
}
void handleImplicitDummy(
const DummyCharacteristics *characteristics,
const Fortran::evaluate::characteristics::DummyProcedure &proc,
const FortranEntity &entity) {
if (proc.attrs.test(
Fortran::evaluate::characteristics::DummyProcedure::Attr::Pointer))
TODO(interface.converter.getCurrentLocation(),
"procedure pointer arguments");
// Otherwise, it is a dummy procedure.
const Fortran::evaluate::characteristics::Procedure &procedure =
proc.procedure.value();
mlir::Type funcType =
getProcedureDesignatorType(&procedure, interface.converter);
llvm::Optional<Fortran::evaluate::DynamicType> resultTy =
getResultDynamicType(procedure);
if (resultTy && mustPassLengthWithDummyProcedure(procedure)) {
// The result length of dummy procedures that are character functions must
// be passed so that the dummy procedure can be called if it has assumed
// length on the callee side.
mlir::Type tupleType =
fir::factory::getCharacterProcedureTupleType(funcType);
llvm::StringRef charProcAttr = fir::getCharacterProcedureDummyAttrName();
addFirOperand(tupleType, nextPassedArgPosition(), Property::CharProcTuple,
{mlir::NamedAttribute{
mlir::StringAttr::get(&mlirContext, charProcAttr),
mlir::UnitAttr::get(&mlirContext)}});
addPassedArg(PassEntityBy::CharProcTuple, entity, characteristics);
return;
}
addFirOperand(funcType, nextPassedArgPosition(), Property::BaseAddress);
addPassedArg(PassEntityBy::BaseAddress, entity, characteristics);
}
void handleExplicitResult(
const Fortran::evaluate::characteristics::FunctionResult &result) {
using Attr = Fortran::evaluate::characteristics::FunctionResult::Attr;
if (result.IsProcedurePointer())
TODO(interface.converter.getCurrentLocation(),
"procedure pointer results");
const Fortran::evaluate::characteristics::TypeAndShape *typeAndShape =
result.GetTypeAndShape();
assert(typeAndShape && "expect type for non proc pointer result");
mlir::Type mlirType = translateDynamicType(typeAndShape->type());
fir::SequenceType::Shape bounds = getBounds(typeAndShape->shape());
if (!bounds.empty())
mlirType = fir::SequenceType::get(bounds, mlirType);
if (result.attrs.test(Attr::Allocatable))
mlirType = fir::BoxType::get(fir::HeapType::get(mlirType));
if (result.attrs.test(Attr::Pointer))
mlirType = fir::BoxType::get(fir::PointerType::get(mlirType));
if (fir::isa_char(mlirType)) {
// Character scalar results must be passed as arguments in lowering so
// that an assumed length character function callee can access the result
// length. A function with a result requiring an explicit interface does
// not have to be compatible with assumed length function, but most
// compilers supports it.
handleImplicitCharacterResult(typeAndShape->type());
return;
}
addFirResult(mlirType, FirPlaceHolder::resultEntityPosition,
Property::Value);
// Explicit results require the caller to allocate the storage and save the
// function result in the storage with a fir.save_result.
setSaveResult();
}
fir::SequenceType::Shape getBounds(const Fortran::evaluate::Shape &shape) {
fir::SequenceType::Shape bounds;
for (const std::optional<Fortran::evaluate::ExtentExpr> &extent : shape) {
fir::SequenceType::Extent bound = fir::SequenceType::getUnknownExtent();
if (std::optional<std::int64_t> i = toInt64(extent))
bound = *i;
bounds.emplace_back(bound);
}
return bounds;
}
std::optional<std::int64_t>
toInt64(std::optional<
Fortran::evaluate::Expr<Fortran::evaluate::SubscriptInteger>>
expr) {
if (expr)
return Fortran::evaluate::ToInt64(Fortran::evaluate::Fold(
getConverter().getFoldingContext(), toEvExpr(*expr)));
return std::nullopt;
}
void
addFirOperand(mlir::Type type, int entityPosition, Property p,
llvm::ArrayRef<mlir::NamedAttribute> attributes = llvm::None) {
interface.inputs.emplace_back(
FirPlaceHolder{type, entityPosition, p, attributes});
}
void
addFirResult(mlir::Type type, int entityPosition, Property p,
llvm::ArrayRef<mlir::NamedAttribute> attributes = llvm::None) {
interface.outputs.emplace_back(
FirPlaceHolder{type, entityPosition, p, attributes});
}
void addPassedArg(PassEntityBy p, FortranEntity entity,
const DummyCharacteristics *characteristics) {
interface.passedArguments.emplace_back(
PassedEntity{p, entity, emptyValue(), emptyValue(), characteristics});
}
void setPassedResult(PassEntityBy p, FortranEntity entity) {
interface.passedResult =
PassedEntity{p, entity, emptyValue(), emptyValue()};
}
void setSaveResult() { interface.saveResult = true; }
int nextPassedArgPosition() { return interface.passedArguments.size(); }
static FirValue emptyValue() {
if constexpr (std::is_same_v<Fortran::lower::CalleeInterface, T>) {
return {};
} else {
return -1;
}
}
Fortran::lower::AbstractConverter &getConverter() {
return interface.converter;
}
CallInterface &interface;
mlir::MLIRContext &mlirContext;
};
template <typename T>
bool Fortran::lower::CallInterface<T>::PassedEntity::isOptional() const {
if (!characteristics)
return false;
return characteristics->IsOptional();
}
template <typename T>
bool Fortran::lower::CallInterface<T>::PassedEntity::mayBeModifiedByCall()
const {
if (!characteristics)
return true;
return characteristics->GetIntent() != Fortran::common::Intent::In;
}
template <typename T>
bool Fortran::lower::CallInterface<T>::PassedEntity::mayBeReadByCall() const {
if (!characteristics)
return true;
return characteristics->GetIntent() != Fortran::common::Intent::Out;
}
template <typename T>
void Fortran::lower::CallInterface<T>::determineInterface(
bool isImplicit,
const Fortran::evaluate::characteristics::Procedure &procedure) {
CallInterfaceImpl<T> impl(*this);
if (isImplicit)
impl.buildImplicitInterface(procedure);
else
impl.buildExplicitInterface(procedure);
// We only expect the extra host asspciations argument from the callee side as
// the definition of internal procedures will be present, and we'll always
// have a FuncOp definition in the ModuleOp, when lowering.
if constexpr (std::is_same_v<T, Fortran::lower::CalleeInterface>) {
if (side().hasHostAssociated())
impl.appendHostAssocTupleArg(side().getHostAssociatedTy());
}
}
template <typename T>
mlir::FunctionType Fortran::lower::CallInterface<T>::genFunctionType() {
llvm::SmallVector<mlir::Type> returnTys;
llvm::SmallVector<mlir::Type> inputTys;
for (const FirPlaceHolder &placeHolder : outputs)
returnTys.emplace_back(placeHolder.type);
for (const FirPlaceHolder &placeHolder : inputs)
inputTys.emplace_back(placeHolder.type);
return mlir::FunctionType::get(&converter.getMLIRContext(), inputTys,
returnTys);
}
template <typename T>
llvm::SmallVector<mlir::Type>
Fortran::lower::CallInterface<T>::getResultType() const {
llvm::SmallVector<mlir::Type> types;
for (const FirPlaceHolder &out : outputs)
types.emplace_back(out.type);
return types;
}
template class Fortran::lower::CallInterface<Fortran::lower::CalleeInterface>;
template class Fortran::lower::CallInterface<Fortran::lower::CallerInterface>;
//===----------------------------------------------------------------------===//
// Function Type Translation
//===----------------------------------------------------------------------===//
/// Build signature from characteristics when there is no Fortran entity to
/// associate with the arguments (i.e, this is not a call site or a procedure
/// declaration. This is needed when dealing with function pointers/dummy
/// arguments.
class SignatureBuilder;
template <>
struct Fortran::lower::PassedEntityTypes<SignatureBuilder> {
using FortranEntity = FakeEntity;
using FirValue = int;
};
/// SignatureBuilder is a CRTP implementation of CallInterface intended to
/// help translating characteristics::Procedure to mlir::FunctionType using
/// the CallInterface translation.
class SignatureBuilder
: public Fortran::lower::CallInterface<SignatureBuilder> {
public:
SignatureBuilder(const Fortran::evaluate::characteristics::Procedure &p,
Fortran::lower::AbstractConverter &c, bool forceImplicit)
: CallInterface{c}, proc{p} {
bool isImplicit = forceImplicit || proc.CanBeCalledViaImplicitInterface();
determineInterface(isImplicit, proc);
}
/// Does the procedure characteristics being translated have alternate
/// returns ?
bool hasAlternateReturns() const {
for (const Fortran::evaluate::characteristics::DummyArgument &dummy :
proc.dummyArguments)
if (std::holds_alternative<
Fortran::evaluate::characteristics::AlternateReturn>(dummy.u))
return true;
return false;
};
/// This is only here to fulfill CRTP dependencies and should not be called.
std::string getMangledName() const {
llvm_unreachable("trying to get name from SignatureBuilder");
}
/// This is only here to fulfill CRTP dependencies and should not be called.
mlir::Location getCalleeLocation() const {
llvm_unreachable("trying to get callee location from SignatureBuilder");
}
/// This is only here to fulfill CRTP dependencies and should not be called.
const Fortran::semantics::Symbol *getProcedureSymbol() const {
llvm_unreachable("trying to get callee symbol from SignatureBuilder");
};
Fortran::evaluate::characteristics::Procedure characterize() const {
return proc;
}
/// SignatureBuilder cannot be used on main program.
static constexpr bool isMainProgram() { return false; }
/// Return the characteristics::Procedure that is being translated to
/// mlir::FunctionType.
const Fortran::evaluate::characteristics::Procedure &
getCallDescription() const {
return proc;
}
/// This is not the description of an indirect call.
static constexpr bool isIndirectCall() { return false; }
/// Return the translated signature.
mlir::FunctionType getFunctionType() { return genFunctionType(); }
// Copy of base implementation.
static constexpr bool hasHostAssociated() { return false; }
mlir::Type getHostAssociatedTy() const {
llvm_unreachable("getting host associated type in SignatureBuilder");
}
private:
const Fortran::evaluate::characteristics::Procedure &proc;
};
mlir::FunctionType Fortran::lower::translateSignature(
const Fortran::evaluate::ProcedureDesignator &proc,
Fortran::lower::AbstractConverter &converter) {
std::optional<Fortran::evaluate::characteristics::Procedure> characteristics =
Fortran::evaluate::characteristics::Procedure::Characterize(
proc, converter.getFoldingContext());
// Most unrestricted intrinsic characteristic has the Elemental attribute
// which triggers CanBeCalledViaImplicitInterface to return false. However,
// using implicit interface rules is just fine here.
bool forceImplicit = proc.GetSpecificIntrinsic();
return SignatureBuilder{characteristics.value(), converter, forceImplicit}
.getFunctionType();
}
mlir::FuncOp Fortran::lower::getOrDeclareFunction(
llvm::StringRef name, const Fortran::evaluate::ProcedureDesignator &proc,
Fortran::lower::AbstractConverter &converter) {
mlir::ModuleOp module = converter.getModuleOp();
mlir::FuncOp func = fir::FirOpBuilder::getNamedFunction(module, name);
if (func)
return func;
const Fortran::semantics::Symbol *symbol = proc.GetSymbol();
assert(symbol && "non user function in getOrDeclareFunction");
// getOrDeclareFunction is only used for functions not defined in the current
// program unit, so use the location of the procedure designator symbol, which
// is the first occurrence of the procedure in the program unit.
mlir::Location loc = converter.genLocation(symbol->name());
std::optional<Fortran::evaluate::characteristics::Procedure> characteristics =
Fortran::evaluate::characteristics::Procedure::Characterize(
proc, converter.getFoldingContext());
mlir::FunctionType ty = SignatureBuilder{characteristics.value(), converter,
/*forceImplicit=*/false}
.getFunctionType();
mlir::FuncOp newFunc =
fir::FirOpBuilder::createFunction(loc, module, name, ty);
addSymbolAttribute(newFunc, *symbol, converter.getMLIRContext());
return newFunc;
}
// Is it required to pass a dummy procedure with \p characteristics as a tuple
// containing the function address and the result length ?
static bool mustPassLengthWithDummyProcedure(
const std::optional<Fortran::evaluate::characteristics::Procedure>
&characteristics) {
return characteristics &&
Fortran::lower::CallInterfaceImpl<SignatureBuilder>::
mustPassLengthWithDummyProcedure(*characteristics);
}
bool Fortran::lower::mustPassLengthWithDummyProcedure(
const Fortran::evaluate::ProcedureDesignator &procedure,
Fortran::lower::AbstractConverter &converter) {
std::optional<Fortran::evaluate::characteristics::Procedure> characteristics =
Fortran::evaluate::characteristics::Procedure::Characterize(
procedure, converter.getFoldingContext());
return ::mustPassLengthWithDummyProcedure(characteristics);
}
mlir::Type Fortran::lower::getDummyProcedureType(
const Fortran::semantics::Symbol &dummyProc,
Fortran::lower::AbstractConverter &converter) {
std::optional<Fortran::evaluate::characteristics::Procedure> iface =
Fortran::evaluate::characteristics::Procedure::Characterize(
dummyProc, converter.getFoldingContext());
mlir::Type procType = getProcedureDesignatorType(
iface.has_value() ? &*iface : nullptr, converter);
if (::mustPassLengthWithDummyProcedure(iface))
return fir::factory::getCharacterProcedureTupleType(procType);
return procType;
}