Files
clang-p2996/flang/lib/Lower/ConvertCall.cpp
Jean Perier 3909b60a3c [flang][NFC] Remove CallBuilder class
The methods of CallBuilder do need to belong to a class.
This was made to avoid having to propagate generic lowering context
(converter, symbol mappings, location and StatementContext).

Packaging them together will actually make it harder to share the code
for user and intrinsic elemental lowering (I plan to use C++ CRTP),
and it is also misleading: one could think there is something going
with the class state while lowering the function while there is not
(and there should not be).

Removes the class and turns the methods into static functions.
Add a new CallContext class to solve the argument threading
inconvenience.

This contains no functional changes at all.

Differential Revision: https://reviews.llvm.org/D141510
2023-01-12 10:16:09 +01:00

859 lines
38 KiB
C++

//===-- ConvertCall.cpp ---------------------------------------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
//
// Coding style: https://mlir.llvm.org/getting_started/DeveloperGuide/
//
//===----------------------------------------------------------------------===//
#include "flang/Lower/ConvertCall.h"
#include "flang/Lower/ConvertExprToHLFIR.h"
#include "flang/Lower/ConvertVariable.h"
#include "flang/Lower/CustomIntrinsicCall.h"
#include "flang/Lower/IntrinsicCall.h"
#include "flang/Lower/StatementContext.h"
#include "flang/Lower/SymbolMap.h"
#include "flang/Optimizer/Builder/BoxValue.h"
#include "flang/Optimizer/Builder/Character.h"
#include "flang/Optimizer/Builder/FIRBuilder.h"
#include "flang/Optimizer/Builder/LowLevelIntrinsics.h"
#include "flang/Optimizer/Builder/MutableBox.h"
#include "flang/Optimizer/Builder/Todo.h"
#include "flang/Optimizer/Dialect/FIROpsSupport.h"
#include "flang/Optimizer/HLFIR/HLFIROps.h"
#include "llvm/Support/Debug.h"
#include <optional>
#define DEBUG_TYPE "flang-lower-expr"
/// Helper to package a Value and its properties into an ExtendedValue.
static fir::ExtendedValue toExtendedValue(mlir::Location loc, mlir::Value base,
llvm::ArrayRef<mlir::Value> extents,
llvm::ArrayRef<mlir::Value> lengths) {
mlir::Type type = base.getType();
if (type.isa<fir::BaseBoxType>())
return fir::BoxValue(base, /*lbounds=*/{}, lengths, extents);
type = fir::unwrapRefType(type);
if (type.isa<fir::BaseBoxType>())
return fir::MutableBoxValue(base, lengths, /*mutableProperties*/ {});
if (auto seqTy = type.dyn_cast<fir::SequenceType>()) {
if (seqTy.getDimension() != extents.size())
fir::emitFatalError(loc, "incorrect number of extents for array");
if (seqTy.getEleTy().isa<fir::CharacterType>()) {
if (lengths.empty())
fir::emitFatalError(loc, "missing length for character");
assert(lengths.size() == 1);
return fir::CharArrayBoxValue(base, lengths[0], extents);
}
return fir::ArrayBoxValue(base, extents);
}
if (type.isa<fir::CharacterType>()) {
if (lengths.empty())
fir::emitFatalError(loc, "missing length for character");
assert(lengths.size() == 1);
return fir::CharBoxValue(base, lengths[0]);
}
return base;
}
/// Lower a type(C_PTR/C_FUNPTR) argument with VALUE attribute into a
/// reference. A C pointer can correspond to a Fortran dummy argument of type
/// C_PTR with the VALUE attribute. (see 18.3.6 note 3).
static mlir::Value
genRecordCPtrValueArg(Fortran::lower::AbstractConverter &converter,
mlir::Value rec, mlir::Type ty) {
fir::FirOpBuilder &builder = converter.getFirOpBuilder();
mlir::Location loc = converter.getCurrentLocation();
mlir::Value cAddr = fir::factory::genCPtrOrCFunptrAddr(builder, loc, rec, ty);
mlir::Value cVal = builder.create<fir::LoadOp>(loc, cAddr);
return builder.createConvert(loc, cAddr.getType(), cVal);
}
// Find the argument that corresponds to the host associations.
// Verify some assumptions about how the signature was built here.
[[maybe_unused]] static unsigned findHostAssocTuplePos(mlir::func::FuncOp fn) {
// Scan the argument list from last to first as the host associations are
// appended for now.
for (unsigned i = fn.getNumArguments(); i > 0; --i)
if (fn.getArgAttr(i - 1, fir::getHostAssocAttrName())) {
// Host assoc tuple must be last argument (for now).
assert(i == fn.getNumArguments() && "tuple must be last");
return i - 1;
}
llvm_unreachable("anyFuncArgsHaveAttr failed");
}
mlir::Value
Fortran::lower::argumentHostAssocs(Fortran::lower::AbstractConverter &converter,
mlir::Value arg) {
if (auto addr = mlir::dyn_cast_or_null<fir::AddrOfOp>(arg.getDefiningOp())) {
auto &builder = converter.getFirOpBuilder();
if (auto funcOp = builder.getNamedFunction(addr.getSymbol()))
if (fir::anyFuncArgsHaveAttr(funcOp, fir::getHostAssocAttrName()))
return converter.hostAssocTupleValue();
}
return {};
}
fir::ExtendedValue Fortran::lower::genCallOpAndResult(
mlir::Location loc, Fortran::lower::AbstractConverter &converter,
Fortran::lower::SymMap &symMap, Fortran::lower::StatementContext &stmtCtx,
Fortran::lower::CallerInterface &caller, mlir::FunctionType callSiteType,
std::optional<mlir::Type> resultType) {
fir::FirOpBuilder &builder = converter.getFirOpBuilder();
using PassBy = Fortran::lower::CallerInterface::PassEntityBy;
// Handle cases where caller must allocate the result or a fir.box for it.
bool mustPopSymMap = false;
if (caller.mustMapInterfaceSymbols()) {
symMap.pushScope();
mustPopSymMap = true;
Fortran::lower::mapCallInterfaceSymbols(converter, caller, symMap);
}
// If this is an indirect call, retrieve the function address. Also retrieve
// the result length if this is a character function (note that this length
// will be used only if there is no explicit length in the local interface).
mlir::Value funcPointer;
mlir::Value charFuncPointerLength;
if (const Fortran::semantics::Symbol *sym =
caller.getIfIndirectCallSymbol()) {
funcPointer = symMap.lookupSymbol(*sym).getAddr();
if (!funcPointer)
fir::emitFatalError(loc, "failed to find indirect call symbol address");
if (fir::isCharacterProcedureTuple(funcPointer.getType(),
/*acceptRawFunc=*/false))
std::tie(funcPointer, charFuncPointerLength) =
fir::factory::extractCharacterProcedureTuple(builder, loc,
funcPointer);
}
mlir::IndexType idxTy = builder.getIndexType();
auto lowerSpecExpr = [&](const auto &expr) -> mlir::Value {
mlir::Value convertExpr = builder.createConvert(
loc, idxTy, fir::getBase(converter.genExprValue(expr, stmtCtx)));
return fir::factory::genMaxWithZero(builder, loc, convertExpr);
};
llvm::SmallVector<mlir::Value> resultLengths;
auto allocatedResult = [&]() -> std::optional<fir::ExtendedValue> {
llvm::SmallVector<mlir::Value> extents;
llvm::SmallVector<mlir::Value> lengths;
if (!caller.callerAllocateResult())
return {};
mlir::Type type = caller.getResultStorageType();
if (type.isa<fir::SequenceType>())
caller.walkResultExtents([&](const Fortran::lower::SomeExpr &e) {
extents.emplace_back(lowerSpecExpr(e));
});
caller.walkResultLengths([&](const Fortran::lower::SomeExpr &e) {
lengths.emplace_back(lowerSpecExpr(e));
});
// Result length parameters should not be provided to box storage
// allocation and save_results, but they are still useful information to
// keep in the ExtendedValue if non-deferred.
if (!type.isa<fir::BoxType>()) {
if (fir::isa_char(fir::unwrapSequenceType(type)) && lengths.empty()) {
// Calling an assumed length function. This is only possible if this
// is a call to a character dummy procedure.
if (!charFuncPointerLength)
fir::emitFatalError(loc, "failed to retrieve character function "
"length while calling it");
lengths.push_back(charFuncPointerLength);
}
resultLengths = lengths;
}
if (!extents.empty() || !lengths.empty()) {
auto *bldr = &converter.getFirOpBuilder();
auto stackSaveFn = fir::factory::getLlvmStackSave(builder);
auto stackSaveSymbol = bldr->getSymbolRefAttr(stackSaveFn.getName());
mlir::Value sp = bldr->create<fir::CallOp>(
loc, stackSaveFn.getFunctionType().getResults(),
stackSaveSymbol, mlir::ValueRange{})
.getResult(0);
stmtCtx.attachCleanup([bldr, loc, sp]() {
auto stackRestoreFn = fir::factory::getLlvmStackRestore(*bldr);
auto stackRestoreSymbol =
bldr->getSymbolRefAttr(stackRestoreFn.getName());
bldr->create<fir::CallOp>(loc,
stackRestoreFn.getFunctionType().getResults(),
stackRestoreSymbol, mlir::ValueRange{sp});
});
}
mlir::Value temp =
builder.createTemporary(loc, type, ".result", extents, resultLengths);
return toExtendedValue(loc, temp, extents, lengths);
}();
if (mustPopSymMap)
symMap.popScope();
// Place allocated result or prepare the fir.save_result arguments.
mlir::Value arrayResultShape;
if (allocatedResult) {
if (std::optional<Fortran::lower::CallInterface<
Fortran::lower::CallerInterface>::PassedEntity>
resultArg = caller.getPassedResult()) {
if (resultArg->passBy == PassBy::AddressAndLength)
caller.placeAddressAndLengthInput(*resultArg,
fir::getBase(*allocatedResult),
fir::getLen(*allocatedResult));
else if (resultArg->passBy == PassBy::BaseAddress)
caller.placeInput(*resultArg, fir::getBase(*allocatedResult));
else
fir::emitFatalError(
loc, "only expect character scalar result to be passed by ref");
} else {
assert(caller.mustSaveResult());
arrayResultShape = allocatedResult->match(
[&](const fir::CharArrayBoxValue &) {
return builder.createShape(loc, *allocatedResult);
},
[&](const fir::ArrayBoxValue &) {
return builder.createShape(loc, *allocatedResult);
},
[&](const auto &) { return mlir::Value{}; });
}
}
// In older Fortran, procedure argument types are inferred. This may lead
// different view of what the function signature is in different locations.
// Casts are inserted as needed below to accommodate this.
// The mlir::func::FuncOp type prevails, unless it has a different number of
// arguments which can happen in legal program if it was passed as a dummy
// procedure argument earlier with no further type information.
mlir::SymbolRefAttr funcSymbolAttr;
bool addHostAssociations = false;
if (!funcPointer) {
mlir::FunctionType funcOpType = caller.getFuncOp().getFunctionType();
mlir::SymbolRefAttr symbolAttr =
builder.getSymbolRefAttr(caller.getMangledName());
if (callSiteType.getNumResults() == funcOpType.getNumResults() &&
callSiteType.getNumInputs() + 1 == funcOpType.getNumInputs() &&
fir::anyFuncArgsHaveAttr(caller.getFuncOp(),
fir::getHostAssocAttrName())) {
// The number of arguments is off by one, and we're lowering a function
// with host associations. Modify call to include host associations
// argument by appending the value at the end of the operands.
assert(funcOpType.getInput(findHostAssocTuplePos(caller.getFuncOp())) ==
converter.hostAssocTupleValue().getType());
addHostAssociations = true;
}
if (!addHostAssociations &&
(callSiteType.getNumResults() != funcOpType.getNumResults() ||
callSiteType.getNumInputs() != funcOpType.getNumInputs())) {
// Deal with argument number mismatch by making a function pointer so
// that function type cast can be inserted. Do not emit a warning here
// because this can happen in legal program if the function is not
// defined here and it was first passed as an argument without any more
// information.
funcPointer = builder.create<fir::AddrOfOp>(loc, funcOpType, symbolAttr);
} else if (callSiteType.getResults() != funcOpType.getResults()) {
// Implicit interface result type mismatch are not standard Fortran, but
// some compilers are not complaining about it. The front end is not
// protecting lowering from this currently. Support this with a
// discouraging warning.
LLVM_DEBUG(mlir::emitWarning(
loc, "a return type mismatch is not standard compliant and may "
"lead to undefined behavior."));
// Cast the actual function to the current caller implicit type because
// that is the behavior we would get if we could not see the definition.
funcPointer = builder.create<fir::AddrOfOp>(loc, funcOpType, symbolAttr);
} else {
funcSymbolAttr = symbolAttr;
}
}
mlir::FunctionType funcType =
funcPointer ? callSiteType : caller.getFuncOp().getFunctionType();
llvm::SmallVector<mlir::Value> operands;
// First operand of indirect call is the function pointer. Cast it to
// required function type for the call to handle procedures that have a
// compatible interface in Fortran, but that have different signatures in
// FIR.
if (funcPointer) {
operands.push_back(
funcPointer.getType().isa<fir::BoxProcType>()
? builder.create<fir::BoxAddrOp>(loc, funcType, funcPointer)
: builder.createConvert(loc, funcType, funcPointer));
}
// Deal with potential mismatches in arguments types. Passing an array to a
// scalar argument should for instance be tolerated here.
bool callingImplicitInterface = caller.canBeCalledViaImplicitInterface();
for (auto [fst, snd] : llvm::zip(caller.getInputs(), funcType.getInputs())) {
// When passing arguments to a procedure that can be called by implicit
// interface, allow any character actual arguments to be passed to dummy
// arguments of any type and vice versa.
mlir::Value cast;
auto *context = builder.getContext();
if (snd.isa<fir::BoxProcType>() &&
fst.getType().isa<mlir::FunctionType>()) {
auto funcTy =
mlir::FunctionType::get(context, std::nullopt, std::nullopt);
auto boxProcTy = builder.getBoxProcType(funcTy);
if (mlir::Value host = argumentHostAssocs(converter, fst)) {
cast = builder.create<fir::EmboxProcOp>(
loc, boxProcTy, llvm::ArrayRef<mlir::Value>{fst, host});
} else {
cast = builder.create<fir::EmboxProcOp>(loc, boxProcTy, fst);
}
} else {
mlir::Type fromTy = fir::unwrapRefType(fst.getType());
if (fir::isa_builtin_cptr_type(fromTy) &&
Fortran::lower::isCPtrArgByValueType(snd)) {
cast = genRecordCPtrValueArg(converter, fst, fromTy);
} else if (fir::isa_derived(snd)) {
// FIXME: This seems like a serious bug elsewhere in lowering. Paper
// over the problem for now.
TODO(loc, "derived type argument passed by value");
} else {
cast = builder.convertWithSemantics(loc, snd, fst,
callingImplicitInterface);
}
}
operands.push_back(cast);
}
// Add host associations as necessary.
if (addHostAssociations)
operands.push_back(converter.hostAssocTupleValue());
mlir::Value callResult;
unsigned callNumResults;
if (caller.requireDispatchCall()) {
// Procedure call requiring a dynamic dispatch. Call is created with
// fir.dispatch.
// Get the raw procedure name. The procedure name is not mangled in the
// binding table.
const auto &ultimateSymbol =
caller.getCallDescription().proc().GetSymbol()->GetUltimate();
auto procName = toStringRef(ultimateSymbol.name());
fir::DispatchOp dispatch;
if (std::optional<unsigned> passArg = caller.getPassArgIndex()) {
// PASS, PASS(arg-name)
dispatch = builder.create<fir::DispatchOp>(
loc, funcType.getResults(), builder.getStringAttr(procName),
operands[*passArg], operands, builder.getI32IntegerAttr(*passArg));
} else {
// NOPASS
const Fortran::evaluate::Component *component =
caller.getCallDescription().proc().GetComponent();
assert(component && "expect component for type-bound procedure call.");
fir::ExtendedValue pass =
symMap.lookupSymbol(component->GetFirstSymbol()).toExtendedValue();
mlir::Value passObject = fir::getBase(pass);
if (fir::isa_ref_type(passObject.getType()))
passObject = builder.create<fir::ConvertOp>(
loc, passObject.getType().dyn_cast<fir::ReferenceType>().getEleTy(),
passObject);
dispatch = builder.create<fir::DispatchOp>(
loc, funcType.getResults(), builder.getStringAttr(procName),
passObject, operands, nullptr);
}
callResult = dispatch.getResult(0);
callNumResults = dispatch.getNumResults();
} else {
// Standard procedure call with fir.call.
auto call = builder.create<fir::CallOp>(loc, funcType.getResults(),
funcSymbolAttr, operands);
callResult = call.getResult(0);
callNumResults = call.getNumResults();
}
if (caller.mustSaveResult()) {
assert(allocatedResult.has_value());
builder.create<fir::SaveResultOp>(loc, callResult,
fir::getBase(*allocatedResult),
arrayResultShape, resultLengths);
}
if (allocatedResult) {
allocatedResult->match(
[&](const fir::MutableBoxValue &box) {
if (box.isAllocatable()) {
// 9.7.3.2 point 4. Finalize allocatables.
fir::FirOpBuilder *bldr = &converter.getFirOpBuilder();
stmtCtx.attachCleanup([bldr, loc, box]() {
fir::factory::genFinalization(*bldr, loc, box);
});
}
},
[](const auto &) {});
return *allocatedResult;
}
if (!resultType)
return mlir::Value{}; // subroutine call
// For now, Fortran return values are implemented with a single MLIR
// function return value.
assert(callNumResults == 1 && "Expected exactly one result in FUNCTION call");
(void)callNumResults;
// Call a BIND(C) function that return a char.
if (caller.characterize().IsBindC() &&
funcType.getResults()[0].isa<fir::CharacterType>()) {
fir::CharacterType charTy =
funcType.getResults()[0].dyn_cast<fir::CharacterType>();
mlir::Value len = builder.createIntegerConstant(
loc, builder.getCharacterLengthType(), charTy.getLen());
return fir::CharBoxValue{callResult, len};
}
return callResult;
}
static hlfir::EntityWithAttributes genStmtFunctionRef(
mlir::Location loc, Fortran::lower::AbstractConverter &converter,
Fortran::lower::SymMap &symMap, Fortran::lower::StatementContext &stmtCtx,
const Fortran::evaluate::ProcedureRef &procRef) {
const Fortran::semantics::Symbol *symbol = procRef.proc().GetSymbol();
assert(symbol && "expected symbol in ProcedureRef of statement functions");
const auto &details = symbol->get<Fortran::semantics::SubprogramDetails>();
fir::FirOpBuilder &builder = converter.getFirOpBuilder();
// Statement functions have their own scope, we just need to associate
// the dummy symbols to argument expressions. There are no
// optional/alternate return arguments. Statement functions cannot be
// recursive (directly or indirectly) so it is safe to add dummy symbols to
// the local map here.
symMap.pushScope();
llvm::SmallVector<hlfir::AssociateOp> exprAssociations;
for (auto [arg, bind] : llvm::zip(details.dummyArgs(), procRef.arguments())) {
assert(arg && "alternate return in statement function");
assert(bind && "optional argument in statement function");
const auto *expr = bind->UnwrapExpr();
// TODO: assumed type in statement function, that surprisingly seems
// allowed, probably because nobody thought of restricting this usage.
// gfortran/ifort compiles this.
assert(expr && "assumed type used as statement function argument");
// As per Fortran 2018 C1580, statement function arguments can only be
// scalars.
// The only care is to use the dummy character explicit length if any
// instead of the actual argument length (that can be bigger).
hlfir::EntityWithAttributes loweredArg = Fortran::lower::convertExprToHLFIR(
loc, converter, *expr, symMap, stmtCtx);
fir::FortranVariableOpInterface variableIface = loweredArg.getIfVariable();
if (!variableIface) {
// So far only FortranVariableOpInterface can be mapped to symbols.
// Create an hlfir.associate to create a variable from a potential
// value argument.
mlir::Type argType = converter.genType(*arg);
auto associate = hlfir::genAssociateExpr(
loc, builder, loweredArg, argType, toStringRef(arg->name()));
exprAssociations.push_back(associate);
variableIface = associate;
}
const Fortran::semantics::DeclTypeSpec *type = arg->GetType();
if (type &&
type->category() == Fortran::semantics::DeclTypeSpec::Character) {
// Instantiate character as if it was a normal dummy argument so that the
// statement function dummy character length is applied and dealt with
// correctly.
symMap.addSymbol(*arg, variableIface.getBase());
Fortran::lower::mapSymbolAttributes(converter, *arg, symMap, stmtCtx);
} else {
// No need to create an extra hlfir.declare otherwise for
// numerical and logical scalar dummies.
symMap.addVariableDefinition(*arg, variableIface);
}
}
// Explicitly map statement function host associated symbols to their
// parent scope lowered symbol box.
for (const Fortran::semantics::SymbolRef &sym :
Fortran::evaluate::CollectSymbols(*details.stmtFunction()))
if (const auto *details =
sym->detailsIf<Fortran::semantics::HostAssocDetails>())
converter.copySymbolBinding(details->symbol(), sym);
hlfir::Entity result = Fortran::lower::convertExprToHLFIR(
loc, converter, details.stmtFunction().value(), symMap, stmtCtx);
symMap.popScope();
// The result must not be a variable.
result = hlfir::loadTrivialScalar(loc, builder, result);
if (result.isVariable())
result = hlfir::Entity{builder.create<hlfir::AsExprOp>(loc, result)};
for (auto associate : exprAssociations)
builder.create<hlfir::EndAssociateOp>(loc, associate);
return hlfir::EntityWithAttributes{result};
}
namespace {
// Structure to hold the information about the call and the lowering context.
// This structure is intended to help threading the information
// through the various lowering calls without having to pass every
// required structure one by one.
struct CallContext {
CallContext(const Fortran::evaluate::ProcedureRef &procRef,
std::optional<mlir::Type> resultType, mlir::Location loc,
Fortran::lower::AbstractConverter &converter,
Fortran::lower::SymMap &symMap,
Fortran::lower::StatementContext &stmtCtx)
: procRef{procRef}, converter{converter}, symMap{symMap},
stmtCtx{stmtCtx}, resultType{resultType}, loc{loc} {}
fir::FirOpBuilder &getBuilder() { return converter.getFirOpBuilder(); }
/// Is this a call to an elemental procedure with at least one array argument?
bool isElementalProcWithArrayArgs() const {
if (procRef.IsElemental())
for (const std::optional<Fortran::evaluate::ActualArgument> &arg :
procRef.arguments())
if (arg && arg->Rank() != 0)
return true;
return false;
}
/// Is this a statement function reference?
bool isStatementFunctionCall() const {
if (const Fortran::semantics::Symbol *symbol = procRef.proc().GetSymbol())
if (const auto *details =
symbol->detailsIf<Fortran::semantics::SubprogramDetails>())
return details->stmtFunction().has_value();
return false;
}
const Fortran::evaluate::ProcedureRef &procRef;
Fortran::lower::AbstractConverter &converter;
Fortran::lower::SymMap &symMap;
Fortran::lower::StatementContext &stmtCtx;
std::optional<mlir::Type> resultType;
mlir::Location loc;
};
/// This structure holds the initial lowered value of an actual argument that
/// was lowered regardless of the interface, and it holds whether or not it
/// may be absent at runtime and the dummy is optional.
struct PreparedActualArgument {
hlfir::Entity actual;
bool handleDynamicOptional;
};
} // namespace
/// Vector of pre-lowered actual arguments. nullopt if the actual is
/// "statically" absent (if it was not syntactically provided).
using PreparedActualArguments =
llvm::SmallVector<std::optional<PreparedActualArgument>>;
// Helper to transform a fir::ExtendedValue to an hlfir::EntityWithAttributes.
static hlfir::EntityWithAttributes
extendedValueToHlfirEntity(mlir::Location loc, fir::FirOpBuilder &builder,
const fir::ExtendedValue &exv,
llvm::StringRef name) {
mlir::Value firBase = fir::getBase(exv);
if (fir::isa_trivial(firBase.getType()))
return hlfir::EntityWithAttributes{firBase};
return hlfir::genDeclare(loc, builder, exv, name,
fir::FortranVariableFlagsAttr{});
}
/// Lower calls to user procedures with actual arguments that have been
/// pre-lowered but not yet prepared according to the interface.
/// This can be called for elemental procedures, but only with scalar
/// arguments: if there are array arguments, it must be provided with
/// the array argument elements value and will return the corresponding
/// scalar result value.
static std::optional<hlfir::EntityWithAttributes>
genUserCall(PreparedActualArguments &loweredActuals,
Fortran::lower::CallerInterface &caller,
mlir::FunctionType callSiteType, CallContext &callContext) {
using PassBy = Fortran::lower::CallerInterface::PassEntityBy;
mlir::Location loc = callContext.loc;
fir::FirOpBuilder &builder = callContext.getBuilder();
llvm::SmallVector<hlfir::AssociateOp> exprAssociations;
for (auto [preparedActual, arg] :
llvm::zip(loweredActuals, caller.getPassedArguments())) {
mlir::Type argTy = callSiteType.getInput(arg.firArgument);
if (!preparedActual) {
// Optional dummy argument for which there is no actual argument.
caller.placeInput(arg, builder.create<fir::AbsentOp>(loc, argTy));
continue;
}
hlfir::Entity actual = preparedActual->actual;
const auto *expr = arg.entity->UnwrapExpr();
if (!expr)
TODO(loc, "assumed type actual argument");
if (preparedActual->handleDynamicOptional)
TODO(loc, "passing optional arguments in HLFIR");
const bool isSimplyContiguous =
actual.isScalar() ||
Fortran::evaluate::IsSimplyContiguous(
*expr, callContext.converter.getFoldingContext());
switch (arg.passBy) {
case PassBy::Value: {
// True pass-by-value semantics.
auto value = hlfir::loadTrivialScalar(loc, builder, actual);
if (!value.isValue())
TODO(loc, "Passing CPTR an CFUNCTPTR VALUE in HLFIR");
caller.placeInput(arg, builder.createConvert(loc, argTy, value));
} break;
case PassBy::BaseAddressValueAttribute: {
// VALUE attribute or pass-by-reference to a copy semantics. (byval*)
TODO(loc, "HLFIR PassBy::BaseAddressValueAttribute");
} break;
case PassBy::BaseAddress:
case PassBy::BoxChar: {
hlfir::Entity entity = actual;
if (entity.isVariable()) {
entity = hlfir::derefPointersAndAllocatables(loc, builder, entity);
// Copy-in non contiguous variable
if (!isSimplyContiguous)
TODO(loc, "HLFIR copy-in/copy-out");
} else {
hlfir::AssociateOp associate = hlfir::genAssociateExpr(
loc, builder, entity, argTy, "adapt.valuebyref");
exprAssociations.push_back(associate);
entity = hlfir::Entity{associate.getBase()};
}
mlir::Value addr =
arg.passBy == PassBy::BaseAddress
? hlfir::genVariableRawAddress(loc, builder, entity)
: hlfir::genVariableBoxChar(loc, builder, entity);
caller.placeInput(arg, builder.createConvert(loc, argTy, addr));
} break;
case PassBy::CharBoxValueAttribute: {
TODO(loc, "HLFIR PassBy::CharBoxValueAttribute");
} break;
case PassBy::AddressAndLength:
// PassBy::AddressAndLength is only used for character results. Results
// are not handled here.
fir::emitFatalError(
loc, "unexpected PassBy::AddressAndLength for actual arguments");
break;
case PassBy::CharProcTuple: {
TODO(loc, "HLFIR PassBy::CharProcTuple");
} break;
case PassBy::Box: {
TODO(loc, "HLFIR PassBy::Box");
} break;
case PassBy::MutableBox: {
TODO(loc, "HLFIR PassBy::MutableBox");
} break;
}
}
// Prepare lowered arguments according to the interface
// and map the lowered values to the dummy
// arguments.
fir::ExtendedValue result = Fortran::lower::genCallOpAndResult(
loc, callContext.converter, callContext.symMap, callContext.stmtCtx,
caller, callSiteType, callContext.resultType);
/// Clean-up associations and copy-in.
for (auto associate : exprAssociations)
builder.create<hlfir::EndAssociateOp>(loc, associate);
if (!fir::getBase(result))
return std::nullopt; // subroutine call.
// TODO: "move" non pointer results into hlfir.expr.
return extendedValueToHlfirEntity(loc, builder, result, ".tmp.func_result");
}
/// Lower calls to elemental user procedure with array actual arguments.
static std::optional<hlfir::EntityWithAttributes>
genElementalUserCall(PreparedActualArguments &loweredActuals,
Fortran::lower::CallerInterface &caller,
mlir::FunctionType callSiteType, bool isImpure,
CallContext &callContext) {
using PassBy = Fortran::lower::CallerInterface::PassEntityBy;
mlir::Location loc = callContext.loc;
fir::FirOpBuilder &builder = callContext.getBuilder();
assert(loweredActuals.size() == caller.getPassedArguments().size());
unsigned numArgs = loweredActuals.size();
// Step 1: dereference pointers/allocatables and compute elemental shape.
mlir::Value shape;
// 10.1.4 p5. Impure elemental procedures must be called in element order.
bool mustBeOrdered = isImpure;
for (unsigned i = 0; i < numArgs; ++i) {
const auto &arg = caller.getPassedArguments()[i];
auto &preparedActual = loweredActuals[i];
if (preparedActual) {
hlfir::Entity &actual = preparedActual->actual;
// Elemental procedure dummy arguments cannot be pointer/allocatables
// (C15100), so it is safe to dereference any pointer or allocatable
// actual argument now instead of doing this inside the elemental
// region.
actual = hlfir::derefPointersAndAllocatables(loc, builder, actual);
// Better to load scalars outside of the loop when possible.
if (!preparedActual->handleDynamicOptional &&
(arg.passBy == PassBy::Value ||
arg.passBy == PassBy::BaseAddressValueAttribute))
actual = hlfir::loadTrivialScalar(loc, builder, actual);
// TODO: merge shape instead of using the first one.
if (!shape && actual.isArray()) {
if (preparedActual->handleDynamicOptional)
TODO(loc, "deal with optional with shapes in HLFIR elemental call");
shape = hlfir::genShape(loc, builder, actual);
}
// 15.8.3 p1. Elemental procedure with intent(out)/intent(inout)
// arguments must be called in element order.
if (arg.mayBeModifiedByCall())
mustBeOrdered = true;
}
}
assert(shape &&
"elemental array calls must have at least one array arguments");
if (mustBeOrdered)
TODO(loc, "ordered elemental calls in HLFIR");
if (!callContext.resultType) {
// Subroutine case. Generate call inside loop nest.
auto [innerLoop, oneBasedIndices] = hlfir::genLoopNest(loc, builder, shape);
auto insPt = builder.saveInsertionPoint();
builder.setInsertionPointToStart(innerLoop.getBody());
for (auto &preparedActual : loweredActuals)
if (preparedActual)
preparedActual->actual = hlfir::getElementAt(
loc, builder, preparedActual->actual, oneBasedIndices);
genUserCall(loweredActuals, caller, callSiteType, callContext);
builder.restoreInsertionPoint(insPt);
return std::nullopt;
}
// Function case: generate call inside hlfir.elemental
mlir::Type elementType =
hlfir::getFortranElementType(*callContext.resultType);
// Get result length parameters.
llvm::SmallVector<mlir::Value> typeParams;
if (elementType.isa<fir::CharacterType>() ||
fir::isRecordWithTypeParameters(elementType))
TODO(loc, "compute elemental function result length parameters in HLFIR");
auto genKernel = [&](mlir::Location l, fir::FirOpBuilder &b,
mlir::ValueRange oneBasedIndices) -> hlfir::Entity {
for (auto &preparedActual : loweredActuals)
if (preparedActual)
preparedActual->actual =
hlfir::getElementAt(l, b, preparedActual->actual, oneBasedIndices);
return *genUserCall(loweredActuals, caller, callSiteType, callContext);
};
// TODO: deal with hlfir.elemental result destruction.
return hlfir::EntityWithAttributes{hlfir::genElementalOp(
loc, builder, elementType, shape, typeParams, genKernel)};
}
/// Lower an intrinsic procedure reference.
static hlfir::EntityWithAttributes
genIntrinsicRef(const Fortran::evaluate::SpecificIntrinsic &intrinsic,
CallContext &callContext) {
mlir::Location loc = callContext.loc;
auto &converter = callContext.converter;
auto &stmtCtx = callContext.stmtCtx;
if (Fortran::lower::intrinsicRequiresCustomOptionalHandling(
callContext.procRef, intrinsic, converter))
TODO(loc, "special cases of intrinsic with optional arguments");
if (callContext.isElementalProcWithArrayArgs())
TODO(loc, "lowering elemental intrinsic call to HLFIR");
llvm::SmallVector<fir::ExtendedValue> operands;
// Lower arguments to ... hlfir::Entity.
// Create elem context.
// Call inside code.
const Fortran::lower::IntrinsicArgumentLoweringRules *argLowering =
Fortran::lower::getIntrinsicArgumentLowering(intrinsic.name);
for (const auto &arg : llvm::enumerate(callContext.procRef.arguments())) {
auto *expr =
Fortran::evaluate::UnwrapExpr<Fortran::lower::SomeExpr>(arg.value());
if (!expr) {
// Absent optional.
operands.emplace_back(Fortran::lower::getAbsentIntrinsicArgument());
continue;
}
if (!argLowering) {
// No argument lowering instruction, lower by value.
operands.emplace_back(converter.genExprValue(loc, *expr, stmtCtx));
continue;
}
// Ad-hoc argument lowering handling.
Fortran::lower::ArgLoweringRule argRules =
Fortran::lower::lowerIntrinsicArgumentAs(*argLowering, arg.index());
if (argRules.handleDynamicOptional &&
Fortran::evaluate::MayBePassedAsAbsentOptional(
*expr, converter.getFoldingContext()))
TODO(loc, "intrinsic dynamically optional arguments");
switch (argRules.lowerAs) {
case Fortran::lower::LowerIntrinsicArgAs::Value:
operands.emplace_back(converter.genExprValue(loc, *expr, stmtCtx));
continue;
case Fortran::lower::LowerIntrinsicArgAs::Addr:
operands.emplace_back(converter.genExprAddr(loc, *expr, stmtCtx));
continue;
case Fortran::lower::LowerIntrinsicArgAs::Box:
operands.emplace_back(converter.genExprBox(loc, *expr, stmtCtx));
continue;
case Fortran::lower::LowerIntrinsicArgAs::Inquired:
TODO(loc, "as inquired arguments in HLFIR");
continue;
}
llvm_unreachable("bad switch");
}
// Let the intrinsic library lower the intrinsic procedure call.
fir::ExtendedValue val = Fortran::lower::genIntrinsicCall(
callContext.getBuilder(), loc, intrinsic.name, callContext.resultType,
operands, stmtCtx);
return extendedValueToHlfirEntity(loc, callContext.getBuilder(), val,
".tmp.intrinsic_result");
}
/// Main entry point to lower procedure references, regardless of what they are.
static std::optional<hlfir::EntityWithAttributes>
genProcedureRef(CallContext &callContext) {
mlir::Location loc = callContext.loc;
if (auto *intrinsic = callContext.procRef.proc().GetSpecificIntrinsic())
return genIntrinsicRef(*intrinsic, callContext);
if (callContext.isStatementFunctionCall())
return genStmtFunctionRef(loc, callContext.converter, callContext.symMap,
callContext.stmtCtx, callContext.procRef);
Fortran::lower::CallerInterface caller(callContext.procRef,
callContext.converter);
mlir::FunctionType callSiteType = caller.genFunctionType();
PreparedActualArguments loweredActuals;
// Lower the actual arguments
for (const Fortran::lower::CallInterface<
Fortran::lower::CallerInterface>::PassedEntity &arg :
caller.getPassedArguments())
if (const auto *actual = arg.entity) {
const auto *expr = actual->UnwrapExpr();
if (!expr)
TODO(loc, "assumed type actual argument");
const bool handleDynamicOptional =
arg.isOptional() &&
Fortran::evaluate::MayBePassedAsAbsentOptional(
*expr, callContext.converter.getFoldingContext());
auto loweredActual = Fortran::lower::convertExprToHLFIR(
loc, callContext.converter, *expr, callContext.symMap,
callContext.stmtCtx);
loweredActuals.emplace_back(
PreparedActualArgument{loweredActual, handleDynamicOptional});
} else {
// Optional dummy argument for which there is no actual argument.
loweredActuals.emplace_back(std::nullopt);
}
if (callContext.isElementalProcWithArrayArgs()) {
bool isImpure = false;
if (const Fortran::semantics::Symbol *procSym =
callContext.procRef.proc().GetSymbol())
isImpure = !Fortran::semantics::IsPureProcedure(*procSym);
return genElementalUserCall(loweredActuals, caller, callSiteType, isImpure,
callContext);
}
return genUserCall(loweredActuals, caller, callSiteType, callContext);
}
std::optional<hlfir::EntityWithAttributes> Fortran::lower::convertCallToHLFIR(
mlir::Location loc, Fortran::lower::AbstractConverter &converter,
const evaluate::ProcedureRef &procRef, std::optional<mlir::Type> resultType,
Fortran::lower::SymMap &symMap, Fortran::lower::StatementContext &stmtCtx) {
CallContext callContext(procRef, resultType, loc, converter, symMap, stmtCtx);
return genProcedureRef(callContext);
}