Peter Klausler 396865576f [flang] Accommodate module subprograms defined in the same module
The symbol table, name resolution, and semantic checks for module
subprograms -- esp. for MODULE FUNCTION and MODULE SUBROUTINE, but
also MODULE PROCEDURE -- essentially assumed that the subprogram
would be defined in a submodule of the (sub)module containing its
interface.  However, it is conforming to instead declare a module
subprogram in the *same* (sub)module as its interface, and we need
to handle that case.

Since this case involves two symbols in the same scope with the same
name, the symbol table details for subprograms have been extended
with a pointer to the original module interface, rather than relying
on searching in scopes.

Differential Revision: https://reviews.llvm.org/D120839
2022-03-02 13:07:16 -08:00

747 lines
22 KiB
C++

//===-- lib/Semantics/symbol.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
//
//===----------------------------------------------------------------------===//
#include "flang/Semantics/symbol.h"
#include "flang/Common/idioms.h"
#include "flang/Evaluate/expression.h"
#include "flang/Semantics/scope.h"
#include "flang/Semantics/semantics.h"
#include "flang/Semantics/tools.h"
#include "llvm/Support/raw_ostream.h"
#include <cstring>
#include <string>
#include <type_traits>
namespace Fortran::semantics {
template <typename T>
static void DumpOptional(llvm::raw_ostream &os, const char *label, const T &x) {
if (x) {
os << ' ' << label << ':' << *x;
}
}
template <typename T>
static void DumpExpr(llvm::raw_ostream &os, const char *label,
const std::optional<evaluate::Expr<T>> &x) {
if (x) {
x->AsFortran(os << ' ' << label << ':');
}
}
static void DumpBool(llvm::raw_ostream &os, const char *label, bool x) {
if (x) {
os << ' ' << label;
}
}
static void DumpSymbolVector(llvm::raw_ostream &os, const SymbolVector &list) {
char sep{' '};
for (const Symbol &elem : list) {
os << sep << elem.name();
sep = ',';
}
}
static void DumpType(llvm::raw_ostream &os, const Symbol &symbol) {
if (const auto *type{symbol.GetType()}) {
os << *type << ' ';
}
}
static void DumpType(llvm::raw_ostream &os, const DeclTypeSpec *type) {
if (type) {
os << ' ' << *type;
}
}
template <typename T>
static void DumpList(llvm::raw_ostream &os, const char *label, const T &list) {
if (!list.empty()) {
os << ' ' << label << ':';
char sep{' '};
for (const auto &elem : list) {
os << sep << elem;
sep = ',';
}
}
}
void SubprogramDetails::set_moduleInterface(Symbol &symbol) {
CHECK(!moduleInterface_);
moduleInterface_ = &symbol;
}
const Scope *ModuleDetails::parent() const {
return isSubmodule_ && scope_ ? &scope_->parent() : nullptr;
}
const Scope *ModuleDetails::ancestor() const {
return isSubmodule_ && scope_ ? FindModuleContaining(*scope_) : nullptr;
}
void ModuleDetails::set_scope(const Scope *scope) {
CHECK(!scope_);
bool scopeIsSubmodule{scope->parent().kind() == Scope::Kind::Module};
CHECK(isSubmodule_ == scopeIsSubmodule);
scope_ = scope;
}
llvm::raw_ostream &operator<<(
llvm::raw_ostream &os, const SubprogramDetails &x) {
DumpBool(os, "isInterface", x.isInterface_);
DumpBool(os, "dummy", x.isDummy_);
DumpOptional(os, "bindName", x.bindName());
if (x.result_) {
DumpType(os << " result:", x.result());
os << x.result_->name();
if (!x.result_->attrs().empty()) {
os << ", " << x.result_->attrs();
}
}
if (x.entryScope_) {
os << " entry";
if (x.entryScope_->symbol()) {
os << " in " << x.entryScope_->symbol()->name();
}
}
char sep{'('};
os << ' ';
for (const Symbol *arg : x.dummyArgs_) {
os << sep;
sep = ',';
if (arg) {
DumpType(os, *arg);
os << arg->name();
} else {
os << '*';
}
}
os << (sep == '(' ? "()" : ")");
if (x.stmtFunction_) {
os << " -> " << x.stmtFunction_->AsFortran();
}
if (x.moduleInterface_) {
os << " moduleInterface: " << *x.moduleInterface_;
}
return os;
}
void EntityDetails::set_type(const DeclTypeSpec &type) {
CHECK(!type_);
type_ = &type;
}
void AssocEntityDetails::set_rank(int rank) { rank_ = rank; }
void EntityDetails::ReplaceType(const DeclTypeSpec &type) { type_ = &type; }
void ObjectEntityDetails::set_shape(const ArraySpec &shape) {
CHECK(shape_.empty());
for (const auto &shapeSpec : shape) {
shape_.push_back(shapeSpec);
}
}
void ObjectEntityDetails::set_coshape(const ArraySpec &coshape) {
CHECK(coshape_.empty());
for (const auto &shapeSpec : coshape) {
coshape_.push_back(shapeSpec);
}
}
ProcEntityDetails::ProcEntityDetails(EntityDetails &&d) : EntityDetails(d) {
if (type()) {
interface_.set_type(*type());
}
}
UseErrorDetails::UseErrorDetails(const UseDetails &useDetails) {
add_occurrence(useDetails.location(), *GetUsedModule(useDetails).scope());
}
UseErrorDetails &UseErrorDetails::add_occurrence(
const SourceName &location, const Scope &module) {
occurrences_.push_back(std::make_pair(location, &module));
return *this;
}
void GenericDetails::AddSpecificProc(
const Symbol &proc, SourceName bindingName) {
specificProcs_.push_back(proc);
bindingNames_.push_back(bindingName);
}
void GenericDetails::set_specific(Symbol &specific) {
CHECK(!specific_);
CHECK(!derivedType_);
specific_ = &specific;
}
void GenericDetails::set_derivedType(Symbol &derivedType) {
CHECK(!specific_);
CHECK(!derivedType_);
derivedType_ = &derivedType;
}
void GenericDetails::AddUse(const Symbol &use) {
CHECK(use.has<UseDetails>());
uses_.push_back(use);
}
const Symbol *GenericDetails::CheckSpecific() const {
return const_cast<GenericDetails *>(this)->CheckSpecific();
}
Symbol *GenericDetails::CheckSpecific() {
if (specific_) {
for (const Symbol &proc : specificProcs_) {
if (&proc == specific_) {
return nullptr;
}
}
return specific_;
} else {
return nullptr;
}
}
void GenericDetails::CopyFrom(const GenericDetails &from) {
CHECK(specificProcs_.size() == bindingNames_.size());
CHECK(from.specificProcs_.size() == from.bindingNames_.size());
kind_ = from.kind_;
if (from.derivedType_) {
CHECK(!derivedType_ || derivedType_ == from.derivedType_);
derivedType_ = from.derivedType_;
}
for (std::size_t i{0}; i < from.specificProcs_.size(); ++i) {
if (std::find_if(specificProcs_.begin(), specificProcs_.end(),
[&](const Symbol &mySymbol) {
return &mySymbol == &*from.specificProcs_[i];
}) == specificProcs_.end()) {
specificProcs_.push_back(from.specificProcs_[i]);
bindingNames_.push_back(from.bindingNames_[i]);
}
}
}
// The name of the kind of details for this symbol.
// This is primarily for debugging.
std::string DetailsToString(const Details &details) {
return std::visit(
common::visitors{
[](const UnknownDetails &) { return "Unknown"; },
[](const MainProgramDetails &) { return "MainProgram"; },
[](const ModuleDetails &) { return "Module"; },
[](const SubprogramDetails &) { return "Subprogram"; },
[](const SubprogramNameDetails &) { return "SubprogramName"; },
[](const EntityDetails &) { return "Entity"; },
[](const ObjectEntityDetails &) { return "ObjectEntity"; },
[](const ProcEntityDetails &) { return "ProcEntity"; },
[](const DerivedTypeDetails &) { return "DerivedType"; },
[](const UseDetails &) { return "Use"; },
[](const UseErrorDetails &) { return "UseError"; },
[](const HostAssocDetails &) { return "HostAssoc"; },
[](const GenericDetails &) { return "Generic"; },
[](const ProcBindingDetails &) { return "ProcBinding"; },
[](const NamelistDetails &) { return "Namelist"; },
[](const CommonBlockDetails &) { return "CommonBlockDetails"; },
[](const TypeParamDetails &) { return "TypeParam"; },
[](const MiscDetails &) { return "Misc"; },
[](const AssocEntityDetails &) { return "AssocEntity"; },
},
details);
}
const std::string Symbol::GetDetailsName() const {
return DetailsToString(details_);
}
void Symbol::set_details(Details &&details) {
CHECK(CanReplaceDetails(details));
details_ = std::move(details);
}
bool Symbol::CanReplaceDetails(const Details &details) const {
if (has<UnknownDetails>()) {
return true; // can always replace UnknownDetails
} else {
return std::visit(
common::visitors{
[](const UseErrorDetails &) { return true; },
[&](const ObjectEntityDetails &) { return has<EntityDetails>(); },
[&](const ProcEntityDetails &) { return has<EntityDetails>(); },
[&](const SubprogramDetails &) {
return has<SubprogramNameDetails>() || has<EntityDetails>();
},
[&](const DerivedTypeDetails &) {
const auto *derived{this->detailsIf<DerivedTypeDetails>()};
return derived && derived->isForwardReferenced();
},
[&](const UseDetails &x) {
const auto *use{this->detailsIf<UseDetails>()};
return use && use->symbol() == x.symbol();
},
[](const auto &) { return false; },
},
details);
}
}
// Usually a symbol's name is the first occurrence in the source, but sometimes
// we want to replace it with one at a different location (but same characters).
void Symbol::ReplaceName(const SourceName &name) {
CHECK(name == name_);
name_ = name;
}
void Symbol::SetType(const DeclTypeSpec &type) {
std::visit(common::visitors{
[&](EntityDetails &x) { x.set_type(type); },
[&](ObjectEntityDetails &x) { x.set_type(type); },
[&](AssocEntityDetails &x) { x.set_type(type); },
[&](ProcEntityDetails &x) { x.interface().set_type(type); },
[&](TypeParamDetails &x) { x.set_type(type); },
[](auto &) {},
},
details_);
}
template <typename T>
constexpr bool HasBindName{std::is_convertible_v<T, const WithBindName *>};
const std::string *Symbol::GetBindName() const {
return std::visit(
[&](auto &x) -> const std::string * {
if constexpr (HasBindName<decltype(&x)>) {
return x.bindName();
} else {
return nullptr;
}
},
details_);
}
void Symbol::SetBindName(std::string &&name) {
std::visit(
[&](auto &x) {
if constexpr (HasBindName<decltype(&x)>) {
x.set_bindName(std::move(name));
} else {
DIE("bind name not allowed on this kind of symbol");
}
},
details_);
}
bool Symbol::IsFuncResult() const {
return std::visit(
common::visitors{[](const EntityDetails &x) { return x.isFuncResult(); },
[](const ObjectEntityDetails &x) { return x.isFuncResult(); },
[](const ProcEntityDetails &x) { return x.isFuncResult(); },
[](const HostAssocDetails &x) { return x.symbol().IsFuncResult(); },
[](const auto &) { return false; }},
details_);
}
bool Symbol::IsObjectArray() const {
const auto *details{std::get_if<ObjectEntityDetails>(&details_)};
return details && details->IsArray();
}
bool Symbol::IsSubprogram() const {
return std::visit(
common::visitors{
[](const SubprogramDetails &) { return true; },
[](const SubprogramNameDetails &) { return true; },
[](const GenericDetails &) { return true; },
[](const UseDetails &x) { return x.symbol().IsSubprogram(); },
[](const auto &) { return false; },
},
details_);
}
bool Symbol::IsFromModFile() const {
return test(Flag::ModFile) ||
(!owner_->IsTopLevel() && owner_->symbol()->IsFromModFile());
}
ObjectEntityDetails::ObjectEntityDetails(EntityDetails &&d)
: EntityDetails(d) {}
llvm::raw_ostream &operator<<(llvm::raw_ostream &os, const EntityDetails &x) {
DumpBool(os, "dummy", x.isDummy());
DumpBool(os, "funcResult", x.isFuncResult());
if (x.type()) {
os << " type: " << *x.type();
}
DumpOptional(os, "bindName", x.bindName());
return os;
}
llvm::raw_ostream &operator<<(
llvm::raw_ostream &os, const ObjectEntityDetails &x) {
os << *static_cast<const EntityDetails *>(&x);
DumpList(os, "shape", x.shape());
DumpList(os, "coshape", x.coshape());
DumpExpr(os, "init", x.init_);
return os;
}
llvm::raw_ostream &operator<<(
llvm::raw_ostream &os, const AssocEntityDetails &x) {
os << *static_cast<const EntityDetails *>(&x);
if (auto assocRank{x.rank()}) {
os << " rank: " << *assocRank;
}
DumpExpr(os, "expr", x.expr());
return os;
}
llvm::raw_ostream &operator<<(
llvm::raw_ostream &os, const ProcEntityDetails &x) {
if (auto *symbol{x.interface_.symbol()}) {
os << ' ' << symbol->name();
} else {
DumpType(os, x.interface_.type());
}
DumpOptional(os, "bindName", x.bindName());
DumpOptional(os, "passName", x.passName());
if (x.init()) {
if (const Symbol * target{*x.init()}) {
os << " => " << target->name();
} else {
os << " => NULL()";
}
}
return os;
}
llvm::raw_ostream &operator<<(
llvm::raw_ostream &os, const DerivedTypeDetails &x) {
DumpBool(os, "sequence", x.sequence_);
DumpList(os, "components", x.componentNames_);
return os;
}
llvm::raw_ostream &operator<<(llvm::raw_ostream &os, const GenericDetails &x) {
os << ' ' << x.kind().ToString();
DumpBool(os, "(specific)", x.specific() != nullptr);
DumpBool(os, "(derivedType)", x.derivedType() != nullptr);
if (const auto &uses{x.uses()}; !uses.empty()) {
os << " (uses:";
char sep{' '};
for (const Symbol &use : uses) {
const Symbol &ultimate{use.GetUltimate()};
os << sep << ultimate.name() << "->"
<< ultimate.owner().GetName().value();
sep = ',';
}
os << ')';
}
os << " procs:";
DumpSymbolVector(os, x.specificProcs());
return os;
}
llvm::raw_ostream &operator<<(llvm::raw_ostream &os, const Details &details) {
os << DetailsToString(details);
std::visit( //
common::visitors{
[&](const UnknownDetails &) {},
[&](const MainProgramDetails &) {},
[&](const ModuleDetails &x) {
if (x.isSubmodule()) {
os << " (";
if (x.ancestor()) {
auto ancestor{x.ancestor()->GetName().value()};
os << ancestor;
if (x.parent()) {
auto parent{x.parent()->GetName().value()};
if (ancestor != parent) {
os << ':' << parent;
}
}
}
os << ")";
}
},
[&](const SubprogramNameDetails &x) {
os << ' ' << EnumToString(x.kind());
},
[&](const UseDetails &x) {
os << " from " << x.symbol().name() << " in "
<< GetUsedModule(x).name();
},
[&](const UseErrorDetails &x) {
os << " uses:";
char sep{':'};
for (const auto &[location, module] : x.occurrences()) {
os << sep << " from " << module->GetName().value() << " at "
<< location;
sep = ',';
}
},
[](const HostAssocDetails &) {},
[&](const ProcBindingDetails &x) {
os << " => " << x.symbol().name();
DumpOptional(os, "passName", x.passName());
},
[&](const NamelistDetails &x) {
os << ':';
DumpSymbolVector(os, x.objects());
},
[&](const CommonBlockDetails &x) {
DumpOptional(os, "bindName", x.bindName());
if (x.alignment()) {
os << " alignment=" << x.alignment();
}
os << ':';
for (const auto &object : x.objects()) {
os << ' ' << object->name();
}
},
[&](const TypeParamDetails &x) {
DumpOptional(os, "type", x.type());
os << ' ' << common::EnumToString(x.attr());
DumpExpr(os, "init", x.init());
},
[&](const MiscDetails &x) {
os << ' ' << MiscDetails::EnumToString(x.kind());
},
[&](const auto &x) { os << x; },
},
details);
return os;
}
llvm::raw_ostream &operator<<(llvm::raw_ostream &o, Symbol::Flag flag) {
return o << Symbol::EnumToString(flag);
}
llvm::raw_ostream &operator<<(
llvm::raw_ostream &o, const Symbol::Flags &flags) {
std::size_t n{flags.count()};
std::size_t seen{0};
for (std::size_t j{0}; seen < n; ++j) {
Symbol::Flag flag{static_cast<Symbol::Flag>(j)};
if (flags.test(flag)) {
if (seen++ > 0) {
o << ", ";
}
o << flag;
}
}
return o;
}
llvm::raw_ostream &operator<<(llvm::raw_ostream &os, const Symbol &symbol) {
os << symbol.name();
if (!symbol.attrs().empty()) {
os << ", " << symbol.attrs();
}
if (!symbol.flags().empty()) {
os << " (" << symbol.flags() << ')';
}
if (symbol.size_) {
os << " size=" << symbol.size_ << " offset=" << symbol.offset_;
}
os << ": " << symbol.details_;
return os;
}
#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
void Symbol::dump() const { llvm::errs() << *this << '\n'; }
#endif
// Output a unique name for a scope by qualifying it with the names of
// parent scopes. For scopes without corresponding symbols, use the kind
// with an index (e.g. Block1, Block2, etc.).
static void DumpUniqueName(llvm::raw_ostream &os, const Scope &scope) {
if (!scope.IsTopLevel()) {
DumpUniqueName(os, scope.parent());
os << '/';
if (auto *scopeSymbol{scope.symbol()};
scopeSymbol && !scopeSymbol->name().empty()) {
os << scopeSymbol->name();
} else {
int index{1};
for (auto &child : scope.parent().children()) {
if (child == scope) {
break;
}
if (child.kind() == scope.kind()) {
++index;
}
}
os << Scope::EnumToString(scope.kind()) << index;
}
}
}
// Dump a symbol for UnparseWithSymbols. This will be used for tests so the
// format should be reasonably stable.
llvm::raw_ostream &DumpForUnparse(
llvm::raw_ostream &os, const Symbol &symbol, bool isDef) {
DumpUniqueName(os, symbol.owner());
os << '/' << symbol.name();
if (isDef) {
if (!symbol.attrs().empty()) {
os << ' ' << symbol.attrs();
}
if (!symbol.flags().empty()) {
os << " (" << symbol.flags() << ')';
}
os << ' ' << symbol.GetDetailsName();
DumpType(os, symbol.GetType());
}
return os;
}
const DerivedTypeSpec *Symbol::GetParentTypeSpec(const Scope *scope) const {
if (const Symbol * parentComponent{GetParentComponent(scope)}) {
const auto &object{parentComponent->get<ObjectEntityDetails>()};
return &object.type()->derivedTypeSpec();
} else {
return nullptr;
}
}
const Symbol *Symbol::GetParentComponent(const Scope *scope) const {
if (const auto *dtDetails{detailsIf<DerivedTypeDetails>()}) {
if (const Scope * localScope{scope ? scope : scope_}) {
return dtDetails->GetParentComponent(DEREF(localScope));
}
}
return nullptr;
}
void DerivedTypeDetails::add_component(const Symbol &symbol) {
if (symbol.test(Symbol::Flag::ParentComp)) {
CHECK(componentNames_.empty());
}
componentNames_.push_back(symbol.name());
}
const Symbol *DerivedTypeDetails::GetParentComponent(const Scope &scope) const {
if (auto extends{GetParentComponentName()}) {
if (auto iter{scope.find(*extends)}; iter != scope.cend()) {
if (const Symbol & symbol{*iter->second};
symbol.test(Symbol::Flag::ParentComp)) {
return &symbol;
}
}
}
return nullptr;
}
const Symbol *DerivedTypeDetails::GetFinalForRank(int rank) const {
for (const auto &pair : finals_) {
const Symbol &symbol{*pair.second};
if (const auto *details{symbol.detailsIf<SubprogramDetails>()}) {
if (details->dummyArgs().size() == 1) {
if (const Symbol * arg{details->dummyArgs().at(0)}) {
if (const auto *object{arg->detailsIf<ObjectEntityDetails>()}) {
if (rank == object->shape().Rank() || object->IsAssumedRank() ||
symbol.attrs().test(Attr::ELEMENTAL)) {
return &symbol;
}
}
}
}
}
}
return nullptr;
}
void TypeParamDetails::set_type(const DeclTypeSpec &type) {
CHECK(!type_);
type_ = &type;
}
bool GenericKind::IsIntrinsicOperator() const {
return Is(OtherKind::Concat) || Has<common::LogicalOperator>() ||
Has<common::NumericOperator>() || Has<common::RelationalOperator>();
}
bool GenericKind::IsOperator() const {
return IsDefinedOperator() || IsIntrinsicOperator();
}
std::string GenericKind::ToString() const {
return std::visit(
common::visitors {
[](const OtherKind &x) { return EnumToString(x); },
[](const DefinedIo &x) { return AsFortran(x).ToString(); },
#if !__clang__ && __GNUC__ == 7 && __GNUC_MINOR__ == 2
[](const common::NumericOperator &x) {
return common::EnumToString(x);
},
[](const common::LogicalOperator &x) {
return common::EnumToString(x);
},
[](const common::RelationalOperator &x) {
return common::EnumToString(x);
},
#else
[](const auto &x) { return common::EnumToString(x); },
#endif
},
u);
}
SourceName GenericKind::AsFortran(DefinedIo x) {
const char *name{nullptr};
switch (x) {
SWITCH_COVERS_ALL_CASES
case DefinedIo::ReadFormatted:
name = "read(formatted)";
break;
case DefinedIo::ReadUnformatted:
name = "read(unformatted)";
break;
case DefinedIo::WriteFormatted:
name = "write(formatted)";
break;
case DefinedIo::WriteUnformatted:
name = "write(unformatted)";
break;
}
return {name, std::strlen(name)};
}
bool GenericKind::Is(GenericKind::OtherKind x) const {
const OtherKind *y{std::get_if<OtherKind>(&u)};
return y && *y == x;
}
bool SymbolOffsetCompare::operator()(const SymbolRef &x, const SymbolRef &y) const {
const Symbol *xCommon{FindCommonBlockContaining(*x)};
const Symbol *yCommon{FindCommonBlockContaining(*y)};
if (xCommon) {
if (yCommon) {
const SymbolSourcePositionCompare sourceCmp;
if (sourceCmp(*xCommon, *yCommon)) {
return true;
} else if (sourceCmp(*yCommon, *xCommon)) {
return false;
} else if (x->offset() == y->offset()) {
return x->size() > y->size();
} else {
return x->offset() < y->offset();
}
} else {
return false;
}
} else if (yCommon) {
return true;
} else if (x->offset() == y->offset()) {
return x->size() > y->size();
} else {
return x->offset() < y->offset();
}
return x->GetSemanticsContext().allCookedSources().Precedes(
x->name(), y->name());
}
bool SymbolOffsetCompare::operator()(
const MutableSymbolRef &x, const MutableSymbolRef &y) const {
return (*this)(SymbolRef{*x}, SymbolRef{*y});
}
} // namespace Fortran::semantics