Peter Klausler 21a406c92c
[flang] Improve runtime SAME_TYPE_AS() (#135670)
The present implementation of the intrinsic function SAME_TYPE_AS()
yields false positive .TRUE. results for distinct derived types that
happen to have the same name.

Replace with an implementation that can now depend on derived type
information records being the same type if and only if they are at the
same location, or are PDT instantiations of the same uninstantiated
derived type. And ensure that the derived type information includes
references from instantiated PDTs to their original types. (The derived
type information format supports these references already, but they were
not being set, perhaps because the current faulty SAME_TYPE_AS
implementation didn't need them, and nothing else does.)

Fixes https://github.com/llvm/llvm-project/issues/135580.
2025-04-18 12:48:33 -07:00

160 lines
5.4 KiB
C++

//===-- lib/runtime/derived-api.cpp -----------------------------*- C++ -*-===//
//
// 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/Runtime/derived-api.h"
#include "flang-rt/runtime/derived.h"
#include "flang-rt/runtime/descriptor.h"
#include "flang-rt/runtime/terminator.h"
#include "flang-rt/runtime/tools.h"
#include "flang-rt/runtime/type-info.h"
namespace Fortran::runtime {
extern "C" {
RT_EXT_API_GROUP_BEGIN
void RTDEF(Initialize)(
const Descriptor &descriptor, const char *sourceFile, int sourceLine) {
if (const DescriptorAddendum * addendum{descriptor.Addendum()}) {
if (const auto *derived{addendum->derivedType()}) {
if (!derived->noInitializationNeeded()) {
Terminator terminator{sourceFile, sourceLine};
Initialize(descriptor, *derived, terminator);
}
}
}
}
void RTDEF(InitializeClone)(const Descriptor &clone, const Descriptor &orig,
const char *sourceFile, int sourceLine) {
if (const DescriptorAddendum * addendum{clone.Addendum()}) {
if (const auto *derived{addendum->derivedType()}) {
Terminator terminator{sourceFile, sourceLine};
InitializeClone(clone, orig, *derived, terminator);
}
}
}
void RTDEF(Destroy)(const Descriptor &descriptor) {
if (const DescriptorAddendum * addendum{descriptor.Addendum()}) {
if (const auto *derived{addendum->derivedType()}) {
if (!derived->noDestructionNeeded()) {
// TODO: Pass source file & line information to the API
// so that a good Terminator can be passed
Destroy(descriptor, true, *derived, nullptr);
}
}
}
}
void RTDEF(Finalize)(
const Descriptor &descriptor, const char *sourceFile, int sourceLine) {
if (const DescriptorAddendum * addendum{descriptor.Addendum()}) {
if (const auto *derived{addendum->derivedType()}) {
if (!derived->noFinalizationNeeded()) {
Terminator terminator{sourceFile, sourceLine};
Finalize(descriptor, *derived, &terminator);
}
}
}
}
bool RTDEF(ClassIs)(
const Descriptor &descriptor, const typeInfo::DerivedType &derivedType) {
if (const DescriptorAddendum * addendum{descriptor.Addendum()}) {
if (const auto *derived{addendum->derivedType()}) {
if (derived == &derivedType) {
return true;
}
const typeInfo::DerivedType *parent{derived->GetParentType()};
while (parent) {
if (parent == &derivedType) {
return true;
}
parent = parent->GetParentType();
}
}
}
return false;
}
static RT_API_ATTRS const typeInfo::DerivedType *GetDerivedType(
const Descriptor &desc) {
if (const DescriptorAddendum * addendum{desc.Addendum()}) {
if (const auto *derived{addendum->derivedType()}) {
return derived;
}
}
return nullptr;
}
bool RTDEF(SameTypeAs)(const Descriptor &a, const Descriptor &b) {
auto aType{a.raw().type};
auto bType{b.raw().type};
if ((aType != CFI_type_struct && aType != CFI_type_other) ||
(bType != CFI_type_struct && bType != CFI_type_other)) {
// If either type is intrinsic, they must match.
return aType == bType;
} else if (const typeInfo::DerivedType * derivedTypeA{GetDerivedType(a)}) {
if (const typeInfo::DerivedType * derivedTypeB{GetDerivedType(b)}) {
if (derivedTypeA == derivedTypeB) {
return true;
} else if (const typeInfo::DerivedType *
uninstDerivedTypeA{derivedTypeA->uninstantiatedType()}) {
// There are KIND type parameters, are these the same type if those
// are ignored?
const typeInfo::DerivedType *uninstDerivedTypeB{
derivedTypeB->uninstantiatedType()};
return uninstDerivedTypeA == uninstDerivedTypeB;
}
}
}
return false;
}
bool RTDEF(ExtendsTypeOf)(const Descriptor &a, const Descriptor &mold) {
auto aType{a.raw().type};
auto moldType{mold.raw().type};
if ((aType != CFI_type_struct && aType != CFI_type_other) ||
(moldType != CFI_type_struct && moldType != CFI_type_other)) {
// If either type is intrinsic, they must match.
return aType == moldType;
} else if (const typeInfo::DerivedType *
derivedTypeMold{GetDerivedType(mold)}) {
// If A is unlimited polymorphic and is either a disassociated pointer or
// unallocated allocatable, the result is false.
// Otherwise if the dynamic type of A or MOLD is extensible, the result is
// true if and only if the dynamic type of A is an extension type of the
// dynamic type of MOLD.
for (const typeInfo::DerivedType *derivedTypeA{GetDerivedType(a)};
derivedTypeA; derivedTypeA = derivedTypeA->GetParentType()) {
if (derivedTypeA == derivedTypeMold) {
return true;
}
}
return false;
} else {
// MOLD is unlimited polymorphic and unallocated/disassociated.
return true;
}
}
void RTDEF(DestroyWithoutFinalization)(const Descriptor &descriptor) {
if (const DescriptorAddendum * addendum{descriptor.Addendum()}) {
if (const auto *derived{addendum->derivedType()}) {
if (!derived->noDestructionNeeded()) {
Destroy(descriptor, /*finalize=*/false, *derived, nullptr);
}
}
}
}
RT_EXT_API_GROUP_END
} // extern "C"
} // namespace Fortran::runtime