Implement the UNSIGNED extension type and operations under control of a
language feature flag (-funsigned).
This is nearly identical to the UNSIGNED feature that has been available
in Sun Fortran for years, and now implemented in GNU Fortran for
gfortran 15, and proposed for ISO standardization in J3/24-116.txt.
See the new documentation for details; but in short, this is C's
unsigned type, with guaranteed modular arithmetic for +, -, and *, and
the related transformational intrinsic functions SUM & al.
A defined assignment generic interface for a given LHS/RHS type & rank
combination may have a specific procedure with LHS dummy argument that
is neither allocatable nor pointer, or specific procedure(s) whose LHS
dummy arguments are allocatable or pointer. It is possible to have two
specific procedures if one's LHS dummy argument is allocatable and the
other's is pointer.
However, the runtime doesn't work with LHS dummy arguments that are
allocatable, and will crash with a mysterious "invalid descriptor" error
message.
Extend the list of special bindings to include
ScalarAllocatableAssignment and ScalarPointerAssignment, use them when
appropriate in the runtime type information tables, and handle them in
Assign() in the runtime support library.
This is a simplified implementation of std::optional that can be used
in the offload builds for the device code. The methods are properly
marked with RT_API_ATTRS so that the device compilation succedes.
Reviewers: klausler, jeanPerier
Reviewed By: jeanPerier
Pull Request: https://github.com/llvm/llvm-project/pull/85177
Ensure that the f18Addendum flag is preserved in AllocatableApplyMold(),
that raw().type is reinitialized in AllocatableDeallocatePolymorphic(),
and that the implementations of SameTypeAs() and ExtendsTypeOf() handle
unallocated unlimited polymorphic arguments correctly.
When a FINAL subroutine is being invoked for a discontiguous array, which can
happen for INTENT(OUT) dummy arguments and for some left-hand side variables
in intrinsic assignment statements, it may be the case that the subroutine
being called was defined with a dummy argument that requires contiguous data.
Extend the derived type descriptions used by the runtime to signify when
a special procedure binding requires contiguity; set the flags accordingly;
check them in the runtime support library, and, when necessary, use a
temporary shallow copy of the finalized array data in the call to the
final subroutine.
Differential Revision: https://reviews.llvm.org/D156760
Pointer components without default initialization pose some
difficult (or impossible) problems when they appear as right-hand
side targets in pointer assignment statements; they may contain
garbage or stale data that looks enough like a valid descriptor
to cause a crash. Solve the problem by avoiding it -- ensure
that pointers' descriptors are at least minimally established.
Differential Revision: https://reviews.llvm.org/D149979
Extend the descriptor creation function for components to allow
unlimited polymorphic components (CLASS(*)) and to also properly set
the attributes of the established descriptors.
Differential Revision: https://reviews.llvm.org/D140141
A namelist input item that is a derived type component reference
needs additional processing when the base item or the component
is an array. When both have rank > 0, the component reference
must of course be subscripted.
(Fixes https://gitlab-master.nvidia.com/fortran/f18-stage/-/issues/999, NAG test t/tz2.)
The character length value in the derived type component information table
entry is already in units of characters, not bytes, so don't divide by the
per-character byte size.
Differential Revision: https://reviews.llvm.org/D126139
When the runtime is initializing an instance of a derived type,
don't crash if an allocatable character component has deferred length.
Differential Revision: https://reviews.llvm.org/D119731
Component::CreatePointerDescriptor unconditionally expects a
vector of subscripts to be passed as an argument, but is called
from NAMELIST input with a null pointer. Make that argument
a nullable pointer, move it to the end of the argument list,
and give it a default value of nullptr.
Differential Revision: https://reviews.llvm.org/D113312
Define an API for, and implement, runtime support for arbitrary
assignment of one descriptor's data to another, with full support for
(re)allocation of allocatables with finalization when necessary,
user-defined derived type assignment TBP calls, and intrinsic (default)
componentwise assignment of derived type instances with allocation of
automatic components. Also clean up API and implementation of
finalization/destruction using knowledge gained while studying
edge cases for assignment in the 2018 standard.
The look-up procedure for special procedure bindings in derived
types has been optimized from O(N) to O(1) since it will probably
matter more. This required some analysis in runtime derived type
description table construction in semantics and some changes to the
table schemata.
Executable Fortran tests have been developed; they'll be added
to the test base once they can be lowered and run by f18.
Differential Revision: https://reviews.llvm.org/D107678
Use derived type information tables to drive default component
initialization (when needed), component destruction, and calls to
final subroutines. Perform these operations automatically for
ALLOCATE()/DEALLOCATE() APIs for allocatables, automatics, and
pointers. Add APIs for use in lowering to perform these operations
for non-allocatable/automatic non-pointer variables.
Data pointer component initialization supports arbitrary constant
designators, a F'2008 feature, which may be a first for Fortran
implementations.
Differential Revision: https://reviews.llvm.org/D106297
With derived type description tables now available to the
runtime library, it is possible to implement the concept
of "child" I/O statements in the runtime and use them to
convert instances of derived type I/O data transfers into
calls to user-defined subroutines when they have been specified
for a type. (See Fortran 2018, subclauses 12.6.4.8 & 13.7.6).
- Support formatted, list-directed, and NAMELIST
transfers to internal parent units; support these, and unformatted
transfers, for external parent units.
- Support nested child defined derived type I/O.
- Parse DT'foo'(v-list) FORMAT data edit descriptors and passes
their strings &/or v-list values as arguments to the defined
formatted I/O routines.
- Fix problems with this feature encountered in semantics and
FORMAT valiation during development and end-to-end testing.
- Convert typeInfo::SpecialBinding from a struct to a class
after adding a member function.
Differential Revision: https://reviews.llvm.org/D104930
One of the buildbots uses a compiler (can't tell which) that
doesn't approve of a "default:" in a switch statement whose
cases appear to completely cover all possible values of an
enum class. But this switch is in raw data dumping code that
needs to allow for incorrect values in memory. So rewrite it
as a cascade of if statements; performance doesn't matter here.
This is *not* user-defined derived type I/O, but rather Fortran's
built-in capabilities for using derived type data in I/O lists
and NAMELIST groups.
This feature depends on having the derived type description tables
that are created by Semantics available, passed through compilation
as initialized static objects to which pointers can be targeted
in the descriptors of I/O list items and NAMELIST groups.
NAMELIST processing now handles component references on input
(e.g., "&GROUP x%component = 123 /").
The C++ perspectives of the derived type information records
were transformed into proper classes when it was necessary to add
member functions to them.
The code in Semantics that generates derived type information
was changed to emit derived type components in component order,
not alphabetic order.
Differential Revision: https://reviews.llvm.org/D104485