Commit Graph

12 Commits

Author SHA1 Message Date
V Donaldson
1e1f60c605 [flang] Alternate entry points with unused arguments
A dummy argument in an entry point of a subprogram with multiple
entry points need not be defined in other entry points. It is only
legal to reference such an argument when calling an entry point that
does have a definition. An entry point without such a definition
needs a local "substitute" definition sufficient to generate code.
It is nonconformant to reference such a definition at runtime.
Most such definitions and associated code will be deleted as dead
code at compile time. However, that is not always possible, as in
the following code. This code is conformant if all calls to entry
point ss set m=3, and all calls to entry point ee set n=3.

subroutine ss(a, b, m, d, k) ! no x, y, n
  integer :: a(m), b(a(m)), m, d(k)
  integer :: x(n), y(x(n)), n
  integer :: k
1 print*, m, k
  print*, a
  print*, b
  print*, d
  if (m == 3) return
entry ee(x, y, n, d, k) ! no a, b, m
  print*, n, k
  print*, x
  print*, y
  print*, d
  if (n /= 3) goto 1
end

  integer :: xx(3), yy(5), zz(3)
  xx = 5
  yy = 7
  zz = 9
  call ss(xx, yy, 3, zz, 3)
  call ss(xx, yy, 3, zz, 3)
end

Lowering currently generates fir::UndefOp's for all unused arguments.
This is usually ok, but cases such as the one here incorrectly access
unused UndefOp arguments for m and n from an entry point that doesn't
have a proper definition.

The problem is addressed by creating a more complete definition of an
unused argument in most cases. This is implemented in large part by
moving the definition of an unused argument from mapDummiesAndResults
to mapSymbolAttributes. The code in mapSymbolAttributes then chooses
one of three code generation options, depending on information
available there.

This patch deals with dummy procedures in alternate entries, and adds
a TODO for procedure pointers (the PFTBuilder is modified to analyze
procedure pointer symbol so that they are not silently ignored, and
instead hits proper TODOs).

BoxAnalyzer is also changed because assumed-sized arrays were wrongfully
categorized as constant shape arrays.  This had no impact, except when
there were unused entry points.

Co-authored-by: jeanPerier <jperier@nvidia.com>

Differential Revision: https://reviews.llvm.org/D125867
2022-05-24 10:56:04 -07:00
Jean Perier
2c8cb9acb5 [flang] Handle common block with different sizes in same file
Semantics is not preventing a named common block to appear with
different size in a same file (named common block should always have
the same storage size (see Fortran 2018 8.10.2.5), but it is a common
extension to accept different sizes).

Lowering was not coping with this well, since it just use the first
common block appearance, starting with BLOCK DATAs to define common
blocks (this also was an issue with the blank common block, which can
legally appear with different size in different scoping units).

Semantics is also not preventing named common from being initialized
outside of a BLOCK DATA, and lowering was dealing badly with this,
since it only gave an initial value to common blocks Globals if the
first common block appearance, starting with BLOCK DATAs had an initial
value.

Semantics is also allowing blank common to be initialized, while
lowering was assuming this would never happen, and was never creating
an initial value for it.

Lastly, semantics was not complaining if a COMMON block was initialized
in several scoping unit in a same file, while lowering can only generate
one of these initial value.

To fix this, add a structure to keep track of COMMON block properties
(biggest size, and initial value if any) at the Program level. Once the
size of a common block appearance is know, the common block appearance
is checked against this information. It allows semantics to emit an error
in case of multiple initialization in different scopes of a same common
block, and to warn in case named common blocks appears with different
sizes. Lastly, this allows lowering to use the Program level info about
common blocks to emit the right GlobalOp for a Common Block, regardless
of the COMMON Block appearances order: It emits a GlobalOp with the
biggest size, whose lowest bytes are initialized with the initial value
if any is given in a scope where the common block appears.

Lowering is updated to go emit the common blocks before anything else so
that the related GlobalOps are available when lowering the scopes where
common block appear. It is also updated to not assume that blank common
are never initialized.

Differential Revision: https://reviews.llvm.org/D124622
2022-04-29 14:52:47 +02:00
Kiran Chandramohan
acd75440c6 [Flang] Lower the FailImage Statement
Lowering of FailImage statement generates a runtime call and the
unreachable operation. The unreachable operation cannot terminate
a structured operation like the IF operation, hence  mark as
unstructured.

Note: This patch is part of upstreaming code from the fir-dev branch of
https://github.com/flang-compiler/f18-llvm-project.

Reviewed By: clementval

Differential Revision: https://reviews.llvm.org/D124520

Co-authored-by: Eric Schweitz <eschweitz@nvidia.com>
2022-04-27 12:20:25 +00:00
Peixin-Qiao
f2ac513812 [flang] Fix processing ModuleLikeUnit evaluationList
Push the ModuleLikeUnit evalutionList when entering module unit. Pop it
when exiting module unit if there is no module procedure. Otherwise, pop
it when entering the first module procedure.

Reviewed By: V Donaldson

Differential Revision: https://reviews.llvm.org/D120460
2022-03-11 15:20:23 +08:00
Peixin-Qiao
b905864845 [flang] Support for dump OpenMP/OpenACC declarative directives PFT in module
OpenMP/OpenACC declarative directives can also be used in module unit.
Add support for dump them in module.

Reviewed By: kiranchandramohan, V Donaldson

Differential Revision: https://reviews.llvm.org/D120459
2022-03-11 14:33:17 +08:00
Valentin Clement
026a43f6cf [flang] Update PFTBuilder
This patch update the PFTBuilder to be able to lower
the construct present in semantics.

This is a building block for other lowering patches that will be posted soon.

This patch is part of the upstreaming effort from fir-dev branch.

Reviewed By: PeteSteinfeld, schweitz

Differential Revision: https://reviews.llvm.org/D120336

Co-authored-by: Jean Perier <jperier@nvidia.com>
Co-authored-by: V Donaldson <vdonaldson@nvidia.com>
2022-02-22 19:09:28 +01:00
Nico Weber
861eff24df [flang] iwyu fixes after ba7a92c01e 2021-04-21 11:10:45 -04:00
Eric Schweitz
987ee6e3cc [flang][fir] Upstream the pre-FIR tree changes.
The PFT has been updated to support Fortran 77.
clang-tidy cleanup.

Authors: Val Donaldson, Jean Perier, Eric Schweitz, et.al.

Differential Revision: https://reviews.llvm.org/D98283
2021-03-10 07:45:58 -08:00
Michael Kruse
b656189e6a [flang][msvc] Avoid ReferenceVariantBase ctor ambiguity. NFC.
Msvc reports the following error when a ReferenceVariantBase is constructed using an r-value reference or instantiated as std::vector template parameter.  The error message is:
```
PFTBuilder.h(59,1): error C2665: 'std::variant<...>::variant': none of the 2 overloads could convert all the argument types
variant(1248,1): message : could be 'std::variant<...>::variant(std::variant<...> &&) noexcept(false)'
variant(1248,1): message : or       'std::variant<...>::variant(const std::variant<...> &) noexcept(false)'
PFTBuilder.h(59,1): message : while trying to match the argument list '(common::Reference<lower::pft::ReferenceVariantBase<false,...>>)'
```

Work around the ambiguity by only taking `common::Reference` arguments in the constructor. That is, conversion to common::Reference has to be done be the caller instead of being done inside the ctor. Unfortunately, with this change clang/gcc (but not msvc) insist on that the ReferenceVariantBase is stored in a `std::initializer_list`-initialized variable before being used, like being passed to a function or returned.

This patch is part of the series to make flang compilable with MS Visual Studio <http://lists.llvm.org/pipermail/flang-dev/2020-July/000448.html>.

Reviewed By: DavidTruby

Differential Revision: https://reviews.llvm.org/D88109
2020-09-30 20:54:09 -05:00
Eric Schweitz
c3477c51e5 [flang] Add CHARACTER type lowering helpers and runtime.
In order for these files to build properly, this patch rolls up a number of changes that have been made to various files that have been upstreamed.

Implementations for the interfaces included in Bridge.h and IntrinsicCall.h will be included in a future diff.

Differential revision: https://reviews.llvm.org/D82608
2020-06-26 11:01:52 -07:00
Eric Schweitz
fbac9ce226 [flang] Batch together the changes to the PFT intermediate data
structure for upstreaming to llvm-project.

These files have had many changes since they were originally upstreamed.
Some of the changes are cosmetic.  Most of the functional changes were
done to support the lowering of control-flow syntax from the front-end
parse trees to the FIR dialect.

This patch is meant to be a reviewable size. The functionality it
provides will be used by code yet to be upstreamed in lowering.

review comments:

[review D80449][NFC] make PFT ParentVariant a ReferenceVariant

ReferenceVariant had to be slightly updated to also support
non constant references (which is required for ParentType).

[review D80449] extend Variable implementation beyond a comment
2020-05-29 15:24:20 -07:00
CarolineConcatto
64ab3302d5 [flang] [LLVMify F18] Compiler module folders should have capitalised names (flang-compiler/f18#980)
This patch renames the modules in f18 to use a capital letter in the
module name

Signed-off-by: Caroline Concatto <caroline.concatto@arm.com>

Original-commit: flang-compiler/f18@d2eb7a1c44
Reviewed-on: https://github.com/flang-compiler/f18/pull/980
2020-02-25 07:11:52 -08:00