Commit Graph

627 Commits

Author SHA1 Message Date
Kazu Hirata a8c294d6aa [flang] Remove redundant string initialization (NFC)
Identified with readability-redundant-string-init.
2022-08-14 12:52:01 -07:00
Nimish Mishra 435feefbdd [flang][OpenMP] Lowering support for default clause
This patch adds lowering support for default clause.

1. During symbol resolution in semantics, should the enclosing context
   have a default data sharing clause defined and a `parser::Name` is not
   attached to an explicit data sharing clause, the
   `semantics::Symbol::Flag::OmpPrivate` flag (in case of
   default(private)) and `semantics::Symbol::Flag::OmpFirstprivate` flag
   (in case of default(firstprivate)) is added to the symbol.

2. During lowering, all symbols having either
   `semantics::Symbol::Flag::OmpPrivate` or
   `semantics::Symbol::Flag::OmpFirstprivate` flag are collected and
   privatised appropriately.

Co-authored-by: Peixin Qiao <qiaopeixin@huawei.com>

Reviewed by: peixin

Differential Revision: https://reviews.llvm.org/D123930
2022-08-12 16:46:26 +05:30
Nimish Mishra 30b779d515 Revert "[flang][OpenMP] Lowering support for default clause"
This reverts commit 6a305c9b49.
2022-08-12 16:45:38 +05:30
Nimish Mishra 6a305c9b49 [flang][OpenMP] Lowering support for default clause
This patch adds lowering support for default clause.

1. During symbol resolution in semantics, should the enclosing context have
a default data sharing clause defined and a `parser::Name` is not attached
to an explicit data sharing clause, the
`semantics::Symbol::Flag::OmpPrivate` flag (in case of default(private))
and `semantics::Symbol::Flag::OmpFirstprivate` flag (in case of
default(firstprivate)) is added to the symbol.

2. During lowering, all symbols having either
`semantics::Symbol::Flag::OmpPrivate` or
`semantics::Symbol::Flag::OmpFirstprivate` flag are collected and
privatised appropriately.

Co-authored-by: Peixin Qiao <qiaopeixin@huawei.com>

Reviewed by: peixin

Differential Revision: https://reviews.llvm.org/D123930
2022-08-12 22:08:14 +05:30
Peter Klausler 46c49e66d8 [flang] Extend characterization & checking for procedure bindings
Procedure bindings with explicit interfaces don't work when the
interface is shadowed by a generic interface of the same name,
and can produce spurious semantic error messages.  Extend the
characterization and checking code for such things, and the utility
functionns on which they depend, to dig through generics when they
occlude interface-defining subprograms.  This is done on demand in
checking code, not once during name resolution, because the
procedures in question may also be forward-referenced.

Differential Revision: https://reviews.llvm.org/D131105

diff --git a/flang/include/flang/Semantics/symbol.h b/flang/include/flang/Semantics/symbol.h
index e79f8ab6503e..0b03bf06eb73 100644
--- a/flang/include/flang/Semantics/symbol.h
2022-08-09 12:01:45 -07:00
Peter Klausler bad5205595 [flang][runtime] Support internal I/O to CHARACTER(KIND/=1)
Allow internal I/O to support non-default kinds of CHARACTER.

The I/O runtime design anticipated this standard feature, but
this patch is somewhat larger than I thought it would be because
many code sites had to have assumptions about units (characters
vs. bytes) brought into harmony, and some encoding utilities
had to be pulled out of IoStatementState and templatized into
their own new header file so that they are available to formatted
output code without having to "thread" an IoStatementState reference
through many call chains.

Differential Revision: https://reviews.llvm.org/D131107
2022-08-09 08:46:21 -07:00
Peter Klausler 525ff9bd20 [flang] Don't check procedure pointer interface function result specification expressions
When a procedure pointer references a function as its interface, don't
apply semantic checks to the specification expressions that appear in
the declaration of the function's result -- this can lead to bogus
error messages as those specification expressions are being examined
out of their proper context.

Differential Revision: https://reviews.llvm.org/D131106
2022-08-09 08:45:32 -07:00
Peter Klausler 5e8094bae5 [flang] Don't inherit ELEMENTAL attribute from intrinsics for TBP bindings
Type-bound procedure bindings that specify intrinsic procedures as their
interfaces should not acquire the ELEMENTAL attribute from the purposes
of compatibility checking between inherited bindings and their overrides
in extended derived types.

Differential Revision: https://reviews.llvm.org/D131104
2022-08-09 08:09:32 -07:00
Peter Klausler 37a0022aaa [flang] Don't lose homonymous specific when copying generic
Defined generic procedure interfaces are allowed to shadow non-generic
procedures of the same name in the same scope (whether or not
that non-generic procedure is a specific procedure of the generic).
When making a copy of a generic interface symbol so that it can
be locally modified or be merged with another generic, don't forget
about the homonymous non-generic procedure that it might shadow.

Differential Revision: https://reviews.llvm.org/D131103
2022-08-09 07:44:52 -07:00
Peter Klausler e1ee20d574 [flang] Ignore inaccessible components when extending types or constructing structures
Inaccessible components -- those declared PRIVATE in another module -- should
be allowed to be redeclared in extended types, and should be ignored if
they appear as keywords in structure constructors.

Differential Revision: https://reviews.llvm.org/D131102
2022-08-09 07:44:02 -07:00
Peter Klausler b8641bfc4c [flang] Don't compute pointer component procedure characteristics when not needed
When a procedure pointer component has an interface that is a forward
reference to a procedure, syntax errors can be emitted if there is
a structure constructor that tries to initialize that component,
since its characteristics are not yet known; however, when the
initializer is a bare NULL(with no mold), those characteristics
don't matter.  Make the characterization of the procedure pointer
component take place only when needed.

Differential Revision: https://reviews.llvm.org/D131100
2022-08-08 15:59:12 -07:00
Peter Klausler e6373de53d [flang] Allow assignment to host association in BLOCK in PURE subprogram
We need to distinguish BLOCK host association from subprogram host
association when checking assignments in PURE subprograms.
The specific case that is not allowed is an assignment to a variable
from the scope around the PURE subprogram.

Differential Revision: https://reviews.llvm.org/D131098
2022-08-07 14:48:53 -07:00
Peter Klausler 3f10091c04 [flang] Allow pure function references in expandable scalar
F18 disallows function references and coarray references from
appearing in scalar expressions that are to be expanded into
arrays to conform with other operands or actual arguments in
an elemental expression.  This is too strong, as pure procedures
can be safely used.

Differential Revision: https://reviews.llvm.org/D131096
2022-08-07 09:12:46 -07:00
Peixin Qiao 48b6f5c708 [flang] Add some semantic checks for derived type with BIND attribute
This supports checks in C1801-C1805 for derived type with BIND attribute.
The other compilers such as 'gfortran' and 'ifort' do not report error
for C1802 and C1805, so emit warnings for them.

Reviewed By: klausler

Differential Revision: https://reviews.llvm.org/D130438
2022-08-02 23:07:02 +08:00
Shraiysh Vaishay f2b7f18e63 Revert "[flang][OpenMP] Lowering support for default clause"
This reverts commit 05e6fce84f.
2022-07-26 19:18:27 +05:30
Nimish Mishra 05e6fce84f [flang][OpenMP] Lowering support for default clause
This patch adds lowering support for default clause.

1. During symbol resolution in semantics, should the enclosing context have
a default data sharing clause defined and a `parser::Name` is not attached
to an explicit data sharing clause, the
`semantics::Symbol::Flag::OmpPrivate` flag (in case of `default(private)`)
and `semantics::Symbol::Flag::OmpFirstprivate` flag (in case of
`default(firstprivate)`) is added to the symbol.

2. During lowering, all symbols having either
   `semantics::Symbol::Flag::OmpPrivate` or
   `semantics::Symbol::Flag::OmpFirstprivate` flag are collected and
   privatised appropriately.

Co-authored-by: Peixin Qiao <qiaopeixin@huawei.com>

Reviewed By: kiranchandramohan

Differential Revision: https://reviews.llvm.org/D123930
2022-07-26 14:11:43 +05:30
Peter Klausler 95f4ca7f5d [flang] Allow restricted specific intrinsic functions as implicitly-interfaced procedure pointer targets
The predicate "CanBeCalledViaImplicitInterface()" was returning false for
restricted specific intrinsic functions (e.g., SIN) because their procedure
characteristics have the elemental attribute; this leads to a bogus semantic
error when one attempts to use them as proc-targets in procedure pointer
assignment statements when the left-hand side of the assignment is a procedure
pointer with an implicit interface.  However, these restricted specific intrinsic
functions have always been allowed as special cases for such usage -- it is
as if they are elemental when it is necessary for them to be so, but not
when it's a problem.

Differential Revision: https://reviews.llvm.org/D130386
2022-07-25 12:19:49 -07:00
Peter Klausler 85a40ce6dd [flang] Better error message for NULL() actual argument for dummy allocatable
f18 intentionally does not support the spottily-implemented language extension
in which one can pass NULL() for an allocatable dummy argument.  This is perhaps
a sanctioned side effect in other compilers of the fact that they pass distinct
"base address" and "descriptor address" physical arguments.

Make the error message in this case more specific to the circumstances, and
add a note to Extensions.md to clarify that this behavior is intended.

(We could, with some effort in lowering, support passing NULL for an INTENT(IN)
allocatable dummy, but let's see whether such nonconforming usage appears
in a real application before spending any more time on it.)

Differential Revision: https://reviews.llvm.org/D130380
2022-07-25 10:09:55 -07:00
Peter Klausler a9782fead3 [flang] Correct IsHostAssociated() to be true for BLOCK constructs
The predicate IsHostAssocited() was implemented in a way that would
return true only for cases of host association into a module or inner
subprogram.  Technically, the use of a name in a BLOCK construct
that is not declared therein is considered in the Fortran standard
to also be a form of host association, and this matters when doing
error checking on DATA statements.

Differential Revision: https://reviews.llvm.org/D130388
2022-07-23 10:46:54 -07:00
Kazu Hirata 7aa77c5a67 [flang] Fix a warning
This patch fixes:

  llvm-project/flang/lib/Semantics/expression.cpp:405:12: error:
  moving a local object in a return statement prevents copy elision
  [-Werror,-Wpessimizing-move]
2022-07-22 17:56:10 -07:00
Peter Klausler e03664d40c [flang] Fix parsing and semantics for array element substring%KIND/%LEN
A type-param-inquiry of %KIND or %LEN applies to a designator, and
so must also be allowed for a substring.  F18 presently (mis)parses
instances of a type-param-inquiry as structure component references
and then fixes them in expression semantics when types are known and
we can distinguish them.  But when the base of a type-param-inquiry is
a substring of an array element, as in "charArray(i)(j:k)%len",
parsing fails.

Adjust the grammar to parse these cases, and extend expression semantics
to process the new production.

Differential Revision: https://reviews.llvm.org/D130375
2022-07-22 16:54:46 -07:00
Peter Klausler c105d9b3d6 [flang] Admit trailing blanks when checking I/O specifiers
Fortran specifically allows character-valued I/O specifiers
to have trailing blanks, e.g. OPEN(666,STATUS='SCRATCH ').
The runtime I/O library already handles them, but the I/O
static checks in semantics do not.

Differential Revision: https://reviews.llvm.org/D130381
2022-07-22 16:21:32 -07:00
Kazu Hirata 8b3ed1fa98 Remove redundant return statements (NFC)
Identified with readability-redundant-control-flow.
2022-07-17 15:37:46 -07:00
Nimish Mishra 7dc18a62e4 [flang][OpenMP] Added semantic checks for hint clause
This patch improves semantic checks for hint clause.
It checks "hint-expression is a constant expression
that evaluates to a scalar value with kind
`omp_sync_hint_kind` and a value that is a valid
synchronization hint."

Reviewed By: peixin

Differential Revision: https://reviews.llvm.org/D127615
2022-07-14 18:24:57 +05:30
Peter Klausler b7f8314270 [flang] Avoid crash from forward referenced derived type
Fortran permits forward references to derived types in contexts that don't
require knowledge of the derived type definition for semantic analysis,
such as in the declaration of a pointer or allocatable variable or component.
But when the forward-referenced derived type is used later for a component
reference, it is possible for the DerivedTypeSpec in he base variable or component
declaration to still have a null scope pointer even if the type has been defined,
since DerivedTypeSpec and TypeSpec objects are created in scopes of use
rather than in scopes of definition.  The fix is to call
DerivedTypeSpec::Instantiate() in the name resolution of each component
name so that the scope gets filled in if it is still null.

Differential Revision: https://reviews.llvm.org/D129681
2022-07-13 16:58:26 -07:00
Peter Klausler 0406c0cda6 [flang] Ensure name resolution visits "=>NULL()" in entity-decl
Most modern Fortran programs declare procedure pointers with a
procedure-declaration-stmt, but it's also possible to declare one
with a type-declaration-stmt with a POINTER attribute.  In this
case, e.g. "real, external, pointer :: p => null()" the initializer
is required to be a null-init.  The parse tree traversal in name
resolution would visit the null-init if the symbol were an object
pointer only, leading to a crash in the case of a procedure pointer.

That explanation of the bug is longer than the fix.  In short,
ensure that a null-init in an entity-decl is visited for both
species of pointers.

Differential Revision: https://reviews.llvm.org/D129676
2022-07-13 16:36:25 -07:00
Peter Klausler ae93d8ea42 [flang] Fold TRANSFER()
Fold usage of the raw data reinterpretation intrinsic function TRANSFER().

Differential Revision: https://reviews.llvm.org/D129671
2022-07-13 15:34:48 -07:00
Peter Klausler 62d874f203 [flang] Refine semantic checks for procedure pointer assignment
Some procedure pointers and EXTERNAL procedures have neither
explicit interfaces nor result types; these procedures are obviously
not known to be functions, but they could be, so semantics must not
assume that they are necessarily subroutines.  Refine the procedure
pointer / dummy procedure compatibility check to handle these more
ambiguous cases and not elicit inappropriate error messages.

Differential Revision: https://reviews.llvm.org/D129674
2022-07-13 14:56:50 -07:00
Nimish Mishra 5cbe39ef88 [flang][OpenMP] Allow default(none) to access variables with PARAMETER attribute
This patch fixes https://github.com/flang-compiler/f18-llvm-project/issues/1351.
Concretely, data-sharing attributes on PARAMETER data used in a block
with DEFAULT(NONE) should be ignored.

Reviewed By: kiranchandramohan

Differential Revision: https://reviews.llvm.org/D129444
2022-07-12 00:33:14 +05:30
Valentin Clement 36e24da8eb
[flang][openacc][NFC] Make self clause value optional in ACC.td and extract the parser
Set the isOptional flag for the self clause. Move the optional and parenthesis part of the parser. Update the rest of the code to deal with the optional value.

Preparatory work for D106968.

Reviewed By: kiranchandramohan

Differential Revision: https://reviews.llvm.org/D106965
2022-07-08 15:45:12 +02:00
Peter Klausler 6052025b58 [flang] Add IsElementalProcedure() predicate
Replace most tests of the explicit Attr::ELEMENTAL symbol flag with
a new predicate IsElementalProcedure() that works correctly for alternate
ENTRY points and does the right thing for procedure interfaces that
reference elemental intrinsic functions like SIN() whose elemental
nature does not propagate.

Differential Revision: https://reviews.llvm.org/D129022
2022-07-06 18:08:45 -07:00
Peter Klausler 23c2bedfd9 [flang] Establish a single source of target information for semantics
Create a TargetCharacteristics class to centralize the few items of
target specific information that are relevant to semantics.  Use the
new class for all target queries, including derived type component layout
modeling.

Future work will initialize this class with target information
provided or forwarded by the drivers, and use it to fold layout-dependent
intrinsic functions like TRANSFER().

Differential Revision: https://reviews.llvm.org/D129018

Updates: Attempts to work around build issues on Windows.
2022-07-06 10:25:34 -07:00
Peter Klausler f161964e1c [flang] Better error recovery for bad submodules
When a submodule appears in a source file and the compiler can't find the
named ancestor module (and submodule, if one appears), crashes may occur
later due to the absence of a scope.  For better resilience, a dummy
ancestral scope should be generated within which the submodule scope
can be created.

Differential Revision: https://reviews.llvm.org/D128760
2022-06-29 11:34:51 -07:00
Peixin-Qiao 779d2470a4 [flang] Support check for BIND statement entity
As Fortran 2018 8.6.4(1), the BIND statement specifies the BIND attribute
for a list of variables and common blocks.

Reviewed By: klausler

Differential Revision: https://reviews.llvm.org/D127120
2022-06-29 11:25:19 +08:00
Peter Klausler cfd474e0d0 [flang] Enforce C1552, no binding labels allowed for internal procedures
If BIND(C) appears on an internal procedure, it must have a null binding
label, i.e. BIND(C,NAME="").

Also address conflicts with D127725 which was merged during development.

Differential Revision: https://reviews.llvm.org/D128676
2022-06-28 11:00:12 -07:00
Peixin-Qiao 27afb362b1 [flang][OpenMP] Initial support the lowering of copyin clause
This supports the lowering of copyin clause initially. The pointer,
allocatable, common block, polymorphic varaibles will be supported
later.

This also includes the following changes:

1. Resolve the COPYIN clause and make the entity as host associated.

2. Fix collectSymbolSet by adding one option to control collecting the
   symbol itself or ultimate symbol of it so that it can be used
   explicitly differentiate the host and associated variables in
   host-association.

3. Add one helper function `lookupOneLevelUpSymbol` to differentiate the
   usage of host and associated variables explicitly. The previous
   lowering of firstprivate depends on the order of
   `createHostAssociateVarClone` and `lookupSymbol` of host symbol. With
   this fix, this dependence is removed.

4. Reuse `copyHostAssociateVar` for copying operation of COPYIN clause.

Reviewed By: kiranchandramohan, NimishMishra

Differential Revision: https://reviews.llvm.org/D127468
2022-06-24 15:33:09 +08:00
Peixin Qiao 3fa62efdbb [flang] Add semantic check for C1520
As Fortran 2018 C1520, if proc-language-binding-spec with NAME= is
specified, then proc-decl-list shall contain exactly one proc-decl,
which shall neither have the POINTER attribute nor be a dummy procedure.
Add this check.

Reviewed By: klausler

Differential Revision: https://reviews.llvm.org/D127725
2022-06-23 00:04:24 +08:00
Nimish Mishra c05b99971f [flang][OpenMP][NFC] Refactor code related to OpenMP atomic memory order clause semantics
Reviewed By: peixin

Differential Revision: https://reviews.llvm.org/D127822
2022-06-19 22:36:40 +05:30
Peter Klausler b67984d356 [flang] Handle module subprogram with interface in same (sub)module when writing module file
There's a few (3) cases where Fortran allows two distinct symbols to have
the same name in the same scope.  Module file output copes with only two of
them.  The third involves a separate module procedure that isn't separate:
both the procedure and its declared interface appear in the same (sub)module.
Fix to ensure that the interface is included in the module file output, so
that the module file reader doesn't suffer a bogus error about a "separate
module procedure without an interface".

Differential Revision: https://reviews.llvm.org/D127784
2022-06-16 10:08:41 -07:00
Peter Klausler eb6cd7fe31 [flang] ERROR STOP is not an image control statement
The predicate that determines image control statements needs
to distinguish STOP (which is) from ERROR STOP (which isn't).

Differential Revision: https://reviews.llvm.org/D127796
2022-06-15 14:39:31 -07:00
Peter Klausler bcad53e131 [flang] Add more qualification when creating names for compiler-generated USEs
When generic resolution finds its specific procedure in a module,
and that specific procedure is not use-associated into the local scope
(perhaps because it was PRIVATE, perhaps because the generic was
use-associated with ONLY:), we create a new use-association with
a renaming.  The name constructed for this renaming needs to be
additionally qualified with the module name of the specific procedure
in order to avoid clashing with another specific of the same name
that may have previously been use-associated in the same way from
a distinct module.

Differential Revision: https://reviews.llvm.org/D127790
2022-06-15 14:18:28 -07:00
PeixinQiao 60e359943b [flang] Fix one regression failure related to BIND(C) statement
For BIND(C) statement, two common block with the same name can have the
same bind name. Fix the regression failure by adding this check. Also add
the regression tests.

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

Reviewed By: clementval

Differential Revision: https://reviews.llvm.org/D127841
2022-06-15 21:10:36 +08:00
Peixin-Qiao 9441003b52 [flang][OpenMP] Add one semantic check for data-sharing clauses
As OpenMP 5.0, for firstprivate, lastprivate, copyin, and copyprivate
clauses, if the list item is a polymorphic variable with the allocatable
attribute, the behavior is unspecified.

Reviewed By: kiranchandramohan

Differential Revision: https://reviews.llvm.org/D127601
2022-06-15 16:02:27 +08:00
Peixin-Qiao 3151fb5ef7 [flang] Change C889 from error into warning
This constraint is used in OMP2012 benchmark, and other compilers do not
enforce it. Change it into one warning. This addresses the issue
https://github.com/llvm/llvm-project/issues/56003.

Reviewed By: klausler, kiranchandramohan

Differential Revision: https://reviews.llvm.org/D127740
2022-06-15 15:39:13 +08:00
Peixin-Qiao dafd3cf8b1 [flang] Complement one-to-one association check of bind name and entity name
As Fortran 2018 C802 and C873, if bind name is specified, there can only
be only one entity. The check for common block is missed before. As
Fortran 2018 8.5.5 point 2, the bind name is one identifier, which is
unique. That is, one entity can not have multiple bind names. Also add
this check.

Reviewed By: klausler, Jean Perier

Differential Revision: https://reviews.llvm.org/D126961
2022-06-14 10:34:38 +08:00
Peixin-Qiao c6d8aa27c5 [flang] Add semantic check for multiple part-ref with nonzero rank for TBP
As Fortran 2018 C919, there shall not be more than one part-ref with
nonzero rank. Support this semantic check for type-bound procedure to
address the issue https://github.com/llvm/llvm-project/issues/55811.

Reviewed By: klausler

Differential Revision: https://reviews.llvm.org/D127602
2022-06-14 10:17:44 +08:00
Peter Klausler f472c099be [flang] Handle USE association in parse tree rewriting
f18 was treating "f() = 1" as a statement function definition
if it could be viewed as being in the specification part and
"f" was a USE-associated function returning a data pointer.
(The non-USE-associated case is fine.)  Fix to allow for "f"
to be USE associated.

Differential Revision: https://reviews.llvm.org/D127430
2022-06-13 16:20:51 -07:00
Peter Klausler 8eebf46964 [flang] Fix crash on USE error
Handle the case of a non-generic procedure that is USE associated
into a scope that has a generic interface of the same name with an
appropriate error rather than crashing.

Differential Revision: https://reviews.llvm.org/D127429
2022-06-13 16:15:47 -07:00
Peter Klausler ee9c917048 [flang] Fix bogus branch target error on END SELECT
The scope model used for branch target checking treats a label
on an END SELECT statement as if it were in the previous CASE block.
This makes it illegal to GO TO that label from within any earlier
CASE block in that statement.  Fix by treating the CASE blocks as
nested scopes within the scope of the SELECT construct.

Also, add a "warning:" tag to related warning messages.

Differential Revision: https://reviews.llvm.org/D127425
2022-06-13 11:42:55 -07:00
PeixinQiao 1f17a8978c [flang] Add one missed semantic check for named constant in common block
As Fortran 2018 R874, common block object must be one variable name, which
cannot be one named constant. Add this check.

Reviewed By: klausler

Differential Revision: https://reviews.llvm.org/D126762
2022-06-09 00:43:30 +08:00