Commit Graph

19 Commits

Author SHA1 Message Date
Peter Klausler cd03e96f00 [flang] Add & use a better visit() (take 2)
Adds flang/include/flang/Common/log2-visit.h, which defines
a Fortran::common::visit() template function that is a drop-in
replacement for std::visit().  Modifies most use sites in
the front-end and runtime to use common::visit().

The C++ standard mandates that std::visit() have O(1) execution
time, which forces implementations to build dispatch tables.
This new common::visit() is O(log2 N) in the number of alternatives
in a variant<>, but that N tends to be small and so this change
produces a fairly significant improvement in compiler build
memory requirements, a 5-10% improvement in compiler build time,
and a small improvement in compiler execution time.

Building with -DFLANG_USE_STD_VISIT causes common::visit()
to be an alias for std::visit().

Calls to common::visit() with multiple variant arguments
are referred to std::visit(), pending further work.

This change is enabled only for GCC builds with GCC >= 9;
an earlier attempt (D122441) ran into bugs in some versions of
clang and was reverted rather than simply disabled; and it is
not well tested with MSVC. In non-GCC and older GCC builds,
common::visit() is simply an alias for std::visit().
2022-04-16 16:00:48 -07:00
Andrzej Warzynski 4ca111d4cb Revert "[flang] Add & use a better visit()"
This reverts commit 2ab9990c9e. It has
caused multiple build failures:
*  https://lab.llvm.org/buildbot/#/builders/177/builds/4346
*  https://lab.llvm.org/buildbot/#/builders/180/builds/3803
*  https://lab.llvm.org/buildbot/#/builders/175/builds/10419
*  https://lab.llvm.org/buildbot/#/builders/191/builds/4318
*  https://lab.llvm.org/buildbot/#/builders/173/builds/4274
*  https://lab.llvm.org/buildbot/#/builders/181/builds/4297

All these bots failed with a time-out:
```
command timed out: 1200 seconds without output running [b'ninja', b'-j', b'32'], attempting to kill
```
I'm guessing that that's due to template instantiations failing at some
point (https://reviews.llvm.org/D122441 introduced a custom
implementation of std::visit). Everything seems fine when either:
* building on X86 with GCC or Clang (tested with GCC 9.3 and Clang 12)
* building on AArch64 with GCC (tested with GCC 11)
2022-03-28 10:46:47 +00:00
Peter Klausler 2ab9990c9e [flang] Add & use a better visit()
Adds flang/include/flang/Common/visit.h, which defines
a Fortran::common::visit() template function that is a drop-in
replacement for std::visit().  Modifies most use sites in
the front-end and runtime to use common::visit().

The C++ standard mandates that std::visit() have O(1) execution
time, which forces implementations to build dispatch tables.
This new common::visit() is O(log2 N) in the number of alternatives
in a variant<>, but that N tends to be small and so this change
produces a fairly significant improvement in compiler build
memory requirements, a 5-10% improvement in compiler build time,
and a small improvement in compiler execution time.

Building with -DFLANG_USE_STD_VISIT causes common::visit()
to be an alias for std::visit().

Calls to common::visit() with multiple variant arguments
are referred to std::visit(), pending further work.

Differential Revision: https://reviews.llvm.org/D122441
2022-03-25 13:15:20 -07:00
Peter Klausler a53967cd55 [flang] Distinguish usage and portability warning messages
Using recently established message severity codes, upgrade
non-fatal messages to usage and portability warnings as
appropriate.

Differential Revision: https://reviews.llvm.org/D121246
2022-03-08 17:24:52 -08:00
Peter Klausler c4f67ea12e [flang] Allow DATA initialization of derived types w/ allocatable components
While one cannot of course statically initialize an allocatable component
of an instance of a derived type, its mere presence should not prevent
DATA initialization of the other nonallocatable components.  Semantics
was treating the existence of an allocatable component as a case of
"default initialization", which it is, but not one that should run
afoul of C877.  Add another Boolean argument to IsInitialized() to allow
for a more nuanced test.

Differential Revision: https://reviews.llvm.org/D119449
2022-02-14 10:43:49 -08:00
Peter Klausler 63a2987d51 [flang] Allow initialization in blank COMMON
This is nonconformant usage, but widely accepted as an extension.
Downgrade the error message to a warning.

Differential Revision: https://reviews.llvm.org/D117152
2022-01-13 15:07:37 -08:00
Peter Klausler c14cf92b5a [flang] Implement semantics for DEC STRUCTURE/RECORD
Implements part of the legacy "DEC structures" feature from
VMS Fortran.  STRUCTUREs are processed as if they were derived
types with SEQUENCE.  DATA-like object entity initialization
is supported as well (e.g., INTEGER FOO/666/) since it was used
for default component initialization in structures.  Anonymous
components (named %FILL) are also supported.

These features, and UNION/MAP, were already being parsed.
An omission in the collection of structure field names in the
case of nested structures with entity declarations was fixed
in the parser.

Structures are supported in modules, but this is mostly for
testing purposes.  The names of fields in structures accessed
via USE association cannot appear with dot notation in client
code (at least not yet).  DEC structures antedate Fortran 90,
so their actual use in applications should not involve modules.

This patch does not implement UNION/MAP, since that feature
would impose difficulties later in lowering them to MLIR types.
In the meantime, if they appear, semantics will issue a
"not yet implemented" error message.

Differential Revision: https://reviews.llvm.org/D117151
2022-01-13 13:17:13 -08:00
peter klausler 57705df2de [flang] Catch error: base of DATA statement object can't be a pointer
A pointer with subscripts, substring indices, or components cannot
be initialized by a DATA statement (although of course a whole pointer
can be so).  Catch the missing cases.

Differential Revision: https://reviews.llvm.org/D109931
2021-09-22 14:41:48 -07:00
peter klausler 7f8da0791c [flang] Refine checks for pointer initialization targets
f18 was emitting a bogus error message about the lack of a TARGET
attribute when a pointer was initialized with a component of a
variable that was a legitimate TARGET.

Differential Revision: https://reviews.llvm.org/D99665
2021-03-31 11:32:12 -07:00
peter klausler 4ac617f490 [flang] Handle DATA initialization of EQUIVALENCE'd objects
Objects that are storage associated by EQUIVALENCE and
initialized with DATA are initialized by creating a
compiler temporary data object in the same scope,
assigning it an offset, type, and size that covers the
transitive closure of the associated initialized original
symbols, and combining their initializers into one common
initializer for the temporary.

Some problems with offset assignment of EQUIVALENCE'd objects
in COMMON were exposed and corrected, and some more error
cases are checked.

Remove obsolete function.
Small bugfix (nested implied dos).
Add a test.
Fix struct/class warning.

Differential Revision: https://reviews.llvm.org/D85560
2020-08-07 16:39:23 -07:00
peter klausler 43b304b09f [flang] Support DATA statement initialization of numeric with Hollerith/CHARACTER
This is a common Fortran language extension.

Differential Revision: https://reviews.llvm.org/D85492
2020-08-07 13:17:36 -07:00
Tim Keith dd90408262 [flang][NFC] Get formatting in sync with latest clang-format
flang/module only contains Fortran files and one is a .h so disable
formatting on that directory.

Differential Revision: https://reviews.llvm.org/D82989
2020-07-01 16:51:46 -07:00
peter klausler a20d48d7d3 [flang] DATA stmt processing (part 4/4): Check & convert DATA
Implement rest of DATA statement semantics and conversion of
DATA statement initializations into static initializers of
objects in their symbol table entries.

Reviewed By: tskeith, PeteSteinfeld

Differential Revision: https://reviews.llvm.org/D82207
2020-06-19 13:26:20 -07:00
peter klausler 4171f80d54 [flang] DATA stmt processing (part 3/4): Remaining prep work
Rolls up small changes across the frontend to prepare for the large
forthcoming patch (part 4/4) that completes DATA statement processing
via conversion to initializers.

Reviewed By: PeteSteinfeld

Differential Revision: https://reviews.llvm.org/D82137
2020-06-19 09:09:05 -07:00
Anchu Rajendran 70f1b4b412 [flang] Implemented 2 Semantic checks for DATA statement and fixed a few bugs
Summary
  - Implemented C876, C877
  - Fixed IsConstantExpr to check C879
  - Fixed bugs in few test cases - data01.f90, block-data01.f90,
  pre-fir-tree02.f90
  - Modified implementation of C8106 to identify all automatic objects
  and modified equivalence01.f90 to reflect the changes

Differential Revision: https://reviews.llvm.org/D78424
2020-06-03 10:33:26 +05:30
peter klausler 3a1afd8c3d Rework DATA statement semantics to use typed expressions
Summary:
Updates recent work on DATA statement semantic checking in
flang/lib/Semantics/check-data.{h,cpp} to use the compiler's
internal representation for typed expressions rather than working
on the raw parse tree.  Saves the analyzed expressions for DATA
statement values as parse tree decorations because they'll soon be
needed in lowering.  Corrects wording of some error messages.

Fixes a bug in constant expression checking: structure constructors
are not constant expressions if they set an allocatable component
to anything other than NULL.

Includes infrastructure changes to make this work, some renaming
to reflect the fact that the implied DO loop indices tracked by
expression analysis are not (just) from array constructors, remove
some dead code, and improve some comments.

Reviewers: tskeith, sscalpone, jdoerfert, DavidTruby, anchu-rajendran, schweitz

Reviewed By: tskeith, anchu-rajendran, schweitz

Subscribers: llvm-commits, flang-commits

Tags: #flang, #llvm

Differential Revision: https://reviews.llvm.org/D78834
2020-04-25 10:29:34 -07:00
Anchu Rajendran c1c01212c4 [flang]Implemented Semantic Checkes for 5 data constraints
Summary:
 C874, C875, C878, C880 and C881 checks are implemented.

Differential Revision: https://reviews.llvm.org/D78008
2020-04-18 12:21:30 +05:30
Tim Keith 1f8790050b [flang] Reformat with latest clang-format and .clang-format
Original-commit: flang-compiler/f18@9fe84f45d7
Reviewed-on: https://github.com/flang-compiler/f18/pull/1094
2020-03-28 21:00:16 -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