Commit Graph

25 Commits

Author SHA1 Message Date
Peter Klausler cebf1348df [flang] Correct epistemological edge cases for IS_CONTIGUOUS folding
Don't return a hard .FALSE. when folding IS_CONTIGUOUS() unless the
subscript triplets are discontiguous and array section is nonempty,
or if the array section is nonempty and there is a vector subscript.

Differential Revision: https://reviews.llvm.org/D135334
2022-10-06 15:22:30 -07:00
Peter Klausler 9489699438 [flang] Fold IS_CONTIGUOUS() to .FALSE. when it is known to be
At present, IS_CONTIGUOUS() can only either fold to .TRUE. or
remain unknown.  The underlying analysis, however, is capable
of returning a tri-state result (true, false, or unknown).
Extend and expose it to folding so that IS_CONTIGUOUS() can
fold to .FALSE. as well as to .TRUE. when contiguity is
known.

Differential Revision: https://reviews.llvm.org/D134466
2022-09-23 14:16:26 -07:00
Peter Klausler b70f507c75 [flang] Fix folding of LEN(f(...))
LEN(f(...)), where "f" is a non-intrinsic function, should not be folded
to anything else unless the result is a known constant value.  While there
are conceivable cases in which we could do better (e.g., an internal function
whose length is a host-associated INTENT(IN) dummy argument), there are
other cases that we're getting wrong.

Differential Revision: https://reviews.llvm.org/D128759
2022-06-29 10:25:07 -07:00
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 5c5bde1bb6 [flang] Fold SCALE()
Fold references to the intrinsic function SCALE().

(Also work around some MSVC headaches somehow exposed by
this patch: disable a bogus MSVC warning that began to appear
in unrelated source files, and avoid the otherwise-necessary
use of the "template" keyword in a call to a template member
function of a class template.)

Differential Revision: https://reviews.llvm.org/D117150
2022-01-15 09:31:00 -08:00
Peter Klausler bd859cb4de [flasg] Debug folding of substring references
Character substrings weren't being folded correctly;
add tests and rework the implementation so that substrings
of literals and named constant character scalars & arrays
are properly folded for use in constant expressions.

Differential Revision: https://reviews.llvm.org/D117343
2022-01-14 16:09:06 -08:00
Peter Klausler 78d60094c7 [flang] Deal with negative character lengths in semantics
Fortran defines LEN(X) = 0 after CHARACTER(LEN=-1)::X so
apply MAX(0, ...) to character length expressions.

Differential Revision: https://reviews.llvm.org/D114030
2021-11-17 09:49:15 -08:00
peter klausler 9245f35580 [flang] Validate SIZE(x,DIM=n) dimension for assumed-size array x
Catch invalid attempts to extract the unknowable extent of the last
dimension of an assumed-size array dummy argument, and clean up
problems with assumed-rank arguments in similar circumstances
exposed by testing the fix.

Differential Revision: https://reviews.llvm.org/D109918
2021-09-17 10:14:18 -07:00
Jean Perier 1a4af2e45e [flang] preserve symbol in DescriptorInquiry
Do not use ultimate symbols in DescriptorInquiry. Using the ultimate
symbol may lead to issues later for at least two reasons:

- The original symbols may have volatile/asynchronous attributes that
  the ultimate may not have. Later phases working on the DescriptorInquiry
  would then not apply potential care required by these attributes.
- HostAssociatedDetails symbols are used by OpenMP for symbols with
  special OpenMP attributes inside OpenMP region (e.g variables with
  private attribute), so it is very important to preserve this
  aspect in the DescriptorInquiry, that would otherwise apply on the
  symbol outside of the region.

Differential Revision: https://reviews.llvm.org/D104385
2021-06-17 12:42:08 +02:00
peter klausler ac9641753b [flang] Support known constant lengths in DynamicType
The constexpr-capable class evaluate::DynamicType represented
CHARACTER length only with a nullable pointer into the declared
parameters of types in the symbol table, which works fine for
anything with a declaration but turns out to not suffice to
describe the results of the ACHAR() and CHAR() intrinsic
functions.  So extend DynamicType to also accommodate known
constant CHARACTER lengths, too; use them for ACHAR & CHAR;
clean up several use sites and fix regressions found in test.

Differential Revision: https://reviews.llvm.org/D103571
2021-06-03 14:25:22 -07:00
peter klausler 6f3d322f25 [flang] Improve shape & length characterization
Analyze the shape of the result of TRANSFER(ptr,array) correctly
when "ptr" is an array of deferred shape.  Fixing this bug led to
some refactoring and concentration of common code in TypeAndShape
member functions with code in general shape and character length
analysis, and this led to some regression test failures that have
all been cleaned up.

Differential Revision: https://reviews.llvm.org/D95744
2021-01-30 16:14:27 -08:00
Peter Steinfeld dd3eb3f332 [flang] Substrings with lower bound greater than upper bound
According to section 9.4.1, paragraph 3,
 If the starting point is greater than the ending point, the substring has
 length zero

But the compilers code for substring processing was failing a call to `CHECK()`
in this case.  I fixed this by just setting the number of items in the
resulting string to 0 for this situation.

Differential Revision: https://reviews.llvm.org/D87799
2020-09-16 14:56:23 -07:00
peter klausler 4cbfd93a59 [flang] Make `TypeParamInquiry` monomorphic
Change the expression representation TypeParamInquiry from being
a class that's templatized on the integer KIND of its result into
a monomorphic representation that results in a SubscriptInteger
that can then be converted.

This is a minor simplification, but it's worth doing because
it is believed to also be a work-around for bugs in the MSVC
compiler with overload resolution that affect the expression
traversal framework.

Differential Revision: https://reviews.llvm.org/D86551
2020-08-31 15:40:40 -07:00
Peter Steinfeld 19d7cc2e83 [flang] Fix assert on character literal substrings as arguments
Character literal substrings used as arguments were causing asserts.  This
happened when the code was trying to get the DynamicType of the substring.  We
were only recording the DynamicType of the Designator on which the substring
was based.  For character literal substrings, the Designator was a character
literal, and we weren't handling getting its type.

I fixed this by changing the `GetType()` method for `DynamicType` to check to
see if we were getting the type of a `Substring` and calculating the type of
the substring by getting the number of bytes in an element of the string.

I also changed the test `resolve49.f90` with some tests, one of which causes
the original crash.

Differential Revision: https://reviews.llvm.org/D85908
2020-08-13 09:09:05 -07:00
peter klausler 8f0f9eaddf [flang] Fix CHARACTER length folding problem
Do not rewrite LEN(x) or x%len to the expression that specifies
the length of x when that length is not a constant expression.
Its value may have changed since the value of the expression was
first captured in the definition of the object.

Reviewed By: tskeith, sscalpone

Differential Revision: https://reviews.llvm.org/D83352
2020-07-07 16:38:36 -07:00
Pete Steinfeld 1746c8ed26 [flang] Fixed crash on forward referenced `len` parameter
Summary:
Using a forward reference to define a `len` parameter causes a crash.
The underlying cause was that a previously declared type had an
erroneous expression for its `LEN` param value.  When this expression
was referenced to evaluate a subsequent expression, bad things happened.
I fixed this by putting in code to detect this case.

Reviewers: tskeith, klausler, DavidTruby

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D80593
2020-06-04 13:12:11 -07:00
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
Tim Keith 76d71354db [flang] Add message formatting for std::int64_t
There is no printf formatting string for std::int64_t. Instead we have
to cast to std::intmax_t and use `%jd`. This change simplifies that by
automatically converting std::int64_t to std::intmax_t when formatting
messages.

Original-commit: flang-compiler/f18@8a2343dfff
Reviewed-on: https://github.com/flang-compiler/f18/pull/1101
Tree-same-pre-rewrite: false
2020-04-03 17:28:23 -07:00
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
Caroline Concatto 8670e49901 [flang] [LLVMify F18] Replace the use std::ostream with LLVM streams llvm::ostream
This patch replaces the occurrence of std::ostream by llvm::raw_ostream.
In  LLVM Coding Standards[1] "All new code should use raw_ostream
instead of ostream".[1]

As a consequence, this patch also replaces the use of:
   std::stringstream by llvm::raw_string_ostream or llvm::raw_ostream*
   std::ofstream by llvm::raw_fd_ostream
   std::endl by '\n' and flush()[2]
   std::cout by llvm::outs()   and
   std::cerr by llvm::errs()

It also replaces  std::strerro by llvm::sys::StrError** , but NOT in  Fortran
runtime libraries

*std::stringstream were replaced by llvm::raw_ostream in all methods that
used std::stringstream as a parameter. Moreover, it removes the pointers to
these streams.

[1]https://llvm.org/docs/CodingStandards.html
[2]https://releases.llvm.org/2.5/docs/CodingStandards.html#ll_avoidendl

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

Running clang-format-7

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

Removing residue of ostream library

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

Original-commit: flang-compiler/f18@a3507d44b8
Reviewed-on: https://github.com/flang-compiler/f18/pull/1047
2020-03-19 07:54:36 +00:00
peter klausler e03b20e66e [flang] Changes to get a clean build of f18 with latest clang
Prep for review

Original-commit: flang-compiler/f18@111f49061e
Reviewed-on: https://github.com/flang-compiler/f18/pull/1059
2020-03-10 13:12:52 -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