Commit Graph

9 Commits

Author SHA1 Message Date
peter klausler a50bb84ec0 [flang] Fix classification of shape inquiries in specification exprs
In some contexts, including the motivating case of determining whether
the expressions that define the shape of a variable are "constant expressions"
in the sense of the Fortran standard, expression rewriting via Fold()
is not necessary, and should not be required.  The inquiry intrinsics LBOUND,
UBOUND, and SIZE work correctly now in specification expressions and are
classified correctly as being constant expressions (or not).  Getting this right
led to a fair amount of API clean-up as a consequence, including the
folding of shapes and TypeAndShape objects, and new APIs for shapes
that do not fold for those cases where folding isn't needed.  Further,
the symbol-testing predicate APIs in Evaluate/tools.h now all resolve any
associations of their symbols and work transparently on use-, host-, and
construct-association symbols; the tools used to resolve those associations have
been defined and documented more precisely, and their clients adjusted as needed.

Differential Revision: https://reviews.llvm.org/D94561
2021-01-13 10:05:14 -08:00
peter klausler 641ede93ef [flang] Improve initializer semantics, esp. for component default values
This patch plugs many holes in static initializer semantics, improves error
messages for default initial values and other component properties in
parameterized derived type instantiations, and cleans up several small
issues noticed during development.  We now do proper scalar expansion,
folding, and type, rank, and shape conformance checking for component
default initializers in derived types and PDT instantiations.
The initial values of named constants are now guaranteed to have been folded
when installed in the symbol table, and are no longer folded or
scalar-expanded at each use in expression folding.  Semantics documentation
was extended with information about the various kinds of initializations
in Fortran and when each of them are processed in the compiler.

Some necessary concomitant changes have bulked this patch out a bit:
* contextual messages attachments, which are now produced for parameterized
  derived type instantiations so that the user can figure out which
  instance caused a problem with a component, have been added as part
  of ContextualMessages, and their implementation was debugged
* several APIs in evaluate::characteristics was changed so that a FoldingContext
  is passed as an argument rather than just its intrinsic procedure table;
  this affected client call sites in many files
* new tools in Evaluate/check-expression.cpp to determine when an Expr
  actually is a single constant value and to validate a non-pointer
  variable initializer or object component default value
* shape conformance checking has additional arguments that control
  whether scalar expansion is allowed
* several now-unused functions and data members noticed and removed
* several crashes and bogus errors exposed by testing this new code
  were fixed
* a -fdebug-stack-trace option to enable LLVM's stack tracing on
  a crash, which might be useful in the future

TL;DR: Initialization processing does more and takes place at the right
times for all of the various kinds of things that can be initialized.

Differential Review: https://reviews.llvm.org/D92783
2020-12-07 14:40:41 -08:00
sameeran joshi 4a51691a85 [Flang][OpenACC] Fix for branching out issue in OpenACC parallel construct.
From OpenACC 3.0 Standards document
	840 • A program may not branch into or out of an OpenACC parallel construct.
	Exits are allowed provided it does not cause an exit outside the parallel region.

	Test case exits out of the inner do loop, but it is still inside the parallel region.
	Patch tries to extract labels from block attached to a construct,
	If the exit is to a label not in the collected list then flags an error.

Reviewed By: tskeith

Differential Revision: https://reviews.llvm.org/D87906
2020-10-19 21:46:47 +05:30
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
Pete Steinfeld 4d8c00c059 [flang] Fix crash on erroneous expressions
Summary:
If you create an expression with parse errors, the `parser::Expr.typedExpr`
will be empty, which causes a compiler crash.  The crash is caused by the
check in check-do-forall.cpp that scans all expresssions to see if `DO`
variables are being modified.

It turned out that the problem was that I was fetching subexpressions of type
`parser::Expr`, which are not guaranteed to have a non-null `typedExpr`.  I
fixed this by only grabbing the top-level expression from which to gather
arguments as part of the DO loop analysis.  This, in turn, exposed a problem
where I wasn't collecting all of the actual arguments in an expression.  This
was caused by the fact that I wasn't recursing through the rest of the
expression after finding an argument.  I fixed this by recursing through the
argument in the member function in `CollectActualArgumentsHelper`.

Reviewers: klausler, tskeith, DavidTruby

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D81101
2020-06-05 08:46:43 -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
David Truby cc77f818f2 [flang] Add explicit nullptr check in initialisation of inDoConstruct.
This explicit check is needed as we are using braced initialisation here so
implicit narrowing conversions (such as pointer to bool) are not allowed.

Original-commit: flang-compiler/f18@ff8dad10bf
Reviewed-on: https://github.com/flang-compiler/f18/pull/1083
2020-03-25 18:37:31 +00:00
Tim Keith c875618506 [flang] Remove use of std::set::merge
Some versions of clang that we are building with don't have
std::set::merge, even though it is part of C++17. Work around
that by using std::set::insert until we can count on merge being
available everywhere.

Original-commit: flang-compiler/f18@886ccc37fb
Reviewed-on: https://github.com/flang-compiler/f18/pull/1014
2020-02-26 16:10:11 -08:00
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