21 Commits

Author SHA1 Message Date
peter klausler
b82a8c3f23 [flang] Warn about useless explicit typing of intrinsics
Fortran 2018 explicitly permits an ignored type declaration
for the result of a generic intrinsic function.  See the comment
added to Semantics/expression.cpp for an explanation of why this
is somewhat dangerous and worthy of a warning.

Differential Revision: https://reviews.llvm.org/D96879
2021-02-17 13:13:59 -08:00
Peter Steinfeld
77dc203cd0 [flang] Detect circularly defined procedures
It's possible to define a procedure that has a procedure dummy argument which
names the procedure that contains it.  This was causing the compiler to fall
into an infinite loop when characterizing a call to the procedure.

Following a suggestion from Peter, I fixed this be maintaining a set of
procedure symbols that had already been seen while characterizing a procedure.
This required passing a new parameter to the functions that characterized a
Procedure, a DummyArgument, and a DummyProcedure.

I also added several tests that will crash the compiler without this change.

Differential Revision: https://reviews.llvm.org/D96631
2021-02-16 14:40:35 -08:00
peter klausler
efc5926c20 [flang] Add TypeAndShape::MeasureElementSizeInBytes()
Split up MeasureSizeInBytes() so that array element sizes can be
calculated accurately; use the new API in some places where
DynamicType::MeasureSizeInBytes() was being used but the new
API performs better due to TypeAndShape having precise CHARACTER
length information.

Differential Revision: https://reviews.llvm.org/D95897
2021-02-02 15:15:20 -08:00
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 klausler
0996b590aa [flang] Infrastructure improvements in utility routines
* IsArrayElement() needs another option to control whether it
  should ignore trailing component references.
* Add IsObjectPointer().
* Add const Scope& variants of IsFunction() and IsProcedure().
* Make TypeAndShape::Characterize() work with procedure bindings.
* Handle CHARACTER length in MeasureSizeInBytes().
* Fine-tune FindExternallyVisibleObject()'s handling of dummy arguments
  to conform with Fortran 2018: only INTENT(IN) and dummy pointers
  in pure functions signify; update two tests accordingly.

Also: resolve some stylistic inconsistencies and add a missing
"const" in the expression traversal template framework.

Differential Revision: https://reviews.llvm.org/D95011
2021-01-20 12:40:25 -08:00
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
6aa3591e98 [flang] Implement STORAGE_SIZE(), SIZEOF(), C_SIZEOF()
STORAGE_SIZE() is a standard inquiry intrinsic (size in bits
of an array element of the same type as the argument); SIZEOF()
is a common extension that returns the size in bytes of its
argument; C_SIZEOF() is a renaming of SIZEOF() in module ISO_C_BINDING.

STORAGE_SIZE() and SIZEOF() are implemented via rewrites to
expressions; these expressions will be constant when the necessary
type parameters and bounds are also constant.

Code to calculate the sizes of types (with and without alignment)
was isolated into Evaluate/type.* and /characteristics.*.
Code in Semantics/compute-offsets.* to calculate sizes and alignments
of derived types' scopes was exposed so that it can be called at type
instantiation time (earlier than before) so that these inquiry intrinsics
could be called from specification expressions.

Differential Revision: https://reviews.llvm.org/D93322
2020-12-15 17:26:20 -08:00
peter klausler
d6a74ec826 [flang] Fix false error message for "ptr => func()" array conformance
Pointers must have deferred shapes, so CheckConformance must be
extended to allow for them.

Differential Revision: https://reviews.llvm.org/D93320
2020-12-15 16:26:18 -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
peter klausler
934b27a9da [flang] Fix actual argument character length and length error reporting
Ensure that character length is properly calculated for
actual arguments to intrinsics, and that source provenance
information is available when expression analysis calls
folding in cases where the length is invalid.

Differential revision: https://reviews.llvm.org/D90636
2020-11-02 13:39:15 -08:00
Jean Perier
29d1a49447 [flang] Document and use intrinsic subroutine argument intents
Check INTENT(OUT)/INTENT(INOUT) constraints for actual argument
of intrinsic procedure calls.
- Adding a common::Intent field to the IntrinsicDummyArgument
in the intrinsic table.
- Propagating it to the DummyDataObject intent field so that it can
later be used in CheckExplicitDataArg semantic checks.
- Add related tests.
- Fix regression (C846 false error), C846 INTENT(OUT) rule does
  not apply to intrinsic call. Propagate the information that we
  are in an intrinsic call up to CheckExplicitDataArg (that is
  doing this check). Still enforce C846 on intrinsics other than MOVE_ALLOC (for which
  allocatable coarrays are explicitly allowed) since it's not clear it is allowed in all
  intrinsics and allowing this would lead to runtime penalties in the intrinsic runtime.

Differential Revision: https://reviews.llvm.org/D89473
2020-10-20 14:09:46 +02:00
Peter Steinfeld
c757418869 [flang] Failed call to CHECK() for call to ASSOCIATED(NULL())
Calling "ASSOCATED(NULL()) was causing an internal check of the compiler to
fail.

I fixed this by changing the entry for "ASSOCIATED" in the intrinsics table to
accept "AnyPointer" which contains a new "KindCode" of "pointerType".  I also
changed the function "FromActual()" to return a typeless intrinsic when called
on a pointer, which duplicates its behavior for BOZ literals.  This required
changing the analysis of procedure arguments.  While testing processing for
procedure arguments, I found another bad call to `CHECK()` which I fixed.

I made several other changes:
  -- I implemented constant folding for ASSOCIATED().
  -- I fixed handling of NULL() in relational operations.
  -- I implemented semantic analysis for ASSOCIATED().
    -- I noticed that the semantics for ASSOCIATED() are similar to those for
       pointer assignment.  So I extracted the code that pointer assignment uses
       for procedure pointer compatibility to a place where it could be used by
       the semantic analysis for ASSOCIATED().
    -- I couldn't figure out how to make the general semantic analysis for
       procedure arguments work with ASSOCIATED()'s second argument, which can
       be either a pointer or a target.  So I stopped using normal semantic
       analysis for arguments for ASSOCIATED().
  -- I added tests for all of this.

Differential Revision: https://reviews.llvm.org/D88313
2020-10-16 07:12:57 -07:00
peter klausler
53bf28b80c [flang] Track CHARACTER length better in TypeAndShape
CHARACTER length expressions were not always being
captured or computed as part of procedure "characteristics",
leading to test failures due to an inability to compute
memory size expressions accurately.

Differential revision: https://reviews.llvm.org/D88689
2020-10-06 08:45:46 -07:00
peter klausler
37b2e2b04c [flang] Semantic analysis for FINAL subroutines
Represent FINAL subroutines in the symbol table entries of
derived types.  Enforce constraints.  Update tests that have
inadvertent violations or modified messages.  Added a test.

The specific procedure distinguishability checking code for generics
was used to enforce distinguishability of FINAL procedures.
(Also cleaned up some confusion and redundancy noticed in the
type compatibility infrastructure while digging into that area.)

Differential revision: https://reviews.llvm.org/D88613
2020-09-30 15:46:15 -07:00
Jean Perier
bd72ed93d2 [flang] CHARACTER(*) return does not require explicit interface
Fortran 2018 15.4.2.2(4)(c) says nonassumed or explicit non-constant
length parameter require explicit interface. The "nonassumed" part was
missing in f18 characteristic analysis causing CanBeCalledViaImplicitInterface
to return false for `CHARACTER(*) function foo()` like interfaces.

Reviewed By: klausler

Differential Revision: https://reviews.llvm.org/D88075
2020-09-23 13:38:10 +02:00
peter klausler
fad31d6032 [flang] Implement shape analysis of TRANSFER intrinsic function result
The shape (esp. the size) of the result of a call to TRANSFER
is implemented according to the definition in the standard.

Differential Revision: https://reviews.llvm.org/D85866
2020-08-13 09:56:24 -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
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
Tim Keith
61b1390e2a [flang] Check module subprogram against separate module procedure
When a module subprogram has the MODULE prefix the following must match
with the corresponding separate module procedure interface body:
- C1549: characteristics and dummy argument names
- C1550: binding label
- C1551: NON_RECURSIVE prefix

SubprogramMatchHelper performs all of these checks.

Rename separate-module-procs.f90 to separate-mp01.f90 so we can have
separate-mp02.f90 (etc).

Make ShapesAreCompatible public in characteristics.h.

Add Scope::IsSubmodule.

Original-commit: flang-compiler/f18@d121578af1
Reviewed-on: https://github.com/flang-compiler/f18/pull/1080
2020-03-17 16:01:59 -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