Commit Graph

34 Commits

Author SHA1 Message Date
peter klausler d9195d6603 [flang] More precise checks for NULL() operands
Improve checking for NULL() and NULL(MOLD=) when used as
variables and expressions outside the few contexts where
a disassociated pointer can be valid.  There were both
inappropriate errors and missing checks.

Differential Revision: https://reviews.llvm.org/D109905
2021-09-16 15:52:45 -07:00
Mehdi Amini 0dc461441e Revert "[flang] Make 'this_image()' an intrinsic function"
This reverts commit 81f8ad1769.
This seems to break the shared libs build
(linaro-flang-aarch64-sharedlibs bot) with:

  undefined reference to `Fortran::semantics::IsCoarray(Fortran::semantics::Symbol const&)

(from tools/flang/lib/Evaluate/CMakeFiles/obj.FortranEvaluate.dir/tools.cpp.o)

When linking lib/libFortranEvaluate.so.14git
2021-09-15 03:28:34 +00:00
Craig Rasmussen 81f8ad1769 [flang] Make 'this_image()' an intrinsic function
Added 'this_image()' to the list of functions that are evaluated as intrinsic.
Added IsCoarray functions to determine if an expression is a coarray (corank > 1).

Added save attribute to coarray variables in test file, this_image.f90.

reviewers: klausler, PeteSteinfeld

Differential Revision: https://reviews.llvm.org/D108059
2021-09-14 16:40:08 -07:00
peter klausler c4a65434d8 [flang] Symbol representation for dummy SubprogramDetails
Dummy procedures can be defined as subprograms with explicit
interfaces, e.g.

  subroutine subr(dummy)
    interface
      subroutine dummy(x)
        real :: x
      end subroutine
    end interface
    ! ...
  end subroutine

but the symbol table had no means of marking such symbols as dummy
arguments, so predicates like IsDummy(dummy) would fail.  Add an
isDummy_ flag to SubprogramNameDetails, analogous to the corresponding
flag in EntityDetails, and set/test it as needed.

Differential Revision: https://reviews.llvm.org/D106697
2021-08-02 10:44:27 -07:00
peter klausler a48e41683a [flang] Run-time derived type initialization and destruction
Use derived type information tables to drive default component
initialization (when needed), component destruction, and calls to
final subroutines.  Perform these operations automatically for
ALLOCATE()/DEALLOCATE() APIs for allocatables, automatics, and
pointers.  Add APIs for use in lowering to perform these operations
for non-allocatable/automatic non-pointer variables.
Data pointer component initialization supports arbitrary constant
designators, a F'2008 feature, which may be a first for Fortran
implementations.

Differential Revision: https://reviews.llvm.org/D106297
2021-07-20 15:24:16 -07:00
peter klausler 47f18af55f [flang] Fold MAXVAL & MINVAL
Implement constant folding for the reduction transformational
intrinsic functions MAXVAL and MINVAL.

In anticipation of more folding work to follow, with (I hope)
some common infrastructure, these two have been implemented in a
new header file.

Differential Revision: https://reviews.llvm.org/D104337
2021-06-16 14:06:34 -07:00
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 6829bd3ed0 [flang] (NFC) Expose internal idiom as utility API
Add overloads to AsGenericExpr() in Evaluate/tools.h to take care
of wrapping an untyped DataRef or bare Symbol in a typed Designator
wrapped up in a generic Expr<SomeType>.  Use the new overloads to
replace a few instances of code that was calling TypedWrapper<>()
with a dynamic type.

This new tool will be useful in lowering to drive some code that
works with typed expressions (viz., list-directed I/O list items)
when starting with only a bare Symbol (viz., NAMELIST).

Differential Revision: https://reviews.llvm.org/D102352
2021-05-13 11:19:37 -07:00
Peter Steinfeld e9be1e7d84 [flang] Fix checking of argument passing for parameterized derived types
We were erroneously not taking into account the constant values of LEN type
parameters of parameterized derived types when checking for argument
compatibility.  The required checks are identical to those for assignment
compatibility.  Since argument compatibility is checked in .../lib/Evaluate and
assignment compatibility is checked in .../lib/Semantics, I moved the common
code into .../lib/Evaluate/tools.cpp and changed the assignment compatibility
checking code to call it.

After implementing these new checks, tests in resolve53.f90 were failing
because the tests were erroneous.  I fixed these tests and added new tests
to call03.f90 to test argument passing of parameterized derived types more
completely.

Differential Revision: https://reviews.llvm.org/D100989
2021-04-22 08:49:49 -07:00
peter klausler 0d8331c06b [flang] Refine symbol sorting
Replace semantics::SymbolSet with alternatives that clarify
whether the set should order its contents by source position
or not.  This matters because positionally-ordered sets must
not be used for Symbols that might be subjected to name
replacement during name resolution, and address-ordered
sets must not be used (without sorting) in circumstances
where the order of their contents affects the output of the
compiler.

All set<> and map<> instances in the compiler that are keyed
by Symbols now have explicit Compare types in their template
instantiations.  Symbol::operator< is no more.

Differential Revision: https://reviews.llvm.org/D98878
2021-03-18 11:18:14 -07:00
peter klausler 46ade6d0ef [flang] Order Symbols by source provenance
In parser::AllCookedSources, implement a map from CharBlocks to
the CookedSource instances that they cover.  This permits a fast
Find() operation based on std::map::equal_range to map a CharBlock
to its enclosing CookedSource instance.

Add a creation order number to each CookedSource.  This allows
AllCookedSources to provide a Precedes(x,y) predicate that is a
true source stream ordering between two CharBlocks -- x is less
than y if it is in an earlier CookedSource, or in the same
CookedSource at an earlier position.

Add a reference to the singleton SemanticsContext to each Scope.

All of this allows operator< to be implemented on Symbols by
means of a true source ordering.  From a Symbol, we get to
its Scope, then to the SemanticsContext, and then use its
AllCookedSources reference to call Precedes().

Differential Revision: https://reviews.llvm.org/D98743
2021-03-16 15:25:15 -07:00
peter klausler bbd0dc3d65 [flang] Ensure pointer function results are acceptable variables
Fortran permits a reference to a function whose result is a pointer
to be used as a definable variable in any context where a
designator could appear.  This patch wrings out remaining bugs
with such usage and adds more testing.

The utility predicate IsProcedurePointer(expr) had a misleading
name which has been corrected to IsProcedurePointerTarget(expr).

Differential Revision: https://reviews.llvm.org/D98555
2021-03-12 16:04:36 -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 24e8e21f19 [flang] Refine WhyNotModifiable()
The utility routine WhyNotModifiable() needed to become more
aware of the use of pointers in data-refs; the targets of
pointer components are sometimes modifiable even when the
leftmost ("base") symbol of a data-ref is not.

Added a new unit test for WhyNotModifiable() that uses internal
READ statements (mostly), since I/O semantic checking uses
WhyNotModifiable() for all its definability checking.

Differential Revision: https://reviews.llvm.org/D94849
2021-01-19 11:44:51 -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 Steinfeld 9168a0f515 [flang] Fix bogus message on index-names in the presence of associated entities
The semantic analysis of index-names of FORALL statements looks up symbols with
the same name as the index-name.  This is needed to exclude symbols that are
not objects.  But if the symbol found is host-, use-, or construct-associated
with another entity, the check fails.

I fixed this by getting the root symbol of the symbol found and doing the check
on the root symbol.  This required creating a non-const version of
"GetAssociationRoot()".

Differential Revision: https://reviews.llvm.org/D92970
2020-12-10 07:36:41 -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 df62afd559 [flang] Unsplit COMPLEX operations
COMPLEX negation, addition, subtraction, conversions of kind, and
equality/inequality were represented as component-wise REAL
operations.  It turns out to be easier for lowering if we
do not split and recombine these COMPLEX operations, and it
avoids a potential problem with COMPLEX valued function calls
in these contexts.  So add this suite of operations to the
typed expression representation in place of the component-wise
transformations, and support them in folding.

Differential revision: https://reviews.llvm.org/D91443
2020-11-16 09:39:03 -08:00
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 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
Riccardo Bertossa c2921d148e [flang] SAVE statement should not apply to nested scoping units
SAVE statement, according to 8.6.14, must apply to the same scoping
unit, that excludes nested scoping units. For example, if the SAVE
statement is found in a MODULE, the functions contained in that module
should not inherit the SAVE attribute. I think that the code was doing
this, failing the following source:

```
MODULE pippo
SAVE

CONTAINS
PURE FUNCTION fft_stick_index( )
   IMPLICIT NONE
   INTEGER :: fft_stick_index
   INTEGER :: mc  !error: A pure subprogram may not have a variable with the SAVE attribute
END FUNCTION

END MODULE
```

Differential Revision: https://reviews.llvm.org/D88279
2020-09-26 12:42:14 -07:00
Tim Keith 82edd428f1 [flang] Fix check for distinguishable operators/assignments
Change how generic operators and assignments are checked for
distinguishable procedures. Because of how they are invoked, available
type-bound generics and normal generics all have to be considered
together. This is different from how generic names are checked.

Move common part of checking into DistinguishabilityHelper so that it
can be used in both cases after the appropriate procedures have been
added.

Cache result of Procedure::Characterize(Symbol) in a map in
CheckHelper so that we don't have to worry about passing the
characterized Procedures around or the cost of recomputing them.

Add MakeOpName() to construct names for defined operators and assignment
for using in error messages. This eliminates the need for different
messages in those cases.

When the procedures for a defined operator or assignment are undistinguishable,
include the type name in the error message, otherwise it may be ambiguous.

Add missing check that procedures for defined operators are functions
and that their dummy arguments are INTENT(IN) or VALUE.

Differential Revision: https://reviews.llvm.org/D87341
2020-09-10 07:22:55 -07:00
peter klausler f862d85807 [flang] Check shape conformance on initializers
Specifically, ensure that initializers conform with their objects
according to 8.2 para 4.

Differential Revision: https://reviews.llvm.org/D86886
2020-08-31 16:27:06 -07:00
Tim Keith a3538b8394 [flang] Improve error messages for procedures in expressions
When a procedure name was used on the RHS of an assignment we were not
reporting the error. When one was used in an expression the error
message wasn't very good (e.g. "Operands of + must be numeric; have
INTEGER(4) and untyped").

Detect these cases in ArgumentAnalyzer and emit better messages,
depending on whether the named procedure is a function or subroutine.

Procedure names may appear as actual arguments to function and
subroutine calls so don't report errors in those cases. That is the same
case where assumed type arguments are allowed, so rename `isAssumedType_`
to `isProcedureCall_` and use that to decide if it is an error.

Differential Revision: https://reviews.llvm.org/D86107
2020-08-18 10:47:55 -07:00
peter klausler e5caa6b5ab [flang] Correct manipulation of mixed complex expressions
Ensure that mixed complex expressions (one operand complex,
the other not) are properly manipulated; add test.
2020-08-13 09:04:00 -07:00
peter klausler 8a8bb078a3 [flang] Fix frontend build with -DBUILD_SHARED_LIBS=On
Fix fronted shared library builds by eliminating dependences of
the parser on other component libraries, moving some code around that
wasn't in the right library, and making some dependences
explicit in the CMakeLists.txt files.  The lowering library
does not yet build as a shared library due to some undefined
names.

Reviewed By: tskeith

Differential Revision: https://reviews.llvm.org/D83515
2020-07-09 15:54:19 -07:00
Tim Keith 663860f63e [flang] Fix bug checking SAVE attribute
Treat function result like dummy argument: a SAVE statement without an
entity-list does not make it saved.

Differential Revision: https://reviews.llvm.org/D82309
2020-06-22 11:33:04 -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 14f49599cc [flang][NFC] Remove link-time dependency of Evaluate on Semantics
Summary:
Some Symbol-related functions used in Evaluate were moved to
Evaluate/tools.h. This includes changing some member functions that were
replaced by non-member functions `IsDummy`, `GetUsedModule`, and
`CountLenParameters`.

Some member functions were made inline in `Scope`, `Symbol`,
`ArraySpec`, and `DeclTypeSpec`. The definitions were preceded by a
comment explaining why they are inline.

`IsConstantShape` was expanded inline in `IsDescriptor` because it isn't
used anywhere else

After this change, at least when compiling with clang on macos,
`libFortranEvaluate.a` has no undefined symbols that are satisfied by
`libFortranSemantics.a`.

Reviewers: klausler, PeteSteinfeld, sscalpone, jdoerfert, DavidTruby

Reviewed By: PeteSteinfeld

Subscribers: llvm-commits

Tags: #flang, #llvm

Differential Revision: https://reviews.llvm.org/D80762
2020-05-29 16:39:14 -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
peter klausler 84a099df05 [flang] Fix missing substring bounds (bug flang-compiler/f18#1091)
Original-commit: flang-compiler/f18@3b0c150b2e
Reviewed-on: https://github.com/flang-compiler/f18/pull/1093
2020-03-27 14:17:25 -07:00
Tim Keith a0a1f519c0 [flang] Perform definability checks on LHS of assignment
If the pure context check succeeds, call `WhyNotModifiable` to verify
the LHS can be modified.

Detect assignment to whole assumed-size array.

Change `IsVariable` to return false for a parameter or a component or
array reference whose base it a parameter.

When analyzing an assignment statement, report an error if the LHS is
a constant expression. Otherwise it might get folded and when we detect
the problem later the error will be confusing.

Handle Substring on LHS of assignment. Change ExtractDataRef and IsVariable
to work on a Substring.

Fix IsImpliedShape and IsAssumedSize predicates in ArraySpec.

Fix C709 check in check-declarations.cpp.

Original-commit: flang-compiler/f18@f2d2657aab
Reviewed-on: https://github.com/flang-compiler/f18/pull/1050
2020-03-09 17:25:12 -07:00
Pete Steinfeld 657aaf8b8d [flang] Semantic checks for C712 through C727
I've updated the compiler and test source with references to the contraints at
the points where they were enforced and tested.  Many of these were already
implemented and required no code change.  A few constraint checks were both
implemented and tested, and I only added references to the constraint
numbers in the compiler source and tests.  Here are the things I had to
implement:

Constraint C716 states that, in a REAL constant, if both a kind-param and an
exponent letter appear, the exponent letter must be 'E'.

Constraints C715 and C719 require that a KIND value be actually implemented.

Constraint C722 requires that functions that return assumed-length character
types are external.

Constraint C726 disallows assumed lenght charater types for dummy arguments and
return types.

Original-commit: flang-compiler/f18@45998741e5
Reviewed-on: https://github.com/flang-compiler/f18/pull/1031
Tree-same-pre-rewrite: false
2020-02-26 20:19:48 -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