Commit Graph

211 Commits

Author SHA1 Message Date
peter klausler e162dc6f28 [flang] Fix symbol table bugs with ENTRY statements
Dummy arguments of ENTRY statements in execution parts were
not being created as objects, nor were they being implicitly
typed.

When the symbol corresponding to an alternate ENTRY point
already exists (by that name) due to having been referenced
in an earlier call, name resolution used to delete the extant
symbol.  This isn't the right thing to do -- the extant
symbol will be pointed to by parser::Name nodes in the parse
tree while no longer being part of any Scope.

Differential Review: https://reviews.llvm.org/D102948
2021-05-21 17:45:37 -07:00
peter klausler cfc12a2120 [flang] Correct the interpretation of BIND(C,NAME='')
An empty NAME= should mean that there is no C binding, not the
binding that would result from BIND(C) without a NAME=.
See 18.10.2p2.

Differential Revision: https://reviews.llvm.org/D100494
2021-04-14 11:33:31 -07:00
peter klausler 5091671c9b [flang] Enforce a limit on recursive PDT instantiations
For pernicious test cases with explicit non-constant actual
type parameter expressions in components, e.g.:

  type :: t(k)
    integer, kind :: k
    type(t(k+1)), pointer :: p
  end type

we should detect the infinite recursion and complain rather
than looping until the stack overflows.

Differential Revision: https://reviews.llvm.org/D100065
2021-04-09 16:38:32 -07:00
Peter Steinfeld a7afc8a514 [flang] Fix CHECK() calls on erroneous procedure declarations
When writing tests for a previous problem, I ran across situations where the
compiler was failing calls to CHECK().  In these situations, the compiler had
inconsistent semantic information because the programs were erroneous.  This
inconsistent information was causing the calls to CHECK().

I fixed this by avoiding the code that ended up making the failed calls to
CHECK() and making sure that we were only avoiding these situations when the
associated symbols were erroneous.

I also added tests that would cause the calls to CHECK() without these changes.

Differential Revision: https://reviews.llvm.org/D99342
2021-03-29 10:12:35 -07:00
Tim Keith 5d3249e9af [flang] Save binding labels as strings
Binding labels start as expressions but they have to evaluate to
constant character of default kind, so they can be represented as an
std::string. Leading and trailing blanks have to be removed, so the
folded expression isn't exactly right anyway.

So all BIND(C) symbols now have a string binding label, either the
default or user-supplied one. This is recorded in the .mod file.

Add WithBindName mix-in for details classes that can have a binding
label so that they are all consistent. Add GetBindName() and
SetBindName() member functions to Symbol.

Add tests that verifies that leading and trailing blanks are ignored
in binding labels and that the default label is folded to lower case.

Differential Revision: https://reviews.llvm.org/D99208
2021-03-24 11:25:23 -07:00
Tim Keith a76d0207d5 Revert "[flang] Save binding labels as strings"
This reverts commit eb4ad0e3e3.

This was causing a crash compiling omp_lib.f90
2021-03-24 09:48:41 -07:00
Tim Keith eb4ad0e3e3 [flang] Save binding labels as strings
Binding labels start as expressions but they have to evaluate to
constant character of default kind, so they can be represented as an
std::string. Leading and trailing blanks have to be removed, so the
folded expression isn't exactly right anyway.

So all BIND(C) symbols now have a string binding label, either the
default or user-supplied one. This is recorded in the .mod file.

Add WithBindName mix-in for details classes that can have a binding
label so that they are all consistent. Add GetBindName() and
SetBindName() member functions to Symbol.

Add tests that verifies that leading and trailing blanks are ignored
in binding labels and that the default label is folded to lower case.

Differential Revision: https://reviews.llvm.org/D99208
2021-03-24 08:52:29 -07:00
Peter Steinfeld e97d92f0bb [flang] Disallow erroneous procedure declarations
When writing tests for a previous problem, I ran across situations where we
were not producing error messages for declarations of specific procedures of
generic interfaces where every other compiler I tested (except nvfotran) did.
I added a check to CheckExtantExternal() and renamed it since it now checks for
erroneous extant symbols generally.

I also removed a call to this function from processing for ENTRY statements,
since it seemed unnecessary and its presence caused bogus error messages.

I also added some tests for erroneous declarations where we were not producing
error messages.

Differential Revision: https://reviews.llvm.org/D99111
2021-03-22 14:52:45 -07:00
Peter Steinfeld 5727df2714 [flang] Specific procedures named the same as the generic and a derived type
If you specify a specific procedure of a generic interface that has the same
name as both the generic interface and a preceding derived type, the compiler
would fail an internal call to CHECK().  I fixed this by testing for this
situation when processing specific procedures.  I also added a test that will
cause the call to CHECK() to fail without this new code.

Differential Revision: https://reviews.llvm.org/D99085
2021-03-22 10:52:50 -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 Steinfeld 1c2935a772 [flang] Prohibit MODULE procedures in the global scope
We were allowing procedures with the MODULE prefix to be declared at the global
scope.  This is prohibited by C1547 and was causing an internal check of the
compiler to fail.

I fixed this by adding a check.  I also added a test that would trigger a crash
without this change.

Differential Revision: https://reviews.llvm.org/D97875
2021-03-03 11:50:50 -08:00
Peter Steinfeld 16005fd979 [flang] Detect circularly defined interfaces of procedures
It's possible to define a procedure whose interface depends on a procedure
which has an interface that depends on the original procedure.  Such a circular
definition was causing the compiler to fall into an infinite loop when
resolving the name of the second procedure.  It's also possible to create
circular dependency chains of more than two procedures.

I fixed this by adding the function HasCycle() to the class DeclarationVisitor
and calling it from DeclareProcEntity() to detect procedures with such
circularly defined interfaces.  I marked the associated symbols of such
procedures by calling SetError() on them.  When processing subsequent
procedures, I called HasError() before attempting to analyze their interfaces.
Unfortunately, this did not work.

With help from Tim, we determined that the SymbolSet used to track the
erroneous symbols was instantiated using a "<" operator which was defined using
the location of the name of the procedure.  But the location of the procedure
name was being changed by a call to ReplaceName() between the times that the
calls to SetError() and HasError() were made.  This caused HasError() to
incorrectly report that a symbol was not in the set of erroneous symbols.

I fixed this by changing SymbolSet to be an unordered set that uses the
contents of the name of the symbol as the basis for its hash function.  This
works because the contents of the name of the symbol is preserved by
ReplaceName() even though its location changes.

I also fixed the error message used when reporting recursively defined
dummy procedure arguments by removing extra apostrophes and sorting the
list of symbols.

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

Note that the "<" operator is used in other contexts, for example, in the map
of characterized procedures, maps of items in equivalence sets, maps of
structure constructor values, ...  All of these situations happen after name
resolution has been completed and all calls to ReplaceName() have already
happened and thus are not subject to the problem I ran into when ReplaceName()
was called when processing procedure entities.

Note also that the implementation of the "<" operator uses the relative
location in the cooked character stream as the basis of its implementation.
This is potentially problematic when symbols from diffent compilation units
(for example symbols originating in .mod files) are put into the same map since
their names will appear in two different source streams which may not be
allocated in the same relative positions in memory.  But I was unable to create
a test that caused a problem.  Using a direct comparison of the content of the
name of the symbol in the "<" operator has problems.  Symbols in enclosing or
parallel scopes can have the same name.  Also using the location of the symbol
in the cooked character stream has the advantage that it preserves the the
order of the symbols in a structure constructor constant, which makes matching
the values with the symbols relatively easy.

This patch supersedes D97749.

Differential Revision: https://reviews.llvm.org/D97774
2021-03-02 15:18:12 -08:00
Peter Steinfeld 95540f9dbf [flang] Detect circularly defined interfaces of procedures
It's possible to define a procedure whose interface depends on a procedure
which has an interface that depends on the original procedure.  Such a circular
definition was causing the compiler to fall into an infinite loop when
resolving the name of the second procedure.  It's also possible to create
circular dependency chains of more than two procedures.

I fixed this by adding the function HasCycle() to the class DeclarationVisitor
and calling it from DeclareProcEntity() to detect procedures with such
circularly defined interfaces.  I marked the associated symbols of such
procedures by calling SetError() on them.  When processing subsequent
procedures, I called HasError() before attempting to analyze their interfaces.
Unfortunately, this did not work.

With help from Tim, we determined that the SymbolSet used to track the
erroneous symbols was instantiated using a "<" operator which was defined using
the location of the name of the procedure.  But the location of the procedure
name was being changed by a call to ReplaceName() between the times that the
calls to SetError() and HasError() were made.  This caused HasError() to
incorrectly report that a symbol was not in the set of erroneous symbols.

I fixed this by changing SymbolSet to be an unordered set that uses the
contents of the name of the symbol as the basis for its hash function.  This
works because the contents of the name of the symbol is preserved by
ReplaceName() even though its location changes.

I also fixed the error message used when reporting recursively defined
dummy procedure arguments by removing extra apostrophes and sorting the
list of symbols.

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

Note that the "<" operator is used in other contexts, for example, in the map
of characterized procedures, maps of items in equivalence sets, maps of
structure constructor values, ...  All of these situations happen after name
resolution has been completed and all calls to ReplaceName() have already
happened and thus are not subject to the problem I ran into when ReplaceName()
was called when processing procedure entities.

Note also that the implementation of the "<" operator uses the relative
location in the cooked character stream as the basis of its implementation.
This is potentially problematic when symbols from diffent compilation units
(for example symbols originating in .mod files) are put into the same map since
their names will appear in two different source streams which may not be
allocated in the same relative positions in memory.  But I was unable to create
a test that caused a problem.  Using a direct comparison of the content of the
name of the symbol in the "<" operator has problems.  Symbols in enclosing or
parallel scopes can have the same name.  Also using the location of the symbol
in the cooked character stream has the advantage that it preserves the the
order of the symbols in a structure constructor constant, which makes matching
the values with the symbols relatively easy.

This patch supersedes D97749.

Differential Revision: https://reviews.llvm.org/D97774
2021-03-02 10:53:44 -08:00
Andrzej Warzynski 1253009eb2 Revert "[flang] Detect circularly defined interfaces of procedures"
This reverts commit 93c5e6bb49.

This patch updates resolve102.f90 which is now failing in 6 out 8 of our
public buildbots:
  * http://lab.llvm.org:8011/#/builders/21/builds/9625
  * http://lab.llvm.org:8011/#/builders/134/builds/2395
  * http://lab.llvm.org:8011/#/builders/79/builds/6298
  * http://lab.llvm.org:8011/#/builders/66/builds/2084
  * http://lab.llvm.org:8011/#/builders/135/builds/2485
  * http://lab.llvm.org:8011/#/builders/32/builds/3551

Please see the following revisions for more context:
  * https://reviews.llvm.org/D97201
  * https://reviews.llvm.org/D97749
2021-03-02 14:55:41 +00:00
Peter Steinfeld 93c5e6bb49 [flang] Detect circularly defined interfaces of procedures
It's possible to define a procedure whose interface depends on a procedure
which has an interface that depends on the original procedure.  Such a circular
definition was causing the compiler to fall into an infinite loop when
resolving the name of the second procedure.  It's also possible to create
circular dependency chains of more than two procedures.

I fixed this by adding the function HasCycle() to the class DeclarationVisitor
and calling it from DeclareProcEntity() to detect procedures with such
circularly defined interfaces.  I marked the associated symbols of such
procedures by calling SetError() on them.  When processing subsequent
procedures, I called HasError() before attempting to analyze their interfaces.
Unfortunately, this did not work.

With help from Tim, we determined that the SymbolSet used to track the
erroneous symbols was instantiated using a "<" operator which was defined using
the location of the name of the procedure.  But the location of the procedure
name was being changed by a call to ReplaceName() between the times that the
calls to SetError() and HasError() were made.  This caused HasError() to
incorrectly report that a symbol was not in the set of erroneous symbols.

I fixed this by changing SymbolSet to be an unordered set that uses the
contents of the name of the symbol as the basis for its hash function.  This
works because the contents of the name of the symbol is preserved by
ReplaceName() even though its location changes.

I also fixed the error message used when reporting recursively defined dummy
procedure arguments.

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

Note that the "<" operator is used in other contexts, for example, in the map
of characterized procedures, maps of items in equivalence sets, maps of
structure constructor values, ...  All of these situations happen after name
resolution has been completed and all calls to ReplaceName() have already
happened and thus are not subject to the problem I ran into when ReplaceName()
was called when processing procedure entities.

Note also that the implementation of the "<" operator uses the relative
location in the cooked character stream as the basis of its implementation.
This is potentially problematic when symbols from diffent compilation units
(for example symbols originating in .mod files) are put into the same map since
their names will appear in two different source streams which may not be
allocated in the same relative positions in memory.  But I was unable to create
a test that caused a problem.  Using a direct comparison of the content of the
name of the symbol in the "<" operator has problems.  Symbols in enclosing or
parallel scopes can have the same name.  Also using the location of the symbol
in the cooked character stream has the advantage that it preserves the the
order of the symbols in a structure constructor constant, which makes matching
the values with the symbols relatively easy.

This change supersedes D97201.

Differential Revision: https://reviews.llvm.org/D97749
2021-03-01 19:07:03 -08:00
Andrzej Warzynski 00e6513374 Revert "[flang] Detect circularly defined interfaces of procedures"
This reverts commit 07de0846a5.

The original patch has caused 6 out 8 of Flang's public buildbots to
fail. As I'm not sure what the fix should be, I'm reverting this for
now. Please see https://reviews.llvm.org/D97201 for more context and
discussion.
2021-03-01 10:34:49 +00:00
Peter Steinfeld 07de0846a5 [flang] Detect circularly defined interfaces of procedures
It's possible to define a procedure whose interface depends on a procedure
which has an interface that depends on the original procedure.  Such a circular
definition was causing the compiler to fall into an infinite loop when
resolving the name of the second procedure.  It's also possible to create
circular dependency chains of more than two procedures.

I fixed this by adding the function HasCycle() to the class DeclarationVisitor
and calling it from DeclareProcEntity() to detect procedures with such
circularly defined interfaces.  I marked the associated symbols of such
procedures by calling SetError() on them.  When processing subsequent
procedures, I called HasError() before attempting to analyze their interfaces.
Unfortunately, this did not work.

With help from Tim, we determined that the SymbolSet used to track the
erroneous symbols was instantiated using a "<" operator which was
defined using the name of the procedure.  But the procedure name was
being changed by a call to ReplaceName() between the times that the
calls to SetError() and HasError() were made.  This caused HasError() to
incorrectly report that a symbol was not in the set of erroneous
symbols.  I fixed this by making SymbolSet be an ordered set, which does
not use the "<" operator.

I also added tests that will crash the compiler without this change.
And I fixed the formatting on an error message from a previous update.

Differential Revision: https://reviews.llvm.org/D97201
2021-02-26 14:44:35 -08:00
peter klausler ea2ff54ccc [flang] Extension: forward refs to dummy args under IMPLICIT NONE
Most Fortran compilers accept the following benign extension,
and it appears in some applications:

  SUBROUTINE FOO(A,N)
    IMPLICIT NONE
    REAL A(N) ! N is used before being typed
    INTEGER N
  END

Allow it in f18 only for default integer scalar dummy arguments.

Differential Revesion: https://reviews.llvm.org/D96982
2021-02-18 13:14:34 -08:00
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 klausler 452d7ebc09 [flang] Ensure that intrinsic procedures are PURE &/or ELEMENTAL
The intrinsic procedure table properly classify the various
intrinsics, but the PURE and ELEMENTAL attributes that these
classifications imply don't always make it to the utility
predicates that test symbols for them, leading to spurious
error messages in some contexts.  So set those attribute flags
as appropriate in name resolution, using a new function to
isolate the tests.

An alternate solution, in which the predicates would query
the intrinsic procedure table for these attributes on demand,
was something I also tried, so that this information could
come directly from an authoritative source; but it would have
required references to the intrinsic table to be passed along
on too many seemingly unrelated APIs and ended up looking messy.

Several symbol table tests needed to have their expected outputs
augmented with the PURE and ELEMENTAL flags.  Some bogus messages
that were flagged as such in test/Semantics/doconcurrent01.f90 were
removed, since they are now correctly not emitted.

Differential Revision: https://reviews.llvm.org/D96878
2021-02-17 11:31:33 -08:00
peter klausler 47b97d4bfb [flang] Manage per-specification-part state better
Some state in name resolution is stored in the DeclarationVisitor
instance and processed at the end of the specification part.
This state needs to accommodate nested specification parts, namely
the ones that can be nested in a subroutine or function interface
body.

Differential Revision: https://reviews.llvm.org/D96466
2021-02-10 17:23:53 -08:00
peter klausler ebe74d9592 [flang] Support disabled alternative PARAMETER statement
Legacy Fortran implementations support an alternative form of the
PARAMETER statement; it differs syntactically from the standard's
PARAMETER statement by lacking parentheses, and semantically by
using the type and shape of the initialization expression to define
the attributes of the named constant.  (GNU Fortran gets that part
wrong; Intel Fortran and nvfortran have full support.)

This patch disables the old style PARAMETER statement by default, as
it is syntactically ambiguous with conforming assignment statements;
adds a new "-falternative-parameter-statement" option to enable it;
and implements it correctly when enabled.

Fixes https://bugs.llvm.org/show_bug.cgi?id=48774, in which a user
tripped over the syntactic ambiguity.

Differential Revision: https://reviews.llvm.org/D95697
2021-01-29 15:30:06 -08:00
peter klausler 3738447c96 [flang] Address name resolution problems
Don't emit a bogus error message about a bad forward reference
when it's an IMPORT of a USE-associated symbol; don't ignore
intrinsic functions when USE-associating the contents of a
module when the intrinsic has been explicitly USE'd; allow
PUBLIC or PRIVATE accessibility attribute to be specified
for an enumerator before the declaration of the enumerator.

Differential Revision: https://reviews.llvm.org/D95175
2021-01-21 16:15:38 -08:00
Peter Steinfeld bebbe64075 [flang] Fix creation of deferred shape arrays by POINTER statement
It's possible to  declare deferred shape array using the POINTER
statement, for example:

  POINTER :: var(:)

When analyzing POINTER declarations, we were not capturing the array
specification information, if present.  I fixed this by changing the
"Post" function for "parser::PointerDecl" to check to see if the
declaration contained a "DeferredShapeSpecList".  In such cases, I
analyzed the shape and used to information to declare an "ObjectEntity"
that contains the shape information rather than an "UnknownEntity".

I also added a couple of small tests that fail to compile without these
changes.

Differential Revision: https://reviews.llvm.org/D95080
2021-01-20 13:08:11 -08:00
peter klausler ff3b51b054 [flang] Fix ASSOCIATE statement name resolution
F18 Clause 19.4p9 says:

  The associate names of an ASSOCIATE construct have the scope of the
  block.

Clause 11.3.1p1 says the ASSOCIATE statement is not itself in the block:

  R1102 associate-construct is:  associate-stmt block end-associate-stmt

Associate statement associations are currently fully processed from left
to right, incorrectly interposing associating entities earlier in the
list on same-named entities in the host scope.

    1  program p
    2    logical :: a = .false.
    3    real :: b = 9.73
    4    associate (b => a, a => b)
    5      print*, a, b
    6    end associate
    7    print*, a, b
    8  end

Associating names 'a' and 'b' at line 4 in this code are now both
aliased to logical host entity 'a' at line 2.  This happens because the
reference to 'b' in the second association incorrectly resolves 'b' to
the entity in line 4 (already associated to 'a' at line 2), rather than
the 'b' at line 3.  With bridge code to process these associations,
f18 output is:

 F F
 F 9.73

It should be:

 9.73 F
 F 9.73

To fix this, names in right-hand side selector variables/expressions
must all be resolved before any left-hand side entities are resolved.
This is done by maintaining a stack of lists of associations, rather
than a stack of associations.  Each ASSOCIATE statement's list of
assocations is then visited once for right-hand side processing, and
once for left-hand side processing.

Note that other construct associations do not have this problem.
SELECT RANK and SELECT TYPE each have a single assocation, not a list.
Constraint C1113 prohibits the right-hand side of a CHANGE TEAM
association from referencing any left-hand side entity.

Differential Revision: https://reviews.llvm.org/D95010
2021-01-20 11:18:27 -08:00
peter klausler 1bd083b5d6 [flang] Create names to allow access to inaccessible specifics
When a reference to a generic interface occurs in a specification
expression that must be emitted to a module file, we have a problem
when the generic resolves to a function whose name is inaccessible
due to being PRIVATE or due to a conflict with another use of the
same name in the scope.  In these cases, construct a new name for
the specific procedure and emit a renaming USE to the module file.
Also, relax enforcement of PRIVATE when analyzing module files.

Differential Revision: https://reviews.llvm.org/D94815
2021-01-15 16:56:38 -08:00
Tim Keith d6acf3c201 [flang] Fix use-associated procedure in generic
When a use-associated procedure was included in a generic, we weren't
correctly recording that fact. The ultimate symbol was added rather than
the local symbol.

Also, improve the message emitted for the specific procedure by
mentioning the module it came from.

This fixes one of the problems in https://bugs.llvm.org/show_bug.cgi?id=48648.

Differential Revision: https://reviews.llvm.org/D94696
2021-01-14 16:31:52 -08:00
peter klausler 166e5c335c [flang] Do not create HostAssoc symbols in derived type scopes
When needed due to a specification expression in a derived type,
the host association symbols should be created in the surrounding
subprogram's scope instead.

Differential Revision: https://reviews.llvm.org/D94567
2021-01-13 11:01:27 -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
Tim Keith f782d5ea86 [flang] Detect call to abstract interface
A subroutine call or function reference to an abstract interface is
not legal.

Differential Revision: https://reviews.llvm.org/D93872
2020-12-28 16:36:34 -08:00
Tim Keith d55627d221 [flang] Fix bugs in .mod file for abstract interface
When an abstract interface is defined, add the ABSTRACT attribute to
subprogram symbols that define the interface body. Make use of that
when writing .mod files to include "abstract" on the interface statement.

Also, fix a problem with the order of symbols in a .mod file. Sometimes
a name is mentioned before the "real" declaration, e.g. in an access
statement. We want the order to be based on the real definitions. In
these cases we replace the symbol name with an identical name with a
different source location. Then by sorting based on the source location
we get symbols in the right order.

Differential Revision: https://reviews.llvm.org/D93572
2020-12-28 08:50:32 -08:00
Tim Keith bf0870d864 [flang] Fix bug in IMPLICIT NONE(EXTERNAL)
We were only checking the restrictions of IMPLICIT NONE(EXTERNAL) when a
procedure name is first encountered. But it can also happen with an
existing symbol, e.g. if an external function's return type is declared
before is it called. This change adds a check in that branch too.

Differential Revision: https://reviews.llvm.org/D93552
2020-12-18 17:43:53 -08:00
Peter Steinfeld 4e90cad6a6 [flang] Handle undeclared names in EQUIVALENCE statements
Names in EQUIVALENCE statements are only allowed to indicate local
objects as per 19.5.1.4, paragraph 2, item (10).  Thus, a name appearing
in an EQUIVALENCE statement with no corresponding declaration in the
same scope is an implicit declaration of the name.  If that scope
contains an IMPLICIT NONE, it's an error.

I implemented this by adding a state variable to ScopeHandler to
indicate if we're resolving the names in an EQUIVALENCE statement and
then checked this state when resolving names.  I also added a test to
the existing tests for EQUIVALENCE statements.

Differential Revision: https://reviews.llvm.org/D93345
2020-12-16 11:04:27 -08:00
Tim Keith 7082de56b7 [flang] Handle multiple names for same operator
Some operators have more than one name, e.g. operator(==), operator(.eq).
That was working correctly in generic definitions but they can also
appear in other contexts: USE statements and access statements, for
example.

This changes FindInScope to always look for each of the names for
a symbol. So an operator may be use-associated under one name but
declared private under another name and it will be the same symbol.
This replaces GenericSpecInfo::FindInScope which was only usable in
some cases.

Add a version of FindInScope() that looks in the current scope to
simplify many of the calls.

Differential Revision: https://reviews.llvm.org/D93344
2020-12-16 07:06:55 -08:00
Tim Keith 3a0352b85c [flang] Fix bug with USE of USE of generic
When merging use associations into a generic, we weren't handling
the case where the name that was use associated was itself a use
association. This is fixed by following that association to its
ultimate symbol (`useUltimate` in `DoAddUse`).

An example of the bug is `m12d` in `resolve17.f90`. `g` is associated
with `gc` in `m12c` which is associated with `gb` in `m12b`. It was that
last association that we weren't correctly following.

Differential Revision: https://reviews.llvm.org/D93343
2020-12-15 16:11:59 -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 Steinfeld f24c642178 [flang] Fix bogus message on interface procedure argument names
We were keeping the state of parsed equivalence sets in the class
DeclarationVisitor.  A problem happened when  analyzing the the specification
part of a declaration that contained an EQUIVALENCE statement followed by an
interface block.  The same DeclarationVisitor object that was created for the
outer declaration was being used to analyze the specification part
of a procedure body in the interface block.  When analyzing the specification
part of the procedure in the interface block, the names in the outer
declaration's EQUIVALENCE statement were erroneously compared with the names in
the arguments of the interface procedure.  This resulted in a bogus error
message.

I fixed this by not checking equivalence sets when we're in an interface
block.  I also added a test that will produce an error message without
this change.

Differential Revision: https://reviews.llvm.org/D92501
2020-12-03 12:08:55 -08:00
Tim Keith 86f59de13b [flang] Fix bugs related to merging generics during USE
When the same generic name is use-associated from two modules, the
generics are merged into a single one in the current scope. This change
fixes some bugs in that process.

When a generic is merged, it can have two specific procedures with the
same name as the generic (c.f. module m7c in modfile07.f90). We were
disallowing that by checking for duplicate names in the generic rather
than duplicate symbols. Changing `namesSeen` to `symbolsSeen` in
`ResolveSpecificsInGeneric` fixes that.

We weren't including each USE of those generics in the .mod file so in
some cases they were incorrect. Extend GenericDetails to specify all
use-associated symbols that are merged into the generic. This is used to
write out .mod files correctly.

The distinguishability check for specific procedures of a generic
sometimes have to refer to procedures from a use-associated generic in
error messages. In that case we don't have the source location of the
procedure so adapt the message to say where is was use-associated from.
This requires passing the scope through the checks to make that
determination.

Differential Revision: https://reviews.llvm.org/D92492
2020-12-02 15:13:50 -08:00
Tim Keith 1f525ece4a [flang][NFC] Add GetTopLevelUnitContaining functions
`GetTopLevelUnitContaining` returns the Scope nested in the global scope
that contains the given Scope or Symbol.

Use "Get" rather than "Find" in the name because "Find" implies it might
not be found, which can't happen. Following that logic, rename
`FindProgramUnitContaining` to `GetProgramUnitContaining` and have it
also return a reference rather that a pointer.

Note that the use of "ProgramUnit" is slightly confusing. In the Fortran
standard, "program-unit" refers to what is called a "TopLevelUnit" here.
What we are calling a "ProgramUnit" (here and in `ProgramTree`) includes
internal subprograms while "TopLevelUnit" does not.

Differential Revision: https://reviews.llvm.org/D92491
2020-12-02 10:28:49 -08:00
Praveen G 7a91794d5b [Flang][OpenMP] Add semantic checks for OpenMP Private clause.
Add the semantic checks for the OpenMP 4.5 - 2.15.3.3 Private clause.

1. Pointers with the INTENT(IN) attribute may not appear in a private clause.
2. Variables that appear in namelist statements may not appear in a private clause.
   A flag 'InNamelist' is added to the Symbol::Flag to identify the symbols
   in Namelist statemnts.

Test cases : omp-private01.f90, omp-private02.f90

Reviewed By: kiranchandramohan

Differential Revision: https://reviews.llvm.org/D90210
2020-11-30 11:46:36 -05:00
peter klausler 5349f99114 [flang] Correct handling of null pointer initializers
Fortran defines "null-init" null pointer initializers as
being function references, syntactically, that have to resolve
to calls to the intrinsic function NULL() with no actual
arguments.

Differential revision: https://reviews.llvm.org/D91657
2020-11-18 13:57:25 -08:00
Peter Steinfeld 681978d3b4 [flang] Duplicate names for ac-implied-do variables erroneously cause errors
According to section 19.4, paragraph 5, the scope of an ac-implied-do variable
is the enclosing ac-implied-do.  But we were not creating new scopes upon
entry to an ac-implied-do.  This was causing error messages to be erroneously
emitted.

I fixed, the code, added a test to array-constr-values.f90, added the test
folding15.f90 and corrected the test symbol05.f90.

Differential Revision: https://reviews.llvm.org/D91560
2020-11-16 18:57:13 -08:00
peter klausler 2d5b850751 [flang] Use IMPLICIT from scope of external function reference
Implicitly typed references to external functions are applying
the IMPLICIT typing rules of the global scope in which their
symbols were created, not the IMPLICIT typing rules in force in
the scope from which they were referenced.

Differential revision: https://reviews.llvm.org/D91214
2020-11-11 12:12:24 -08:00
peter klausler 882fa241f1 [flang] Better error messages & more cases caught for bad forward refs
Subclause 10.1.12 in F'2018 prohibits forward references from
a specification expression to an object declared later in the
same specification part.  Catch this error better and emit
specific error messages about the violation.

Differential revision: https://reviews.llvm.org/D90492
2020-10-30 17:11:37 -07:00
Jean Perier 878b526409 [flang] Tighten rules to resolve procedure as intrinsic procedure
2 Bug fixes:

- Do not resolve procedure as intrinsic if they appeared in an
  EXTERNAL attribute statement (one path was not considering this flag)

- Emit an error if a procedure resolved to be an intrinsic function
  (resp. subroutine) is used as a subroutine (resp. function).
  Lowering was attempted while the evaluate::Expression for the
  call was missing without any errors.

1 behavior change:

- Do not implicitly resolve subroutines (resp. functions) as intrinsics
  because their name is the name of an intrinsic function (resp.
  subroutine). Add justification in documentation.

Reviewed By: klausler, tskeith

Differential Revision: https://reviews.llvm.org/D90049
2020-10-26 11:25:40 +01:00
Peter Steinfeld 29d838310d [flang] Fix call to CHECK() on erroneous subroutine declaration
When processing declarations in resolve-names.cpp, we were returning a
symbol that had SubprogramName details to PushSubprogramScope(), which
expects a symbol with Subprogram details.

I adjusted the code and added a test.

Differential Revision: https://reviews.llvm.org/D89829
2020-10-20 18:09:15 -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
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
compinder 5ec043eae1 [FLANG] Generate error for invalid selector.
Fix of PR47339

Differential Revision: https://reviews.llvm.org/D87073/new/
2020-09-09 19:14:54 +05:30
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 627e9007ea [flang][NFC] Change how error symbols are recorded
When an error is associated with a symbol, it was marked with a flag
from Symbol::Flag. The problem with that is that you need a mutable
symbol to do that. Instead, store the set of error symbols in the
SemanticsContext. This allows for some const_casts to be eliminated.

Also, improve the internal error that occurs if SetError is called
but no fatal error has been reported.

Differential Revision: https://reviews.llvm.org/D86740
2020-08-28 10:30:25 -07:00
peter klausler 13cee14bb1 [flang] Parse global compiler directives
Accept and represent "global" compiler directives that appear
before and between program units in a source file.

Differential Revision: https://reviews.llvm.org/D86555
2020-08-25 11:41:11 -07:00
Tim Keith b8bfe3586e [flang] Fix bug accessing implicit variable in specification expression
A specification expression can reference an implicitly declared variable
in the host procedure. Because we have to process specification parts
before execution parts, this may be the first time we encounter the
variable. We were assuming the variable was implicitly declared in the
scope where it was encountered, leading to an error because local
variables may not be referenced in specification expressions.

The fix is to tentatively create the implicit variable in the host
procedure because that is the only way the specification expression can
be valid. We mark it with the flag `ImplicitOrError` to indicate that
either it must be implicitly defined in the host (by being mentioned in
the execution part) or else its use turned out to be an error.
We need to apply the implicit type rules of the host, which requires
some changes to implicit typing.

Variables in common blocks are allowed to appear in specification expressions
(because they are not locals) but the common block definition may not appear
until after their use. To handle this we create common block symbols and object
entities for each common block object during the `PreSpecificationConstruct`
pass. This allows us to remove the corresponding code in the main visitor and
`commonBlockInfo_.curr`. The change in order of processing causes some
different error messages to be emitted.

Some cleanup is included with this change:
- In `ExpressionAnalyzer`, if an unresolved name is encountered but
  no error has been reported, emit an internal error.
- Change `ImplicitRulesVisitor` to hide the `ImplicitRules` object
  that implements it. Change the interface to pass in names rather
  than having to get the first character of the name.
- Change `DeclareObjectEntity` to have the `attrs` argument default
  to an empty set; that is the typical case.
- In `Pre(parser::SpecificationPart)` use "structured bindings" to
  give names to the pieces that make up a specification-part.
- Enhance `parser::Unwrap` to unwrap `Statement` and `UnlabeledStatement`
  and make use of that in PreSpecificationConstruct.

Differential Revision: https://reviews.llvm.org/D86322
2020-08-24 12:53:46 -07:00
Tim Keith c0c3cafa2b [flang] Fix assert on bad character kind
When we report an error for a bad character kind, don't keep it in the
`DeclTypeSpec`. Otherwise there could be further problems. In this case,
`ComputeOffsets()` got an assertion error because we didn't recognize
`CHARACTER(*,8)` as needing a descriptor because of the bad kind.

Fixes https://bugs.llvm.org/show_bug.cgi?id=47173

Differential Revision: https://reviews.llvm.org/D86357
2020-08-22 10:11:38 -07:00
Tim Keith d66463eedc [flang] Copy attributes and flags onto host-assoc symbols
As with use-associated symbols, copy the attributes and flags from the
original symbol onto host-associated symbols when they are created.

This was showing up as an error on a deallocate of a host-associated
name. We reported an error because the symbol didn't have the POINTER
or ALLOCATABLE attribute.

Differential Revision: https://reviews.llvm.org/D85763
2020-08-17 07:00:07 -07:00
Tim Keith f5e4451e1f [flang] Fix interpretation of intrinsic names as arguments
If an unrestricted specific intrinsic function name is first encountered
as an actual argument, it should be interpreted as an object entity,
not a procedure entity.

Fix some tests that depended on the previous interpretation by adding
explicit INTRINSIC statements.

Differential Revision: https://reviews.llvm.org/D85792
2020-08-11 16:52:50 -07:00
Tim Keith cf715717aa [flang] Allow compiler directives in more places
Allow compiler directives in the implicit-part and before USE statements
in the specification-part.

Differential Revision: https://reviews.llvm.org/D85693
2020-08-11 08:37:27 -07:00
peter klausler 0e9e06a6d4 [flang][NFC] Reformat files with current clang-format
Differential Revision: https://reviews.llvm.org/D85489
2020-08-07 12:10:26 -07:00
Tim Keith 08c7d570d3 [flang] Add options to control IMPLICIT NONE
Add `-fimplicit-none-type-always` to treat each specification-part
like it has `IMPLICIT NONE`. This is helpful for enforcing good Fortran
programming practices. We might consider something similar for
`IMPLICIT NONE(EXTERNAL)` as well.

Add `-fimplicit-none-type-never` to ignore occurrences of `IMPLICIT NONE`
and `IMPLICIT NONE(TYPE)`. This is to handle cases like the one below,
which violates the standard but it accepted by some compilers:
```
subroutine s(a, n)
  implicit none
  real :: a(n)
  integer :: n
end
```

Differential Revision: https://reviews.llvm.org/D85363
2020-08-06 06:48:01 -07:00
Tim Keith 0d454e8e08 [flang] Fix bug detecting intrinsic function
Don't set the INTRINSIC attribute on a dummy procedure.

Differential Revision: https://reviews.llvm.org/D85136
2020-08-03 12:21:59 -07:00
sameeran joshi b752a8ca49 [flang][NFC] Verify C781 from - Clause 7 constraint checks for f18.
Reviewed By: PeteSteinfeld

Differential Revision: https://reviews.llvm.org/D84503
2020-07-31 23:58:18 +05:30
Peter Steinfeld fac84536bc [flang] Fix an assert on duplicate initializations
When declaring the same variable twice with an initialization, we were failing
an internal check.  I fixed this by checking to see if the associated symbol
already had an error.

I added tests for pointer and non-pointer initialization of duplicate names.

Differential Revision: https://reviews.llvm.org/D84969
2020-07-30 12:58:28 -07:00
Tim Keith 38272f45fe [flang] Create HostAssoc symbols for uplevel references
To make it easier for lowering to identify which symbols from the host
are captured by internal subprograms, create HostAssocDetails for them.

In particular, if a symbol is referenced and it is contained in a
subprogram or main program that is not the same as the containing
program unit of the reference, a HostAssocDetails symbol is created
in the current scope.

Differential Revision: https://reviews.llvm.org/D84889
2020-07-30 07:12:26 -07:00
Tim Keith 2c662f3d3d [flang] Fix bug with intrinsic in type declaration stmt
When an instrinsic function is declared in a type declaration statement
we need to set the INTRINSIC attribute and (per 8.2(3)) ignore the
specified type.

To simplify the check, add IsIntrinsic utility to BaseVisitor.

Also, intrinsics and external procedures were getting assigned a size
and offset and they shouldn't be.

Differential Revision: https://reviews.llvm.org/D84702
2020-07-29 07:23:31 -07:00
Tim Keith 9500d48de3 [flang][NFC] Extract name resolution for OpenACC & OpenMP into new file
Move `ResolveAccParts` and `ResolveOmpParts` from resolve-names.cpp to
resolve-directives.{h,cpp}. Move the implementation in the classes
`DirectiveAttributeVisitor`, `AccAttributeVisitor`, and
`OmpAttributeVisitor` to resolve-directives.cpp as well.

To allow this to happen, move `EvaluateIntExpr` and introduce
`EvaluateInt64` to resolve-names-utils.h. The latter is also useful
elsewhere in resolve-names.cpp for converting an Expr to std::int64_t.

The other problem was that `ResolveDesignator` was called from the code
that was moved. At the moment it doesn't seem to be doing anything so I
removed the calls (and no tests failed). If it proves to be needed, we
can either resolve those designators in resolve-names.cpp or pass the
`ResolveDesignator` function in to the code that needs to call it.

Differential Revision: https://reviews.llvm.org/D84768
2020-07-28 16:38:36 -07:00
Valentin Clement ff25b2da2a [flang][openacc] Basic name resolution infrastructure for OpenACC construct
Reviewed By: tskeith, klausler, ichoyjx

Differential Revision: https://reviews.llvm.org/D83998
2020-07-26 20:01:35 -04:00
Tim Keith 7454acdf3b [flang] Fix implicit declarations in statement functions
If a symbol (that is not a dummy argument) is implicitly declared inside
a statement function, don't create it in the statement function's scope.
Instead, treat statement functions like blocks when finding the inclusive
scope and create the symbol there.

Add a new flag, StmtFunction, to symbols that represent statement functions.

Differential Revision: https://reviews.llvm.org/D84588
2020-07-26 12:13:39 -07:00
Tim Keith 412056e2d0 [flang] Implicitly convert result of statement function
The result of a statement function may require an implicit conversion
to match its result type. Add that to the expression that represents
the statement function body in SubprogramDetails.

Extract the analysis of that expression into a separate function.

Dump the statement function expression as part of the dump of
SubprogramDetails.

Differential Revision: https://reviews.llvm.org/D84452
2020-07-23 17:15:35 -07:00
Tim Keith fa5e4482e0 [flang] Don't use-associate intrinsics
When an intrinsic is referenced in a module scope, a symbol for it is
added. When that module is USEd, the intrinsic should not be included.
Otherwise we can get ambiguous reference errors with the same intrinsic
coming from two difference modules.

Differential Revision: https://reviews.llvm.org/D83905
2020-07-15 15:08:08 -07:00
Tim Keith b297563a75 [flang] Fix erroneous application of SAVE statement
A SAVE statement with no entity list applies the SAVE attribute only to
the entities that it is allowed on. We were applying it to automatic
data objects and reporting an error that they can't have SAVE.

The fix is to change `DeclarationVisitor::CheckSaveAttr` to check for
automatic objects. That controls both checking and setting the
attribute. This allows us to remove the check from `CheckSpecExpr`
(along with `symbolBeingChecked_`). Also, it was only called on constant
objects so the non-const overload can be eliminated.

The check in `CheckSpecExpr` is replaced by an explicit check for
automatic objects in modules. This caught an error in modfile03.f90 so
that part of the test was eliminated.

Differential Revision: https://reviews.llvm.org/D83899
2020-07-15 13:02:33 -07:00
Valentin Clement 0a90ffa772 [flang][openacc] OpenACC 3.0 parser
Summary:
This patch introduce the parser for OpenACC 3.0 in Flang. It uses the same TableGen mechanism
than OpenMP.

Reviewers: nvdatian, sscalpone, tskeith, klausler, ichoyjx, jdoerfert, DavidTruby

Reviewed By: klausler

Subscribers: MaskRay, SouraVX, mgorny, hiraditya, jfb, sstefan1, llvm-commits

Tags: #llvm, #flang

Differential Revision: https://reviews.llvm.org/D83649
2020-07-14 14:29:40 -04:00
Valentin Clement f06ad91347 Revert "[flang][openacc] OpenACC 3.0 parser"
This reverts commit 65049d1610.

Buildbot failure clang-ppc64le-rhel
2020-07-13 22:35:19 -04:00
Valentin Clement 65049d1610 [flang][openacc] OpenACC 3.0 parser
Summary:
This patch introduce the parser for OpenACC 3.0 in Flang. It uses the same TableGen mechanism
than OpenMP.

Reviewers: nvdatian, sscalpone, tskeith, klausler, ichoyjx, jdoerfert, DavidTruby

Reviewed By: klausler

Subscribers: SouraVX, mgorny, hiraditya, jfb, sstefan1, llvm-commits

Tags: #llvm, #flang

Differential Revision: https://reviews.llvm.org/D83649
2020-07-13 20:15:06 -04:00
Pete Steinfeld f9e24a563c [flang] Bug fix for ambiguous references to data and functions
Summary:
A program may erroneously reference the same name as both a data object
and as a function.  Some of these references were causing an internal
error in expression analysis.

It was already the case that a symbol referenced in a parse tree for a
call was changed from an `Entity` to a `ProcEntity`.  I added code to
detect when a symbol was referenced in a parse tree as an array element
gets changed from an `Entity` to an `ObjectEntity`.  Then, if an
`ObjectEntity` gets called as a function or a `ProcEntity` gets
referenced as a data object, errors get emitted.

This analysis was previously confined to the name resolution of the
specification part of a `ProgramTree`.  I added a pass to the execution
part of a `ProgramTree` to catch names declared in blocks.

Reviewers: tskeith, klausler, DavidTruby

Subscribers: llvm-commits

Tags: #llvm, #flang

Differential Revision: https://reviews.llvm.org/D82903
2020-07-06 11:27:14 -07:00
Valentin Clement 2ddba3082c [flang][openmp] Use common Directive and Clause enum from llvm/Frontend
Summary:
This patch is removing the custom enumeration for OpenMP Directives and Clauses and replace them
with the newly tablegen generated one from llvm/Frontend. This is a first patch and some will follow to share the same
infrastructure where possible. The next patch should use the clauses allowance defined in the tablegen file.

Reviewers: jdoerfert, DavidTruby, sscalpone, kiranchandramohan, ichoyjx

Reviewed By: DavidTruby, ichoyjx

Subscribers: jholewinski, cfe-commits, dblaikie, MaskRay, ymandel, ichoyjx, mgorny, yaxunl, guansong, jfb, sstefan1, aaron.ballman, llvm-commits

Tags: #llvm, #flang, #clang

Differential Revision: https://reviews.llvm.org/D82906
2020-07-01 20:58:11 -04:00
clementval 5c37b2a5ee Revert "[flang][openmp] Use common Directive and Clause enum from llvm/Frontend"
This reverts commit 7f1e776795.
2020-07-01 18:49:07 -04:00
Valentin Clement 7f1e776795 [flang][openmp] Use common Directive and Clause enum from llvm/Frontend
Summary:
This patch is removing the custom enumeration for OpenMP Directives and Clauses and replace them
with the newly tablegen generated one from llvm/Frontend. This is a first patch and some will follow to share the same
infrastructure where possible. The next patch should use the clauses allowance defined in the tablegen file.

Reviewers: jdoerfert, DavidTruby, sscalpone, kiranchandramohan, ichoyjx

Reviewed By: DavidTruby, ichoyjx

Subscribers: ichoyjx, mgorny, yaxunl, guansong, jfb, sstefan1, aaron.ballman, llvm-commits

Tags: #llvm, #flang

Differential Revision: https://reviews.llvm.org/D82906
2020-07-01 15:58:45 -04:00
peter klausler f45b41348b [flang] Defer stmt function body analysis until specification part complete
Expression analysis was being invoked on the bodies of statement functions
as they were being encountered during name resolution.  This led to failures
on some FCVS tests in cases where those expressions contained implicitly
typed objects.  Defer the analysis of statemet function bodies to the end
of the specification part, at which time the symbols of the enclosing scope
will have been typed.

Reviewed By: tskeith

Differential Revision: https://reviews.llvm.org/D82796
2020-06-29 12:32:19 -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
David Truby 9362698450 [flang] Change DIE("unreachable") cases to use llvm_unreachable
Reviewers: sscalpone

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D79507
2020-06-15 17:21:35 +01:00
sameeran joshi 70ad73b6b7 [flang] Semantics for SELECT TYPE
Summary:
    Added support for all semantic checks except C1157
    was previously implemented.

    Address review comments.

    Reviewers: PeteSteinfeld, tskeith, klausler, DavidTruby, kiranktp, anchu-rajendran, sscalpone

    Subscribers: kiranchandramohan, llvm-commits, flang-commits

    Tags: #llvm, #flang

    Differential Revision: https://reviews.llvm.org/D79851
2020-06-12 00:12:24 +05:30
Tim Keith a27d385209 [flang] Fix bug resolving type in type definition
When we encountered a type name in a derived type definition, we were
sometimes finding a component of that name rather than the type from
the enclosing scope. Fix this by introducing `NonDerivedTypeScope()` to
start the search in the right scope.

Differential Revision: https://reviews.llvm.org/D81493
2020-06-09 14:14:03 -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
Pete Steinfeld c4dbe59ae8 [flang] Fixes for problems with declaring procedure entities
Summary:
We were not detecting declaring multiple interfaces to the same procedure.
Also, we were not handling the initialization of entitiies where the associated
Symbol had previously had errors.

I added the function `IsInterfaceSet()` to ProcEntityDetails to see if
the value of `interface_` had been previously set.  I then checked  this
function before calling set_interface() and emitted an error message if
the interface was already set.

Also, in situations where we were emitting error messages for symbols, I
set the Error flag on the Symbol.  Then when performing initialization
on the Symbol, I first check to see if the Symbol had an error.

Reviewers: tskeith, klausler, DavidTruby

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D80453
2020-05-26 12:17:20 -07:00
Pete Steinfeld 38095549c6 [flang] Constraint checks C751 to C760
Summary:
Many of these were already implemented, and I just annotated the tests and/or
the code.

C752 was a simple check to verify that CONTIGUOUS components are arrays with

C754 proved to be virtually identical to C750 that I implemented previously.
This caused me to remove the distinction between specification expressions for
type parameters and bounds expressions that I'd previously created.
the POINTER attribute.

I also changed the error messages to specify that errors in specification
expressions could arise from either bad derived type components or type
parameters.

In cases where we detect a type param that was not declared, I created a symbol
marked as erroneous.  That avoids subsequent semantic process for expressions
containing the symbol.  This change caused me to adjust tests resolve33.f90 and
resolve34.f90.  Also, I avoided putting out error messages for erroneous type
param symbols in `OkToAddComponent()` in resolve-names.cpp and in
`EvaluateParameters()`, type.cpp.

C756 checks that procedure components have the POINTER attribute.

Reviewers: tskeith, klausler, DavidTruby

Subscribers: llvm-commits

Tags: #llvm, #flang

Differential Revision: https://reviews.llvm.org/D79798
2020-05-15 18:50:14 -07:00
Valentin Clement 85725a67c7 [Flang][OpenMP] Avoid abort when collapse clause value is negative
Summary:
If the value in the collapse close is negative f18 abort without the correct error message. This PR change the size_t in name resolution to a int64_t and check appropriately for negative or zero before the privatization of induction variable.
The correct error is then catch by the OpenMP structure check.

This diff is migrated from the GitHub pull request https://github.com/flang-compiler/f18/pull/1098

Reviewers: ichoyjx, jdoerfert, sscalpone, DavidTruby

Reviewed By: ichoyjx, sscalpone, DavidTruby

Subscribers: sscalpone, klausler, yaxunl, guansong, llvm-commits

Tags: #llvm, #flang

Differential Revision: https://reviews.llvm.org/D77821
2020-05-14 21:37:25 -04:00
sameeran joshi 332e6aea37 [flang]Semantics for SELECT RANK.
Summary:
    Initially on github I worked on semantic checks.Then I tried some compile-time
    test of the rank value, they were failing as there were no symbols
    generated for them inside SELECT RANK's scope.So I went further to
    add new symbol in each scope, also added the respective 'rank: '
    field for a symbol when we dump the symboltable. I added a field to
    keep track of the rank in AssocEntityDetails class.This caused shape
    analysis framework to become inconsistent. So shape analysis framework
    was updated to handle this new representation.

	 *   I added more tests for above changes.

	 *   On phabricator I addressed some minor changes.

	 *   Lastly I worked on review comments.

    Reviewers: klausler,sscalpone,DavidTruby,kiranchandramohan,tskeith,anchu-rajendran,kiranktp

    Reviewed By:klausler, DavidTruby, tskeith

    Subscribers:#flang-commits, #llvm-commits

    Tags: #flang, #llvm

    Differential Revision: https://reviews.llvm.org/D78623
2020-05-08 08:52:31 +05:30
Tim Keith d5c05ced82 [flang][NFC] Add accessors to equivalence and common blocks
Add a way to get mutable equivalence sets to Scope so that they can
have sizes and offsets assigned to them.

Change CommonBlockDetails to have mutable symbols so that they can have
sizes and offets assigned to them. This also allows the removal of some
`const_cast`s.

Add MutableSymbolRef and MutableSymbolVector as mutable analogs to
SymbolRef and SymbolVector. Replace uses of equivalent types with those
names.

Differential Revision: https://reviews.llvm.org/D79346
2020-05-06 12:22:28 -07:00
Pete Steinfeld 8d0c3c05f2 [flang] New implementation for checks for constraints C741 through C750
Summary:
Most of these checks were already implemented, and I just added references to
them to the code and tests. Also, much of this code was already
reviewed in the old flang/f18 GitHub repository, but I didn't get to
merge it before we switched repositories.

I implemented the check for C747 to not allow coarray components in derived
types that are of type C_PTR, C_FUNPTR, or type TEAM_TYPE.

I implemented the check for C748 that requires a data component whose type has
a coarray ultimate component to be a nonpointer, nonallocatable scalar and not
be a coarray.

I implemented the check for C750 that adds additional restrictions to the
bounds expressions of a derived type component that's an array.
These bounds expressions are sepcification expressions as defined in
10.1.11.  There was already code in lib/Evaluate/check-expression.cpp to
check semantics for specification expressions, but it did not check for
the extra requirements of C750.

C750 prohibits specification functions, the intrinsic functions
ALLOCATED, ASSOCIATED, EXTENDS_TYPE_OF, PRESENT, and SAME_TYPE_AS. It
also requires every specification inquiry reference to be a constant
expression, and requires that the value of the bound not depend on the
value of a variable.

To implement these additional checks, I added code to the intrinsic proc
table to get the intrinsic class of a procedure.  I also added an
enumeration to distinguish between specification expressions for
derived type component bounds versus for type parameters.  I then
changed the code to pass an enumeration value to
"CheckSpecificationExpr()" to indicate that the expression was a bounds
expression and used this value to determine whether to emit an error
message when violations of C750 are found.

I changed the implementation of IsPureProcedure() to handle statement
functions and changed some references in the code that tested for the
PURE attribute to call IsPureProcedure().

I also fixed some unrelated tests that got new errors when I implemented these
new checks.

Reviewers: tskeith, DavidTruby, sscalpone

Subscribers: jfb, llvm-commits

Tags: #llvm, #flang

Differential Revision: https://reviews.llvm.org/D79263
2020-05-05 09:37:39 -07:00
David Truby 75c31057a7 [flang] Semantic checks for OpenMP combined constructs.
Summary:
This includes a refactor of the existing combined construct checks
that were present, as well as adding the remaining combined constructs
that had not been implemented yet.

Reviewers: jdoerfert

Subscribers: yaxunl, guansong, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D77812
2020-04-27 12:40:49 +01:00
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
peter klausler 455ed8de4f [flang] Process names in ASSIGN and assigned GOTO
Allow ASSIGNed integer variables as formats

Address review comment

Original-commit: flang-compiler/f18@361a151508
Reviewed-on: https://github.com/flang-compiler/f18/pull/1099
2020-04-03 14:58:07 -07:00
Pete Steinfeld 2b790490b6 [flang] Checks for constraints C731 through C740
In most cases, I just added the contraint names to the code and tests.

I implemented the following checks:
  - C736 A child type with a coarray ultimate component must have a parent with
    a coarray ultimate component.
  - C737 A child type with and EVENT_TYPE or LOCK_TYPE component must have a
    parent either which is EVENT_TYPE or LOCK_TYPE or a type with an EVENT_TYPE
    or LOCK_TYPE component.
  - C740 Sequence types must contain at least on component
  - C740 Data components of sequence types must either be of an intrinsic type
    or a sequenced derived type.

After implementing these checks, some tests had new errors unrelated to their
original purpose, so I fixed them.

Original-commit: flang-compiler/f18@098f01bc47
Reviewed-on: https://github.com/flang-compiler/f18/pull/1097
2020-04-02 06:41:33 -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 c42f6314eb [flang] Semantics for ENTRY
initial test passes

Move some checks to check-declarations

Fix bugs found in testing

Get tests all passing

Allow declaration statements for function result to follow ENTRY

Fix another bug

Original-commit: flang-compiler/f18@e82cfee432
Reviewed-on: https://github.com/flang-compiler/f18/pull/1086
2020-03-24 14:30:34 -07:00
Pete Steinfeld e17e71735e [flang] Changes to enforce constraints C727 to C730 and most constraints related to attributes
The full list of constraints is C727, C728, C729, C730, C743, C755, C759, C778,
and C1543.

I added a function to tools.cpp to check to see if a symbol name is the name
of an intrinsic type.

The biggest change was to resolve-names.cpp to check to see if attributes were
either duplicated or in conflict with each other.  I changed all locations
where attributes were set to check for duplicates or conflicts.

I also added tests for all checks and annotated the tests and code with the
numbers of the constraints being tested/checked.

Original-commit: flang-compiler/f18@3f30e8a61e
Reviewed-on: https://github.com/flang-compiler/f18/pull/1084
2020-03-24 09:24:49 -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 9977b24a6d [flang] Improve error message for procedure passed as invalid argument to an intrinsic
Support forward references to sibling module procedures

Add tests, handle corner cases

Rename new test

Original-commit: flang-compiler/f18@234bb519cd
Reviewed-on: https://github.com/flang-compiler/f18/pull/1076
2020-03-18 14:04:08 -07:00
Tim Keith 824d198e31 [flang] Create symbols for args of separate-module-subprogram
A separate-module-subprogram is declared as `module procedure ...`
and gets its characteristics from the declaration of that name as
a separate module procedure. When we encounter one, we need to create
symbols in the new subprogram scope for the dummy arguments and
function return (if any).

The failure to create these symbols led to the bug in issue flang-compiler/f18#1054:
when a dummy argument was referenced, the compiler interpreted it as
an implicit declaration because there was no symbol for the argument.

Fixes flang-compiler/f18#1054.

Original-commit: flang-compiler/f18@4d3c4bac84
Reviewed-on: https://github.com/flang-compiler/f18/pull/1080
Tree-same-pre-rewrite: false
2020-03-17 16:01:59 -07:00
Tim Keith d1ce4d275f [flang] Fix location of name of Symbol for ProcEntity
When we encounter a ProcDecl and a symbol for it has already been
created, replace the CharBlock for the name with the one in the ProcDecl
as it is the "main" declaration of that name. This matches what is done
for an EntityDecl.

This moves the location of some error messages to a better source
location so update the affected tests.

Original-commit: flang-compiler/f18@514c0f2c94
Reviewed-on: https://github.com/flang-compiler/f18/pull/1080
Tree-same-pre-rewrite: false
2020-03-17 16:01:59 -07:00
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
Tim Keith 47452b9691 [flang] Improve checking of structure constructor arguments
When a misparsed FunctionReference was converted to a StructureConstructor,
the components accessed were not checked for accessibility.

The conversion happens in expression analysis so that where the accessibity
must be checked. So move `CheckAccessibleComponent` to `tools.h` so that it
can be shared by `resolve-names.cpp` and `expression.cpp`.

Add FindModuleContaining to help implement this and use it other places.

Check that an access-spec can only appear in a module.

Remove some unnecessary "semantics::" qualifiers.

Original-commit: flang-compiler/f18@99ce156e49
Reviewed-on: https://github.com/flang-compiler/f18/pull/1046
2020-03-03 13:24:09 -08:00
Pete Steinfeld 84b2909ded [flang] Responses to pull request comments
I cleaned up some code and reverted a change to semantic checking for
the exponent letter in REAL literals.

Original-commit: flang-compiler/f18@e81f57fcf5
Reviewed-on: https://github.com/flang-compiler/f18/pull/1031
2020-02-27 08:49:40 -08:00
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
Tim Keith 914a91c1c3 [flang] Fix misparsed structure constructor in data stmt
In a data statement like `data x / a(1) /`, `a(1)` may be an array
element or a structure constructor. It is parsed as an array element
so if it turns out `a` is a derived type it must be rewritten as a
strucutre constructor.

Original-commit: flang-compiler/f18@a2b2a330e7
Reviewed-on: https://github.com/flang-compiler/f18/pull/1024
2020-02-25 17:13:56 -08:00
Tim Keith de066a2756 [flang] Allow for access-stmt before namelist-stmt
You can declare a name in an access statement and then declare it as
a namelist group name. We weren't allowing that because we didn't
convert a symbol with UnknownDetails to one with NamelistDetails.

Fixes flang-compiler/f18#1022.

Original-commit: flang-compiler/f18@a759204db5
Reviewed-on: https://github.com/flang-compiler/f18/pull/1023
2020-02-25 15:22:13 -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