Andrezj W. @ Arm discovered that the runtime derived type table
building code in semantics was detecting fatal errors in the tests
that the f18 driver wasn't printing. This patch fixes f18 so that
these messages are printed; however, the messages were not valid user
errors, and the rest of this patch fixes them up.
There were two sources of the bogus errors. One was that the runtime
derived type information table builder was calculating the shapes of
allocatable and pointer array components in derived types, and then
complaining that they weren't constant or LEN parameter values, which
of course they couldn't be since they have to have deferred shapes
and those bounds were expressions like LBOUND(component,dim=1).
The second was that f18 was forwarding the actual LEN type parameter
expressions of a type instantiation too far into the uses of those
parameters in various expressions in the declarations of components;
when an actual LEN type parameter is not a constant value, it needs
to remain a "bare" type parameter inquiry so that it will be lowered
to a descriptor inquiry and acquire a captured expression value.
Fixing this up properly involved: moving some code into new utility
function templates in Evaluate/tools.h, tweaking the rewriting of
conversions in expression folding to elide needless integer kind
conversions of type parameter inquiries, making type parameter
inquiry folding *not* replace bare LEN type parameters with
non-constant actual parameter values, and cleaning up some
altered test results.
Differential Revision: https://reviews.llvm.org/D101001
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
F18 supports the standard intrinsic function SELECTED_REAL_KIND
but not its synonym in the standard module IEEE_ARITHMETIC
named IEEE_SELECTED_REAL_KIND until this patch.
Differential Revision: https://reviews.llvm.org/D100066
We were not folding type parameter inquiries for the form 'var%typeParam'
where 'typeParam' was a KIND or LEN type parameter of a derived type and 'var'
was a designator of the derived type. I fixed this by adding code to the
function 'FoldOperation()' for 'TypeParamInquiry's to handle this case. I also
cleaned up the code for the case where there is no designator.
In order to make the error messages correctly refer to both the points of
declaration and instantiation, I needed to add an argument to the function
'InstantiateIntrinsicType()' for the location of the instantiation.
I also changed the formatting of 'TypeParamInquiry' to correctly format this
case. I also added tests for both KIND and LEN type parameter inquiries in
resolve104.f90.
Making these changes revealed an error in resolve89.f90 and caused one of the
error messages in assign04.f90 to be different.
Reviewed By: klausler
Differential Revision: https://reviews.llvm.org/D99892
We were not folding type parameter inquiries for the form 'var%typeParam'
where 'typeParam' was a KIND or LEN type parameter of a derived type and 'var'
was a designator of the derived type. I fixed this by adding code to the
function 'FoldOperation()' for 'TypeParamInquiry's to handle this case. I also
cleaned up the code for the case where there is no designator.
In order to make the error messages correctly refer to both the points of
declaration and instantiation, I needed to add an argument to the function
'InstantiateIntrinsicType()' for the location of the instantiation.
I also changed the formatting of 'TypeParamInquiry' to correctly format this
case. I also added tests for both KIND and LEN type parameter inquiries in
resolve104.f90.
Making these changes revealed an error in resolve89.f90 and caused one of the
error messages in assign04.f90 to be different.
Differential Revision: https://reviews.llvm.org/D99892
f18 was emitting a bogus error message about the lack of a TARGET
attribute when a pointer was initialized with a component of a
variable that was a legitimate TARGET.
Differential Revision: https://reviews.llvm.org/D99665
Folding of LOGICAL intrinsic procedure was missing in the front-end causing
crash when using it in parameter expressions.
Simply fold LOGICAL calls to evaluate::Convert<T>.
Differential Revision: https://reviews.llvm.org/D99346
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
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
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
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
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
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.
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
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
It's possible to define a procedure that has a procedure dummy argument which
names the procedure that contains it. This was causing the compiler to fall
into an infinite loop when characterizing a call to the procedure.
Following a suggestion from Peter, I fixed this be maintaining a set of
procedure symbols that had already been seen while characterizing a procedure.
This required passing a new parameter to the functions that characterized a
Procedure, a DummyArgument, and a DummyProcedure.
I also added several tests that will crash the compiler without this change.
Differential Revision: https://reviews.llvm.org/D96631
Constant folding for calls to LBOUND() was not working when the lower bound of
a constant array was not 1.
I fixed this and re-enabled the test in Evaluate/folding16.f90 that previously
was silently failing. I slightly changed the test to parenthesize the first
argument to exercise all of the new code.
Differential Revision: https://reviews.llvm.org/D95894
Split up MeasureSizeInBytes() so that array element sizes can be
calculated accurately; use the new API in some places where
DynamicType::MeasureSizeInBytes() was being used but the new
API performs better due to TypeAndShape having precise CHARACTER
length information.
Differential Revision: https://reviews.llvm.org/D95897
Implement IEEE_SUPPORT_DATATYPE() and other inquiry intrinisic
functions from the intrinsic module IEEE_ARITHMETIC, folding all of
their results to .TRUE.
Differential Revision: https://reviews.llvm.org/D95830
Analyze the shape of the result of TRANSFER(ptr,array) correctly
when "ptr" is an array of deferred shape. Fixing this bug led to
some refactoring and concentration of common code in TypeAndShape
member functions with code in general shape and character length
analysis, and this led to some regression test failures that have
all been cleaned up.
Differential Revision: https://reviews.llvm.org/D95744
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
There were two problems with constant arrays whose lower bound is not 1.
First, when folding the arrays, we were creating the folded array to have lower
bounds of 1 but, we were not re-adjusting their lower bounds to the
declared values. Second, we were not calculating the extents correctly.
Both of these problems led to bogus error messages.
I fixed the first problem by adjusting the lower bounds in
NonPointerInitializationExpr() in Evaluate/check-expression.cpp. I wrote the
class ArrayConstantBoundChanger, which is similar to the existing class
ScalarConstantExpander. In the process of implementing and testing it, I found
a bug that I fixed in ScalarConstantExpander which caused it to infinitely
recurse on parenthesized expressions. I also removed the unrelated class
ScalarExpansionVisitor, which was not used.
I fixed the second problem by changing the formula that calculates upper bounds
in in the function ComputeUpperBound() in Evaluate/shape.cpp.
I added tests that trigger the bogus error messages mentioned above along with
a constant folding tests that uses array operands with shapes that conform but
have different bounds.
In the process of adding tests, I discovered that tests in
Evaluate/folding09.f90 and folding16.f90 were written incorrectly, and I
fixed them. This also revealed a bug in contant folding of the
intrinsic "lbounds" which I plan to fix in a later change.
Differential Revision: https://reviews.llvm.org/D95449
Correct the analysis of references to transformational intrinsic
functions that have different semantics based on the presence or
absence of a DIM= argument; add shape analysis for UNPACK().
Differential Revision: https://reviews.llvm.org/D94716
Expressions emitted to module files and error messages
sometimes contain conversions of integer results of inquiry
intrinsics; these are usually not needed, and can conflict
with "int" in the user's namespace. Improve folding so that
these conversions don't appear, and do some other clean-up
in adjacent code.
Differential Revision: https://reviews.llvm.org/D95172
* 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
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
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
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
Internal subprograms have explicit interfaces. If an internal subprogram has
an alternate return, we check its explicit interface. But we were not
putting the label values of alternate returns into the actual argument.
I fixed this by changing the definition of actual arguments to be able
to contain a common::Label and putting the label for an alternate return
into the actual argument.
I also verified that we were already doing all of the semantic checking
required for alternate returns and removed a "TODO" for this.
I also added the test altreturn06.f90.
Differential Revision: https://reviews.llvm.org/D94017
Elemental intrinsic function folding was not taking the lower
bounds of constant array arguments into account; these lower bounds
can be distinct from 1 when named constants appear as arguments.
LLVM bugzilla #48437.
Differential Revision: https://reviews.llvm.org/D93321
STORAGE_SIZE() is a standard inquiry intrinsic (size in bits
of an array element of the same type as the argument); SIZEOF()
is a common extension that returns the size in bytes of its
argument; C_SIZEOF() is a renaming of SIZEOF() in module ISO_C_BINDING.
STORAGE_SIZE() and SIZEOF() are implemented via rewrites to
expressions; these expressions will be constant when the necessary
type parameters and bounds are also constant.
Code to calculate the sizes of types (with and without alignment)
was isolated into Evaluate/type.* and /characteristics.*.
Code in Semantics/compute-offsets.* to calculate sizes and alignments
of derived types' scopes was exposed so that it can be called at type
instantiation time (earlier than before) so that these inquiry intrinsics
could be called from specification expressions.
Differential Revision: https://reviews.llvm.org/D93322
Remove resolved & moot TODO comments in Common/, Parser/,
and Evaluate/. Address a pending one relating to parsing
ambiguity in DATA statement constants, handling it with
symbol table information in Semantics and adding a test.
Differential Revision: https://reviews.llvm.org/D93323
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
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
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
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
When comparing arrays whose shapes do not conform, the contant folding
code ran into problems trying to get the value of an extent that did not
exist. There were actually two problems. First, the routine
"CheckConformance()" was returning "true" when the compiler was unable
to get the extent of an array. Second, the function
"ApplyElementwise()" was calling "CheckConformance()" prior to folding
the elements of two arrays, but it was ignoring the return value.
Differential Revision: https://reviews.llvm.org/D91440
Avoid a spurious error message about a dummy procedure reference
in a specification expression by restructuring the handling of
use-associated and host-associated symbols.
Updated to fix a circular dependence between shared library
binaries that was introduced by the original patch.
Differential revision: https://reviews.llvm.org/D91286
Avoid a spurious error message about a dummy procedure reference
in a specification expression by restructuring the handling of
use-associated and host-associated symbols.
Differential revision: https://reviews.llvm.org/D91209
Add explicit member initializers to the declarations of
some constexpr values added in a recent patch to avoid an
apparent problem with gcc 8.2.0 with default initializers.
Differential revision: https://reviews.llvm.org/D90696
Ensure that character length is properly calculated for
actual arguments to intrinsics, and that source provenance
information is available when expression analysis calls
folding in cases where the length is invalid.
Differential revision: https://reviews.llvm.org/D90636
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
peter klausler