When an array's shape involves references to symbols that are not
invariant in a scope -- the classic example being a dummy array
with an explicit shape involving other dummy arguments -- the
compiler was creating shape expressions that referenced those
symbols. This might be valid if those symbols are somehow
captured and copied at each entry point to a subprogram, and
the copies referenced in the shapes instead, but that's not
the case.
This patch introduces a new expression predicate IsScopeInvariantExpr(),
which defines a class of expressions that contains constant expressions
(in the sense that the standard uses that term) as well as references
to items that may be safely accessed in a context-free way throughout
their scopes. This includes dummy arguments that are INTENT(IN)
and not VALUE, descriptor inquiries into descriptors that cannot
change, and bare LEN type parameters within the definitions of
derived types. The new predicate is then used in shape analysis
to winnow out results that would have otherwise been contextual.
Differential Revision: https://reviews.llvm.org/D113309
Use derived type information tables to drive default component
initialization (when needed), component destruction, and calls to
final subroutines. Perform these operations automatically for
ALLOCATE()/DEALLOCATE() APIs for allocatables, automatics, and
pointers. Add APIs for use in lowering to perform these operations
for non-allocatable/automatic non-pointer variables.
Data pointer component initialization supports arbitrary constant
designators, a F'2008 feature, which may be a first for Fortran
implementations.
Differential Revision: https://reviews.llvm.org/D106297
Add the following options:
* -fdebug-dump-symbols
* -fdebug-dump-parse-tree
* -fdebug-dump-provenance
Summary of changes:
- Add 3 new frontend actions: DebugDumpSymbolsAction, DebugDumpParseTreeAction and DebugDumpProvenanceAction
- Add a unique pointer to the Semantics instance created in PrescanAndSemaAction
- Move fatal semantic error reporting to its own method, FrontendActions#reportFatalSemanticErrors
- Port most tests using `-fdebug-dump-symbols` and `-fdebug-dump-parse-tree` to the new driver if built, otherwise default to f18
Differential Revision: https://reviews.llvm.org/D96716
The following _action_ options are always used with `-fsyntax-only`
(also an _action_ option):
* -fdebug-dump-symbols
* -fdebug-dump-parse-tree
This patch makes the above options imply `-fsyntax-only`.
From the perspective of `f18` this change saves typing and is otherwise
a non-functional change. But it will simplify things in the new driver,
`flang-new`, in which only the last action option is taken into account
and executed. In other words, the following would only run
`-fsyntax-only`:
```
flang-new -fdebug-dump-symbols -fsyntax-only <input>
```
whereas this would only run `-fdebug-dump-symbols`:
```
flang-new -fsyntax-only -fdebug-dump-symbols <input>
```
Differential Revision: https://reviews.llvm.org/D96528
Now that semantics is working, the standard -fsyntax-only option of
GNU and Clang should be used as the name of the option that causes
f18 to just run the front-end. Support both options in f18, silently
accepting the old option as a synonym for the new one (as
preferred by the code owner), and replace all instances of the
old -fparse-only option with -fsyntax-only throughout the source base.
Differential Revision: https://reviews.llvm.org/D95887
IsDescriptor was returning false for a component whose shape depended
on a length parameter. Change it to return true for any array with
non-constant bounds.
Differential Revision: https://reviews.llvm.org/D79349
Summary:
Add size and offset properties to symbols, representing their byte size
and offset within their enclosing scope.
Add size and align properties to scopes so that they are available for
scopes representing derived types.
Add ComputeOffsets pass over the symbol table to fill in those fields.
Compute descriptor size based on rank and length parameters. Extract
DerivedTypeSpec::NumLengthParameters from DynamicType::RequiresDescriptor
to share the code.
Add Scope::GetSymbols to get symbols in canonical order.
compute-offsets.cpp and mod-file.cpp both need to process symbols in the
order in which they are declared. Move the collecting of those symbols
into Scope so that it can be shared.
Add symbol size and offset to output of `-fdebug-dump-symbols` and use
that in some tests.
Still to do:
- make size and alignment rules configurable based on target
- use offsets to check EQUIVALENCE statements
Differential Revision: https://reviews.llvm.org/D78680
