Commit Graph

7 Commits

Author SHA1 Message Date
Peter Klausler c4f67ea12e [flang] Allow DATA initialization of derived types w/ allocatable components
While one cannot of course statically initialize an allocatable component
of an instance of a derived type, its mere presence should not prevent
DATA initialization of the other nonallocatable components.  Semantics
was treating the existence of an allocatable component as a case of
"default initialization", which it is, but not one that should run
afoul of C877.  Add another Boolean argument to IsInitialized() to allow
for a more nuanced test.

Differential Revision: https://reviews.llvm.org/D119449
2022-02-14 10:43:49 -08:00
peter klausler d60a02201d [flang] Include default component initialization in static initializers
The combined initializers constructed from DATA statements and explicit
static initialization in declarations needs to include derived type
component default initializations, overriding those default values
without complaint with values from explicit DATA statement or declaration
initializations when they overlap.  This also has to work for objects
with storage association due to EQUIVALENCE.  When storage association causes
default component initializations to overlap, emit errors if and only
if the values differ (See Fortran 2018 subclause 19.5.3, esp. paragraph
10).

The f18 front-end has a module that analyzes and converts DATA statements
into equivalent static initializers for objects.  For storage-associated
objects, compiler-generated objects are created that overlay the entire
association and fill it with a combined initializer.  This "data-to-inits"
module already exists, and this patch is essentially extension and
clean-up of its machinery to complete the job.

Also: emit EQUIVALENCE to module files; mark compiler-created symbols
and *don't* emit those to module files; check non-static EQUIVALENCE
sets for conflicting default component initializations, so lowering
doesn't have to check them or emit diagnostics.

Differential Revision: https://reviews.llvm.org/D109022
2021-09-01 09:40:37 -07:00
peter klausler 6aa3591e98 [flang] Implement STORAGE_SIZE(), SIZEOF(), C_SIZEOF()
STORAGE_SIZE() is a standard inquiry intrinsic (size in bits
of an array element of the same type as the argument); SIZEOF()
is a common extension that returns the size in bytes of its
argument; C_SIZEOF() is a renaming of SIZEOF() in module ISO_C_BINDING.

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

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

Differential Revision: https://reviews.llvm.org/D93322
2020-12-15 17:26:20 -08:00
peter klausler fad31d6032 [flang] Implement shape analysis of TRANSFER intrinsic function result
The shape (esp. the size) of the result of a call to TRANSFER
is implemented according to the definition in the standard.

Differential Revision: https://reviews.llvm.org/D85866
2020-08-13 09:56:24 -07:00
peter klausler 4ac617f490 [flang] Handle DATA initialization of EQUIVALENCE'd objects
Objects that are storage associated by EQUIVALENCE and
initialized with DATA are initialized by creating a
compiler temporary data object in the same scope,
assigning it an offset, type, and size that covers the
transitive closure of the associated initialized original
symbols, and combining their initializers into one common
initializer for the temporary.

Some problems with offset assignment of EQUIVALENCE'd objects
in COMMON were exposed and corrected, and some more error
cases are checked.

Remove obsolete function.
Small bugfix (nested implied dos).
Add a test.
Fix struct/class warning.

Differential Revision: https://reviews.llvm.org/D85560
2020-08-07 16:39:23 -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 286d7a2159 [flang] DATA statement processing (part 2/4): Initial images
Summary:
Defines a representation for the initialized memory image of
a variable.  This image is populated by DATA statement
processing as designator elements are put into correspondence
with values, then converted into an initializer in the symbol
table so that lowering can pass the initial image to the
code generator.

Reviewers: tskeith, PeteSteinfeld, sscalpone, jdoerfert, DavidTruby

Reviewed By: tskeith

Subscribers: mgorny, llvm-commits, flang-commits

Tags: #flang, #llvm

Differential Revision: https://reviews.llvm.org/D82131
2020-06-18 17:13:59 -07:00