This patch implements Clang support for an original OpenMP extension
we have developed to support OpenACC: the `ompx_hold` map type
modifier. The next patch in this series, D106510, implements OpenMP
runtime support.
Consider the following example:
```
#pragma omp target data map(ompx_hold, tofrom: x) // holds onto mapping of x
{
foo(); // might have map(delete: x)
#pragma omp target map(present, alloc: x) // x is guaranteed to be present
printf("%d\n", x);
}
```
The `ompx_hold` map type modifier above specifies that the `target
data` directive holds onto the mapping for `x` throughout the
associated region regardless of any `target exit data` directives
executed during the call to `foo`. Thus, the presence assertion for
`x` at the enclosed `target` construct cannot fail. (As usual, the
standard OpenMP reference count for `x` must also reach zero before
the data is unmapped.)
Justification for inclusion in Clang and LLVM's OpenMP runtime:
* The `ompx_hold` modifier supports OpenACC functionality (structured
reference count) that cannot be achieved in standard OpenMP, as of
5.1.
* The runtime implementation for `ompx_hold` (next patch) will thus be
used by Flang's OpenACC support.
* The Clang implementation for `ompx_hold` (this patch) as well as the
runtime implementation are required for the Clang OpenACC support
being developed as part of the ECP Clacc project, which translates
OpenACC to OpenMP at the directive AST level. These patches are the
first step in upstreaming OpenACC functionality from Clacc.
* The Clang implementation for `ompx_hold` is also used by the tests
in the runtime implementation. That syntactic support makes the
tests more readable than low-level runtime calls can. Moreover,
upstream Flang and Clang do not yet support OpenACC syntax
sufficiently for writing the tests.
* More generally, the Clang implementation enables a clean separation
of concerns between OpenACC and OpenMP development in LLVM. That
is, LLVM's OpenMP developers can discuss, modify, and debug LLVM's
extended OpenMP implementation and test suite without directly
considering OpenACC's language and execution model, which can be
handled by LLVM's OpenACC developers.
* OpenMP users might find the `ompx_hold` modifier useful, as in the
above example.
See new documentation introduced by this patch in `openmp/docs` for
more detail on the functionality of this extension and its
relationship with OpenACC. For example, it explains how the runtime
must support two reference counts, as specified by OpenACC.
Clang recognizes `ompx_hold` unless `-fno-openmp-extensions`, a new
command-line option introduced by this patch, is specified.
Reviewed By: ABataev, jdoerfert, protze.joachim, grokos
Differential Revision: https://reviews.llvm.org/D106509
where should not.
Currently we are using QTy->isIncompleteType(&ND) to check incomplete
type. But before doing that, need to instantiate for a class template
specialization or a class member of a class template specialization,
or an array with known size of such..., so that we know it is really
incomplete type.
To fix this using RequireCompleteType instead.
The new test is added into "test/OpenMP/target_update_messages.cpp"
The different of using RequireCompleteType is when emit incomplete type,
an additional note is also emitted to point to where incomplete type
is declared. Because this change, many tests are needed to be fixed
by adding additional note.
This is to fix https://bugs.llvm.org/show_bug.cgi?id=50508
Differential Revision: https://reviews.llvm.org/D107200
OpenMP 5.0 removed a lot of restriction for overlapped mapped items
comparing to OpenMP 4.5. Patch restricts the checks for overlapped data
mappings only for OpenMP 4.5 and less and reorders mapping of the
arguments so, that present and alloc mappings are processed first and
then all others.
Differential Revision: https://reviews.llvm.org/D86119
This patch implements Clang front end support for the OpenMP TR8
`present` map type modifier. The next patch in this series implements
OpenMP runtime support.
This patch does not attempt to implement TR8 sec. 2.22.7.1 "map
Clause", p. 319, L14-16:
> If a map clause with a present map-type-modifier is present in a map
> clause, then the effect of the clause is ordered before all other
> map clauses that do not have the present modifier.
Compare to L10-11, which Clang does not appear to implement yet:
> For a given construct, the effect of a map clause with the to, from,
> or tofrom map-type is ordered before the effect of a map clause with
> the alloc, release, or delete map-type.
This patch also does not implement the `present` implicit-behavior for
`defaultmap` or the `present` motion-modifier for `target update`.
Reviewed By: ABataev
Differential Revision: https://reviews.llvm.org/D83061
Summary:
When -fopenmp option is specified then version 5.0 will be set as
default.
Reviewers: gregrodgers, jdoerfert, ABataev
Reviewed By: ABataev
Subscribers: pdhaliwal, yaxunl, guansong, sstefan1, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D81098
Summary:
Added basic analysis of map clauses. Only map clauses with to and tofrom
map type must be analyzed since all other map types (alloc, delete, etc.) do not require to use the value of the initial variable, instead they create the new copy of the variable.
Reviewers: NoQ
Subscribers: guansong, cfe-commits, kkwli0, caomhin
Tags: #clang
Differential Revision: https://reviews.llvm.org/D66668
llvm-svn: 370214
Without this patch, APSInt inherits APInt::isNegative, which merely
checks the sign bit without regard to whether the type is actually
signed. isNonNegative and isStrictlyPositive call isNegative and so
are also affected.
This patch adjusts APSInt to override isNegative, isNonNegative, and
isStrictlyPositive with implementations that consider whether the type
is signed.
A large set of Clang OpenMP tests are affected. Without this patch,
these tests assume that `true` is not a valid argument for clauses
like `collapse`. Indeed, `true` fails APInt::isStrictlyPositive but
not APSInt::isStrictlyPositive. This patch adjusts those tests to
assume `true` should be accepted.
This patch also adds tests revealing various other similar fixes due
to APSInt::isNegative calls in Clang's ExprConstant.cpp and
SemaExpr.cpp: `++` and `--` overflow in `constexpr`, evaluated object
size based on `alloc_size`, `<<` and `>>` shift count validation, and
OpenMP array section validation.
Reviewed By: lebedev.ri, ABataev, hfinkel
Differential Revision: https://reviews.llvm.org/D59712
llvm-svn: 359012
This patch implements the parsing and sema support for OpenMP map
clauses with potential user-defined mapper attached. User defined mapper
is a new feature in OpenMP 5.0. A map clause can have an explicit or
implicit associated mapper, which instructs the compiler to generate
extra data mapping. An example is shown below:
struct S { int len; int *d; };
#pragma omp declare mapper(id: struct S s) map(s, s.d[0:s.len])
struct S ss;
#pragma omp target map(mapper(id) tofrom: ss) // use the mapper with name 'id' to map ss
Contributed-by: Lingda Li <lildmh@gmail.com>
Differential Revision: https://reviews.llvm.org/D58074
llvm-svn: 354347
A map clause with the close map-type-modifier is a hint to
prefer that the variables are mapped using a copy into faster
memory.
Patch by Ahsan Saghir (saghir)
Differential Revision: https://reviews.llvm.org/D55719
llvm-svn: 349551
only.
Added support for -fopenmp-simd option that allows compilation of
simd-based constructs without emission of OpenMP runtime calls.
llvm-svn: 321560
This patch is to implement sema and parsing for 'target teams distribute' pragma.
Differential Revision: https://reviews.llvm.org/D28015
llvm-svn: 290508
Joel E. Denny