This is the first part extracted from D71179 and cleaned up.
This patch provides parsing support for `omp begin/end declare variant`,
as defined in OpenMP technical report 8 (TR8) [0].
A major purpose of this patch is to provide proper math.h/cmath support
for OpenMP target offloading. See PR42061, PR42798, PR42799. The current
code was developed with this feature in mind, see [1].
[0] https://www.openmp.org/wp-content/uploads/openmp-TR8.pdf
[1] https://reviews.llvm.org/D61399#change-496lQkg0mhRN
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D74941
If the ancestor device modifier is used and the value of the device
clause is evaluated to 1, the ancestor device shall be used for the
execution.
Since the reverse offloading is not supported yet, the target construct
execution is always initiated from the host, not from the device. So, if
the ancestor modifier is specified, just execute target region on the
host.
Avoid copying of the orignal variable if it is going to be marked as
firstprivate in task regions. For taskloops, still need to copy the
non-trvially copyable variables to correctly construct them upon task
creation.
Most clients of SourceManager.h need to do things like turning source
locations into file & line number pairs, but this doesn't require
bringing in FileManager.h and LLVM's FS headers.
The main code change here is to sink SM::createFileID into the cpp file.
I reason that this is not performance critical because it doesn't happen
on the diagnostic path, it happens along the paths of macro expansion
(could be hot) and new includes (less hot).
Saves some includes:
309 - /usr/local/google/home/rnk/llvm-project/clang/include/clang/Basic/FileManager.h
272 - /usr/local/google/home/rnk/llvm-project/clang/include/clang/Basic/FileSystemOptions.h
271 - /usr/local/google/home/rnk/llvm-project/llvm/include/llvm/Support/VirtualFileSystem.h
267 - /usr/local/google/home/rnk/llvm-project/llvm/include/llvm/Support/FileSystem.h
266 - /usr/local/google/home/rnk/llvm-project/llvm/include/llvm/Support/Chrono.h
Differential Revision: https://reviews.llvm.org/D75406
Added codegen for update clause in depobj. Reads the number of the
elements from the first element and updates flags for each element in
the loop.
```
omp_depend_t x;
kmp_depend_info *base = (kmp_depend_info *)x;
intptr_t num = x[-1].base_addr;
kmp_depend_info *end = x + num;
kmp_depend_info *el = base;
do {
el.flags = new_flag;
el = &el[1];
} while (el != end);
```
in depobj object.
The first element in the list of the dependencies is used for internal
purposes to store the number of the elements in the provided list.
The first element now is skipped and depobj object poits exactly to the
list of dependencies.
Added codegen for 'depend' clause in depobj directive. The depend clause
is emitted as kmp_depend_info <deps>[<number_of_items_in_clause> + 1]. The
first element in this array is reserved for storing the number of
elements in this array: <deps>[0].base_addr =
<number_of_items_in_clause>;
This extra element is required to implement 'update' and 'destroy'
clauses. It is required to know the size of array to destroy it
correctly and to update depency kind.
Chen
Summary:
Base declaration in pointer arithmetic expression is determined by
binary search with type information. Take "int *a, *b; *(a+*b)" as an
example, we determine the base by checking the type of LHS and RHS. In
this case the type of LHS is "int *", the type of RHS is "int",
therefore, we know that we need to visit LHS in order to find base
declaration.
Reviewers: ABataev, jdoerfert
Reviewed By: ABataev
Subscribers: guansong, cfe-commits, sandoval, dreachem
Tags: #clang
Differential Revision: https://reviews.llvm.org/D75077
This patch implements an almost complete handling of OpenMP
contexts/traits such that we can reuse most of the logic in Flang
through the OMPContext.{h,cpp} in llvm/Frontend/OpenMP.
All but construct SIMD specifiers, e.g., inbranch, and the device ISA
selector are define in `llvm/lib/Frontend/OpenMP/OMPKinds.def`. From
these definitions we generate the enum classes `TraitSet`,
`TraitSelector`, and `TraitProperty` as well as conversion and helper
functions in `llvm/lib/Frontend/OpenMP/OMPContext.{h,cpp}`.
The above enum classes are used in the parser, sema, and the AST
attribute. The latter is not a collection of multiple primitive variant
arguments that contain encodings via numbers and strings but instead a
tree that mirrors the `match` clause (see `struct OpenMPTraitInfo`).
The changes to the parser make it more forgiving when wrong syntax is
read and they also resulted in more specialized diagnostics. The tests
are updated and the core issues are detected as before. Here and
elsewhere this patch tries to be generic, thus we do not distinguish
what selector set, selector, or property is parsed except if they do
behave exceptionally, as for example `user={condition(EXPR)}` does.
The sema logic changed in two ways: First, the OMPDeclareVariantAttr
representation changed, as mentioned above, and the sema was adjusted to
work with the new `OpenMPTraitInfo`. Second, the matching and scoring
logic moved into `OMPContext.{h,cpp}`. It is implemented on a flat
representation of the `match` clause that is not tied to clang.
`OpenMPTraitInfo` provides a method to generate this flat structure (see
`struct VariantMatchInfo`) by computing integer score values and boolean
user conditions from the `clang::Expr` we keep for them.
The OpenMP context is now an explicit object (see `struct OMPContext`).
This is in anticipation of construct traits that need to be tracked. The
OpenMP context, as well as the `VariantMatchInfo`, are basically made up
of a set of active or respectively required traits, e.g., 'host', and an
ordered container of constructs which allows duplication. Matching and
scoring is kept as generic as possible to allow easy extension in the
future.
---
Test changes:
The messages checked in `OpenMP/declare_variant_messages.{c,cpp}` have
been auto generated to match the new warnings and notes of the parser.
The "subset" checks were reversed causing the wrong version to be
picked. The tests have been adjusted to correct this.
We do not print scores if the user did not provide one.
We print spaces to make lists in the `match` clause more legible.
Reviewers: kiranchandramohan, ABataev, RaviNarayanaswamy, gtbercea, grokos, sdmitriev, JonChesterfield, hfinkel, fghanim
Subscribers: merge_guards_bot, rampitec, mgorny, hiraditya, aheejin, fedor.sergeev, simoncook, bollu, guansong, dexonsmith, jfb, s.egerton, llvm-commits, cfe-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D71830
The code generation is exactly the same as it was.
But not that the special handling of untied tasks is still handled by
emitUntiedSwitch in clang.
Differential Revision: https://reviews.llvm.org/D69828
According to OpenMP 5.0, cancel and cancellation point constructs are
supported in taskloop directive. Added support for cancellation in
taskloop, master taskloop and parallel master taskloop.
directive.
According to OpenMP 5.0, The atomic_default_mem_order clause specifies the default memory ordering behavior for atomic constructs that must be provided by an implementation. If the default memory ordering is specified as seq_cst, all atomic constructs on which memory-order-clause is not specified behave as if the seq_cst clause appears. If the default memory ordering is specified as relaxed, all atomic constructs on which memory-order-clause is not specified behave as if the relaxed clause appears.
If the default memory ordering is specified as acq_rel, atomic constructs on which memory-order-clause is not specified behave as if the release clause appears if the atomic write or atomic update operation is specified, as if the acquire clause appears if the atomic read operation is specified, and as if the acq_rel clause appears if the atomic captured update operation is specified.
Add support for Flush in the OMPIRBuilder. This patch also adds changes
to clang to use the OMPIRBuilder when '-fopenmp-enable-irbuilder'
commandline option is used.
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D70712
regions.
If the lastprivate conditional is passed as shared in inner region, we
shall check if it was ever changed and use this updated value after exit
from the inner region as an update value.
This is how it should've been and brings it more in line with
std::string_view. There should be no functional change here.
This is mostly mechanical from a custom clang-tidy check, with a lot of
manual fixups. It uncovers a lot of minor inefficiencies.
This doesn't actually modify StringRef yet, I'll do that in a follow-up.
regions with reductions, lastprivates or linears clauses.
If the lastprivate conditional variable is updated in inner parallel
region with reduction, lastprivate or linear clause, the value must be
considred as a candidate for lastprivate conditional. Also, tracking in
inner parallel regions is not required.
Use canonical decls instead of mangled names in the set of already
emitted decls. This allows to reduce the number of function calls for
getting declarations mangled names and speedup the compilation.
Added codegen support for lastprivate conditional. According to the
standard, if when the conditional modifier appears on the clause, if an
assignment to a list item is encountered in the construct then the
original list item is assigned the value that is assigned to the new
list item in the sequentially last iteration or lexically last section
in which such an assignment is encountered.
We look for the assignment operations and check if the left side
references lastprivate conditional variable. Then the next code is
emitted:
if (last_iv_a <= iv) {
last_iv_a = iv;
last_a = lp_a;
}
At the end the implicit barrier is generated to wait for the end of all
threads and then in the check for the last iteration the private copy is
assigned the last value.
if (last_iter) {
lp_a = last_a; // <--- new code
a = lp_a; // <--- store of private value to the original variable.
}
This removes the OpenMPProcBindClauseKind enum in favor of
llvm::omp::ProcBindKind which lives in OpenMPConstants.h and was
introduced in D70109.
No change in behavior is expected.
Reviewed By: JonChesterfield
Differential Revision: https://reviews.llvm.org/D70289
As a permanent and generic solution to the problem of variable
finalization (destructors, lastprivate, ...), this patch introduces the
finalization stack. The objects on the stack describe (1) the
(structured) regions the OpenMP-IR-Builder is currently constructing,
(2) if these are cancellable, and (3) the callback that will perform the
finalization (=cleanup) when necessary.
As the finalization can be necessary multiple times, at different source
locations, the callback takes the position at which code is currently
generated. This position will also encode the destination of the "region
exit" block *iff* the finalization call was issues for a region
generated by the OpenMPIRBuilder. For regions generated through the old
Clang OpenMP code geneneration, the "region exit" is determined by Clang
inside the finalization call instead (see getOMPCancelDestination).
As a first user, the parallel + cancel barrier interaction is changed.
In contrast to the temporary solution before, the barrier generation in
Clang does not need to be aware of the "CancelDestination" block.
Instead, the finalization callback is and, as described above, later
even that one does not need to be.
D70109 will be updated to use this scheme.
Reviewed By: ABataev
Differential Revision: https://reviews.llvm.org/D70258
Summary:
Basic codegen for the declarations marked as nontemporal. Also, if the
base declaration in the member expression is marked as nontemporal,
lvalue for member decl access inherits nonteporal flag from the base
lvalue.
Reviewers: rjmccall, hfinkel, jdoerfert
Subscribers: guansong, arphaman, caomhin, kkwli0, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D71708
in declare variant.
If the types of the fnction are not equal, but match, at the codegen
thei may have different types. This may lead to compiler crash.
This is a follow up patch to use the OpenMP-IR-Builder, as discussed on
the mailing list ([1] and later) and at the US Dev Meeting'19.
[1] http://lists.flang-compiler.org/pipermail/flang-dev_lists.flang-compiler.org/2019-May/000197.html
Reviewers: kiranchandramohan, ABataev, RaviNarayanaswamy, gtbercea, grokos, sdmitriev, JonChesterfield, hfinkel, fghanim
Subscribers: ppenzin, penzn, llvm-commits, cfe-commits, jfb, guansong, bollu, hiraditya, mgorny
Tags: #clang
Differential Revision: https://reviews.llvm.org/D69922
Summary:
The new OpenMPConstants.h is a location for all OpenMP related constants
(and helpers) to live.
This patch moves the directives there (the enum OpenMPDirectiveKind) and
rewires Clang to use the new location.
Initially part of D69785.
Reviewers: kiranchandramohan, ABataev, RaviNarayanaswamy, gtbercea, grokos, sdmitriev, JonChesterfield, hfinkel, fghanim
Subscribers: jholewinski, ppenzin, penzn, llvm-commits, cfe-commits, jfb, guansong, bollu, hiraditya, mgorny
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D69853
Johannes Doerfert