The `assumes` directive is an OpenMP 5.1 feature that allows the user to
provide assumptions to the optimizer. Assumptions can refer to
directives (`absent` and `contains` clauses), expressions (`holds`
clause), or generic properties (`no_openmp_routines`, `ext_ABCD`, ...).
The `assumes` spelling is used for assumptions in the global scope while
`assume` is used for executable contexts with an associated structured
block.
This patch only implements the global spellings. While clauses with
arguments are "accepted" by the parser, they will simply be ignored for
now. The implementation lowers the assumptions directly to the
`AssumptionAttr`.
Reviewed By: ABataev
Differential Revision: https://reviews.llvm.org/D91980
Since these are scoped enumerators, they have to be prefixed by DeclaratorContext, so lets remove Context from the name, and return some characters to the multiverse.
Patch was reviewed here: https://reviews.llvm.org/D91011
Thank you to aaron, bruno, wyatt and barry for indulging me.
ParseOpenMP.cpp was pretty much clang-formatted except a few minor
locations. Let's make it a clang formatted file.
Reviewed By: JonChesterfield
Differential Revision: https://reviews.llvm.org/D90440
With this extension the effects of `omp begin declare variant` will be
applied to template function declarations. The behavior is opt-in and
controlled by the `extension(allow_templates)` trait. While generally
useful, this will enable us to implement complex math function calls by
overloading the templates of the standard library with the ones in
libc++.
Reviewed By: JonChesterfield
Differential Revision: https://reviews.llvm.org/D85735
This extension allows to declare variants in between `omp begin/end
declare variant` that do not match the type of the existing function
with that name. Without this extension we would not find a base function
(with a compatible type), therefore create a new one, which would
cause conflicting declarations. With this extension we will not create
"missing" base functions, which basically renders these specializations
harmless. They will be generated but never called.
Reviewed By: JonChesterfield
Differential Revision: https://reviews.llvm.org/D85878
Due to `omp begin/end declare variant`, OpenMP context selectors can be
nested. This patch adds initial support for this so we can use it for
target math variants. We should improve the detection of "equivalent"
scores and user conditions, we should also revisit the data structures
of the OMPTraitInfo object, however, both are not pressing issues right
now.
Reviewed By: JonChesterfield
Differential Revision: https://reviews.llvm.org/D85877
Summary:
Introduced OMPChildren class to handle all associated clauses, statement
and child expressions/statements. It allows to represent some directives
more correctly (like flush, depobj etc. with pseudo clauses, ordered
depend directives, which are standalone, and target data directives).
Also, it will make easier to avoid using of CapturedStmt in directives,
if required (atomic, tile etc. directives).
Also, it simplifies serialization/deserialization of the
executable/declarative directives.
Reduces number of allocation operations for mapper declarations.
Reviewers: jdoerfert
Subscribers: yaxunl, guansong, jfb, cfe-commits, sstefan1, aaron.ballman, caomhin
Tags: #clang
Differential Revision: https://reviews.llvm.org/D83261
This patch implements Clang front end support for the OpenMP TR8
`present` motion modifier for `omp target update` directives. The
next patch in this series implements OpenMP runtime support.
Reviewed By: ABataev
Differential Revision: https://reviews.llvm.org/D84711
It was unclear what `isa` was supposed to mean so we did not provide any
traits for this context selector. With this patch we will allow *any*
string or identifier. We use the target attribute and target info to
determine if the trait matches. In other words, we will check if the
provided value is a target feature that is available (at the call site).
Fixes PR46338
Reviewed By: ABataev
Differential Revision: https://reviews.llvm.org/D83281
This patch implements Clang front end support for the OpenMP TR8
`present` motion modifier for `omp target update` directives. The
next patch in this series implements OpenMP runtime support.
Reviewed By: ABataev
Differential Revision: https://reviews.llvm.org/D84711
`to` and `from` clauses take the same modifiers, which are called
"motion modifiers" in TR8, so implement handling of their modifiers
once not twice. This will make it easier to implement additional
motion modifiers in the future.
Reviewed By: ABataev
Differential Revision: https://reviews.llvm.org/D84710
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
This implements the default(firstprivate) clause as defined in OpenMP
Technical Report 8 (2.22.4).
Reviewed By: jdoerfert, ABataev
Differential Revision: https://reviews.llvm.org/D75591
Summary:
This patch is removing the custom enumeration for OpenMP Directives and Clauses and replace them
with the newly tablegen generated one from llvm/Frontend. This is a first patch and some will follow to share the same
infrastructure where possible. The next patch should use the clauses allowance defined in the tablegen file.
Reviewers: jdoerfert, DavidTruby, sscalpone, kiranchandramohan, ichoyjx
Reviewed By: DavidTruby, ichoyjx
Subscribers: jholewinski, cfe-commits, dblaikie, MaskRay, ymandel, ichoyjx, mgorny, yaxunl, guansong, jfb, sstefan1, aaron.ballman, llvm-commits
Tags: #llvm, #flang, #clang
Differential Revision: https://reviews.llvm.org/D82906
Summary:
Previously OMPD_unknown was last item in the Directive enumeration and its position was
used in various comparison and assertion. With the new Directive enumeration, this should be
change with llvm::omp::Directive_enumSize. This patch fix two place where it was not done in
D81736.
Reviewers: vdmitrie, jdoerfert, jdenny
Reviewed By: jdoerfert
Subscribers: yaxunl, guansong, sstefan1, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D82518
C++ unqualified name lookup searches template parameter scopes
immediately after finishing searching the entity the parameters belong
to. (Eg, for a class template, you search the template parameter scope
after looking in that class template and its base classes and before
looking in the scope containing the class template.) This is complicated
by the fact that scope lookup within a template parameter scope looks in
a different sequence of places prior to reaching the end of the
declarator-id in the template declaration.
We used to approximate the proper lookup rule with a hack in the scope /
decl context walk inside name lookup. Now we instead compute the lookup
parent for each template parameter scope.
In order to get this right, we now make sure to enter a distinct Scope
for each template parameter scope, and make sure to re-enter the
enclosing class scopes properly when handling delay-parsed regions
within a class.
Summary:
As discussed previously when landing patch for OpenMP in Flang, the idea is
to share common part of the OpenMP declaration between the different Frontend.
While doing this it was thought that moving to tablegen instead of Macros will also
give a cleaner and more powerful way of generating these declaration.
This first part of a future series of patches is setting up the base .td file for
DirectiveLanguage as well as the OpenMP version of it. The base file is meant to
be used by other directive language such as OpenACC.
In this first patch, the Directive and Clause enums are generated with tablegen
instead of the macros on OMPConstants.h. The next pacth will extend this
to other enum and move the Flang frontend to use it.
Reviewers: jdoerfert, DavidTruby, fghanim, ABataev, jdenny, hfinkel, jhuber6, kiranchandramohan, kiranktp
Reviewed By: jdoerfert, jdenny
Subscribers: arphaman, martong, cfe-commits, mgorny, yaxunl, hiraditya, guansong, jfb, sstefan1, aaron.ballman, llvm-commits
Tags: #llvm, #openmp, #clang
Differential Revision: https://reviews.llvm.org/D81736
Summary:
As discussed previously when landing patch for OpenMP in Flang, the idea is
to share common part of the OpenMP declaration between the different Frontend.
While doing this it was thought that moving to tablegen instead of Macros will also
give a cleaner and more powerful way of generating these declaration.
This first part of a future series of patches is setting up the base .td file for
DirectiveLanguage as well as the OpenMP version of it. The base file is meant to
be used by other directive language such as OpenACC.
In this first patch, the Directive and Clause enums are generated with tablegen
instead of the macros on OMPConstants.h. The next pacth will extend this
to other enum and move the Flang frontend to use it.
Reviewers: jdoerfert, DavidTruby, fghanim, ABataev, jdenny, hfinkel, jhuber6, kiranchandramohan, kiranktp
Reviewed By: jdoerfert, jdenny
Subscribers: cfe-commits, mgorny, yaxunl, hiraditya, guansong, jfb, sstefan1, aaron.ballman, llvm-commits
Tags: #llvm, #openmp, #clang
Differential Revision: https://reviews.llvm.org/D81736
Summary:
Compiler may erroneously treat current context in OpenMP pragmas as the
context where new type declaration/definition is allowed. But the
declartation/definition of the new types in OpenMP pragmas should not be
allowed.
Reviewers: jdoerfert
Subscribers: yaxunl, guansong, sstefan1, cfe-commits, caomhin
Tags: #clang
Differential Revision: https://reviews.llvm.org/D82019
Summary:
According to the standard, variable-category is the optional part of the
defaultmap clause while the compiler always requires it. Turned it into
optional part.
Reviewers: jdoerfert
Subscribers: yaxunl, guansong, cfe-commits, caomhin
Tags: #clang
Differential Revision: https://reviews.llvm.org/D77751
By default, all traits in the OpenMP context selector have to match for
it to be acceptable. Though, we sometimes want a single property out of
multiple to match (=any) or no match at all (=none). We offer these
choices as extensions via
`implementation={extension(match_{all,any,none})}`
to the user. The choice will affect the entire context selector not only
the traits following the match property.
The first user will be D75788. There we can replace
```
#pragma omp begin declare variant match(device={arch(nvptx64)})
#define __CUDA__
#include <__clang_cuda_cmath.h>
// TODO: Hack until we support an extension to the match clause that allows "or".
#undef __CLANG_CUDA_CMATH_H__
#undef __CUDA__
#pragma omp end declare variant
#pragma omp begin declare variant match(device={arch(nvptx)})
#define __CUDA__
#include <__clang_cuda_cmath.h>
#undef __CUDA__
#pragma omp end declare variant
```
with the much simpler
```
#pragma omp begin declare variant match(device={arch(nvptx, nvptx64)}, implementation={extension(match_any)})
#define __CUDA__
#include <__clang_cuda_cmath.h>
#undef __CUDA__
#pragma omp end declare variant
```
Reviewed By: mikerice
Differential Revision: https://reviews.llvm.org/D77414
This is a cleanup and normalization patch that also enables reuse with
Flang later on. A follow up will clean up and move the directive ->
clauses mapping.
Reviewed By: fghanim
Differential Revision: https://reviews.llvm.org/D77112
See rational here: https://reviews.llvm.org/D76173#1922916
Time to compile Attr.h in isolation goes from 2.6s to 1.8s.
Original patch by Johannes, plus some additions from Reid to fix some
clang tooling targets.
Effect on transitive includes is marginal, though:
$ diff -u <(sort thedeps-before.txt) <(sort thedeps-after.txt) \
| grep '^[-+] ' | sort | uniq -c | sort -nr
104 - /usr/local/google/home/rnk/llvm-project/clang/include/clang/AST/OpenMPClause.h
87 - /usr/local/google/home/rnk/llvm-project/llvm/include/llvm/Frontend/OpenMP/OMPContext.h
19 - /usr/local/google/home/rnk/llvm-project/llvm/include/llvm/ADT/SmallSet.h
19 - /usr/local/google/home/rnk/llvm-project/llvm/include/llvm/ADT/SetVector.h
14 - /usr/include/c++/9/set
...
Differential Revision: https://reviews.llvm.org/D76184
This is a cleanup and normalization patch that also enables reuse with
Flang later on. A follow up will clean up and move the directive ->
clauses mapping.
Differential Revision: https://reviews.llvm.org/D77112
This is the second part loosely extracted from D71179 and cleaned up.
This patch provides semantic analysis support for `omp begin/end declare
variant`, mostly as defined in OpenMP technical report 8 (TR8) [0].
The sema handling makes code generation obsolete as we generate "the
right" calls that can just be handled as usual. This handling also
applies to the existing, albeit problematic, `omp declare variant
support`. As a consequence a lot of unneeded code generation and
complexity is removed.
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].
The logic is as follows:
If we have seen a `#pragma omp begin declare variant match(<SELECTOR>)`
but not the corresponding `end declare variant`, and we find a function
definition we will:
1) Create a function declaration for the definition we were about to generate.
2) Create a function definition but with a mangled name (according to
`<SELECTOR>`).
3) Annotate the declaration with the `OMPDeclareVariantAttr`, the same
one used already for `omp declare variant`, using and the mangled
function definition as specialization for the context defined by
`<SELECTOR>`.
When a call is created we inspect it. If the target has an
`OMPDeclareVariantAttr` attribute we try to specialize the call. To this
end, all variants are checked, the best applicable one is picked and a
new call to the specialization is created. The new call is used instead
of the original one to the base function. To keep the AST printing and
tooling possible we utilize the PseudoObjectExpr. The original call is
the syntactic expression, the specialized call is the semantic
expression.
[0] https://www.openmp.org/wp-content/uploads/openmp-TR8.pdf
[1] https://reviews.llvm.org/D61399#change-496lQkg0mhRN
Reviewers: kiranchandramohan, ABataev, RaviNarayanaswamy, gtbercea, grokos, sdmitriev, JonChesterfield, hfinkel, fghanim, aaron.ballman
Subscribers: bollu, guansong, openmp-commits, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D75779
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
Suppress those diagnostics if lhs of a member expression contains
errors. Typo correction produces dependent expressions even in
non-template code, that led to spurious diagnostics before.
previous:
/tmp/t.cpp:6:17: error: use 'template' keyword to treat 'f' as a dependent template name
auto a = bilder.f<int>();
^
template
/tmp/t.cpp:6:10: error: use of undeclared identifier 'bilder'; did you mean 'builder'?
auto a = bilder.f<int>();
^~~~~~
builder
vs now:
/tmp/t.cpp:6:10: error: use of undeclared identifier 'bilder'; did you mean 'builder'?
auto a = bilder.f<int>();
^~~~~~
builder
Original patch from Ilya.
Reviewers: sammccall
Reviewed By: sammccall
Tags: #clang
Differential Revision: https://reviews.llvm.org/D65592
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
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.
Function trailing requires clauses now parsed, supported in overload resolution and when calling, referencing and taking the address of functions or function templates.
Differential Revision: https://reviews.llvm.org/D43357
If standalone OpenMP declaration pragma, like declare mapper or declare
reduction, is declared in the class context, it may reference a member
(data or function) in its internal expressions/statements. So, the
parsing of such pragmas must be dalayed just like the parsing of the
member initializers/definitions before the completion of the class
declaration.
When parsing the code with OpenMP and the function's body must be
skipped, need to skip also OpenMP annotation tokens. Otherwise the
counters for braces/parens are unbalanced and parsing fails.
variant directive.
If the function is used only in declare variant directive as a variant
function, it should not be marked as used to prevent emission of the
target-specific functions. Build the reference in the unevaluated
context.
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
According to OpenMP 5.0, if clause can be used in simd directive. If
condition in the if clause if false, the non-vectorized version of the
loop must be executed.
Summary:
For the extended defaultmap, most of the work is inside sema.
The only difference for codegen is to set different initial
maptype for different implicit-behavior.
Reviewers: jdoerfert, ABataev
Reviewed By: ABataev
Subscribers: dreachem, sandoval, cfe-commits
Tags: #clang, #openmp
Differential Revision: https://reviews.llvm.org/D69204
If the context selector score was not specified, its value must be set
to 0. Simplify the processing of unspecified scores + save memory in
attribute representation.
Added parsing/sema/codegen support for 'parallel master taskloop'
constructs. Some of the clauses, like 'grainsize', 'num_tasks', 'final'
and 'priority' are not supported in full, only constant expressions can
be used currently in these clauses.
llvm-svn: 374791
and of vendors, not or.
If several vendors are provided in the same vendor context trait, the
context shall match only if all vendors are matching, not one of them.
This is per OpenMP 5.0, 2.3.3 Matching and Scoring Context Selectors,
all selectors in the construct, device, and implementation sets of the
context selector appear in the corresponding trait set of the OpenMP
context.
llvm-svn: 374107
selector.
According to OpenMP 5.0, 2.3.2 Context Selectors, Restrictions, each
trait-selector-name can only be specified once. Added check for this
restriction.
llvm-svn: 374093
According to OpenMP 5.0, 2.3.2 Context Selectors, Restrictions, each
trait-set-selector-name can only be specified once. Added check to
implement this restriction.
llvm-svn: 374072
Context selectors may include optional score clause in format
`score(<expr>):`, where `<expr>` must be a constant integer expression.
Added parsing/sema analysis only.
llvm-svn: 373502
sets.
According to OpenMP 5.0, context selector set might include several
context selectors, separated with commas. Patch fixes this problem.
llvm-svn: 372235
construct.
OpenMP 5.0 introduced new clause for declare target directive, device_type clause, which may accept values host, nohost, and any. Host means
that the function must be emitted only for the host, nohost - only for
the device, and any - for both, device and the host.
llvm-svn: 369775
Summary:
By adding a hook to consume all tokens produced by the preprocessor.
The intention of this change is to make it possible to consume the
expanded tokens without re-runnig the preprocessor with minimal changes
to the preprocessor and minimal performance penalty when preprocessing
without recording the tokens.
The added hook is very low-level and reconstructing the expanded token
stream requires more work in the client code, the actual algorithm to
collect the tokens using this hook can be found in the follow-up change.
Reviewers: rsmith
Reviewed By: rsmith
Subscribers: eraman, nemanjai, kbarton, jsji, riccibruno, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D59885
llvm-svn: 361007
Summary:
See the added test for some new cases.
This change also removes special code completion calls inside the
ParseExpressionList function now that we properly propagate expected
type to the function responsible for parsing elements of the expression list
(ParseAssignmentExpression).
Reviewers: kadircet
Reviewed By: kadircet
Subscribers: xbolva00, jdoerfert, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D58541
llvm-svn: 354864
This patch implements the parsing and sema support for the OpenMP
'from'-clause with potential user-defined mappers attached.
User-defined mappers are a new feature in OpenMP 5.0. A 'from'-clause
can have an explicit or implicit associated mapper, which instructs the
compiler to generate and use customized mapping functions. 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 update from(mapper(id): ss) // use the mapper with name 'id' to map ss from device
Contributed-by: Lingda Li <lildmh@gmail.com>
Differential Revision: https://reviews.llvm.org/D58638
llvm-svn: 354817
This patch implements the parsing and sema support for OpenMP to clause
with potential user-defined mappers attached. User defined mapper is a
new feature in OpenMP 5.0. A to/from clause can have an explicit or
implicit associated mapper, which instructs the compiler to generate and
use customized mapping functions. 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 update to(mapper(id): ss) // use the mapper with name 'id' to map ss to device
Contributed-by: <lildmh@gmail.com>
Differential Revision: https://reviews.llvm.org/D58523
llvm-svn: 354698
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