If the statements between target|teams|distribute directives does not
require execution in master thread, like constant expressions, null
statements, simple declarations, etc., such construct can be xecuted in
SPMD mode.
llvm-svn: 346551
target|teams|distribute variables.
If the total size of the variables, declared in target|teams|distribute
regions, is less than the maximal size of shared memory available, the
buffer is allocated in the shared memory.
llvm-svn: 346507
The base pointer for the lambda mapping must point to the lambda capture
placement and pointer must point to the captured variable itself. Patch
fixes this problem.
llvm-svn: 346408
Fixed lookup for the target regions in unused virtual functions + fixed
processing of the global variables not marked as declare target but
emitted during debug info emission.
llvm-svn: 346343
Coalesced memory access requires use of the new function
`__kmpc_data_sharing_coalesced_push_stack` instead of the
`__kmpc_data_sharing_push_stack`.
llvm-svn: 345991
The previously used combination `PTR_AND_OBJ | PRIVATE` could be used for mapping of some data in Fortran. Changed it to `PTR_AND_OBJ | LITERAL`.
llvm-svn: 345982
target/teams/distribute regions.
Target/teams/distribute regions exist for all the time the kernel is
executed. Thus, if the variable is declared in their context and then
escape it, we can allocate global memory statically instead of
allocating it dynamically.
Patch captures all the globalized variables in target/teams/distribute
contexts, merges them into the records, one per each target region.
Those records are then joined into the union, one per compilation unit
(to save the global memory). Those units are organized into
2 x dimensional arrays, where the first dimension is
the number of blocks per SM and the second one is the number of SMs.
Runtime functions manage this global memory space between the executing
teams.
llvm-svn: 345978
Added support for mapping of lambdas in the target regions. It scans all
the captures by reference in the lambda, implicitly maps those variables
in the target region and then later reinstate the addresses of
references in lambda to the correct addresses of the captured|privatized
variables.
llvm-svn: 345609
being shared.
According to the standard, the variables with unspecified data-sharing
attributes in presence of `default(none)` clause must be reported to
users. Compiler did not generate error reports for the variables used in
other OpenMP regions. Patch fixes this.
llvm-svn: 345533
Summary: Iteration variable must be strictly less than the number of iterations. This fixes a bug introduced by previous patch D53448.
Reviewers: ABataev, caomhin
Reviewed By: ABataev
Subscribers: guansong, cfe-commits
Differential Revision: https://reviews.llvm.org/D53827
llvm-svn: 345527
Summary: This patch adds a new code generation path for bound sharing directives containing distribute parallel for. The new code generation scheme applies to chunked schedules on distribute and parallel for directives. The scheme simplifies the code that is being generated by eliminating the need for an outer for loop over chunks for both distribute and parallel for directives. In the case of distribute it applies to any sized chunk while in the parallel for case it only applies when chunk size is 1.
Reviewers: ABataev, caomhin
Reviewed By: ABataev
Subscribers: jholewinski, guansong, cfe-commits
Differential Revision: https://reviews.llvm.org/D53448
llvm-svn: 345509
Summary: This patch enables the choosing of the default schedule for parallel for loops even in non-SPMD cases.
Reviewers: ABataev, caomhin
Reviewed By: ABataev
Subscribers: jholewinski, guansong, cfe-commits
Differential Revision: https://reviews.llvm.org/D53443
llvm-svn: 345507
If the loop counter is not declared in the context of the loop and it is
private, such loop counters should not be captured in the outlined
regions.
llvm-svn: 345505
Summary:
This is a simple test of the parallel for code generation. It will be used to showcase the change introduced by patch D53443.
Reviewers: ABataev, caomhin
Reviewed By: ABataev
Subscribers: guansong, cfe-commits
Differential Revision: https://reviews.llvm.org/D53772
llvm-svn: 345417
According to the OpenMP standard, In a task generating construct, if no
default clause is present, a variable for which the data-sharing
attribute is not determined by the rules above is firstprivatized.
Compiler tries to implement this, but if the variable is not directly
used in the task context, this variable may not be firstprivatized.
Patch fixes this problem.
llvm-svn: 345277
Summary:
For the following code:
```
int i;
#pragma omp taskloop
for (i = 0; i < 100; ++i)
{}
#pragma omp taskloop nogroup
for (i = 0; i < 100; ++i)
{}
```
Clang emits the following LLVM IR:
```
...
call void @__kmpc_taskgroup(%struct.ident_t* @0, i32 %0)
%2 = call i8* @__kmpc_omp_task_alloc(%struct.ident_t* @0, i32 %0, i32 1, i64 80, i64 8, i32 (i32, i8*)* bitcast (i32 (i32, %struct.kmp_task_t_with_privates*)* @.omp_task_entry. to i32 (i32, i8*)*))
...
call void @__kmpc_taskloop(%struct.ident_t* @0, i32 %0, i8* %2, i32 1, i64* %8, i64* %9, i64 %13, i32 0, i32 0, i64 0, i8* null)
call void @__kmpc_end_taskgroup(%struct.ident_t* @0, i32 %0)
...
%15 = call i8* @__kmpc_omp_task_alloc(%struct.ident_t* @0, i32 %0, i32 1, i64 80, i64 8, i32 (i32, i8*)* bitcast (i32 (i32, %struct.kmp_task_t_with_privates.1*)* @.omp_task_entry..2 to i32 (i32, i8*)*))
...
call void @__kmpc_taskloop(%struct.ident_t* @0, i32 %0, i8* %15, i32 1, i64* %21, i64* %22, i64 %26, i32 0, i32 0, i64 0, i8* null)
```
The first set of instructions corresponds to the first taskloop construct. It is important to note that the implicit taskgroup region associated with the taskloop construct has been materialized in our IR: the `__kmpc_taskloop` occurs inside a taskgroup region. Note also that this taskgroup region does not exist in our second taskloop because we are using the `nogroup` clause.
The issue here is the 4th argument of the kmpc_taskloop call, starting from the end, is always a zero. Checking the LLVM OpenMP RT implementation, we see that this argument corresponds to the nogroup parameter:
```
void __kmpc_taskloop(ident_t *loc, int gtid, kmp_task_t *task, int if_val,
kmp_uint64 *lb, kmp_uint64 *ub, kmp_int64 st, int nogroup,
int sched, kmp_uint64 grainsize, void *task_dup);
```
So basically we always tell to the RT to do another taskgroup region. For the first taskloop, this means that we create two taskgroup regions. For the second example, it means that despite the fact we had a nogroup clause we are going to have a taskgroup region, so we unnecessary wait until all descendant tasks have been executed.
Reviewers: ABataev
Reviewed By: ABataev
Subscribers: rogfer01, cfe-commits
Differential Revision: https://reviews.llvm.org/D53636
llvm-svn: 345180
The compiler is crashing if we trying to post-capture the fields
implicitly captured inside of the task constructs. Seems, this kind of
processing is not supported and such fields should not be
firstprivatized.
llvm-svn: 345177
This reverts commit https://reviews.llvm.org/rL344150 which causes
MachineOutliner related failures on the ppc64le multistage buildbot.
llvm-svn: 344526
if the function has globalized variables and called in context of
target/teams/distribute regions, it does not need to globalize 32
copies of the same variables for memory coalescing, it is enough to
have just one copy, because there is parallel region.
Patch does this by adding call for `__kmpc_parallel_level` function and
checking its return value. If the code sees that the parallel level is
0, then only one variable is allocated, not 32.
llvm-svn: 344356
target/teams/distribute regions.
Previously introduced globalization scheme that uses memory coalescing
scheme may increase memory usage fr the variables that are devlared in
target/teams/distribute contexts. We don't need 32 copies of such
variables, just 1. Patch reduces memory use in this case.
llvm-svn: 344273
This is currently a clang extension and a resolution
of the defect report in the C++ Standard.
Differential Revision: https://reviews.llvm.org/D46441
llvm-svn: 344150
Added support for memory coalescing for better performance for
globalized variables. From now on all the globalized variables are
represented as arrays of 32 elements and each thread accesses these
elements using `tid & 31` as index.
llvm-svn: 344049
Fixed emission of the __kmpc_global_thread_num() so that it is not
messed up with alloca instructions anymore. Plus, fixes emission of the
__kmpc_global_thread_num() functions in the target outlined regions so
that they are not called before runtime is initialized.
llvm-svn: 343856
Worker threads fork off to the compiler generated worker function
directly after entering the kernel function. Hence, there is no
need to check whether the current thread is the master if we are
outside of a parallel region (neither SPMD nor parallel_level > 0).
Differential Revision: https://reviews.llvm.org/D52732
llvm-svn: 343618
lightweight runtime.
The datasharing flag must be set to `1` when executing SPMD-mode compatible directive with reduction|lastprivate clauses.
llvm-svn: 343492
According to OpenMP, the reduction item must be shared in parent region.
But the item can be an array section or array subscript. In this case,
we should not check for the datasharing of the base declaration.
llvm-svn: 343356
Summary: Set default schedule for parallel for loops to schedule(static, 1) when using SPMD mode on the NVPTX device offloading toolchain to ensure coalescing.
Reviewers: ABataev, Hahnfeld, caomhin
Reviewed By: ABataev
Subscribers: jholewinski, guansong, cfe-commits
Differential Revision: https://reviews.llvm.org/D52629
llvm-svn: 343260
Summary: For the OpenMP NVPTX toolchain choose a default distribute schedule that ensures coalescing on the GPU when in SPMD mode. This significantly increases the performance of offloaded target code and reduces the number of registers used on the GPU side.
Reviewers: ABataev, caomhin, Hahnfeld
Reviewed By: ABataev, Hahnfeld
Subscribers: Hahnfeld, jholewinski, guansong, cfe-commits
Differential Revision: https://reviews.llvm.org/D52434
llvm-svn: 343253
Add support for OMP5.0 requires directive and unified_address clause.
Patches to follow will include support for additional clauses.
Differential Revision: https://reviews.llvm.org/D52359
llvm-svn: 343063
declare reduction.
If the declare reduction construct with the non-dependent type is
defined in the template construct, the compiler might crash on the
template instantition. Reworked the whole instantiation scheme for the
declare reduction constructs to fix this problem correctly.
llvm-svn: 342151
Sema analysis should not mark functions as an implicit declare target,
it may break codegen. Simplified semantic analysis and removed extra
code for implicit declare target functions.
llvm-svn: 341939
Add the capability to nest multiple declare target directives
- including header files within a declare target region.
Differential Revision: https://reviews.llvm.org/D51378
Patch by Patrick Lyster
llvm-svn: 341766
context.
If the explicit template instantiation definition defined outside of the
target context, its vtable should not be marked as used. This is true
for other situations where the compiler want to emit vtables
unconditionally.
llvm-svn: 341570
'declare target'.
All the functions, referenced in implicit|explicit target regions must
be emitted during code emission for the device.
llvm-svn: 341093
If the target construct can be executed in SPMD mode + it is a loop
based directive with static scheduling, we can use lightweight runtime
support.
llvm-svn: 340953
Currently ident_t objects are created const when debug info is not
enabled, but the libittnotify libray in the OpenMP runtime writes to
the reserved_2 field (See __kmp_itt_region_forking in
openmp/runtime/src/kmp_itt.inl). Now create ident_t objects non-const.
Differential Revision: https://reviews.llvm.org/D51331
llvm-svn: 340934
Alexey Bataev