[OpenMP][libomp] Fix /dev/shm pollution after forked child process terminates

Made library registration conditional and skip it in the __kmp_atfork_child
handler, postponed it till middle initializa

[OpenMP][libomp] Fix /dev/shm pollution after forked child process terminates

Made library registration conditional and skip it in the __kmp_atfork_child
handler, postponed it till middle initialization in the child.
This fixes the problem of applications those use e.g. popen/pclose
which terminate the forked child process.

Differential Revision: https://reviews.llvm.org/D125996

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[OpenMP][libomp] Add support for offline CPUs in Linux

If some CPUs are offline, then make sure they are not included in the
fullMask even if norespect is given to KMP_AFFINITY.

Differential Revisi

[OpenMP][libomp] Add support for offline CPUs in Linux

If some CPUs are offline, then make sure they are not included in the
fullMask even if norespect is given to KMP_AFFINITY.

Differential Revision: https://reviews.llvm.org/D112274

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[OpenMP][libomp][NFC] Remove non-ASCII apostrophe in comment

[OpenMP][NFC] libomp: silence warnings on unused variables.

Put declarations/definitions of unused variables under corresponding macros
to silence clang build warnings.

Differential Revision: https

[OpenMP][NFC] libomp: silence warnings on unused variables.

Put declarations/definitions of unused variables under corresponding macros
to silence clang build warnings.

Differential Revision: https://reviews.llvm.org/D106608

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[OpenMP] libomp: Add new experimental barrier: two-level distributed barrier

Two-level distributed barrier is a new experimental barrier designed
for Intel hardware that has better performance in so

[OpenMP] libomp: Add new experimental barrier: two-level distributed barrier

Two-level distributed barrier is a new experimental barrier designed
for Intel hardware that has better performance in some cases than the
default hyper barrier.

This barrier is designed to handle fine granularity parallelism where
barriers are used frequently with little compute and memory access
between barriers. There is no need to use it for codes with few
barriers and large granularity compute, or memory intensive
applications, as little difference will be seen between this barrier
and the default hyper barrier. This barrier is designed to work
optimally with a fixed number of threads, and has a significant setup
time, so should NOT be used in situations where the number of threads
in a team is varied frequently.

The two-level distributed barrier is off by default -- hyper barrier
is used by default. To use this barrier, you must set all barrier
patterns to use this type, because it will not work with other barrier
patterns. Thus, to turn it on, the following settings are required:

KMP_FORKJOIN_BARRIER_PATTERN=dist,dist
KMP_PLAIN_BARRIER_PATTERN=dist,dist
KMP_REDUCTION_BARRIER_PATTERN=dist,dist

Branching factors (set with KMP_FORKJOIN_BARRIER, KMP_PLAIN_BARRIER,
and KMP_REDUCTION_BARRIER) are ignored by the two-level distributed
barrier.

Patch fixed for ITTNotify disabled builds and non-x86 builds

Co-authored-by: Jonathan Peyton <[email protected]>
Co-authored-by: Vladislav Vinogradov <[email protected]>

Differential Revision: https://reviews.llvm.org/D103121

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[OpenMP] Remove TSAN annotations from libomp

The annotations in libomp were never built by default. The annotations are
also superseded by the annotations which the OMPT tool libarcher.so provides.

[OpenMP] Remove TSAN annotations from libomp

The annotations in libomp were never built by default. The annotations are
also superseded by the annotations which the OMPT tool libarcher.so provides.
With respect to libarcher, libomp behaves as if libarcher would be the last
element of OMP_TOOL_LIBARARIES. I.e., if no other OMPT tool gets active,
libarcher will check if an OpenMP application is built with TSan.

Since libarcher gets loaded by default, enabling LIBOMP_TSAN_SUPPORT would
result in redundant annotations for TSan, which slightly differ in details
and coverage (e.g. task dependencies are not handled well by the annotations
in libomp).

This patch removes all TSan annotations from the OpenMP runtime code.

Differential Revision: https://reviews.llvm.org/D103767

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[OpenMP] Fix a few issues with hidden helper task

This patch includes the following changes to address a few issues when
using hidden helper task.

- Assertion is triggered when there are inadverten

[OpenMP] Fix a few issues with hidden helper task

This patch includes the following changes to address a few issues when
using hidden helper task.

- Assertion is triggered when there are inadvertent calls to hidden
helper functions on non-Linux OS
- Added deinit code in __kmp_internal_end_library function to fix random
shutdown crashes
- Moved task data access into the lock-guarded region in __kmp_push_task

Differential Revision: https://reviews.llvm.org/D105308

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Revert "[OpenMP] Add Two-level Distributed Barrier"

This reverts commit 25073a4ecfc9b2e3cb76776185e63bfdb094cd98.

This breaks non-x86 OpenMP builds for a while now. Until a solution is
ready to be

Revert "[OpenMP] Add Two-level Distributed Barrier"

This reverts commit 25073a4ecfc9b2e3cb76776185e63bfdb094cd98.

This breaks non-x86 OpenMP builds for a while now. Until a solution is
ready to be upstreamed we revert the feature and unblock those builds.
See:
https://reviews.llvm.org/rG25073a4ecfc9b2e3cb76776185e63bfdb094cd98#1005821
and
https://reviews.llvm.org/rG25073a4ecfc9b2e3cb76776185e63bfdb094cd98#1005821

The currently proposed fix (D104788) seems not to be ready yet:
https://reviews.llvm.org/D104788#2841928

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[OpenMP] Add Two-level Distributed Barrier

Two-level distributed barrier is a new experimental barrier designed
for Intel hardware that has better performance in some cases than the
default hyper ba

[OpenMP] Add Two-level Distributed Barrier

Two-level distributed barrier is a new experimental barrier designed
for Intel hardware that has better performance in some cases than the
default hyper barrier.

This barrier is designed to handle fine granularity parallelism where
barriers are used frequently with little compute and memory access
between barriers. There is no need to use it for codes with few
barriers and large granularity compute, or memory intensive
applications, as little difference will be seen between this barrier
and the default hyper barrier. This barrier is designed to work
optimally with a fixed number of threads, and has a significant setup
time, so should NOT be used in situations where the number of threads
in a team is varied frequently.

The two-level distributed barrier is off by default -- hyper barrier
is used by default. To use this barrier, you must set all barrier
patterns to use this type, because it will not work with other barrier
patterns. Thus, to turn it on, the following settings are required:

KMP_FORKJOIN_BARRIER_PATTERN=dist,dist
KMP_PLAIN_BARRIER_PATTERN=dist,dist
KMP_REDUCTION_BARRIER_PATTERN=dist,dist

Branching factors (set with KMP_FORKJOIN_BARRIER, KMP_PLAIN_BARRIER,
and KMP_REDUCTION_BARRIER) are ignored by the two-level distributed
barrier.

Differential Revision: https://reviews.llvm.org/D103121

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[OpenMP] Remove unused variables from libomp code

Several variables were left unused as a result of different patches removing
their use.

Two variables have some use:
`poll_count` is used by the KM

[OpenMP] Remove unused variables from libomp code

Several variables were left unused as a result of different patches removing
their use.

Two variables have some use:
`poll_count` is used by the KMP_BLOCKING macro only under certain conditions.
Adding (void) to tell the compiler to ignore the unused variable.

`padding` is a dummy stack allocation with no intent to be used. Also adding
(void) to make the compiler ignore the unused variable.

Differential Revision: https://reviews.llvm.org/D104303

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[OpenMP] Fix affinity determine capable algorithm on Linux

Remove strange checks for syscall() arguments where mask is NULL.
Valgrind reports these as error usages for the syscall.
Instead, just che

[OpenMP] Fix affinity determine capable algorithm on Linux

Remove strange checks for syscall() arguments where mask is NULL.
Valgrind reports these as error usages for the syscall.
Instead, just check if CACHE_LINE bytes is long enough. If not, then
search for the size. Also, by limiting the first size detection
attempt to CACHE_LINE bytes, instead of 1MB, we don't use more than one
cache line for the mask size. Before this patch, sometimes the returned
mask size was 640 bytes (10 cache lines) because the initial call to
getaffinity() was limited only by the internal kernel mask size
which can be very large.

Differential Revision: https://reviews.llvm.org/D103637

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[OpenMP] Allow affinity to re-detect for child processes

Current atfork() handler for child processes does not reset
the affinity masks array which prevents users from setting their own
affinity in

[OpenMP] Allow affinity to re-detect for child processes

Current atfork() handler for child processes does not reset
the affinity masks array which prevents users from setting their own
affinity in child processes.

Differential Revision: https://reviews.llvm.org/D99218

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[OpenMP] libomp: cleanup some resource leaks

Close mutexattr and condattr local objects to eliminate resource leaks.

Differential Revision: https://reviews.llvm.org/D96892

[OpenMP][NFC] clang-format the whole openmp project

Same script as D95318. Test files are excluded.

Reviewed By: AndreyChurbanov

Differential Revision: https://reviews.llvm.org/D97088

[OpenMP] Added the support for hidden helper task in RTL

The basic design is to create an outer-most parallel team. It is not a regular team because it is only created when the first hidden helper t

[OpenMP] Added the support for hidden helper task in RTL

The basic design is to create an outer-most parallel team. It is not a regular team because it is only created when the first hidden helper task is encountered, and is only responsible for the execution of hidden helper tasks. We first use `pthread_create` to create a new thread, let's call it the initial and also the main thread of the hidden helper team. This initial thread then initializes a new root, just like what RTL does in initialization. After that, it directly calls `__kmpc_fork_call`. It is like the initial thread encounters a parallel region. The wrapped function for this team is, for main thread, which is the initial thread that we create via `pthread_create` on Linux, waits on a condition variable. The condition variable can only be signaled when RTL is being destroyed. For other work threads, they just do nothing. The reason that main thread needs to wait there is, in current implementation, once the main thread finishes the wrapped function of this team, it starts to free the team which is not what we want.

Two environment variables, `LIBOMP_NUM_HIDDEN_HELPER_THREADS` and `LIBOMP_USE_HIDDEN_HELPER_TASK`, are also set to configure the number of threads and enable/disable this feature. By default, the number of hidden helper threads is 8.

Here are some open issues to be discussed:
1. The main thread goes to sleeping when the initialization is finished. As Andrey mentioned, we might need it to be awaken from time to time to do some stuffs. What kind of update/check should be put here?

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D77609

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Revert "[OpenMP] Added the support for hidden helper task in RTL"

This reverts commit ed939f853da1f2266f00ea087f778fda88848f73.

[OpenMP] Added the support for hidden helper task in RTL

The basic design is to create an outer-most parallel team. It is not a regular team because it is only created when the first hidden helper t

[OpenMP] Added the support for hidden helper task in RTL

The basic design is to create an outer-most parallel team. It is not a regular team because it is only created when the first hidden helper task is encountered, and is only responsible for the execution of hidden helper tasks. We first use `pthread_create` to create a new thread, let's call it the initial and also the main thread of the hidden helper team. This initial thread then initializes a new root, just like what RTL does in initialization. After that, it directly calls `__kmpc_fork_call`. It is like the initial thread encounters a parallel region. The wrapped function for this team is, for main thread, which is the initial thread that we create via `pthread_create` on Linux, waits on a condition variable. The condition variable can only be signaled when RTL is being destroyed. For other work threads, they just do nothing. The reason that main thread needs to wait there is, in current implementation, once the main thread finishes the wrapped function of this team, it starts to free the team which is not what we want.

Two environment variables, `LIBOMP_NUM_HIDDEN_HELPER_THREADS` and `LIBOMP_USE_HIDDEN_HELPER_TASK`, are also set to configure the number of threads and enable/disable this feature. By default, the number of hidden helper threads is 8.

Here are some open issues to be discussed:
1. The main thread goes to sleeping when the initialization is finished. As Andrey mentioned, we might need it to be awaken from time to time to do some stuffs. What kind of update/check should be put here?

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D77609

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[OpenMP] libomp: Handle implicit conversion warnings

This patch partially prepares the runtime source code to be built with
-Wconversion, which should trigger warnings if any implicit conversions
ca

[OpenMP] libomp: Handle implicit conversion warnings

This patch partially prepares the runtime source code to be built with
-Wconversion, which should trigger warnings if any implicit conversions
can possibly change a value. For builds done with icc or gcc, all such
warnings are handled in this patch. clang gives a much longer list of
warnings, particularly for sign conversions, which the other compilers
don't report. The -Wconversion flag is commented into cmake files, but
I'm not going to turn it on. If someone thinks it is important, and wants
to fix all the clang warnings, they are welcome to.

Types of changes made here involve either improving the consistency of types
used so that no conversion is needed, or else performing careful explicit
conversions, when we're sure a problem won't arise.

Patch is a combination of changes by Terry Wilmarth and Johnny Peyton.

Differential Revision: https://reviews.llvm.org/D92942

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[OpenMP] Initialize runtime in the forked child process

This patch enables serial initialization in the forked child process
to fix unstable runtime behavior when used with Python-based AI tools.

D

[OpenMP] Initialize runtime in the forked child process

This patch enables serial initialization in the forked child process
to fix unstable runtime behavior when used with Python-based AI tools.

Differential Revision: https://reviews.llvm.org/D93230

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[OpenMP] Add support for Intel's umonitor/umwait

These changes add support for Intel's umonitor/umwait usage in wait
code, for architectures that support those intrinsic functions. Usage of
umonitor

[OpenMP] Add support for Intel's umonitor/umwait

These changes add support for Intel's umonitor/umwait usage in wait
code, for architectures that support those intrinsic functions. Usage of
umonitor/umwait is off by default, but can be turned on by setting the
KMP_USER_LEVEL_MWAIT environment variable.

Differential Revision: https://reviews.llvm.org/D91189

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[OpenMP] libomp: change shm name to include UID, call unregister_lib on SIGTERM

With the change to using shared memory, there were a few problems that need to be fixed.
- The previous filename that

[OpenMP] libomp: change shm name to include UID, call unregister_lib on SIGTERM

With the change to using shared memory, there were a few problems that need to be fixed.
- The previous filename that was used for SHM only used process id. Given that process is
usually based on 16bit number, this was causing some conflicts on machines. Thus we add
UID to the name to prevent this.
- It appears under some conditions (SIGTERM, etc) the shared memory files were not getting
cleaned up. Added a call to clean up the shm files under those conditions. For this user
needs to set envirable KMP_HANDLE_SIGNALS to true.

Patch by Erdner, Todd <[email protected]>

Differential Revision: https://reviews.llvm.org/D91869

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Revert "[OpenMP] Add support for Intel's umonitor/umwait"

This reverts commit 9cfad5f9c5bfd985f1bc8b0954f58013c5236e58.

[OpenMP] Add support for Intel's umonitor/umwait

Patch by tlwilmar (Terry Wilmarth)

Differential Revision: https://reviews.llvm.org/D91189

Re-land "[PowerPC] Remove QPX/A2Q BGQ/BGP CNK support"

This reverts commit bf544fa1c3cb80f24d85e84559fb11193846259f.

Fixed the typo in PPCInstrInfo.cpp.

Revert "[PowerPC] Remove QPX/A2Q BGQ/BGP CNK support"

This reverts commit adffce71538e219aab4eeb024819baa7687262ff.

This is breaking test-suite, revert while investigation.