Commit Graph

13 Commits

Author SHA1 Message Date
Michael Kruse 34ed3e6337 [OpenMP] Test unified shared memory tests only on systems that support it.
Add a `REQUIRES: unified_shared_memory` option to tests that use `#pragma omp requires unified_shared_memory`.

For CUDA, the feature tag is derived from LIBOMPTARGET_DEP_CUDA_ARCH which itself is derived using [[ https://cmake.org/cmake/help/latest/module/FindCUDA.html#commands | cuda_select_nvcc_arch_flags ]]. The latter determines which compute capability the GPU in the system supports. To ensure that this is the CUDA arch being used, we could also set the `-Xopenmp-target -march=` flag.
In the absence of an NVIDIA GPU, LIBOMPTARGET_DEP_CUDA_ARCH will be 35. That is, in that case we are assuming unified_shared_memory is not available. CUDA plugin testing could be disabled entirely in this case, but this currently depends on `LIBOMPTARGET_CAN_LINK_LIBCUDA OR LIBOMPTARGET_FORCE_DLOPEN_LIBCUDA`, not on whether the hardware is actually available.

For all other targets, nothing changes and we are assuming unified shared memory is available. This might need refinement if not the case.

This tries to fix the [[ http://meinersbur.de:8011/#/builders/143 | OpenMP Offloading Buildbot ]] that, although brand-new, only has a Pascal-generation (sm_61) GPU installed. Hence, tests that require unified shared memory are currently failing. I wish I had known in advance.

Reviewed By: protze.joachim, tianshilei1992

Differential Revision: https://reviews.llvm.org/D101498
2021-05-13 11:08:04 -05:00
Joachim Protze 24f836e8fd [OpenMP][libomptarget] Separate lit tests for different offloading targets (2/2)
This patch fuses the RUN lines for most libomptarget tests. The previous patch
D101315 created separate test targets for each supported offloading triple.

This patch updates the RUN lines in libomptarget tests to use a generic run
line independent of the offloading target selected for the lit instance.

In cases, where no RUN line was defined for a specific offloading target,
the corresponding target is declared as XFAIL. If it turns out that a test
actually supports the target, the XFAIL line can be removed.

Differential Revision: https://reviews.llvm.org/D101326
2021-04-27 15:54:32 +02:00
Joel E. Denny d2147b1a87 [OpenMP] Fix always,from and delete for data absent at exit
Without this patch, there's a runtime error for those map types at
exit from an "omp target data" or at "omp target exit data", but the
spec says the list item should be ignored.

This patch tests that fix in data_absent_at_exit.c, and it also
improves other testing for data that is not fully present at exit.

Reviewed By: grokos, RaviNarayanaswamy

Differential Revision: https://reviews.llvm.org/D96999
2021-02-19 11:09:26 -05:00
Joseph Huber 7a5a74ea96 [OpenMP] Always emit debug messages that indicate offloading failure
Summary:

This patch changes the libomptarget runtime to always emit debug messages that
occur before offloading failure. The goal is to provide users with information
about why their application failed in the target region rather than a single
failure message. This is only done in regions that precede offloading failure
so this should not impact runtime performance. if the debug environment
variable is set then the message is forwarded to the debug output as usual.

A new environment variable was added for future use but does nothing in this
current patch. LIBOMPTARGET_INFO will be used to report runtime information to
the user if requrested, such as grid size, SPMD usage, or data mapping. It will
take an integer indicating the level of information verbosity and a value of 0
will disable it.

Reviewers: jdoerfort

Subscribers: guansong sstefan1 yaxunl ye-luo

Tags: #OpenMP

Differential Revision: https://reviews.llvm.org/D86483
2020-08-26 19:30:41 -04:00
Joel E. Denny 41b1aefecb [OpenMP] Fix `present` diagnostic for array extension
For example, without this patch, the following fails as expected with
or without the `present` modifier, but the `present` modifier doesn't
produce its usual diagnostic:

```
 #pragma omp target data map(alloc: arr[0:2])
 {
   #pragma omp target map(present, tofrom: arr[0:100]) // not fully present
   ;
 }
```

Reviewed By: grokos, vzakhari

Differential Revision: https://reviews.llvm.org/D85320
2020-08-05 16:51:24 -04:00
Joel E. Denny 5ab43989c3 [OpenMP] Fix `omp target update` for array extension
OpenMP TR8 sec. 2.15.6 "target update Construct", p. 183, L3-4 states:

> If the corresponding list item is not present in the device data
> environment and there is no present modifier in the clause, then no
> assignment occurs to or from the original list item.

L10-11 states:

> If a present modifier appears in the clause and the corresponding
> list item is not present in the device data environment then an
> error occurs and the program termintates.

(OpenMP 5.0 also has the first passage but without mention of the
present modifier of course.)

In both passages, I assume "is not present" includes the case of
partially but not entirely present.  However, without this patch, the
target update directive misbehaves in this case both with and without
the present modifier.  For example:

```
 #pragma omp target enter data map(to:arr[0:3])
 #pragma omp target update to(arr[0:5]) // might fail on data transfer
 #pragma omp target update to(present:arr[0:5]) // might fail on data transfer
```

The problem is that `DeviceTy::getTgtPtrBegin` does not return a null
pointer in that case, so `target_data_update` sees the data as fully
present, and the data transfer then might fail depending on the target
device.  However, without the present modifier, there should never be
a failure.  Moreover, with the present modifier, there should always
be a failure, and the diagnostic should mention the present modifier.

This patch fixes `DeviceTy::getTgtPtrBegin` to return null when
`target_data_update` is the caller.  I'm wondering if it should do the
same for more callers.

Reviewed By: grokos, jdoerfert

Differential Revision: https://reviews.llvm.org/D85246
2020-08-05 10:03:31 -04:00
Joel E. Denny 002d61db2b [OpenMP] Fix `present` for exit from `omp target data`
Without this patch, the following example fails but shouldn't
according to OpenMP TR8:

```
 #pragma omp target enter data map(alloc:i)
 #pragma omp target data map(present, alloc: i)
 {
   #pragma omp target exit data map(delete:i)
 } // fails presence check here
```

OpenMP TR8 sec. 2.22.7.1 "map Clause", p. 321, L23-26 states:

> If the map clause appears on a target, target data, target enter
> data or target exit data construct with a present map-type-modifier
> then on entry to the region if the corresponding list item does not
> appear in the device data environment an error occurs and the
> program terminates.

There is no corresponding statement about the exit from a region.
Thus, the `present` modifier should:

1. Check for presence upon entry into any region, including a `target
   exit data` region.  This behavior is already implemented correctly.

2. Should not check for presence upon exit from any region, including
   a `target` or `target data` region.  Without this patch, this
   behavior is not implemented correctly, breaking the above example.

In the case of `target data`, this patch fixes the latter behavior by
removing the `present` modifier from the map types Clang generates for
the runtime call at the end of the region.

In the case of `target`, we have not found a valid OpenMP program for
which such a fix would matter.  It appears that, if a program can
guarantee that data is present at the beginning of a `target` region
so that there's no error there, that data is also guaranteed to be
present at the end.  This patch adds a comment to the runtime to
document this case.

Reviewed By: grokos, RaviNarayanaswamy, ABataev

Differential Revision: https://reviews.llvm.org/D84422
2020-08-05 10:03:31 -04:00
Joel E. Denny cee52dd026 [OpenMP] Implement TR8 `present` motion modifier in runtime (2/2)
This patch implements OpenMP runtime support for the OpenMP TR8
`present` motion modifier for `omp target update` directives.  The
previous patch in this series implements Clang front end support.

Reviewed By: grokos

Differential Revision: https://reviews.llvm.org/D84712
2020-07-29 12:18:50 -04:00
Joel E. Denny 65564e5eaf Revert "[OpenMP] Implement TR8 `present` motion modifier in runtime (2/2)"
This reverts commit 2cb926a447.

It depends on 3c3faae497, which is being
reverted.
2020-07-28 20:30:05 -04:00
Joel E. Denny 2cb926a447 [OpenMP] Implement TR8 `present` motion modifier in runtime (2/2)
This patch implements OpenMP runtime support for the OpenMP TR8
`present` motion modifier for `omp target update` directives.  The
previous patch in this series implements Clang front end support.

Reviewed By: grokos

Differential Revision: https://reviews.llvm.org/D84712
2020-07-28 19:15:18 -04:00
Joel E. Denny 708752b2f6 [OpenMP] Implement TR8 `present` map type modifier in runtime (2/2)
This implements OpenMP runtime support for the OpenMP TR8 `present`
map type modifier.  The previous patch in this series implements Clang
front end support.  See that patch summary for behaviors that are not
yet supported.

Reviewed By: grokos, jdoerfert

Differential Revision: https://reviews.llvm.org/D83062
2020-07-22 14:04:58 -04:00
Joel E. Denny fc247c8f3c Revert "[OpenMP] Implement TR8 `present` map type modifier in runtime (2/2)"
This reverts commit 45b8f7ec35.

It attempts to use debug macros `DPxMOD` and `DPxPTR` in release
builds.  Will fix and reapply later.
2020-07-22 11:22:08 -04:00
Joel E. Denny 45b8f7ec35 [OpenMP] Implement TR8 `present` map type modifier in runtime (2/2)
This implements OpenMP runtime support for the OpenMP TR8 `present`
map type modifier.  The previous patch in this series implements Clang
front end support.  See that patch summary for behaviors that are not
yet supported.

Reviewed By: grokos, jdoerfert

Differential Revision: https://reviews.llvm.org/D83062
2020-07-22 10:15:32 -04:00