20 Commits

Author SHA1 Message Date
Alex MacLean
07ed8187ac
[OpenMP] Replace nvvm.annotation usage with kernel calling conventions (#122320)
Specifying a kernel with the `ptx_kernel` or `amdgpu_kernel` calling
convention is a more idiomatic and compile-time performant than using
the `nvvm.annoation !"kernel"` metadata.

Transition OMPIRBuilder to use calling conventions for PTX kernels and
no longer emit `nvvm.annoation`. Update OpenMPOpt to work with kernels
specified via calling convention as well as metadata. Update OpenMP
tests to use the calling conventions.
2025-01-24 16:56:10 -08:00
Johannes Doerfert
b8cbc5c02c
[OpenMP] Introduce the KernelLaunchEnvironment as implicit argument (#70401)
The KernelEnvironment is for compile time information about a kernel. It
allows the compiler to feed information to the runtime. The
KernelLaunchEnvironment is for dynamic information *per* kernel launch.
It allows the rutime to feed information to the kernel that is not
shared with other invocations of the kernel. The first use case is to
replace the globals that synchronize teams reductions with per-launch
versions. This allows concurrent teams reductions. More uses cases will
follow, e.g., per launch memory pools.

Fixes: https://github.com/llvm/llvm-project/issues/70249
2023-10-31 19:38:43 -07:00
Sergio Afonso
63ca93c7d1
[OpenMP][OMPIRBuilder] Rename IsEmbedded and IsTargetCodegen flags
This patch renames the `OpenMPIRBuilderConfig` flags to reduce confusion over
their meaning. `IsTargetCodegen` becomes `IsGPU`, whereas `IsEmbedded` becomes
`IsTargetDevice`. The `-fopenmp-is-device` compiler option is also renamed to
`-fopenmp-is-target-device` and the `omp.is_device` MLIR attribute is renamed
to `omp.is_target_device`. Getters and setters of all these renamed properties
are also updated accordingly. Many unit tests have been updated to use the new
names, but an alias for the `-fopenmp-is-device` option is created so that
external programs do not stop working after the name change.

`IsGPU` is set when the target triple is AMDGCN or NVIDIA PTX, and it is only
valid if `IsTargetDevice` is specified as well. `IsTargetDevice` is set by the
`-fopenmp-is-target-device` compiler frontend option, which is only added to
the OpenMP device invocation for offloading-enabled programs.

Differential Revision: https://reviews.llvm.org/D154591
2023-07-10 14:14:16 +01:00
Joseph Huber
8c1449a84d [OpenMP] Make kernels have protected visibility
This patch changes the kernels generated by OpenMP to have protected
visibility. This is unlikely to change anything functionally. However,
protected visibility better matches the behaviour of these GPU kernels.
We do not expect any pending shared library load to preempt these
kernels so we can specify a more restrictive visibility.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D136198
2022-10-18 16:37:28 -05:00
Joseph Huber
b9f67d44ba [OpenMP] Replace device kernel linkage with weak_odr
Currently the device kernels all have weak linkage to prevent linkage
errors on multiple defintions. However, this prevents some optimizations
from adequately analyzing them because of the nature of weak linkage.
This patch replaces the weak linkage with weak_odr linkage so we can
statically assert that multiple declarations of the same kernel will
have the same definition.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D122443
2022-03-25 11:29:15 -04:00
hyeongyu kim
1b1c8d83d3 [Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default
Turning on `enable_noundef_analysis` flag allows better codegen by removing freeze instructions.
I modified clang by renaming `enable_noundef_analysis` flag to `disable-noundef-analysis` and turning it off by default.

Test updates are made as a separate patch: D108453

Reviewed By: eugenis

Differential Revision: https://reviews.llvm.org/D105169
2022-01-16 18:54:17 +09:00
Joseph Huber
4b5c3e591d [OpenMP] Remove doing assumption propagation in the front end.
This patch removes the assumption propagation that was added in D110655
primarily to get assumption informatino on opaque call sites for
optimizations. The analysis done in D111445 allows us to do this more
intelligently in the back-end.

Depends on D111445

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D111463
2021-11-09 17:39:24 -05:00
hyeongyu kim
fd9b099906 Revert "[Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default"
This reverts commit aacfbb953eb705af2ecfeb95a6262818fa85dd92.

Revert "Fix lit test failures in CodeGenCoroutines"

This reverts commit 63fff0f5bffe20fa2c84a45a41161afa0043cb34.
2021-11-09 02:15:55 +09:00
hyeongyukim
aacfbb953e [Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default
Turning on `enable_noundef_analysis` flag allows better codegen by removing freeze instructions.
I modified clang by renaming `enable_noundef_analysis` flag to `disable-noundef-analysis` and turning it off by default.

Test updates are made as a separate patch: D108453

Reviewed By: eugenis

Differential Revision: https://reviews.llvm.org/D105169

[Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default (2)

This patch updates test files after D105169.
Autogenerated test codes are changed by `utils/update_cc_test_checks.py,` and non-autogenerated test codes are changed as follows:

(1) I wrote a python script that (partially) updates the tests using regex: {F18594904} The script is not perfect, but I believe it gives hints about which patterns are updated to have `noundef` attached.

(2) The remaining tests are updated manually.

Reviewed By: eugenis

Differential Revision: https://reviews.llvm.org/D108453

Resolve lit failures in clang after 8ca4b3e's land

Fix lit test failures in clang-ppc* and clang-x64-windows-msvc

Fix missing failures in clang-ppc64be* and retry fixing clang-x64-windows-msvc

Fix internal_clone(aarch64) inline assembly
2021-11-06 19:19:22 +09:00
Juneyoung Lee
89ad2822af Revert "[Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default"
This reverts commit 7584ef766a7219b6ee5a400637206d26e0fa98ac.
2021-11-06 15:39:19 +09:00
Juneyoung Lee
7584ef766a [Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default
Turning on `enable_noundef_analysis` flag allows better codegen by removing freeze instructions.
I modified clang by renaming `enable_noundef_analysis` flag to `disable-noundef-analysis` and turning it off by default.

Test updates are made as a separate patch: D108453

Reviewed By: eugenis

Differential Revision: https://reviews.llvm.org/D105169
2021-11-06 15:36:42 +09:00
Juneyoung Lee
f193bcc701 Revert D105169 due to the two-stage failure in ASAN
This reverts the following commits:
37ca7a795b277c20c02a218bf44052278c03344b
9aa6c72b92b6c89cc6d23b693257df9af7de2d15
705387c5074bcca36d626882462ebbc2bcc3bed4
8ca4b3ef19fe82d7ad6a6e1515317dcc01b41515
80dba72a669b5416e97a42fd2c2a7bc5a6d3f44a
2021-10-18 23:52:46 +09:00
Juneyoung Lee
8ca4b3ef19 [Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default (2)
This patch updates test files after D105169.
Autogenerated test codes are changed by `utils/update_cc_test_checks.py,` and non-autogenerated test codes are changed as follows:

(1) I wrote a python script that (partially) updates the tests using regex: {F18594904} The script is not perfect, but I believe it gives hints about which patterns are updated to have `noundef` attached.

(2) The remaining tests are updated manually.

Reviewed By: eugenis

Differential Revision: https://reviews.llvm.org/D108453
2021-10-16 12:01:41 +09:00
Joseph Huber
d12502a3ab [OpenMP] Apply OpenMP assumptions to applicable call sites
This patch adds OpenMP assumption attributes to call sites in applicable
regions. Currently this applies the caller's assumption attributes to
any calls contained within it. So, if a call occurs inside an OpenMP
assumes region to a function outside that region, we will assume that
call respects the assumptions. This is primarily useful for inline
assembly calls used heavily in the OpenMP GPU device runtime, which
allows us to then make judgements about what the ASM will do.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D110655
2021-09-29 16:08:21 -04:00
Johannes Doerfert
45e8e08492 [OpenMP] Encode omp [...] assume[...] assumptions with omp[x] prefix
Since these assumptions are coming from OpenMP it makes sense to mark
them as such in the generic IR encoding. Standardized assumptions will
be named
  omp_ASSUMPTION_NAME
and extensions will be named
  ompx_ASSUMPTION_NAME
which is the OpenMP 5.2 syntax for "extensions" of any kind.

This also matches what the OpenMP-Opt pass expects.

Summarized,
  #pragma omp [...] assume[s] no_parallelism
now generates the same IR assumption annotation as
  __attribute__((assume("omp_no_parallelism")))

Reviewed By: jhuber6

Differential Revision: https://reviews.llvm.org/D105937
2021-09-10 12:08:52 -05:00
Johannes Doerfert
e2cfbfcc0c [OpenMP] Unified entry point for SPMD & generic kernels in the device RTL
In the spirit of TRegions [0], this patch provides a simpler and uniform
interface for a kernel to set up the device runtime. The OMPIRBuilder is
used for reuse in Flang. A custom state machine will be generated in the
follow up patch.

The "surplus" threads of the "master warp" will not exit early anymore
so we need to use non-aligned barriers. The new runtime will not have an
extra warp but also require these non-aligned barriers.

[0] https://link.springer.com/chapter/10.1007/978-3-030-28596-8_11

This was in parts extracted from D59319.

Reviewed By: ABataev, JonChesterfield

Differential Revision: https://reviews.llvm.org/D101976
2021-07-10 17:53:56 -05:00
Joseph Huber
68d133a3e8 [OpenMP] Simplify GPU memory globalization
Summary:
Memory globalization is required to maintain OpenMP standard semantics for data sharing between
worker and master threads. The GPU cannot share data between its threads so must allocate global or
shared memory to store the data in. Currently this is implemented fully in the frontend using the
`__kmpc_data_sharing_push_stack` and __kmpc_data_sharing_pop_stack` functions to emulate standard
CPU stack sharing. The front-end scans the target region for variables that escape the region and
must be shared between the threads. Each variable then has a field created for it in a global record
type.

This patch replaces this functinality with a single allocation command, effectively mimicing an
alloca instruction for the variables that must be shared between the threads. This will be much
slower than the current solution, but makes it much easier to optimize as we can analyze each
variable independently and determine if it is not captured. In the future, we can replace these
calls with an `alloca` and small allocations can be pushed to shared memory.

Reviewed By: tianshilei1992

Differential Revision: https://reviews.llvm.org/D97680
2021-06-22 10:52:46 -04:00
Johannes Doerfert
2e6e4e6aee [OpenMP] Add initial support for omp [begin/end] assumes
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
2020-12-16 20:02:49 -06:00
Johannes Doerfert
1efd7a73ac Revert "[OpenMP] Add initial support for omp [begin/end] assumes"
There is a build error with gcc-5 [0], investigating now.

[0] https://reviews.llvm.org/D91980#2456526

This reverts commit a5a14cbe7f87e01882ecaa14df5d596cbf38823a.
2020-12-15 18:03:10 -06:00
Johannes Doerfert
a5a14cbe7f [OpenMP] Add initial support for omp [begin/end] assumes
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
2020-12-15 16:51:34 -06:00