Summary:
Some of the buildbots don't find the libraries because they don't build
for the GPU. Although it should always be there it's unclear why these
buildbots are having problemsd. LTO is only interesting on the GPU and
these tests take extra time anyway so I'm just going to disable them for
now.
First of all, `LLVM_TOOLS_INSTALL_DIR` put there breaks our NixOS
builds, because `LLVM_TOOLS_INSTALL_DIR` defined the same as
`CMAKE_INSTALL_BINDIR` becomes an *absolute* path, and then when
downstream projects try to install there too this breaks because our
builds always install to fresh directories for isolation's sake.
Second of all, note that `LLVM_TOOLS_INSTALL_DIR` stands out against the
other specially crafted `LLVM_CONFIG_*` variables substituted in
`llvm/cmake/modules/LLVMConfig.cmake.in`.
@beanz added it in d0e1c2a550 to fix a
dangling reference in `AddLLVM`, but I am suspicious of how this
variable doesn't follow the pattern.
Those other ones are carefully made to be build-time vs install-time
variables depending on which `LLVMConfig.cmake` is being generated, are
carefully made relative as appropriate, etc. etc. For my NixOS use-case
they are also fine because they are never used as downstream install
variables, only for reading not writing.
To avoid the problems I face, and restore symmetry, I deleted the
exported and arranged to have many `${project}_TOOLS_INSTALL_DIR`s.
`AddLLVM` now instead expects each project to define its own, and they
do so based on `CMAKE_INSTALL_BINDIR`. `LLVMConfig` still exports
`LLVM_TOOLS_BINARY_DIR` which is the location for the tools defined in
the usual way, matching the other remaining exported variables.
For the `AddLLVM` changes, I tried to copy the existing pattern of
internal vs non-internal or for LLVM vs for downstream function/macro
names, but it would good to confirm I did that correctly.
Reviewed By: nikic
Differential Revision: https://reviews.llvm.org/D117977
We can help optimizations by making sure we use the team state whenever
it is clear there is no thread state. To this end we introduce a new
state flag (`state::HasThreadState`) and explicit control for the
`state::ValueRAII` helpers, including a dedicated "assert equal".
Differential Revision: https://reviews.llvm.org/D130113
Our conditional writes in the runtime look like this:
```
if (active)
*ptr = value;
```
In the RAII we need to assign `ptr` which comes from a lookup call.
If a thread that is not the main thread calls lookup with the intention
to write the pointer, we'll create a new thread state. As such, we need
to avoid calling lookup for inactive threads. We used to use `nullptr`
as their `ptr` value but that can cause pessimistic reasoning. We now
use `undef` instead.
Differential Revision: https://reviews.llvm.org/D130114
We used to inline the `lookup` calls such that the runtime had "known"
access offsets when it was shipped. With the new static library build it
doesn't as the lookup is an indirection we cannot look through. This
should help us optimize the code better until we can do LTO for the
runtime again.
Differential Revision: https://reviews.llvm.org/D130111
This patch extends the `is_valid_binary` routine to also check if the
binary's architecture string matches the one parsed from the runtime.
This should allow us to only use the binary whose compute capability
matches, allowing us to support basic multi-architecture binaries for
CUDA.
Depends on D127432
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D127505
The previous path changed the linker wrapper to embed the offloading
binary format inside the target image instead. This will allow us to
more generically bundle metadata with these images, such as requires
clauses or the target architecture it was compiled for.
I wasn't sure how to handle this best, so I introduced a new type that
replaces the old `__tgt_device_image` struct that we can expand inside
the runtime library. I made the new `__tgt_device_binary` struct pretty
much the same for now. In the future we could change this struct to
pretty much be the `OffloadBinary` class in the future.
Reviewed By: JonChesterfield
Differential Revision: https://reviews.llvm.org/D127432
We previously had some logic that stopped us from building the device runtime if
there were no NVPTX architectures provided. This is incorrect because we could
have AMDGPU libraries. Even if the lists are empty we should be able to attempt
to build these and get dummy output. THis wilil make it much easier for our
tooling which expects certain libraries. If the user wishes to disable the
library entirely they should use `-DLIBOMPTARGET_BUILD_DEVICERTL_BCLIB=OFF"
Reviewed By: tianshilei1992
Differential Revision: https://reviews.llvm.org/D130266
This patch makes libomptarget depend on LLVM libraries to be built. The
reason for this is because we already have an implicit dependency on
LLVM headers for ELF identification and extraction as well as an
optional dependenly on the LLVMSupport library for time tracing
information. Furthermore, there are changes in the future that require
using more LLVM libraries, and will heavily simplify some future code as
well as open up the large amount of useful LLVM libraries to
libomptarget.
This will make "standalone" builds of `libomptarget' more difficult for
vendors wishing to ship their own. This will require a sufficiently new
version of LLVM to be installed on the system that should be picked up
by the existing handling for the implicit headers.
The things this patch changes are as follows:
- `libomptarget.so` links against LLVMSupport and LLVMObject
- `libomptarget.so` is a symbolic link to `libomptarget.so.15`
- If using a shared library build, user applications will depend on LLVM
libraries as well
- We can now use LLVM resources in Libomptarget.
Note that this patch only changes this to apply to libomptarget itself,
not the plugins. Additional patches will be necessary for that.
Reviewed By: JonChesterfield
Differential Revision: https://reviews.llvm.org/D129875
This patch makes libomptarget depend on LLVM libraries to be built. The
reason for this is because we already have an implicit dependency on
LLVM headers for ELF identification and extraction as well as an
optional dependenly on the LLVMSupport library for time tracing
information. Furthermore, there are changes in the future that require
using more LLVM libraries, and will heavily simplify some future code as
well as open up the large amount of useful LLVM libraries to
libomptarget.
This will make "standalone" builds of `libomptarget' more difficult for
vendors wishing to ship their own. This will require a sufficiently new
version of LLVM to be installed on the system that should be picked up
by the existing handling for the implicit headers.
The things this patch changes are as follows:
- `libomptarget.so` links against LLVMSupport and LLVMObject
- `libomptarget.so` is a symbolic link to `libomptarget.so.15`
- If using a shared library build, user applications will depend on LLVM
libraries as well
- We can now use LLVM resources in Libomptarget.
Note that this patch only changes this to apply to libomptarget itself,
not the plugins. Additional patches will be necessary for that.
Reviewed By: JonChesterfield
Differential Revision: https://reviews.llvm.org/D129875
This patch makes libomptarget depend on LLVM libraries to be built. The
reason for this is because we already have an implicit dependency on
LLVM headers for ELF identification and extraction as well as an
optional dependenly on the LLVMSupport library for time tracing
information. Furthermore, there are changes in the future that require
using more LLVM libraries, and will heavily simplify some future code as
well as open up the large amount of useful LLVM libraries to
libomptarget.
This will make "standalone" builds of `libomptarget' more difficult for
vendors wishing to ship their own. This will require a sufficiently new
version of LLVM to be installed on the system that should be picked up
by the existing handling for the implicit headers.
The things this patch changes are as follows:
- `libomptarget.so` links against LLVMSupport and LLVMObject
- `libomptarget.so` is a symbolic link to `libomptarget.so.15`
- If using a shared library build, user applications will depend on LLVM
libraries as well
- We can now use LLVM resources in Libomptarget.
Note that this patch only changes this to apply to libomptarget itself,
not the plugins. Additional patches will be necessary for that.
Reviewed By: JonChesterfield
Differential Revision: https://reviews.llvm.org/D129875
The device runtime uses the address space attribute to control the
placement of important constants on the GPU. The changes made in D126061
caused these to start emitting errors as they were not applied to the
type. This patch fixes the issues to make the warnings go away.
Reviewed By: ye-luo
Differential Revision: https://reviews.llvm.org/D129896
Summary:
We use a static assert to make sure that someone doesn't change the size
of an argument struct without properly updating all the other logic.
This originally only checked the size on a 64-bit system with 8-byte
pointers, causing builds on 32-bit systems to fail. This patch allows
either pointer size to work.
Fixes#56486
This patch moves the old legacy interfaces into `libomptarget` to a
separate file. These do not need to be included anywhere and are simply
provided for backwards compatibility with the ABI. This cleans up the
interface greatly.
Depends on D128817
Reviewed By: JonChesterfield
Differential Revision: https://reviews.llvm.org/D128818
The previous patch added an argument to the `__tgt_target_kernel`
runtime function which includes the tripcount used for the loop clause.
This was originally passed in via the `__kmpc_push_target_tripcount`
function. Now we move this logic to the kernel launch itself and remove
the need for the push function.
Depends on D128816
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D128817
This patch implements a unified kernel entry function that will be
targeted from both teams and non-teams clauses. We introduce a new
interface and make the old functions call in using the new one. A
following patch will include the necessary changes to Clang to call
these new functions instead.
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D128549
Libomptarget grew out of a project that was originally not in LLVM. As
we develop libomptarget this has led to an increasingly large clash
between the naming conventions used. This patch fixes most of the
variable names that did not confrom to the LLVM standard, that is
`VariableName` for variables and `functionName` for functions.
This patch was primarily done using my editor's linting messages, if
there are any issues I missed arising from the automation let me know.
Reviewed By: saiislam
Differential Revision: https://reviews.llvm.org/D128997
This patch implements omp_get_device_num() in the host and the device.
It uses the already existing getDeviceNum in the device config for the device.
And in the host it uses the omp_get_num_devices().
Two simple tests added
Differential Revision: https://reviews.llvm.org/D128347
This patch fixes the issue that P2P memcpy doesn't work. The root cause is we didn't set current context when calling the API function. In addition, a matrix to track the states of each pair of devices is also added such that we only need to query and configure the device once.
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D122764
Summary:
This patch removes a duplicated exit from the OpenMP data envrionment.
We already have an RAII method that guards this environment so it is
unnecessary.
Make libomptarget.device.a built when using -DLLVM_ENABLE_PROJECTS=openmp
Use add_custom_command.
Reviewed By: jhuber6
Differential Revision: https://reviews.llvm.org/D128130
Old LLVM installation may expose its internal omptarget CMake target when being used by find_package(LLVM) and caused issues in the CMake of libomptarget that is being built. Trap the issue early.
Reviewed By: tianshilei1992
Differential Revision: https://reviews.llvm.org/D128129
Summary:
The static linking test ensures that we can statically link offloading
programs. To create the test we used `llvm-ar`. However, this may not
exist in the user's environment. This patch changes it to use the
binutils `ar` which should exist on every system running these tests
currently. In the future we should set up the dependencies properly.
We are planning on making LTO the default compilation mode for
offloading. In order to make sure it works we should run these tests on
the test suite. AMDGPU already uses the LTO compilation path for its
linking, but in LTO mode it also links the static library late.
Performing LTO requires the static library to be built, if we make the
change this will be a hard requirement and the old bitcode library will
go away. This means users will need to use either a two-step build or a
runtimes build for libomptarget.
Reviewed By: JonChesterfield
Differential Revision: https://reviews.llvm.org/D127512
First of all, `LLVM_TOOLS_INSTALL_DIR` put there breaks our NixOS
builds, because `LLVM_TOOLS_INSTALL_DIR` defined the same as
`CMAKE_INSTALL_BINDIR` becomes an *absolute* path, and then when
downstream projects try to install there too this breaks because our
builds always install to fresh directories for isolation's sake.
Second of all, note that `LLVM_TOOLS_INSTALL_DIR` stands out against the
other specially crafted `LLVM_CONFIG_*` variables substituted in
`llvm/cmake/modules/LLVMConfig.cmake.in`.
@beanz added it in d0e1c2a550 to fix a
dangling reference in `AddLLVM`, but I am suspicious of how this
variable doesn't follow the pattern.
Those other ones are carefully made to be build-time vs install-time
variables depending on which `LLVMConfig.cmake` is being generated, are
carefully made relative as appropriate, etc. etc. For my NixOS use-case
they are also fine because they are never used as downstream install
variables, only for reading not writing.
To avoid the problems I face, and restore symmetry, I deleted the
exported and arranged to have many `${project}_TOOLS_INSTALL_DIR`s.
`AddLLVM` now instead expects each project to define its own, and they
do so based on `CMAKE_INSTALL_BINDIR`. `LLVMConfig` still exports
`LLVM_TOOLS_BINARY_DIR` which is the location for the tools defined in
the usual way, matching the other remaining exported variables.
For the `AddLLVM` changes, I tried to copy the existing pattern of
internal vs non-internal or for LLVM vs for downstream function/macro
names, but it would good to confirm I did that correctly.
Reviewed By: nikic
Differential Revision: https://reviews.llvm.org/D117977
Summary:
This test was failing because of an implicit declaration of `printf`
which isn't legal with newer C, causing it to fail. This patch just adds
the necessary header.
When we build the libomptarget device runtime library targeting bitcode,
we need special care to make sure that certain functions are not
optimized out. This is because we manually internalize and optimize
these definitions, ignoring their standard linkage semantics. When we
build with the static library, we can maintain these semantics and we do
not need these to be kept-alive. Furthermore, if they are kept-alive it
prevents them from being removed during LTO. This prevents us from
completely internalizing `IsSPMDMode` and removing several other
functions. This patch removes these for the static library target by
using a macro definition to enable them.
Reviewed By: JonChesterfield
Differential Revision: https://reviews.llvm.org/D126701
This patchs adds the arguments necessary to allocate the size of the
dynamic shared memory via the `LIBOMPTARGET_SHARED_MEMORY_SIZE`
environment variable. This patch only allocates the memory, AMDGPU has a
limitation that shared memory can only be accessed from the kernel
directly. So this will currently only work with optimizations to inline
the accessor function.
Reviewed By: JonChesterfield
Differential Revision: https://reviews.llvm.org/D125252
Without this patch, arguments to the
`llvm::OpenMPIRBuilder::AtomicOpValue` initializer are reversed.
Reviewed By: ABataev, tianshilei1992
Differential Revision: https://reviews.llvm.org/D126619
OpenMP 5.2, sec. 10.2 "teams Construct", p. 232, L9-12 restricts what
regions can be strictly nested within a `teams` construct. This patch
relaxes Clang's enforcement of this restriction in the case of nested
`atomic` constructs unless `-fno-openmp-extensions` is specified.
Cases like the following then seem to work fine with no additional
implementation changes:
```
#pragma omp target teams map(tofrom:x)
#pragma omp atomic update
x++;
```
Reviewed By: ABataev
Differential Revision: https://reviews.llvm.org/D126323
Summary:
We usually used the `OMP_LIKELY` and `OMP_UNLIKELY` macros to add branch
prediction intrinsics to help the optimizer ignore unlikely loops. This
wasn't applied to this one loop so add that in.
Summary:
This patch adds the `leaf` attribute to the `vprintf` declaration in the
OpenMP runtime. This attribute allows us to determine that the `vprintf`
function will not call any functions within the translation unit,
allowing us to deduce `norecurse` attributes on the caller.
The OpenMP device offloading library is a bitcode library and thus only
expect to build and linked with the same version of clang that was used
to create it. This somewhat copmlicates the building process as we
require the Clang that was just built to be used to create the library.
This is either done with a two-step build, where OpenMP is built with
the Clang that was just installed, or through the
`-DLLLVM_ENABLE_RUNTIMES=openmp` option. This has always been the case,
but recent changes have caused this to make it difficult to build the
rest of OpenMP. This patchs adds a check to not build the OpenMP device
runtime if the current compiler is not Clang with the same version as
the LLVM installation. This should allow users to build OpenMP as a
project using any compiler without it erroring out due to the bitcode
library, but if users require it they will need to use the above methods
to compile it.
Reviewed By: jdoerfert, tianshilei1992, ye-luo
Differential Revision: https://reviews.llvm.org/D125698
Summary:
This patch allows users to compile the static library without CUDA
installed on the system. This requires the new flag `--cuda-feature` to
indicate that we need `+ptx61` in order to compile the runtime.
This patch adds the necessary CMake configuration to build a static
library version of the device runtime, `libomptarget.devicertl.a`.
Various improvements in how we handle static libraries and generating
offloading code should allow us to treat the device library as a regular
project without needing to invoke the clang front-end directly. Here we
generate a job for each offloading architecture supported. Each
offloading architecture will be embedded into the static library and
used as-needed by the host.
This library will primarily be used to replace the bitcode library when
performing LTO. Currently, we need to manually pass in the bitcode
library which requires foreknowledge of the offloading architecture.
This approach lets us handle that in the linker wrapper instead.
Furthermore this should improve our interface to the device runtime. We
can now build it fully under a release build and have all the expected
entry points, as well as supporting debug builds.
Depends on D125265 D125256 D125260 D125314 D125563
Reviewed By: tianshilei1992
Differential Revision: https://reviews.llvm.org/D125315
We used to globally include the libomptarget include directory for all
projects. This caused some conflicts with the other files named
"Debug.h". This patch changes the cmake to include these files via the
target include instead.
Reviewed By: tianshilei1992
Differential Revision: https://reviews.llvm.org/D125563
This patche attemps to address the current warnings in the OpenMP
offloading device runtime. Previously we did not see these because we
compiled the runtime without the standard warning flags enabled.
However, these warnings are used when we now build the static library
version of this runtime. This became extremely noisy when coupled with
the fact the we compile each file roughly 32 times when all the
architectures are considered. So it would be ideal to not have all these
warnings show up when building.
Most of these errors were simply implicit switch-case fallthroughs,
which can be addressed using C++17's fallthrough attribute. Additionally
there was a volatile variable that was being casted away. This is most
likely safe to remove because we cast it away before its even used and
didn't seem to affect anything in testing.
Depends on D125260
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D125339
Currently the OpenMP offloading device runtime is only expected to be
compiled for the specific architecture it's targeting. This is
problematic if we want to make compiling the device runtime more general
via the standar `clang` driver rather than invoking the clang front-end
directly. This patch addresses this by primarily changing the declare
type to `nohost` so the host will not contain any of this code.
Additionally we forward declare the functions that are defined via
variants, otherwise these would cause problems on the host.
Reviewed By: jdoerfert, tianshilei1992
Differential Revision: https://reviews.llvm.org/D125260