forked from OSchip/llvm-project
d0ef19ef9b
Traditionally, the library had a weak symbol for ompt_start_tool() that served as fallback and disabled OMPT if called. Tools could provide their own version and replace the default implementation to register callbacks and lookup functions. This mechanism has worked reasonably well on Linux systems where this interface was initially developed. On Darwin / Mac OS X the situation is a bit more complicated and the weak symbol doesn't work out-of-the-box. In my tests, the library with the tool needed to link against the OpenMP runtime to make the process work. This would effectively mean that a tool needed to choose a runtime library whereas one design goal of the interface was to allow tools that are agnostic of the runtime. The solution is to use dlsym() with the argument RTLD_DEFAULT so that static implementations of ompt_start_tool() are found in the main executable. This works because the linker on Mac OS X includes all symbols of an executable in the global symbol table by default. To use the same code path on Linux, the application would need to be built with -Wl,--export-dynamic. To avoid this restriction, we continue to use weak symbols on Linux systems as before. Finally this patch extends the existing test to cover all possible ways of initializing the tool as described by the standard. It also fixes ompt_finalize() to not call omp_get_thread_num() when the library is shut down which resulted in hangs on Darwin. The changes have been tested on Linux to make sure that it passes the current tests as well as the newly extended one. Differential Revision: https://reviews.llvm.org/D39801 llvm-svn: 317980 |
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| .. | ||
| cmake | ||
| doc | ||
| src | ||
| test | ||
| tools | ||
| .clang-format | ||
| Build_With_CMake.txt | ||
| CMakeLists.txt | ||
| README.txt | ||
README.txt
README for the LLVM* OpenMP* Runtime Library
============================================
How to Build Documentation
==========================
The main documentation is in Doxygen* format, and this distribution
should come with pre-built PDF documentation in doc/Reference.pdf.
However, an HTML version can be built by executing:
% doxygen doc/doxygen/config
in the runtime directory.
That will produce HTML documentation in the doc/doxygen/generated
directory, which can be accessed by pointing a web browser at the
index.html file there.
If you don't have Doxygen installed, you can download it from
www.doxygen.org.
How to Build the LLVM* OpenMP* Runtime Library
==============================================
In-tree build:
$ cd where-you-want-to-live
Check out openmp into llvm/projects
$ cd where-you-want-to-build
$ mkdir build && cd build
$ cmake path/to/llvm -DCMAKE_C_COMPILER=<C compiler> -DCMAKE_CXX_COMPILER=<C++ compiler>
$ make omp
Out-of-tree build:
$ cd where-you-want-to-live
Check out openmp
$ cd where-you-want-to-live/openmp/runtime
$ mkdir build && cd build
$ cmake path/to/openmp -DCMAKE_C_COMPILER=<C compiler> -DCMAKE_CXX_COMPILER=<C++ compiler>
$ make
For details about building, please look at Build_With_CMake.txt
Architectures Supported
=======================
* IA-32 architecture
* Intel(R) 64 architecture
* Intel(R) Many Integrated Core Architecture
* ARM* architecture
* Aarch64 (64-bit ARM) architecture
* IBM(R) Power architecture (big endian)
* IBM(R) Power architecture (little endian)
* MIPS and MIPS64 architecture
Supported RTL Build Configurations
==================================
Supported Architectures: IA-32 architecture, Intel(R) 64, and
Intel(R) Many Integrated Core Architecture
----------------------------------------------
| icc/icl | gcc | clang |
--------------|---------------|----------------------------|
| Linux* OS | Yes(1,5) | Yes(2,4) | Yes(4,6,7) |
| FreeBSD* | No | No | Yes(4,6,7,8) |
| OS X* | Yes(1,3,4) | No | Yes(4,6,7) |
| Windows* OS | Yes(1,4) | No | No |
------------------------------------------------------------
(1) On IA-32 architecture and Intel(R) 64, icc/icl versions 12.x are
supported (12.1 is recommended).
(2) GCC* version 4.7 is supported.
(3) For icc on OS X*, OS X* version 10.5.8 is supported.
(4) Intel(R) Many Integrated Core Architecture not supported.
(5) On Intel(R) Many Integrated Core Architecture, icc/icl versions 13.0
or later are required.
(6) Clang* version 3.3 is supported.
(7) Clang* currently does not offer a software-implemented 128 bit extended
precision type. Thus, all entry points reliant on this type are removed
from the library and cannot be called in the user program. The following
functions are not available:
__kmpc_atomic_cmplx16_*
__kmpc_atomic_float16_*
__kmpc_atomic_*_fp
(8) Community contribution provided AS IS, not tested by Intel.
Supported Architectures: IBM(R) Power 7 and Power 8
-----------------------------
| gcc | clang |
--------------|------------|--------------|
| Linux* OS | Yes(1,2) | Yes(3,4) |
-------------------------------------------
(1) On Power 7, gcc version 4.8.2 is supported.
(2) On Power 8, gcc version 4.8.2 is supported.
(3) On Power 7, clang version 3.7 is supported.
(4) On Power 8, clang version 3.7 is supported.
Front-end Compilers that work with this RTL
===========================================
The following compilers are known to do compatible code generation for
this RTL: clang (from the OpenMP development branch at
http://clang-omp.github.io/ ), Intel compilers, GCC. See the documentation
for more details.
-----------------------------------------------------------------------
Notices
=======
*Other names and brands may be claimed as the property of others.