llvm-project/openmp/runtime
Jonathan Peyton 072ccb7239 Set affinity to none/false in child processes
Reset affinity to none (false for proc-bind-var) so that threads in the child
processes are not bound tightly, unless the user explicitly sets this in
KMP_AFFINITY/OMP_PROC_BIND, in child processes. This can improve
performance for scripting languages which fork for parallelism like Python's
multiprocessing module.

Differential Revision: https://reviews.llvm.org/D34154

llvm-svn: 305513
2017-06-15 21:51:07 +00:00
..
cmake OpenMP version 5.0 added 2017-03-06 22:07:40 +00:00
doc Remove trailing whitespace in files in doc/ directory 2016-05-17 21:12:48 +00:00
src Set affinity to none/false in child processes 2017-06-15 21:51:07 +00:00
test OpenMP 4.5: implemented support of schedule(simd:guided) and 2017-06-05 17:17:33 +00:00
tools Support of mips & mips64 for openmprtl 2016-12-08 09:22:24 +00:00
.clang-format Add the .clang-format file which the formatting was based on 2017-05-15 16:39:42 +00:00
Build_With_CMake.txt OpenMP version 5.0 added 2017-03-06 22:07:40 +00:00
CMakeLists.txt Fix for bug https://llvm.org/bugs/show_bug.cgi?id=32456 2017-03-31 16:20:07 +00:00
README.txt Support of mips & mips64 for openmprtl 2016-12-08 09:22:24 +00:00

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.