llvm-project/openmp/runtime
Jonathan Peyton 6564a70415 [OpenMP][libomp] Fix register constraint for tpause and umwait
Register constraint switched to "=q" which means very specifically (from
https://gcc.gnu.org/onlinedocs/gcc/Machine-Constraints.html#Machine-Constraints)

> Any register accessible as rl. In 32-bit mode, a, b, c, and d; in 64-bit
mode, any integer register.

Older gcc versions (8.x and below) were trying to use esi or edi for the
8 bit flag variable, but it wound up displaying this error in the end:

kmp_lock.cpp: In function ‘void __kmp_spin_backoff(kmp_backoff_t*)’:
kmp_lock.cpp:2684:1: error: unsupported size for integer register
Hence the correct restriction is "=q" instead of "=r".

Fixes: https://github.com/llvm/llvm-project/issues/53309
Differential Revision: https://reviews.llvm.org/D120519
2022-03-07 14:55:49 -06:00
..
cmake [OpenMP][CMake] Ensure linking against libm for Linux 2022-03-05 20:20:28 -08:00
doc [NFC] Inclusive Language: change master to main for .chm files 2021-11-08 08:23:04 -06:00
src [OpenMP][libomp] Fix register constraint for tpause and umwait 2022-03-07 14:55:49 -06:00
test [OpenMP] libomp: implemented task priorities. 2022-03-07 22:24:18 +03:00
tools [OpenMP] libomp: add OpenMP 5.1 memory allocation routines. 2021-10-11 19:25:00 +03:00
.clang-format
.clang-tidy [OpenMP][runtime] add .clang-tidy file 2021-06-07 13:56:39 -05:00
CMakeLists.txt [OpenMP] Allow building libomp using Microsoft Visual C++ naming scheme 2021-11-11 13:11:56 -06:00
README.txt [OpenMP] RISCV64 port 2019-07-25 14:36:20 +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 README.rst in the parent directory.

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
* RISCV64 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.