Summary:
Implemented by Dejan Latinovic
See https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=790735 for more more information

Reviewers: AndreyChurbanov, jlpeyton

Subscribers: openmp-commits, mgorny

Differential Revision: https://reviews.llvm.org/D26576

llvm-svn: 289032

Thanks to John Mellor-Crummey for reporting the omission.

llvm-svn: 271035

Clang no longer restricts itself to generating microtasks with a small number
of arguments, and so an assembly implementation is required to prevent hitting
the parameter limit present in the C implementation. This adds an
implementation for ppc64[le].

llvm-svn: 270821

This patch doesn't affect D19878's context.  So D19878 still cleanly applies.

llvm-svn: 270252

This patch solves 'Too many args to microtask' problem which occurs
while executing lulesh2.0.3 benchmark on AArch64.

To solve this I had to wrtite AArch64 assembly version of
__kmp_invoke_microtask() function, similar to x86 and x86_64
implementations.

Differential Revision: http://reviews.llvm.org/D19879

llvm-svn: 269399

Currently, the libomp CMake build system uses a Perl script to configure files
(tools/expand-vars.pl). This patch replaces the use of the Perl script by using
CMake's configure_file() function. The major changes include:
1. *.var has every $KMP_* variable changed to @LIBOMP_*@
2. kmp_config.h.cmake is a new file which contains all the feature macros and
   #cmakedefine lines
3. Most of the -D lines have been moved from LibompDefinitions.cmake but some
   OS specific MACROs (e.g., _GNU_SOURCE) remain.
4. All expand-vars.pl related logic is removed from the CMake files.

One important note about this change is that it breaks the old Perl+Makefile
build system because it can't create kmp_config.h properly.

Differential Review: http://reviews.llvm.org/D12211

llvm-svn: 246314

z_Linux_asm.s can use the KMP_OS_* / KMP_MIC macros instead of the predefined
compiler macro checks.  The macro logic to determine KMP_MIC is moved from
kmp_os.h to kmp_platform.h.

llvm-svn: 245602

The CMAKE_OSX_ARCHITECTURES CMake variable allows users to build
universal fat libraries that contain both i386 and x86_64 code.  These
changes allow this build by having the z_Linux_asm.s file detect the architecture
itself instead of receiving it through the build system.

Also, there was a LIBOMP_OSX_ARCHITECTURES CMake variable added to allow
people to only build libomp as a fat library and not the entire LLVM/Clang system.
http://lists.cs.uiuc.edu/pipermail/openmp-dev/2015-May/000626.html

llvm-svn: 238566

These are the actual changes in the runtime to issue OMPT-related functions. All of them are surrounded by #if OMPT_SUPPORT and can be disabled (which is the default).

llvm-svn: 236122

llvm-svn: 228727

llvm-svn: 228721

llvm-svn: 227207

llvm-svn: 225792

understand that this is not friendly, and are working to change our
internal code-development to make it easier to make development
features available more frequently and in finer (more functional)
chunks. Unfortunately we haven't got that in place yet, and unpicking
this into multiple separate check-ins would be non-trivial, so please
bear with me on this one. We should be better in the future.

Apologies over, what do we have here?

GGC 4.9 compatibility
--------------------
* We have implemented the new entrypoints used by code compiled by GCC
4.9 to implement the same functionality in gcc 4.8. Therefore code
compiled with gcc 4.9 that used to work will continue to do so.
However, there are some other new entrypoints (associated with task
cancellation) which are not implemented. Therefore user code compiled
by gcc 4.9 that uses these new features will not link against the LLVM
runtime. (It remains unclear how to handle those entrypoints, since
the GCC interface has potentially unpleasant performance implications
for join barriers even when cancellation is not used)

--- new parallel entry points ---
new entry points that aren't OpenMP 4.0 related
These are implemented fully :-
      GOMP_parallel_loop_dynamic()
      GOMP_parallel_loop_guided()
      GOMP_parallel_loop_runtime()
      GOMP_parallel_loop_static()
      GOMP_parallel_sections()
      GOMP_parallel()

--- cancellation entry points ---
Currently, these only give a runtime error if OMP_CANCELLATION is true
because our plain barriers don't check for cancellation while waiting
        GOMP_barrier_cancel()
        GOMP_cancel()
        GOMP_cancellation_point()
        GOMP_loop_end_cancel()
        GOMP_sections_end_cancel()

--- taskgroup entry points ---
These are implemented fully.
      GOMP_taskgroup_start()
      GOMP_taskgroup_end()

--- target entry points ---
These are empty (as they are in libgomp)
     GOMP_target()
     GOMP_target_data()
     GOMP_target_end_data()
     GOMP_target_update()
     GOMP_teams()

Improvements in Barriers and Fork/Join
--------------------------------------
* Barrier and fork/join code is now in its own file (which makes it
easier to understand and modify).
* Wait/release code is now templated and in its own file; suspend/resume code is also templated
* There's a new, hierarchical, barrier, which exploits the
cache-hierarchy of the Intel(r) Xeon Phi(tm) coprocessor to improve
fork/join and barrier performance.

***BEWARE*** the new source files have *not* been added to the legacy
Cmake build system. If you want to use that fixes wil be required.

Statistics Collection Code
--------------------------
* New code has been added to collect application statistics (if this
is enabled at library compile time; by default it is not). The
statistics code itself is generally useful, the lightweight timing
code uses the X86 rdtsc instruction, so will require changes for other
architectures.
The intent of this code is not for users to tune their codes but
rather 
1) For timing code-paths inside the runtime
2) For gathering general properties of OpenMP codes to focus attention
on which OpenMP features are most used. 

Nested Hot Teams
----------------
* The runtime now maintains more state to reduce the overhead of
creating and destroying inner parallel teams. This improves the
performance of code that repeatedly uses nested parallelism with the
same resource allocation. Set the new KMP_HOT_TEAMS_MAX_LEVEL
envirable to a depth to enable this (and, of course, OMP_NESTED=true
to enable nested parallelism at all).

Improved Intel(r) VTune(Tm) Amplifier support
---------------------------------------------
* The runtime provides additional information to Vtune via the
itt_notify interface to allow it to display better OpenMP specific
analyses of load-imbalance.

Support for OpenMP Composite Statements
---------------------------------------
* Implement new entrypoints required by some of the OpenMP 4.1
composite statements.

Improved ifdefs
---------------
* More separation of concepts ("Does this platform do X?") from
platforms ("Are we compiling for platform Y?"), which should simplify
future porting.


ScaleMP* contribution
---------------------
Stack padding to improve the performance in their environment where
cross-node coherency is managed at the page level.

Redesign of wait and release code
---------------------------------
The code is simplified and performance improved.

Bug Fixes
---------
    *Fixes for Windows multiple processor groups.
    *Fix Fortran module build on Linux: offload attribute added.
    *Fix entry names for distribute-parallel-loop construct to be consistent with the compiler codegen.
    *Fix an inconsistent error message for KMP_PLACE_THREADS environment variable.

llvm-svn: 219214

llvm-svn: 215093

This release use aligns with Intel(r) Composer XE 2013 SP1 Product Update 2 

New features
* The library can now be built with clang (though wiht some
  limitations since clang does not support 128 bit floats)
* Support for Vtune analysis of load imbalance
* Code contribution from Steven Noonan to build the runtime for ARM*
  architecture processors 
* First implementation of runtime API for OpenMP cancellation

Bug Fixes
* Fixed hang on Windows (only) when using KMP_BLOCKTIME=0

llvm-svn: 197914

llvm-svn: 191506