As the codebase is now under the Apache 2.0 license with LLVM
Exceptions, and all Arm's contributions, past or future, are under that
new license, this Arm specific words in LICENSE.txt are no longer
needed.
llvm-svn: 352377
all missed!
Thanks to Alex Bradbury for pointing this out, and the fact that I never
added the intended `legacy` anchor to the developer policy. Add that
anchor too. With hope, this will cause the links to all resolve
successfully.
llvm-svn: 351731
This installs the new developer policy and moves all of the license
files across all LLVM projects in the monorepo to the new license
structure. The remaining projects will be moved independently.
Note that I've left odd formatting and other idiosyncracies of the
legacy license structure text alone to make the diff easier to read.
Critically, note that we do not in any case *remove* the old license
notice or terms, as that remains necessary until we finish the
relicensing process.
I've updated a few license files that refer to the LLVM license to
instead simply refer generically to whatever license the LLVM project is
under, basically trying to minimize confusion.
This is really the culmination of so many people. Chris led the
community discussions, drafted the policy update and organized the
multi-year string of meeting between lawyers across the community to
figure out the strategy. Numerous lawyers at companies in the community
spent their time figuring out initial answers, and then the Foundation's
lawyer Heather Meeker has done *so* much to help refine and get us ready
here. I could keep going on, but I just want to make sure everyone
realizes what a huge community effort this has been from the begining.
Differential Revision: https://reviews.llvm.org/D56897
llvm-svn: 351631
I have prepared some patches for LLVM OpenMP runtime, mostly addressing
ARMv8 support. Before I upstream them, I must address legal issues that
arose around my planned contribution. I was advised that before I send any
substantial commit, I need to make sure that LICENSE.txt file in the projects
repository contains a statement submitted by ARM, similar to the one provided
by Intel (see "a license agreement from the copyright/patent holders"). This is
the same situation as with top-level LLVM project: ARM has provided the same
statement in http://llvm.org/svn/llvm-project/llvm/trunk/lib/Target/ARM/LICENSE.TXT file.
Patch by Paul Osmialowski
Differential Revision: http://reviews.llvm.org/D19319
llvm-svn: 267446
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
Arnaud A. de Grandmaison