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diff --git a/libgomp/libgomp.info b/libgomp/libgomp.info new file mode 100644 index 000000000..3624aa6b5 --- /dev/null +++ b/libgomp/libgomp.info @@ -0,0 +1,2513 @@ +This is libgomp.info, produced by makeinfo version 4.13 from +/home/jakub/gcc-4.6.4/gcc-4.6.4/libgomp/libgomp.texi. + +Copyright (C) 2006, 2007, 2008, 2010, 2011 Free Software Foundation, +Inc. + + Permission is granted to copy, distribute and/or modify this document +under the terms of the GNU Free Documentation License, Version 1.3 or +any later version published by the Free Software Foundation; with the +Invariant Sections being "Funding Free Software", the Front-Cover texts +being (a) (see below), and with the Back-Cover Texts being (b) (see +below). A copy of the license is included in the section entitled "GNU +Free Documentation License". + + (a) The FSF's Front-Cover Text is: + + A GNU Manual + + (b) The FSF's Back-Cover Text is: + + You have freedom to copy and modify this GNU Manual, like GNU +software. Copies published by the Free Software Foundation raise +funds for GNU development. + +INFO-DIR-SECTION GNU Libraries +START-INFO-DIR-ENTRY +* libgomp: (libgomp). GNU OpenMP runtime library +END-INFO-DIR-ENTRY + + This manual documents the GNU implementation of the OpenMP API for +multi-platform shared-memory parallel programming in C/C++ and Fortran. + + Published by the Free Software Foundation 51 Franklin Street, Fifth +Floor Boston, MA 02110-1301 USA + + Copyright (C) 2006, 2007, 2008, 2010, 2011 Free Software Foundation, +Inc. + + Permission is granted to copy, distribute and/or modify this document +under the terms of the GNU Free Documentation License, Version 1.3 or +any later version published by the Free Software Foundation; with the +Invariant Sections being "Funding Free Software", the Front-Cover texts +being (a) (see below), and with the Back-Cover Texts being (b) (see +below). A copy of the license is included in the section entitled "GNU +Free Documentation License". + + (a) The FSF's Front-Cover Text is: + + A GNU Manual + + (b) The FSF's Back-Cover Text is: + + You have freedom to copy and modify this GNU Manual, like GNU +software. Copies published by the Free Software Foundation raise +funds for GNU development. + + +File: libgomp.info, Node: Top, Next: Enabling OpenMP, Up: (dir) + +Introduction +************ + +This manual documents the usage of libgomp, the GNU implementation of +the OpenMP (http://www.openmp.org) Application Programming Interface +(API) for multi-platform shared-memory parallel programming in C/C++ +and Fortran. + +* Menu: + +* Enabling OpenMP:: How to enable OpenMP for your applications. +* Runtime Library Routines:: The OpenMP runtime application programming + interface. +* Environment Variables:: Influencing runtime behavior with environment + variables. +* The libgomp ABI:: Notes on the external ABI presented by libgomp. +* Reporting Bugs:: How to report bugs in GNU OpenMP. +* Copying:: GNU general public license says + how you can copy and share libgomp. +* GNU Free Documentation License:: + How you can copy and share this manual. +* Funding:: How to help assure continued work for free + software. +* Index:: Index of this documentation. + + +File: libgomp.info, Node: Enabling OpenMP, Next: Runtime Library Routines, Prev: Top, Up: Top + +1 Enabling OpenMP +***************** + +To activate the OpenMP extensions for C/C++ and Fortran, the +compile-time flag `-fopenmp' must be specified. This enables the OpenMP +directive `#pragma omp' in C/C++ and `!$omp' directives in free form, +`c$omp', `*$omp' and `!$omp' directives in fixed form, `!$' conditional +compilation sentinels in free form and `c$', `*$' and `!$' sentinels in +fixed form, for Fortran. The flag also arranges for automatic linking +of the OpenMP runtime library (*note Runtime Library Routines::). + + A complete description of all OpenMP directives accepted may be +found in the OpenMP Application Program Interface +(http://www.openmp.org) manual, version 3.0. + + +File: libgomp.info, Node: Runtime Library Routines, Next: Environment Variables, Prev: Enabling OpenMP, Up: Top + +2 Runtime Library Routines +************************** + +The runtime routines described here are defined by section 3 of the +OpenMP specifications in version 3.0. The routines are structured in +following three parts: + + Control threads, processors and the parallel environment. + +* Menu: + +* omp_get_active_level:: Number of active parallel regions +* omp_get_ancestor_thread_num:: Ancestor thread ID +* omp_get_dynamic:: Dynamic teams setting +* omp_get_level:: Number of parallel regions +* omp_get_max_active_levels:: Maximum number of active regions +* omp_get_max_threads:: Maximum number of threads of parallel region +* omp_get_nested:: Nested parallel regions +* omp_get_num_procs:: Number of processors online +* omp_get_num_threads:: Size of the active team +* omp_get_schedule:: Obtain the runtime scheduling method +* omp_get_team_size:: Number of threads in a team +* omp_get_thread_limit:: Maximum number of threads +* omp_get_thread_num:: Current thread ID +* omp_in_parallel:: Whether a parallel region is active +* omp_set_dynamic:: Enable/disable dynamic teams +* omp_set_max_active_levels:: Limits the number of active parallel regions +* omp_set_nested:: Enable/disable nested parallel regions +* omp_set_num_threads:: Set upper team size limit +* omp_set_schedule:: Set the runtime scheduling method + + Initialize, set, test, unset and destroy simple and nested locks. + +* Menu: + +* omp_init_lock:: Initialize simple lock +* omp_set_lock:: Wait for and set simple lock +* omp_test_lock:: Test and set simple lock if available +* omp_unset_lock:: Unset simple lock +* omp_destroy_lock:: Destroy simple lock +* omp_init_nest_lock:: Initialize nested lock +* omp_set_nest_lock:: Wait for and set simple lock +* omp_test_nest_lock:: Test and set nested lock if available +* omp_unset_nest_lock:: Unset nested lock +* omp_destroy_nest_lock:: Destroy nested lock + + Portable, thread-based, wall clock timer. + +* Menu: + +* omp_get_wtick:: Get timer precision. +* omp_get_wtime:: Elapsed wall clock time. + + +File: libgomp.info, Node: omp_get_active_level, Next: omp_get_ancestor_thread_num, Up: Runtime Library Routines + +2.1 `omp_get_active_level' - Number of parallel regions +======================================================= + +_Description_: + This function returns the nesting level for the active parallel + blocks, which enclose the calling call. + +_C/C++_ + _Prototype_: `int omp_get_active_level(void);' + +_Fortran_: + _Interface_: `integer function omp_get_active_level()' + +_See also_: + *note omp_get_level::, *note omp_get_max_active_levels::, *note + omp_set_max_active_levels:: + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), section + 3.2.19. + + +File: libgomp.info, Node: omp_get_ancestor_thread_num, Next: omp_get_dynamic, Prev: omp_get_active_level, Up: Runtime Library Routines + +2.2 `omp_get_ancestor_thread_num' - Ancestor thread ID +====================================================== + +_Description_: + This function returns the thread identification number for the + given nesting level of the current thread. For values of LEVEL + outside zero to `omp_get_level' -1 is returned; if LEVEL is + `omp_get_level' the result is identical to `omp_get_thread_num'. + +_C/C++_ + _Prototype_: `int omp_get_ancestor_thread_num(int level);' + +_Fortran_: + _Interface_: `integer function omp_get_ancestor_thread_num(level)' + `integer level' + +_See also_: + *note omp_get_level::, *note omp_get_thread_num::, *note + omp_get_team_size:: + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), section + 3.2.17. + + +File: libgomp.info, Node: omp_get_dynamic, Next: omp_get_level, Prev: omp_get_ancestor_thread_num, Up: Runtime Library Routines + +2.3 `omp_get_dynamic' - Dynamic teams setting +============================================= + +_Description_: + This function returns `true' if enabled, `false' otherwise. Here, + `true' and `false' represent their language-specific counterparts. + + The dynamic team setting may be initialized at startup by the + `OMP_DYNAMIC' environment variable or at runtime using + `omp_set_dynamic'. If undefined, dynamic adjustment is disabled by + default. + +_C/C++_: + _Prototype_: `int omp_get_dynamic(void);' + +_Fortran_: + _Interface_: `logical function omp_get_dynamic()' + +_See also_: + *note omp_set_dynamic::, *note OMP_DYNAMIC:: + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), section 3.2.8. + + +File: libgomp.info, Node: omp_get_level, Next: omp_get_max_active_levels, Prev: omp_get_dynamic, Up: Runtime Library Routines + +2.4 `omp_get_level' - Obtain the current nesting level +====================================================== + +_Description_: + This function returns the nesting level for the parallel blocks, + which enclose the calling call. + +_C/C++_ + _Prototype_: `int omp_get_level(void);' + +_Fortran_: + _Interface_: `integer function omp_level()' + +_See also_: + *note omp_get_active_level:: + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), section + 3.2.16. + + +File: libgomp.info, Node: omp_get_max_active_levels, Next: omp_get_max_threads, Prev: omp_get_level, Up: Runtime Library Routines + +2.5 `omp_get_max_active_levels' - Maximum number of active regions +================================================================== + +_Description_: + This function obtains the maximum allowed number of nested, active + parallel regions. + +_C/C++_ + _Prototype_: `int omp_get_max_active_levels(void);' + +_Fortran_: + _Interface_: `integer function omp_get_max_active_levels()' + +_See also_: + *note omp_set_max_active_levels::, *note omp_get_active_level:: + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), section + 3.2.14. + + +File: libgomp.info, Node: omp_get_max_threads, Next: omp_get_nested, Prev: omp_get_max_active_levels, Up: Runtime Library Routines + +2.6 `omp_get_max_threads' - Maximum number of threads of parallel region +======================================================================== + +_Description_: + Return the maximum number of threads used for the current parallel + region that does not use the clause `num_threads'. + +_C/C++_: + _Prototype_: `int omp_get_max_threads(void);' + +_Fortran_: + _Interface_: `integer function omp_get_max_threads()' + +_See also_: + *note omp_set_num_threads::, *note omp_set_dynamic::, *note + omp_get_thread_limit:: + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), section 3.2.3. + + +File: libgomp.info, Node: omp_get_nested, Next: omp_get_num_procs, Prev: omp_get_max_threads, Up: Runtime Library Routines + +2.7 `omp_get_nested' - Nested parallel regions +============================================== + +_Description_: + This function returns `true' if nested parallel regions are + enabled, `false' otherwise. Here, `true' and `false' represent + their language-specific counterparts. + + Nested parallel regions may be initialized at startup by the + `OMP_NESTED' environment variable or at runtime using + `omp_set_nested'. If undefined, nested parallel regions are + disabled by default. + +_C/C++_: + _Prototype_: `int omp_get_nested(void);' + +_Fortran_: + _Interface_: `logical function omp_get_nested()' + +_See also_: + *note omp_set_nested::, *note OMP_NESTED:: + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), section + 3.2.10. + + +File: libgomp.info, Node: omp_get_num_procs, Next: omp_get_num_threads, Prev: omp_get_nested, Up: Runtime Library Routines + +2.8 `omp_get_num_procs' - Number of processors online +===================================================== + +_Description_: + Returns the number of processors online. + +_C/C++_: + _Prototype_: `int omp_get_num_procs(void);' + +_Fortran_: + _Interface_: `integer function omp_get_num_procs()' + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), section 3.2.5. + + +File: libgomp.info, Node: omp_get_num_threads, Next: omp_get_schedule, Prev: omp_get_num_procs, Up: Runtime Library Routines + +2.9 `omp_get_num_threads' - Size of the active team +=================================================== + +_Description_: + Returns the number of threads in the current team. In a sequential + section of the program `omp_get_num_threads' returns 1. + + The default team size may be initialized at startup by the + `OMP_NUM_THREADS' environment variable. At runtime, the size of + the current team may be set either by the `NUM_THREADS' clause or + by `omp_set_num_threads'. If none of the above were used to define + a specific value and `OMP_DYNAMIC' is disabled, one thread per CPU + online is used. + +_C/C++_: + _Prototype_: `int omp_get_num_threads(void);' + +_Fortran_: + _Interface_: `integer function omp_get_num_threads()' + +_See also_: + *note omp_get_max_threads::, *note omp_set_num_threads::, *note + OMP_NUM_THREADS:: + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), section 3.2.2. + + +File: libgomp.info, Node: omp_get_schedule, Next: omp_get_team_size, Prev: omp_get_num_threads, Up: Runtime Library Routines + +2.10 `omp_get_schedule' - Obtain the runtime scheduling method +============================================================== + +_Description_: + Obtain the runtime scheduling method. The KIND argument will be + set to the value `omp_sched_static', `omp_sched_dynamic', + `omp_sched_guided' or `omp_sched_auto'. The second argument, + MODIFIER, is set to the chunk size. + +_C/C++_ + _Prototype_: `omp_schedule(omp_sched_t *kind, int *modifier);' + +_Fortran_: + _Interface_: `subroutine omp_schedule(kind, modifier)' + `integer(kind=omp_sched_kind) kind' + `integer modifier' + +_See also_: + *note omp_set_schedule::, *note OMP_SCHEDULE:: + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), section + 3.2.12. + + +File: libgomp.info, Node: omp_get_team_size, Next: omp_get_thread_limit, Prev: omp_get_schedule, Up: Runtime Library Routines + +2.11 `omp_get_team_size' - Number of threads in a team +====================================================== + +_Description_: + This function returns the number of threads in a thread team to + which either the current thread or its ancestor belongs. For + values of LEVEL outside zero to `omp_get_level', -1 is returned; + if LEVEL is zero, 1 is returned, and for `omp_get_level', the + result is identical to `omp_get_num_threads'. + +_C/C++_: + _Prototype_: `int omp_get_team_size(int level);' + +_Fortran_: + _Interface_: `integer function omp_get_team_size(level)' + `integer level' + +_See also_: + *note omp_get_num_threads::, *note omp_get_level::, *note + omp_get_ancestor_thread_num:: + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), section + 3.2.18. + + +File: libgomp.info, Node: omp_get_thread_limit, Next: omp_get_thread_num, Prev: omp_get_team_size, Up: Runtime Library Routines + +2.12 `omp_get_thread_limit' - Maximum number of threads +======================================================= + +_Description_: + Return the maximum number of threads of the program. + +_C/C++_: + _Prototype_: `int omp_get_thread_limit(void);' + +_Fortran_: + _Interface_: `integer function omp_get_thread_limit()' + +_See also_: + *note omp_get_max_threads::, *note OMP_THREAD_LIMIT:: + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), section + 3.2.13. + + +File: libgomp.info, Node: omp_get_thread_num, Next: omp_in_parallel, Prev: omp_get_thread_limit, Up: Runtime Library Routines + +2.13 `omp_get_thread_num' - Current thread ID +============================================= + +_Description_: + Returns a unique thread identification number within the current + team. In a sequential parts of the program, `omp_get_thread_num' + always returns 0. In parallel regions the return value varies from + 0 to `omp_get_num_threads'-1 inclusive. The return value of the + master thread of a team is always 0. + +_C/C++_: + _Prototype_: `int omp_get_thread_num(void);' + +_Fortran_: + _Interface_: `integer function omp_get_thread_num()' + +_See also_: + *note omp_get_num_threads::, *note omp_get_ancestor_thread_num:: + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), section 3.2.4. + + +File: libgomp.info, Node: omp_in_parallel, Next: omp_set_dynamic, Prev: omp_get_thread_num, Up: Runtime Library Routines + +2.14 `omp_in_parallel' - Whether a parallel region is active +============================================================ + +_Description_: + This function returns `true' if currently running in parallel, + `false' otherwise. Here, `true' and `false' represent their + language-specific counterparts. + +_C/C++_: + _Prototype_: `int omp_in_parallel(void);' + +_Fortran_: + _Interface_: `logical function omp_in_parallel()' + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), section 3.2.6. + + +File: libgomp.info, Node: omp_set_dynamic, Next: omp_set_max_active_levels, Prev: omp_in_parallel, Up: Runtime Library Routines + +2.15 `omp_set_dynamic' - Enable/disable dynamic teams +===================================================== + +_Description_: + Enable or disable the dynamic adjustment of the number of threads + within a team. The function takes the language-specific equivalent + of `true' and `false', where `true' enables dynamic adjustment of + team sizes and `false' disables it. + +_C/C++_: + _Prototype_: `void omp_set_dynamic(int set);' + +_Fortran_: + _Interface_: `subroutine omp_set_dynamic(set)' + `logical, intent(in) :: set' + +_See also_: + *note OMP_DYNAMIC::, *note omp_get_dynamic:: + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), section 3.2.7. + + +File: libgomp.info, Node: omp_set_max_active_levels, Next: omp_set_nested, Prev: omp_set_dynamic, Up: Runtime Library Routines + +2.16 `omp_set_max_active_levels' - Limits the number of active parallel regions +=============================================================================== + +_Description_: + This function limits the maximum allowed number of nested, active + parallel regions. + +_C/C++_ + _Prototype_: `void omp_set_max_active_levels(int max_levels);' + +_Fortran_: + _Interface_: `subroutine omp_set_max_active_levels(max_levels)' + `integer max_levels' + +_See also_: + *note omp_get_max_active_levels::, *note omp_get_active_level:: + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), section + 3.2.14. + + +File: libgomp.info, Node: omp_set_nested, Next: omp_set_num_threads, Prev: omp_set_max_active_levels, Up: Runtime Library Routines + +2.17 `omp_set_nested' - Enable/disable nested parallel regions +============================================================== + +_Description_: + Enable or disable nested parallel regions, i.e., whether team + members are allowed to create new teams. The function takes the + language-specific equivalent of `true' and `false', where `true' + enables dynamic adjustment of team sizes and `false' disables it. + +_C/C++_: + _Prototype_: `void omp_set_nested(int set);' + +_Fortran_: + _Interface_: `subroutine omp_set_nested(set)' + `logical, intent(in) :: set' + +_See also_: + *note OMP_NESTED::, *note omp_get_nested:: + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), section 3.2.9. + + +File: libgomp.info, Node: omp_set_num_threads, Next: omp_set_schedule, Prev: omp_set_nested, Up: Runtime Library Routines + +2.18 `omp_set_num_threads' - Set upper team size limit +====================================================== + +_Description_: + Specifies the number of threads used by default in subsequent + parallel sections, if those do not specify a `num_threads' clause. + The argument of `omp_set_num_threads' shall be a positive integer. + +_C/C++_: + _Prototype_: `void omp_set_num_threads(int n);' + +_Fortran_: + _Interface_: `subroutine omp_set_num_threads(n)' + `integer, intent(in) :: n' + +_See also_: + *note OMP_NUM_THREADS::, *note omp_get_num_threads::, *note + omp_get_max_threads:: + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), section 3.2.1. + + +File: libgomp.info, Node: omp_set_schedule, Next: omp_init_lock, Prev: omp_set_num_threads, Up: Runtime Library Routines + +2.19 `omp_set_schedule' - Set the runtime scheduling method +=========================================================== + +_Description_: + Sets the runtime scheduling method. The KIND argument can have the + value `omp_sched_static', `omp_sched_dynamic', `omp_sched_guided' + or `omp_sched_auto'. Except for `omp_sched_auto', the chunk size + is set to the value of MODIFIER if positive, or to the default + value if zero or negative. For `omp_sched_auto' the MODIFIER + argument is ignored. + +_C/C++_ + _Prototype_: `int omp_set_schedule(omp_sched_t *kind, int + *modifier);' + +_Fortran_: + _Interface_: `subroutine omp_set_schedule(kind, modifier)' + `integer(kind=omp_sched_kind) kind' + `integer modifier' + +_See also_: + *note omp_get_schedule:: *note OMP_SCHEDULE:: + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), section + 3.2.11. + + +File: libgomp.info, Node: omp_init_lock, Next: omp_set_lock, Prev: omp_set_schedule, Up: Runtime Library Routines + +2.20 `omp_init_lock' - Initialize simple lock +============================================= + +_Description_: + Initialize a simple lock. After initialization, the lock is in an + unlocked state. + +_C/C++_: + _Prototype_: `void omp_init_lock(omp_lock_t *lock);' + +_Fortran_: + _Interface_: `subroutine omp_init_lock(lock)' + `integer(omp_lock_kind), intent(out) :: lock' + +_See also_: + *note omp_destroy_lock:: + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), section 3.3.1. + + +File: libgomp.info, Node: omp_set_lock, Next: omp_test_lock, Prev: omp_init_lock, Up: Runtime Library Routines + +2.21 `omp_set_lock' - Wait for and set simple lock +================================================== + +_Description_: + Before setting a simple lock, the lock variable must be + initialized by `omp_init_lock'. The calling thread is blocked + until the lock is available. If the lock is already held by the + current thread, a deadlock occurs. + +_C/C++_: + _Prototype_: `void omp_set_lock(omp_lock_t *lock);' + +_Fortran_: + _Interface_: `subroutine omp_set_lock(lock)' + `integer(omp_lock_kind), intent(inout) :: lock' + +_See also_: + *note omp_init_lock::, *note omp_test_lock::, *note + omp_unset_lock:: + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), section 3.3.3. + + +File: libgomp.info, Node: omp_test_lock, Next: omp_unset_lock, Prev: omp_set_lock, Up: Runtime Library Routines + +2.22 `omp_test_lock' - Test and set simple lock if available +============================================================ + +_Description_: + Before setting a simple lock, the lock variable must be + initialized by `omp_init_lock'. Contrary to `omp_set_lock', + `omp_test_lock' does not block if the lock is not available. This + function returns `true' upon success, `false' otherwise. Here, + `true' and `false' represent their language-specific counterparts. + +_C/C++_: + _Prototype_: `int omp_test_lock(omp_lock_t *lock);' + +_Fortran_: + _Interface_: `subroutine omp_test_lock(lock)' + `logical(omp_logical_kind) :: omp_test_lock' + `integer(omp_lock_kind), intent(inout) :: lock' + +_See also_: + *note omp_init_lock::, *note omp_set_lock::, *note omp_set_lock:: + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), section 3.3.5. + + +File: libgomp.info, Node: omp_unset_lock, Next: omp_destroy_lock, Prev: omp_test_lock, Up: Runtime Library Routines + +2.23 `omp_unset_lock' - Unset simple lock +========================================= + +_Description_: + A simple lock about to be unset must have been locked by + `omp_set_lock' or `omp_test_lock' before. In addition, the lock + must be held by the thread calling `omp_unset_lock'. Then, the + lock becomes unlocked. If one or more threads attempted to set the + lock before, one of them is chosen to, again, set the lock for + itself. + +_C/C++_: + _Prototype_: `void omp_unset_lock(omp_lock_t *lock);' + +_Fortran_: + _Interface_: `subroutine omp_unset_lock(lock)' + `integer(omp_lock_kind), intent(inout) :: lock' + +_See also_: + *note omp_set_lock::, *note omp_test_lock:: + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), section 3.3.4. + + +File: libgomp.info, Node: omp_destroy_lock, Next: omp_init_nest_lock, Prev: omp_unset_lock, Up: Runtime Library Routines + +2.24 `omp_destroy_lock' - Destroy simple lock +============================================= + +_Description_: + Destroy a simple lock. In order to be destroyed, a simple lock + must be in the unlocked state. + +_C/C++_: + _Prototype_: `void omp_destroy_lock(omp_lock_t *lock);' + +_Fortran_: + _Interface_: `subroutine omp_destroy_lock(lock)' + `integer(omp_lock_kind), intent(inout) :: lock' + +_See also_: + *note omp_init_lock:: + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), section 3.3.2. + + +File: libgomp.info, Node: omp_init_nest_lock, Next: omp_set_nest_lock, Prev: omp_destroy_lock, Up: Runtime Library Routines + +2.25 `omp_init_nest_lock' - Initialize nested lock +================================================== + +_Description_: + Initialize a nested lock. After initialization, the lock is in an + unlocked state and the nesting count is set to zero. + +_C/C++_: + _Prototype_: `void omp_init_nest_lock(omp_nest_lock_t *lock);' + +_Fortran_: + _Interface_: `subroutine omp_init_nest_lock(lock)' + `integer(omp_nest_lock_kind), intent(out) :: lock' + +_See also_: + *note omp_destroy_nest_lock:: + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), section 3.3.1. + + +File: libgomp.info, Node: omp_set_nest_lock, Next: omp_test_nest_lock, Prev: omp_init_nest_lock, Up: Runtime Library Routines + +2.26 `omp_set_nest_lock' - Wait for and set nested lock +======================================================= + +_Description_: + Before setting a nested lock, the lock variable must be + initialized by `omp_init_nest_lock'. The calling thread is blocked + until the lock is available. If the lock is already held by the + current thread, the nesting count for the lock in incremented. + +_C/C++_: + _Prototype_: `void omp_set_nest_lock(omp_nest_lock_t *lock);' + +_Fortran_: + _Interface_: `subroutine omp_set_nest_lock(lock)' + `integer(omp_nest_lock_kind), intent(inout) :: lock' + +_See also_: + *note omp_init_nest_lock::, *note omp_unset_nest_lock:: + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), section 3.3.3. + + +File: libgomp.info, Node: omp_test_nest_lock, Next: omp_unset_nest_lock, Prev: omp_set_nest_lock, Up: Runtime Library Routines + +2.27 `omp_test_nest_lock' - Test and set nested lock if available +================================================================= + +_Description_: + Before setting a nested lock, the lock variable must be + initialized by `omp_init_nest_lock'. Contrary to + `omp_set_nest_lock', `omp_test_nest_lock' does not block if the + lock is not available. If the lock is already held by the current + thread, the new nesting count is returned. Otherwise, the return + value equals zero. + +_C/C++_: + _Prototype_: `int omp_test_nest_lock(omp_nest_lock_t *lock);' + +_Fortran_: + _Interface_: `integer function omp_test_nest_lock(lock)' + `integer(omp_integer_kind) :: omp_test_nest_lock' + `integer(omp_nest_lock_kind), intent(inout) :: lock' + +_See also_: + *note omp_init_lock::, *note omp_set_lock::, *note omp_set_lock:: + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), section 3.3.5. + + +File: libgomp.info, Node: omp_unset_nest_lock, Next: omp_destroy_nest_lock, Prev: omp_test_nest_lock, Up: Runtime Library Routines + +2.28 `omp_unset_nest_lock' - Unset nested lock +============================================== + +_Description_: + A nested lock about to be unset must have been locked by + `omp_set_nested_lock' or `omp_test_nested_lock' before. In + addition, the lock must be held by the thread calling + `omp_unset_nested_lock'. If the nesting count drops to zero, the + lock becomes unlocked. If one ore more threads attempted to set + the lock before, one of them is chosen to, again, set the lock for + itself. + +_C/C++_: + _Prototype_: `void omp_unset_nest_lock(omp_nest_lock_t *lock);' + +_Fortran_: + _Interface_: `subroutine omp_unset_nest_lock(lock)' + `integer(omp_nest_lock_kind), intent(inout) :: lock' + +_See also_: + *note omp_set_nest_lock:: + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), section 3.3.4. + + +File: libgomp.info, Node: omp_destroy_nest_lock, Next: omp_get_wtick, Prev: omp_unset_nest_lock, Up: Runtime Library Routines + +2.29 `omp_destroy_nest_lock' - Destroy nested lock +================================================== + +_Description_: + Destroy a nested lock. In order to be destroyed, a nested lock + must be in the unlocked state and its nesting count must equal + zero. + +_C/C++_: + _Prototype_: `void omp_destroy_nest_lock(omp_nest_lock_t *);' + +_Fortran_: + _Interface_: `subroutine omp_destroy_nest_lock(lock)' + `integer(omp_nest_lock_kind), intent(inout) :: lock' + +_See also_: + *note omp_init_lock:: + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), section 3.3.2. + + +File: libgomp.info, Node: omp_get_wtick, Next: omp_get_wtime, Prev: omp_destroy_nest_lock, Up: Runtime Library Routines + +2.30 `omp_get_wtick' - Get timer precision +========================================== + +_Description_: + Gets the timer precision, i.e., the number of seconds between two + successive clock ticks. + +_C/C++_: + _Prototype_: `double omp_get_wtick(void);' + +_Fortran_: + _Interface_: `double precision function omp_get_wtick()' + +_See also_: + *note omp_get_wtime:: + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), section 3.4.2. + + +File: libgomp.info, Node: omp_get_wtime, Prev: omp_get_wtick, Up: Runtime Library Routines + +2.31 `omp_get_wtime' - Elapsed wall clock time +============================================== + +_Description_: + Elapsed wall clock time in seconds. The time is measured per + thread, no guarantee can be made that two distinct threads measure + the same time. Time is measured from some "time in the past", + which is an arbitrary time guaranteed not to change during the + execution of the program. + +_C/C++_: + _Prototype_: `double omp_get_wtime(void);' + +_Fortran_: + _Interface_: `double precision function omp_get_wtime()' + +_See also_: + *note omp_get_wtick:: + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), section 3.4.1. + + +File: libgomp.info, Node: Environment Variables, Next: The libgomp ABI, Prev: Runtime Library Routines, Up: Top + +3 Environment Variables +*********************** + +The variables `OMP_DYNAMIC', `OMP_MAX_ACTIVE_LEVELS', `OMP_NESTED', +`OMP_NUM_THREADS', `OMP_SCHEDULE', `OMP_STACKSIZE',`OMP_THREAD_LIMIT' +and `OMP_WAIT_POLICY' are defined by section 4 of the OpenMP +specifications in version 3.0, while `GOMP_CPU_AFFINITY' and +`GOMP_STACKSIZE' are GNU extensions. + +* Menu: + +* OMP_DYNAMIC:: Dynamic adjustment of threads +* OMP_MAX_ACTIVE_LEVELS:: Set the maximum number of nested parallel regions +* OMP_NESTED:: Nested parallel regions +* OMP_NUM_THREADS:: Specifies the number of threads to use +* OMP_STACKSIZE:: Set default thread stack size +* OMP_SCHEDULE:: How threads are scheduled +* OMP_THREAD_LIMIT:: Set the maximum number of threads +* OMP_WAIT_POLICY:: How waiting threads are handled +* GOMP_CPU_AFFINITY:: Bind threads to specific CPUs +* GOMP_STACKSIZE:: Set default thread stack size + + +File: libgomp.info, Node: OMP_DYNAMIC, Next: OMP_MAX_ACTIVE_LEVELS, Up: Environment Variables + +3.1 `OMP_DYNAMIC' - Dynamic adjustment of threads +================================================= + +_Description_: + Enable or disable the dynamic adjustment of the number of threads + within a team. The value of this environment variable shall be + `TRUE' or `FALSE'. If undefined, dynamic adjustment is disabled by + default. + +_See also_: + *note omp_set_dynamic:: + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), section 4.3 + + +File: libgomp.info, Node: OMP_MAX_ACTIVE_LEVELS, Next: OMP_NESTED, Prev: OMP_DYNAMIC, Up: Environment Variables + +3.2 `OMP_MAX_ACTIVE_LEVELS' - Set the maximum number of nested parallel regions +=============================================================================== + +_Description_: + Specifies the initial value for the maximum number of nested + parallel regions. The value of this variable shall be positive + integer. If undefined, the number of active levels is unlimited. + +_See also_: + *note omp_set_max_active_levels:: + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), section 4.7 + + +File: libgomp.info, Node: OMP_NESTED, Next: OMP_NUM_THREADS, Prev: OMP_MAX_ACTIVE_LEVELS, Up: Environment Variables + +3.3 `OMP_NESTED' - Nested parallel regions +========================================== + +_Description_: + Enable or disable nested parallel regions, i.e., whether team + members are allowed to create new teams. The value of this + environment variable shall be `TRUE' or `FALSE'. If undefined, + nested parallel regions are disabled by default. + +_See also_: + *note omp_set_nested:: + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), section 4.4 + + +File: libgomp.info, Node: OMP_NUM_THREADS, Next: OMP_STACKSIZE, Prev: OMP_NESTED, Up: Environment Variables + +3.4 `OMP_NUM_THREADS' - Specifies the number of threads to use +============================================================== + +_Description_: + Specifies the default number of threads to use in parallel + regions. The value of this variable shall be a positive integer. + If undefined one thread per CPU is used. + +_See also_: + *note omp_set_num_threads:: + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), section 4.2 + + +File: libgomp.info, Node: OMP_SCHEDULE, Next: OMP_THREAD_LIMIT, Prev: OMP_STACKSIZE, Up: Environment Variables + +3.5 `OMP_SCHEDULE' - How threads are scheduled +============================================== + +_Description_: + Allows to specify `schedule type' and `chunk size'. The value of + the variable shall have the form: `type[,chunk]' where `type' is + one of `static', `dynamic', `guided' or `auto' The optional + `chunk' size shall be a positive integer. If undefined, dynamic + scheduling and a chunk size of 1 is used. + +_See also_: + *note omp_set_schedule:: + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), sections + 2.5.1 and 4.1 + + +File: libgomp.info, Node: OMP_STACKSIZE, Next: OMP_SCHEDULE, Prev: OMP_NUM_THREADS, Up: Environment Variables + +3.6 `OMP_STACKSIZE' - Set default thread stack size +=================================================== + +_Description_: + Set the default thread stack size in kilobytes, unless the number + is suffixed by `B', `K', `M' or `G', in which case the size is, + respectively, in bytes, kilobytes, megabytes or gigabytes. This is + different from `pthread_attr_setstacksize' which gets the number + of bytes as an argument. If the stacksize cannot be set due to + system constraints, an error is reported and the initial stacksize + is left unchanged. If undefined, the stack size is system + dependent. + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), sections 4.5 + + +File: libgomp.info, Node: OMP_THREAD_LIMIT, Next: OMP_WAIT_POLICY, Prev: OMP_SCHEDULE, Up: Environment Variables + +3.7 `OMP_THREAD_LIMIT' - Set the maximum number of threads +========================================================== + +_Description_: + Specifies the number of threads to use for the whole program. The + value of this variable shall be a positive integer. If undefined, + the number of threads is not limited. + +_See also_: + *note OMP_NUM_THREADS:: *note omp_get_thread_limit:: + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), section 4.8 + + +File: libgomp.info, Node: OMP_WAIT_POLICY, Next: GOMP_CPU_AFFINITY, Prev: OMP_THREAD_LIMIT, Up: Environment Variables + +3.8 `OMP_WAIT_POLICY' - How waiting threads are handled +======================================================= + +_Description_: + Specifies whether waiting threads should be active or passive. If + the value is `PASSIVE', waiting threads should not consume CPU + power while waiting; while the value is `ACTIVE' specifies that + they should. + +_Reference_: + OpenMP specifications v3.0 (http://www.openmp.org/), sections 4.6 + + +File: libgomp.info, Node: GOMP_CPU_AFFINITY, Next: GOMP_STACKSIZE, Prev: OMP_WAIT_POLICY, Up: Environment Variables + +3.9 `GOMP_CPU_AFFINITY' - Bind threads to specific CPUs +======================================================= + +_Description_: + Binds threads to specific CPUs. The variable should contain a + space-separated or comma-separated list of CPUs. This list may + contain different kinds of entries: either single CPU numbers in + any order, a range of CPUs (M-N) or a range with some stride + (M-N:S). CPU numbers are zero based. For example, + `GOMP_CPU_AFFINITY="0 3 1-2 4-15:2"' will bind the initial thread + to CPU 0, the second to CPU 3, the third to CPU 1, the fourth to + CPU 2, the fifth to CPU 4, the sixth through tenth to CPUs 6, 8, + 10, 12, and 14 respectively and then start assigning back from the + beginning of the list. `GOMP_CPU_AFFINITY=0' binds all threads to + CPU 0. + + There is no GNU OpenMP library routine to determine whether a CPU + affinity specification is in effect. As a workaround, + language-specific library functions, e.g., `getenv' in C or + `GET_ENVIRONMENT_VARIABLE' in Fortran, may be used to query the + setting of the `GOMP_CPU_AFFINITY' environment variable. A defined + CPU affinity on startup cannot be changed or disabled during the + runtime of the application. + + If this environment variable is omitted, the host system will + handle the assignment of threads to CPUs. + + +File: libgomp.info, Node: GOMP_STACKSIZE, Prev: GOMP_CPU_AFFINITY, Up: Environment Variables + +3.10 `GOMP_STACKSIZE' - Set default thread stack size +===================================================== + +_Description_: + Set the default thread stack size in kilobytes. This is different + from `pthread_attr_setstacksize' which gets the number of bytes as + an argument. If the stacksize cannot be set due to system + constraints, an error is reported and the initial stacksize is + left unchanged. If undefined, the stack size is system dependent. + +_See also_: + *note OMP_STACKSIZE:: + +_Reference_: + GCC Patches Mailinglist + (http://gcc.gnu.org/ml/gcc-patches/2006-06/msg00493.html), GCC + Patches Mailinglist + (http://gcc.gnu.org/ml/gcc-patches/2006-06/msg00496.html) + + +File: libgomp.info, Node: The libgomp ABI, Next: Reporting Bugs, Prev: Environment Variables, Up: Top + +4 The libgomp ABI +***************** + +The following sections present notes on the external ABI as presented +by libgomp. Only maintainers should need them. + +* Menu: + +* Implementing MASTER construct:: +* Implementing CRITICAL construct:: +* Implementing ATOMIC construct:: +* Implementing FLUSH construct:: +* Implementing BARRIER construct:: +* Implementing THREADPRIVATE construct:: +* Implementing PRIVATE clause:: +* Implementing FIRSTPRIVATE LASTPRIVATE COPYIN and COPYPRIVATE clauses:: +* Implementing REDUCTION clause:: +* Implementing PARALLEL construct:: +* Implementing FOR construct:: +* Implementing ORDERED construct:: +* Implementing SECTIONS construct:: +* Implementing SINGLE construct:: + + +File: libgomp.info, Node: Implementing MASTER construct, Next: Implementing CRITICAL construct, Up: The libgomp ABI + +4.1 Implementing MASTER construct +================================= + + if (omp_get_thread_num () == 0) + block + + Alternately, we generate two copies of the parallel subfunction and +only include this in the version run by the master thread. Surely this +is not worthwhile though... + + +File: libgomp.info, Node: Implementing CRITICAL construct, Next: Implementing ATOMIC construct, Prev: Implementing MASTER construct, Up: The libgomp ABI + +4.2 Implementing CRITICAL construct +=================================== + +Without a specified name, + + void GOMP_critical_start (void); + void GOMP_critical_end (void); + + so that we don't get COPY relocations from libgomp to the main +application. + + With a specified name, use omp_set_lock and omp_unset_lock with name +being transformed into a variable declared like + + omp_lock_t gomp_critical_user_<name> __attribute__((common)) + + Ideally the ABI would specify that all zero is a valid unlocked +state, and so we wouldn't need to initialize this at startup. + + +File: libgomp.info, Node: Implementing ATOMIC construct, Next: Implementing FLUSH construct, Prev: Implementing CRITICAL construct, Up: The libgomp ABI + +4.3 Implementing ATOMIC construct +================================= + +The target should implement the `__sync' builtins. + + Failing that we could add + + void GOMP_atomic_enter (void) + void GOMP_atomic_exit (void) + + which reuses the regular lock code, but with yet another lock object +private to the library. + + +File: libgomp.info, Node: Implementing FLUSH construct, Next: Implementing BARRIER construct, Prev: Implementing ATOMIC construct, Up: The libgomp ABI + +4.4 Implementing FLUSH construct +================================ + +Expands to the `__sync_synchronize' builtin. + + +File: libgomp.info, Node: Implementing BARRIER construct, Next: Implementing THREADPRIVATE construct, Prev: Implementing FLUSH construct, Up: The libgomp ABI + +4.5 Implementing BARRIER construct +================================== + + void GOMP_barrier (void) + + +File: libgomp.info, Node: Implementing THREADPRIVATE construct, Next: Implementing PRIVATE clause, Prev: Implementing BARRIER construct, Up: The libgomp ABI + +4.6 Implementing THREADPRIVATE construct +======================================== + +In _most_ cases we can map this directly to `__thread'. Except that +OMP allows constructors for C++ objects. We can either refuse to +support this (how often is it used?) or we can implement something akin +to .ctors. + + Even more ideally, this ctor feature is handled by extensions to the +main pthreads library. Failing that, we can have a set of entry points +to register ctor functions to be called. + + +File: libgomp.info, Node: Implementing PRIVATE clause, Next: Implementing FIRSTPRIVATE LASTPRIVATE COPYIN and COPYPRIVATE clauses, Prev: Implementing THREADPRIVATE construct, Up: The libgomp ABI + +4.7 Implementing PRIVATE clause +=============================== + +In association with a PARALLEL, or within the lexical extent of a +PARALLEL block, the variable becomes a local variable in the parallel +subfunction. + + In association with FOR or SECTIONS blocks, create a new automatic +variable within the current function. This preserves the semantic of +new variable creation. + + +File: libgomp.info, Node: Implementing FIRSTPRIVATE LASTPRIVATE COPYIN and COPYPRIVATE clauses, Next: Implementing REDUCTION clause, Prev: Implementing PRIVATE clause, Up: The libgomp ABI + +4.8 Implementing FIRSTPRIVATE LASTPRIVATE COPYIN and COPYPRIVATE clauses +======================================================================== + +This seems simple enough for PARALLEL blocks. Create a private struct +for communicating between the parent and subfunction. In the parent, +copy in values for scalar and "small" structs; copy in addresses for +others TREE_ADDRESSABLE types. In the subfunction, copy the value into +the local variable. + + It is not clear what to do with bare FOR or SECTION blocks. The +only thing I can figure is that we do something like: + + #pragma omp for firstprivate(x) lastprivate(y) + for (int i = 0; i < n; ++i) + body; + + which becomes + + { + int x = x, y; + + // for stuff + + if (i == n) + y = y; + } + + where the "x=x" and "y=y" assignments actually have different uids +for the two variables, i.e. not something you could write directly in +C. Presumably this only makes sense if the "outer" x and y are global +variables. + + COPYPRIVATE would work the same way, except the structure broadcast +would have to happen via SINGLE machinery instead. + + +File: libgomp.info, Node: Implementing REDUCTION clause, Next: Implementing PARALLEL construct, Prev: Implementing FIRSTPRIVATE LASTPRIVATE COPYIN and COPYPRIVATE clauses, Up: The libgomp ABI + +4.9 Implementing REDUCTION clause +================================= + +The private struct mentioned in the previous section should have a +pointer to an array of the type of the variable, indexed by the +thread's TEAM_ID. The thread stores its final value into the array, +and after the barrier, the master thread iterates over the array to +collect the values. + + +File: libgomp.info, Node: Implementing PARALLEL construct, Next: Implementing FOR construct, Prev: Implementing REDUCTION clause, Up: The libgomp ABI + +4.10 Implementing PARALLEL construct +==================================== + + #pragma omp parallel + { + body; + } + + becomes + + void subfunction (void *data) + { + use data; + body; + } + + setup data; + GOMP_parallel_start (subfunction, &data, num_threads); + subfunction (&data); + GOMP_parallel_end (); + + void GOMP_parallel_start (void (*fn)(void *), void *data, unsigned num_threads) + + The FN argument is the subfunction to be run in parallel. + + The DATA argument is a pointer to a structure used to communicate +data in and out of the subfunction, as discussed above with respect to +FIRSTPRIVATE et al. + + The NUM_THREADS argument is 1 if an IF clause is present and false, +or the value of the NUM_THREADS clause, if present, or 0. + + The function needs to create the appropriate number of threads +and/or launch them from the dock. It needs to create the team +structure and assign team ids. + + void GOMP_parallel_end (void) + + Tears down the team and returns us to the previous +`omp_in_parallel()' state. + + +File: libgomp.info, Node: Implementing FOR construct, Next: Implementing ORDERED construct, Prev: Implementing PARALLEL construct, Up: The libgomp ABI + +4.11 Implementing FOR construct +=============================== + + #pragma omp parallel for + for (i = lb; i <= ub; i++) + body; + + becomes + + void subfunction (void *data) + { + long _s0, _e0; + while (GOMP_loop_static_next (&_s0, &_e0)) + { + long _e1 = _e0, i; + for (i = _s0; i < _e1; i++) + body; + } + GOMP_loop_end_nowait (); + } + + GOMP_parallel_loop_static (subfunction, NULL, 0, lb, ub+1, 1, 0); + subfunction (NULL); + GOMP_parallel_end (); + + #pragma omp for schedule(runtime) + for (i = 0; i < n; i++) + body; + + becomes + + { + long i, _s0, _e0; + if (GOMP_loop_runtime_start (0, n, 1, &_s0, &_e0)) + do { + long _e1 = _e0; + for (i = _s0, i < _e0; i++) + body; + } while (GOMP_loop_runtime_next (&_s0, _&e0)); + GOMP_loop_end (); + } + + Note that while it looks like there is trickiness to propagating a +non-constant STEP, there isn't really. We're explicitly allowed to +evaluate it as many times as we want, and any variables involved should +automatically be handled as PRIVATE or SHARED like any other variables. +So the expression should remain evaluable in the subfunction. We can +also pull it into a local variable if we like, but since its supposed +to remain unchanged, we can also not if we like. + + If we have SCHEDULE(STATIC), and no ORDERED, then we ought to be +able to get away with no work-sharing context at all, since we can +simply perform the arithmetic directly in each thread to divide up the +iterations. Which would mean that we wouldn't need to call any of +these routines. + + There are separate routines for handling loops with an ORDERED +clause. Bookkeeping for that is non-trivial... + + +File: libgomp.info, Node: Implementing ORDERED construct, Next: Implementing SECTIONS construct, Prev: Implementing FOR construct, Up: The libgomp ABI + +4.12 Implementing ORDERED construct +=================================== + + void GOMP_ordered_start (void) + void GOMP_ordered_end (void) + + +File: libgomp.info, Node: Implementing SECTIONS construct, Next: Implementing SINGLE construct, Prev: Implementing ORDERED construct, Up: The libgomp ABI + +4.13 Implementing SECTIONS construct +==================================== + +A block as + + #pragma omp sections + { + #pragma omp section + stmt1; + #pragma omp section + stmt2; + #pragma omp section + stmt3; + } + + becomes + + for (i = GOMP_sections_start (3); i != 0; i = GOMP_sections_next ()) + switch (i) + { + case 1: + stmt1; + break; + case 2: + stmt2; + break; + case 3: + stmt3; + break; + } + GOMP_barrier (); + + +File: libgomp.info, Node: Implementing SINGLE construct, Prev: Implementing SECTIONS construct, Up: The libgomp ABI + +4.14 Implementing SINGLE construct +================================== + +A block like + + #pragma omp single + { + body; + } + + becomes + + if (GOMP_single_start ()) + body; + GOMP_barrier (); + + while + + #pragma omp single copyprivate(x) + body; + + becomes + + datap = GOMP_single_copy_start (); + if (datap == NULL) + { + body; + data.x = x; + GOMP_single_copy_end (&data); + } + else + x = datap->x; + GOMP_barrier (); + + +File: libgomp.info, Node: Reporting Bugs, Next: Copying, Prev: The libgomp ABI, Up: Top + +5 Reporting Bugs +**************** + +Bugs in the GNU OpenMP implementation should be reported via bugzilla +(http://gcc.gnu.org/bugzilla/). For all cases, please add "openmp" to +the keywords field in the bug report. + + +File: libgomp.info, Node: Copying, Next: GNU Free Documentation License, Prev: Reporting Bugs, Up: Top + +GNU GENERAL PUBLIC LICENSE +************************** + + Version 2, June 1991 + + Copyright (C) 1989, 1991 Free Software Foundation, Inc. + 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA + + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + +Preamble +======== + +The licenses for most software are designed to take away your freedom +to share and change it. By contrast, the GNU General Public License is +intended to guarantee your freedom to share and change free +software--to make sure the software is free for all its users. This +General Public License applies to most of the Free Software +Foundation's software and to any other program whose authors commit to +using it. (Some other Free Software Foundation software is covered by +the GNU Library General Public License instead.) You can apply it to +your programs, too. + + When we speak of free software, we are referring to freedom, not +price. Our General Public Licenses are designed to make sure that you +have the freedom to distribute copies of free software (and charge for +this service if you wish), that you receive source code or can get it +if you want it, that you can change the software or use pieces of it in +new free programs; and that you know you can do these things. + + To protect your rights, we need to make restrictions that forbid +anyone to deny you these rights or to ask you to surrender the rights. +These restrictions translate to certain responsibilities for you if you +distribute copies of the software, or if you modify it. + + For example, if you distribute copies of such a program, whether +gratis or for a fee, you must give the recipients all the rights that +you have. You must make sure that they, too, receive or can get the +source code. And you must show them these terms so they know their +rights. + + We protect your rights with two steps: (1) copyright the software, +and (2) offer you this license which gives you legal permission to copy, +distribute and/or modify the software. + + Also, for each author's protection and ours, we want to make certain +that everyone understands that there is no warranty for this free +software. If the software is modified by someone else and passed on, we +want its recipients to know that what they have is not the original, so +that any problems introduced by others will not reflect on the original +authors' reputations. + + Finally, any free program is threatened constantly by software +patents. We wish to avoid the danger that redistributors of a free +program will individually obtain patent licenses, in effect making the +program proprietary. To prevent this, we have made it clear that any +patent must be licensed for everyone's free use or not licensed at all. + + The precise terms and conditions for copying, distribution and +modification follow. + + TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION + 0. This License applies to any program or other work which contains a + notice placed by the copyright holder saying it may be distributed + under the terms of this General Public License. The "Program", + below, refers to any such program or work, and a "work based on + the Program" means either the Program or any derivative work under + copyright law: that is to say, a work containing the Program or a + portion of it, either verbatim or with modifications and/or + translated into another language. (Hereinafter, translation is + included without limitation in the term "modification".) Each + licensee is addressed as "you". + + Activities other than copying, distribution and modification are + not covered by this License; they are outside its scope. The act + of running the Program is not restricted, and the output from the + Program is covered only if its contents constitute a work based on + the Program (independent of having been made by running the + Program). Whether that is true depends on what the Program does. + + 1. You may copy and distribute verbatim copies of the Program's + source code as you receive it, in any medium, provided that you + conspicuously and appropriately publish on each copy an appropriate + copyright notice and disclaimer of warranty; keep intact all the + notices that refer to this License and to the absence of any + warranty; and give any other recipients of the Program a copy of + this License along with the Program. + + You may charge a fee for the physical act of transferring a copy, + and you may at your option offer warranty protection in exchange + for a fee. + + 2. You may modify your copy or copies of the Program or any portion + of it, thus forming a work based on the Program, and copy and + distribute such modifications or work under the terms of Section 1 + above, provided that you also meet all of these conditions: + + a. You must cause the modified files to carry prominent notices + stating that you changed the files and the date of any change. + + b. You must cause any work that you distribute or publish, that + in whole or in part contains or is derived from the Program + or any part thereof, to be licensed as a whole at no charge + to all third parties under the terms of this License. + + c. If the modified program normally reads commands interactively + when run, you must cause it, when started running for such + interactive use in the most ordinary way, to print or display + an announcement including an appropriate copyright notice and + a notice that there is no warranty (or else, saying that you + provide a warranty) and that users may redistribute the + program under these conditions, and telling the user how to + view a copy of this License. (Exception: if the Program + itself is interactive but does not normally print such an + announcement, your work based on the Program is not required + to print an announcement.) + + These requirements apply to the modified work as a whole. If + identifiable sections of that work are not derived from the + Program, and can be reasonably considered independent and separate + works in themselves, then this License, and its terms, do not + apply to those sections when you distribute them as separate + works. But when you distribute the same sections as part of a + whole which is a work based on the Program, the distribution of + the whole must be on the terms of this License, whose permissions + for other licensees extend to the entire whole, and thus to each + and every part regardless of who wrote it. + + Thus, it is not the intent of this section to claim rights or + contest your rights to work written entirely by you; rather, the + intent is to exercise the right to control the distribution of + derivative or collective works based on the Program. + + In addition, mere aggregation of another work not based on the + Program with the Program (or with a work based on the Program) on + a volume of a storage or distribution medium does not bring the + other work under the scope of this License. + + 3. You may copy and distribute the Program (or a work based on it, + under Section 2) in object code or executable form under the terms + of Sections 1 and 2 above provided that you also do one of the + following: + + a. Accompany it with the complete corresponding machine-readable + source code, which must be distributed under the terms of + Sections 1 and 2 above on a medium customarily used for + software interchange; or, + + b. Accompany it with a written offer, valid for at least three + years, to give any third party, for a charge no more than your + cost of physically performing source distribution, a complete + machine-readable copy of the corresponding source code, to be + distributed under the terms of Sections 1 and 2 above on a + medium customarily used for software interchange; or, + + c. Accompany it with the information you received as to the offer + to distribute corresponding source code. (This alternative is + allowed only for noncommercial distribution and only if you + received the program in object code or executable form with + such an offer, in accord with Subsection b above.) + + The source code for a work means the preferred form of the work for + making modifications to it. For an executable work, complete + source code means all the source code for all modules it contains, + plus any associated interface definition files, plus the scripts + used to control compilation and installation of the executable. + However, as a special exception, the source code distributed need + not include anything that is normally distributed (in either + source or binary form) with the major components (compiler, + kernel, and so on) of the operating system on which the executable + runs, unless that component itself accompanies the executable. + + If distribution of executable or object code is made by offering + access to copy from a designated place, then offering equivalent + access to copy the source code from the same place counts as + distribution of the source code, even though third parties are not + compelled to copy the source along with the object code. + + 4. You may not copy, modify, sublicense, or distribute the Program + except as expressly provided under this License. Any attempt + otherwise to copy, modify, sublicense or distribute the Program is + void, and will automatically terminate your rights under this + License. However, parties who have received copies, or rights, + from you under this License will not have their licenses + terminated so long as such parties remain in full compliance. + + 5. You are not required to accept this License, since you have not + signed it. However, nothing else grants you permission to modify + or distribute the Program or its derivative works. These actions + are prohibited by law if you do not accept this License. + Therefore, by modifying or distributing the Program (or any work + based on the Program), you indicate your acceptance of this + License to do so, and all its terms and conditions for copying, + distributing or modifying the Program or works based on it. + + 6. Each time you redistribute the Program (or any work based on the + Program), the recipient automatically receives a license from the + original licensor to copy, distribute or modify the Program + subject to these terms and conditions. You may not impose any + further restrictions on the recipients' exercise of the rights + granted herein. You are not responsible for enforcing compliance + by third parties to this License. + + 7. If, as a consequence of a court judgment or allegation of patent + infringement or for any other reason (not limited to patent + issues), conditions are imposed on you (whether by court order, + agreement or otherwise) that contradict the conditions of this + License, they do not excuse you from the conditions of this + License. If you cannot distribute so as to satisfy simultaneously + your obligations under this License and any other pertinent + obligations, then as a consequence you may not distribute the + Program at all. For example, if a patent license would not permit + royalty-free redistribution of the Program by all those who + receive copies directly or indirectly through you, then the only + way you could satisfy both it and this License would be to refrain + entirely from distribution of the Program. + + If any portion of this section is held invalid or unenforceable + under any particular circumstance, the balance of the section is + intended to apply and the section as a whole is intended to apply + in other circumstances. + + It is not the purpose of this section to induce you to infringe any + patents or other property right claims or to contest validity of + any such claims; this section has the sole purpose of protecting + the integrity of the free software distribution system, which is + implemented by public license practices. Many people have made + generous contributions to the wide range of software distributed + through that system in reliance on consistent application of that + system; it is up to the author/donor to decide if he or she is + willing to distribute software through any other system and a + licensee cannot impose that choice. + + This section is intended to make thoroughly clear what is believed + to be a consequence of the rest of this License. + + 8. If the distribution and/or use of the Program is restricted in + certain countries either by patents or by copyrighted interfaces, + the original copyright holder who places the Program under this + License may add an explicit geographical distribution limitation + excluding those countries, so that distribution is permitted only + in or among countries not thus excluded. In such case, this + License incorporates the limitation as if written in the body of + this License. + + 9. The Free Software Foundation may publish revised and/or new + versions of the General Public License from time to time. Such + new versions will be similar in spirit to the present version, but + may differ in detail to address new problems or concerns. + + Each version is given a distinguishing version number. If the + Program specifies a version number of this License which applies + to it and "any later version", you have the option of following + the terms and conditions either of that version or of any later + version published by the Free Software Foundation. If the Program + does not specify a version number of this License, you may choose + any version ever published by the Free Software Foundation. + + 10. If you wish to incorporate parts of the Program into other free + programs whose distribution conditions are different, write to the + author to ask for permission. For software which is copyrighted + by the Free Software Foundation, write to the Free Software + Foundation; we sometimes make exceptions for this. Our decision + will be guided by the two goals of preserving the free status of + all derivatives of our free software and of promoting the sharing + and reuse of software generally. + + NO WARRANTY + 11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO + WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE + LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT + HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT + WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT + NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND + FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE + QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE + PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY + SERVICING, REPAIR OR CORRECTION. + + 12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN + WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY + MODIFY AND/OR REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE + LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, + INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR + INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF + DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU + OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY + OTHER PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN + ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. + + END OF TERMS AND CONDITIONS +Appendix: How to Apply These Terms to Your New Programs +======================================================= + +If you develop a new program, and you want it to be of the greatest +possible use to the public, the best way to achieve this is to make it +free software which everyone can redistribute and change under these +terms. + + To do so, attach the following notices to the program. It is safest +to attach them to the start of each source file to most effectively +convey the exclusion of warranty; and each file should have at least +the "copyright" line and a pointer to where the full notice is found. + + ONE LINE TO GIVE THE PROGRAM'S NAME AND A BRIEF IDEA OF WHAT IT DOES. + Copyright (C) YEAR NAME OF AUTHOR + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA + + Also add information on how to contact you by electronic and paper +mail. + + If the program is interactive, make it output a short notice like +this when it starts in an interactive mode: + + Gnomovision version 69, Copyright (C) YEAR NAME OF AUTHOR + Gnomovision comes with ABSOLUTELY NO WARRANTY; for details + type `show w'. + This is free software, and you are welcome to redistribute it + under certain conditions; type `show c' for details. + + The hypothetical commands `show w' and `show c' should show the +appropriate parts of the General Public License. Of course, the +commands you use may be called something other than `show w' and `show +c'; they could even be mouse-clicks or menu items--whatever suits your +program. + + You should also get your employer (if you work as a programmer) or +your school, if any, to sign a "copyright disclaimer" for the program, +if necessary. Here is a sample; alter the names: + + Yoyodyne, Inc., hereby disclaims all copyright interest in the program + `Gnomovision' (which makes passes at compilers) written by James Hacker. + + SIGNATURE OF TY COON, 1 April 1989 + Ty Coon, President of Vice + + This General Public License does not permit incorporating your +program into proprietary programs. If your program is a subroutine +library, you may consider it more useful to permit linking proprietary +applications with the library. If this is what you want to do, use the +GNU Library General Public License instead of this License. + + +File: libgomp.info, Node: GNU Free Documentation License, Next: Funding, Prev: Copying, Up: Top + +GNU Free Documentation License +****************************** + + Version 1.3, 3 November 2008 + + Copyright (C) 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc. + `http://fsf.org/' + + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + 0. PREAMBLE + + The purpose of this License is to make a manual, textbook, or other + functional and useful document "free" in the sense of freedom: to + assure everyone the effective freedom to copy and redistribute it, + with or without modifying it, either commercially or + noncommercially. Secondarily, this License preserves for the + author and publisher a way to get credit for their work, while not + being considered responsible for modifications made by others. + + This License is a kind of "copyleft", which means that derivative + works of the document must themselves be free in the same sense. + It complements the GNU General Public License, which is a copyleft + license designed for free software. + + We have designed this License in order to use it for manuals for + free software, because free software needs free documentation: a + free program should come with manuals providing the same freedoms + that the software does. But this License is not limited to + software manuals; it can be used for any textual work, regardless + of subject matter or whether it is published as a printed book. + We recommend this License principally for works whose purpose is + instruction or reference. + + 1. APPLICABILITY AND DEFINITIONS + + This License applies to any manual or other work, in any medium, + that contains a notice placed by the copyright holder saying it + can be distributed under the terms of this License. Such a notice + grants a world-wide, royalty-free license, unlimited in duration, + to use that work under the conditions stated herein. The + "Document", below, refers to any such manual or work. Any member + of the public is a licensee, and is addressed as "you". You + accept the license if you copy, modify or distribute the work in a + way requiring permission under copyright law. + + A "Modified Version" of the Document means any work containing the + Document or a portion of it, either copied verbatim, or with + modifications and/or translated into another language. + + A "Secondary Section" is a named appendix or a front-matter section + of the Document that deals exclusively with the relationship of the + publishers or authors of the Document to the Document's overall + subject (or to related matters) and contains nothing that could + fall directly within that overall subject. (Thus, if the Document + is in part a textbook of mathematics, a Secondary Section may not + explain any mathematics.) The relationship could be a matter of + historical connection with the subject or with related matters, or + of legal, commercial, philosophical, ethical or political position + regarding them. + + The "Invariant Sections" are certain Secondary Sections whose + titles are designated, as being those of Invariant Sections, in + the notice that says that the Document is released under this + License. If a section does not fit the above definition of + Secondary then it is not allowed to be designated as Invariant. + The Document may contain zero Invariant Sections. If the Document + does not identify any Invariant Sections then there are none. + + The "Cover Texts" are certain short passages of text that are + listed, as Front-Cover Texts or Back-Cover Texts, in the notice + that says that the Document is released under this License. A + Front-Cover Text may be at most 5 words, and a Back-Cover Text may + be at most 25 words. + + A "Transparent" copy of the Document means a machine-readable copy, + represented in a format whose specification is available to the + general public, that is suitable for revising the document + straightforwardly with generic text editors or (for images + composed of pixels) generic paint programs or (for drawings) some + widely available drawing editor, and that is suitable for input to + text formatters or for automatic translation to a variety of + formats suitable for input to text formatters. A copy made in an + otherwise Transparent file format whose markup, or absence of + markup, has been arranged to thwart or discourage subsequent + modification by readers is not Transparent. An image format is + not Transparent if used for any substantial amount of text. A + copy that is not "Transparent" is called "Opaque". + + Examples of suitable formats for Transparent copies include plain + ASCII without markup, Texinfo input format, LaTeX input format, + SGML or XML using a publicly available DTD, and + standard-conforming simple HTML, PostScript or PDF designed for + human modification. Examples of transparent image formats include + PNG, XCF and JPG. Opaque formats include proprietary formats that + can be read and edited only by proprietary word processors, SGML or + XML for which the DTD and/or processing tools are not generally + available, and the machine-generated HTML, PostScript or PDF + produced by some word processors for output purposes only. + + The "Title Page" means, for a printed book, the title page itself, + plus such following pages as are needed to hold, legibly, the + material this License requires to appear in the title page. For + works in formats which do not have any title page as such, "Title + Page" means the text near the most prominent appearance of the + work's title, preceding the beginning of the body of the text. + + The "publisher" means any person or entity that distributes copies + of the Document to the public. + + A section "Entitled XYZ" means a named subunit of the Document + whose title either is precisely XYZ or contains XYZ in parentheses + following text that translates XYZ in another language. (Here XYZ + stands for a specific section name mentioned below, such as + "Acknowledgements", "Dedications", "Endorsements", or "History".) + To "Preserve the Title" of such a section when you modify the + Document means that it remains a section "Entitled XYZ" according + to this definition. + + The Document may include Warranty Disclaimers next to the notice + which states that this License applies to the Document. These + Warranty Disclaimers are considered to be included by reference in + this License, but only as regards disclaiming warranties: any other + implication that these Warranty Disclaimers may have is void and + has no effect on the meaning of this License. + + 2. VERBATIM COPYING + + You may copy and distribute the Document in any medium, either + commercially or noncommercially, provided that this License, the + copyright notices, and the license notice saying this License + applies to the Document are reproduced in all copies, and that you + add no other conditions whatsoever to those of this License. You + may not use technical measures to obstruct or control the reading + or further copying of the copies you make or distribute. However, + you may accept compensation in exchange for copies. If you + distribute a large enough number of copies you must also follow + the conditions in section 3. + + You may also lend copies, under the same conditions stated above, + and you may publicly display copies. + + 3. COPYING IN QUANTITY + + If you publish printed copies (or copies in media that commonly + have printed covers) of the Document, numbering more than 100, and + the Document's license notice requires Cover Texts, you must + enclose the copies in covers that carry, clearly and legibly, all + these Cover Texts: Front-Cover Texts on the front cover, and + Back-Cover Texts on the back cover. Both covers must also clearly + and legibly identify you as the publisher of these copies. The + front cover must present the full title with all words of the + title equally prominent and visible. You may add other material + on the covers in addition. Copying with changes limited to the + covers, as long as they preserve the title of the Document and + satisfy these conditions, can be treated as verbatim copying in + other respects. + + If the required texts for either cover are too voluminous to fit + legibly, you should put the first ones listed (as many as fit + reasonably) on the actual cover, and continue the rest onto + adjacent pages. + + If you publish or distribute Opaque copies of the Document + numbering more than 100, you must either include a + machine-readable Transparent copy along with each Opaque copy, or + state in or with each Opaque copy a computer-network location from + which the general network-using public has access to download + using public-standard network protocols a complete Transparent + copy of the Document, free of added material. If you use the + latter option, you must take reasonably prudent steps, when you + begin distribution of Opaque copies in quantity, to ensure that + this Transparent copy will remain thus accessible at the stated + location until at least one year after the last time you + distribute an Opaque copy (directly or through your agents or + retailers) of that edition to the public. + + It is requested, but not required, that you contact the authors of + the Document well before redistributing any large number of + copies, to give them a chance to provide you with an updated + version of the Document. + + 4. MODIFICATIONS + + You may copy and distribute a Modified Version of the Document + under the conditions of sections 2 and 3 above, provided that you + release the Modified Version under precisely this License, with + the Modified Version filling the role of the Document, thus + licensing distribution and modification of the Modified Version to + whoever possesses a copy of it. In addition, you must do these + things in the Modified Version: + + A. Use in the Title Page (and on the covers, if any) a title + distinct from that of the Document, and from those of + previous versions (which should, if there were any, be listed + in the History section of the Document). You may use the + same title as a previous version if the original publisher of + that version gives permission. + + B. List on the Title Page, as authors, one or more persons or + entities responsible for authorship of the modifications in + the Modified Version, together with at least five of the + principal authors of the Document (all of its principal + authors, if it has fewer than five), unless they release you + from this requirement. + + C. State on the Title page the name of the publisher of the + Modified Version, as the publisher. + + D. Preserve all the copyright notices of the Document. + + E. Add an appropriate copyright notice for your modifications + adjacent to the other copyright notices. + + F. Include, immediately after the copyright notices, a license + notice giving the public permission to use the Modified + Version under the terms of this License, in the form shown in + the Addendum below. + + G. Preserve in that license notice the full lists of Invariant + Sections and required Cover Texts given in the Document's + license notice. + + H. Include an unaltered copy of this License. + + I. Preserve the section Entitled "History", Preserve its Title, + and add to it an item stating at least the title, year, new + authors, and publisher of the Modified Version as given on + the Title Page. If there is no section Entitled "History" in + the Document, create one stating the title, year, authors, + and publisher of the Document as given on its Title Page, + then add an item describing the Modified Version as stated in + the previous sentence. + + J. Preserve the network location, if any, given in the Document + for public access to a Transparent copy of the Document, and + likewise the network locations given in the Document for + previous versions it was based on. These may be placed in + the "History" section. You may omit a network location for a + work that was published at least four years before the + Document itself, or if the original publisher of the version + it refers to gives permission. + + K. For any section Entitled "Acknowledgements" or "Dedications", + Preserve the Title of the section, and preserve in the + section all the substance and tone of each of the contributor + acknowledgements and/or dedications given therein. + + L. Preserve all the Invariant Sections of the Document, + unaltered in their text and in their titles. Section numbers + or the equivalent are not considered part of the section + titles. + + M. Delete any section Entitled "Endorsements". Such a section + may not be included in the Modified Version. + + N. Do not retitle any existing section to be Entitled + "Endorsements" or to conflict in title with any Invariant + Section. + + O. Preserve any Warranty Disclaimers. + + If the Modified Version includes new front-matter sections or + appendices that qualify as Secondary Sections and contain no + material copied from the Document, you may at your option + designate some or all of these sections as invariant. To do this, + add their titles to the list of Invariant Sections in the Modified + Version's license notice. These titles must be distinct from any + other section titles. + + You may add a section Entitled "Endorsements", provided it contains + nothing but endorsements of your Modified Version by various + parties--for example, statements of peer review or that the text + has been approved by an organization as the authoritative + definition of a standard. + + You may add a passage of up to five words as a Front-Cover Text, + and a passage of up to 25 words as a Back-Cover Text, to the end + of the list of Cover Texts in the Modified Version. Only one + passage of Front-Cover Text and one of Back-Cover Text may be + added by (or through arrangements made by) any one entity. If the + Document already includes a cover text for the same cover, + previously added by you or by arrangement made by the same entity + you are acting on behalf of, you may not add another; but you may + replace the old one, on explicit permission from the previous + publisher that added the old one. + + The author(s) and publisher(s) of the Document do not by this + License give permission to use their names for publicity for or to + assert or imply endorsement of any Modified Version. + + 5. COMBINING DOCUMENTS + + You may combine the Document with other documents released under + this License, under the terms defined in section 4 above for + modified versions, provided that you include in the combination + all of the Invariant Sections of all of the original documents, + unmodified, and list them all as Invariant Sections of your + combined work in its license notice, and that you preserve all + their Warranty Disclaimers. + + The combined work need only contain one copy of this License, and + multiple identical Invariant Sections may be replaced with a single + copy. If there are multiple Invariant Sections with the same name + but different contents, make the title of each such section unique + by adding at the end of it, in parentheses, the name of the + original author or publisher of that section if known, or else a + unique number. Make the same adjustment to the section titles in + the list of Invariant Sections in the license notice of the + combined work. + + In the combination, you must combine any sections Entitled + "History" in the various original documents, forming one section + Entitled "History"; likewise combine any sections Entitled + "Acknowledgements", and any sections Entitled "Dedications". You + must delete all sections Entitled "Endorsements." + + 6. COLLECTIONS OF DOCUMENTS + + You may make a collection consisting of the Document and other + documents released under this License, and replace the individual + copies of this License in the various documents with a single copy + that is included in the collection, provided that you follow the + rules of this License for verbatim copying of each of the + documents in all other respects. + + You may extract a single document from such a collection, and + distribute it individually under this License, provided you insert + a copy of this License into the extracted document, and follow + this License in all other respects regarding verbatim copying of + that document. + + 7. AGGREGATION WITH INDEPENDENT WORKS + + A compilation of the Document or its derivatives with other + separate and independent documents or works, in or on a volume of + a storage or distribution medium, is called an "aggregate" if the + copyright resulting from the compilation is not used to limit the + legal rights of the compilation's users beyond what the individual + works permit. When the Document is included in an aggregate, this + License does not apply to the other works in the aggregate which + are not themselves derivative works of the Document. + + If the Cover Text requirement of section 3 is applicable to these + copies of the Document, then if the Document is less than one half + of the entire aggregate, the Document's Cover Texts may be placed + on covers that bracket the Document within the aggregate, or the + electronic equivalent of covers if the Document is in electronic + form. Otherwise they must appear on printed covers that bracket + the whole aggregate. + + 8. TRANSLATION + + Translation is considered a kind of modification, so you may + distribute translations of the Document under the terms of section + 4. Replacing Invariant Sections with translations requires special + permission from their copyright holders, but you may include + translations of some or all Invariant Sections in addition to the + original versions of these Invariant Sections. You may include a + translation of this License, and all the license notices in the + Document, and any Warranty Disclaimers, provided that you also + include the original English version of this License and the + original versions of those notices and disclaimers. In case of a + disagreement between the translation and the original version of + this License or a notice or disclaimer, the original version will + prevail. + + If a section in the Document is Entitled "Acknowledgements", + "Dedications", or "History", the requirement (section 4) to + Preserve its Title (section 1) will typically require changing the + actual title. + + 9. TERMINATION + + You may not copy, modify, sublicense, or distribute the Document + except as expressly provided under this License. Any attempt + otherwise to copy, modify, sublicense, or distribute it is void, + and will automatically terminate your rights under this License. + + However, if you cease all violation of this License, then your + license from a particular copyright holder is reinstated (a) + provisionally, unless and until the copyright holder explicitly + and finally terminates your license, and (b) permanently, if the + copyright holder fails to notify you of the violation by some + reasonable means prior to 60 days after the cessation. + + Moreover, your license from a particular copyright holder is + reinstated permanently if the copyright holder notifies you of the + violation by some reasonable means, this is the first time you have + received notice of violation of this License (for any work) from + that copyright holder, and you cure the violation prior to 30 days + after your receipt of the notice. + + Termination of your rights under this section does not terminate + the licenses of parties who have received copies or rights from + you under this License. If your rights have been terminated and + not permanently reinstated, receipt of a copy of some or all of + the same material does not give you any rights to use it. + + 10. FUTURE REVISIONS OF THIS LICENSE + + The Free Software Foundation may publish new, revised versions of + the GNU Free Documentation License from time to time. Such new + versions will be similar in spirit to the present version, but may + differ in detail to address new problems or concerns. See + `http://www.gnu.org/copyleft/'. + + Each version of the License is given a distinguishing version + number. If the Document specifies that a particular numbered + version of this License "or any later version" applies to it, you + have the option of following the terms and conditions either of + that specified version or of any later version that has been + published (not as a draft) by the Free Software Foundation. If + the Document does not specify a version number of this License, + you may choose any version ever published (not as a draft) by the + Free Software Foundation. If the Document specifies that a proxy + can decide which future versions of this License can be used, that + proxy's public statement of acceptance of a version permanently + authorizes you to choose that version for the Document. + + 11. RELICENSING + + "Massive Multiauthor Collaboration Site" (or "MMC Site") means any + World Wide Web server that publishes copyrightable works and also + provides prominent facilities for anybody to edit those works. A + public wiki that anybody can edit is an example of such a server. + A "Massive Multiauthor Collaboration" (or "MMC") contained in the + site means any set of copyrightable works thus published on the MMC + site. + + "CC-BY-SA" means the Creative Commons Attribution-Share Alike 3.0 + license published by Creative Commons Corporation, a not-for-profit + corporation with a principal place of business in San Francisco, + California, as well as future copyleft versions of that license + published by that same organization. + + "Incorporate" means to publish or republish a Document, in whole or + in part, as part of another Document. + + An MMC is "eligible for relicensing" if it is licensed under this + License, and if all works that were first published under this + License somewhere other than this MMC, and subsequently + incorporated in whole or in part into the MMC, (1) had no cover + texts or invariant sections, and (2) were thus incorporated prior + to November 1, 2008. + + The operator of an MMC Site may republish an MMC contained in the + site under CC-BY-SA on the same site at any time before August 1, + 2009, provided the MMC is eligible for relicensing. + + +ADDENDUM: How to use this License for your documents +==================================================== + +To use this License in a document you have written, include a copy of +the License in the document and put the following copyright and license +notices just after the title page: + + Copyright (C) YEAR YOUR NAME. + Permission is granted to copy, distribute and/or modify this document + under the terms of the GNU Free Documentation License, Version 1.3 + or any later version published by the Free Software Foundation; + with no Invariant Sections, no Front-Cover Texts, and no Back-Cover + Texts. A copy of the license is included in the section entitled ``GNU + Free Documentation License''. + + If you have Invariant Sections, Front-Cover Texts and Back-Cover +Texts, replace the "with...Texts." line with this: + + with the Invariant Sections being LIST THEIR TITLES, with + the Front-Cover Texts being LIST, and with the Back-Cover Texts + being LIST. + + If you have Invariant Sections without Cover Texts, or some other +combination of the three, merge those two alternatives to suit the +situation. + + If your document contains nontrivial examples of program code, we +recommend releasing these examples in parallel under your choice of +free software license, such as the GNU General Public License, to +permit their use in free software. + + +File: libgomp.info, Node: Funding, Next: Index, Prev: GNU Free Documentation License, Up: Top + +Funding Free Software +********************* + +If you want to have more free software a few years from now, it makes +sense for you to help encourage people to contribute funds for its +development. The most effective approach known is to encourage +commercial redistributors to donate. + + Users of free software systems can boost the pace of development by +encouraging for-a-fee distributors to donate part of their selling price +to free software developers--the Free Software Foundation, and others. + + The way to convince distributors to do this is to demand it and +expect it from them. So when you compare distributors, judge them +partly by how much they give to free software development. Show +distributors they must compete to be the one who gives the most. + + To make this approach work, you must insist on numbers that you can +compare, such as, "We will donate ten dollars to the Frobnitz project +for each disk sold." Don't be satisfied with a vague promise, such as +"A portion of the profits are donated," since it doesn't give a basis +for comparison. + + Even a precise fraction "of the profits from this disk" is not very +meaningful, since creative accounting and unrelated business decisions +can greatly alter what fraction of the sales price counts as profit. +If the price you pay is $50, ten percent of the profit is probably less +than a dollar; it might be a few cents, or nothing at all. + + Some redistributors do development work themselves. This is useful +too; but to keep everyone honest, you need to inquire how much they do, +and what kind. Some kinds of development make much more long-term +difference than others. For example, maintaining a separate version of +a program contributes very little; maintaining the standard version of a +program for the whole community contributes much. Easy new ports +contribute little, since someone else would surely do them; difficult +ports such as adding a new CPU to the GNU Compiler Collection +contribute more; major new features or packages contribute the most. + + By establishing the idea that supporting further development is "the +proper thing to do" when distributing free software for a fee, we can +assure a steady flow of resources into making more free software. + + Copyright (C) 1994 Free Software Foundation, Inc. + Verbatim copying and redistribution of this section is permitted + without royalty; alteration is not permitted. + + +File: libgomp.info, Node: Index, Prev: Funding, Up: Top + +Index +***** + + +* Menu: + +* Environment Variable <1>: GOMP_STACKSIZE. (line 6) +* Environment Variable <2>: GOMP_CPU_AFFINITY. (line 6) +* Environment Variable <3>: OMP_WAIT_POLICY. (line 6) +* Environment Variable <4>: OMP_THREAD_LIMIT. (line 6) +* Environment Variable <5>: OMP_STACKSIZE. (line 6) +* Environment Variable <6>: OMP_SCHEDULE. (line 6) +* Environment Variable <7>: OMP_NUM_THREADS. (line 6) +* Environment Variable <8>: OMP_NESTED. (line 6) +* Environment Variable <9>: OMP_MAX_ACTIVE_LEVELS. (line 6) +* Environment Variable: OMP_DYNAMIC. (line 6) +* FDL, GNU Free Documentation License: GNU Free Documentation License. + (line 6) +* Implementation specific setting <1>: GOMP_STACKSIZE. (line 6) +* Implementation specific setting <2>: OMP_SCHEDULE. (line 6) +* Implementation specific setting <3>: OMP_NUM_THREADS. (line 6) +* Implementation specific setting: OMP_NESTED. (line 6) +* Introduction: Top. (line 6) + + + +Tag Table: +Node: Top2072 +Node: Enabling OpenMP3266 +Node: Runtime Library Routines4051 +Node: omp_get_active_level6426 +Node: omp_get_ancestor_thread_num7130 +Node: omp_get_dynamic8057 +Node: omp_get_level8935 +Node: omp_get_max_active_levels9559 +Node: omp_get_max_threads10262 +Node: omp_get_nested11018 +Node: omp_get_num_procs11930 +Node: omp_get_num_threads12448 +Node: omp_get_schedule13530 +Node: omp_get_team_size14446 +Node: omp_get_thread_limit15408 +Node: omp_get_thread_num16031 +Node: omp_in_parallel16899 +Node: omp_set_dynamic17549 +Node: omp_set_max_active_levels18389 +Node: omp_set_nested19169 +Node: omp_set_num_threads20048 +Node: omp_set_schedule20884 +Node: omp_init_lock21955 +Node: omp_set_lock22606 +Node: omp_test_lock23457 +Node: omp_unset_lock24486 +Node: omp_destroy_lock25413 +Node: omp_init_nest_lock26087 +Node: omp_set_nest_lock26820 +Node: omp_test_nest_lock27731 +Node: omp_unset_nest_lock28829 +Node: omp_destroy_nest_lock29840 +Node: omp_get_wtick30588 +Node: omp_get_wtime31179 +Node: Environment Variables31953 +Node: OMP_DYNAMIC33014 +Node: OMP_MAX_ACTIVE_LEVELS33582 +Node: OMP_NESTED34219 +Node: OMP_NUM_THREADS34823 +Node: OMP_SCHEDULE35391 +Node: OMP_STACKSIZE36085 +Node: OMP_THREAD_LIMIT36909 +Node: OMP_WAIT_POLICY37504 +Node: GOMP_CPU_AFFINITY38069 +Node: GOMP_STACKSIZE39570 +Node: The libgomp ABI40378 +Node: Implementing MASTER construct41177 +Node: Implementing CRITICAL construct41591 +Node: Implementing ATOMIC construct42330 +Node: Implementing FLUSH construct42811 +Node: Implementing BARRIER construct43082 +Node: Implementing THREADPRIVATE construct43351 +Node: Implementing PRIVATE clause44003 +Node: Implementing FIRSTPRIVATE LASTPRIVATE COPYIN and COPYPRIVATE clauses44584 +Node: Implementing REDUCTION clause45908 +Node: Implementing PARALLEL construct46465 +Node: Implementing FOR construct47722 +Node: Implementing ORDERED construct49720 +Node: Implementing SECTIONS construct50026 +Node: Implementing SINGLE construct50792 +Node: Reporting Bugs51454 +Node: Copying51764 +Node: GNU Free Documentation License70974 +Node: Funding96116 +Node: Index98633 + +End Tag Table |