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-- Copyright (c) 2016, Natacha Porté --
-- --
-- Permission to use, copy, modify, and distribute this software for any --
-- purpose with or without fee is hereby granted, provided that the above --
-- copyright notice and this permission notice appear in all copies. --
-- --
-- THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES --
-- WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF --
-- MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR --
-- ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES --
-- WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN --
-- ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF --
-- OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. --
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-- Natools.Parallelism provides generic procedures to help with simple --
-- parallelisation needs. --
------------------------------------------------------------------------------
package Natools.Parallelism is
pragma Pure;
generic
type Global_State (<>) is limited private;
-- State common to all jobs, only accessed from protected subprograms
type Job_State is limited private;
-- State of a single job, each worker task having its own
with procedure Initialize_Job
(Global : in out Global_State;
Job : out Job_State) is <>;
-- Initialize Job and update Global as needed
with procedure Do_Job (Job : in out Job_State) is <>;
-- Perform the job in parallel
with procedure Gather_Result
(Global : in out Global_State;
Job : in Job_State) is <>;
-- Update Global with results stored in Job
with function Is_Finished (Global : in Global_State)
return Boolean is <>;
-- Check whether there is still a job to do
procedure Single_Accumulator_Run
(Global : in out Global_State;
Task_Count : in Positive);
generic
type Global_State (<>) is limited private;
-- State common to all jobs, only accessed from protected subprograms
type Task_Result is limited private;
-- Accumulated result in a single task
type Job_Description is limited private;
-- Parameters for a given job
with procedure Initialize (Result : in out Task_Result) is <>;
-- Initialize Result for the current task
with procedure Get_Next_Job
(Global : in out Global_State;
Job : out Job_Description;
Terminated : out Boolean) is <>;
-- If there is a next job available from Global, set Terminated
-- to False and initialize Job, otherwise set Terminated to True.
with procedure Do_Job
(Result : in out Task_Result;
Job : in Job_Description) is <>;
-- Perform the job in parallel
with procedure Gather_Result
(Global : in out Global_State;
Partial : in Task_Result) is <>;
-- Update Global with results stored in Partial
procedure Per_Task_Accumulator_Run
(Global : in out Global_State;
Task_Count : in Positive);
end Natools.Parallelism;