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Diffstat (limited to 'gcc/ada/5stpopse.adb')
| -rw-r--r-- | gcc/ada/5stpopse.adb | 204 |
1 files changed, 0 insertions, 204 deletions
diff --git a/gcc/ada/5stpopse.adb b/gcc/ada/5stpopse.adb deleted file mode 100644 index a6c1e9e89b3..00000000000 --- a/gcc/ada/5stpopse.adb +++ /dev/null @@ -1,204 +0,0 @@ ------------------------------------------------------------------------------- --- -- --- GNU ADA RUN-TIME LIBRARY (GNARL) COMPONENTS -- --- -- --- SYSTEM.TASK_PRIMITIVES.OPERATIONS.SELF -- --- -- --- B o d y -- --- -- --- Copyright (C) 1992-2002, Free Software Foundation, Inc. -- --- -- --- GNARL is free software; you can redistribute it and/or modify it under -- --- terms of the GNU General Public License as published by the Free Soft- -- --- ware Foundation; either version 2, or (at your option) any later ver- -- --- sion. GNARL is distributed in the hope that it will be useful, but WITH- -- --- OUT 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 distributed with GNARL; see file COPYING. If not, write -- --- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, -- --- MA 02111-1307, USA. -- --- -- --- As a special exception, if other files instantiate generics from this -- --- unit, or you link this unit with other files to produce an executable, -- --- this unit does not by itself cause the resulting executable to be -- --- covered by the GNU General Public License. This exception does not -- --- however invalidate any other reasons why the executable file might be -- --- covered by the GNU Public License. -- --- -- --- GNARL was developed by the GNARL team at Florida State University. -- --- Extensive contributions were provided by Ada Core Technologies, Inc. -- --- -- ------------------------------------------------------------------------------- - --- This is a Solaris Sparc (native) version of this package. - -with System.Machine_Code; --- used for Asm - -separate (System.Task_Primitives.Operations) - ----------- --- Self -- ----------- - --- For Solaris version of RTS, we use a short cut to get the self --- information faster: - --- We have noticed that on Sparc Solaris, the register g7 always --- contains the address near the frame pointer (fp) of the active --- thread (fixed offset). This means, if we declare a variable near --- the top of the stack for each threads (in our case in the task wrapper) --- and let the variable hold the Task_ID information, we can get the --- value without going through the thr_getspecific kernel call. --- --- There are two things to take care in this trick. --- --- 1) We need to calculate the offset between the g7 value and the --- local variable address. --- Possible Solutions : --- a) Use gdb to figure out the offset. --- b) Figure it out during the elaboration of RTS by, say, --- creating a dummy task. --- We used solution a) mainly because it is more efficient and keeps --- the RTS from being cluttered with stuff that we won't be used --- for all environments (i.e., we would have to at least introduce --- new interfaces). --- --- On Sparc Solaris the offset was #10#108# (= #16#6b#) with gcc 2.7.2. --- With gcc 2.8.0, the offset is #10#116# (= #16#74#). --- --- 2) We can not use the same offset business for the main thread --- because we do not use a wrapper for the main thread. --- Previousely, we used the difference between g7 and fp to determine --- wether a task was the main task or not. But this was obviousely --- wrong since it worked only for tasks that use small amount of --- stack. --- So, we now take advantage of the code that recognizes foreign --- threads (see below) for the main task. --- --- NOTE: What we are doing here is ABSOLUTELY for Solaris 2.4, 2.5 and 2.6 --- on Sun. - --- We need to make sure this is OK when we move to other versions --- of the same OS. - --- We always can go back to the old way of doing this and we include --- the code which use thr_getspecifics. Also, look for %%%%% --- in comments for other necessary modifications. - --- This code happens to work with Solaris 2.5.1 too, but with gcc --- 2.8.0, this offset is different. - --- ??? Try to rethink the approach here to get a more flexible --- solution at run time ? - --- One other solution (close to 1-b) would be to add some scanning --- routine in Enter_Task to compute the offset since now we have --- a magic number at the beginning of the task code. - --- function Self return Task_ID is --- Temp : aliased System.Address; --- Result : Interfaces.C.int; --- --- begin --- Result := thr_getspecific (ATCB_Key, Temp'Unchecked_Access); --- pragma Assert (Result = 0); --- return To_Task_ID (Temp); --- end Self; - --- To make Ada tasks and C threads interoperate better, we have --- added some functionality to Self. Suppose a C main program --- (with threads) calls an Ada procedure and the Ada procedure --- calls the tasking run-time system. Eventually, a call will be --- made to self. Since the call is not coming from an Ada task, --- there will be no corresponding ATCB. - --- (The entire Ada run-time system may not have been elaborated, --- either, but that is a different problem, that we will need to --- solve another way.) - --- What we do in Self is to catch references that do not come --- from recognized Ada tasks, and create an ATCB for the calling --- thread. - --- The new ATCB will be "detached" from the normal Ada task --- master hierarchy, much like the existing implicitly created --- signal-server tasks. - --- We will also use such points to poll for disappearance of the --- threads associated with any implicit ATCBs that we created --- earlier, and take the opportunity to recover them. - --- A nasty problem here is the limitations of the compilation --- order dependency, and in particular the GNARL/GNULLI layering. --- To initialize an ATCB we need to assume System.Tasking has --- been elaborated. - -function Self return Task_ID is - ATCB_Magic_Code : constant := 16#ADAADAAD#; - -- This is used to allow us to catch attempts to call Self - -- from outside an Ada task, with high probability. - -- For an Ada task, Task_Wrapper.Magic_Number = ATCB_Magic_Code. - - type Iptr is access Interfaces.C.unsigned; - function To_Iptr is new Unchecked_Conversion (Interfaces.C.unsigned, Iptr); - - type Ptr is access Task_ID; - function To_Ptr is new Unchecked_Conversion (Interfaces.C.unsigned, Ptr); - - X : Ptr; - Result : Interfaces.C.int; - - function Get_G7 return Interfaces.C.unsigned; - pragma Inline (Get_G7); - - use System.Machine_Code; - - ------------ - -- Get_G7 -- - ------------ - - function Get_G7 return Interfaces.C.unsigned is - Result : Interfaces.C.unsigned; - - begin - Asm ("mov %%g7,%0", Interfaces.C.unsigned'Asm_Output ("=r", Result)); - return Result; - end Get_G7; - --- Start of processing for Self - -begin - if To_Iptr (Get_G7 - 120).all /= - Interfaces.C.unsigned (ATCB_Magic_Code) - then - -- Check whether this is a thread we have seen before (e.g the - -- main task). - -- 120 = 116 + Magic_Type'Size/System.Storage_Unit - - declare - Unknown_Task : aliased System.Address; - - begin - Result := - thr_getspecific (ATCB_Key, Unknown_Task'Unchecked_Access); - - pragma Assert (Result = 0); - - if Unknown_Task = System.Null_Address then - - -- We are seeing this thread for the first time. - - return New_Fake_ATCB (Get_G7); - - else - return To_Task_ID (Unknown_Task); - end if; - end; - end if; - - X := To_Ptr (Get_G7 - 116); - return X.all; - -end Self; |