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Diffstat (limited to 'gcc/ada/s-stchop.adb')
| -rw-r--r-- | gcc/ada/s-stchop.adb | 279 |
1 files changed, 0 insertions, 279 deletions
diff --git a/gcc/ada/s-stchop.adb b/gcc/ada/s-stchop.adb deleted file mode 100644 index 05b13dc..0000000 --- a/gcc/ada/s-stchop.adb +++ /dev/null @@ -1,279 +0,0 @@ ------------------------------------------------------------------------------- --- -- --- GNAT RUN-TIME LIBRARY (GNARL) COMPONENTS -- --- -- --- S Y S T E M . S T A C K _ C H E C K I N G . O P E R A T I O N S -- --- -- --- B o d y -- --- -- --- Copyright (C) 1999-2014, 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 3, or (at your option) any later ver- -- --- sion. GNAT 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. -- --- -- --- As a special exception under Section 7 of GPL version 3, you are granted -- --- additional permissions described in the GCC Runtime Library Exception, -- --- version 3.1, as published by the Free Software Foundation. -- --- -- --- You should have received a copy of the GNU General Public License and -- --- a copy of the GCC Runtime Library Exception along with this program; -- --- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -- --- <http://www.gnu.org/licenses/>. -- --- -- --- GNARL was developed by the GNARL team at Florida State University. -- --- Extensive contributions were provided by Ada Core Technologies, Inc. -- --- -- ------------------------------------------------------------------------------- - --- This is the general implementation of this package. There is a VxWorks --- specific version of this package (s-stchop-vxworks.adb). This file should --- be kept synchronized with it. - -pragma Restrictions (No_Elaboration_Code); --- We want to guarantee the absence of elaboration code because the --- binder does not handle references to this package. - -with System.Storage_Elements; use System.Storage_Elements; -with System.Parameters; use System.Parameters; -with System.Soft_Links; -with System.CRTL; - -package body System.Stack_Checking.Operations is - - Kilobyte : constant := 1024; - - function Set_Stack_Info - (Stack : not null access Stack_Access) return Stack_Access; - -- The function Set_Stack_Info is the actual function that updates the - -- cache containing a pointer to the Stack_Info. It may also be used for - -- detecting asynchronous abort in combination with Invalidate_Self_Cache. - -- - -- Set_Stack_Info should do the following things in order: - -- 1) Get the Stack_Access value for the current task - -- 2) Set Stack.all to the value obtained in 1) - -- 3) Optionally Poll to check for asynchronous abort - -- - -- This order is important because if at any time a write to the stack - -- cache is pending, that write should be followed by a Poll to prevent - -- losing signals. - -- - -- Note: This function must be compiled with Polling turned off - -- - -- Note: on systems with real thread-local storage, Set_Stack_Info should - -- return an access value for such local storage. In those cases the cache - -- will always be up-to-date. - - ---------------------------- - -- Invalidate_Stack_Cache -- - ---------------------------- - - procedure Invalidate_Stack_Cache (Any_Stack : Stack_Access) is - pragma Warnings (Off, Any_Stack); - begin - Cache := Null_Stack; - end Invalidate_Stack_Cache; - - ----------------------------- - -- Notify_Stack_Attributes -- - ----------------------------- - - procedure Notify_Stack_Attributes - (Initial_SP : System.Address; - Size : System.Storage_Elements.Storage_Offset) - is - My_Stack : constant Stack_Access := Soft_Links.Get_Stack_Info.all; - - -- We piggyback on the 'Limit' field to store what will be used as the - -- 'Base' and leave the 'Size' alone to not interfere with the logic in - -- Set_Stack_Info below. - - pragma Unreferenced (Size); - - begin - My_Stack.Limit := Initial_SP; - end Notify_Stack_Attributes; - - -------------------- - -- Set_Stack_Info -- - -------------------- - - function Set_Stack_Info - (Stack : not null access Stack_Access) return Stack_Access - is - type Frame_Mark is null record; - Frame_Location : Frame_Mark; - Frame_Address : constant Address := Frame_Location'Address; - - My_Stack : Stack_Access; - Limit_Chars : System.Address; - Limit : Integer; - - begin - -- The order of steps 1 .. 3 is important, see specification - - -- 1) Get the Stack_Access value for the current task - - My_Stack := Soft_Links.Get_Stack_Info.all; - - if My_Stack.Base = Null_Address then - - -- First invocation, initialize based on the assumption that there - -- are Environment_Stack_Size bytes available beyond the current - -- frame address. - - if My_Stack.Size = 0 then - My_Stack.Size := Storage_Offset (Default_Env_Stack_Size); - - -- When the environment variable GNAT_STACK_LIMIT is set, set - -- Environment_Stack_Size to that number of kB. - - Limit_Chars := System.CRTL.getenv ("GNAT_STACK_LIMIT" & ASCII.NUL); - - if Limit_Chars /= Null_Address then - Limit := System.CRTL.atoi (Limit_Chars); - - if Limit >= 0 then - My_Stack.Size := Storage_Offset (Limit) * Kilobyte; - end if; - end if; - end if; - - -- If a stack base address has been registered, honor it. Fallback to - -- the address of a local object otherwise. - - My_Stack.Base := - (if My_Stack.Limit /= System.Null_Address - then My_Stack.Limit else Frame_Address); - - if Stack_Grows_Down then - - -- Prevent wrap-around on too big stack sizes - - My_Stack.Limit := My_Stack.Base - My_Stack.Size; - - if My_Stack.Limit > My_Stack.Base then - My_Stack.Limit := Address'First; - end if; - - else - My_Stack.Limit := My_Stack.Base + My_Stack.Size; - - -- Prevent wrap-around on too big stack sizes - - if My_Stack.Limit < My_Stack.Base then - My_Stack.Limit := Address'Last; - end if; - end if; - end if; - - -- 2) Set Stack.all to the value obtained in 1) - - Stack.all := My_Stack; - - -- 3) Optionally Poll to check for asynchronous abort - - if Soft_Links.Check_Abort_Status.all /= 0 then - raise Standard'Abort_Signal; - end if; - - -- Never trust the cached value, but return local copy - - return My_Stack; - end Set_Stack_Info; - - ----------------- - -- Stack_Check -- - ----------------- - - function Stack_Check - (Stack_Address : System.Address) return Stack_Access - is - type Frame_Marker is null record; - Marker : Frame_Marker; - Cached_Stack : constant Stack_Access := Cache; - Frame_Address : constant System.Address := Marker'Address; - - begin - -- The parameter may have wrapped around in System.Address arithmetics. - -- In that case, we have no other choices than raising the exception. - - if (Stack_Grows_Down and then - Stack_Address > Frame_Address) - or else - (not Stack_Grows_Down and then - Stack_Address < Frame_Address) - then - raise Storage_Error with "stack overflow detected"; - end if; - - -- This function first does a "cheap" check which is correct if it - -- succeeds. In case of failure, the full check is done. Ideally the - -- cheap check should be done in an optimized manner, or be inlined. - - if (Stack_Grows_Down and then - (Frame_Address <= Cached_Stack.Base - and then - Stack_Address > Cached_Stack.Limit)) - or else - (not Stack_Grows_Down and then - (Frame_Address >= Cached_Stack.Base - and then - Stack_Address < Cached_Stack.Limit)) - then - -- Cached_Stack is valid as it passed the stack check - - return Cached_Stack; - end if; - - Full_Check : - declare - My_Stack : constant Stack_Access := Set_Stack_Info (Cache'Access); - -- At this point Stack.all might already be invalid, so - -- it is essential to use our local copy of Stack. - - begin - if (Stack_Grows_Down and then - (not (Frame_Address <= My_Stack.Base))) - or else - (not Stack_Grows_Down and then - (not (Frame_Address >= My_Stack.Base))) - then - -- The returned Base is lower than the stored one, so assume that - -- the original one wasn't right and use the current Frame_Address - -- as new one. This allows Base to be initialized with the - -- Frame_Address as approximation. During initialization the - -- Frame_Address will be close to the stack base anyway: the - -- difference should be compensated for in the stack reserve. - - My_Stack.Base := Frame_Address; - end if; - - if (Stack_Grows_Down - and then Stack_Address < My_Stack.Limit) - or else - (not Stack_Grows_Down - and then Stack_Address > My_Stack.Limit) - then - raise Storage_Error with "stack overflow detected"; - end if; - - return My_Stack; - end Full_Check; - end Stack_Check; - - ------------------------ - -- Update_Stack_Cache -- - ------------------------ - - procedure Update_Stack_Cache (Stack : Stack_Access) is - begin - if not Multi_Processor then - Cache := Stack; - end if; - end Update_Stack_Cache; - -end System.Stack_Checking.Operations; |