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Diffstat (limited to 'gcc-4.3.1/gcc/ada/s-stache.ads')
| -rw-r--r-- | gcc-4.3.1/gcc/ada/s-stache.ads | 86 |
1 files changed, 86 insertions, 0 deletions
diff --git a/gcc-4.3.1/gcc/ada/s-stache.ads b/gcc-4.3.1/gcc/ada/s-stache.ads new file mode 100644 index 000000000..5e2c30f77 --- /dev/null +++ b/gcc-4.3.1/gcc/ada/s-stache.ads @@ -0,0 +1,86 @@ +------------------------------------------------------------------------------ +-- -- +-- 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 -- +-- -- +-- S p e c -- +-- -- +-- Copyright (C) 1999-2007, 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, 51 Franklin Street, Fifth Floor, -- +-- Boston, MA 02110-1301, 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 package provides a system-independent implementation of stack +-- checking using comparison with stack base and limit. + +-- This package defines basic types and objects. Operations related to +-- stack checking can be found in package System.Stack_Checking.Operations. + +pragma Warnings (Off); +pragma Compiler_Unit; +pragma Warnings (On); + +with System.Storage_Elements; + +package System.Stack_Checking is + pragma Preelaborate; + pragma Elaborate_Body; + -- This unit has a junk null body. The reason is that historically we + -- used to have a real body, and it causes bootstrapping path problems + -- to eliminate it, since the old body may still be present in the + -- compilation environment for a build. + + type Stack_Info is record + Limit : System.Address := System.Null_Address; + Base : System.Address := System.Null_Address; + Size : System.Storage_Elements.Storage_Offset := 0; + end record; + -- This record may be part of a larger data structure like the + -- task control block in the tasking case. + -- This specific layout has the advantage of being compatible with the + -- Intel x86 BOUNDS instruction. + + type Stack_Access is access all Stack_Info; + -- Unique local storage associated with a specific task. This storage is + -- used for the stack base and limit, and is returned by Checked_Self. + -- Only self may write this information, it may be read by any task. + -- At no time the address range Limit .. Base (or Base .. Limit for + -- upgrowing stack) may contain any address that is part of another stack. + -- The Stack_Access may be part of a larger data structure. + + Multi_Processor : constant Boolean := False; -- Not supported yet + +private + + Null_Stack_Info : aliased Stack_Info := + (Limit => System.Null_Address, + Base => System.Null_Address, + Size => 0); + -- Use explicit assignment to avoid elaboration code (call to init proc) + + Null_Stack : constant Stack_Access := Null_Stack_Info'Access; + -- Stack_Access value that will return a Stack_Base and Stack_Limit + -- that fail any stack check. + +end System.Stack_Checking; |