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Diffstat (limited to 'gcc-4.4.3/gcc/ada/s-secsta.adb')
-rw-r--r-- | gcc-4.4.3/gcc/ada/s-secsta.adb | 541 |
1 files changed, 0 insertions, 541 deletions
diff --git a/gcc-4.4.3/gcc/ada/s-secsta.adb b/gcc-4.4.3/gcc/ada/s-secsta.adb deleted file mode 100644 index 9f265fddb..000000000 --- a/gcc-4.4.3/gcc/ada/s-secsta.adb +++ /dev/null @@ -1,541 +0,0 @@ ------------------------------------------------------------------------------- --- -- --- GNAT COMPILER COMPONENTS -- --- -- --- S Y S T E M . S E C O N D A R Y _ S T A C K -- --- -- --- B o d y -- --- -- --- Copyright (C) 1992-2009, Free Software Foundation, Inc. -- --- -- --- GNAT 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/>. -- --- -- --- GNAT was originally developed by the GNAT team at New York University. -- --- Extensive contributions were provided by Ada Core Technologies Inc. -- --- -- ------------------------------------------------------------------------------- - -pragma Warnings (Off); -pragma Compiler_Unit; -pragma Warnings (On); - -with System.Soft_Links; -with System.Parameters; -with Ada.Unchecked_Conversion; -with Ada.Unchecked_Deallocation; - -package body System.Secondary_Stack is - - package SSL renames System.Soft_Links; - - use type SSE.Storage_Offset; - use type System.Parameters.Size_Type; - - SS_Ratio_Dynamic : constant Boolean := - Parameters.Sec_Stack_Ratio = Parameters.Dynamic; - -- There are two entirely different implementations of the secondary - -- stack mechanism in this unit, and this Boolean is used to select - -- between them (at compile time, so the generated code will contain - -- only the code for the desired variant). If SS_Ratio_Dynamic is - -- True, then the secondary stack is dynamically allocated from the - -- heap in a linked list of chunks. If SS_Ration_Dynamic is False, - -- then the secondary stack is allocated statically by grabbing a - -- section of the primary stack and using it for this purpose. - - type Memory is array (SS_Ptr range <>) of SSE.Storage_Element; - for Memory'Alignment use Standard'Maximum_Alignment; - -- This is the type used for actual allocation of secondary stack - -- areas. We require maximum alignment for all such allocations. - - --------------------------------------------------------------- - -- Data Structures for Dynamically Allocated Secondary Stack -- - --------------------------------------------------------------- - - -- The following is a diagram of the data structures used for the - -- case of a dynamically allocated secondary stack, where the stack - -- is allocated as a linked list of chunks allocated from the heap. - - -- +------------------+ - -- | Next | - -- +------------------+ - -- | | Last (200) - -- | | - -- | | - -- | | - -- | | - -- | | - -- | | First (101) - -- +------------------+ - -- +----------> | | | - -- | +----------+-------+ - -- | | | - -- | ^ V - -- | | | - -- | +-------+----------+ - -- | | | | - -- | +------------------+ - -- | | | Last (100) - -- | | C | - -- | | H | - -- +-----------------+ | +-------->| U | - -- | Current_Chunk -|--+ | | N | - -- +-----------------+ | | K | - -- | Top -|-----+ | | First (1) - -- +-----------------+ +------------------+ - -- | Default_Size | | Prev | - -- +-----------------+ +------------------+ - -- - - type Chunk_Id (First, Last : SS_Ptr); - type Chunk_Ptr is access all Chunk_Id; - - type Chunk_Id (First, Last : SS_Ptr) is record - Prev, Next : Chunk_Ptr; - Mem : Memory (First .. Last); - end record; - - type Stack_Id is record - Top : SS_Ptr; - Default_Size : SSE.Storage_Count; - Current_Chunk : Chunk_Ptr; - end record; - - type Stack_Ptr is access Stack_Id; - -- Pointer to record used to represent a dynamically allocated secondary - -- stack descriptor for a secondary stack chunk. - - procedure Free is new Ada.Unchecked_Deallocation (Chunk_Id, Chunk_Ptr); - -- Free a dynamically allocated chunk - - function To_Stack_Ptr is new - Ada.Unchecked_Conversion (Address, Stack_Ptr); - function To_Addr is new - Ada.Unchecked_Conversion (Stack_Ptr, Address); - -- Convert to and from address stored in task data structures - - -------------------------------------------------------------- - -- Data Structures for Statically Allocated Secondary Stack -- - -------------------------------------------------------------- - - -- For the static case, the secondary stack is a single contiguous - -- chunk of storage, carved out of the primary stack, and represented - -- by the following data structure - - type Fixed_Stack_Id is record - Top : SS_Ptr; - -- Index of next available location in Mem. This is initialized to - -- 0, and then incremented on Allocate, and Decremented on Release. - - Last : SS_Ptr; - -- Length of usable Mem array, which is thus the index past the - -- last available location in Mem. Mem (Last-1) can be used. This - -- is used to check that the stack does not overflow. - - Max : SS_Ptr; - -- Maximum value of Top. Initialized to 0, and then may be incremented - -- on Allocate, but is never Decremented. The last used location will - -- be Mem (Max - 1), so Max is the maximum count of used stack space. - - Mem : Memory (0 .. 0); - -- This is the area that is actually used for the secondary stack. - -- Note that the upper bound is a dummy value properly defined by - -- the value of Last. We never actually allocate objects of type - -- Fixed_Stack_Id, so the bounds declared here do not matter. - end record; - - Dummy_Fixed_Stack : Fixed_Stack_Id; - pragma Warnings (Off, Dummy_Fixed_Stack); - -- Well it is not quite true that we never allocate an object of the - -- type. This dummy object is allocated for the purpose of getting the - -- offset of the Mem field via the 'Position attribute (such a nuisance - -- that we cannot apply this to a field of a type!) - - type Fixed_Stack_Ptr is access Fixed_Stack_Id; - -- Pointer to record used to describe statically allocated sec stack - - function To_Fixed_Stack_Ptr is new - Ada.Unchecked_Conversion (Address, Fixed_Stack_Ptr); - -- Convert from address stored in task data structures - - -------------- - -- Allocate -- - -------------- - - procedure SS_Allocate - (Addr : out Address; - Storage_Size : SSE.Storage_Count) - is - Max_Align : constant SS_Ptr := SS_Ptr (Standard'Maximum_Alignment); - Max_Size : constant SS_Ptr := - ((SS_Ptr (Storage_Size) + Max_Align - 1) / Max_Align) - * Max_Align; - - begin - -- Case of fixed allocation secondary stack - - if not SS_Ratio_Dynamic then - declare - Fixed_Stack : constant Fixed_Stack_Ptr := - To_Fixed_Stack_Ptr (SSL.Get_Sec_Stack_Addr.all); - - begin - -- Check if max stack usage is increasing - - if Fixed_Stack.Top + Max_Size > Fixed_Stack.Max then - - -- If so, check if max size is exceeded - - if Fixed_Stack.Top + Max_Size > Fixed_Stack.Last then - raise Storage_Error; - end if; - - -- Record new max usage - - Fixed_Stack.Max := Fixed_Stack.Top + Max_Size; - end if; - - -- Set resulting address and update top of stack pointer - - Addr := Fixed_Stack.Mem (Fixed_Stack.Top)'Address; - Fixed_Stack.Top := Fixed_Stack.Top + Max_Size; - end; - - -- Case of dynamically allocated secondary stack - - else - declare - Stack : constant Stack_Ptr := - To_Stack_Ptr (SSL.Get_Sec_Stack_Addr.all); - Chunk : Chunk_Ptr; - - To_Be_Released_Chunk : Chunk_Ptr; - - begin - Chunk := Stack.Current_Chunk; - - -- The Current_Chunk may not be the good one if a lot of release - -- operations have taken place. So go down the stack if necessary - - while Chunk.First > Stack.Top loop - Chunk := Chunk.Prev; - end loop; - - -- Find out if the available memory in the current chunk is - -- sufficient, if not, go to the next one and eventually create - -- the necessary room. - - while Chunk.Last - Stack.Top + 1 < Max_Size loop - if Chunk.Next /= null then - - -- Release unused non-first empty chunk - - if Chunk.Prev /= null and then Chunk.First = Stack.Top then - To_Be_Released_Chunk := Chunk; - Chunk := Chunk.Prev; - Chunk.Next := To_Be_Released_Chunk.Next; - To_Be_Released_Chunk.Next.Prev := Chunk; - Free (To_Be_Released_Chunk); - end if; - - -- Create new chunk of default size unless it is not - -- sufficient to satisfy the current request. - - elsif SSE.Storage_Count (Max_Size) <= Stack.Default_Size then - Chunk.Next := - new Chunk_Id - (First => Chunk.Last + 1, - Last => Chunk.Last + SS_Ptr (Stack.Default_Size)); - - Chunk.Next.Prev := Chunk; - - -- Otherwise create new chunk of requested size - - else - Chunk.Next := - new Chunk_Id - (First => Chunk.Last + 1, - Last => Chunk.Last + Max_Size); - - Chunk.Next.Prev := Chunk; - end if; - - Chunk := Chunk.Next; - Stack.Top := Chunk.First; - end loop; - - -- Resulting address is the address pointed by Stack.Top - - Addr := Chunk.Mem (Stack.Top)'Address; - Stack.Top := Stack.Top + Max_Size; - Stack.Current_Chunk := Chunk; - end; - end if; - end SS_Allocate; - - ------------- - -- SS_Free -- - ------------- - - procedure SS_Free (Stk : in out Address) is - begin - -- Case of statically allocated secondary stack, nothing to free - - if not SS_Ratio_Dynamic then - return; - - -- Case of dynamically allocated secondary stack - - else - declare - Stack : Stack_Ptr := To_Stack_Ptr (Stk); - Chunk : Chunk_Ptr; - - procedure Free is - new Ada.Unchecked_Deallocation (Stack_Id, Stack_Ptr); - - begin - Chunk := Stack.Current_Chunk; - - while Chunk.Prev /= null loop - Chunk := Chunk.Prev; - end loop; - - while Chunk.Next /= null loop - Chunk := Chunk.Next; - Free (Chunk.Prev); - end loop; - - Free (Chunk); - Free (Stack); - Stk := Null_Address; - end; - end if; - end SS_Free; - - ---------------- - -- SS_Get_Max -- - ---------------- - - function SS_Get_Max return Long_Long_Integer is - begin - if SS_Ratio_Dynamic then - return -1; - else - declare - Fixed_Stack : constant Fixed_Stack_Ptr := - To_Fixed_Stack_Ptr (SSL.Get_Sec_Stack_Addr.all); - begin - return Long_Long_Integer (Fixed_Stack.Max); - end; - end if; - end SS_Get_Max; - - ------------- - -- SS_Info -- - ------------- - - procedure SS_Info is - begin - Put_Line ("Secondary Stack information:"); - - -- Case of fixed secondary stack - - if not SS_Ratio_Dynamic then - declare - Fixed_Stack : constant Fixed_Stack_Ptr := - To_Fixed_Stack_Ptr (SSL.Get_Sec_Stack_Addr.all); - - begin - Put_Line ( - " Total size : " - & SS_Ptr'Image (Fixed_Stack.Last) - & " bytes"); - - Put_Line ( - " Current allocated space : " - & SS_Ptr'Image (Fixed_Stack.Top - 1) - & " bytes"); - end; - - -- Case of dynamically allocated secondary stack - - else - declare - Stack : constant Stack_Ptr := - To_Stack_Ptr (SSL.Get_Sec_Stack_Addr.all); - Nb_Chunks : Integer := 1; - Chunk : Chunk_Ptr := Stack.Current_Chunk; - - begin - while Chunk.Prev /= null loop - Chunk := Chunk.Prev; - end loop; - - while Chunk.Next /= null loop - Nb_Chunks := Nb_Chunks + 1; - Chunk := Chunk.Next; - end loop; - - -- Current Chunk information - - Put_Line ( - " Total size : " - & SS_Ptr'Image (Chunk.Last) - & " bytes"); - - Put_Line ( - " Current allocated space : " - & SS_Ptr'Image (Stack.Top - 1) - & " bytes"); - - Put_Line ( - " Number of Chunks : " - & Integer'Image (Nb_Chunks)); - - Put_Line ( - " Default size of Chunks : " - & SSE.Storage_Count'Image (Stack.Default_Size)); - end; - end if; - end SS_Info; - - ------------- - -- SS_Init -- - ------------- - - procedure SS_Init - (Stk : in out Address; - Size : Natural := Default_Secondary_Stack_Size) - is - begin - -- Case of fixed size secondary stack - - if not SS_Ratio_Dynamic then - declare - Fixed_Stack : constant Fixed_Stack_Ptr := - To_Fixed_Stack_Ptr (Stk); - - begin - Fixed_Stack.Top := 0; - Fixed_Stack.Max := 0; - - if Size < Dummy_Fixed_Stack.Mem'Position then - Fixed_Stack.Last := 0; - else - Fixed_Stack.Last := - SS_Ptr (Size) - Dummy_Fixed_Stack.Mem'Position; - end if; - end; - - -- Case of dynamically allocated secondary stack - - else - declare - Stack : Stack_Ptr; - begin - Stack := new Stack_Id; - Stack.Current_Chunk := new Chunk_Id (1, SS_Ptr (Size)); - Stack.Top := 1; - Stack.Default_Size := SSE.Storage_Count (Size); - Stk := To_Addr (Stack); - end; - end if; - end SS_Init; - - ------------- - -- SS_Mark -- - ------------- - - function SS_Mark return Mark_Id is - Sstk : constant System.Address := SSL.Get_Sec_Stack_Addr.all; - begin - if SS_Ratio_Dynamic then - return (Sstk => Sstk, Sptr => To_Stack_Ptr (Sstk).Top); - else - return (Sstk => Sstk, Sptr => To_Fixed_Stack_Ptr (Sstk).Top); - end if; - end SS_Mark; - - ---------------- - -- SS_Release -- - ---------------- - - procedure SS_Release (M : Mark_Id) is - begin - if SS_Ratio_Dynamic then - To_Stack_Ptr (M.Sstk).Top := M.Sptr; - else - To_Fixed_Stack_Ptr (M.Sstk).Top := M.Sptr; - end if; - end SS_Release; - - ------------------------- - -- Package Elaboration -- - ------------------------- - - -- Allocate a secondary stack for the main program to use - - -- We make sure that the stack has maximum alignment. Some systems require - -- this (e.g. Sparc), and in any case it is a good idea for efficiency. - - Stack : aliased Stack_Id; - for Stack'Alignment use Standard'Maximum_Alignment; - - Static_Secondary_Stack_Size : constant := 10 * 1024; - -- Static_Secondary_Stack_Size must be static so that Chunk is allocated - -- statically, and not via dynamic memory allocation. - - Chunk : aliased Chunk_Id (1, Static_Secondary_Stack_Size); - for Chunk'Alignment use Standard'Maximum_Alignment; - -- Default chunk used, unless gnatbind -D is specified with a value - -- greater than Static_Secondary_Stack_Size - -begin - declare - Chunk_Address : Address; - Chunk_Access : Chunk_Ptr; - - begin - if Default_Secondary_Stack_Size <= Static_Secondary_Stack_Size then - - -- Normally we allocate the secondary stack for the main program - -- statically, using the default secondary stack size. - - Chunk_Access := Chunk'Access; - - else - -- Default_Secondary_Stack_Size was increased via gnatbind -D, so we - -- need to allocate a chunk dynamically. - - Chunk_Access := - new Chunk_Id (1, SS_Ptr (Default_Secondary_Stack_Size)); - end if; - - if SS_Ratio_Dynamic then - Stack.Top := 1; - Stack.Current_Chunk := Chunk_Access; - Stack.Default_Size := - SSE.Storage_Offset (Default_Secondary_Stack_Size); - System.Soft_Links.Set_Sec_Stack_Addr_NT (Stack'Address); - - else - Chunk_Address := Chunk_Access.all'Address; - SS_Init (Chunk_Address, Default_Secondary_Stack_Size); - System.Soft_Links.Set_Sec_Stack_Addr_NT (Chunk_Address); - end if; - end; -end System.Secondary_Stack; |