2008-04-08 Eric Botcazou <ebotcazou@adacore.com>

	    Arnaud Charlet  <charlet@adacore.com>

	* s-osinte-linux-alpha.ads, s-osinte-linux-hppa.ads: Removed.

	s-taspri-posix-noaltstack.ads, s-linux.ads, s-linux-alpha.ads,
	s-linux-hppa.ads: New files. Disable alternate stack on ia64-hpux.

	* s-osinte-lynxos-3.ads,
	(Alternate_Stack): Remove when not needed. Simplify declaration
	otherwise.
	(Alternate_Stack_Size): New constant.

	s-osinte-mingw.ads, s-taprop-mingw.adb: Code clean up: avoid use of
	'Unrestricted_Access.

	* s-osinte-hpux.ads, s-osinte-solaris-posix.ads, s-osinte-aix.ads,
	s-osinte-lynxos.ads, s-osinte-freebsd.ads s-osinte-darwin.ads,
	s-osinte-tru64.ads, s-osinte-irix.ads, s-osinte-linux.ads,
	s-osinte-solaris.ads, s-osinte-vms.ads
	(SA_ONSTACK): New constant.
	(stack_t): New record type.
	(sigaltstack): New imported function.
	(Alternate_Stack): New imported variable.
	(Alternate_Stack_Size): New constant.

	* system-linux-x86_64.ads: (Stack_Check_Probes): Set to True.

	* s-taspri-lynxos.ads, s-taspri-solaris.ads, s-taspri-tru64.ads,
	s-taspri-hpux-dce.ads (Task_Address): New subtype of System.Address
	(Task_Address_Size): New constant size of System.Address
	(Alternate_Stack_Size): New constant.

	* s-taprop-posix.adb, s-taprop-linux.adb (Get_Stack_Attributes): Delete.
	(Enter_Task): Do not notify stack to System.Stack_Checking.Operations.
	Establish the alternate stack if the platform makes use of n alternate
	signal stack for stack overflows.
	(Create_Task): Take into account the alternate stack in the stack size.
	(Initialize): Save the address of the alternate stack into the ATCB for
	the environment task.
	(Create_Task): Fix assertions for NPTL library (vs old LinuxThreads).

	* s-parame.adb (Minimum_Stack_Size): Increase value to 16K to

	* system-linux-x86.ads: (Stack_Check_Probes): Set to True.

	* s-intman-posix.adb: 
	(Initialize): Set SA_ONSTACK for SIGSEGV if the platform makes use of an
	alternate signal stack for stack overflows.

	* init.c (__gnat_adjust_context_for_raise, Linux version): On i386 and
	x86-64, adjust the saved value of the stack pointer if the signal was
	raised by a stack checking probe.
	(HP-UX section): Use global __gnat_alternate_stack as signal handler
	stack and only for SIGSEGV.
	(Linux section): Likewise on x86 and x86-64.
	[VxWorks section]
	(__gnat_map_signal): Now static.
	(__gnat_error_handler): Not static any more.
	(__gnat_adjust_context_for_raise): New function. Signal context
	adjustment for PPC && !VTHREADS && !RTP, as required by the zcx
	propagation circuitry.
	(__gnat_error_handler): Second argument of a sigaction handler is a
	pointer, not an int, and is unused.
	Adjust signal context before mapping to exception.
	Install signal handlers for LynxOS case.

	* s-taskin.ads (Common_ATCB): New field Task_Alternate_Stack.
	(Task_Id): Set size to Task_Address_Size
	(To_Task_id): Unchecked convert from Task_Address vice System.Address
	(To_Address): Unchecked convert to Task_Address vice System.Address

	* s-tassta.adb (Task_Wrapper): Define the alternate stack and save its
	address into the ATCB if the platform makes use of an alternate signal
	stack for stack overflows.
	(Free_Task): Add call to Finalize_Attributes_Link.
	Add argument Relative_Deadline to pass the value specified for
	the task. This is not yet used for any target.

	* s-tassta.ads (Create_Task): Add argument Relative_Deadline to pass
	the value specified for the task.



git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@134004 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 32 insertions, 72 deletions

diff --git a/gcc/ada/s-taprop-linux.adb b/gcc/ada/s-taprop-linux.adb
index 6c64f341eec..a4bc9495719 100644
--- a/gcc/ada/s-taprop-linux.adb
+++ b/gcc/ada/s-taprop-linux.adb
@@ -49,7 +49,6 @@ with System.Task_Info;
 with System.Tasking.Debug;
 with System.Interrupt_Management;
 with System.OS_Primitives;
-with System.Storage_Elements;
 with System.Stack_Checking.Operations;
 
 with System.Soft_Links;
@@ -69,9 +68,11 @@ package body System.Task_Primitives.Operations is
    use System.OS_Interface;
    use System.Parameters;
    use System.OS_Primitives;
-   use System.Storage_Elements;
    use System.Task_Info;
 
+   Use_Alternate_Stack : constant Boolean := Alternate_Stack_Size /= 0;
+   --  Whether to use an alternate signal stack for stack overflows
+
    ----------------
    -- Local Data --
    ----------------
@@ -161,13 +162,6 @@ package body System.Task_Primitives.Operations is
    function To_pthread_t is new Ada.Unchecked_Conversion
      (unsigned_long, System.OS_Interface.pthread_t);
 
-   procedure Get_Stack_Attributes
-     (T    : Task_Id;
-      ISP  : out System.Address;
-      Size : out Storage_Offset);
-   --  Fill ISP and Size with the Initial Stack Pointer value and the
-   --  thread stack size for task T.
-
    -------------------
    -- Abort_Handler --
    -------------------
@@ -696,50 +690,6 @@ package body System.Task_Primitives.Operations is
       return T.Common.Current_Priority;
    end Get_Priority;
 
-   --------------------------
-   -- Get_Stack_Attributes --
-   --------------------------
-
-   procedure Get_Stack_Attributes
-     (T    : Task_Id;
-      ISP  : out System.Address;
-      Size : out Storage_Offset)
-   is
-      function pthread_getattr_np
-        (thread : pthread_t;
-         attr   : System.Address) return Interfaces.C.int;
-      pragma Import (C, pthread_getattr_np, "pthread_getattr_np");
-
-      function pthread_attr_getstack
-        (attr : System.Address;
-         base : System.Address;
-         size : System.Address) return Interfaces.C.int;
-      pragma Import (C, pthread_attr_getstack, "pthread_attr_getstack");
-
-      Result : Interfaces.C.int;
-
-      Attributes : aliased pthread_attr_t;
-      Stack_Base : aliased System.Address;
-      Stack_Size : aliased Storage_Offset;
-
-   begin
-      Result :=
-        pthread_getattr_np
-          (T.Common.LL.Thread, Attributes'Address);
-      pragma Assert (Result = 0);
-
-      Result :=
-        pthread_attr_getstack
-          (Attributes'Address, Stack_Base'Address, Stack_Size'Address);
-      pragma Assert (Result = 0);
-
-      Result := pthread_attr_destroy (Attributes'Access);
-      pragma Assert (Result = 0);
-
-      ISP  := Stack_Base + Stack_Size;
-      Size := Stack_Size;
-   end Get_Stack_Attributes;
-
    ----------------
    -- Enter_Task --
    ----------------
@@ -747,8 +697,7 @@ package body System.Task_Primitives.Operations is
    procedure Enter_Task (Self_ID : Task_Id) is
    begin
       if Self_ID.Common.Task_Info /= null
-        and then
-          Self_ID.Common.Task_Info.CPU_Affinity = No_CPU
+        and then Self_ID.Common.Task_Info.CPU_Affinity = No_CPU
       then
          raise Invalid_CPU_Number;
       end if;
@@ -769,17 +718,18 @@ package body System.Task_Primitives.Operations is
 
       Unlock_RTS;
 
-      --  Determine where the task stack starts, how large it is, and let the
-      --  stack checking engine know about it.
-
-      declare
-         Initial_SP : System.Address;
-         Stack_Size : Storage_Offset;
-      begin
-         Get_Stack_Attributes (Self_ID, Initial_SP, Stack_Size);
-         System.Stack_Checking.Operations.Notify_Stack_Attributes
-           (Initial_SP, Stack_Size);
-      end;
+      if Use_Alternate_Stack then
+         declare
+            Stack  : aliased stack_t;
+            Result : Interfaces.C.int;
+         begin
+            Stack.ss_sp    := Self_ID.Common.Task_Alternate_Stack;
+            Stack.ss_size  := Alternate_Stack_Size;
+            Stack.ss_flags := 0;
+            Result := sigaltstack (Stack'Access, null);
+            pragma Assert (Result = 0);
+         end;
+      end if;
    end Enter_Task;
 
    --------------
@@ -864,10 +814,14 @@ package body System.Task_Primitives.Operations is
       Priority   : System.Any_Priority;
       Succeeded  : out Boolean)
    is
-      Attributes : aliased pthread_attr_t;
-      Result     : Interfaces.C.int;
+      Attributes          : aliased pthread_attr_t;
+      Adjusted_Stack_Size : Interfaces.C.size_t;
+      Result              : Interfaces.C.int;
 
    begin
+      Adjusted_Stack_Size :=
+         Interfaces.C.size_t (Stack_Size + Alternate_Stack_Size);
+
       Result := pthread_attr_init (Attributes'Access);
       pragma Assert (Result = 0 or else Result = ENOMEM);
 
@@ -878,7 +832,7 @@ package body System.Task_Primitives.Operations is
 
       Result :=
         pthread_attr_setstacksize
-          (Attributes'Access, Interfaces.C.size_t (Stack_Size));
+          (Attributes'Access, Adjusted_Stack_Size);
       pragma Assert (Result = 0);
 
       Result :=
@@ -896,7 +850,8 @@ package body System.Task_Primitives.Operations is
          Attributes'Access,
          Thread_Body_Access (Wrapper),
          To_Address (T));
-      pragma Assert (Result = 0 or else Result = EAGAIN);
+      pragma Assert
+        (Result = 0 or else Result = EAGAIN or else Result = ENOMEM);
 
       if Result /= 0 then
          Succeeded := False;
@@ -1148,8 +1103,7 @@ package body System.Task_Primitives.Operations is
          pragma Assert (Result = 0);
 
          SSL.Abort_Undefer.all;
-      end
-      if;
+      end if;
    end Suspend_Until_True;
 
    ----------------
@@ -1253,6 +1207,7 @@ package body System.Task_Primitives.Operations is
       old_act : aliased struct_sigaction;
       Tmp_Set : aliased sigset_t;
       Result  : Interfaces.C.int;
+      --  Whether to use an alternate signal stack for stack overflows
 
       function State
         (Int : System.Interrupt_Management.Interrupt_ID) return Character;
@@ -1297,6 +1252,11 @@ package body System.Task_Primitives.Operations is
 
       Specific.Initialize (Environment_Task);
 
+      if Use_Alternate_Stack then
+         Environment_Task.Common.Task_Alternate_Stack :=
+           Alternate_Stack'Address;
+      end if;
+
       Enter_Task (Environment_Task);
 
       --  Install the abort-signal handler