* common/gcc12/environment_task.adb: if the link includes a symbol

simonjwright · simonjwright · commit f04cbf758a2d · 2022-11-02T18:21:04.000Z
_environment_task_secondary_stack_size, use this as the stack size:
      otherwise, use the default (see System.Parameters).
      If it is specified, allocate as much space as required (including
      that for the header info in an SS_Stack) using System.Memory.
      The usual case for setting the size may well be when a secondary
      stack isn't required; you would have thought we could create a single
      instance and use that, but this package can't use elaboration code
      (it actually performs elaboration! when Environment_Task calls
      main).
  * common/gnat-ce-2020/environment_task.adb: likewise.
  * common/gcc12/s-tarest.adb (Create_Restricted_Task): new block
      Calculate_Secondary_Stack_Size. Checks configuration issues:
      o if the address is null, the secondary stack is to be carved out
        of the primary stack; check it's less (this can happen if the
        Default_Secondary_Stack_Size is specified, see System.Parameters).
      o If the address isn't null, the size must be specified.
  * common/gnat-ce-2020/s-tarest.adb: likewise.
diff --git a/common/gcc12/environment_task.adb b/common/gcc12/environment_task.adb
@@ -1,4 +1,4 @@
---  Copyright (C) 2016-2018 Free Software Foundation, Inc.
+--  Copyright (C) 2016-2022 Free Software Foundation, Inc.
 --
 --  This file is part of the Cortex GNAT RTS project. This file is
 --  free software; you can redistribute it and/or modify it under
@@ -18,7 +18,10 @@
 --  program; see the files COPYING3 and COPYING.RUNTIME respectively.
 --  If not, see <http://www.gnu.org/licenses/>.
 
+with System.Address_To_Access_Conversions;
+with System.Memory;
 with System.Parameters;
+with System.Secondary_Stack;
 with System.Tasking.Restricted.Stages;
 with System.Task_Info;
 
@@ -54,22 +57,70 @@ package body Environment_Task is
      External_Name => "_environment_task_storage_size";
    pragma Weak_External (Environment_Task_Storage_Size);
 
+   --  If the link includes a symbol _environment_task_secondary_stack_size,
+   --  use this as the storage size: otherwise, use the default (10%
+   --  of the task storage size).
+   Environment_Task_Secondary_Stack_Size : constant System.Parameters.Size_Type
+   with
+     Import,
+     Convention => Ada,
+     External_Name => "_environment_task_secondary_stack_size";
+   pragma Weak_External (Environment_Task_Secondary_Stack_Size);
+
    procedure Create is
       --  Will be overwritten by binder-generated code if the main
       --  program has pragma Priority.
       Main_Priority : Integer;
       pragma Import (C, Main_Priority, "__gl_main_priority");
+
+      --  Handling the secondary stack size & allocation; these are
+      --  the default settings, the secondary stack is allocated from
+      --  the task stack.
+      Sec_Stack_Address : System.Address := System.Null_Address;
+      Sec_Stack_Size : System.Parameters.Size_Type
+        := System.Parameters.Unspecified_Size;
+
+      --  A secondary stack of size s consists of management data
+      --  followed by s bytes of actual stack.
+      subtype Null_Secondary_Stack is System.Secondary_Stack.SS_Stack (0);
+      Basic_Secondary_Stack_Size : constant System.Parameters.Size_Type
+        := Null_Secondary_Stack'Max_Size_In_Storage_Elements;
+
+      package Stack_Address_Conversions
+      is new System.Address_To_Access_Conversions
+        (Object => System.Secondary_Stack.SS_Stack);
+
       use type System.Address;
+      use type System.Parameters.Size_Type;
    begin
+      --  If the secondary stack size is specified, allocate it (in
+      --  heap; the compiler would have allocated it in BSS for a
+      --  source-language task).
+      if Environment_Task_Secondary_Stack_Size'Address /=
+        System.Null_Address
+      then
+         Sec_Stack_Size := Environment_Task_Secondary_Stack_Size;
+         Sec_Stack_Address
+           := System.Memory.Alloc
+             (System.Memory.size_t (Sec_Stack_Size
+                                      + Basic_Secondary_Stack_Size));
+         if Sec_Stack_Address = System.Null_Address then
+            raise Storage_Error with
+              "couldn't allocate secondary stack for environment task";
+         end if;
+      end if;
+
       System.Tasking.Restricted.Stages.Create_Restricted_Task
         (Priority             => Main_Priority,
          Stack_Address        => System.Null_Address,
          Size                 =>
            (if Environment_Task_Storage_Size'Address = System.Null_Address
             then 1536
             else Environment_Task_Storage_Size),
-         Sec_Stack_Address    => null,
-         Secondary_Stack_Size => System.Parameters.Unspecified_Size,
+         Sec_Stack_Address    =>
+           Stack_Address_Conversions.To_Pointer (Sec_Stack_Address)
+             .all'Unchecked_Access,
+         Secondary_Stack_Size => Sec_Stack_Size,
          Task_Info            => System.Task_Info.Unspecified_Task_Info,
          CPU                  => System.Tasking.Unspecified_CPU,
          State                => Environment_Task'Access,
diff --git a/common/gcc12/s-tarest.adb b/common/gcc12/s-tarest.adb
@@ -6,7 +6,7 @@
 --                                                                          --
 --                                  B o d y                                 --
 --                                                                          --
---      Copyright (C) 2016-2018, 2020 Free Software Foundation, Inc.        --
+--         Copyright (C) 2016-2022 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- --
@@ -138,16 +138,50 @@ package body System.Tasking.Restricted.Stages is
 
       Actual_Stack_Size : constant System.Parameters.Size_Type :=
         System.Parameters.Adjust_Storage_Size (Size);
+      Actual_Secondary_Stack_Size : System.Parameters.Size_Type;
 
       Wrapper_Parameter_Address : constant System.Address :=
         Memory.Alloc (Parameters'Max_Size_In_Storage_Elements);
       Wrapper_Parameter_Access :
         constant Parameters_Conversion.Object_Pointer :=
         Parameters_Conversion.To_Pointer (Wrapper_Parameter_Address);
 
-      use type System.Parameters.Size_Type;
       use type FreeRTOS.Tasks.Task_Handle;
    begin
+
+      Calculate_Secondary_Stack_Size :
+      declare
+         use type System.Secondary_Stack.SS_Stack_Ptr;
+         use type System.Parameters.Size_Type;
+      begin
+         if Sec_Stack_Address = null then
+            if Secondary_Stack_Size = System.Parameters.Unspecified_Size
+            then
+               --  The Default_Secondary_Stack_Size if non-zero, or
+               --  10% of the task's stack size
+               Actual_Secondary_Stack_Size :=
+                 System.Parameters.Secondary_Stack_Size (Actual_Stack_Size);
+               if Actual_Secondary_Stack_Size > Actual_Stack_Size then
+                  raise Program_Error with
+                    "secondary stack larger than primary stack";
+               end if;
+            else
+               raise Program_Error with
+                 "compiler should have allocated secondary stack";
+            end if;
+         else
+            --  The programmer has specified the secondary stack size,
+            --  and the compiler has allocated space for it in BSS
+            if Secondary_Stack_Size = System.Parameters.Unspecified_Size
+            then
+               raise Program_Error with
+                 "compiler should have specified secondary stack size";
+            else
+               Actual_Secondary_Stack_Size := Secondary_Stack_Size;
+            end if;
+         end if;
+      end Calculate_Secondary_Stack_Size;
+
       if Wrapper_Parameter_Address = System.Null_Address then
          raise Storage_Error with "couldn't allocate task wrapper";
       end if;
@@ -156,10 +190,7 @@ package body System.Tasking.Restricted.Stages is
          Task_Proc     => State,
          Discriminants => Discriminants,
          SStack_Addr   => Sec_Stack_Address,
-         SStack_Size   =>
-           (if Secondary_Stack_Size = System.Parameters.Unspecified_Size
-            then System.Parameters.Secondary_Stack_Size (Actual_Stack_Size)
-            else Secondary_Stack_Size));  -- don't think this will happen?
+         SStack_Size   => Actual_Secondary_Stack_Size);
 
       Created_Task.Common.Base_Priority := (if Priority = Unspecified_Priority
                                             then System.Default_Priority
diff --git a/common/gnat-ce-2020/environment_task.adb b/common/gnat-ce-2020/environment_task.adb
@@ -1,4 +1,4 @@
---  Copyright (C) 2016-2018 Free Software Foundation, Inc.
+--  Copyright (C) 2016-2022 Free Software Foundation, Inc.
 --
 --  This file is part of the Cortex GNAT RTS project. This file is
 --  free software; you can redistribute it and/or modify it under
@@ -18,7 +18,10 @@
 --  program; see the files COPYING3 and COPYING.RUNTIME respectively.
 --  If not, see <http://www.gnu.org/licenses/>.
 
+with System.Address_To_Access_Conversions;
+with System.Memory;
 with System.Parameters;
+with System.Secondary_Stack;
 with System.Tasking.Restricted.Stages;
 with System.Task_Info;
 
@@ -54,22 +57,70 @@ package body Environment_Task is
      External_Name => "_environment_task_storage_size";
    pragma Weak_External (Environment_Task_Storage_Size);
 
+   --  If the link includes a symbol _environment_task_secondary_stack_size,
+   --  use this as the storage size: otherwise, use the default (10%
+   --  of the task storage size).
+   Environment_Task_Secondary_Stack_Size : constant System.Parameters.Size_Type
+   with
+     Import,
+     Convention => Ada,
+     External_Name => "_environment_task_secondary_stack_size";
+   pragma Weak_External (Environment_Task_Secondary_Stack_Size);
+
    procedure Create is
       --  Will be overwritten by binder-generated code if the main
       --  program has pragma Priority.
       Main_Priority : Integer;
       pragma Import (C, Main_Priority, "__gl_main_priority");
+
+      --  Handling the secondary stack size & allocation; these are
+      --  the default settings, the secondary stack is allocated from
+      --  the task stack.
+      Sec_Stack_Address : System.Address := System.Null_Address;
+      Sec_Stack_Size : System.Parameters.Size_Type
+        := System.Parameters.Unspecified_Size;
+
+      --  A secondary stack of size s consists of management data
+      --  followed by s bytes of actual stack.
+      subtype Null_Secondary_Stack is System.Secondary_Stack.SS_Stack (0);
+      Basic_Secondary_Stack_Size : constant System.Parameters.Size_Type
+        := Null_Secondary_Stack'Max_Size_In_Storage_Elements;
+
+      package Stack_Address_Conversions
+      is new System.Address_To_Access_Conversions
+        (Object => System.Secondary_Stack.SS_Stack);
+
       use type System.Address;
+      use type System.Parameters.Size_Type;
    begin
+      --  If the secondary stack size is specified, allocate it (in
+      --  heap; the compiler would have allocated it in BSS for a
+      --  source-language task).
+      if Environment_Task_Secondary_Stack_Size'Address /=
+        System.Null_Address
+      then
+         Sec_Stack_Size := Environment_Task_Secondary_Stack_Size;
+         Sec_Stack_Address
+           := System.Memory.Alloc
+             (System.Memory.size_t (Sec_Stack_Size
+                                      + Basic_Secondary_Stack_Size));
+         if Sec_Stack_Address = System.Null_Address then
+            raise Storage_Error with
+              "couldn't allocate secondary stack for environment task";
+         end if;
+      end if;
+
       System.Tasking.Restricted.Stages.Create_Restricted_Task
         (Priority             => Main_Priority,
          Stack_Address        => System.Null_Address,
          Size                 =>
            (if Environment_Task_Storage_Size'Address = System.Null_Address
             then 1536
             else Environment_Task_Storage_Size),
-         Sec_Stack_Address    => null,
-         Secondary_Stack_Size => System.Parameters.Unspecified_Size,
+         Sec_Stack_Address    =>
+           Stack_Address_Conversions.To_Pointer (Sec_Stack_Address)
+             .all'Unchecked_Access,
+         Secondary_Stack_Size => Sec_Stack_Size,
          Task_Info            => System.Task_Info.Unspecified_Task_Info,
          CPU                  => System.Tasking.Unspecified_CPU,
          State                => Environment_Task'Access,
diff --git a/common/gnat-ce-2020/s-tarest.adb b/common/gnat-ce-2020/s-tarest.adb
@@ -6,7 +6,7 @@
 --                                                                          --
 --                                  B o d y                                 --
 --                                                                          --
---      Copyright (C) 2016-2018, 2020 Free Software Foundation, Inc.        --
+--         Copyright (C) 2016-2022 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- --
@@ -138,16 +138,50 @@ package body System.Tasking.Restricted.Stages is
 
       Actual_Stack_Size : constant System.Parameters.Size_Type :=
         System.Parameters.Adjust_Storage_Size (Size);
+      Actual_Secondary_Stack_Size : System.Parameters.Size_Type;
 
       Wrapper_Parameter_Address : constant System.Address :=
         Memory.Alloc (Parameters'Max_Size_In_Storage_Elements);
       Wrapper_Parameter_Access :
         constant Parameters_Conversion.Object_Pointer :=
         Parameters_Conversion.To_Pointer (Wrapper_Parameter_Address);
 
-      use type System.Parameters.Size_Type;
       use type FreeRTOS.Tasks.Task_Handle;
    begin
+
+      Calculate_Secondary_Stack_Size :
+      declare
+         use type System.Secondary_Stack.SS_Stack_Ptr;
+         use type System.Parameters.Size_Type;
+      begin
+         if Sec_Stack_Address = null then
+            if Secondary_Stack_Size = System.Parameters.Unspecified_Size
+            then
+               --  The Default_Secondary_Stack_Size if non-zero, or
+               --  10% of the task's stack size
+               Actual_Secondary_Stack_Size :=
+                 System.Parameters.Secondary_Stack_Size (Actual_Stack_Size);
+               if Actual_Secondary_Stack_Size > Actual_Stack_Size then
+                  raise Program_Error with
+                    "secondary stack larger than primary stack";
+               end if;
+            else
+               raise Program_Error with
+                 "compiler should have allocated secondary stack";
+            end if;
+         else
+            --  The programmer has specified the secondary stack size,
+            --  and the compiler has allocated space for it in BSS
+            if Secondary_Stack_Size = System.Parameters.Unspecified_Size
+            then
+               raise Program_Error with
+                 "compiler should have specified secondary stack size";
+            else
+               Actual_Secondary_Stack_Size := Secondary_Stack_Size;
+            end if;
+         end if;
+      end Calculate_Secondary_Stack_Size;
+
       if Wrapper_Parameter_Address = System.Null_Address then
          raise Storage_Error with "couldn't allocate task wrapper";
       end if;
@@ -156,10 +190,7 @@ package body System.Tasking.Restricted.Stages is
          Task_Proc     => State,
          Discriminants => Discriminants,
          SStack_Addr   => Sec_Stack_Address,
-         SStack_Size   =>
-           (if Secondary_Stack_Size = System.Parameters.Unspecified_Size
-            then System.Parameters.Secondary_Stack_Size (Actual_Stack_Size)
-            else Secondary_Stack_Size));  -- don't think this will happen?
+         SStack_Size   => Actual_Secondary_Stack_Size);
 
       Created_Task.Common.Base_Priority := (if Priority = Unspecified_Priority
                                             then System.Default_Priority
