1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
|
-- GHDL Run Time (GRT) - process stacks.
-- Copyright (C) 2002 - 2014 Tristan Gingold
--
-- GHDL is free software; you can redistribute it and/or modify it under
-- the terms of the GNU General Public License as published by the Free
-- Software Foundation; either version 2, or (at your option) any later
-- version.
--
-- GHDL is distributed in the hope that it will be useful, but WITHOUT 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
-- along with GCC; see the file COPYING. If not, write to the Free
-- Software Foundation, 59 Temple Place - Suite 330, Boston, MA
-- 02111-1307, 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.
with System; use System;
with Ada.Unchecked_Conversion;
package Grt.Stacks is
-- Instance is the parameter of the process procedure.
-- This is in fact a fully opaque type whose content is private to the
-- process.
type Instance is limited private;
type Instance_Acc is access all Instance;
pragma Convention (C, Instance_Acc);
-- A process is identified by a procedure having a single private
-- parameter (its instance).
type Proc_Acc is access procedure (Self : Instance_Acc);
pragma Convention (C, Proc_Acc);
function To_Address is new Ada.Unchecked_Conversion
(Instance_Acc, System.Address);
type Stack_Type is new Address;
Null_Stack : constant Stack_Type := Stack_Type (Null_Address);
-- Initialize the stacks package.
-- This may adjust stack sizes.
-- Must be called after grt.options.decode.
procedure Stack_Init;
-- Create a new stack, which on first execution will call FUNC with
-- an argument ARG.
function Stack_Create (Func : Proc_Acc; Arg : Instance_Acc)
return Stack_Type;
-- Resume stack TO and save the current context to the stack pointed by
-- CUR.
procedure Stack_Switch (To : Stack_Type; From : Stack_Type);
-- Delete stack STACK, which must not be currently executed.
procedure Stack_Delete (Stack : Stack_Type);
-- Error during stack handling:
-- Cannot grow the stack.
procedure Error_Grow_Failed;
pragma No_Return (Error_Grow_Failed);
-- Invalid memory access detected (other than dereferencing a NULL access).
procedure Error_Memory_Access;
pragma No_Return (Error_Memory_Access);
-- A NULL access is dereferenced.
procedure Error_Null_Access;
pragma No_Return (Error_Null_Access);
private
type Instance is null record;
pragma Import (C, Stack_Init, "grt_stack_init");
pragma Import (C, Stack_Create, "grt_stack_create");
pragma Import (C, Stack_Switch, "grt_stack_switch");
pragma Import (C, Stack_Delete, "grt_stack_delete");
pragma Export (C, Error_Grow_Failed, "grt_stack_error_grow_failed");
pragma Export (C, Error_Memory_Access, "grt_stack_error_memory_access");
pragma Export (C, Error_Null_Access, "grt_stack_error_null_access");
end Grt.Stacks;
|