File : system-pikeos-arm-ravenscar-sfp.ads


   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                        GNAT RUN-TIME COMPONENTS                          --
   4 --                                                                          --
   5 --                               S Y S T E M                                --
   6 --                                                                          --
   7 --                                 S p e c                                  --
   8 --                          (PikeOS ARM Version)                            --
   9 --                                                                          --
  10 --          Copyright (C) 1992-2016, Free Software Foundation, Inc.         --
  11 --                                                                          --
  12 -- This specification is derived from the Ada Reference Manual for use with --
  13 -- GNAT. The copyright notice above, and the license provisions that follow --
  14 -- apply solely to the  contents of the part following the private keyword. --
  15 --                                                                          --
  16 -- GNAT is free software;  you can  redistribute it  and/or modify it under --
  17 -- terms of the  GNU General Public License as published  by the Free Soft- --
  18 -- ware  Foundation;  either version 3,  or (at your option) any later ver- --
  19 -- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
  20 -- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
  21 -- or FITNESS FOR A PARTICULAR PURPOSE.                                     --
  22 --                                                                          --
  23 --                                                                          --
  24 --                                                                          --
  25 --                                                                          --
  26 --                                                                          --
  27 -- You should have received a copy of the GNU General Public License and    --
  28 -- a copy of the GCC Runtime Library Exception along with this program;     --
  29 -- see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see    --
  30 -- <http://www.gnu.org/licenses/>.                                          --
  31 --                                                                          --
  32 -- GNAT was originally developed  by the GNAT team at  New York University. --
  33 -- Extensive contributions were provided by Ada Core Technologies Inc.      --
  34 --                                                                          --
  35 ------------------------------------------------------------------------------
  36 
  37 --  This is a Ravenscar sfp version of this package for ARM PikeOS targets
  38 
  39 pragma Restrictions (No_Exception_Propagation);
  40 --  Only local exception handling is supported in this profile
  41 
  42 pragma Restrictions (No_Exception_Registration);
  43 --  Disable exception name registration. This capability is not used because
  44 --  it is only required by exception stream attributes which are not supported
  45 --  in this run time.
  46 
  47 pragma Restrictions (No_Implicit_Dynamic_Code);
  48 --  Pointers to nested subprograms are not allowed in this run time, in order
  49 --  to prevent the compiler from building "trampolines".
  50 
  51 pragma Restrictions (No_Finalization);
  52 --  Controlled types are not supported in this run time
  53 
  54 pragma Profile (Ravenscar);
  55 --  This is a Ravenscar run time
  56 
  57 pragma Discard_Names;
  58 --  Disable explicitly the generation of names associated with entities in
  59 --  order to reduce the amount of storage used. These names are not used anyway
  60 --  (attributes such as 'Image and 'Value are not supported in this run time).
  61 
  62 package System is
  63    pragma Pure;
  64    --  Note that we take advantage of the implementation permission to make
  65    --  this unit Pure instead of Preelaborable; see RM 13.7.1(15). In Ada
  66    --  2005, this is Pure in any case (AI-362).
  67 
  68    pragma No_Elaboration_Code_All;
  69    --  Allow the use of that restriction in units that WITH this unit
  70 
  71    type Name is (SYSTEM_NAME_GNAT);
  72    System_Name : constant Name := SYSTEM_NAME_GNAT;
  73 
  74    --  System-Dependent Named Numbers
  75 
  76    Min_Int               : constant := Long_Long_Integer'First;
  77    Max_Int               : constant := Long_Long_Integer'Last;
  78 
  79    Max_Binary_Modulus    : constant := 2 ** Long_Long_Integer'Size;
  80    Max_Nonbinary_Modulus : constant := 2 ** Integer'Size - 1;
  81 
  82    Max_Base_Digits       : constant := Long_Long_Float'Digits;
  83    Max_Digits            : constant := Long_Long_Float'Digits;
  84 
  85    Max_Mantissa          : constant := 63;
  86    Fine_Delta            : constant := 2.0 ** (-Max_Mantissa);
  87 
  88    Tick                  : constant := 0.000_000_001; --  1 ns
  89 
  90    --  Storage-related Declarations
  91 
  92    type Address is private;
  93    pragma Preelaborable_Initialization (Address);
  94    Null_Address : constant Address;
  95 
  96    Storage_Unit : constant := 8;
  97    Word_Size    : constant := 32;
  98    Memory_Size  : constant := 2 ** 32;
  99 
 100    --  Address comparison
 101 
 102    function "<"  (Left, Right : Address) return Boolean;
 103    function "<=" (Left, Right : Address) return Boolean;
 104    function ">"  (Left, Right : Address) return Boolean;
 105    function ">=" (Left, Right : Address) return Boolean;
 106    function "="  (Left, Right : Address) return Boolean;
 107 
 108    pragma Import (Intrinsic, "<");
 109    pragma Import (Intrinsic, "<=");
 110    pragma Import (Intrinsic, ">");
 111    pragma Import (Intrinsic, ">=");
 112    pragma Import (Intrinsic, "=");
 113 
 114    --  Other System-Dependent Declarations
 115 
 116    type Bit_Order is (High_Order_First, Low_Order_First);
 117    Default_Bit_Order : constant Bit_Order := Low_Order_First;
 118    pragma Warnings (Off, Default_Bit_Order); -- kill constant condition warning
 119 
 120    --  Priority-related Declarations (RM D.1)
 121 
 122    --  For simplicity there is a 1-1 correspondence between Ada and PikeOS
 123    --  priorities. PikeOS priority 0 is reserved by the idle thread, so not
 124    --  available to Ada.
 125 
 126    --  PikeOS priorities are 0 .. 255
 127 
 128    --  Priorities greather than 245 are reserved to the system software (PSSW)
 129 
 130    --  This implementation reserves priorities 224-239 to interrupts
 131 
 132    --  Priorities 240-245 are reserved to HM and PikeOS exception handlers
 133 
 134    Max_Priority           : constant Positive := 223;
 135    Max_Interrupt_Priority : constant Positive := 239;
 136 
 137    subtype Any_Priority       is Integer range 1 .. Max_Interrupt_Priority;
 138    subtype Priority           is Any_Priority
 139      range Any_Priority'First .. Max_Priority;
 140    subtype Interrupt_Priority is Any_Priority
 141      range Priority'Last + 1 .. Any_Priority'Last;
 142 
 143    Default_Priority : constant Priority :=
 144                         (Priority'First + Priority'Last) / 2;
 145 
 146 private
 147 
 148    type Address is mod Memory_Size;
 149    Null_Address : constant Address := 0;
 150 
 151    --------------------------------------
 152    -- System Implementation Parameters --
 153    --------------------------------------
 154 
 155    --  These parameters provide information about the target that is used
 156    --  by the compiler. They are in the private part of System, where they
 157    --  can be accessed using the special circuitry in the Targparm unit
 158    --  whose source should be consulted for more detailed descriptions
 159    --  of the individual switch values.
 160 
 161    Atomic_Sync_Default       : constant Boolean := False;
 162    Backend_Divide_Checks     : constant Boolean := False;
 163    Backend_Overflow_Checks   : constant Boolean := True;
 164    Command_Line_Args         : constant Boolean := False;
 165    Configurable_Run_Time     : constant Boolean := True;
 166    Denorm                    : constant Boolean := True;
 167    Duration_32_Bits          : constant Boolean := False;
 168    Exit_Status_Supported     : constant Boolean := False;
 169    Fractional_Fixed_Ops      : constant Boolean := False;
 170    Frontend_Layout           : constant Boolean := False;
 171    Machine_Overflows         : constant Boolean := False;
 172    Machine_Rounds            : constant Boolean := True;
 173    Preallocated_Stacks       : constant Boolean := True;
 174    Signed_Zeros              : constant Boolean := True;
 175    Stack_Check_Default       : constant Boolean := False;
 176    Stack_Check_Probes        : constant Boolean := True;
 177    Stack_Check_Limits        : constant Boolean := False;
 178    Support_Aggregates        : constant Boolean := True;
 179    Support_Composite_Assign  : constant Boolean := True;
 180    Support_Composite_Compare : constant Boolean := True;
 181    Support_Long_Shifts       : constant Boolean := True;
 182    Always_Compatible_Rep     : constant Boolean := True;
 183    Suppress_Standard_Library : constant Boolean := True;
 184    Use_Ada_Main_Program_Name : constant Boolean := False;
 185    Frontend_Exceptions       : constant Boolean := False;
 186    ZCX_By_Default            : constant Boolean := True;
 187 
 188    --  Select the appropriate entry point, linker script, and libraries for a
 189    --  PikeOS partition.
 190 
 191    --  Traditionally the entry point of a native application is _p4_entry. For
 192    --  an APEX application, it is _begin.
 193 
 194    --  In order to use the same link options for both personalities, _begin is
 195    --  used for native as well.
 196 
 197    pragma Linker_Options
 198       ("-u_begin" & ASCII.NUL & "-e_begin" & ASCII.NUL &
 199        "-nostdlib" & ASCII.NUL &
 200        "-T../scripts/app-ld-script" & ASCII.NUL &
 201        "-lvm" & ASCII.NUL & "-lp4" & ASCII.NUL & "-lstand" & ASCII.NUL &
 202        "-lgcc");
 203 
 204 end System;