File : get_targ.ads
1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT COMPILER COMPONENTS --
4 -- --
5 -- G E T _ T A R G --
6 -- --
7 -- S p e c --
8 -- --
9 -- Copyright (C) 1992-2014, Free Software Foundation, Inc. --
10 -- --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
20 -- --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
23 -- --
24 ------------------------------------------------------------------------------
25
26 -- This package provides an Import to the C functions which provide
27 -- values related to types on the target system. It is only needed for
28 -- exp_dbug and the elaboration of ttypes, via the Set_Targs package.
29 -- It also contains the routine for registering floating-point types.
30
31 -- NOTE: Any changes in this package must be reflected in aa_getta.adb
32 -- and any other version in the various back ends.
33
34 -- Note that all these values return sizes of C types with corresponding
35 -- names. This allows GNAT to define the corresponding Ada types to have
36 -- the same representation. There is one exception to this general rule:
37 -- the Wide_Character_Type uses twice the size of a C char, instead of the
38 -- size of wchar_t.
39
40 with Einfo; use Einfo;
41 with Types; use Types;
42
43 package Get_Targ is
44
45 -- Functions returning individual runtime values
46
47 function Get_Bits_Per_Unit return Pos;
48 -- System.Storage_Unit
49
50 function Get_Bits_Per_Word return Pos;
51 -- System.Word_Size
52
53 function Get_Char_Size return Pos;
54 -- Size of Standard.Character
55
56 function Get_Wchar_T_Size return Pos;
57 -- Size of Interfaces.C.wchar_t
58
59 function Get_Short_Size return Pos;
60 -- Size of Standard.Short_Integer
61
62 function Get_Int_Size return Pos;
63 -- Size of Standard.Integer
64
65 function Get_Long_Size return Pos;
66 -- Size of Standard.Long_Integer
67
68 function Get_Long_Long_Size return Pos;
69 -- Size of Standard.Long_Long_Integer
70
71 function Get_Pointer_Size return Pos;
72 -- Size of System.Address
73
74 function Get_Maximum_Alignment return Pos;
75 -- Maximum supported alignment
76
77 function Get_Float_Words_BE return Nat;
78 -- Non-zero iff float words big endian
79
80 function Get_Words_BE return Nat;
81 -- Non-zero iff integer words big endian
82
83 function Get_Bytes_BE return Nat;
84 -- Non-zero iff bytes big-endian
85
86 function Get_Bits_BE return Nat;
87 -- Non-zero iff bit order big endian
88
89 function Get_Strict_Alignment return Nat;
90 -- Non-zero if target requires strict alignent
91
92 function Get_System_Allocator_Alignment return Nat;
93 -- Alignment guaranteed by malloc falls
94
95 function Get_Double_Float_Alignment return Nat;
96 -- Alignment required for Long_Float or 0 if no special requirement
97
98 function Get_Double_Scalar_Alignment return Nat;
99 -- Alignment required for Long_Long_Integer or larger integer types
100 -- or 0 if no special requirement.
101
102 function Get_Short_Enums return Int;
103 -- Returns non-zero if we are in short enums mode, where foreign convention
104 -- (in particular C and C++) enumeration types will be sized as in Ada,
105 -- using the shortest possibility from 8,16,32 bits, signed or unsigned.
106 -- A zero value means Short_Enums are not in use, and in this case all
107 -- foreign convention enumeration types are given the same size as c int.
108
109 -- Other subprograms
110
111 function Get_Max_Unaligned_Field return Pos;
112 -- Returns the maximum supported size in bits for a field that is
113 -- not aligned on a storage unit boundary.
114
115 function Width_From_Size (Size : Pos) return Pos;
116 function Digits_From_Size (Size : Pos) return Pos;
117 -- Calculate values for 'Width or 'Digits from 'Size
118
119 type C_String is array (0 .. 255) of aliased Character;
120 pragma Convention (C, C_String);
121
122 type Register_Type_Proc is access procedure
123 (C_Name : C_String; -- Nul-terminated string with name of type
124 Digs : Natural; -- Digits for floating point, 0 otherwise
125 Complex : Boolean; -- True iff type has real and imaginary parts
126 Count : Natural; -- Number of elements in vector, 0 otherwise
127 Float_Rep : Float_Rep_Kind; -- Representation used for fpt type
128 Precision : Positive; -- Precision of representation in bits
129 Size : Positive; -- Size of representation in bits
130 Alignment : Natural); -- Required alignment in bits
131 pragma Convention (C, Register_Type_Proc);
132 -- Call back procedure for Register_Back_End_Types. This is to be used by
133 -- Create_Standard to create predefined types for all types supported by
134 -- the back end.
135
136 procedure Register_Back_End_Types (Call_Back : Register_Type_Proc);
137 -- Calls the Call_Back function with information for each supported type
138
139 function Get_Back_End_Config_File return String_Ptr;
140 -- Return the back end configuration file, or null if none. If non-null,
141 -- this file should be used instead of calling the various Get_xxx
142 -- functions in this package.
143
144 end Get_Targ;