OpenCores
URL https://opencores.org/ocsvn/openrisc/openrisc/trunk

Subversion Repositories openrisc

[/] [openrisc/] [trunk/] [gnu-dev/] [or1k-gcc/] [gcc/] [ada/] [s-fatgen.ads] - Blame information for rev 706

Details | Compare with Previous | View Log

Line No. Rev Author Line
1 706 jeremybenn
------------------------------------------------------------------------------
2
--                                                                          --
3
--                         GNAT COMPILER COMPONENTS                         --
4
--                                                                          --
5
--                       S Y S T E M . F A T _ G E N                        --
6
--                                                                          --
7
--                                 S p e c                                  --
8
--                                                                          --
9
--          Copyright (C) 1992-2009 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.                                     --
17
--                                                                          --
18
-- As a special exception under Section 7 of GPL version 3, you are granted --
19
-- additional permissions described in the GCC Runtime Library Exception,   --
20
-- version 3.1, as published by the Free Software Foundation.               --
21
--                                                                          --
22
-- You should have received a copy of the GNU General Public License and    --
23
-- a copy of the GCC Runtime Library Exception along with this program;     --
24
-- see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see    --
25
-- <http://www.gnu.org/licenses/>.                                          --
26
--                                                                          --
27
-- GNAT was originally developed  by the GNAT team at  New York University. --
28
-- Extensive contributions were provided by Ada Core Technologies Inc.      --
29
--                                                                          --
30
------------------------------------------------------------------------------
31
 
32
--  This generic package provides a target independent implementation of the
33
--  floating-point attributes that denote functions. The implementations here
34
--  are portable, but very slow. The runtime contains a set of instantiations
35
--  of this package for all predefined floating-point types, and these should
36
--  be replaced by efficient assembly language code where possible.
37
 
38
generic
39
    type T is digits <>;
40
 
41
package System.Fat_Gen is
42
   pragma Pure;
43
 
44
   subtype UI is Integer;
45
   --  The runtime representation of universal integer for the purposes of
46
   --  this package is integer. The expander generates conversions for the
47
   --  actual type used. For functions returning universal integer, there
48
   --  is no problem, since the result always is in range of integer. For
49
   --  input arguments, the expander has to do some special casing to deal
50
   --  with the (very annoying!) cases of out of range values. If we used
51
   --  Long_Long_Integer to represent universal, then there would be no
52
   --  problem, but the resulting inefficiency would be annoying.
53
 
54
   function Adjacent          (X, Towards : T)              return T;
55
 
56
   function Ceiling           (X : T)                       return T;
57
 
58
   function Compose           (Fraction : T; Exponent : UI) return T;
59
 
60
   function Copy_Sign         (Value, Sign : T)             return T;
61
 
62
   function Exponent          (X : T)                       return UI;
63
 
64
   function Floor             (X : T)                       return T;
65
 
66
   function Fraction          (X : T)                       return T;
67
 
68
   function Leading_Part      (X : T; Radix_Digits : UI)    return T;
69
 
70
   function Machine           (X : T)                       return T;
71
 
72
   function Machine_Rounding  (X : T)                       return T;
73
 
74
   function Model             (X : T)                       return T;
75
 
76
   function Pred              (X : T)                       return T;
77
 
78
   function Remainder         (X, Y : T)                    return T;
79
 
80
   function Rounding          (X : T)                       return T;
81
 
82
   function Scaling           (X : T; Adjustment : UI)      return T;
83
 
84
   function Succ              (X : T)                       return T;
85
 
86
   function Truncation        (X : T)                       return T;
87
 
88
   function Unbiased_Rounding (X : T)                       return T;
89
 
90
   function Valid (X : not null access T) return Boolean;
91
   --  This function checks if the object of type T referenced by X
92
   --  is valid, and returns True/False accordingly. The parameter is
93
   --  passed by reference (access) here, as the object of type T may
94
   --  be an abnormal value that cannot be passed in a floating-point
95
   --  register, and the whole point of 'Valid is to prevent exceptions.
96
   --  Note that the object of type T must have the natural alignment
97
   --  for type T. See Unaligned_Valid for further discussion.
98
   --
99
   --  Note: this routine does not work for Vax_Float ???
100
 
101
   function Unaligned_Valid (A : System.Address) return Boolean;
102
   --  This version of Valid is used if the floating-point value to
103
   --  be checked is not known to be aligned (for example it appears
104
   --  in a packed record). In this case, we cannot call Valid since
105
   --  Valid assumes proper full alignment. Instead Unaligned_Valid
106
   --  performs the same processing for a possibly unaligned float,
107
   --  by first doing a copy and then calling Valid. One might think
108
   --  that the front end could simply do a copy to an aligned temp,
109
   --  but remember that we may have an abnormal value that cannot
110
   --  be copied into a floating-point register, so things are a bit
111
   --  trickier than one might expect.
112
   --
113
   --  Note: Unaligned_Valid is never called for a target which does
114
   --  not require strict alignment (e.g. the ia32/x86), since on a
115
   --  target not requiring strict alignment, it is fine to pass a
116
   --  non-aligned value to the standard Valid routine.
117
   --
118
   --  Note: this routine does not work for Vax_Float ???
119
 
120
private
121
   pragma Inline (Machine);
122
   pragma Inline (Model);
123
 
124
   --  Note: previously the validity checking subprograms (Unaligned_Valid and
125
   --  Valid) were also inlined, but this was changed since there were some
126
   --  problems with this inlining in optimized mode, and in any case it seems
127
   --  better to avoid this inlining (space and robustness considerations).
128
 
129
end System.Fat_Gen;

powered by: WebSVN 2.1.0

© copyright 1999-2024 OpenCores.org, equivalent to Oliscience, all rights reserved. OpenCores®, registered trademark.