sreal.h revision 1.1.1.1.4.2 
1/* Definitions for simple data type for positive real numbers.
2   Copyright (C) 2002, 2003, 2007 Free Software Foundation, Inc.
3
4This file is part of GCC.
5
6GCC is free software; you can redistribute it and/or modify it under
7the terms of the GNU General Public License as published by the Free
8Software Foundation; either version 3, or (at your option) any later
9version.
10
11GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12WARRANTY; without even the implied warranty of MERCHANTABILITY or
13FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14for more details.
15
16You should have received a copy of the GNU General Public License
17along with GCC; see the file COPYING3.  If not see
18<http://www.gnu.org/licenses/>.  */
19
20#ifndef GCC_SREAL_H
21#define GCC_SREAL_H
22
23/* SREAL_PART_BITS has to be an even number.  */
24#if (HOST_BITS_PER_WIDE_INT / 2) % 2 == 1
25#define SREAL_PART_BITS (HOST_BITS_PER_WIDE_INT / 2 - 1)
26#else
27#define SREAL_PART_BITS (HOST_BITS_PER_WIDE_INT / 2)
28#endif
29
30#define uhwi unsigned HOST_WIDE_INT
31#define MAX_HOST_WIDE_INT (((uhwi) 1 << (HOST_BITS_PER_WIDE_INT - 1)) - 1)
32
33#define SREAL_MIN_SIG ((uhwi) 1 << (SREAL_PART_BITS - 1))
34#define SREAL_MAX_SIG (((uhwi) 1 << SREAL_PART_BITS) - 1)
35#define SREAL_MAX_EXP (INT_MAX / 4)
36
37#if SREAL_PART_BITS < 32
38#define SREAL_BITS (SREAL_PART_BITS * 2)
39#else
40#define SREAL_BITS SREAL_PART_BITS
41#endif
42
43/* Structure for holding a simple real number.  */
44typedef struct sreal
45{
46#if SREAL_PART_BITS < 32
47  unsigned HOST_WIDE_INT sig_lo;	/* Significant (lower part).  */
48  unsigned HOST_WIDE_INT sig_hi;	/* Significant (higher part).  */
49#else
50  unsigned HOST_WIDE_INT sig;		/* Significant.  */
51#endif
52  signed int exp;			/* Exponent.  */
53} sreal;
54
55extern void dump_sreal (FILE *, sreal *);
56extern sreal *sreal_init (sreal *, unsigned HOST_WIDE_INT, signed int);
57extern HOST_WIDE_INT sreal_to_int (sreal *);
58extern int sreal_compare (sreal *, sreal *);
59extern sreal *sreal_add (sreal *, sreal *, sreal *);
60extern sreal *sreal_sub (sreal *, sreal *, sreal *);
61extern sreal *sreal_mul (sreal *, sreal *, sreal *);
62extern sreal *sreal_div (sreal *, sreal *, sreal *);
63
64#endif
65