gcc/fixed-value.h

   1 /* Fixed-point arithmetic support.
   2    Copyright (C) 2006-2013 Free Software Foundation, Inc.
   3
   4 This file is part of GCC.
   5
   6 GCC is free software; you can redistribute it and/or modify it under
   7 the terms of the GNU General Public License as published by the Free
   8 Software Foundation; either version 3, or (at your option) any later
   9 version.
  10
  11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14 for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GCC; see the file COPYING3.  If not see
  18 <http://www.gnu.org/licenses/>.  */
  19
  20 #ifndef GCC_FIXED_VALUE_H
  21 #define GCC_FIXED_VALUE_H
  22
  23 #include "machmode.h"
  24 #include "real.h"
  25 #include "double-int.h"
  26
  27 struct GTY(()) fixed_value
  28 {
  29   double_int data;              /* Store data up to 2 wide integers.  */
  30   enum machine_mode mode;       /* Use machine mode to know IBIT and FBIT.  */
  31 };
  32
  33 #define FIXED_VALUE_TYPE struct fixed_value
  34
  35 #define MAX_FCONST0     18      /* For storing 18 fixed-point zeros per
  36                                    fract, ufract, accum, and uaccum modes .  */
  37 #define MAX_FCONST1     8       /* For storing 8 fixed-point ones per accum
  38                                    and uaccum modes.  */
  39 /* Constant fixed-point values 0 and 1.  */
  40 extern FIXED_VALUE_TYPE fconst0[MAX_FCONST0];
  41 extern FIXED_VALUE_TYPE fconst1[MAX_FCONST1];
  42
  43 /* Macros to access fconst0 and fconst1 via machine modes.  */
  44 #define FCONST0(mode)   fconst0[mode - QQmode]
  45 #define FCONST1(mode)   fconst1[mode - HAmode]
  46
  47 /* Return a CONST_FIXED with value R and mode M.  */
  48 #define CONST_FIXED_FROM_FIXED_VALUE(r, m) \
  49   const_fixed_from_fixed_value (r, m)
  50 extern rtx const_fixed_from_fixed_value (FIXED_VALUE_TYPE, enum machine_mode);
  51
  52 /* Construct a FIXED_VALUE from a bit payload and machine mode MODE.
  53    The bits in PAYLOAD are sign-extended/zero-extended according to MODE.  */
  54 extern FIXED_VALUE_TYPE fixed_from_double_int (double_int,
  55                                                      enum machine_mode);
  56
  57 /* Return a CONST_FIXED from a bit payload and machine mode MODE.
  58    The bits in PAYLOAD are sign-extended/zero-extended according to MODE.  */
  59 static inline rtx
  60 const_fixed_from_double_int (double_int payload,
  61                              enum machine_mode mode)
  62 {
  63   return
  64     const_fixed_from_fixed_value (fixed_from_double_int (payload, mode),
  65                                   mode);
  66 }
  67
  68 /* Initialize from a decimal or hexadecimal string.  */
  69 extern void fixed_from_string (FIXED_VALUE_TYPE *, const char *,
  70                                enum machine_mode);
  71
  72 /* In tree.c: wrap up a FIXED_VALUE_TYPE in a tree node.  */
  73 extern tree build_fixed (tree, FIXED_VALUE_TYPE);
  74
  75 /* Extend or truncate to a new mode.  */
  76 extern bool fixed_convert (FIXED_VALUE_TYPE *, enum machine_mode,
  77                            const FIXED_VALUE_TYPE *, bool);
  78
  79 /* Convert to a fixed-point mode from an integer.  */
  80 extern bool fixed_convert_from_int (FIXED_VALUE_TYPE *, enum machine_mode,
  81                                     double_int, bool, bool);
  82
  83 /* Convert to a fixed-point mode from a real.  */
  84 extern bool fixed_convert_from_real (FIXED_VALUE_TYPE *, enum machine_mode,
  85                                      const REAL_VALUE_TYPE *, bool);
  86
  87 /* Convert to a real mode from a fixed-point.  */
  88 extern void real_convert_from_fixed (REAL_VALUE_TYPE *, enum machine_mode,
  89                                      const FIXED_VALUE_TYPE *);
  90
  91 /* Compare two fixed-point objects for bitwise identity.  */
  92 extern bool fixed_identical (const FIXED_VALUE_TYPE *, const FIXED_VALUE_TYPE *);
  93
  94 /* Calculate a hash value.  */
  95 extern unsigned int fixed_hash (const FIXED_VALUE_TYPE *);
  96
  97 #define FIXED_VALUES_IDENTICAL(x, y)    fixed_identical (&(x), &(y))
  98
  99 /* Determine whether a fixed-point value X is negative.  */
 100 #define FIXED_VALUE_NEGATIVE(x)         fixed_isneg (&(x))
 101
 102 /* Render F as a decimal floating point constant.  */
 103 extern void fixed_to_decimal (char *str, const FIXED_VALUE_TYPE *, size_t);
 104
 105 /* Binary or unary arithmetic on tree_code.  */
 106 extern bool fixed_arithmetic (FIXED_VALUE_TYPE *, int, const FIXED_VALUE_TYPE *,
 107                               const FIXED_VALUE_TYPE *, bool);
 108
 109 /* Compare fixed-point values by tree_code.  */
 110 extern bool fixed_compare (int, const FIXED_VALUE_TYPE *,
 111                            const FIXED_VALUE_TYPE *);
 112
 113 /* Determine whether a fixed-point value X is negative.  */
 114 extern bool fixed_isneg (const FIXED_VALUE_TYPE *);
 115
 116 #endif /* GCC_FIXED_VALUE_H */