sim/ppc/bits.h

   1 /*  This file is part of the program psim.
   2
   3     Copyright (C) 1994-1995, Andrew Cagney <cagney@highland.com.au>
   4
   5     This program is free software; you can redistribute it and/or modify
   6     it under the terms of the GNU General Public License as published by
   7     the Free Software Foundation; either version 2 of the License, or
   8     (at your option) any later version.
   9
  10     This program is distributed in the hope that it will be useful,
  11     but WITHOUT ANY WARRANTY; without even the implied warranty of
  12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13     GNU General Public License for more details.
  14
  15     You should have received a copy of the GNU General Public License
  16     along with this program; if not, write to the Free Software
  17     Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  18
  19     */
  20
  21
  22 #ifndef _BITS_H_
  23 #define _BITS_H_
  24
  25 /* bit manipulation routines:
  26
  27    Bit numbering: The bits are numbered according to the PowerPC
  28    convention - the left most (or most significant) is bit 0 while the
  29    right most (least significant) is bit 1.
  30
  31    Size convention: Each macro is in three forms - <MACRO>32 which
  32    operates in 32bit quantity (bits are numbered 0..31); <MACRO>64
  33    which operates using 64bit quantites (and bits are numbered 0..64);
  34    and <MACRO> which operates using the bit size of the target
  35    architecture (bits are still numbered 0..63), with 32bit
  36    architectures ignoring the first 32bits having bit 32 as the most
  37    significant.
  38
  39    BIT*(POS): Quantity with just 1 bit set.
  40
  41    MASK*(FIRST, LAST): Create a constant bit mask of the specified
  42    size with bits [FIRST .. LAST] set.
  43
  44    MASKED*(VALUE, FIRST, LAST): Masks out all but bits [FIRST
  45    .. LAST].
  46
  47    EXTRACTED*(VALUE, FIRST, LAST): Masks out bits [FIRST .. LAST] but
  48    also right shifts the masked value so that bit LAST becomes the
  49    least significant (right most).
  50
  51    SHUFFLE*(VALUE, OLD, NEW): Moves things around so that bit pos OLD
  52    is extracted and than moved to bit pos NEW.
  53
  54
  55
  56    IEA_MASKED(SHOULD_MASK, ADDR): Convert the address to the targets
  57    natural size.  If in 32bit mode, discard the high 32bits.
  58
  59    EXTENDED(VALUE): Convert VALUE (32bits of it) to the targets
  60    natural size.  If in 64bit mode, sign extend the value.
  61
  62    */
  63
  64 /* Bit operators */
  65 #define BIT4(POS)  (1 << _MAKE_SHIFT(4, POS))
  66 #define BIT5(POS)  (1 << _MAKE_SHIFT(5, POS))
  67 #define BIT10(POS)  (1 << _MAKE_SHIFT(10, POS))
  68 #define BIT32(POS) _BITn(32, POS)
  69 #define BIT64(POS) _BITn(64, POS)
  70
  71 #if (WITH_64BIT_TARGET)
  72 #define BIT(POS)   BIT64(POS)
  73 #else
  74 #define BIT(POS)   (((POS) < 32) ? 0 : _BITn(32, (POS)-32))
  75 #endif
  76
  77
  78 /* multi bit mask */
  79
  80 #define MASK32(START, STOP)   _MASKn(32, START, STOP)
  81 #define MASK64(START, STOP)   _MASKn(64, START, STOP)
  82
  83 #if (WITH_64BIT_TARGET)
  84 #define MASK(START, STOP) (((START) <= (STOP)) \
  85                            ? _MASKn(64, START, STOP) \
  86                            : (_MASKn(64, 0, STOP) \
  87                               | _MASKn(64, START, 63)))
  88 #else
  89 #define MASK(START, STOP)  (((START) <= (STOP)) \
  90                             ? (((STOP) < 32) \
  91                                ? 0 \
  92                                : _MASKn(32, \
  93                                         (START) < 32 ? 0 : (START) - 32, \
  94                                         (STOP)-32)) \
  95                             : (_MASKn(32, \
  96                                       (START) < 32 ? 0 : (START) - 32, \
  97                                       31) \
  98                                | (((STOP) < 32) \
  99                                   ? 0 \
 100                                   : _MASKn(32, \
 101                                            0, \
 102                                            (STOP) - 32))))
 103 #endif
 104
 105
 106 #define MASKED32(WORD, START, STOP)    _MASKEDn(32, WORD, START, STOP)
 107 #define MASKED64(WORD, START, STOP)    _MASKEDn(64, WORD, START, STOP)
 108 #define MASKED10(WORD, START, STOP)    _MASKEDn(10, WORD, START, STOP)
 109 #define EXTRACTED32(WORD, START, STOP) _EXTRACTEDn(32, WORD, START, STOP)
 110 #define EXTRACTED64(WORD, START, STOP) _EXTRACTEDn(64, WORD, START, STOP)
 111 #define EXTRACTED10(WORD, START, STOP) _EXTRACTEDn(10, WORD, START, STOP)
 112
 113 #define MASKED(WORD, START, STOP)   ((natural_word)(WORD) & MASK(START, STOP))
 114 #if (WITH_64BITS_TARGET)
 115 #define EXTRACTED(WORD, START, STOP)   _EXTRACTEDn(64, WORD, START, STOP)
 116 #else
 117 #define EXTRACTED(WORD, START, STOP) (STOP < 32 \
 118                                       ? 0 \
 119                                       : (((natural_word)WORD \
 120                                           >> (63 - (STOP))) \
 121                                          && MASK(START+(63-STOP), 63)))
 122 #endif
 123
 124
 125 #define SHUFFLE32(WORD, OLD, NEW) _SHUFFLEn(32, WORD, OLD, NEW)
 126 #define SHUFFLE64(WORD, OLD, NEW) _SHUFFLEn(64, WORD, OLD, NEW)
 127 #define SHUFFLE(WORD, OLD, NEW) _SHUFFLEn(_word, WORD, OLD, NEW)
 128 /* NB: the wierdness (N>O?N-O:0) is to stop a warning from GCC */
 129 #define _SHUFFLEn(N, WORD, OLD, NEW) \
 130 ((OLD) < (NEW) \
 131  ? (((unsigned##N)(WORD) \
 132      >> (((NEW) > (OLD)) ? ((NEW) - (OLD)) : 0)) \
 133     & MASK32((NEW), (NEW))) \
 134  : (((unsigned##N)(WORD) \
 135      << (((OLD) > (NEW)) ? ((OLD) - (NEW)) : 0)) \
 136     & MASK32((NEW), (NEW))))
 137
 138
 139
 140 /* depending on MODE return a 64bit or 32bit (sign extended) value */
 141 #if (WITH_64BIT_TARGET)
 142 #define EXTENDED(X)     ((signed64)(signed32)(X))
 143 #else
 144 #define EXTENDED(X)     (X)
 145 #endif
 146
 147
 148
 149
 150 /* memory alignment macro's */
 151 #define _ALIGNa(A,X)  (((X) + ((A)-1)) & ~((A)-1))
 152 #define ALIGN_8(X)      _ALIGNa(8, X)
 153 #define ALIGN_16(X)     _ALIGNa(16, X)
 154 #define ALIGN_PAGE(X)   _ALIGNa(0x1000, X)
 155 #define FLOOR_PAGE(X)   ((X) & ~(0x1000 - 1))
 156
 157 /* bit bliting macro's */
 158 #define BLIT32(V, POS, BIT) \
 159 do { \
 160   if (BIT) \
 161     V |= BIT32(POS); \
 162   else \
 163     V &= ~BIT32(POS); \
 164 } while (0)
 165 #define MLIT32(V, LO, HI, VAL) \
 166 do { \
 167   (V) = (((V) & ~MASK32((LO), (HI))) \
 168          | ((VAL) << _MAKE_SHIFT(32,HI))); \
 169 } while (0)
 170
 171
 172
 173 /* Things for creating single bit set values */
 174 /* MakeBit */
 175 #define _MAKE_SHIFT(WIDTH, pos) (WIDTH - 1 - (pos))
 176 #define _BITn(WIDTH, pos) (((natural##WIDTH)(1)) \
 177                            << _MAKE_SHIFT(WIDTH, pos))
 178 /* MakeBitMask */
 179 #define _MASKn(WIDTH, START, STOP) (((((unsigned##WIDTH)0) - 1) \
 180                                      >> (WIDTH - ((STOP) - (START) + 1))) \
 181                                     << (WIDTH - 1 - (STOP)))
 182
 183
 184
 185 /* mask the required bits, leaving them in place */
 186 #define _MASKEDn(WIDTH, WORD, START, STOP) \
 187 (((natural##WIDTH)(WORD)) & MASK##WIDTH(START, STOP))
 188
 189 /* extract the required bits aligning them with the lsb */
 190 #define _EXTRACTEDn(WIDTH, WORD, START, STOP) \
 191 ((((natural##WIDTH)(WORD)) >> (WIDTH - (STOP) - 1)) \
 192  & _MASKn(WIDTH, WIDTH-1+(START)-(STOP), WIDTH-1))
 193
 194 #endif /* _BITS_H_ */