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
  26 /* bit manipulation routines:
  27
  28    Bit numbering: The bits are numbered according to the PowerPC
  29    convention - the left most (or most significant) is bit 0 while the
  30    right most (least significant) is bit 1.
  31
  32    Size convention: Each macro is in three forms - <MACRO>32 which
  33    operates in 32bit quantity (bits are numbered 0..31); <MACRO>64
  34    which operates using 64bit quantites (and bits are numbered 0..64);
  35    and <MACRO> which operates using the bit size of the target
  36    architecture (bits are still numbered 0..63), with 32bit
  37    architectures ignoring the first 32bits having bit 32 as the most
  38    significant.
  39
  40    BIT*(POS): Quantity with just 1 bit set.
  41
  42    MASK*(FIRST, LAST): Create a constant bit mask of the specified
  43    size with bits [FIRST .. LAST] set.
  44
  45    MASKED*(VALUE, FIRST, LAST): Masks out all but bits [FIRST
  46    .. LAST].
  47
  48    EXTRACTED*(VALUE, FIRST, LAST): Masks out bits [FIRST .. LAST] but
  49    also right shifts the masked value so that bit LAST becomes the
  50    least significant (right most).
  51
  52    SHUFFLED**(VALUE, OLD, NEW): Mask then move a single bit from OLD
  53    new NEW.
  54
  55    MOVED**(VALUE, OLD_FIRST, OLD_LAST, NEW_FIRST, NEW_LAST): Moves
  56    things around so that bits OLD_FIRST..OLD_LAST are masked then
  57    moved to NEW_FIRST..NEW_LAST.
  58
  59    INSERTED*(VALUE, FIRST, LAST): Takes VALUE and `inserts' the (LAST
  60    - FIRST + 1) least significant bits into bit positions [ FIRST
  61    .. LAST ].  This is almost the complement to EXTRACTED.
  62
  63    IEA_MASKED(SHOULD_MASK, ADDR): Convert the address to the targets
  64    natural size.  If in 32bit mode, discard the high 32bits.
  65
  66    EXTENDED(VALUE): Convert VALUE (32bits of it) to the targets
  67    natural size.  If in 64bit mode, sign extend the value.
  68
  69    ALIGN_*(VALUE): Round upwards the value so that it is aligned.
  70
  71    FLOOR_*(VALUE): Truncate the value so that it is aligned.
  72
  73    ROTL*(VALUE, NR_BITS): Return the value rotated by NR_BITS
  74
  75    */
  76
  77 #define _MAKE_SHIFT(WIDTH, pos) ((WIDTH) - 1 - (pos))
  78
  79
  80 /* MakeBit */
  81 #define _BITn(WIDTH, pos) (((natural##WIDTH)(1)) \
  82                            << _MAKE_SHIFT(WIDTH, pos))
  83
  84 #define BIT4(POS)  (1 << _MAKE_SHIFT(4, POS))
  85 #define BIT5(POS)  (1 << _MAKE_SHIFT(5, POS))
  86 #define BIT8(POS)  (1 << _MAKE_SHIFT(8, POS))
  87 #define BIT10(POS)  (1 << _MAKE_SHIFT(10, POS))
  88 #define BIT32(POS) _BITn(32, POS)
  89 #define BIT64(POS) _BITn(64, POS)
  90
  91 #if (WITH_TARGET_WORD_BITSIZE == 64)
  92 #define BIT(POS)   BIT64(POS)
  93 #else
  94 #define BIT(POS)   (((POS) < 32) ? 0 : _BITn(32, (POS)-32))
  95 #endif
  96
  97
  98 /* multi bit mask */
  99 #define _MASKn(WIDTH, START, STOP) \
 100 (((((unsigned##WIDTH)0) - 1) \
 101   >> (WIDTH - ((STOP) - (START) + 1))) \
 102  << (WIDTH - 1 - (STOP)))
 103
 104 #define MASK32(START, STOP)   _MASKn(32, START, STOP)
 105 #define MASK64(START, STOP)   _MASKn(64, START, STOP)
 106
 107 #if (WITH_TARGET_WORD_BITSIZE == 64)
 108 #define MASK(START, STOP) \
 109 (((START) <= (STOP)) \
 110  ? _MASKn(64, START, STOP) \
 111  : (_MASKn(64, 0, STOP) \
 112     | _MASKn(64, START, 63)))
 113 #else
 114 #define MASK(START, STOP) \
 115 (((START) <= (STOP)) \
 116  ? (((STOP) < 32) \
 117     ? 0 \
 118     : _MASKn(32, \
 119              (START) < 32 ? 0 : (START) - 32, \
 120              (STOP)-32)) \
 121  : (_MASKn(32, \
 122            (START) < 32 ? 0 : (START) - 32, \
 123            31) \
 124     | (((STOP) < 32) \
 125        ? 0 \
 126        : _MASKn(32, \
 127                 0, \
 128                 (STOP) - 32))))
 129 #endif
 130
 131
 132 /* mask the required bits, leaving them in place */
 133
 134 INLINE_BITS\
 135 (unsigned32) MASKED32
 136 (unsigned32 word,
 137  unsigned start,
 138  unsigned stop);
 139
 140 INLINE_BITS\
 141 (unsigned64) MASKED64
 142 (unsigned64 word,
 143  unsigned start,
 144  unsigned stop);
 145
 146 INLINE_BITS\
 147 (unsigned_word) MASKED
 148 (unsigned_word word,
 149  unsigned start,
 150  unsigned stop);
 151
 152
 153 /* extract the required bits aligning them with the lsb */
 154 #define _EXTRACTEDn(WIDTH, WORD, START, STOP) \
 155 ((((natural##WIDTH)(WORD)) >> (WIDTH - (STOP) - 1)) \
 156  & _MASKn(WIDTH, WIDTH-1+(START)-(STOP), WIDTH-1))
 157
 158 /* #define EXTRACTED10(WORD, START, STOP) _EXTRACTEDn(10, WORD, START, STOP) */
 159 #define EXTRACTED32(WORD, START, STOP) _EXTRACTEDn(32, WORD, START, STOP)
 160 #define EXTRACTED64(WORD, START, STOP) _EXTRACTEDn(64, WORD, START, STOP)
 161
 162 INLINE_BITS\
 163 (unsigned_word) EXTRACTED
 164 (unsigned_word val,
 165  unsigned start,
 166  unsigned stop);
 167
 168
 169 /* move a single bit around */
 170 /* NB: the wierdness (N>O?N-O:0) is to stop a warning from GCC */
 171 #define _SHUFFLEDn(N, WORD, OLD, NEW) \
 172 ((OLD) < (NEW) \
 173  ? (((unsigned##N)(WORD) \
 174      >> (((NEW) > (OLD)) ? ((NEW) - (OLD)) : 0)) \
 175     & MASK32((NEW), (NEW))) \
 176  : (((unsigned##N)(WORD) \
 177      << (((OLD) > (NEW)) ? ((OLD) - (NEW)) : 0)) \
 178     & MASK32((NEW), (NEW))))
 179
 180 #define SHUFFLED32(WORD, OLD, NEW) _SHUFFLEDn(32, WORD, OLD, NEW)
 181 #define SHUFFLED64(WORD, OLD, NEW) _SHUFFLEDn(64, WORD, OLD, NEW)
 182
 183 #define SHUFFLED(WORD, OLD, NEW) _SHUFFLEDn(_word, WORD, OLD, NEW)
 184
 185
 186 /* move a group of bits around */
 187 #define _INSERTEDn(N, WORD, START, STOP) \
 188 (((natural##N)(WORD) << _MAKE_SHIFT(N, STOP)) & _MASKn(N, START, STOP))
 189
 190 #define INSERTED32(WORD, START, STOP) _INSERTEDn(32, WORD, START, STOP)
 191 #define INSERTED64(WORD, START, STOP) _INSERTEDn(64, WORD, START, STOP)
 192
 193 INLINE_BITS\
 194 (unsigned_word) INSERTED
 195 (unsigned_word val,
 196  unsigned start,
 197  unsigned stop);
 198
 199
 200 /* depending on MODE return a 64bit or 32bit (sign extended) value */
 201 #if (WITH_TARGET_WORD_BITSIZE == 64)
 202 #define EXTENDED(X)     ((signed64)(signed32)(X))
 203 #else
 204 #define EXTENDED(X)     (X)
 205 #endif
 206
 207
 208 /* memory alignment macro's */
 209 #define _ALIGNa(A,X)  (((X) + ((A) - 1)) & ~((A) - 1))
 210 #define _FLOORa(A,X)  ((X) & ~((A) - 1))
 211
 212 #define ALIGN_8(X)      _ALIGNa(8, X)
 213 #define ALIGN_16(X)     _ALIGNa(16, X)
 214
 215 #define ALIGN_PAGE(X)   _ALIGNa(0x1000, X)
 216 #define FLOOR_PAGE(X)   ((X) & ~(0x1000 - 1))
 217
 218
 219 /* bit bliting macro's */
 220 #define BLIT32(V, POS, BIT) \
 221 do { \
 222   if (BIT) \
 223     V |= BIT32(POS); \
 224   else \
 225     V &= ~BIT32(POS); \
 226 } while (0)
 227 #define MBLIT32(V, LO, HI, VAL) \
 228 do { \
 229   (V) = (((V) & ~MASK32((LO), (HI))) \
 230          | INSERTED32(VAL, LO, HI)); \
 231 } while (0)
 232
 233
 234 /* some rotate functions to make things easier
 235
 236    NOTE: These are functions not macro's as the latter tickles bugs in
 237    gcc-2.6.3 */
 238
 239 #define _ROTLn(N, VAL, SHIFT) \
 240 (((VAL) << (SHIFT)) | ((VAL) >> ((N)-(SHIFT))))
 241
 242 INLINE_BITS\
 243 (unsigned32) ROTL32
 244 (unsigned32 val,
 245  long shift);
 246
 247 INLINE_BITS\
 248 (unsigned64) ROTL64
 249 (unsigned64 val,
 250  long shift);
 251
 252
 253 #if (BITS_INLINE & INCLUDE_MODULE)
 254 #include "bits.c"
 255 #endif
 256
 257 #endif /* _BITS_H_ */