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 3 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, see <http://www.gnu.org/licenses/>.
  17
  18     */
  19
  20
  21 #ifndef _BITS_H_
  22 #define _BITS_H_
  23
  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    LSMASKED*(VALUE, FIRST, LAST): Like MASKED - LS bit is zero.
  48
  49    EXTRACTED*(VALUE, FIRST, LAST): Masks out bits [FIRST .. LAST] but
  50    also right shifts the masked value so that bit LAST becomes the
  51    least significant (right most).
  52
  53    LSEXTRACTED*(VALUE, FIRST, LAST): Same as extracted - LS bit is
  54    zero.
  55
  56    SHUFFLED**(VALUE, OLD, NEW): Mask then move a single bit from OLD
  57    new NEW.
  58
  59    MOVED**(VALUE, OLD_FIRST, OLD_LAST, NEW_FIRST, NEW_LAST): Moves
  60    things around so that bits OLD_FIRST..OLD_LAST are masked then
  61    moved to NEW_FIRST..NEW_LAST.
  62
  63    INSERTED*(VALUE, FIRST, LAST): Takes VALUE and `inserts' the (LAST
  64    - FIRST + 1) least significant bits into bit positions [ FIRST
  65    .. LAST ].  This is almost the complement to EXTRACTED.
  66
  67    IEA_MASKED(SHOULD_MASK, ADDR): Convert the address to the targets
  68    natural size.  If in 32bit mode, discard the high 32bits.
  69
  70    EXTENDED(VALUE): Convert VALUE (32bits of it) to the targets
  71    natural size.  If in 64bit mode, sign extend the value.
  72
  73    ALIGN_*(VALUE): Round upwards the value so that it is aligned.
  74
  75    FLOOR_*(VALUE): Truncate the value so that it is aligned.
  76
  77    ROTL*(VALUE, NR_BITS): Return the value rotated by NR_BITS
  78
  79    */
  80
  81 #define _MAKE_SHIFT(WIDTH, pos) ((WIDTH) - 1 - (pos))
  82
  83
  84 #if (WITH_TARGET_WORD_MSB == 0)
  85 #define _LSB_POS(WIDTH, SHIFT) (WIDTH - 1 - SHIFT)
  86 #else
  87 #define _LSB_POS(WIDTH, SHIFT) (SHIFT)
  88 #endif
  89
  90
  91 /* MakeBit */
  92 #define _BITn(WIDTH, pos) (((natural##WIDTH)(1)) \
  93                            << _MAKE_SHIFT(WIDTH, pos))
  94
  95 #define BIT4(POS)  (1 << _MAKE_SHIFT(4, POS))
  96 #define BIT5(POS)  (1 << _MAKE_SHIFT(5, POS))
  97 #define BIT8(POS)  (1 << _MAKE_SHIFT(8, POS))
  98 #define BIT10(POS)  (1 << _MAKE_SHIFT(10, POS))
  99 #define BIT32(POS) _BITn(32, POS)
 100 #define BIT64(POS) _BITn(64, POS)
 101
 102 #if (WITH_TARGET_WORD_BITSIZE == 64)
 103 #define BIT(POS)   BIT64(POS)
 104 #else
 105 #define BIT(POS)   (((POS) < 32) ? 0 : _BITn(32, (POS)-32))
 106 #endif
 107
 108
 109 /* multi bit mask */
 110 #define _MASKn(WIDTH, START, STOP) \
 111 (((((unsigned##WIDTH)0) - 1) \
 112   >> (WIDTH - ((STOP) - (START) + 1))) \
 113  << (WIDTH - 1 - (STOP)))
 114
 115 #define MASK32(START, STOP)   _MASKn(32, START, STOP)
 116 #define MASK64(START, STOP)   _MASKn(64, START, STOP)
 117
 118 /* Multi-bit mask on least significant bits */
 119
 120 #define _LSMASKn(WIDTH, FIRST, LAST) _MASKn (WIDTH, \
 121                                              _LSB_POS (WIDTH, FIRST), \
 122                                              _LSB_POS (WIDTH, LAST))
 123
 124 #define LSMASK64(FIRST, LAST)  _LSMASKn (64, (FIRST), (LAST))
 125
 126 #if (WITH_TARGET_WORD_BITSIZE == 64)
 127 #define MASK(START, STOP) \
 128 (((START) <= (STOP)) \
 129  ? _MASKn(64, START, STOP) \
 130  : (_MASKn(64, 0, STOP) \
 131     | _MASKn(64, START, 63)))
 132 #else
 133 #define MASK(START, STOP) \
 134 (((START) <= (STOP)) \
 135  ? (((STOP) < 32) \
 136     ? 0 \
 137     : _MASKn(32, \
 138              (START) < 32 ? 0 : (START) - 32, \
 139              (STOP)-32)) \
 140  : (_MASKn(32, \
 141            (START) < 32 ? 0 : (START) - 32, \
 142            31) \
 143     | (((STOP) < 32) \
 144        ? 0 \
 145        : _MASKn(32, \
 146                 0, \
 147                 (STOP) - 32))))
 148 #endif
 149
 150
 151 /* mask the required bits, leaving them in place */
 152
 153 INLINE_BITS\
 154 (unsigned32) MASKED32
 155 (unsigned32 word,
 156  unsigned start,
 157  unsigned stop);
 158
 159 INLINE_BITS\
 160 (unsigned64) MASKED64
 161 (unsigned64 word,
 162  unsigned start,
 163  unsigned stop);
 164
 165 INLINE_BITS\
 166 (unsigned_word) MASKED
 167 (unsigned_word word,
 168  unsigned start,
 169  unsigned stop);
 170
 171 INLINE_BITS\
 172 (unsigned64) LSMASKED64
 173 (unsigned64 word,
 174  int first,
 175   int last);
 176
 177
 178 /* extract the required bits aligning them with the lsb */
 179 #define _EXTRACTEDn(WIDTH, WORD, START, STOP) \
 180 ((((natural##WIDTH)(WORD)) >> (WIDTH - (STOP) - 1)) \
 181  & _MASKn(WIDTH, WIDTH-1+(START)-(STOP), WIDTH-1))
 182
 183 /* #define EXTRACTED10(WORD, START, STOP) _EXTRACTEDn(10, WORD, START, STOP) */
 184 #define EXTRACTED32(WORD, START, STOP) _EXTRACTEDn(32, WORD, START, STOP)
 185 #define EXTRACTED64(WORD, START, STOP) _EXTRACTEDn(64, WORD, START, STOP)
 186
 187 INLINE_BITS\
 188 (unsigned_word) EXTRACTED
 189 (unsigned_word val,
 190  unsigned start,
 191  unsigned stop);
 192
 193 INLINE_BITS\
 194 (unsigned64) LSEXTRACTED64
 195 (unsigned64 val,
 196  int start,
 197  int stop);
 198
 199 /* move a single bit around */
 200 /* NB: the wierdness (N>O?N-O:0) is to stop a warning from GCC */
 201 #define _SHUFFLEDn(N, WORD, OLD, NEW) \
 202 ((OLD) < (NEW) \
 203  ? (((unsigned##N)(WORD) \
 204      >> (((NEW) > (OLD)) ? ((NEW) - (OLD)) : 0)) \
 205     & MASK32((NEW), (NEW))) \
 206  : (((unsigned##N)(WORD) \
 207      << (((OLD) > (NEW)) ? ((OLD) - (NEW)) : 0)) \
 208     & MASK32((NEW), (NEW))))
 209
 210 #define SHUFFLED32(WORD, OLD, NEW) _SHUFFLEDn(32, WORD, OLD, NEW)
 211 #define SHUFFLED64(WORD, OLD, NEW) _SHUFFLEDn(64, WORD, OLD, NEW)
 212
 213 #define SHUFFLED(WORD, OLD, NEW) _SHUFFLEDn(_word, WORD, OLD, NEW)
 214
 215
 216 /* move a group of bits around */
 217 #define _INSERTEDn(N, WORD, START, STOP) \
 218 (((natural##N)(WORD) << _MAKE_SHIFT(N, STOP)) & _MASKn(N, START, STOP))
 219
 220 #define INSERTED32(WORD, START, STOP) _INSERTEDn(32, WORD, START, STOP)
 221 #define INSERTED64(WORD, START, STOP) _INSERTEDn(64, WORD, START, STOP)
 222
 223 INLINE_BITS\
 224 (unsigned_word) INSERTED
 225 (unsigned_word val,
 226  unsigned start,
 227  unsigned stop);
 228
 229
 230 /* depending on MODE return a 64bit or 32bit (sign extended) value */
 231 #if (WITH_TARGET_WORD_BITSIZE == 64)
 232 #define EXTENDED(X)     ((signed64)(signed32)(X))
 233 #else
 234 #define EXTENDED(X)     (X)
 235 #endif
 236
 237
 238 /* memory alignment macro's */
 239 #define _ALIGNa(A,X)  (((X) + ((A) - 1)) & ~((A) - 1))
 240 #define _FLOORa(A,X)  ((X) & ~((A) - 1))
 241
 242 #define ALIGN_8(X)      _ALIGNa(8, X)
 243 #define ALIGN_16(X)     _ALIGNa(16, X)
 244
 245 #define ALIGN_PAGE(X)   _ALIGNa(0x1000, X)
 246 #define FLOOR_PAGE(X)   ((X) & ~(0x1000 - 1))
 247
 248
 249 /* bit bliting macro's */
 250 #define BLIT32(V, POS, BIT) \
 251 do { \
 252   if (BIT) \
 253     V |= BIT32(POS); \
 254   else \
 255     V &= ~BIT32(POS); \
 256 } while (0)
 257 #define MBLIT32(V, LO, HI, VAL) \
 258 do { \
 259   (V) = (((V) & ~MASK32((LO), (HI))) \
 260          | INSERTED32(VAL, LO, HI)); \
 261 } while (0)
 262
 263
 264 /* some rotate functions to make things easier
 265
 266    NOTE: These are functions not macro's as the latter tickles bugs in
 267    gcc-2.6.3 */
 268
 269 #define _ROTLn(N, VAL, SHIFT) \
 270 (((VAL) << (SHIFT)) | ((VAL) >> ((N)-(SHIFT))))
 271
 272 INLINE_BITS\
 273 (unsigned32) ROTL32
 274 (unsigned32 val,
 275  long shift);
 276
 277 INLINE_BITS\
 278 (unsigned64) ROTL64
 279 (unsigned64 val,
 280  long shift);
 281
 282
 283 #if (BITS_INLINE & INCLUDE_MODULE)
 284 #include "bits.c"
 285 #endif
 286
 287 #endif /* _BITS_H_ */