libhsail-rt/rt/bitstring.c

   1 /* bitstring.c -- Builtins for HSAIL bitstring instructions.
   2
   3    Copyright (C) 2015-2017 Free Software Foundation, Inc.
   4    Contributed by Pekka Jaaskelainen <pekka.jaaskelainen@parmance.com>
   5    for General Processor Tech.
   6
   7    Permission is hereby granted, free of charge, to any person obtaining a
   8    copy of this software and associated documentation files
   9    (the "Software"), to deal in the Software without restriction, including
  10    without limitation the rights to use, copy, modify, merge, publish,
  11    distribute, sublicense, and/or sell copies of the Software, and to
  12    permit persons to whom the Software is furnished to do so, subject to
  13    the following conditions:
  14
  15    The above copyright notice and this permission notice shall be included
  16    in all copies or substantial portions of the Software.
  17
  18    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  19    OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  20    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
  21    IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
  22    DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
  23    OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
  24    USE OR OTHER DEALINGS IN THE SOFTWARE.
  25 */
  26
  27 #include <stdint.h>
  28 #include <limits.h>
  29
  30 #define BITEXTRACT(DEST_TYPE, SRC0, SRC1, SRC2)                         \
  31   uint32_t offset = SRC1 & (sizeof (DEST_TYPE) * 8 - 1);                \
  32   uint32_t width = SRC2 & (sizeof (DEST_TYPE) * 8 - 1);                 \
  33   if (width == 0)                                                       \
  34     return 0;                                                           \
  35   else                                                                  \
  36     return (SRC0 << (sizeof (DEST_TYPE) * 8 - width - offset))          \
  37       >> (sizeof (DEST_TYPE) * 8 - width)
  38
  39 uint32_t
  40 __hsail_bitextract_u32 (uint32_t src0, uint32_t src1, uint32_t src2)
  41 {
  42   BITEXTRACT (uint32_t, src0, src1, src2);
  43 }
  44
  45 int32_t
  46 __hsail_bitextract_s32 (int32_t src0, uint32_t src1, uint32_t src2)
  47 {
  48   BITEXTRACT (int32_t, src0, src1, src2);
  49 }
  50
  51 uint64_t
  52 __hsail_bitextract_u64 (uint64_t src0, uint32_t src1, uint32_t src2)
  53 {
  54   BITEXTRACT (uint64_t, src0, src1, src2);
  55 }
  56
  57 int64_t
  58 __hsail_bitextract_s64 (int64_t src0, uint32_t src1, uint32_t src2)
  59 {
  60   BITEXTRACT (int64_t, src0, src1, src2);
  61 }
  62
  63 #define BITINSERT(DEST_TYPE, SRC0, SRC1, SRC2, SRC3)                    \
  64   uint32_t offset = SRC2 & (sizeof (DEST_TYPE) * 8 - 1);                \
  65   uint32_t width = SRC3 & (sizeof (DEST_TYPE) * 8 - 1);                 \
  66   DEST_TYPE mask = ((DEST_TYPE) 1 << width) - 1;                        \
  67   return (SRC0 & ~(mask << offset)) | ((SRC1 & mask) << offset)
  68
  69 uint32_t
  70 __hsail_bitinsert_u32 (uint32_t src0, uint32_t src1, uint32_t src2,
  71                               uint32_t src3)
  72 {
  73   BITINSERT (uint32_t, src0, src1, src2, src3);
  74 }
  75
  76 int64_t
  77 __hsail_bitinsert_u64 (uint64_t src0, uint64_t src1, uint32_t src2,
  78                               uint32_t src3)
  79 {
  80   BITINSERT (uint64_t, src0, src1, src2, src3);
  81 }
  82
  83 #define BITMASK(DEST_TYPE, SRC0, SRC1)                                  \
  84   uint32_t offset = SRC0 & (sizeof (DEST_TYPE) * 8 - 1);                \
  85   uint32_t width = SRC1 & (sizeof (DEST_TYPE) * 8 - 1);                 \
  86   DEST_TYPE mask = ((DEST_TYPE) 1 << width) - 1;                        \
  87   return mask << offset
  88
  89 uint32_t
  90 __hsail_bitmask_u32 (uint32_t src0, uint32_t src1)
  91 {
  92   BITMASK (uint32_t, src0, src1);
  93 }
  94
  95 uint64_t
  96 __hsail_bitmask_u64 (uint32_t src0, uint32_t src1)
  97 {
  98   BITMASK (uint64_t, src0, src1);
  99 }
 100
 101 /* The dummy, but readable version from
 102    http://graphics.stanford.edu/~seander/bithacks.html#BitReverseObvious
 103    This (also) often maps to a single instruction in DSPs.  */
 104
 105 #define BITREV(DEST_TYPE, SRC)                                          \
 106   DEST_TYPE v = SRC;                                                    \
 107   DEST_TYPE r = v;                                                      \
 108   int s = sizeof (SRC) * CHAR_BIT - 1;                                  \
 109                                                                         \
 110   for (v >>= 1; v; v >>= 1)                                             \
 111     {                                                                   \
 112       r <<= 1;                                                          \
 113       r |= v & 1;                                                       \
 114       s--;                                                              \
 115     }                                                                   \
 116   return r << s
 117
 118 uint32_t
 119 __hsail_bitrev_u32 (uint32_t src0)
 120 {
 121   BITREV (uint32_t, src0);
 122 }
 123
 124 uint64_t
 125 __hsail_bitrev_u64 (uint64_t src0)
 126 {
 127   BITREV (uint64_t, src0);
 128 }
 129
 130 uint32_t
 131 __hsail_bitselect_u32 (uint32_t src0, uint32_t src1, uint32_t src2)
 132 {
 133   return (src1 & src0) | (src2 & ~src0);
 134 }
 135
 136 uint64_t
 137 __hsail_bitselect_u64 (uint64_t src0, uint64_t src1, uint64_t src2)
 138 {
 139   return (src1 & src0) | (src2 & ~src0);
 140 }
 141
 142 /* Due to the defined behavior with 0, we cannot use the gcc builtin
 143    __builtin_clz* () directly. __builtin_ffs () has defined behavior, but
 144    returns 0 while HSAIL requires to return -1.  */
 145
 146 uint32_t
 147 __hsail_firstbit_u32 (uint32_t src0)
 148 {
 149   if (src0 == 0)
 150     return -1;
 151   return __builtin_clz (src0);
 152 }
 153
 154 uint32_t
 155 __hsail_firstbit_s32 (int32_t src0)
 156 {
 157   uint32_t converted = src0 >= 0 ? src0 : ~src0;
 158   return __hsail_firstbit_u32 (converted);
 159 }
 160
 161 uint32_t
 162 __hsail_firstbit_u64 (uint64_t src0)
 163 {
 164   if (src0 == 0)
 165     return -1;
 166   return __builtin_clzl (src0);
 167 }
 168
 169 uint32_t
 170 __hsail_firstbit_s64 (int64_t src0)
 171 {
 172   uint64_t converted = src0 >= 0 ? src0 : ~src0;
 173   return __hsail_firstbit_u64 (converted);
 174 }
 175
 176 uint32_t
 177 __hsail_lastbit_u32 (uint32_t src0)
 178 {
 179   if (src0 == 0)
 180     return -1;
 181   return __builtin_ctz (src0);
 182 }
 183
 184 uint32_t
 185 __hsail_lastbit_u64 (uint64_t src0)
 186 {
 187   if (src0 == 0)
 188     return -1;
 189   return __builtin_ctzl (src0);
 190 }