libgcc/config/stormy16/lib2funcs.c

   1 /* This file contains 16-bit versions of some of the functions found in
   2    libgcc2.c.  Really libgcc ought to be moved out of the gcc directory
   3    and into its own top level directory, and then split up into multiple
   4    files.  On this glorious day maybe this code can be integrated into
   5    it too.  */
   6
   7 /* Copyright (C) 2005, 2008, 2009, 2010, 2011  Free Software Foundation, Inc.
   8
   9    This file is part of GCC.
  10
  11    GCC is free software; you can redistribute it and/or modify it under
  12    the terms of the GNU General Public License as published by the Free
  13    Software Foundation; either version 3, or (at your option) any later
  14    version.
  15
  16    GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  17    WARRANTY; without even the implied warranty of MERCHANTABILITY or
  18    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  19    for more details.
  20
  21    Under Section 7 of GPL version 3, you are granted additional
  22    permissions described in the GCC Runtime Library Exception, version
  23    3.1, as published by the Free Software Foundation.
  24
  25    You should have received a copy of the GNU General Public License and
  26    a copy of the GCC Runtime Library Exception along with this program;
  27    see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
  28    <http://www.gnu.org/licenses/>.  */
  29
  30 #include "tconfig.h"
  31 #include "tsystem.h"
  32 #include "coretypes.h"
  33 #include "tm.h"
  34 #include "libgcc_tm.h"
  35
  36 #ifdef HAVE_GAS_HIDDEN
  37 #define ATTRIBUTE_HIDDEN  __attribute__ ((__visibility__ ("hidden")))
  38 #else
  39 #define ATTRIBUTE_HIDDEN
  40 #endif
  41
  42 #ifndef MIN_UNITS_PER_WORD
  43 #define MIN_UNITS_PER_WORD UNITS_PER_WORD
  44 #endif
  45
  46 #ifndef LIBGCC2_UNITS_PER_WORD
  47 # if MIN_UNITS_PER_WORD > 4
  48 #  define LIBGCC2_UNITS_PER_WORD 8
  49 # elif (MIN_UNITS_PER_WORD > 2 \
  50         || (MIN_UNITS_PER_WORD > 1 && LONG_LONG_TYPE_SIZE > 32))
  51 #  define LIBGCC2_UNITS_PER_WORD 4
  52 # else
  53 #  define LIBGCC2_UNITS_PER_WORD MIN_UNITS_PER_WORD
  54 # endif
  55 #endif
  56
  57 #define word_type Wtype
  58
  59 #include "libgcc2.h"
  60 #undef int
  61
  62 /* These prototypes would normally live in libgcc2.h, but this can
  63    only happen once the code below is integrated into libgcc2.c.  */
  64
  65 extern USItype udivmodsi4 (USItype, USItype, word_type);
  66 extern SItype __divsi3 (SItype, SItype);
  67 extern SItype __modsi3 (SItype, SItype);
  68 extern SItype __udivsi3 (SItype, SItype);
  69 extern SItype __umodsi3 (SItype, SItype);
  70 extern SItype __ashlsi3 (SItype, SItype);
  71 extern SItype __ashrsi3 (SItype, SItype);
  72 extern USItype __lshrsi3 (USItype, USItype);
  73 extern int __popcounthi2 (UHWtype);
  74 extern int __parityhi2 (UHWtype);
  75 extern int __clzhi2 (UHWtype);
  76 extern int __ctzhi2 (UHWtype);
  77
  78
  79 #ifdef XSTORMY16_UDIVMODSI4
  80 USItype
  81 udivmodsi4 (USItype num, USItype den, word_type modwanted)
  82 {
  83   USItype bit = 1;
  84   USItype res = 0;
  85
  86   while (den < num && bit && !(den & (1L << 31)))
  87     {
  88       den <<= 1;
  89       bit <<= 1;
  90     }
  91   while (bit)
  92     {
  93       if (num >= den)
  94         {
  95           num -= den;
  96           res |= bit;
  97         }
  98       bit >>= 1;
  99       den >>= 1;
 100     }
 101
 102   if (modwanted)
 103     return num;
 104   return res;
 105 }
 106 #endif
 107
 108 #ifdef XSTORMY16_DIVSI3
 109 SItype
 110 __divsi3 (SItype a, SItype b)
 111 {
 112   word_type neg = 0;
 113   SItype res;
 114
 115   if (a < 0)
 116     {
 117       a = -a;
 118       neg = !neg;
 119     }
 120
 121   if (b < 0)
 122     {
 123       b = -b;
 124       neg = !neg;
 125     }
 126
 127   res = udivmodsi4 (a, b, 0);
 128
 129   if (neg)
 130     res = -res;
 131
 132   return res;
 133 }
 134 #endif
 135
 136 #ifdef XSTORMY16_MODSI3
 137 SItype
 138 __modsi3 (SItype a, SItype b)
 139 {
 140   word_type neg = 0;
 141   SItype res;
 142
 143   if (a < 0)
 144     {
 145       a = -a;
 146       neg = 1;
 147     }
 148
 149   if (b < 0)
 150     b = -b;
 151
 152   res = udivmodsi4 (a, b, 1);
 153
 154   if (neg)
 155     res = -res;
 156
 157   return res;
 158 }
 159 #endif
 160
 161 #ifdef XSTORMY16_UDIVSI3
 162 SItype
 163 __udivsi3 (SItype a, SItype b)
 164 {
 165   return udivmodsi4 (a, b, 0);
 166 }
 167 #endif
 168
 169 #ifdef XSTORMY16_UMODSI3
 170 SItype
 171 __umodsi3 (SItype a, SItype b)
 172 {
 173   return udivmodsi4 (a, b, 1);
 174 }
 175 #endif
 176
 177 #ifdef XSTORMY16_ASHLSI3
 178 SItype
 179 __ashlsi3 (SItype a, SItype b)
 180 {
 181   word_type i;
 182
 183   if (b & 16)
 184     a <<= 16;
 185   if (b & 8)
 186     a <<= 8;
 187   for (i = (b & 0x7); i > 0; --i)
 188     a <<= 1;
 189   return a;
 190 }
 191 #endif
 192
 193 #ifdef XSTORMY16_ASHRSI3
 194 SItype
 195 __ashrsi3 (SItype a, SItype b)
 196 {
 197   word_type i;
 198
 199   if (b & 16)
 200     a >>= 16;
 201   if (b & 8)
 202     a >>= 8;
 203   for (i = (b & 0x7); i > 0; --i)
 204     a >>= 1;
 205   return a;
 206 }
 207 #endif
 208
 209 #ifdef XSTORMY16_LSHRSI3
 210 USItype
 211 __lshrsi3 (USItype a, USItype b)
 212 {
 213   word_type i;
 214
 215   if (b & 16)
 216     a >>= 16;
 217   if (b & 8)
 218     a >>= 8;
 219   for (i = (b & 0x7); i > 0; --i)
 220     a >>= 1;
 221   return a;
 222 }
 223 #endif
 224
 225 #ifdef XSTORMY16_POPCOUNTHI2
 226 /* Returns the number of set bits in X.
 227    FIXME:  The return type really should be "unsigned int"
 228    but this is not how the builtin is prototyped.  */
 229 int
 230 __popcounthi2 (UHWtype x)
 231 {
 232   int ret;
 233
 234   ret = __popcount_tab [x & 0xff];
 235   ret += __popcount_tab [(x >> 8) & 0xff];
 236
 237   return ret;
 238 }
 239 #endif
 240
 241 #ifdef XSTORMY16_PARITYHI2
 242 /* Returns the number of set bits in X, modulo 2.
 243    FIXME:  The return type really should be "unsigned int"
 244    but this is not how the builtin is prototyped.  */
 245
 246 int
 247 __parityhi2 (UHWtype x)
 248 {
 249   x ^= x >> 8;
 250   x ^= x >> 4;
 251   x &= 0xf;
 252   return (0x6996 >> x) & 1;
 253 }
 254 #endif
 255
 256 #ifdef XSTORMY16_CLZHI2
 257 /* Returns the number of zero-bits from the most significant bit to the
 258    first nonzero bit in X.  Returns 16 for X == 0.  Implemented as a
 259    simple for loop in order to save space by removing the need for
 260    the __clz_tab array.
 261    FIXME:  The return type really should be "unsigned int" but this is
 262    not how the builtin is prototyped.  */
 263 #undef unsigned
 264 int
 265 __clzhi2 (UHWtype x)
 266 {
 267   unsigned int i;
 268   unsigned int c;
 269   unsigned int value = x;
 270
 271   for (c = 0, i = 1 << 15; i; i >>= 1, c++)
 272     if (i & value)
 273       break;
 274   return c;
 275 }
 276 #endif
 277
 278 #ifdef XSTORMY16_CTZHI2
 279 /* Returns the number of trailing zero bits in X.
 280    FIXME:  The return type really should be "signed int" since
 281    ctz(0) returns -1, but this is not how the builtin is prototyped.  */
 282
 283 int
 284 __ctzhi2 (UHWtype x)
 285 {
 286   /* This is cunning.  It converts X into a number with only the one bit
 287      set, the bit that was the least significant bit in X.  From this we
 288      can use the count_leading_zeros to compute the number of trailing
 289      bits.  */
 290   x &= - x;
 291
 292   return 15 - __builtin_clz (x);
 293 }
 294 #endif
 295
 296 #ifdef XSTORMY16_FFSHI2
 297 /* Returns one plus the index of the least significant 1-bit of X,
 298    or if X is zero, returns zero.  FIXME:  The return type really
 299    should be "unsigned int" but this is not how the builtin is
 300    prototyped.  */
 301
 302 int
 303 __ffshi2 (UHWtype u)
 304 {
 305   UHWtype count;
 306
 307   if (u == 0)
 308     return 0;
 309
 310   return 16 - __builtin_clz (u & - u);
 311 }
 312 #endif
 313
 314 #ifdef XSTORMY16_UCMPSI2
 315 /* Performs an unsigned comparison of two 32-bit values: A and B.
 316    If A is less than B, then 0 is returned.  If A is greater than B,
 317    then 2 is returned.  Otherwise A and B are equal and 1 is returned.  */
 318
 319 word_type
 320 __ucmpsi2 (USItype a, USItype b)
 321 {
 322   word_type hi_a = (a >> 16);
 323   word_type hi_b = (b >> 16);
 324
 325   if (hi_a == hi_b)
 326     {
 327       word_type low_a = (a & 0xffff);
 328       word_type low_b = (b & 0xffff);
 329
 330       return low_a < low_b ? 0 : (low_a > low_b ? 2 : 1);
 331     }
 332
 333   return hi_a < hi_b ? 0 : 2;
 334 }
 335 #endif
 336
 337 #ifdef XSTORMY16_CMPSI2
 338 /* Performs an signed comparison of two 32-bit values: A and B.
 339    If A is less than B, then 0 is returned.  If A is greater than B,
 340    then 2 is returned.  Otherwise A and B are equal and 1 is returned.  */
 341
 342 word_type
 343 __cmpsi2 (SItype a, SItype b)
 344 {
 345   word_type hi_a = (a >> 16);
 346   word_type hi_b = (b >> 16);
 347
 348   if (hi_a == hi_b)
 349     {
 350       word_type low_a = (a & 0xffff);
 351       word_type low_b = (b & 0xffff);
 352
 353       return low_a < low_b ? 0 : (low_a > low_b ? 2 : 1);
 354     }
 355
 356   return hi_a < hi_b ? 0 : 2;
 357 }
 358 #endif