libtcc1.c

   1 /* TCC runtime library.
   2    Parts of this code are (c) 2002 Fabrice Bellard
   3
   4    Copyright (C) 1987, 1988, 1992, 1994, 1995 Free Software Foundation, Inc.
   5
   6 This file is free software; you can redistribute it and/or modify it
   7 under the terms of the GNU General Public License as published by the
   8 Free Software Foundation; either version 2, or (at your option) any
   9 later version.
  10
  11 In addition to the permissions in the GNU General Public License, the
  12 Free Software Foundation gives you unlimited permission to link the
  13 compiled version of this file into combinations with other programs,
  14 and to distribute those combinations without any restriction coming
  15 from the use of this file.  (The General Public License restrictions
  16 do apply in other respects; for example, they cover modification of
  17 the file, and distribution when not linked into a combine
  18 executable.)
  19
  20 This file is distributed in the hope that it will be useful, but
  21 WITHOUT ANY WARRANTY; without even the implied warranty of
  22 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  23 General Public License for more details.
  24
  25 You should have received a copy of the GNU General Public License
  26 along with this program; see the file COPYING.  If not, write to
  27 the Free Software Foundation, 59 Temple Place - Suite 330,
  28 Boston, MA 02111-1307, USA.
  29 */
  30
  31 #define W_TYPE_SIZE   32
  32 #define BITS_PER_UNIT 8
  33
  34 typedef int Wtype;
  35 typedef unsigned int UWtype;
  36 typedef unsigned int USItype;
  37 typedef long long DWtype;
  38 typedef unsigned long long UDWtype;
  39
  40 struct DWstruct {
  41     Wtype low, high;
  42 };
  43
  44 typedef union
  45 {
  46   struct DWstruct s;
  47   DWtype ll;
  48 } DWunion;
  49
  50 typedef long double XFtype;
  51 #define WORD_SIZE (sizeof (Wtype) * BITS_PER_UNIT)
  52 #define HIGH_WORD_COEFF (((UDWtype) 1) << WORD_SIZE)
  53
  54 /* the following deal with IEEE single-precision numbers */
  55 #define EXCESS          126
  56 #define SIGNBIT         0x80000000
  57 #define HIDDEN          (1 << 23)
  58 #define SIGN(fp)        ((fp) & SIGNBIT)
  59 #define EXP(fp)         (((fp) >> 23) & 0xFF)
  60 #define MANT(fp)        (((fp) & 0x7FFFFF) | HIDDEN)
  61 #define PACK(s,e,m)     ((s) | ((e) << 23) | (m))
  62
  63 /* the following deal with IEEE double-precision numbers */
  64 #define EXCESSD         1022
  65 #define HIDDEND         (1 << 20)
  66 #define EXPD(fp)        (((fp.l.upper) >> 20) & 0x7FF)
  67 #define SIGND(fp)       ((fp.l.upper) & SIGNBIT)
  68 #define MANTD(fp)       (((((fp.l.upper) & 0xFFFFF) | HIDDEND) << 10) | \
  69                                 (fp.l.lower >> 22))
  70 #define HIDDEND_LL      ((long long)1 << 52)
  71 #define MANTD_LL(fp)    ((fp.ll & (HIDDEND_LL-1)) | HIDDEND_LL)
  72 #define PACKD_LL(s,e,m) (((long long)((s)+((e)<<20))<<32)|(m))
  73
  74 /* the following deal with x86 long double-precision numbers */
  75 #define EXCESSLD        16382
  76 #define EXPLD(fp)       (fp.l.upper & 0x7fff)
  77 #define SIGNLD(fp)      ((fp.l.upper) & 0x8000)
  78
  79 /* only for x86 */
  80 union ldouble_long {
  81     long double ld;
  82     struct {
  83         unsigned long long lower;
  84         unsigned short upper;
  85     } l;
  86 };
  87
  88 union double_long {
  89     double d;
  90 #if 1
  91     struct {
  92         unsigned long lower;
  93         long upper;
  94     } l;
  95 #else
  96     struct {
  97         long upper;
  98         unsigned long lower;
  99     } l;
 100 #endif
 101     long long ll;
 102 };
 103
 104 union float_long {
 105     float f;
 106     long l;
 107 };
 108
 109 /* XXX: use gcc/tcc intrinsic ? */
 110 #if defined(__i386__)
 111 #define sub_ddmmss(sh, sl, ah, al, bh, bl) \
 112   __asm__ ("subl %5,%1\n\tsbbl %3,%0"                                   \
 113            : "=r" ((USItype) (sh)),                                     \
 114              "=&r" ((USItype) (sl))                                     \
 115            : "0" ((USItype) (ah)),                                      \
 116              "g" ((USItype) (bh)),                                      \
 117              "1" ((USItype) (al)),                                      \
 118              "g" ((USItype) (bl)))
 119 #define umul_ppmm(w1, w0, u, v) \
 120   __asm__ ("mull %3"                                                    \
 121            : "=a" ((USItype) (w0)),                                     \
 122              "=d" ((USItype) (w1))                                      \
 123            : "%0" ((USItype) (u)),                                      \
 124              "rm" ((USItype) (v)))
 125 #define udiv_qrnnd(q, r, n1, n0, dv) \
 126   __asm__ ("divl %4"                                                    \
 127            : "=a" ((USItype) (q)),                                      \
 128              "=d" ((USItype) (r))                                       \
 129            : "0" ((USItype) (n0)),                                      \
 130              "1" ((USItype) (n1)),                                      \
 131              "rm" ((USItype) (dv)))
 132 #define count_leading_zeros(count, x) \
 133   do {                                                                  \
 134     USItype __cbtmp;                                                    \
 135     __asm__ ("bsrl %1,%0"                                               \
 136              : "=r" (__cbtmp) : "rm" ((USItype) (x)));                  \
 137     (count) = __cbtmp ^ 31;                                             \
 138   } while (0)
 139 #else
 140 #error unsupported CPU type
 141 #endif
 142
 143 /* most of this code is taken from libgcc2.c from gcc */
 144
 145 static UDWtype __udivmoddi4 (UDWtype n, UDWtype d, UDWtype *rp)
 146 {
 147   DWunion ww;
 148   DWunion nn, dd;
 149   DWunion rr;
 150   UWtype d0, d1, n0, n1, n2;
 151   UWtype q0, q1;
 152   UWtype b, bm;
 153
 154   nn.ll = n;
 155   dd.ll = d;
 156
 157   d0 = dd.s.low;
 158   d1 = dd.s.high;
 159   n0 = nn.s.low;
 160   n1 = nn.s.high;
 161
 162 #if !UDIV_NEEDS_NORMALIZATION
 163   if (d1 == 0)
 164     {
 165       if (d0 > n1)
 166         {
 167           /* 0q = nn / 0D */
 168
 169           udiv_qrnnd (q0, n0, n1, n0, d0);
 170           q1 = 0;
 171
 172           /* Remainder in n0.  */
 173         }
 174       else
 175         {
 176           /* qq = NN / 0d */
 177
 178           if (d0 == 0)
 179             d0 = 1 / d0;        /* Divide intentionally by zero.  */
 180
 181           udiv_qrnnd (q1, n1, 0, n1, d0);
 182           udiv_qrnnd (q0, n0, n1, n0, d0);
 183
 184           /* Remainder in n0.  */
 185         }
 186
 187       if (rp != 0)
 188         {
 189           rr.s.low = n0;
 190           rr.s.high = 0;
 191           *rp = rr.ll;
 192         }
 193     }
 194
 195 #else /* UDIV_NEEDS_NORMALIZATION */
 196
 197   if (d1 == 0)
 198     {
 199       if (d0 > n1)
 200         {
 201           /* 0q = nn / 0D */
 202
 203           count_leading_zeros (bm, d0);
 204
 205           if (bm != 0)
 206             {
 207               /* Normalize, i.e. make the most significant bit of the
 208                  denominator set.  */
 209
 210               d0 = d0 << bm;
 211               n1 = (n1 << bm) | (n0 >> (W_TYPE_SIZE - bm));
 212               n0 = n0 << bm;
 213             }
 214
 215           udiv_qrnnd (q0, n0, n1, n0, d0);
 216           q1 = 0;
 217
 218           /* Remainder in n0 >> bm.  */
 219         }
 220       else
 221         {
 222           /* qq = NN / 0d */
 223
 224           if (d0 == 0)
 225             d0 = 1 / d0;        /* Divide intentionally by zero.  */
 226
 227           count_leading_zeros (bm, d0);
 228
 229           if (bm == 0)
 230             {
 231               /* From (n1 >= d0) /\ (the most significant bit of d0 is set),
 232                  conclude (the most significant bit of n1 is set) /\ (the
 233                  leading quotient digit q1 = 1).
 234
 235                  This special case is necessary, not an optimization.
 236                  (Shifts counts of W_TYPE_SIZE are undefined.)  */
 237
 238               n1 -= d0;
 239               q1 = 1;
 240             }
 241           else
 242             {
 243               /* Normalize.  */
 244
 245               b = W_TYPE_SIZE - bm;
 246
 247               d0 = d0 << bm;
 248               n2 = n1 >> b;
 249               n1 = (n1 << bm) | (n0 >> b);
 250               n0 = n0 << bm;
 251
 252               udiv_qrnnd (q1, n1, n2, n1, d0);
 253             }
 254
 255           /* n1 != d0...  */
 256
 257           udiv_qrnnd (q0, n0, n1, n0, d0);
 258
 259           /* Remainder in n0 >> bm.  */
 260         }
 261
 262       if (rp != 0)
 263         {
 264           rr.s.low = n0 >> bm;
 265           rr.s.high = 0;
 266           *rp = rr.ll;
 267         }
 268     }
 269 #endif /* UDIV_NEEDS_NORMALIZATION */
 270
 271   else
 272     {
 273       if (d1 > n1)
 274         {
 275           /* 00 = nn / DD */
 276
 277           q0 = 0;
 278           q1 = 0;
 279
 280           /* Remainder in n1n0.  */
 281           if (rp != 0)
 282             {
 283               rr.s.low = n0;
 284               rr.s.high = n1;
 285               *rp = rr.ll;
 286             }
 287         }
 288       else
 289         {
 290           /* 0q = NN / dd */
 291
 292           count_leading_zeros (bm, d1);
 293           if (bm == 0)
 294             {
 295               /* From (n1 >= d1) /\ (the most significant bit of d1 is set),
 296                  conclude (the most significant bit of n1 is set) /\ (the
 297                  quotient digit q0 = 0 or 1).
 298
 299                  This special case is necessary, not an optimization.  */
 300
 301               /* The condition on the next line takes advantage of that
 302                  n1 >= d1 (true due to program flow).  */
 303               if (n1 > d1 || n0 >= d0)
 304                 {
 305                   q0 = 1;
 306                   sub_ddmmss (n1, n0, n1, n0, d1, d0);
 307                 }
 308               else
 309                 q0 = 0;
 310
 311               q1 = 0;
 312
 313               if (rp != 0)
 314                 {
 315                   rr.s.low = n0;
 316                   rr.s.high = n1;
 317                   *rp = rr.ll;
 318                 }
 319             }
 320           else
 321             {
 322               UWtype m1, m0;
 323               /* Normalize.  */
 324
 325               b = W_TYPE_SIZE - bm;
 326
 327               d1 = (d1 << bm) | (d0 >> b);
 328               d0 = d0 << bm;
 329               n2 = n1 >> b;
 330               n1 = (n1 << bm) | (n0 >> b);
 331               n0 = n0 << bm;
 332
 333               udiv_qrnnd (q0, n1, n2, n1, d1);
 334               umul_ppmm (m1, m0, q0, d0);
 335
 336               if (m1 > n1 || (m1 == n1 && m0 > n0))
 337                 {
 338                   q0--;
 339                   sub_ddmmss (m1, m0, m1, m0, d1, d0);
 340                 }
 341
 342               q1 = 0;
 343
 344               /* Remainder in (n1n0 - m1m0) >> bm.  */
 345               if (rp != 0)
 346                 {
 347                   sub_ddmmss (n1, n0, n1, n0, m1, m0);
 348                   rr.s.low = (n1 << b) | (n0 >> bm);
 349                   rr.s.high = n1 >> bm;
 350                   *rp = rr.ll;
 351                 }
 352             }
 353         }
 354     }
 355
 356   ww.s.low = q0;
 357   ww.s.high = q1;
 358   return ww.ll;
 359 }
 360
 361 #define __negdi2(a) (-(a))
 362
 363 long long __divdi3(long long u, long long v)
 364 {
 365     int c = 0;
 366     DWunion uu, vv;
 367     DWtype w;
 368
 369     uu.ll = u;
 370     vv.ll = v;
 371
 372     if (uu.s.high < 0) {
 373         c = ~c;
 374         uu.ll = __negdi2 (uu.ll);
 375     }
 376     if (vv.s.high < 0) {
 377         c = ~c;
 378         vv.ll = __negdi2 (vv.ll);
 379     }
 380     w = __udivmoddi4 (uu.ll, vv.ll, (UDWtype *) 0);
 381     if (c)
 382         w = __negdi2 (w);
 383     return w;
 384 }
 385
 386 long long __moddi3(long long u, long long v)
 387 {
 388     int c = 0;
 389     DWunion uu, vv;
 390     DWtype w;
 391
 392     uu.ll = u;
 393     vv.ll = v;
 394
 395     if (uu.s.high < 0) {
 396         c = ~c;
 397         uu.ll = __negdi2 (uu.ll);
 398     }
 399     if (vv.s.high < 0)
 400         vv.ll = __negdi2 (vv.ll);
 401
 402     __udivmoddi4 (uu.ll, vv.ll, &w);
 403     if (c)
 404         w = __negdi2 (w);
 405     return w;
 406 }
 407
 408 unsigned long long __udivdi3(unsigned long long u, unsigned long long v)
 409 {
 410     return __udivmoddi4 (u, v, (UDWtype *) 0);
 411 }
 412
 413 unsigned long long __umoddi3(unsigned long long u, unsigned long long v)
 414 {
 415     UDWtype w;
 416
 417     __udivmoddi4 (u, v, &w);
 418     return w;
 419 }
 420
 421 /* XXX: fix tcc's code generator to do this instead */
 422 long long __sardi3(long long a, int b)
 423 {
 424     return a >> b;
 425 }
 426
 427 /* XXX: fix tcc's code generator to do this instead */
 428 unsigned long long __shrdi3(unsigned long long a, int b)
 429 {
 430     return a >> b;
 431 }
 432
 433 /* XXX: fix tcc's code generator to do this instead */
 434 long long __shldi3(long long a, int b)
 435 {
 436     return a << b;
 437 }
 438
 439 #if defined(__i386__)
 440 /* FPU control word for rounding to nearest mode */
 441 unsigned short __tcc_fpu_control = 0x137f;
 442 /* FPU control word for round to zero mode for int conversion */
 443 unsigned short __tcc_int_fpu_control = 0x137f | 0x0c00;
 444 #endif
 445
 446 /* XXX: fix tcc's code generator to do this instead */
 447 float __ulltof(unsigned long long a)
 448 {
 449     DWunion uu;
 450     XFtype r;
 451
 452     uu.ll = a;
 453     if (uu.s.high >= 0) {
 454         return (float)uu.ll;
 455     } else {
 456         r = (XFtype)uu.ll;
 457         r += 18446744073709551616.0;
 458         return (float)r;
 459     }
 460 }
 461
 462 double __ulltod(unsigned long long a)
 463 {
 464     DWunion uu;
 465     XFtype r;
 466
 467     uu.ll = a;
 468     if (uu.s.high >= 0) {
 469         return (double)uu.ll;
 470     } else {
 471         r = (XFtype)uu.ll;
 472         r += 18446744073709551616.0;
 473         return (double)r;
 474     }
 475 }
 476
 477 long double __ulltold(unsigned long long a)
 478 {
 479     DWunion uu;
 480     XFtype r;
 481
 482     uu.ll = a;
 483     if (uu.s.high >= 0) {
 484         return (long double)uu.ll;
 485     } else {
 486         r = (XFtype)uu.ll;
 487         r += 18446744073709551616.0;
 488         return (long double)r;
 489     }
 490 }
 491
 492 unsigned long long __fixunssfdi (float a1)
 493 {
 494     register union float_long fl1;
 495     register int exp;
 496     register unsigned long l;
 497
 498     fl1.f = a1;
 499
 500     if (fl1.l == 0)
 501         return (0);
 502
 503     exp = EXP (fl1.l) - EXCESS - 24;
 504
 505     l = MANT(fl1.l);
 506     if (exp >= 41)
 507         return (unsigned long long)-1;
 508     else if (exp >= 0)
 509         return (unsigned long long)l << exp;
 510     else if (exp >= -23)
 511         return l >> -exp;
 512     else
 513         return 0;
 514 }
 515
 516 unsigned long long __fixunsdfdi (double a1)
 517 {
 518     register union double_long dl1;
 519     register int exp;
 520     register unsigned long long l;
 521
 522     dl1.d = a1;
 523
 524     if (dl1.ll == 0)
 525         return (0);
 526
 527     exp = EXPD (dl1) - EXCESSD - 53;
 528
 529     l = MANTD_LL(dl1);
 530
 531     if (exp >= 12)
 532         return (unsigned long long)-1;
 533     else if (exp >= 0)
 534         return l << exp;
 535     else if (exp >= -52)
 536         return l >> -exp;
 537     else
 538         return 0;
 539 }
 540
 541 unsigned long long __fixunsxfdi (long double a1)
 542 {
 543     register union ldouble_long dl1;
 544     register int exp;
 545     register unsigned long long l;
 546
 547     dl1.ld = a1;
 548
 549     if (dl1.l.lower == 0 && dl1.l.upper == 0)
 550         return (0);
 551
 552     exp = EXPLD (dl1) - EXCESSLD - 64;
 553
 554     l = dl1.l.lower;
 555
 556     if (exp > 0)
 557         return (unsigned long long)-1;
 558     else if (exp >= -63)
 559         return l >> -exp;
 560     else
 561         return 0;
 562 }
 563