dlls/msvcrt/math.c

   1 /*
   2  * msvcrt.dll math functions
   3  *
   4  * Copyright 2000 Jon Griffiths
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  19  */
  20 #include "config.h"
  21
  22 #include <stdio.h>
  23 #define __USE_ISOC9X 1
  24 #define __USE_ISOC99 1
  25 #include <math.h>
  26 #ifdef HAVE_IEEEFP_H
  27 #include <ieeefp.h>
  28 #endif
  29
  30 #include "msvcrt.h"
  31
  32 #include "wine/debug.h"
  33
  34 WINE_DEFAULT_DEBUG_CHANNEL(msvcrt);
  35
  36 #ifndef HAVE_FINITE
  37 #ifndef finite /* Could be a macro */
  38 #ifdef isfinite
  39 #define finite(x) isfinite(x)
  40 #else
  41 #define finite(x) (!isnan(x)) /* At least catch some cases */
  42 #endif
  43 #endif
  44 #endif
  45
  46 #ifndef signbit
  47 #define signbit(x) 0
  48 #endif
  49
  50 typedef int (*MSVCRT_matherr_func)(struct MSVCRT__exception *);
  51
  52 static MSVCRT_matherr_func MSVCRT_default_matherr_func = NULL;
  53
  54 /*********************************************************************
  55  *              MSVCRT_acos (MSVCRT.@)
  56  */
  57 double CDECL MSVCRT_acos( double x )
  58 {
  59   if (x < -1.0 || x > 1.0 || !finite(x)) *MSVCRT__errno() = MSVCRT_EDOM;
  60   /* glibc implements acos() as the FPU equivalent of atan2(sqrt(1 - x ^ 2), x).
  61    * asin() uses a similar construction. This is bad because as x gets nearer to
  62    * 1 the error in the expression "1 - x^2" can get relatively large due to
  63    * cancellation. The sqrt() makes things worse. A safer way to calculate
  64    * acos() is to use atan2(sqrt((1 - x) * (1 + x)), x). */
  65   return atan2(sqrt((1 - x) * (1 + x)), x);
  66 }
  67
  68 /*********************************************************************
  69  *              MSVCRT_asin (MSVCRT.@)
  70  */
  71 double CDECL MSVCRT_asin( double x )
  72 {
  73   if (x < -1.0 || x > 1.0 || !finite(x)) *MSVCRT__errno() = MSVCRT_EDOM;
  74   return atan2(x, sqrt((1 - x) * (1 + x)));
  75 }
  76
  77 /*********************************************************************
  78  *              MSVCRT_atan (MSVCRT.@)
  79  */
  80 double CDECL MSVCRT_atan( double x )
  81 {
  82   if (!finite(x)) *MSVCRT__errno() = MSVCRT_EDOM;
  83   return atan(x);
  84 }
  85
  86 /*********************************************************************
  87  *              MSVCRT_atan2 (MSVCRT.@)
  88  */
  89 double CDECL MSVCRT_atan2( double x, double y )
  90 {
  91   if (!finite(x)) *MSVCRT__errno() = MSVCRT_EDOM;
  92   return atan2(x,y);
  93 }
  94
  95 /*********************************************************************
  96  *              MSVCRT_cos (MSVCRT.@)
  97  */
  98 double CDECL MSVCRT_cos( double x )
  99 {
 100   if (!finite(x)) *MSVCRT__errno() = MSVCRT_EDOM;
 101   return cos(x);
 102 }
 103
 104 /*********************************************************************
 105  *              MSVCRT_cosh (MSVCRT.@)
 106  */
 107 double CDECL MSVCRT_cosh( double x )
 108 {
 109   if (!finite(x)) *MSVCRT__errno() = MSVCRT_EDOM;
 110   return cosh(x);
 111 }
 112
 113 /*********************************************************************
 114  *              MSVCRT_exp (MSVCRT.@)
 115  */
 116 double CDECL MSVCRT_exp( double x )
 117 {
 118   if (!finite(x)) *MSVCRT__errno() = MSVCRT_EDOM;
 119   return exp(x);
 120 }
 121
 122 /*********************************************************************
 123  *              MSVCRT_fmod (MSVCRT.@)
 124  */
 125 double CDECL MSVCRT_fmod( double x, double y )
 126 {
 127   if (!finite(x) || !finite(y)) *MSVCRT__errno() = MSVCRT_EDOM;
 128   return fmod(x,y);
 129 }
 130
 131 /*********************************************************************
 132  *              MSVCRT_log (MSVCRT.@)
 133  */
 134 double CDECL MSVCRT_log( double x)
 135 {
 136   if (x < 0.0 || !finite(x)) *MSVCRT__errno() = MSVCRT_EDOM;
 137   if (x == 0.0) *MSVCRT__errno() = MSVCRT_ERANGE;
 138   return log(x);
 139 }
 140
 141 /*********************************************************************
 142  *              MSVCRT_log10 (MSVCRT.@)
 143  */
 144 double CDECL MSVCRT_log10( double x )
 145 {
 146   if (x < 0.0 || !finite(x)) *MSVCRT__errno() = MSVCRT_EDOM;
 147   if (x == 0.0) *MSVCRT__errno() = MSVCRT_ERANGE;
 148   return log10(x);
 149 }
 150
 151 /*********************************************************************
 152  *              MSVCRT_pow (MSVCRT.@)
 153  */
 154 double CDECL MSVCRT_pow( double x, double y )
 155 {
 156   /* FIXME: If x < 0 and y is not integral, set EDOM */
 157   double z = pow(x,y);
 158   if (!finite(z)) *MSVCRT__errno() = MSVCRT_EDOM;
 159   return z;
 160 }
 161
 162 /*********************************************************************
 163  *              MSVCRT_sin (MSVCRT.@)
 164  */
 165 double CDECL MSVCRT_sin( double x )
 166 {
 167   if (!finite(x)) *MSVCRT__errno() = MSVCRT_EDOM;
 168   return sin(x);
 169 }
 170
 171 /*********************************************************************
 172  *              MSVCRT_sinh (MSVCRT.@)
 173  */
 174 double CDECL MSVCRT_sinh( double x )
 175 {
 176   if (!finite(x)) *MSVCRT__errno() = MSVCRT_EDOM;
 177   return sinh(x);
 178 }
 179
 180 /*********************************************************************
 181  *              MSVCRT_sqrt (MSVCRT.@)
 182  */
 183 double CDECL MSVCRT_sqrt( double x )
 184 {
 185   if (x < 0.0 || !finite(x)) *MSVCRT__errno() = MSVCRT_EDOM;
 186   return sqrt(x);
 187 }
 188
 189 /*********************************************************************
 190  *              MSVCRT_tan (MSVCRT.@)
 191  */
 192 double CDECL MSVCRT_tan( double x )
 193 {
 194   if (!finite(x)) *MSVCRT__errno() = MSVCRT_EDOM;
 195   return tan(x);
 196 }
 197
 198 /*********************************************************************
 199  *              MSVCRT_tanh (MSVCRT.@)
 200  */
 201 double CDECL MSVCRT_tanh( double x )
 202 {
 203   if (!finite(x)) *MSVCRT__errno() = MSVCRT_EDOM;
 204   return tanh(x);
 205 }
 206
 207
 208 #if defined(__GNUC__) && defined(__i386__)
 209
 210 #define FPU_DOUBLE(var) double var; \
 211   __asm__ __volatile__( "fstpl %0;fwait" : "=m" (var) : )
 212 #define FPU_DOUBLES(var1,var2) double var1,var2; \
 213   __asm__ __volatile__( "fstpl %0;fwait" : "=m" (var2) : ); \
 214   __asm__ __volatile__( "fstpl %0;fwait" : "=m" (var1) : )
 215
 216 /*********************************************************************
 217  *              _CIacos (MSVCRT.@)
 218  */
 219 double CDECL _CIacos(void)
 220 {
 221   FPU_DOUBLE(x);
 222   return MSVCRT_acos(x);
 223 }
 224
 225 /*********************************************************************
 226  *              _CIasin (MSVCRT.@)
 227  */
 228 double CDECL _CIasin(void)
 229 {
 230   FPU_DOUBLE(x);
 231   return MSVCRT_asin(x);
 232 }
 233
 234 /*********************************************************************
 235  *              _CIatan (MSVCRT.@)
 236  */
 237 double CDECL _CIatan(void)
 238 {
 239   FPU_DOUBLE(x);
 240   return MSVCRT_atan(x);
 241 }
 242
 243 /*********************************************************************
 244  *              _CIatan2 (MSVCRT.@)
 245  */
 246 double CDECL _CIatan2(void)
 247 {
 248   FPU_DOUBLES(x,y);
 249   return MSVCRT_atan2(x,y);
 250 }
 251
 252 /*********************************************************************
 253  *              _CIcos (MSVCRT.@)
 254  */
 255 double CDECL _CIcos(void)
 256 {
 257   FPU_DOUBLE(x);
 258   return MSVCRT_cos(x);
 259 }
 260
 261 /*********************************************************************
 262  *              _CIcosh (MSVCRT.@)
 263  */
 264 double CDECL _CIcosh(void)
 265 {
 266   FPU_DOUBLE(x);
 267   return MSVCRT_cosh(x);
 268 }
 269
 270 /*********************************************************************
 271  *              _CIexp (MSVCRT.@)
 272  */
 273 double CDECL _CIexp(void)
 274 {
 275   FPU_DOUBLE(x);
 276   return MSVCRT_exp(x);
 277 }
 278
 279 /*********************************************************************
 280  *              _CIfmod (MSVCRT.@)
 281  */
 282 double CDECL _CIfmod(void)
 283 {
 284   FPU_DOUBLES(x,y);
 285   return MSVCRT_fmod(x,y);
 286 }
 287
 288 /*********************************************************************
 289  *              _CIlog (MSVCRT.@)
 290  */
 291 double CDECL _CIlog(void)
 292 {
 293   FPU_DOUBLE(x);
 294   return MSVCRT_log(x);
 295 }
 296
 297 /*********************************************************************
 298  *              _CIlog10 (MSVCRT.@)
 299  */
 300 double CDECL _CIlog10(void)
 301 {
 302   FPU_DOUBLE(x);
 303   return MSVCRT_log10(x);
 304 }
 305
 306 /*********************************************************************
 307  *              _CIpow (MSVCRT.@)
 308  */
 309 double CDECL _CIpow(void)
 310 {
 311   FPU_DOUBLES(x,y);
 312   return MSVCRT_pow(x,y);
 313 }
 314
 315 /*********************************************************************
 316  *              _CIsin (MSVCRT.@)
 317  */
 318 double CDECL _CIsin(void)
 319 {
 320   FPU_DOUBLE(x);
 321   return MSVCRT_sin(x);
 322 }
 323
 324 /*********************************************************************
 325  *              _CIsinh (MSVCRT.@)
 326  */
 327 double CDECL _CIsinh(void)
 328 {
 329   FPU_DOUBLE(x);
 330   return MSVCRT_sinh(x);
 331 }
 332
 333 /*********************************************************************
 334  *              _CIsqrt (MSVCRT.@)
 335  */
 336 double CDECL _CIsqrt(void)
 337 {
 338   FPU_DOUBLE(x);
 339   return MSVCRT_sqrt(x);
 340 }
 341
 342 /*********************************************************************
 343  *              _CItan (MSVCRT.@)
 344  */
 345 double CDECL _CItan(void)
 346 {
 347   FPU_DOUBLE(x);
 348   return MSVCRT_tan(x);
 349 }
 350
 351 /*********************************************************************
 352  *              _CItanh (MSVCRT.@)
 353  */
 354 double CDECL _CItanh(void)
 355 {
 356   FPU_DOUBLE(x);
 357   return MSVCRT_tanh(x);
 358 }
 359
 360 #else /* defined(__GNUC__) && defined(__i386__) */
 361
 362 /* The above cannot be called on non x86 platforms, stub them for linking */
 363
 364 #define IX86_ONLY(func) double func(void) { return 0.0; }
 365
 366 IX86_ONLY(_CIacos)
 367 IX86_ONLY(_CIasin)
 368 IX86_ONLY(_CIatan)
 369 IX86_ONLY(_CIatan2)
 370 IX86_ONLY(_CIcos)
 371 IX86_ONLY(_CIcosh)
 372 IX86_ONLY(_CIexp)
 373 IX86_ONLY(_CIfmod)
 374 IX86_ONLY(_CIlog)
 375 IX86_ONLY(_CIlog10)
 376 IX86_ONLY(_CIpow)
 377 IX86_ONLY(_CIsin)
 378 IX86_ONLY(_CIsinh)
 379 IX86_ONLY(_CIsqrt)
 380 IX86_ONLY(_CItan)
 381 IX86_ONLY(_CItanh)
 382
 383 #endif /* defined(__GNUC__) && defined(__i386__) */
 384
 385 /*********************************************************************
 386  *              _fpclass (MSVCRT.@)
 387  */
 388 int CDECL _fpclass(double num)
 389 {
 390 #if defined(HAVE_FPCLASS) || defined(fpclass)
 391   switch (fpclass( num ))
 392   {
 393 #ifdef FP_SNAN
 394   case FP_SNAN:  return MSVCRT__FPCLASS_SNAN;
 395 #endif
 396 #ifdef FP_QNAN
 397   case FP_QNAN:  return MSVCRT__FPCLASS_QNAN;
 398 #endif
 399 #ifdef FP_NINF
 400   case FP_NINF:  return MSVCRT__FPCLASS_NINF;
 401 #endif
 402 #ifdef FP_PINF
 403   case FP_PINF:  return MSVCRT__FPCLASS_PINF;
 404 #endif
 405 #ifdef FP_NDENORM
 406   case FP_NDENORM: return MSVCRT__FPCLASS_ND;
 407 #endif
 408 #ifdef FP_PDENORM
 409   case FP_PDENORM: return MSVCRT__FPCLASS_PD;
 410 #endif
 411 #ifdef FP_NZERO
 412   case FP_NZERO: return MSVCRT__FPCLASS_NZ;
 413 #endif
 414 #ifdef FP_PZERO
 415   case FP_PZERO: return MSVCRT__FPCLASS_PZ;
 416 #endif
 417 #ifdef FP_NNORM
 418   case FP_NNORM: return MSVCRT__FPCLASS_NN;
 419 #endif
 420 #ifdef FP_PNORM
 421   case FP_PNORM: return MSVCRT__FPCLASS_PN;
 422 #endif
 423   default: return MSVCRT__FPCLASS_PN;
 424   }
 425 #elif defined (fpclassify)
 426   switch (fpclassify( num ))
 427   {
 428   case FP_NAN: return MSVCRT__FPCLASS_QNAN;
 429   case FP_INFINITE: return signbit(num) ? MSVCRT__FPCLASS_NINF : MSVCRT__FPCLASS_PINF;
 430   case FP_SUBNORMAL: return signbit(num) ?MSVCRT__FPCLASS_ND : MSVCRT__FPCLASS_PD;
 431   case FP_ZERO: return signbit(num) ? MSVCRT__FPCLASS_NZ : MSVCRT__FPCLASS_PZ;
 432   }
 433   return signbit(num) ? MSVCRT__FPCLASS_NN : MSVCRT__FPCLASS_PN;
 434 #else
 435   if (!finite(num))
 436     return MSVCRT__FPCLASS_QNAN;
 437   return num == 0.0 ? MSVCRT__FPCLASS_PZ : (num < 0 ? MSVCRT__FPCLASS_NN : MSVCRT__FPCLASS_PN);
 438 #endif
 439 }
 440
 441 /*********************************************************************
 442  *              _rotl (MSVCRT.@)
 443  */
 444 unsigned int CDECL _rotl(unsigned int num, int shift)
 445 {
 446   shift &= 31;
 447   return (num << shift) | (num >> (32-shift));
 448 }
 449
 450 /*********************************************************************
 451  *              _logb (MSVCRT.@)
 452  */
 453 double CDECL _logb(double num)
 454 {
 455   if (!finite(num)) *MSVCRT__errno() = MSVCRT_EDOM;
 456   return logb(num);
 457 }
 458
 459 /*********************************************************************
 460  *              _lrotl (MSVCRT.@)
 461  */
 462 unsigned long CDECL _lrotl(unsigned long num, int shift)
 463 {
 464   shift &= 0x1f;
 465   return (num << shift) | (num >> (32-shift));
 466 }
 467
 468 /*********************************************************************
 469  *              _lrotr (MSVCRT.@)
 470  */
 471 unsigned long CDECL _lrotr(unsigned long num, int shift)
 472 {
 473   shift &= 0x1f;
 474   return (num >> shift) | (num << (32-shift));
 475 }
 476
 477 /*********************************************************************
 478  *              _rotr (MSVCRT.@)
 479  */
 480 unsigned int CDECL _rotr(unsigned int num, int shift)
 481 {
 482     shift &= 0x1f;
 483     return (num >> shift) | (num << (32-shift));
 484 }
 485
 486 /*********************************************************************
 487  *              _scalb (MSVCRT.@)
 488  */
 489 double CDECL _scalb(double num, long power)
 490 {
 491   /* Note - Can't forward directly as libc expects y as double */
 492   double dblpower = (double)power;
 493   if (!finite(num)) *MSVCRT__errno() = MSVCRT_EDOM;
 494   return scalb(num, dblpower);
 495 }
 496
 497 /*********************************************************************
 498  *              _hypot (MSVCRT.@)
 499  */
 500 double CDECL _hypot(double x, double y)
 501 {
 502   /* FIXME: errno handling */
 503   return hypot( x, y );
 504 }
 505
 506 /*********************************************************************
 507  *              ceil (MSVCRT.@)
 508  */
 509 double CDECL MSVCRT_ceil( double x )
 510 {
 511   return ceil(x);
 512 }
 513
 514 /*********************************************************************
 515  *              floor (MSVCRT.@)
 516  */
 517 double CDECL MSVCRT_floor( double x )
 518 {
 519   return floor(x);
 520 }
 521
 522 /*********************************************************************
 523  *              fabs (MSVCRT.@)
 524  */
 525 double CDECL MSVCRT_fabs( double x )
 526 {
 527   return fabs(x);
 528 }
 529
 530 /*********************************************************************
 531  *              frexp (MSVCRT.@)
 532  */
 533 double CDECL MSVCRT_frexp( double x, int *exp )
 534 {
 535   return frexp( x, exp );
 536 }
 537
 538 /*********************************************************************
 539  *              modf (MSVCRT.@)
 540  */
 541 double CDECL MSVCRT_modf( double x, double *iptr )
 542 {
 543   return modf( x, iptr );
 544 }
 545
 546 /*********************************************************************
 547  *              _matherr (MSVCRT.@)
 548  */
 549 int CDECL MSVCRT__matherr(struct MSVCRT__exception *e)
 550 {
 551   if (e)
 552     TRACE("(%p = %d, %s, %g %g %g)\n",e, e->type, e->name, e->arg1, e->arg2,
 553           e->retval);
 554   else
 555     TRACE("(null)\n");
 556   if (MSVCRT_default_matherr_func)
 557     return MSVCRT_default_matherr_func(e);
 558   ERR(":Unhandled math error!\n");
 559   return 0;
 560 }
 561
 562 /*********************************************************************
 563  *              __setusermatherr (MSVCRT.@)
 564  */
 565 void CDECL MSVCRT___setusermatherr(MSVCRT_matherr_func func)
 566 {
 567   MSVCRT_default_matherr_func = func;
 568   TRACE(":new matherr handler %p\n", func);
 569 }
 570
 571 /**********************************************************************
 572  *              _statusfp (MSVCRT.@)
 573  */
 574 unsigned int CDECL _statusfp(void)
 575 {
 576    unsigned int retVal = 0;
 577 #if defined(__GNUC__) && defined(__i386__)
 578   unsigned int fpword;
 579
 580   __asm__ __volatile__( "fstsw %0" : "=m" (fpword) : );
 581   if (fpword & 0x1)  retVal |= MSVCRT__SW_INVALID;
 582   if (fpword & 0x2)  retVal |= MSVCRT__SW_DENORMAL;
 583   if (fpword & 0x4)  retVal |= MSVCRT__SW_ZERODIVIDE;
 584   if (fpword & 0x8)  retVal |= MSVCRT__SW_OVERFLOW;
 585   if (fpword & 0x10) retVal |= MSVCRT__SW_UNDERFLOW;
 586   if (fpword & 0x20) retVal |= MSVCRT__SW_INEXACT;
 587 #else
 588   FIXME(":Not implemented!\n");
 589 #endif
 590   return retVal;
 591 }
 592
 593 /*********************************************************************
 594  *              _clearfp (MSVCRT.@)
 595  */
 596 unsigned int CDECL _clearfp(void)
 597 {
 598   unsigned int retVal = _statusfp();
 599 #if defined(__GNUC__) && defined(__i386__)
 600   __asm__ __volatile__( "fnclex" );
 601 #else
 602   FIXME(":Not Implemented\n");
 603 #endif
 604   return retVal;
 605 }
 606
 607 /*********************************************************************
 608  *              __fpecode (MSVCRT.@)
 609  */
 610 int * CDECL __fpecode(void)
 611 {
 612     return &msvcrt_get_thread_data()->fpecode;
 613 }
 614
 615 /*********************************************************************
 616  *              ldexp (MSVCRT.@)
 617  */
 618 double CDECL MSVCRT_ldexp(double num, long exp)
 619 {
 620   double z = ldexp(num,exp);
 621
 622   if (!finite(z))
 623     *MSVCRT__errno() = MSVCRT_ERANGE;
 624   else if (z == 0 && signbit(z))
 625     z = 0.0; /* Convert -0 -> +0 */
 626   return z;
 627 }
 628
 629 /*********************************************************************
 630  *              _cabs (MSVCRT.@)
 631  */
 632 double CDECL MSVCRT__cabs(struct MSVCRT__complex num)
 633 {
 634   return sqrt(num.x * num.x + num.y * num.y);
 635 }
 636
 637 /*********************************************************************
 638  *              _chgsign (MSVCRT.@)
 639  */
 640 double CDECL _chgsign(double num)
 641 {
 642   /* FIXME: +-infinity,Nan not tested */
 643   return -num;
 644 }
 645
 646 /*********************************************************************
 647  *              _control87 (MSVCRT.@)
 648  */
 649 unsigned int CDECL _control87(unsigned int newval, unsigned int mask)
 650 {
 651 #if defined(__GNUC__) && defined(__i386__)
 652   unsigned int fpword = 0;
 653   unsigned int flags = 0;
 654
 655   TRACE("(%08x, %08x): Called\n", newval, mask);
 656
 657   /* Get fp control word */
 658   __asm__ __volatile__( "fstcw %0" : "=m" (fpword) : );
 659
 660   TRACE("Control word before : %08x\n", fpword);
 661
 662   /* Convert into mask constants */
 663   if (fpword & 0x1)  flags |= MSVCRT__EM_INVALID;
 664   if (fpword & 0x2)  flags |= MSVCRT__EM_DENORMAL;
 665   if (fpword & 0x4)  flags |= MSVCRT__EM_ZERODIVIDE;
 666   if (fpword & 0x8)  flags |= MSVCRT__EM_OVERFLOW;
 667   if (fpword & 0x10) flags |= MSVCRT__EM_UNDERFLOW;
 668   if (fpword & 0x20) flags |= MSVCRT__EM_INEXACT;
 669   switch(fpword & 0xC00) {
 670   case 0xC00: flags |= MSVCRT__RC_UP|MSVCRT__RC_DOWN; break;
 671   case 0x800: flags |= MSVCRT__RC_UP; break;
 672   case 0x400: flags |= MSVCRT__RC_DOWN; break;
 673   }
 674   switch(fpword & 0x300) {
 675   case 0x0:   flags |= MSVCRT__PC_24; break;
 676   case 0x200: flags |= MSVCRT__PC_53; break;
 677   case 0x300: flags |= MSVCRT__PC_64; break;
 678   }
 679   if (fpword & 0x1000) flags |= MSVCRT__IC_AFFINE;
 680
 681   /* Mask with parameters */
 682   flags = (flags & ~mask) | (newval & mask);
 683
 684   /* Convert (masked) value back to fp word */
 685   fpword = 0;
 686   if (flags & MSVCRT__EM_INVALID)    fpword |= 0x1;
 687   if (flags & MSVCRT__EM_DENORMAL)   fpword |= 0x2;
 688   if (flags & MSVCRT__EM_ZERODIVIDE) fpword |= 0x4;
 689   if (flags & MSVCRT__EM_OVERFLOW)   fpword |= 0x8;
 690   if (flags & MSVCRT__EM_UNDERFLOW)  fpword |= 0x10;
 691   if (flags & MSVCRT__EM_INEXACT)    fpword |= 0x20;
 692   switch(flags & (MSVCRT__RC_UP | MSVCRT__RC_DOWN)) {
 693   case MSVCRT__RC_UP|MSVCRT__RC_DOWN: fpword |= 0xC00; break;
 694   case MSVCRT__RC_UP:          fpword |= 0x800; break;
 695   case MSVCRT__RC_DOWN:        fpword |= 0x400; break;
 696   }
 697   switch (flags & (MSVCRT__PC_24 | MSVCRT__PC_53)) {
 698   case MSVCRT__PC_64: fpword |= 0x300; break;
 699   case MSVCRT__PC_53: fpword |= 0x200; break;
 700   case MSVCRT__PC_24: fpword |= 0x0; break;
 701   }
 702   if (flags & MSVCRT__IC_AFFINE) fpword |= 0x1000;
 703
 704   TRACE("Control word after  : %08x\n", fpword);
 705
 706   /* Put fp control word */
 707   __asm__ __volatile__( "fldcw %0" : : "m" (fpword) );
 708
 709   return flags;
 710 #else
 711   FIXME(":Not Implemented!\n");
 712   return 0;
 713 #endif
 714 }
 715
 716 /*********************************************************************
 717  *              _controlfp (MSVCRT.@)
 718  */
 719 unsigned int CDECL _controlfp(unsigned int newval, unsigned int mask)
 720 {
 721 #ifdef __i386__
 722   return _control87( newval, mask & ~MSVCRT__EM_DENORMAL );
 723 #else
 724   FIXME(":Not Implemented!\n");
 725   return 0;
 726 #endif
 727 }
 728
 729 /*********************************************************************
 730  *              _copysign (MSVCRT.@)
 731  */
 732 double CDECL _copysign(double num, double sign)
 733 {
 734   /* FIXME: Behaviour for Nan/Inf? */
 735   if (sign < 0.0)
 736     return num < 0.0 ? num : -num;
 737   return num < 0.0 ? -num : num;
 738 }
 739
 740 /*********************************************************************
 741  *              _finite (MSVCRT.@)
 742  */
 743 int CDECL _finite(double num)
 744 {
 745   return (finite(num)?1:0); /* See comment for _isnan() */
 746 }
 747
 748 /*********************************************************************
 749  *              _fpreset (MSVCRT.@)
 750  */
 751 void CDECL _fpreset(void)
 752 {
 753 #if defined(__GNUC__) && defined(__i386__)
 754   __asm__ __volatile__( "fninit" );
 755 #else
 756   FIXME(":Not Implemented!\n");
 757 #endif
 758 }
 759
 760 /*********************************************************************
 761  *              _isnan (MSVCRT.@)
 762  */
 763 INT CDECL _isnan(double num)
 764 {
 765   /* Some implementations return -1 for true(glibc), msvcrt/crtdll return 1.
 766    * Do the same, as the result may be used in calculations
 767    */
 768   return isnan(num) ? 1 : 0;
 769 }
 770
 771 /*********************************************************************
 772  *              _j0 (MSVCRT.@)
 773  */
 774 double CDECL _j0(double num)
 775 {
 776   /* FIXME: errno handling */
 777   return j0(num);
 778 }
 779
 780 /*********************************************************************
 781  *              _j1 (MSVCRT.@)
 782  */
 783 double CDECL _j1(double num)
 784 {
 785   /* FIXME: errno handling */
 786   return j1(num);
 787 }
 788
 789 /*********************************************************************
 790  *              jn (MSVCRT.@)
 791  */
 792 double CDECL _jn(int n, double num)
 793 {
 794   /* FIXME: errno handling */
 795   return jn(n, num);
 796 }
 797
 798 /*********************************************************************
 799  *              _y0 (MSVCRT.@)
 800  */
 801 double CDECL _y0(double num)
 802 {
 803   double retval;
 804   if (!finite(num)) *MSVCRT__errno() = MSVCRT_EDOM;
 805   retval  = y0(num);
 806   if (_fpclass(retval) == MSVCRT__FPCLASS_NINF)
 807   {
 808     *MSVCRT__errno() = MSVCRT_EDOM;
 809     retval = sqrt(-1);
 810   }
 811   return retval;
 812 }
 813
 814 /*********************************************************************
 815  *              _y1 (MSVCRT.@)
 816  */
 817 double CDECL _y1(double num)
 818 {
 819   double retval;
 820   if (!finite(num)) *MSVCRT__errno() = MSVCRT_EDOM;
 821   retval  = y1(num);
 822   if (_fpclass(retval) == MSVCRT__FPCLASS_NINF)
 823   {
 824     *MSVCRT__errno() = MSVCRT_EDOM;
 825     retval = sqrt(-1);
 826   }
 827   return retval;
 828 }
 829
 830 /*********************************************************************
 831  *              _yn (MSVCRT.@)
 832  */
 833 double CDECL _yn(int order, double num)
 834 {
 835   double retval;
 836   if (!finite(num)) *MSVCRT__errno() = MSVCRT_EDOM;
 837   retval  = yn(order,num);
 838   if (_fpclass(retval) == MSVCRT__FPCLASS_NINF)
 839   {
 840     *MSVCRT__errno() = MSVCRT_EDOM;
 841     retval = sqrt(-1);
 842   }
 843   return retval;
 844 }
 845
 846 /*********************************************************************
 847  *              _nextafter (MSVCRT.@)
 848  */
 849 double CDECL _nextafter(double num, double next)
 850 {
 851   double retval;
 852   if (!finite(num) || !finite(next)) *MSVCRT__errno() = MSVCRT_EDOM;
 853   retval = nextafter(num,next);
 854   return retval;
 855 }
 856
 857 /*********************************************************************
 858  *              _ecvt (MSVCRT.@)
 859  */
 860 char * CDECL _ecvt( double number, int ndigits, int *decpt, int *sign )
 861 {
 862     thread_data_t *data = msvcrt_get_thread_data();
 863     char *dec;
 864
 865     if (!data->efcvt_buffer)
 866         data->efcvt_buffer = MSVCRT_malloc( 80 ); /* ought to be enough */
 867
 868     snprintf(data->efcvt_buffer, 80, "%.*e", ndigits /* FIXME wrong */, number);
 869     *sign = (number < 0);
 870     dec = strchr(data->efcvt_buffer, '.');
 871     *decpt = (dec) ? dec - data->efcvt_buffer : -1;
 872     return data->efcvt_buffer;
 873 }
 874
 875 /***********************************************************************
 876  *              _fcvt  (MSVCRT.@)
 877  */
 878 char * CDECL _fcvt( double number, int ndigits, int *decpt, int *sign )
 879 {
 880     thread_data_t *data = msvcrt_get_thread_data();
 881     int stop, dec1, dec2;
 882     char *ptr1, *ptr2, *first;
 883     char buf[80]; /* ought to be enough */
 884
 885     if (!data->efcvt_buffer)
 886         data->efcvt_buffer = MSVCRT_malloc( 80 ); /* ought to be enough */
 887
 888     if (number < 0)
 889     {
 890         *sign = 1;
 891         number = -number;
 892     } else *sign = 0;
 893
 894     snprintf(buf, 80, "%.*f", ndigits < 0 ? 0 : ndigits, number);
 895     ptr1 = buf;
 896     ptr2 = data->efcvt_buffer;
 897     first = NULL;
 898     dec1 = 0;
 899     dec2 = 0;
 900
 901     /* For numbers below the requested resolution, work out where
 902        the decimal point will be rather than finding it in the string */
 903     if (number < 1.0 && number > 0.0) {
 904         dec2 = log10(number + 1e-10);
 905         if (-dec2 <= ndigits) dec2 = 0;
 906     }
 907
 908     /* If requested digits is zero or less, we will need to truncate
 909      * the returned string */
 910     if (ndigits < 1) {
 911         stop = strlen(buf) + ndigits;
 912     } else {
 913         stop = strlen(buf);
 914     }
 915
 916     while (*ptr1 == '0') ptr1++; /* Skip leading zeroes */
 917     while (*ptr1 != '\0' && *ptr1 != '.') {
 918         if (!first) first = ptr2;
 919         if ((ptr1 - buf) < stop) {
 920             *ptr2++ = *ptr1++;
 921         } else {
 922             ptr1++;
 923         }
 924         dec1++;
 925     }
 926
 927     if (ndigits > 0) {
 928         ptr1++;
 929         if (!first) {
 930             while (*ptr1 == '0') { /* Process leading zeroes */
 931                 *ptr2++ = *ptr1++;
 932                 dec1--;
 933             }
 934         }
 935         while (*ptr1 != '\0') {
 936             if (!first) first = ptr2;
 937             *ptr2++ = *ptr1++;
 938         }
 939     }
 940
 941     *ptr2 = '\0';
 942
 943     /* We never found a non-zero digit, then our number is either
 944      * smaller than the requested precision, or 0.0 */
 945     if (!first) {
 946         if (number > 0.0) {
 947             first = ptr2;
 948         } else {
 949             first = data->efcvt_buffer;
 950             dec1 = 0;
 951         }
 952     }
 953
 954     *decpt = dec2 ? dec2 : dec1;
 955     return first;
 956 }
 957
 958 /***********************************************************************
 959  *              _gcvt  (MSVCRT.@)
 960  *
 961  * FIXME: uses both E and F.
 962  */
 963 char * CDECL _gcvt( double number, int ndigit, char *buff )
 964 {
 965     sprintf(buff, "%.*E", ndigit, number);
 966     return buff;
 967 }
 968
 969 #include <stdlib.h> /* div_t, ldiv_t */
 970
 971 /*********************************************************************
 972  *              div (MSVCRT.@)
 973  * VERSION
 974  *      [i386] Windows binary compatible - returns the struct in eax/edx.
 975  */
 976 #ifdef __i386__
 977 unsigned __int64 CDECL MSVCRT_div(int num, int denom)
 978 {
 979   div_t dt = div(num,denom);
 980   return ((unsigned __int64)dt.rem << 32) | (unsigned int)dt.quot;
 981 }
 982 #else
 983 /*********************************************************************
 984  *              div (MSVCRT.@)
 985  * VERSION
 986  *      [!i386] Non-x86 can't run win32 apps so we don't need binary compatibility
 987  */
 988 MSVCRT_div_t CDECL MSVCRT_div(int num, int denom)
 989 {
 990   div_t dt = div(num,denom);
 991   MSVCRT_div_t     ret;
 992   ret.quot = dt.quot;
 993   ret.rem = dt.rem;
 994
 995   return ret;
 996
 997 }
 998 #endif /* ifdef __i386__ */
 999
1000
1001 /*********************************************************************
1002  *              ldiv (MSVCRT.@)
1003  * VERSION
1004  *      [i386] Windows binary compatible - returns the struct in eax/edx.
1005  */
1006 #ifdef __i386__
1007 unsigned __int64 CDECL MSVCRT_ldiv(long num, long denom)
1008 {
1009   ldiv_t ldt = ldiv(num,denom);
1010   return ((unsigned __int64)ldt.rem << 32) | (unsigned long)ldt.quot;
1011 }
1012 #else
1013 /*********************************************************************
1014  *              ldiv (MSVCRT.@)
1015  * VERSION
1016  *      [!i386] Non-x86 can't run win32 apps so we don't need binary compatibility
1017  */
1018 MSVCRT_ldiv_t CDECL MSVCRT_ldiv(long num, long denom)
1019 {
1020   ldiv_t result = ldiv(num,denom);
1021
1022   MSVCRT_ldiv_t ret;
1023   ret.quot = result.quot;
1024   ret.rem = result.rem;
1025
1026   return ret;
1027 }
1028 #endif /* ifdef __i386__ */
1029
1030 /***********************************************************************
1031  *              _adj_fdiv_m16i (MSVCRT.@)
1032  *
1033  * NOTE
1034  *    I _think_ this function is intended to work around the Pentium
1035  *    fdiv bug.
1036  */
1037 void __stdcall _adj_fdiv_m16i( short arg )
1038 {
1039   TRACE("(): stub\n");
1040 }
1041
1042 /***********************************************************************
1043  *              _adj_fdiv_m32 (MSVCRT.@)
1044  *
1045  * NOTE
1046  *    I _think_ this function is intended to work around the Pentium
1047  *    fdiv bug.
1048  */
1049 void __stdcall _adj_fdiv_m32( unsigned int arg )
1050 {
1051   TRACE("(): stub\n");
1052 }
1053
1054 /***********************************************************************
1055  *              _adj_fdiv_m32i (MSVCRT.@)
1056  *
1057  * NOTE
1058  *    I _think_ this function is intended to work around the Pentium
1059  *    fdiv bug.
1060  */
1061 void __stdcall _adj_fdiv_m32i( int arg )
1062 {
1063   TRACE("(): stub\n");
1064 }
1065
1066 /***********************************************************************
1067  *              _adj_fdiv_m64 (MSVCRT.@)
1068  *
1069  * NOTE
1070  *    I _think_ this function is intended to work around the Pentium
1071  *    fdiv bug.
1072  */
1073 void __stdcall _adj_fdiv_m64( unsigned __int64 arg )
1074 {
1075   TRACE("(): stub\n");
1076 }
1077
1078 /***********************************************************************
1079  *              _adj_fdiv_r (MSVCRT.@)
1080  * FIXME
1081  *    This function is likely to have the wrong number of arguments.
1082  *
1083  * NOTE
1084  *    I _think_ this function is intended to work around the Pentium
1085  *    fdiv bug.
1086  */
1087 void _adj_fdiv_r(void)
1088 {
1089   TRACE("(): stub\n");
1090 }
1091
1092 /***********************************************************************
1093  *              _adj_fdivr_m16i (MSVCRT.@)
1094  *
1095  * NOTE
1096  *    I _think_ this function is intended to work around the Pentium
1097  *    fdiv bug.
1098  */
1099 void __stdcall _adj_fdivr_m16i( short arg )
1100 {
1101   TRACE("(): stub\n");
1102 }
1103
1104 /***********************************************************************
1105  *              _adj_fdivr_m32 (MSVCRT.@)
1106  *
1107  * NOTE
1108  *    I _think_ this function is intended to work around the Pentium
1109  *    fdiv bug.
1110  */
1111 void __stdcall _adj_fdivr_m32( unsigned int arg )
1112 {
1113   TRACE("(): stub\n");
1114 }
1115
1116 /***********************************************************************
1117  *              _adj_fdivr_m32i (MSVCRT.@)
1118  *
1119  * NOTE
1120  *    I _think_ this function is intended to work around the Pentium
1121  *    fdiv bug.
1122  */
1123 void __stdcall _adj_fdivr_m32i( int arg )
1124 {
1125   TRACE("(): stub\n");
1126 }
1127
1128 /***********************************************************************
1129  *              _adj_fdivr_m64 (MSVCRT.@)
1130  *
1131  * NOTE
1132  *    I _think_ this function is intended to work around the Pentium
1133  *    fdiv bug.
1134  */
1135 void __stdcall _adj_fdivr_m64( unsigned __int64 arg )
1136 {
1137   TRACE("(): stub\n");
1138 }
1139
1140 /***********************************************************************
1141  *              _adj_fpatan (MSVCRT.@)
1142  * FIXME
1143  *    This function is likely to have the wrong number of arguments.
1144  *
1145  * NOTE
1146  *    I _think_ this function is intended to work around the Pentium
1147  *    fdiv bug.
1148  */
1149 void _adj_fpatan(void)
1150 {
1151   TRACE("(): stub\n");
1152 }
1153
1154 /***********************************************************************
1155  *              _adj_fprem (MSVCRT.@)
1156  * FIXME
1157  *    This function is likely to have the wrong number of arguments.
1158  *
1159  * NOTE
1160  *    I _think_ this function is intended to work around the Pentium
1161  *    fdiv bug.
1162  */
1163 void _adj_fprem(void)
1164 {
1165   TRACE("(): stub\n");
1166 }
1167
1168 /***********************************************************************
1169  *              _adj_fprem1 (MSVCRT.@)
1170  * FIXME
1171  *    This function is likely to have the wrong number of arguments.
1172  *
1173  * NOTE
1174  *    I _think_ this function is intended to work around the Pentium
1175  *    fdiv bug.
1176  */
1177 void _adj_fprem1(void)
1178 {
1179   TRACE("(): stub\n");
1180 }
1181
1182 /***********************************************************************
1183  *              _adj_fptan (MSVCRT.@)
1184  * FIXME
1185  *    This function is likely to have the wrong number of arguments.
1186  *
1187  * NOTE
1188  *    I _think_ this function is intended to work around the Pentium
1189  *    fdiv bug.
1190  */
1191 void _adj_fptan(void)
1192 {
1193   TRACE("(): stub\n");
1194 }
1195
1196 /***********************************************************************
1197  *              _adjust_fdiv (MSVCRT.@)
1198  * FIXME
1199  *    I _think_ this function should be a variable indicating whether
1200  *    Pentium fdiv bug safe code should be used.
1201  */
1202 void _adjust_fdiv(void)
1203 {
1204   TRACE("(): stub\n");
1205 }
1206
1207 /***********************************************************************
1208  *              _safe_fdiv (MSVCRT.@)
1209  * FIXME
1210  *    This function is likely to have the wrong number of arguments.
1211  *
1212  * NOTE
1213  *    I _think_ this function is intended to work around the Pentium
1214  *    fdiv bug.
1215  */
1216 void _safe_fdiv(void)
1217 {
1218   TRACE("(): stub\n");
1219 }
1220
1221 /***********************************************************************
1222  *              _safe_fdivr (MSVCRT.@)
1223  * FIXME
1224  *    This function is likely to have the wrong number of arguments.
1225  *
1226  * NOTE
1227  *    I _think_ this function is intended to work around the Pentium
1228  *    fdiv bug.
1229  */
1230 void _safe_fdivr(void)
1231 {
1232   TRACE("(): stub\n");
1233 }
1234
1235 /***********************************************************************
1236  *              _safe_fprem (MSVCRT.@)
1237  * FIXME
1238  *    This function is likely to have the wrong number of arguments.
1239  *
1240  * NOTE
1241  *    I _think_ this function is intended to work around the Pentium
1242  *    fdiv bug.
1243  */
1244 void _safe_fprem(void)
1245 {
1246   TRACE("(): stub\n");
1247 }
1248
1249 /***********************************************************************
1250  *              _safe_fprem1 (MSVCRT.@)
1251  *
1252  * FIXME
1253  *    This function is likely to have the wrong number of arguments.
1254  *
1255  * NOTE
1256  *    I _think_ this function is intended to work around the Pentium
1257  *    fdiv bug.
1258  */
1259 void _safe_fprem1(void)
1260 {
1261   TRACE("(): stub\n");
1262 }