contrib/compiler-rt/lib/builtins/ppc/divtc3.c

   1 /* This file is distributed under the University of Illinois Open Source
   2  * License. See LICENSE.TXT for details.
   3  */
   4
   5 #include "DD.h"
   6 #include "../int_math.h"
   7
   8 #if !defined(CRT_INFINITY) && defined(HUGE_VAL)
   9 #define CRT_INFINITY HUGE_VAL
  10 #endif /* CRT_INFINITY */
  11
  12 #define makeFinite(x) { \
  13     (x).s.hi = crt_copysign(crt_isinf((x).s.hi) ? 1.0 : 0.0, (x).s.hi); \
  14     (x).s.lo = 0.0;                                                     \
  15   }
  16
  17 long double _Complex
  18 __divtc3(long double a, long double b, long double c, long double d)
  19 {
  20         DD cDD = { .ld = c };
  21         DD dDD = { .ld = d };
  22
  23         int ilogbw = 0;
  24         const double logbw = crt_logb(crt_fmax(crt_fabs(cDD.s.hi), crt_fabs(dDD.s.hi) ));
  25
  26         if (crt_isfinite(logbw))
  27         {
  28                 ilogbw = (int)logbw;
  29
  30                 cDD.s.hi = crt_scalbn(cDD.s.hi, -ilogbw);
  31                 cDD.s.lo = crt_scalbn(cDD.s.lo, -ilogbw);
  32                 dDD.s.hi = crt_scalbn(dDD.s.hi, -ilogbw);
  33                 dDD.s.lo = crt_scalbn(dDD.s.lo, -ilogbw);
  34         }
  35
  36         const long double denom = __gcc_qadd(__gcc_qmul(cDD.ld, cDD.ld), __gcc_qmul(dDD.ld, dDD.ld));
  37         const long double realNumerator = __gcc_qadd(__gcc_qmul(a,cDD.ld), __gcc_qmul(b,dDD.ld));
  38         const long double imagNumerator = __gcc_qsub(__gcc_qmul(b,cDD.ld), __gcc_qmul(a,dDD.ld));
  39
  40         DD real = { .ld = __gcc_qdiv(realNumerator, denom) };
  41         DD imag = { .ld = __gcc_qdiv(imagNumerator, denom) };
  42
  43         real.s.hi = crt_scalbn(real.s.hi, -ilogbw);
  44         real.s.lo = crt_scalbn(real.s.lo, -ilogbw);
  45         imag.s.hi = crt_scalbn(imag.s.hi, -ilogbw);
  46         imag.s.lo = crt_scalbn(imag.s.lo, -ilogbw);
  47
  48         if (crt_isnan(real.s.hi) && crt_isnan(imag.s.hi))
  49         {
  50                 DD aDD = { .ld = a };
  51                 DD bDD = { .ld = b };
  52                 DD rDD = { .ld = denom };
  53
  54                 if ((rDD.s.hi == 0.0) && (!crt_isnan(aDD.s.hi) ||
  55                                           !crt_isnan(bDD.s.hi)))
  56                 {
  57                         real.s.hi = crt_copysign(CRT_INFINITY,cDD.s.hi) * aDD.s.hi;
  58                         real.s.lo = 0.0;
  59                         imag.s.hi = crt_copysign(CRT_INFINITY,cDD.s.hi) * bDD.s.hi;
  60                         imag.s.lo = 0.0;
  61                 }
  62
  63                 else if ((crt_isinf(aDD.s.hi) || crt_isinf(bDD.s.hi)) &&
  64                          crt_isfinite(cDD.s.hi) && crt_isfinite(dDD.s.hi))
  65                 {
  66                         makeFinite(aDD);
  67                         makeFinite(bDD);
  68                         real.s.hi = CRT_INFINITY * (aDD.s.hi*cDD.s.hi + bDD.s.hi*dDD.s.hi);
  69                         real.s.lo = 0.0;
  70                         imag.s.hi = CRT_INFINITY * (bDD.s.hi*cDD.s.hi - aDD.s.hi*dDD.s.hi);
  71                         imag.s.lo = 0.0;
  72                 }
  73
  74                 else if ((crt_isinf(cDD.s.hi) || crt_isinf(dDD.s.hi)) &&
  75                          crt_isfinite(aDD.s.hi) && crt_isfinite(bDD.s.hi))
  76                 {
  77                         makeFinite(cDD);
  78                         makeFinite(dDD);
  79                         real.s.hi = crt_copysign(0.0,(aDD.s.hi*cDD.s.hi + bDD.s.hi*dDD.s.hi));
  80                         real.s.lo = 0.0;
  81                         imag.s.hi = crt_copysign(0.0,(bDD.s.hi*cDD.s.hi - aDD.s.hi*dDD.s.hi));
  82                         imag.s.lo = 0.0;
  83                 }
  84         }
  85
  86         long double _Complex z;
  87         __real__ z = real.ld;
  88         __imag__ z = imag.ld;
  89
  90         return z;
  91 }