nsz Git - musl/blob - src/math/scalbnf.c

   1 #include "libm.h"
   2
   3 float scalbnf(float x, int n)
   4 {
   5         float scale;
   6
   7         if (n > 127) {
   8                 x *= 0x1p127f;
   9                 n -= 127;
  10                 if (n > 127) {
  11                         x *= 0x1p127f;
  12                         n -= 127;
  13                         if (n > 127)
  14                                 return x * 0x1p127f;
  15                 }
  16         } else if (n < -126) {
  17                 x *= 0x1p-126f;
  18                 n += 126;
  19                 if (n < -126) {
  20                         x *= 0x1p-126f;
  21                         n += 126;
  22                         if (n < -126)
  23                                 return x * 0x1p-126f;
  24                 }
  25         }
  26         SET_FLOAT_WORD(scale, (uint32_t)(0x7f+n)<<23);
  27         return x * scale;
  28 }