int ilogbf(float x)
{
- union fshape u = {x};
- int e = u.bits>>23 & 0xff;
+ #pragma STDC FENV_ACCESS ON
+ union {float f; uint32_t i;} u = {x};
+ uint32_t i = u.i;
+ int e = i>>23 & 0xff;
if (!e) {
- u.bits <<= 9;
- if (u.bits == 0) {
+ i <<= 9;
+ if (i == 0) {
FORCE_EVAL(0/0.0f);
return FP_ILOGB0;
}
/* subnormal x */
- for (e = -0x7f; u.bits < (uint32_t)1<<31; e--, u.bits<<=1);
+ for (e = -0x7f; i>>31 == 0; e--, i<<=1);
return e;
}
if (e == 0xff) {
FORCE_EVAL(0/0.0f);
- return u.bits<<9 ? FP_ILOGBNAN : INT_MAX;
+ return i<<9 ? FP_ILOGBNAN : INT_MAX;
}
return e - 0x7f;
}