1 #include "libm.h" 2 floorf(float x)3float floorf(float x) 4 { 5 union {float f; uint32_t i;} u = {x}; 6 int e = (int)(u.i >> 23 & 0xff) - 0x7f; 7 uint32_t m; 8 9 if (e >= 23) 10 return x; 11 if (e >= 0) { 12 m = 0x007fffff >> e; 13 if ((u.i & m) == 0) 14 return x; 15 FORCE_EVAL(x + 0x1p120f); 16 if (u.i >> 31) 17 u.i += m; 18 u.i &= ~m; 19 } else { 20 FORCE_EVAL(x + 0x1p120f); 21 if (u.i >> 31 == 0) 22 u.i = 0; 23 else if (u.i << 1) 24 u.f = -1.0; 25 } 26 return u.f; 27 } 28