| /* |
| * ==================================================== |
| * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. |
| * |
| * Developed at SunPro, a Sun Microsystems, Inc. business. |
| * Permission to use, copy, modify, and distribute this |
| * software is freely granted, provided that this notice |
| * is preserved. |
| * ==================================================== |
| */ |
| |
| #include "fdlibm.h" |
| |
| #ifdef __STDC__ |
| float truncf(float x) |
| #else |
| float truncf(x) |
| float x; |
| #endif |
| { |
| __int32_t signbit, w, exponent_less_127; |
| |
| GET_FLOAT_WORD(w,x); |
| |
| /* Extract sign bit. */ |
| signbit = w & 0x80000000; |
| |
| /* Extract exponent field. */ |
| exponent_less_127 = ((w & 0x7f800000) >> 23) - 127; |
| |
| if (exponent_less_127 < 23) |
| { |
| if (exponent_less_127 < 0) |
| { |
| /* -1 < x < 1, so result is +0 or -0. */ |
| SET_FLOAT_WORD(x, signbit); |
| } |
| else |
| { |
| SET_FLOAT_WORD(x, signbit | (w & ~(0x007fffff >> exponent_less_127))); |
| } |
| } |
| else |
| { |
| if (exponent_less_127 == 255) |
| /* x is NaN or infinite. */ |
| return x + x; |
| |
| /* All bits in the fraction field are relevant. */ |
| } |
| return x; |
| } |
| |
| #ifdef _DOUBLE_IS_32BITS |
| |
| #ifdef __STDC__ |
| double trunc(double x) |
| #else |
| double trunc(x) |
| double x; |
| #endif |
| { |
| return (double) truncf((float) x); |
| } |
| |
| #endif /* defined(_DOUBLE_IS_32BITS) */ |