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Diffstat (limited to 'src/math/rintf.c')
-rw-r--r-- | src/math/rintf.c | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/src/math/rintf.c b/src/math/rintf.c new file mode 100644 index 00000000..e8d44969 --- /dev/null +++ b/src/math/rintf.c @@ -0,0 +1,48 @@ +/* origin: FreeBSD /usr/src/lib/msun/src/s_rintf.c */ +/* + * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. + */ +/* + * ==================================================== + * 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 "libm.h" + +static const float +TWO23[2] = { + 8.3886080000e+06, /* 0x4b000000 */ + -8.3886080000e+06, /* 0xcb000000 */ +}; + +float rintf(float x) +{ + int32_t i0,j0,sx; + float w,t; + + GET_FLOAT_WORD(i0, x); + sx = (i0>>31) & 1; + j0 = ((i0>>23)&0xff) - 0x7f; + if (j0 < 23) { + if (j0 < 0) { + if ((i0&0x7fffffff) == 0) + return x; + STRICT_ASSIGN(float, w, TWO23[sx] + x); + t = w - TWO23[sx]; + GET_FLOAT_WORD(i0, t); + SET_FLOAT_WORD(t, (i0&0x7fffffff)|(sx<<31)); + return t; + } + STRICT_ASSIGN(float, w, TWO23[sx] + x); + return w - TWO23[sx]; + } + if (j0 == 0x80) + return x+x; /* inf or NaN */ + return x; /* x is integral */ +} |