diff options
Diffstat (limited to 'src')
-rw-r--r-- | src/math/modf.c | 89 | ||||
-rw-r--r-- | src/math/modff.c | 28 |
2 files changed, 45 insertions, 72 deletions
diff --git a/src/math/modf.c b/src/math/modf.c index cca3b652..de45069f 100644 --- a/src/math/modf.c +++ b/src/math/modf.c @@ -1,68 +1,37 @@ -/* origin: FreeBSD /usr/src/lib/msun/src/s_modf.c */ -/* - * ==================================================== - * 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. - * ==================================================== - */ -/* - * modf(double x, double *iptr) - * return fraction part of x, and return x's integral part in *iptr. - * Method: - * Bit twiddling. - * - * Exception: - * No exception. - */ - -#include "libm.h" +#include <math.h> +#include <stdint.h> double modf(double x, double *iptr) { - int32_t i0,i1,j0; - uint32_t i; + union {double x; uint64_t n;} u = {x}; + uint64_t mask; + int e; - EXTRACT_WORDS(i0, i1, x); - j0 = ((i0>>20) & 0x7ff) - 0x3ff; /* exponent of x */ - if (j0 < 20) { /* integer part in high x */ - if (j0 < 0) { /* |x| < 1 */ - INSERT_WORDS(*iptr, i0 & 0x80000000, 0); /* *iptr = +-0 */ - return x; - } - i = 0x000fffff >> j0; - if (((i0&i)|i1) == 0) { /* x is integral */ - uint32_t high; - *iptr = x; - GET_HIGH_WORD(high, x); - INSERT_WORDS(x, high & 0x80000000, 0); /* return +-0 */ - return x; - } - INSERT_WORDS(*iptr, i0&~i, 0); - return x - *iptr; - } else if (j0 > 51) { /* no fraction part */ - uint32_t high; - if (j0 == 0x400) { /* inf/NaN */ - *iptr = x; - return 0.0 / x; - } + e = (int)(u.n>>52 & 0x7ff) - 0x3ff; + + /* no fractional part */ + if (e >= 52) { *iptr = x; - GET_HIGH_WORD(high, x); - INSERT_WORDS(x, high & 0x80000000, 0); /* return +-0 */ - return x; - } else { /* fraction part in low x */ - i = (uint32_t)0xffffffff >> (j0 - 20); - if ((i1&i) == 0) { /* x is integral */ - uint32_t high; - *iptr = x; - GET_HIGH_WORD(high, x); - INSERT_WORDS(x, high & 0x80000000, 0); /* return +-0 */ + if (e == 0x400 && u.n<<12 != 0) /* nan */ return x; - } - INSERT_WORDS(*iptr, i0, i1&~i); - return x - *iptr; + u.n &= (uint64_t)1<<63; + return u.x; + } + + /* no integral part*/ + if (e < 0) { + u.n &= (uint64_t)1<<63; + *iptr = u.x; + return x; + } + + mask = (uint64_t)-1>>12 >> e; + if ((u.n & mask) == 0) { + *iptr = x; + u.n &= (uint64_t)1<<63; + return u.x; } + u.n &= ~mask; + *iptr = u.x; + return x - *iptr; } diff --git a/src/math/modff.c b/src/math/modff.c index bf6e4ced..84d0b82a 100644 --- a/src/math/modff.c +++ b/src/math/modff.c @@ -1,33 +1,37 @@ -#include "libm.h" +#include <math.h> +#include <stdint.h> float modff(float x, float *iptr) { - uint32_t u, mask; + union {float x; uint32_t n;} u = {x}; + uint32_t mask; int e; - GET_FLOAT_WORD(u, x); - e = (int)(u>>23 & 0xff) - 0x7f; + e = (int)(u.n>>23 & 0xff) - 0x7f; /* no fractional part */ if (e >= 23) { *iptr = x; - if (e == 0x80 && u<<9 != 0) /* nan */ + if (e == 0x80 && u.n<<9 != 0) { /* nan */ return x; - SET_FLOAT_WORD(x, u & 0x80000000); - return x; + } + u.n &= 0x80000000; + return u.x; } /* no integral part */ if (e < 0) { - SET_FLOAT_WORD(*iptr, u & 0x80000000); + u.n &= 0x80000000; + *iptr = u.x; return x; } mask = 0x007fffff>>e; - if ((u & mask) == 0) { + if ((u.n & mask) == 0) { *iptr = x; - SET_FLOAT_WORD(x, u & 0x80000000); - return x; + u.n &= 0x80000000; + return u.x; } - SET_FLOAT_WORD(*iptr, u & ~mask); + u.n &= ~mask; + *iptr = u.x; return x - *iptr; } |