diff options
Diffstat (limited to 'lib/libc/gen')
| -rw-r--r-- | lib/libc/gen/Makefile.inc | 2 | ||||
| -rw-r--r-- | lib/libc/gen/Symbol.map | 1 | ||||
| -rw-r--r-- | lib/libc/gen/modf.c | 138 |
3 files changed, 141 insertions, 0 deletions
diff --git a/lib/libc/gen/Makefile.inc b/lib/libc/gen/Makefile.inc index d55bc46..d3ccf0a 100644 --- a/lib/libc/gen/Makefile.inc +++ b/lib/libc/gen/Makefile.inc @@ -35,6 +35,8 @@ SRCS+= __getosreldate.c __xuname.c \ usleep.c utime.c utxdb.c valloc.c vis.c wait.c wait3.c waitpid.c \ wordexp.c +MISRCS+=modf.c + CANCELPOINTS_SRCS=sem.c sem_new.c .for src in ${CANCELPOINTS_SRCS} SRCS+=cancelpoints_${src} diff --git a/lib/libc/gen/Symbol.map b/lib/libc/gen/Symbol.map index 32cf92c..c62e016 100644 --- a/lib/libc/gen/Symbol.map +++ b/lib/libc/gen/Symbol.map @@ -213,6 +213,7 @@ FBSD_1.0 { ldexp; lockf; lrand48; + modf; mrand48; nftw; nice; diff --git a/lib/libc/gen/modf.c b/lib/libc/gen/modf.c new file mode 100644 index 0000000..d67b441 --- /dev/null +++ b/lib/libc/gen/modf.c @@ -0,0 +1,138 @@ +/* @(#)s_modf.c 5.1 93/09/24 */ +/* + * ==================================================== + * 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 <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +/* + * 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 <sys/types.h> +#include <machine/endian.h> +#include <math.h> + +/* Bit fiddling routines copied from msun/src/math_private.h,v 1.15 */ + +#if BYTE_ORDER == BIG_ENDIAN + +typedef union +{ + double value; + struct + { + u_int32_t msw; + u_int32_t lsw; + } parts; +} ieee_double_shape_type; + +#endif + +#if BYTE_ORDER == LITTLE_ENDIAN + +typedef union +{ + double value; + struct + { + u_int32_t lsw; + u_int32_t msw; + } parts; +} ieee_double_shape_type; + +#endif + +/* Get two 32 bit ints from a double. */ + +#define EXTRACT_WORDS(ix0,ix1,d) \ +do { \ + ieee_double_shape_type ew_u; \ + ew_u.value = (d); \ + (ix0) = ew_u.parts.msw; \ + (ix1) = ew_u.parts.lsw; \ +} while (0) + +/* Get the more significant 32 bit int from a double. */ + +#define GET_HIGH_WORD(i,d) \ +do { \ + ieee_double_shape_type gh_u; \ + gh_u.value = (d); \ + (i) = gh_u.parts.msw; \ +} while (0) + +/* Set a double from two 32 bit ints. */ + +#define INSERT_WORDS(d,ix0,ix1) \ +do { \ + ieee_double_shape_type iw_u; \ + iw_u.parts.msw = (ix0); \ + iw_u.parts.lsw = (ix1); \ + (d) = iw_u.value; \ +} while (0) + +static const double one = 1.0; + +double +modf(double x, double *iptr) +{ + int32_t i0,i1,j0; + u_int32_t i; + 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; + } else { + i = (0x000fffff)>>j0; + if(((i0&i)|i1)==0) { /* x is integral */ + u_int32_t high; + *iptr = x; + GET_HIGH_WORD(high,x); + INSERT_WORDS(x,high&0x80000000,0); /* return +-0 */ + return x; + } else { + INSERT_WORDS(*iptr,i0&(~i),0); + return x - *iptr; + } + } + } else if (j0>51) { /* no fraction part */ + u_int32_t high; + if (j0 == 0x400) { /* inf/NaN */ + *iptr = x; + return 0.0 / x; + } + *iptr = x*one; + GET_HIGH_WORD(high,x); + INSERT_WORDS(x,high&0x80000000,0); /* return +-0 */ + return x; + } else { /* fraction part in low x */ + i = ((u_int32_t)(0xffffffff))>>(j0-20); + if((i1&i)==0) { /* x is integral */ + u_int32_t high; + *iptr = x; + GET_HIGH_WORD(high,x); + INSERT_WORDS(x,high&0x80000000,0); /* return +-0 */ + return x; + } else { + INSERT_WORDS(*iptr,i0,i1&(~i)); + return x - *iptr; + } + } +} |
