From 8334b87bcb31180c70a40ee78e549840fd2d9c0a Mon Sep 17 00:00:00 2001 From: Mike Frysinger Date: Tue, 3 Apr 2007 01:03:42 +0000 Subject: import llrint() from glibc --- libm/Makefile.in | 2 +- libm/s_llrint.c | 93 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 94 insertions(+), 1 deletion(-) create mode 100644 libm/s_llrint.c (limited to 'libm') diff --git a/libm/Makefile.in b/libm/Makefile.in index 2122fabc4..d4fa790f9 100644 --- a/libm/Makefile.in +++ b/libm/Makefile.in @@ -72,7 +72,7 @@ libm_CSRC := \ w_cosh.c w_drem.c w_exp.c w_fmod.c w_gamma.c w_gamma_r.c \ w_hypot.c w_j0.c w_j1.c w_jn.c w_lgamma.c w_lgamma_r.c \ w_log.c w_log10.c w_pow.c w_remainder.c w_scalb.c w_sinh.c \ - w_sqrt.c fpmacros.c nan.c carg.c + w_sqrt.c fpmacros.c nan.c carg.c s_llrint.c FL_MOBJ := \ acosf.o acoshf.o asinf.o asinhf.o atan2f.o atanf.o atanhf.o cbrtf.o \ ceilf.o copysignf.o cosf.o coshf.o erfcf.o erff.o exp2f.o expf.o \ diff --git a/libm/s_llrint.c b/libm/s_llrint.c new file mode 100644 index 000000000..64c870eaa --- /dev/null +++ b/libm/s_llrint.c @@ -0,0 +1,93 @@ +/* Round argument to nearest integral value according to current rounding + direction. + Copyright (C) 1997, 2004, 2006 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Ulrich Drepper , 1997. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include + +#include "math_private.h" + +static const double two52[2] = +{ + 4.50359962737049600000e+15, /* 0x43300000, 0x00000000 */ + -4.50359962737049600000e+15, /* 0xC3300000, 0x00000000 */ +}; + + +long long int +__llrint (double x) +{ + int32_t j0; + u_int32_t i1, i0; + long long int result; + volatile double w; + double t; + int sx; + + EXTRACT_WORDS (i0, i1, x); + j0 = ((i0 >> 20) & 0x7ff) - 0x3ff; + sx = i0 >> 31; + i0 &= 0xfffff; + i0 |= 0x100000; + + if (j0 < 20) + { + w = two52[sx] + x; + t = w - two52[sx]; + EXTRACT_WORDS (i0, i1, t); + j0 = ((i0 >> 20) & 0x7ff) - 0x3ff; + i0 &= 0xfffff; + i0 |= 0x100000; + + result = (j0 < 0 ? 0 : i0 >> (20 - j0)); + } + else if (j0 < (int32_t) (8 * sizeof (long long int)) - 1) + { + if (j0 >= 52) + result = (((long long int) i0 << 32) | i1) << (j0 - 52); + else + { + w = two52[sx] + x; + t = w - two52[sx]; + EXTRACT_WORDS (i0, i1, t); + j0 = ((i0 >> 20) & 0x7ff) - 0x3ff; + i0 &= 0xfffff; + i0 |= 0x100000; + + if (j0 == 20) + result = (long long int) i0; + else + result = ((long long int) i0 << (j0 - 20)) | (i1 >> (52 - j0)); + } + } + else + { + /* The number is too large. It is left implementation defined + what happens. */ + return (long long int) x; + } + + return sx ? -result : result; +} + +weak_alias (__llrint, llrint) +#ifdef NO_LONG_DOUBLE +strong_alias (__llrint, __llrintl) +weak_alias (__llrint, llrintl) +#endif -- cgit v1.2.3