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Diffstat (limited to 'sysdeps/powerpc/q_qtou.c')
-rw-r--r-- | sysdeps/powerpc/q_qtou.c | 64 |
1 files changed, 64 insertions, 0 deletions
diff --git a/sysdeps/powerpc/q_qtou.c b/sysdeps/powerpc/q_qtou.c new file mode 100644 index 0000000000..a5583cc816 --- /dev/null +++ b/sysdeps/powerpc/q_qtou.c @@ -0,0 +1,64 @@ +/* 128-bit floating point to 32-bit fixed point unsigned integer. + Copyright (C) 1997 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Library General Public License as + published by the Free Software Foundation; either version 2 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 + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public + License along with the GNU C Library; see the file COPYING.LIB. If not, + write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, + Boston, MA 02111-1307, USA. */ + +#include <quad_float.h> + +/* unsigned int _q_qtou(const long double *a); + Convert 'a' to unsigned int by truncation. + + Special cases: + -0: return 0 + NaN: raise VXCVI, return 0 + SNaN: raise VXSNAN, VXCVI, and return 0 + Negative numbers (other than -0, but including -Inf): raise VXCVI, return 0 + >= 2^32: raise VXCVI, return 0xffffffff + */ + +unsigned int +__q_qtou(const unsigned long long a[2]) +{ + int ax; + unsigned result; + unsigned long long a0; + + /* Deal with non-special cases. */ + a0 = a[0]; + ax = (a0 >> 48) - 16383; + if (ax <= 31) + /* If we had a '>>' operator that behaved properly with respect to + large shifts, we wouldn't need the '& -(ax >> 31)' term, which + clears 'result' if ax is negative. */ + return (unsigned)(a0 >> 17 | 0x80000000) >> 31-ax & -(ax >> 31); + + /* 'result' is 1 if a is negative, 0 otherwise. */ + result = a0 >> 63; + /* Check for -0, otherwise raise VXCVI. */ + if (a0 != 0x8000000000000000ULL || a[1] != 0) + { + /* Check for SNaN, if so raise VXSNAN. */ + if ((a0 >> 32 & 0x7fff8000) == 0x7fff0000 + && (a[1] | a0 & 0x00007fffffffffffULL) != 0) + set_fpscr_bit(FPSCR_VXSNAN); + /* Treat all NaNs as large negative numbers. */ + result |= cntlzw(~(a0 >> 32) & 0x7fff0000) >> 5; + + set_fpscr_bit(FPSCR_VXCVI); + } + return result-1; +} |