1 /* Copyright (C) 1998, 1999, 2000 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3 Contributed by Richard Henderson.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Library General Public License as
7 published by the Free Software Foundation; either version 2 of the
8 License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Library General Public License for more details.
15 You should have received a copy of the GNU Library General Public
16 License along with the GNU C Library; see the file COPYING.LIB. If not,
17 write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA. */
23 /* Use the -inf rounding mode conversion instructions to implement
24 floor. We note when the exponent is large enough that the value
25 must be integral, as this avoids unpleasant integer overflows. */
30 if (isless (fabsf (x
), 16777216.0f
)) /* 1 << FLT_MANT_DIG */
32 /* Note that Alpha S_Floating is stored in registers in a
33 restricted T_Floating format, so we don't even need to
34 convert back to S_Floating in the end. The initial
35 conversion to T_Floating is needed to handle denormals. */
37 float tmp1
, tmp2
, new_x
;
39 __asm ("cvtst/s %3,%2\n\t"
40 #ifdef _IEEE_FP_INEXACT
41 "cvttq/svim %2,%1\n\t"
46 : "=f"(new_x
), "=&f"(tmp1
), "=&f"(tmp2
)
49 /* floor(-0) == -0, and in general we'll always have the same
51 x
= copysignf(new_x
, x
);
56 weak_alias (__floorf
, floorf
)