| /* ceil function, sparc64 version. |
| Copyright (C) 2012-2014 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| Contributed by David S. Miller <davem@davemloft.net>, 2012. |
| |
| 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, see |
| <http://www.gnu.org/licenses/>. */ |
| |
| #include <sysdep.h> |
| |
| /* Since changing the rounding mode is extremely expensive, we |
| try to round up using a method that is rounding mode |
| agnostic. |
| |
| We add then subtract (or subtract than add if the initial |
| value was negative) 2**23 to the value, then subtract it |
| back out. |
| |
| This will clear out the fractional portion of the value. |
| One of two things will happen for non-whole initial values. |
| Either the rounding mode will round it up, or it will be |
| rounded down. If the value started out whole, it will be |
| equal after the addition and subtraction. This means we |
| can accurately detect with one test whether we need to add |
| another 1.0 to round it up properly. |
| |
| We pop constants into the FPU registers using the incoming |
| argument stack slots, since this avoid having to use any |
| PIC references. We also thus avoid having to allocate a |
| register window. |
| |
| VIS instructions are used to facilitate the formation of |
| easier constants, and the propagation of the sign bit. */ |
| |
| #define TWO_FIFTYTWO 0x43300000 /* 2**52 */ |
| #define ONE_DOT_ZERO 0x3ff00000 /* 1.0 */ |
| |
| #define ZERO %f10 /* 0.0 */ |
| #define SIGN_BIT %f12 /* -0.0 */ |
| |
| ENTRY (__ceil) |
| sethi %hi(TWO_FIFTYTWO), %o2 |
| sethi %hi(ONE_DOT_ZERO), %o3 |
| fzero ZERO |
| |
| sllx %o2, 32, %o2 |
| fnegd ZERO, SIGN_BIT |
| |
| sllx %o3, 32, %o3 |
| stx %o2, [%sp + STACK_BIAS + 128] |
| fabsd %f0, %f14 |
| |
| ldd [%sp + STACK_BIAS + 128], %f16 |
| fcmpd %fcc3, %f14, %f16 |
| |
| fmovduge %fcc3, ZERO, %f16 |
| fand %f0, SIGN_BIT, SIGN_BIT |
| |
| for %f16, SIGN_BIT, %f16 |
| faddd %f0, %f16, %f18 |
| fsubd %f18, %f16, %f18 |
| fcmpd %fcc2, %f18, %f0 |
| stx %o3, [%sp + STACK_BIAS + 128] |
| |
| ldd [%sp + STACK_BIAS + 128], %f20 |
| fmovduge %fcc2, ZERO, %f20 |
| faddd %f18, %f20, %f0 |
| fabsd %f0, %f0 |
| retl |
| for %f0, SIGN_BIT, %f0 |
| END (__ceil) |
| weak_alias (__ceil, ceil) |