| 1 | /* lround() - S390 version. |
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| 2 | Copyright (C) 2019-2024 Free Software Foundation, Inc. |
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| 3 | |
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| 4 | This file is part of the GNU C Library. |
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| 5 | |
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| 6 | The GNU C Library is free software; you can redistribute it and/or |
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| 7 | modify it under the terms of the GNU Lesser General Public License as |
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| 8 | published by the Free Software Foundation; either version 2.1 of the |
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| 9 | License, or (at your option) any later version. |
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| 10 | |
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| 11 | The GNU C Library is distributed in the hope that it will be useful, |
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| 12 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
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| 13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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| 14 | Lesser General Public License for more details. |
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| 15 | |
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| 16 | You should have received a copy of the GNU Lesser General Public |
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| 17 | License along with the GNU C Library; if not, see |
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| 18 | <https://www.gnu.org/licenses/>. */ |
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| 19 | |
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| 20 | #ifdef HAVE_S390_MIN_Z196_ZARCH_ASM_SUPPORT |
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| 21 | # include <math.h> |
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| 22 | # include <libm-alias-double.h> |
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| 23 | |
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| 24 | /* The sizeof (long int) differs between s390x (8byte) and s390 (4byte). |
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| 25 | Thus we need different instructions as the target size is encoded there. |
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| 26 | Note: On s390 this instruction is only used if build with -mzarch. */ |
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| 27 | # ifdef __s390x__ |
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| 28 | # define INSN "cgdbra" |
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| 29 | # else |
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| 30 | # define INSN "cfdbra" |
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| 31 | # endif |
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| 32 | |
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| 33 | long int |
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| 34 | __lround (double x) |
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| 35 | { |
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| 36 | long int y; |
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| 37 | /* The z196 zarch "convert to fixed" (cgdbra) instruction is rounding |
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| 38 | x to the nearest integer with "ties away from 0" rounding mode |
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| 39 | (M3-field: 1) where inexact exceptions are suppressed (M4-field: 4). */ |
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| 40 | __asm__ (INSN " %0,1,%1,4" : "=d" (y) : "f" (x) : "cc" ); |
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| 41 | return y; |
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| 42 | } |
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| 43 | libm_alias_double (__lround, lround) |
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| 44 | |
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| 45 | #else |
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| 46 | # include <sysdeps/ieee754/dbl-64/s_lround.c> |
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| 47 | #endif |
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| 48 | |
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