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61 lines
1.9 KiB
C
61 lines
1.9 KiB
C
/* scalb(). LoongArch version.
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Copyright (C) 2022-2024 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with the GNU C Library; if not, see
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<https://www.gnu.org/licenses/>. */
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#define NO_MATH_REDIRECT
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#include <math.h>
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#include <libm-alias-finite.h>
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#include <fpu_control.h>
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#include <float.h>
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double
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__ieee754_scalb (double x, double fn)
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{
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int x_cond;
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int fn_cond;
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asm volatile ("fclass.d \t%0, %1" : "=f" (x_cond) : "f" (x));
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asm volatile ("fclass.d \t%0, %1" : "=f" (fn_cond) : "f" (fn));
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if (__glibc_unlikely(( x_cond | fn_cond) & _FCLASS_NAN))
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return x * fn;
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else if (__glibc_unlikely(fn_cond & _FCLASS_INF))
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{
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if (!(fn_cond & _FCLASS_MINF))
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return x * fn;
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else
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return x / -fn;
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}
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else if (__glibc_likely(-DBL_MAX < fn && fn < DBL_MAX))
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{
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double rint_fn, tmp;
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/* rint_fn = rint(fn) */
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asm volatile ("frint.d \t%0, %1" : "=f" (rint_fn) : "f" (fn));
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if (rint_fn != fn )
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return (x - x) / (x - x);
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asm volatile ("ftintrz.l.d \t%0, %1" : "=f" (tmp) : "f" (rint_fn));
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asm volatile ("fscaleb.d \t%0, %1, %2" : "=f" (x) : "f" (x), "f" (tmp));
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}
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else
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asm volatile ("fscaleb.d \t%0, %1, %2" : "=f" (x) : "f" (x), "f" (fn));
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return x;
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}
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libm_alias_finite (__ieee754_scalb, __scalb)
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