30 lines
738 B
C
30 lines
738 B
C
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/* $NetBSD: fpsetround.c,v 1.5 2009/01/25 16:44:41 skrll Exp $ */
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/* $OpenBSD: fpsetround.c,v 1.3 2002/10/21 18:41:05 mickey Exp $ */
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/*
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* Written by Miodrag Vallat. Public domain
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*/
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#include <sys/cdefs.h>
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#if defined(LIBC_SCCS) && !defined(lint)
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__RCSID("$NetBSD: fpsetround.c,v 1.5 2009/01/25 16:44:41 skrll Exp $");
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#endif /* LIBC_SCCS and not lint */
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#include <sys/types.h>
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#include <ieeefp.h>
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fp_rnd
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fpsetround(fp_rnd rnd_dir)
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{
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uint64_t fpsr;
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fp_rnd old;
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__asm volatile("fstd %%fr0,0(%1)" : "=m" (fpsr) : "r" (&fpsr) : "memory");
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old = (fpsr >> 41) & 0x03;
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fpsr = (fpsr & 0xfffff9ff00000000LL) |
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((uint64_t)(rnd_dir & 0x03) << 41);
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__asm volatile("fldd 0(%0),%%fr0" : : "r" (&fpsr) : "memory");
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return (old);
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}
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