![Markos Chandras](/assets/img/avatar_default.png)
MIPS R6 introduced the following instruction: Stores in fd a bit mask reflecting the floating-point class of the floating point scalar value fs. CLASS.fmt: FPR[fd] = class(FPR[fs]) Signed-off-by: Markos Chandras <markos.chandras@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/10959/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
56 lines
1.1 KiB
C
56 lines
1.1 KiB
C
/*
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* IEEE754 floating point arithmetic
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* single precision: CLASS.f
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* FPR[fd] = class(FPR[fs])
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*
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* MIPS floating point support
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* Copyright (C) 2015 Imagination Technologies, Ltd.
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* Author: Markos Chandras <markos.chandras@imgtec.com>
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*
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* This program is free software; you can distribute it and/or modify it
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* under the terms of the GNU General Public License as published by the
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* Free Software Foundation; version 2 of the License.
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*/
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#include "ieee754sp.h"
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int ieee754sp_2008class(union ieee754sp x)
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{
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COMPXSP;
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EXPLODEXSP;
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/*
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* 10 bit mask as follows:
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*
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* bit0 = SNAN
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* bit1 = QNAN
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* bit2 = -INF
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* bit3 = -NORM
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* bit4 = -DNORM
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* bit5 = -ZERO
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* bit6 = INF
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* bit7 = NORM
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* bit8 = DNORM
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* bit9 = ZERO
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*/
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switch(xc) {
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case IEEE754_CLASS_SNAN:
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return 0x01;
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case IEEE754_CLASS_QNAN:
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return 0x02;
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case IEEE754_CLASS_INF:
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return 0x04 << (xs ? 0 : 4);
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case IEEE754_CLASS_NORM:
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return 0x08 << (xs ? 0 : 4);
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case IEEE754_CLASS_DNORM:
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return 0x10 << (xs ? 0 : 4);
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case IEEE754_CLASS_ZERO:
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return 0x20 << (xs ? 0 : 4);
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default:
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pr_err("Unknown class: %d\n", xc);
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return 0;
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}
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}
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