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db57f29d50
The code in _sp_maddf (formerly ieee754sp_madd) appears to have been
copied verbatim from ieee754sp_add, and although it's adding the
unpacked "r" & "z" floats it kept using macros that operate on "x" &
"y". This led to the addition being carried out incorrectly on some
mismash of the product, accumulator & multiplicand fields. Typically
this would lead to the assertions "ze == re" & "ze <= SP_EMAX" failing
since ze & re hadn't been operated upon.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Fixes: e24c3bec3e ("MIPS: math-emu: Add support for the MIPS R6 MADDF FPU instruction")
Cc: Adam Buchbinder <adam.buchbinder@gmail.com>
Cc: Maciej W. Rozycki <macro@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/13159/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
86 lines
2.2 KiB
C
86 lines
2.2 KiB
C
/*
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* IEEE754 floating point
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* double precision internal header file
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*/
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/*
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* MIPS floating point support
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* Copyright (C) 1994-2000 Algorithmics Ltd.
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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 (Version 2) as
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* published by the Free Software Foundation.
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*
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* This program is distributed in the hope it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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* for more details.
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*
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* You should have received a copy of the GNU General Public License along
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* with this program; if not, write to the Free Software Foundation, Inc.,
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* 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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*/
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#include <linux/compiler.h>
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#include "ieee754int.h"
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#define assert(expr) ((void)0)
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#define SP_EBIAS 127
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#define SP_EMIN (-126)
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#define SP_EMAX 127
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#define SP_FBITS 23
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#define SP_MBITS 23
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#define SP_MBIT(x) ((u32)1 << (x))
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#define SP_HIDDEN_BIT SP_MBIT(SP_FBITS)
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#define SP_SIGN_BIT SP_MBIT(31)
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#define SPSIGN(sp) (sp.sign)
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#define SPBEXP(sp) (sp.bexp)
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#define SPMANT(sp) (sp.mant)
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static inline int ieee754sp_finite(union ieee754sp x)
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{
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return SPBEXP(x) != SP_EMAX + 1 + SP_EBIAS;
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}
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/* 3bit extended single precision sticky right shift */
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#define XSPSRS(v, rs) \
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((rs > (SP_FBITS+3))?1:((v) >> (rs)) | ((v) << (32-(rs)) != 0))
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#define XSPSRS1(m) \
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((m >> 1) | (m & 1))
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#define SPXSRSX1() \
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(xe++, (xm = XSPSRS1(xm)))
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#define SPXSRSY1() \
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(ye++, (ym = XSPSRS1(ym)))
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/* convert denormal to normalized with extended exponent */
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#define SPDNORMx(m,e) \
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while ((m >> SP_FBITS) == 0) { m <<= 1; e--; }
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#define SPDNORMX SPDNORMx(xm, xe)
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#define SPDNORMY SPDNORMx(ym, ye)
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#define SPDNORMZ SPDNORMx(zm, ze)
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static inline union ieee754sp buildsp(int s, int bx, unsigned m)
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{
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union ieee754sp r;
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assert((s) == 0 || (s) == 1);
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assert((bx) >= SP_EMIN - 1 + SP_EBIAS
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&& (bx) <= SP_EMAX + 1 + SP_EBIAS);
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assert(((m) >> SP_FBITS) == 0);
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r.sign = s;
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r.bexp = bx;
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r.mant = m;
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return r;
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}
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extern union ieee754sp __cold ieee754sp_nanxcpt(union ieee754sp);
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extern union ieee754sp ieee754sp_format(int, int, unsigned);
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