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Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not see the file copying or write to the free software foundation inc extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 12 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Richard Fontana <rfontana@redhat.com> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190523091651.231300438@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
61 lines
1.7 KiB
C
61 lines
1.7 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
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/*
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*/
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#include <linux/export.h>
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#include <linux/libgcc.h>
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#define W_TYPE_SIZE 32
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#define __ll_B ((unsigned long) 1 << (W_TYPE_SIZE / 2))
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#define __ll_lowpart(t) ((unsigned long) (t) & (__ll_B - 1))
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#define __ll_highpart(t) ((unsigned long) (t) >> (W_TYPE_SIZE / 2))
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/* If we still don't have umul_ppmm, define it using plain C. */
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#if !defined(umul_ppmm)
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#define umul_ppmm(w1, w0, u, v) \
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do { \
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unsigned long __x0, __x1, __x2, __x3; \
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unsigned short __ul, __vl, __uh, __vh; \
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\
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__ul = __ll_lowpart(u); \
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__uh = __ll_highpart(u); \
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__vl = __ll_lowpart(v); \
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__vh = __ll_highpart(v); \
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\
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__x0 = (unsigned long) __ul * __vl; \
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__x1 = (unsigned long) __ul * __vh; \
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__x2 = (unsigned long) __uh * __vl; \
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__x3 = (unsigned long) __uh * __vh; \
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\
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__x1 += __ll_highpart(__x0); /* this can't give carry */\
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__x1 += __x2; /* but this indeed can */ \
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if (__x1 < __x2) /* did we get it? */ \
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__x3 += __ll_B; /* yes, add it in the proper pos */ \
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\
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(w1) = __x3 + __ll_highpart(__x1); \
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(w0) = __ll_lowpart(__x1) * __ll_B + __ll_lowpart(__x0);\
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} while (0)
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#endif
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#if !defined(__umulsidi3)
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#define __umulsidi3(u, v) ({ \
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DWunion __w; \
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umul_ppmm(__w.s.high, __w.s.low, u, v); \
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__w.ll; \
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})
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#endif
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long long notrace __muldi3(long long u, long long v)
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{
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const DWunion uu = {.ll = u};
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const DWunion vv = {.ll = v};
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DWunion w = {.ll = __umulsidi3(uu.s.low, vv.s.low)};
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w.s.high += ((unsigned long) uu.s.low * (unsigned long) vv.s.high
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+ (unsigned long) uu.s.high * (unsigned long) vv.s.low);
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return w.ll;
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}
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EXPORT_SYMBOL(__muldi3);
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