libavutil/arm/intmath.h

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/*
 * Copyright (c) 2010 Mans Rullgard <mans@mansr.com>
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#ifndef AVUTIL_ARM_INTMATH_H
#define AVUTIL_ARM_INTMATH_H

#include "config.h"
#include "libavutil/attributes.h"

#if HAVE_INLINE_ASM

#if HAVE_ARMV6
static inline av_const int FASTDIV(int a, int b)
{
    int r, t;
    __asm__ volatile("cmp     %3, #2               \n\t"
                     "ldr     %1, [%4, %3, lsl #2] \n\t"
                     "lsrle   %0, %2, #1           \n\t"
                     "smmulgt %0, %1, %2           \n\t"
                     : "=&r"(r), "=&r"(t) : "r"(a), "r"(b), "r"(ff_inverse));
    return r;
}
#else
static inline av_const int FASTDIV(int a, int b)
{
    int r, t;
    __asm__ volatile("umull %1, %0, %2, %3"
                     : "=&r"(r), "=&r"(t) : "r"(a), "r"(ff_inverse[b]));
    return r;
}
#endif

#define FASTDIV FASTDIV

#endif /* HAVE_INLINE_ASM */

#endif /* AVUTIL_ARM_INTMATH_H */

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