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diff --git a/libavutil/softfloat.h b/libavutil/softfloat.h
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+/*
+ * Copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
+ *
+ * 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_SOFTFLOAT_H
+#define AVUTIL_SOFTFLOAT_H
+
+#include <stdint.h>
+#include "common.h"
+
+#include "avassert.h"
+#include "softfloat_tables.h"
+
+#define MIN_EXP -126
+#define MAX_EXP 126
+#define ONE_BITS 29
+
+typedef struct SoftFloat{
+ int32_t mant;
+ int32_t exp;
+}SoftFloat;
+
+static const SoftFloat FLOAT_0 = { 0, MIN_EXP}; ///< 0.0
+static const SoftFloat FLOAT_05 = { 0x20000000, 0}; ///< 0.5
+static const SoftFloat FLOAT_1 = { 0x20000000, 1}; ///< 1.0
+static const SoftFloat FLOAT_EPSILON = { 0x29F16B12, -16}; ///< A small value
+static const SoftFloat FLOAT_1584893192 = { 0x32B771ED, 1}; ///< 1.584893192 (10^.2)
+static const SoftFloat FLOAT_100000 = { 0x30D40000, 17}; ///< 100000
+static const SoftFloat FLOAT_0999999 = { 0x3FFFFBCE, 0}; ///< 0.999999
+
+
+/**
+ * Convert a SoftFloat to a double precision float.
+ */
+static inline av_const double av_sf2double(SoftFloat v) {
+ v.exp -= ONE_BITS +1;
+ if(v.exp > 0) return (double)v.mant * (double)(1 << v.exp);
+ else return (double)v.mant / (double)(1 << (-v.exp));
+}
+
+static av_const SoftFloat av_normalize_sf(SoftFloat a){
+ if(a.mant){
+#if 1
+ while((a.mant + 0x1FFFFFFFU)<0x3FFFFFFFU){
+ a.mant += a.mant;
+ a.exp -= 1;
+ }
+#else
+ int s=ONE_BITS - av_log2(FFABS(a.mant));
+ a.exp -= s;
+ a.mant <<= s;
+#endif
+ if(a.exp < MIN_EXP){
+ a.exp = MIN_EXP;
+ a.mant= 0;
+ }
+ }else{
+ a.exp= MIN_EXP;
+ }
+ return a;
+}
+
+static inline av_const SoftFloat av_normalize1_sf(SoftFloat a){
+#if 1
+ if((int32_t)(a.mant + 0x40000000U) <= 0){
+ a.exp++;
+ a.mant>>=1;
+ }
+ av_assert2(a.mant < 0x40000000 && a.mant > -0x40000000);
+ av_assert2(a.exp <= MAX_EXP);
+ return a;
+#elif 1
+ int t= a.mant + 0x40000000 < 0;
+ return (SoftFloat){ a.mant>>t, a.exp+t};
+#else
+ int t= (a.mant + 0x3FFFFFFFU)>>31;
+ return (SoftFloat){a.mant>>t, a.exp+t};
+#endif
+}
+
+/**
+ * @return Will not be more denormalized than a*b. So if either input is
+ * normalized, then the output will not be worse then the other input.
+ * If both are normalized, then the output will be normalized.
+ */
+static inline av_const SoftFloat av_mul_sf(SoftFloat a, SoftFloat b){
+ a.exp += b.exp;
+ av_assert2((int32_t)((a.mant * (int64_t)b.mant) >> ONE_BITS) == (a.mant * (int64_t)b.mant) >> ONE_BITS);
+ a.mant = (a.mant * (int64_t)b.mant) >> ONE_BITS;
+ a = av_normalize1_sf((SoftFloat){a.mant, a.exp - 1});
+ if (!a.mant || a.exp < MIN_EXP)
+ return FLOAT_0;
+ return a;
+}
+
+/**
+ * b has to be normalized and not zero.
+ * @return Will not be more denormalized than a.
+ */
+static inline av_const SoftFloat av_div_sf(SoftFloat a, SoftFloat b){
+ a.exp -= b.exp;
+ a.mant = ((int64_t)a.mant<<(ONE_BITS+1)) / b.mant;
+ a = av_normalize1_sf(a);
+ if (!a.mant || a.exp < MIN_EXP)
+ return FLOAT_0;
+ return a;
+}
+
+/**
+ * Compares two SoftFloats.
+ * @returns < 0 if the first is less
+ * > 0 if the first is greater
+ * 0 if they are equal
+ */
+static inline av_const int av_cmp_sf(SoftFloat a, SoftFloat b){
+ int t= a.exp - b.exp;
+ if (t <-31) return - b.mant ;
+ else if (t < 0) return (a.mant >> (-t)) - b.mant ;
+ else if (t < 32) return a.mant - (b.mant >> t);
+ else return a.mant ;
+}
+
+/**
+ * Compares two SoftFloats.
+ * @returns 1 if a is greater than b, 0 otherwise
+ */
+static inline av_const int av_gt_sf(SoftFloat a, SoftFloat b)
+{
+ int t= a.exp - b.exp;
+ if (t <-31) return 0 > b.mant ;
+ else if (t < 0) return (a.mant >> (-t)) > b.mant ;
+ else if (t < 32) return a.mant > (b.mant >> t);
+ else return a.mant > 0 ;
+}
+
+/**
+ * @returns the sum of 2 SoftFloats.
+ */
+static inline av_const SoftFloat av_add_sf(SoftFloat a, SoftFloat b){
+ int t= a.exp - b.exp;
+ if (t <-31) return b;
+ else if (t < 0) return av_normalize_sf(av_normalize1_sf((SoftFloat){ b.mant + (a.mant >> (-t)), b.exp}));
+ else if (t < 32) return av_normalize_sf(av_normalize1_sf((SoftFloat){ a.mant + (b.mant >> t ), a.exp}));
+ else return a;
+}
+
+/**
+ * @returns the difference of 2 SoftFloats.
+ */
+static inline av_const SoftFloat av_sub_sf(SoftFloat a, SoftFloat b){
+ return av_add_sf(a, (SoftFloat){ -b.mant, b.exp});
+}
+
+//FIXME log, exp, pow
+
+/**
+ * Converts a mantisse and exponent to a SoftFloat
+ * @returns a SoftFloat with value v * 2^frac_bits
+ */
+static inline av_const SoftFloat av_int2sf(int v, int frac_bits){
+ int exp_offset = 0;
+ if(v == INT_MIN){
+ exp_offset = 1;
+ v>>=1;
+ }
+ return av_normalize_sf(av_normalize1_sf((SoftFloat){v, ONE_BITS + 1 - frac_bits + exp_offset}));
+}
+
+/**
+ * Converts a SoftFloat to an integer.
+ * Rounding is to -inf.
+ */
+static inline av_const int av_sf2int(SoftFloat v, int frac_bits){
+ v.exp += frac_bits - (ONE_BITS + 1);
+ if(v.exp >= 0) return v.mant << v.exp ;
+ else return v.mant >>(-v.exp);
+}
+
+/**
+ * Rounding-to-nearest used.
+ */
+static av_always_inline SoftFloat av_sqrt_sf(SoftFloat val)
+{
+ int tabIndex, rem;
+
+ if (val.mant == 0)
+ val.exp = MIN_EXP;
+ else if (val.mant < 0)
+ abort();
+ else
+ {
+ tabIndex = (val.mant - 0x20000000) >> 20;
+
+ rem = val.mant & 0xFFFFF;
+ val.mant = (int)(((int64_t)av_sqrttbl_sf[tabIndex] * (0x100000 - rem) +
+ (int64_t)av_sqrttbl_sf[tabIndex + 1] * rem +
+ 0x80000) >> 20);
+ val.mant = (int)(((int64_t)av_sqr_exp_multbl_sf[val.exp & 1] * val.mant +
+ 0x10000000) >> 29);
+
+ if (val.mant < 0x40000000)
+ val.exp -= 2;
+ else
+ val.mant >>= 1;
+
+ val.exp = (val.exp >> 1) + 1;
+ }
+
+ return val;
+}
+
+/**
+ * Rounding-to-nearest used.
+ */
+static av_unused void av_sincos_sf(int a, int *s, int *c)
+{
+ int idx, sign;
+ int sv, cv;
+ int st, ct;
+
+ idx = a >> 26;
+ sign = (idx << 27) >> 31;
+ cv = av_costbl_1_sf[idx & 0xf];
+ cv = (cv ^ sign) - sign;
+
+ idx -= 8;
+ sign = (idx << 27) >> 31;
+ sv = av_costbl_1_sf[idx & 0xf];
+ sv = (sv ^ sign) - sign;
+
+ idx = a >> 21;
+ ct = av_costbl_2_sf[idx & 0x1f];
+ st = av_sintbl_2_sf[idx & 0x1f];
+
+ idx = (int)(((int64_t)cv * ct - (int64_t)sv * st + 0x20000000) >> 30);
+
+ sv = (int)(((int64_t)cv * st + (int64_t)sv * ct + 0x20000000) >> 30);
+
+ cv = idx;
+
+ idx = a >> 16;
+ ct = av_costbl_3_sf[idx & 0x1f];
+ st = av_sintbl_3_sf[idx & 0x1f];
+
+ idx = (int)(((int64_t)cv * ct - (int64_t)sv * st + 0x20000000) >> 30);
+
+ sv = (int)(((int64_t)cv * st + (int64_t)sv * ct + 0x20000000) >> 30);
+ cv = idx;
+
+ idx = a >> 11;
+
+ ct = (int)(((int64_t)av_costbl_4_sf[idx & 0x1f] * (0x800 - (a & 0x7ff)) +
+ (int64_t)av_costbl_4_sf[(idx & 0x1f)+1]*(a & 0x7ff) +
+ 0x400) >> 11);
+ st = (int)(((int64_t)av_sintbl_4_sf[idx & 0x1f] * (0x800 - (a & 0x7ff)) +
+ (int64_t)av_sintbl_4_sf[(idx & 0x1f) + 1] * (a & 0x7ff) +
+ 0x400) >> 11);
+
+ *c = (int)(((int64_t)cv * ct + (int64_t)sv * st + 0x20000000) >> 30);
+
+ *s = (int)(((int64_t)cv * st + (int64_t)sv * ct + 0x20000000) >> 30);
+}
+
+#endif /* AVUTIL_SOFTFLOAT_H */
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