/*** FAAD2 - Freeware Advanced Audio (AAC) Decoder including SBR decoding** Copyright (C) 2003-2005 M. Bakker, Nero AG, http://www.nero.com**** 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, write to the Free Software** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.**** Any non-GPL usage of this software or parts of this software is strictly** forbidden.**** The "appropriate copyright message" mentioned in section 2c of the GPLv2** must read: "Code from FAAD2 is copyright (c) Nero AG, www.nero.com"**** Commercial non-GPL licensing of this software is possible.** For more info contact Nero AG through Mpeg4AAClicense@nero.com.**** $Id: common.c,v 1.27 2008/03/23 23:03:28 menno Exp $**/ /* just some common functions that could be used anywhere */ #include "common.h"#include "structs.h" #include "syntax.h"  /* Returns the sample rate index based on the samplerate */uint8_t get_sr_index(const uint32_t samplerate){    if (92017 <= samplerate) return 0;    if (75132 <= samplerate) return 1;    if (55426 <= samplerate) return 2;    if (46009 <= samplerate) return 3;    if (37566 <= samplerate) return 4;    if (27713 <= samplerate) return 5;    if (23004 <= samplerate) return 6;    if (18783 <= samplerate) return 7;    if (13856 <= samplerate) return 8;    if (11502 <= samplerate) return 9;    if (9391 <= samplerate) return 10;     return 11;} /* Returns the sample rate based on the sample rate index */uint32_t get_sample_rate(const uint8_t sr_index){    static const uint32_t sample_rates[] =    {        96000, 88200, 64000, 48000, 44100, 32000,        24000, 22050, 16000, 12000, 11025, 8000    };     if (sr_index < 12)        return sample_rates[sr_index];     return 0;} uint8_t max_pred_sfb(const uint8_t sr_index){    static const uint8_t pred_sfb_max[] =    {        33, 33, 38, 40, 40, 40, 41, 41, 37, 37, 37, 34    };      if (sr_index < 12)        return pred_sfb_max[sr_index];     return 0;} uint8_t max_tns_sfb(const uint8_t sr_index, const uint8_t object_type,                    const uint8_t is_short){    /* entry for each sampling rate     * 1    Main/LC long window     * 2    Main/LC short window     * 3    SSR long window     * 4    SSR short window     */    static const uint8_t tns_sbf_max[][4] =    {        {31,  9, 28, 7}, /* 96000 */        {31,  9, 28, 7}, /* 88200 */        {34, 10, 27, 7}, /* 64000 */        {40, 14, 26, 6}, /* 48000 */        {42, 14, 26, 6}, /* 44100 */        {51, 14, 26, 6}, /* 32000 */        {46, 14, 29, 7}, /* 24000 */        {46, 14, 29, 7}, /* 22050 */        {42, 14, 23, 8}, /* 16000 */        {42, 14, 23, 8}, /* 12000 */        {42, 14, 23, 8}, /* 11025 */        {39, 14, 19, 7}, /*  8000 */        {39, 14, 19, 7}, /*  7350 */        {0,0,0,0},        {0,0,0,0},        {0,0,0,0}    };    uint8_t i = 0;     if (is_short) i++;    if (object_type == SSR) i += 2;     return tns_sbf_max[sr_index][i];} /* Returns 0 if an object type is decodable, otherwise returns -1 */int8_t can_decode_ot(const uint8_t object_type){    switch (object_type)    {    case LC:        return 0;    case MAIN:#ifdef MAIN_DEC        return 0;#else        return -1;#endif    case SSR:#ifdef SSR_DEC        return 0;#else        return -1;#endif    case LTP:#ifdef LTP_DEC        return 0;#else        return -1;#endif     /* ER object types */#ifdef ERROR_RESILIENCE    case ER_LC:#ifdef DRM    case DRM_ER_LC:#endif        return 0;    case ER_LTP:#ifdef LTP_DEC        return 0;#else        return -1;#endif    case LD:#ifdef LD_DEC        return 0;#else        return -1;#endif#endif    }     return -1;} void *faad_malloc(size_t size){#if 0 // defined(_WIN32) && !defined(_WIN32_WCE)    return _aligned_malloc(size, 16);#else   // #ifdef 0    return malloc(size);#endif  // #ifdef 0} /* common free function */void faad_free(void *b){#if 0 // defined(_WIN32) && !defined(_WIN32_WCE)    _aligned_free(b);#else    free(b);}#endif static const  uint8_t    Parity [256] = {  // parity    0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0,1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1,    1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1,0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0,    1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1,0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0,    0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0,1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1,    1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1,0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0,    0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0,1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1,    0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0,1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1,    1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1,0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0};  /* *  This is a simple random number generator with good quality for audio purposes. *  It consists of two polycounters with opposite rotation direction and different *  periods. The periods are coprime, so the total period is the product of both. * *     ------------------------------------------------------------------------------------------------- * +-> |31:30:29:28:27:26:25:24:23:22:21:20:19:18:17:16:15:14:13:12:11:10: 9: 8: 7: 6: 5: 4: 3: 2: 1: 0| * |   ------------------------------------------------------------------------------------------------- * |                                                                          |  |  |  |     |        | * |                                                                          +--+--+--+-XOR-+--------+ * |                                                                                      | * +--------------------------------------------------------------------------------------+ * *     ------------------------------------------------------------------------------------------------- *     |31:30:29:28:27:26:25:24:23:22:21:20:19:18:17:16:15:14:13:12:11:10: 9: 8: 7: 6: 5: 4: 3: 2: 1: 0| <-+ *     -------------------------------------------------------------------------------------------------   | *       |  |           |  |                                                                               | *       +--+----XOR----+--+                                                                               | *                |                                                                                        | *                +----------------------------------------------------------------------------------------+ * * *  The first has an period of 3*5*17*257*65537, the second of 7*47*73*178481, *  which gives a period of 18.410.713.077.675.721.215. The result is the *  XORed values of both generators. */uint32_t ne_rng(uint32_t *__r1, uint32_t *__r2){    uint32_t  t1, t2, t3, t4;     t3   = t1 = *__r1;  t4   = t2 = *__r2;      // Parity calculation is done via table lookup, this is also available    t1  &= 0xF5;        t2 >>= 25;              // on CPUs without parity, can be implemented in C and avoid unpredictable    t1   = Parity [t1]; t2  &= 0x63;            // jumps and slow rotate through the carry flag operations.    t1 <<= 31;          t2   = Parity [t2];     return (*__r1 = (t3 >> 1) | t1 ) ^ (*__r2 = (t4 + t4) | t2 );} #ifdef FIXED_POINT static uint32_t ones32(uint32_t x){    x -= ((x >> 1) & 0x55555555);    x = (((x >> 2) & 0x33333333) + (x & 0x33333333));    x = (((x >> 4) + x) & 0x0f0f0f0f);    x += (x >> 8);    x += (x >> 16);     return (x & 0x0000003f);} static uint32_t ones64(uint64_t x){    return ones32((uint32_t)x) + ones32(x >> 32);} static uint32_t floor_log2(uint64_t x){#if 1    x |= (x >> 1);    x |= (x >> 2);    x |= (x >> 4);    x |= (x >> 8);    x |= (x >> 16);    x |= (x >> 32);     return (ones64(x) - 1);#else    uint32_t count = 0;     while (x >>= 1)        count++;     return count;#endif} /* returns position of first bit that is not 0 from msb, * starting count at lsb */uint32_t wl_min_lzc(uint32_t x){#if 1    x |= (x >> 1);    x |= (x >> 2);    x |= (x >> 4);    x |= (x >> 8);    x |= (x >> 16);     return (ones32(x));#else    uint32_t count = 0;     while (x >>= 1)        count++;     return (count + 1);#endif} #define TABLE_BITS 6/* just take the maximum number of bits for interpolation */#define INTERP_BITS (REAL_BITS-TABLE_BITS) static const real_t pow2_tab[] = {    REAL_CONST(1.000000000000000), REAL_CONST(1.010889286051701), REAL_CONST(1.021897148654117),    REAL_CONST(1.033024879021228), REAL_CONST(1.044273782427414), REAL_CONST(1.055645178360557),    REAL_CONST(1.067140400676824), REAL_CONST(1.078760797757120), REAL_CONST(1.090507732665258),    REAL_CONST(1.102382583307841), REAL_CONST(1.114386742595892), REAL_CONST(1.126521618608242),    REAL_CONST(1.138788634756692), REAL_CONST(1.151189229952983), REAL_CONST(1.163724858777578),    REAL_CONST(1.176396991650281), REAL_CONST(1.189207115002721), REAL_CONST(1.202156731452703),    REAL_CONST(1.215247359980469), REAL_CONST(1.228480536106870), REAL_CONST(1.241857812073484),    REAL_CONST(1.255380757024691), REAL_CONST(1.269050957191733), REAL_CONST(1.282870016078778),    REAL_CONST(1.296839554651010), REAL_CONST(1.310961211524764), REAL_CONST(1.325236643159741),    REAL_CONST(1.339667524053303), REAL_CONST(1.354255546936893), REAL_CONST(1.369002422974591),    REAL_CONST(1.383909881963832), REAL_CONST(1.398979672538311), REAL_CONST(1.414213562373095),    REAL_CONST(1.429613338391970), REAL_CONST(1.445180806977047), REAL_CONST(1.460917794180647),    REAL_CONST(1.476826145939499), REAL_CONST(1.492907728291265), REAL_CONST(1.509164427593423),    REAL_CONST(1.525598150744538), REAL_CONST(1.542210825407941), REAL_CONST(1.559004400237837),    REAL_CONST(1.575980845107887), REAL_CONST(1.593142151342267), REAL_CONST(1.610490331949254),    REAL_CONST(1.628027421857348), REAL_CONST(1.645755478153965), REAL_CONST(1.663676580326736),    REAL_CONST(1.681792830507429), REAL_CONST(1.700106353718524), REAL_CONST(1.718619298122478),    REAL_CONST(1.737333835273706), REAL_CONST(1.756252160373300), REAL_CONST(1.775376492526521),    REAL_CONST(1.794709075003107), REAL_CONST(1.814252175500399), REAL_CONST(1.834008086409342),    REAL_CONST(1.853979125083386), REAL_CONST(1.874167634110300), REAL_CONST(1.894575981586966),    REAL_CONST(1.915206561397147), REAL_CONST(1.936061793492294), REAL_CONST(1.957144124175400),    REAL_CONST(1.978456026387951), REAL_CONST(2.000000000000000)}; static const real_t log2_tab[] = {    REAL_CONST(0.000000000000000), REAL_CONST(0.022367813028455), REAL_CONST(0.044394119358453),    REAL_CONST(0.066089190457772), REAL_CONST(0.087462841250339), REAL_CONST(0.108524456778169),    REAL_CONST(0.129283016944966), REAL_CONST(0.149747119504682), REAL_CONST(0.169925001442312),    REAL_CONST(0.189824558880017), REAL_CONST(0.209453365628950), REAL_CONST(0.228818690495881),    REAL_CONST(0.247927513443585), REAL_CONST(0.266786540694901), REAL_CONST(0.285402218862248),    REAL_CONST(0.303780748177103), REAL_CONST(0.321928094887362), REAL_CONST(0.339850002884625),    REAL_CONST(0.357552004618084), REAL_CONST(0.375039431346925), REAL_CONST(0.392317422778760),    REAL_CONST(0.409390936137702), REAL_CONST(0.426264754702098), REAL_CONST(0.442943495848728),    REAL_CONST(0.459431618637297), REAL_CONST(0.475733430966398), REAL_CONST(0.491853096329675),    REAL_CONST(0.507794640198696), REAL_CONST(0.523561956057013), REAL_CONST(0.539158811108031),    REAL_CONST(0.554588851677637), REAL_CONST(0.569855608330948), REAL_CONST(0.584962500721156),    REAL_CONST(0.599912842187128), REAL_CONST(0.614709844115208), REAL_CONST(0.629356620079610),    REAL_CONST(0.643856189774725), REAL_CONST(0.658211482751795), REAL_CONST(0.672425341971496),    REAL_CONST(0.686500527183218), REAL_CONST(0.700439718141092), REAL_CONST(0.714245517666123),    REAL_CONST(0.727920454563199), REAL_CONST(0.741466986401147), REAL_CONST(0.754887502163469),    REAL_CONST(0.768184324776926), REAL_CONST(0.781359713524660), REAL_CONST(0.794415866350106),    REAL_CONST(0.807354922057604), REAL_CONST(0.820178962415188), REAL_CONST(0.832890014164742),    REAL_CONST(0.845490050944375), REAL_CONST(0.857980995127572), REAL_CONST(0.870364719583405),    REAL_CONST(0.882643049361841), REAL_CONST(0.894817763307943), REAL_CONST(0.906890595608519),    REAL_CONST(0.918863237274595), REAL_CONST(0.930737337562886), REAL_CONST(0.942514505339240),    REAL_CONST(0.954196310386875), REAL_CONST(0.965784284662087), REAL_CONST(0.977279923499917),    REAL_CONST(0.988684686772166), REAL_CONST(1.000000000000000)}; real_t pow2_fix(real_t val){    uint32_t x1, x2;    uint32_t errcorr;    uint32_t index_frac;    real_t retval;    int32_t whole = (val >> REAL_BITS); #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION    if (whole >= 17) __builtin_trap();#endif     /* rest = [0..1] */    int32_t rest = val & ((1 << REAL_BITS) - 1);     /* index into pow2_tab */    int32_t index = rest >> (REAL_BITS-TABLE_BITS);      if (val == 0)        return (1<<REAL_BITS);    if (REAL_BITS + whole < 0)        return 0;     /* leave INTERP_BITS bits */    index_frac = rest >> (REAL_BITS-TABLE_BITS-INTERP_BITS);    index_frac = index_frac & ((1<<INTERP_BITS)-1);     if (whole > 0)    {        retval = 1 << whole;    } else {        retval = REAL_CONST(1) >> -whole;    }     x1 = pow2_tab[index & ((1<<TABLE_BITS)-1)];    x2 = pow2_tab[(index & ((1<<TABLE_BITS)-1)) + 1];    errcorr = ( (index_frac*(x2-x1))) >> INTERP_BITS;     if (whole > 0)    {        retval = retval * (errcorr + x1);    } else {        retval = MUL_R(retval, (errcorr + x1));    }     return retval;} uint64_t pow2_int(real_t val){    uint32_t x1, x2;    uint32_t errcorr;    uint32_t index_frac;    uint64_t retval;    int32_t whole = (val >> REAL_BITS);    int32_t exp = 0;     /* rest = [0..1] */    int32_t rest = val & ((1 << REAL_BITS) - 1);     /* index into pow2_tab */    int32_t index = rest >> (REAL_BITS-TABLE_BITS);     if (val < 0)        return 0;    if (val == 0)        return 1;    if (whole > COEF_BITS) {        exp = whole - COEF_BITS;        whole = COEF_BITS;    }     /* leave INTERP_BITS bits */    index_frac = rest >> (REAL_BITS-TABLE_BITS-INTERP_BITS);    index_frac = index_frac & ((1<<INTERP_BITS)-1);     if (whole >= 0)        retval = (uint32_t)(1 << whole);    else        retval = 0;     x1 = pow2_tab[index & ((1<<TABLE_BITS)-1)];    x2 = pow2_tab[(index & ((1<<TABLE_BITS)-1)) + 1];    errcorr = ((index_frac*(x2-x1))) >> INTERP_BITS;     retval = MUL_R(retval, (errcorr + x1));     return retval << exp;} /* ld(x) = ld(x*y/y) = ld(x/y) + ld(y), with y=2^N and [1 <= (x/y) < 2] */int32_t log2_int(uint64_t val){    uint32_t frac;    int32_t exp = 0;    uint32_t index;    uint32_t index_frac;    uint32_t x1, x2;    uint32_t errcorr; #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION    if (val == 0) __builtin_trap();#endif     exp = floor_log2(val);    exp -= REAL_BITS;     /* frac = [1..2] */    if (exp >= 0)        frac = (uint32_t)(val >> exp);    else        frac = (uint32_t)(val << -exp);     /* index in the log2 table */    index = frac >> (REAL_BITS-TABLE_BITS);     /* leftover part for linear interpolation */    index_frac = frac & ((1<<(REAL_BITS-TABLE_BITS))-1);     /* leave INTERP_BITS bits */    index_frac = index_frac >> (REAL_BITS-TABLE_BITS-INTERP_BITS);     x1 = log2_tab[index & ((1<<TABLE_BITS)-1)];    x2 = log2_tab[(index & ((1<<TABLE_BITS)-1)) + 1];     /* linear interpolation */    /* retval = exp + ((index_frac)*x2 + (1-index_frac)*x1) */     errcorr = (index_frac * (x2-x1)) >> INTERP_BITS;     return ((exp+REAL_BITS) << REAL_BITS) + errcorr + x1;} #endif