Commit 54090456 authored by Fabian Bauer's avatar Fabian Bauer Committed by Manuel Jander
Browse files

add modified version of division '1/x'

parent b568c889

lib_com/basop_util.c

+13 −386
Original line number Diff line number Diff line
@@ -1066,414 +1066,41 @@ Word32 BASOP_Util_Divide3232_Scale_cadence( Word32 x, Word32 y, Word16 *s ) 
    return z;

}



#ifdef DIV32_OPT_NEWTON

Word32 div_w_newton( Word32 num, Word32 den );

/*

Table of 256 precalculated estimates to be used by the "div_w_newton"

function using the Newton/Raphson method.

Note: The first table value (for denominator near 0x40000000) is not fully

accurate and should not be used.

*/

Word32 div_w_newton_lookup[256] = {

    /* Precalculated rounded results for 0x40000000 / b with b in [0x40000000 ... 0x7FFFFFFF] */

    0x7FFFFFFF, //  1.000000000000000  i=0  0.5 / 0.5+0/512 (b=0x40000000)

    0x7F807F80, //  0.996108949416342  i=1  0.5 / 0.5+1/512 (b=0x40400000)

    0x7F01FC07, //  0.992248062015504  i=2  0.5 / 0.5+2/512 (b=0x40800000)

    0x7E8472A8, //  0.988416988416988  i=3  0.5 / 0.5+3/512 (b=0x40C00000)

    0x7E07E07E, //  0.984615384615385  i=4  0.5 / 0.5+4/512 (b=0x41000000)

    0x7D8C42B2, //  0.980842911877395  i=5  0.5 / 0.5+5/512 (b=0x41400000)

    0x7D119679, //  0.977099236641221  i=6  0.5 / 0.5+6/512 (b=0x41800000)

    0x7C97D910, //  0.973384030418251  i=7  0.5 / 0.5+7/512 (b=0x41C00000)

    0x7C1F07C1, //  0.969696969696970  i=8  0.5 / 0.5+8/512 (b=0x42000000)

    0x7BA71FE1, //  0.966037735849057  i=9  0.5 / 0.5+9/512 (b=0x42400000)

    0x7B301ECC, //  0.962406015037594  i=10  0.5 / 0.5+10/512 (b=0x42800000)

    0x7ABA01EA, //  0.958801498127341  i=11  0.5 / 0.5+11/512 (b=0x42C00000)

    0x7A44C6AF, //  0.955223880597015  i=12  0.5 / 0.5+12/512 (b=0x43000000)

    0x79D06A96, //  0.951672862453532  i=13  0.5 / 0.5+13/512 (b=0x43400000)

    0x795CEB24, //  0.948148148148148  i=14  0.5 / 0.5+14/512 (b=0x43800000)

    0x78EA45E7, //  0.944649446494465  i=15  0.5 / 0.5+15/512 (b=0x43C00000)

    0x78787878, //  0.941176470588235  i=16  0.5 / 0.5+16/512 (b=0x44000000)

    0x78078078, //  0.937728937728938  i=17  0.5 / 0.5+17/512 (b=0x44400000)

    0x77975B8F, //  0.934306569343066  i=18  0.5 / 0.5+18/512 (b=0x44800000)

    0x77280772, //  0.930909090909091  i=19  0.5 / 0.5+19/512 (b=0x44C00000)

    0x76B981DA, //  0.927536231884058  i=20  0.5 / 0.5+20/512 (b=0x45000000)

    0x764BC88C, //  0.924187725631769  i=21  0.5 / 0.5+21/512 (b=0x45400000)

    0x75DED952, //  0.920863309352518  i=22  0.5 / 0.5+22/512 (b=0x45800000)

    0x7572B201, //  0.917562724014337  i=23  0.5 / 0.5+23/512 (b=0x45C00000)

    0x75075075, //  0.914285714285714  i=24  0.5 / 0.5+24/512 (b=0x46000000)

    0x749CB28F, //  0.911032028469751  i=25  0.5 / 0.5+25/512 (b=0x46400000)

    0x7432D63D, //  0.907801418439716  i=26  0.5 / 0.5+26/512 (b=0x46800000)

    0x73C9B971, //  0.904593639575972  i=27  0.5 / 0.5+27/512 (b=0x46C00000)

    0x73615A24, //  0.901408450704225  i=28  0.5 / 0.5+28/512 (b=0x47000000)

    0x72F9B658, //  0.898245614035088  i=29  0.5 / 0.5+29/512 (b=0x47400000)

    0x7292CC15, //  0.895104895104895  i=30  0.5 / 0.5+30/512 (b=0x47800000)

    0x722C996B, //  0.891986062717770  i=31  0.5 / 0.5+31/512 (b=0x47C00000)

    0x71C71C71, //  0.888888888888889  i=32  0.5 / 0.5+32/512 (b=0x48000000)

    0x71625344, //  0.885813148788927  i=33  0.5 / 0.5+33/512 (b=0x48400000)

    0x70FE3C07, //  0.882758620689655  i=34  0.5 / 0.5+34/512 (b=0x48800000)

    0x709AD4E4, //  0.879725085910653  i=35  0.5 / 0.5+35/512 (b=0x48C00000)

    0x70381C0E, //  0.876712328767123  i=36  0.5 / 0.5+36/512 (b=0x49000000)

    0x6FD60FBA, //  0.873720136518771  i=37  0.5 / 0.5+37/512 (b=0x49400000)

    0x6F74AE26, //  0.870748299319728  i=38  0.5 / 0.5+38/512 (b=0x49800000)

    0x6F13F596, //  0.867796610169492  i=39  0.5 / 0.5+39/512 (b=0x49C00000)

    0x6EB3E453, //  0.864864864864865  i=40  0.5 / 0.5+40/512 (b=0x4A000000)

    0x6E5478AC, //  0.861952861952862  i=41  0.5 / 0.5+41/512 (b=0x4A400000)

    0x6DF5B0F7, //  0.859060402684564  i=42  0.5 / 0.5+42/512 (b=0x4A800000)

    0x6D978B8E, //  0.856187290969900  i=43  0.5 / 0.5+43/512 (b=0x4AC00000)

    0x6D3A06D3, //  0.853333333333333  i=44  0.5 / 0.5+44/512 (b=0x4B000000)

    0x6CDD212B, //  0.850498338870432  i=45  0.5 / 0.5+45/512 (b=0x4B400000)

    0x6C80D901, //  0.847682119205298  i=46  0.5 / 0.5+46/512 (b=0x4B800000)

    0x6C252CC7, //  0.844884488448845  i=47  0.5 / 0.5+47/512 (b=0x4BC00000)

    0x6BCA1AF2, //  0.842105263157895  i=48  0.5 / 0.5+48/512 (b=0x4C000000)

    0x6B6FA1FE, //  0.839344262295082  i=49  0.5 / 0.5+49/512 (b=0x4C400000)

    0x6B15C06B, //  0.836601307189543  i=50  0.5 / 0.5+50/512 (b=0x4C800000)

    0x6ABC74BE, //  0.833876221498371  i=51  0.5 / 0.5+51/512 (b=0x4CC00000)

    0x6A63BD81, //  0.831168831168831  i=52  0.5 / 0.5+52/512 (b=0x4D000000)

    0x6A0B9944, //  0.828478964401295  i=53  0.5 / 0.5+53/512 (b=0x4D400000)

    0x69B4069B, //  0.825806451612903  i=54  0.5 / 0.5+54/512 (b=0x4D800000)

    0x695D041D, //  0.823151125401929  i=55  0.5 / 0.5+55/512 (b=0x4DC00000)

    0x69069069, //  0.820512820512820  i=56  0.5 / 0.5+56/512 (b=0x4E000000)

    0x68B0AA1F, //  0.817891373801917  i=57  0.5 / 0.5+57/512 (b=0x4E400000)

    0x685B4FE5, //  0.815286624203822  i=58  0.5 / 0.5+58/512 (b=0x4E800000)

    0x68068068, //  0.812698412698413  i=59  0.5 / 0.5+59/512 (b=0x4EC00000)

    0x67B23A54, //  0.810126582278481  i=60  0.5 / 0.5+60/512 (b=0x4F000000)

    0x675E7C5D, //  0.807570977917981  i=61  0.5 / 0.5+61/512 (b=0x4F400000)

    0x670B453B, //  0.805031446540881  i=62  0.5 / 0.5+62/512 (b=0x4F800000)

    0x66B893A9, //  0.802507836990596  i=63  0.5 / 0.5+63/512 (b=0x4FC00000)

    0x66666666, //  0.800000000000000  i=64  0.5 / 0.5+64/512 (b=0x50000000)

    0x6614BC36, //  0.797507788161994  i=65  0.5 / 0.5+65/512 (b=0x50400000)

    0x65C393E0, //  0.795031055900621  i=66  0.5 / 0.5+66/512 (b=0x50800000)

    0x6572EC2F, //  0.792569659442725  i=67  0.5 / 0.5+67/512 (b=0x50C00000)

    0x6522C3F3, //  0.790123456790123  i=68  0.5 / 0.5+68/512 (b=0x51000000)

    0x64D319FE, //  0.787692307692308  i=69  0.5 / 0.5+69/512 (b=0x51400000)

    0x6483ED27, //  0.785276073619632  i=70  0.5 / 0.5+70/512 (b=0x51800000)

    0x64353C48, //  0.782874617737003  i=71  0.5 / 0.5+71/512 (b=0x51C00000)

    0x63E7063E, //  0.780487804878049  i=72  0.5 / 0.5+72/512 (b=0x52000000)

    0x639949EB, //  0.778115501519757  i=73  0.5 / 0.5+73/512 (b=0x52400000)

    0x634C0634, //  0.775757575757576  i=74  0.5 / 0.5+74/512 (b=0x52800000)

    0x62FF3A01, //  0.773413897280967  i=75  0.5 / 0.5+75/512 (b=0x52C00000)

    0x62B2E43D, //  0.771084337349398  i=76  0.5 / 0.5+76/512 (b=0x53000000)

    0x626703D8, //  0.768768768768769  i=77  0.5 / 0.5+77/512 (b=0x53400000)

    0x621B97C2, //  0.766467065868264  i=78  0.5 / 0.5+78/512 (b=0x53800000)

    0x61D09EF3, //  0.764179104477612  i=79  0.5 / 0.5+79/512 (b=0x53C00000)

    0x61861861, //  0.761904761904762  i=80  0.5 / 0.5+80/512 (b=0x54000000)

    0x613C0309, //  0.759643916913947  i=81  0.5 / 0.5+81/512 (b=0x54400000)

    0x60F25DEA, //  0.757396449704142  i=82  0.5 / 0.5+82/512 (b=0x54800000)

    0x60A92806, //  0.755162241887906  i=83  0.5 / 0.5+83/512 (b=0x54C00000)

    0x60606060, //  0.752941176470588  i=84  0.5 / 0.5+84/512 (b=0x55000000)

    0x60180601, //  0.750733137829912  i=85  0.5 / 0.5+85/512 (b=0x55400000)

    0x5FD017F4, //  0.748538011695906  i=86  0.5 / 0.5+86/512 (b=0x55800000)

    0x5F889545, //  0.746355685131195  i=87  0.5 / 0.5+87/512 (b=0x55C00000)

    0x5F417D05, //  0.744186046511628  i=88  0.5 / 0.5+88/512 (b=0x56000000)

    0x5EFACE48, //  0.742028985507246  i=89  0.5 / 0.5+89/512 (b=0x56400000)

    0x5EB48823, //  0.739884393063584  i=90  0.5 / 0.5+90/512 (b=0x56800000)

    0x5E6EA9AE, //  0.737752161383285  i=91  0.5 / 0.5+91/512 (b=0x56C00000)

    0x5E293205, //  0.735632183908046  i=92  0.5 / 0.5+92/512 (b=0x57000000)

    0x5DE42046, //  0.733524355300860  i=93  0.5 / 0.5+93/512 (b=0x57400000)

    0x5D9F7390, //  0.731428571428571  i=94  0.5 / 0.5+94/512 (b=0x57800000)

    0x5D5B2B08, //  0.729344729344729  i=95  0.5 / 0.5+95/512 (b=0x57C00000)

    0x5D1745D1, //  0.727272727272727  i=96  0.5 / 0.5+96/512 (b=0x58000000)

    0x5CD3C315, //  0.725212464589235  i=97  0.5 / 0.5+97/512 (b=0x58400000)

    0x5C90A1FD, //  0.723163841807910  i=98  0.5 / 0.5+98/512 (b=0x58800000)

    0x5C4DE1B6, //  0.721126760563380  i=99  0.5 / 0.5+99/512 (b=0x58C00000)

    0x5C0B8170, //  0.719101123595506  i=100  0.5 / 0.5+100/512 (b=0x59000000)

    0x5BC9805B, //  0.717086834733894  i=101  0.5 / 0.5+101/512 (b=0x59400000)

    0x5B87DDAD, //  0.715083798882682  i=102  0.5 / 0.5+102/512 (b=0x59800000)

    0x5B46989A, //  0.713091922005571  i=103  0.5 / 0.5+103/512 (b=0x59C00000)

    0x5B05B05B, //  0.711111111111111  i=104  0.5 / 0.5+104/512 (b=0x5A000000)

    0x5AC5242A, //  0.709141274238227  i=105  0.5 / 0.5+105/512 (b=0x5A400000)

    0x5A84F345, //  0.707182320441989  i=106  0.5 / 0.5+106/512 (b=0x5A800000)

    0x5A451CEA, //  0.705234159779614  i=107  0.5 / 0.5+107/512 (b=0x5AC00000)

    0x5A05A05A, //  0.703296703296703  i=108  0.5 / 0.5+108/512 (b=0x5B000000)

    0x59C67CD8, //  0.701369863013699  i=109  0.5 / 0.5+109/512 (b=0x5B400000)

    0x5987B1A9, //  0.699453551912568  i=110  0.5 / 0.5+110/512 (b=0x5B800000)

    0x59493E14, //  0.697547683923706  i=111  0.5 / 0.5+111/512 (b=0x5BC00000)

    0x590B2164, //  0.695652173913043  i=112  0.5 / 0.5+112/512 (b=0x5C000000)

    0x58CD5AE2, //  0.693766937669377  i=113  0.5 / 0.5+113/512 (b=0x5C400000)

    0x588FE9DC, //  0.691891891891892  i=114  0.5 / 0.5+114/512 (b=0x5C800000)

    0x5852CDA0, //  0.690026954177898  i=115  0.5 / 0.5+115/512 (b=0x5CC00000)

    0x58160581, //  0.688172043010753  i=116  0.5 / 0.5+116/512 (b=0x5D000000)

    0x57D990D0, //  0.686327077747989  i=117  0.5 / 0.5+117/512 (b=0x5D400000)

    0x579D6EE3, //  0.684491978609626  i=118  0.5 / 0.5+118/512 (b=0x5D800000)

    0x57619F0F, //  0.682666666666667  i=119  0.5 / 0.5+119/512 (b=0x5DC00000)

    0x572620AE, //  0.680851063829787  i=120  0.5 / 0.5+120/512 (b=0x5E000000)

    0x56EAF319, //  0.679045092838196  i=121  0.5 / 0.5+121/512 (b=0x5E400000)

    0x56B015AC, //  0.677248677248677  i=122  0.5 / 0.5+122/512 (b=0x5E800000)

    0x567587C4, //  0.675461741424802  i=123  0.5 / 0.5+123/512 (b=0x5EC00000)

    0x563B48C2, //  0.673684210526316  i=124  0.5 / 0.5+124/512 (b=0x5F000000)

    0x56015805, //  0.671916010498688  i=125  0.5 / 0.5+125/512 (b=0x5F400000)

    0x55C7B4F1, //  0.670157068062827  i=126  0.5 / 0.5+126/512 (b=0x5F800000)

    0x558E5EE9, //  0.668407310704961  i=127  0.5 / 0.5+127/512 (b=0x5FC00000)

    0x55555555, //  0.666666666666667  i=128  0.5 / 0.5+128/512 (b=0x60000000)

    0x551C979A, //  0.664935064935065  i=129  0.5 / 0.5+129/512 (b=0x60400000)

    0x54E42523, //  0.663212435233161  i=130  0.5 / 0.5+130/512 (b=0x60800000)

    0x54ABFD5A, //  0.661498708010336  i=131  0.5 / 0.5+131/512 (b=0x60C00000)

    0x54741FAB, //  0.659793814432990  i=132  0.5 / 0.5+132/512 (b=0x61000000)

    0x543C8B84, //  0.658097686375321  i=133  0.5 / 0.5+133/512 (b=0x61400000)

    0x54054054, //  0.656410256410256  i=134  0.5 / 0.5+134/512 (b=0x61800000)

    0x53CE3D8B, //  0.654731457800512  i=135  0.5 / 0.5+135/512 (b=0x61C00000)

    0x5397829C, //  0.653061224489796  i=136  0.5 / 0.5+136/512 (b=0x62000000)

    0x53610EFB, //  0.651399491094148  i=137  0.5 / 0.5+137/512 (b=0x62400000)

    0x532AE21C, //  0.649746192893401  i=138  0.5 / 0.5+138/512 (b=0x62800000)

    0x52F4FB76, //  0.648101265822785  i=139  0.5 / 0.5+139/512 (b=0x62C00000)

    0x52BF5A81, //  0.646464646464647  i=140  0.5 / 0.5+140/512 (b=0x63000000)

    0x5289FEB5, //  0.644836272040302  i=141  0.5 / 0.5+141/512 (b=0x63400000)

    0x5254E78E, //  0.643216080402010  i=142  0.5 / 0.5+142/512 (b=0x63800000)

    0x52201488, //  0.641604010025063  i=143  0.5 / 0.5+143/512 (b=0x63C00000)

    0x51EB851E, //  0.640000000000000  i=144  0.5 / 0.5+144/512 (b=0x64000000)

    0x51B738D1, //  0.638403990024938  i=145  0.5 / 0.5+145/512 (b=0x64400000)

    0x51832F1F, //  0.636815920398010  i=146  0.5 / 0.5+146/512 (b=0x64800000)

    0x514F678B, //  0.635235732009926  i=147  0.5 / 0.5+147/512 (b=0x64C00000)

    0x511BE195, //  0.633663366336634  i=148  0.5 / 0.5+148/512 (b=0x65000000)

    0x50E89CC2, //  0.632098765432099  i=149  0.5 / 0.5+149/512 (b=0x65400000)

    0x50B59897, //  0.630541871921182  i=150  0.5 / 0.5+150/512 (b=0x65800000)

    0x5082D499, //  0.628992628992629  i=151  0.5 / 0.5+151/512 (b=0x65C00000)

    0x50505050, //  0.627450980392157  i=152  0.5 / 0.5+152/512 (b=0x66000000)

    0x501E0B44, //  0.625916870415648  i=153  0.5 / 0.5+153/512 (b=0x66400000)

    0x4FEC04FE, //  0.624390243902439  i=154  0.5 / 0.5+154/512 (b=0x66800000)

    0x4FBA3D0A, //  0.622871046228710  i=155  0.5 / 0.5+155/512 (b=0x66C00000)

    0x4F88B2F3, //  0.621359223300971  i=156  0.5 / 0.5+156/512 (b=0x67000000)

    0x4F576646, //  0.619854721549637  i=157  0.5 / 0.5+157/512 (b=0x67400000)

    0x4F265691, //  0.618357487922705  i=158  0.5 / 0.5+158/512 (b=0x67800000)

    0x4EF58364, //  0.616867469879518  i=159  0.5 / 0.5+159/512 (b=0x67C00000)

    0x4EC4EC4E, //  0.615384615384615  i=160  0.5 / 0.5+160/512 (b=0x68000000)

    0x4E9490E1, //  0.613908872901679  i=161  0.5 / 0.5+161/512 (b=0x68400000)

    0x4E6470B0, //  0.612440191387560  i=162  0.5 / 0.5+162/512 (b=0x68800000)

    0x4E348B4D, //  0.610978520286396  i=163  0.5 / 0.5+163/512 (b=0x68C00000)

    0x4E04E04E, //  0.609523809523810  i=164  0.5 / 0.5+164/512 (b=0x69000000)

    0x4DD56F47, //  0.608076009501188  i=165  0.5 / 0.5+165/512 (b=0x69400000)

    0x4DA637CF, //  0.606635071090047  i=166  0.5 / 0.5+166/512 (b=0x69800000)

    0x4D77397E, //  0.605200945626478  i=167  0.5 / 0.5+167/512 (b=0x69C00000)

    0x4D4873EC, //  0.603773584905660  i=168  0.5 / 0.5+168/512 (b=0x6A000000)

    0x4D19E6B3, //  0.602352941176471  i=169  0.5 / 0.5+169/512 (b=0x6A400000)

    0x4CEB916D, //  0.600938967136150  i=170  0.5 / 0.5+170/512 (b=0x6A800000)

    0x4CBD73B5, //  0.599531615925059  i=171  0.5 / 0.5+171/512 (b=0x6AC00000)

    0x4C8F8D28, //  0.598130841121495  i=172  0.5 / 0.5+172/512 (b=0x6B000000)

    0x4C61DD63, //  0.596736596736597  i=173  0.5 / 0.5+173/512 (b=0x6B400000)

    0x4C346404, //  0.595348837209302  i=174  0.5 / 0.5+174/512 (b=0x6B800000)

    0x4C0720AB, //  0.593967517401392  i=175  0.5 / 0.5+175/512 (b=0x6BC00000)

    0x4BDA12F6, //  0.592592592592593  i=176  0.5 / 0.5+176/512 (b=0x6C000000)

    0x4BAD3A87, //  0.591224018475751  i=177  0.5 / 0.5+177/512 (b=0x6C400000)

    0x4B809701, //  0.589861751152074  i=178  0.5 / 0.5+178/512 (b=0x6C800000)

    0x4B542804, //  0.588505747126437  i=179  0.5 / 0.5+179/512 (b=0x6CC00000)

    0x4B27ED36, //  0.587155963302752  i=180  0.5 / 0.5+180/512 (b=0x6D000000)

    0x4AFBE639, //  0.585812356979405  i=181  0.5 / 0.5+181/512 (b=0x6D400000)

    0x4AD012B4, //  0.584474885844749  i=182  0.5 / 0.5+182/512 (b=0x6D800000)

    0x4AA4724B, //  0.583143507972665  i=183  0.5 / 0.5+183/512 (b=0x6DC00000)

    0x4A7904A7, //  0.581818181818182  i=184  0.5 / 0.5+184/512 (b=0x6E000000)

    0x4A4DC96E, //  0.580498866213152  i=185  0.5 / 0.5+185/512 (b=0x6E400000)

    0x4A22C04A, //  0.579185520361991  i=186  0.5 / 0.5+186/512 (b=0x6E800000)

    0x49F7E8E2, //  0.577878103837472  i=187  0.5 / 0.5+187/512 (b=0x6EC00000)

    0x49CD42E2, //  0.576576576576577  i=188  0.5 / 0.5+188/512 (b=0x6F000000)

    0x49A2CDF3, //  0.575280898876405  i=189  0.5 / 0.5+189/512 (b=0x6F400000)

    0x497889C2, //  0.573991031390135  i=190  0.5 / 0.5+190/512 (b=0x6F800000)

    0x494E75FA, //  0.572706935123042  i=191  0.5 / 0.5+191/512 (b=0x6FC00000)

    0x49249249, //  0.571428571428571  i=192  0.5 / 0.5+192/512 (b=0x70000000)

    0x48FADE5C, //  0.570155902004454  i=193  0.5 / 0.5+193/512 (b=0x70400000)

    0x48D159E2, //  0.568888888888889  i=194  0.5 / 0.5+194/512 (b=0x70800000)

    0x48A8048A, //  0.567627494456763  i=195  0.5 / 0.5+195/512 (b=0x70C00000)

    0x487EDE04, //  0.566371681415929  i=196  0.5 / 0.5+196/512 (b=0x71000000)

    0x4855E601, //  0.565121412803532  i=197  0.5 / 0.5+197/512 (b=0x71400000)

    0x482D1C31, //  0.563876651982379  i=198  0.5 / 0.5+198/512 (b=0x71800000)

    0x48048048, //  0.562637362637363  i=199  0.5 / 0.5+199/512 (b=0x71C00000)

    0x47DC11F7, //  0.561403508771930  i=200  0.5 / 0.5+200/512 (b=0x72000000)

    0x47B3D0F1, //  0.560175054704595  i=201  0.5 / 0.5+201/512 (b=0x72400000)

    0x478BBCEC, //  0.558951965065502  i=202  0.5 / 0.5+202/512 (b=0x72800000)

    0x4763D59C, //  0.557734204793028  i=203  0.5 / 0.5+203/512 (b=0x72C00000)

    0x473C1AB6, //  0.556521739130435  i=204  0.5 / 0.5+204/512 (b=0x73000000)

    0x47148BF0, //  0.555314533622560  i=205  0.5 / 0.5+205/512 (b=0x73400000)

    0x46ED2901, //  0.554112554112554  i=206  0.5 / 0.5+206/512 (b=0x73800000)

    0x46C5F19F, //  0.552915766738661  i=207  0.5 / 0.5+207/512 (b=0x73C00000)

    0x469EE584, //  0.551724137931034  i=208  0.5 / 0.5+208/512 (b=0x74000000)

    0x46780467, //  0.550537634408602  i=209  0.5 / 0.5+209/512 (b=0x74400000)

    0x46514E02, //  0.549356223175966  i=210  0.5 / 0.5+210/512 (b=0x74800000)

    0x462AC20E, //  0.548179871520343  i=211  0.5 / 0.5+211/512 (b=0x74C00000)

    0x46046046, //  0.547008547008547  i=212  0.5 / 0.5+212/512 (b=0x75000000)

    0x45DE2864, //  0.545842217484009  i=213  0.5 / 0.5+213/512 (b=0x75400000)

    0x45B81A25, //  0.544680851063830  i=214  0.5 / 0.5+214/512 (b=0x75800000)

    0x45923543, //  0.543524416135881  i=215  0.5 / 0.5+215/512 (b=0x75C00000)

    0x456C797D, //  0.542372881355932  i=216  0.5 / 0.5+216/512 (b=0x76000000)

    0x4546E68F, //  0.541226215644820  i=217  0.5 / 0.5+217/512 (b=0x76400000)

    0x45217C38, //  0.540084388185654  i=218  0.5 / 0.5+218/512 (b=0x76800000)

    0x44FC3A34, //  0.538947368421053  i=219  0.5 / 0.5+219/512 (b=0x76C00000)

    0x44D72044, //  0.537815126050420  i=220  0.5 / 0.5+220/512 (b=0x77000000)

    0x44B22E27, //  0.536687631027254  i=221  0.5 / 0.5+221/512 (b=0x77400000)

    0x448D639D, //  0.535564853556485  i=222  0.5 / 0.5+222/512 (b=0x77800000)

    0x4468C066, //  0.534446764091858  i=223  0.5 / 0.5+223/512 (b=0x77C00000)

    0x44444444, //  0.533333333333333  i=224  0.5 / 0.5+224/512 (b=0x78000000)

    0x441FEEF8, //  0.532224532224532  i=225  0.5 / 0.5+225/512 (b=0x78400000)

    0x43FBC043, //  0.531120331950207  i=226  0.5 / 0.5+226/512 (b=0x78800000)

    0x43D7B7EA, //  0.530020703933747  i=227  0.5 / 0.5+227/512 (b=0x78C00000)

    0x43B3D5AF, //  0.528925619834711  i=228  0.5 / 0.5+228/512 (b=0x79000000)

    0x43901956, //  0.527835051546392  i=229  0.5 / 0.5+229/512 (b=0x79400000)

    0x436C82A2, //  0.526748971193416  i=230  0.5 / 0.5+230/512 (b=0x79800000)

    0x43491158, //  0.525667351129363  i=231  0.5 / 0.5+231/512 (b=0x79C00000)

    0x4325C53E, //  0.524590163934426  i=232  0.5 / 0.5+232/512 (b=0x7A000000)

    0x43029E1A, //  0.523517382413088  i=233  0.5 / 0.5+233/512 (b=0x7A400000)

    0x42DF9BB0, //  0.522448979591837  i=234  0.5 / 0.5+234/512 (b=0x7A800000)

    0x42BCBDC8, //  0.521384928716904  i=235  0.5 / 0.5+235/512 (b=0x7AC00000)

    0x429A0429, //  0.520325203252033  i=236  0.5 / 0.5+236/512 (b=0x7B000000)

    0x42776E9A, //  0.519269776876268  i=237  0.5 / 0.5+237/512 (b=0x7B400000)

    0x4254FCE4, //  0.518218623481781  i=238  0.5 / 0.5+238/512 (b=0x7B800000)

    0x4232AECD, //  0.517171717171717  i=239  0.5 / 0.5+239/512 (b=0x7BC00000)

    0x42108421, //  0.516129032258065  i=240  0.5 / 0.5+240/512 (b=0x7C000000)

    0x41EE7CA6, //  0.515090543259557  i=241  0.5 / 0.5+241/512 (b=0x7C400000)

    0x41CC9829, //  0.514056224899598  i=242  0.5 / 0.5+242/512 (b=0x7C800000)

    0x41AAD671, //  0.513026052104208  i=243  0.5 / 0.5+243/512 (b=0x7CC00000)

    0x4189374B, //  0.512000000000000  i=244  0.5 / 0.5+244/512 (b=0x7D000000)

    0x4167BA81, //  0.510978043912176  i=245  0.5 / 0.5+245/512 (b=0x7D400000)

    0x41465FDF, //  0.509960159362550  i=246  0.5 / 0.5+246/512 (b=0x7D800000)

    0x41252730, //  0.508946322067594  i=247  0.5 / 0.5+247/512 (b=0x7DC00000)

    0x41041041, //  0.507936507936508  i=248  0.5 / 0.5+248/512 (b=0x7E000000)

    0x40E31ADE, //  0.506930693069307  i=249  0.5 / 0.5+249/512 (b=0x7E400000)

    0x40C246D4, //  0.505928853754941  i=250  0.5 / 0.5+250/512 (b=0x7E800000)

    0x40A193F1, //  0.504930966469428  i=251  0.5 / 0.5+251/512 (b=0x7EC00000)

    0x40810204, //  0.503937007874016  i=252  0.5 / 0.5+252/512 (b=0x7F000000)

    0x406090D9, //  0.502946954813359  i=253  0.5 / 0.5+253/512 (b=0x7F400000)

    0x40404040, //  0.501960784313725  i=254  0.5 / 0.5+254/512 (b=0x7F800000)

    0x40201008  //  0.500978473581213  i=255  0.5 / 0.5+255/512 (b=0x7FC00000)

};





/*

 * Fractional multiplication of signed a and b, both in Q31. The result is doubled.

 * Note: in this test, saturation is not needed.

 * BASOP weights: 3

 */



static Word32 L_dmult( Word32 L_var1, Word32 L_var2 )

{

    Word64 L64_var1 = W_mult0_32_32( L_var1, L_var2 );

    L64_var1 = W_shr( L64_var1, 30 );

    return W_extract_l( L64_var1 );

}



/*

 * 32 by 32 bit division, following the Newton / Raphson method.

 * Usage of this low-level procedure by the caller:

 * 1. Numerator <num> can use the full range of signed 32-bit datatypes: 0x80000000...0x7FFFFFFF

 *    Note: Since <num> is not normalized here, but it is multplied to the reciprocal of the

 *    denominator, the caller should use a normalized <num> and handle any exponent outside.

 * 2. Denominator <den> must be normalized into range 0x40000001 to 0x7FFFFFFF (all positive)

 *    Note: In case of den=0x40000000, the caller is not allowed to call the division routine,

      since the result is known.

 *    Note: num / 0x40000000 equals to num with exp += 1.

 * 3. The result is in range 0x40000000 to 0x7FFFFFFF, finally multiplied by <num>.

 * BASOP weights: 24 (incl. L_dmult)

 */



Word32 div_w_newton( Word32 num, Word32 den )

{

    Word32 x0, x1, x2, x3, diff, result;



    x0 = div_w_newton_lookup[sub( extract_l( L_shr( den, 22 ) ), 256 )];

    move32();



    diff = L_sub( 0x40000000, Mpy_32_32( den, x0 ) );



    x1 = L_add( x0, L_dmult( x0, diff ) );

    diff = L_sub( 0x40000000, Mpy_32_32( den, x1 ) );



    x2 = L_add( x1, L_dmult( x1, diff ) );

    diff = L_sub( 0x40000000, Mpy_32_32( den, x2 ) );



    x3 = L_add( x2, L_dmult( x2, diff ) );



    result = Mpy_32_32( num, x3 );



    return result;

}



/*

 * 32 / 32 division

 * Usage of this global procedure by the caller:

 * 1. Numerator <num> can use the full range of signed 32-bit datatypes: 0x80000000...0x7FFFFFFF

 *    Note: Since <num> is not normalized here, but it is multplied to the reciprocal of the

 *    denominator, the caller should use a normalized <num> and handle any exponent outside.

 * 2. Denominator can use the full range of signed 32-bit datatypes: 0x80000000...0x7FFFFFFF

 *    except den=0x00000000. In case of 0x80000000, it becomes internally negated to 0x7FFFFFFF.

 * 3. The result is 0x00000000 (*s=0)for <num> equals 0x00000000.

 *    The result is rather left aligned, with up to 1 bit headroom.

 * 4. The result exponent is stored in s[0]

 * BASOP weights: 41 (incl. div_w_newton)

 */



Word32 BASOP_Util_Divide3232_Scale_newton( Word32 x, Word32 y, Word16 *s )

/*1bit HR in x > 0*/

Word32 BASOP_Util_Divide3232_Scale_cadence_1( Word32 x, Word32 y, Word16 *s )

{

    Word32 z;

    Word16 sx;

    //Word16 sx;

    Word16 sy;

    Word32 sign;



    /* assert (x >= (Word32)0); */

    assert( y != (Word32) 0 );



    /* Early exit, if numerator is zero */

    IF( x == (Word32) 0 )

    {

        *s = 0;

        return ( (Word32) 0 );

    }



#if 0

    sign = L_xor( x, y ); /* check (sign < 0) for result negation */

    sign = 0;

    move16();



    if ( x < 0 )

    {

        x = L_negate( x );

    }

#else

    IF( EQ_32( y, 0x80000000 ) )

    {

        /* Division by -1.0: same as negation of numerator */

        /* Return normalized negated numerator */

        sx = norm_l( x );

        x = L_shl( x, sx );

        *s = negate( sx );

        return L_negate( x );

    }

    sign = y;

    move32();

#endif

    if ( y < 0 )

    IF( y < 0 )

    {

        y = L_negate( y );

        sign = L_xor( sign, 1 );

    }



    /* Normalize numerator */

    sx = norm_l( x );

    x = L_shl( x, sx );



    /* Normalize denominator */

    sy = norm_l( y );

    y = L_shl( y, sy );



    /* Store exponent: + 1 for div_w_newton computing 0.5*num/den */

    *s = sub( add( sy, 1 ), sx );

    move16();

    *s = add( 0, sy );

    move16();



    /* Special treatment for den=0x40000000 */

    /* Result is known: z=2*num  */

    IF( EQ_32( y, 0x40000000 ) )

    {

        if ( sign < 0 )

        {

            x = L_negate( x );

        }

        return x;

    }



    /* Invoke division applying Newton/Raphson-Algorithm */

    z = div_w_newton( x, y );

    z = div_w( x, y );



    if ( sign < 0 )

    if ( sign != 0 )

    {

        z = L_negate( z );

    }



    return z;

}

#endif /* DIV32_OPT_NEWTON */



}

Word16 BASOP_Util_Divide3232_Scale( Word32 x, Word32 y, Word16 *s )

{

    Word16 z;

lib_com/basop_util.h

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