1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
  23  */
  24 /*
  25  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
  26  * Use is subject to license terms.
  27  */
  28 
  29 /*
  30  * __vexp: double precision vector exp
  31  *
  32  * Algorithm:
  33  *
  34  * Write x = (k + j/256)ln2 + r, where k and j are integers, j >= 0,
  35  * and |r| <= ln2/512.  Then exp(x) = 2^k * 2^(j/256) * exp(r).
  36  * Compute exp(r) by a polynomial approximation exp(r) ~ 1 + p(r)
  37  * where p(r) := r*(1+r*(B1+r*(B2+r*B3))).  From a table, obtain
  38  * h and l such that h ~ 2^(j/256) to double precision and h+l
  39  * ~ 2^(j/256) to well more than double precision.  Then exp(x)
  40  * ~ 2^k * (h + (l + h * p(r))) to about double precision.  Note
  41  * that the multiplication by 2^k requires some finagling when
  42  * the result might be subnormal.
  43  *
  44  * Accuracy:
  45  *
  46  * For normal results, the largest error observed is less than
  47  * 0.6 ulps.  For subnormal results, the largest error observed
  48  * is 0.737 ulps.
  49  */
  50 
  51 #include <sys/isa_defs.h>
  52 
  53 #ifdef _LITTLE_ENDIAN
  54 #define HI(x)   *(1+(int *)&x)
  55 #define LO(x)   *(unsigned *)&x
  56 #define DBLWORD(x, y)   y, x
  57 #else
  58 #define HI(x)   *(int *)&x
  59 #define LO(x)   *(1+(unsigned *)&x)
  60 #define DBLWORD(x, y)   x, y
  61 #endif
  62 
  63 #ifdef __RESTRICT
  64 #define restrict _Restrict
  65 #else
  66 #define restrict
  67 #endif
  68 
  69 static const double TBL[] = {
  70         1.00000000000000000000e+00,  0.00000000000000000000e+00,
  71         1.00271127505020252180e+00, -3.63661592869226394432e-17,
  72         1.00542990111280272636e+00,  9.49918653545503175702e-17,
  73         1.00815589811841754830e+00, -3.25205875608430806089e-17,
  74         1.01088928605170047526e+00, -1.52347786033685771763e-17,
  75         1.01363008495148942956e+00,  9.28359976818356758749e-18,
  76         1.01637831491095309566e+00, -5.77217007319966002766e-17,
  77         1.01913399607773791367e+00,  3.60190498225966110587e-17,
  78         1.02189714865411662714e+00,  5.10922502897344389359e-17,
  79         1.02466779289713572076e+00, -7.56160786848777820704e-17,
  80         1.02744594911876374610e+00, -4.95607417464536982418e-17,
  81         1.03023163768604097967e+00,  3.31983004108081294377e-17,
  82         1.03302487902122841490e+00,  7.60083887402708848935e-18,
  83         1.03582569360195719810e+00, -7.80678239133763616702e-17,
  84         1.03863410196137873065e+00,  5.99627378885251061843e-17,
  85         1.04145012468831610342e+00,  3.78483048028757620966e-17,
  86         1.04427378242741375480e+00,  8.55188970553796365958e-17,
  87         1.04710509587928979336e+00,  7.27707724310431474861e-17,
  88         1.04994408580068721015e+00,  5.59293784812700258637e-17,
  89         1.05279077300462642341e+00, -9.62948289902693573942e-17,
  90         1.05564517836055715705e+00,  1.75932573877209198414e-18,
  91         1.05850732279451276163e+00, -7.15265185663778073796e-17,
  92         1.06137722728926209292e+00, -1.19735370853656575649e-17,
  93         1.06425491288446449900e+00,  5.07875419861123039357e-17,
  94         1.06714040067682369717e+00, -7.89985396684158212226e-17,
  95         1.07003371182024187291e+00, -9.93716271128891938112e-17,
  96         1.07293486752597555522e+00, -3.83966884335882380671e-18,
  97         1.07584388906279104781e+00, -1.00027161511441361125e-17,
  98         1.07876079775711986031e+00, -6.65666043605659260344e-17,
  99         1.08168561499321524977e+00, -4.78262390299708626556e-17,
 100         1.08461836221330920615e+00,  3.16615284581634611576e-17,
 101         1.08755906091776965994e+00,  5.40934930782029075923e-18,
 102         1.09050773266525768967e+00, -3.04678207981247114697e-17,
 103         1.09346439907288583981e+00,  1.44139581472692093420e-17,
 104         1.09642908181637688259e+00, -5.91993348444931582405e-17,
 105         1.09940180263022191376e+00,  7.17045959970192322483e-17,
 106         1.10238258330784089090e+00,  5.26603687157069438656e-17,
 107         1.10537144570174117320e+00,  8.23928876050021358995e-17,
 108         1.10836841172367872588e+00, -8.78681384518052661558e-17,
 109         1.11137350334481754821e+00,  5.56394502666969764311e-17,
 110         1.11438674259589243221e+00,  1.04102784568455709549e-16,
 111         1.11740815156736927882e+00, -7.97680590262822045601e-17,
 112         1.12043775240960674644e+00, -6.20108590655417874998e-17,
 113         1.12347556733301989773e+00, -9.69973758898704299544e-17,
 114         1.12652161860824184814e+00,  5.16585675879545612073e-17,
 115         1.12957592856628807887e+00,  6.71280585872625658758e-17,
 116         1.13263851959871919561e+00,  3.23735616673800026374e-17,
 117         1.13570941415780546357e+00,  5.06659992612615524241e-17,
 118         1.13878863475669156458e+00,  8.91281267602540777782e-17,
 119         1.14187620396956157620e+00,  4.65109117753141238741e-17,
 120         1.14497214443180417298e+00,  4.64128989217001065651e-17,
 121         1.14807647884017893780e+00,  6.89774023662719177044e-17,
 122         1.15118922995298267331e+00,  3.25071021886382721198e-17,
 123         1.15431042059021593538e+00,  1.04171289462732661865e-16,
 124         1.15744007363375112085e+00, -9.12387123113440028710e-17,
 125         1.16057821202749877898e+00, -3.26104020541739310553e-17,
 126         1.16372485877757747552e+00,  3.82920483692409349872e-17,
 127         1.16688003695248165847e+00, -8.79187957999916974198e-17,
 128         1.17004376968325018993e+00, -1.84774420179000469438e-18,
 129         1.17321608016363732041e+00, -7.28756258658499447915e-17,
 130         1.17639699165028122074e+00,  5.55420325421807896277e-17,
 131         1.17958652746287584456e+00,  1.00923127751003904354e-16,
 132         1.18278471098434101449e+00,  1.54297543007907605845e-17,
 133         1.18599156566099384058e+00, -9.20950683529310590495e-18,
 134         1.18920711500272102690e+00,  3.98201523146564611098e-17,
 135         1.19243138258315117817e+00,  4.39755141560972082715e-17,
 136         1.19566439203982732842e+00,  4.61660367048148139743e-17,
 137         1.19890616707438057986e+00, -9.80919335600842311848e-17,
 138         1.20215673145270307565e+00,  6.64498149925230124489e-17,
 139         1.20541610900512385918e+00, -3.35727219326752963448e-17,
 140         1.20868432362658162482e+00, -4.74672594522898409739e-17,
 141         1.21196139927680124337e+00, -4.89061107752111835732e-17,
 142         1.21524735998046895524e+00, -7.71263069268148813091e-17,
 143         1.21854222982740845183e+00, -9.00672695836383767487e-17,
 144         1.22184603297275762301e+00, -1.06110212114026911612e-16,
 145         1.22515879363714552674e+00, -8.90353381426998342947e-17,
 146         1.22848053610687002468e+00, -1.89878163130252995312e-17,
 147         1.23181128473407586199e+00,  7.38938247161005024655e-17,
 148         1.23515106393693341325e+00, -1.07552443443078413783e-16,
 149         1.23849989819981654016e+00,  2.76770205557396742995e-17,
 150         1.24185781207348400201e+00,  4.65802759183693679123e-17,
 151         1.24522483017525797955e+00, -4.67724044984672750044e-17,
 152         1.24860097718920481924e+00, -8.26181099902196355046e-17,
 153         1.25198627786631622172e+00,  4.83416715246989759959e-17,
 154         1.25538075702469109629e+00, -6.71138982129687841853e-18,
 155         1.25878443954971652730e+00, -8.42178258773059935677e-17,
 156         1.26219735039425073886e+00, -3.08446488747384584900e-17,
 157         1.26561951457880628169e+00,  4.25057700345086802072e-17,
 158         1.26905095719173321989e+00,  2.66793213134218609523e-18,
 159         1.27249170338940276181e+00, -1.05779162672124210291e-17,
 160         1.27594177839639200123e+00,  9.91543024421429032951e-17,
 161         1.27940120750566932450e+00, -9.75909500835606221035e-17,
 162         1.28287001607877826359e+00,  1.71359491824356096814e-17,
 163         1.28634822954602556777e+00, -3.41695570693618197638e-17,
 164         1.28983587340666572274e+00,  8.94925753089759172195e-17,
 165         1.29333297322908946647e+00, -2.97459044313275164581e-17,
 166         1.29683955465100964055e+00,  2.53825027948883149593e-17,
 167         1.30035564337965059423e+00,  5.67872810280221742200e-17,
 168         1.30388126519193581210e+00,  8.64767559826787117946e-17,
 169         1.30741644593467731816e+00, -7.33664565287886889230e-17,
 170         1.31096121152476441374e+00, -7.18153613551945385697e-17,
 171         1.31451558794935463581e+00,  2.26754331510458564505e-17,
 172         1.31807960126606404927e+00, -5.45795582714915288619e-17,
 173         1.32165327760315753913e+00, -2.48063824591302174150e-17,
 174         1.32523664315974132322e+00, -2.85873121003886075697e-17,
 175         1.32882972420595435459e+00,  4.08908622391016005195e-17,
 176         1.33243254708316150037e+00, -5.10158663091674334319e-17,
 177         1.33604513820414583236e+00, -5.89186635638880135250e-17,
 178         1.33966752405330291609e+00,  8.92728259483173198426e-17,
 179         1.34329973118683532185e+00, -5.80258089020143775130e-17,
 180         1.34694178623294580355e+00,  3.22406510125467916913e-17,
 181         1.35059371589203447428e+00, -8.28711038146241653260e-17,
 182         1.35425554693689265129e+00,  7.70094837980298946162e-17,
 183         1.35792730621290114179e+00, -9.52963574482518886709e-17,
 184         1.36160902063822475405e+00,  1.53378766127066804593e-18,
 185         1.36530071720401191548e+00, -1.00053631259747639350e-16,
 186         1.36900242297459051599e+00,  9.59379791911884877256e-17,
 187         1.37271416508766841424e+00, -4.49596059523484126201e-17,
 188         1.37643597075453016920e+00, -6.89858893587180104162e-17,
 189         1.38016786726023799048e+00,  1.05103145799699839462e-16,
 190         1.38390988196383202258e+00, -6.77051165879478628716e-17,
 191         1.38766204229852907481e+00,  8.42298427487541531762e-17,
 192         1.39142437577192623621e+00, -4.90617486528898870821e-17,
 193         1.39519690996620027157e+00, -9.32933622422549531960e-17,
 194         1.39897967253831123635e+00, -9.61421320905132307233e-17,
 195         1.40277269122020475933e+00, -5.29578324940798922316e-17,
 196         1.40657599381901543545e+00,  7.03491481213642218800e-18,
 197         1.41038960821727066275e+00,  4.16654872843506164270e-17,
 198         1.41421356237309514547e+00, -9.66729331345291345105e-17,
 199         1.41804788432041517510e+00,  2.27443854218552945230e-17,
 200         1.42189260216916557589e+00, -1.60778289158902441338e-17,
 201         1.42574774410549420800e+00,  9.88069075850060728430e-17,
 202         1.42961333839197002327e+00, -1.20316424890536551792e-17,
 203         1.43348941336778890054e+00, -5.80245424392682610310e-17,
 204         1.43737599744898236764e+00, -4.20403401646755661225e-17,
 205         1.44127311912862565713e+00,  5.60250365087898567501e-18,
 206         1.44518080697704665027e+00, -3.02375813499398731940e-17,
 207         1.44909908964203504311e+00, -6.25940500081930925441e-17,
 208         1.45302799584905262265e+00, -5.77994860939610610226e-17,
 209         1.45696755440144376514e+00,  5.64867945387699814049e-17,
 210         1.46091779418064704466e+00, -5.60037718607521580013e-17,
 211         1.46487874414640573129e+00,  9.53076754358715731900e-17,
 212         1.46885043333698184220e+00,  8.46588275653362637570e-17,
 213         1.47283289086936752810e+00,  6.69177408194058937165e-17,
 214         1.47682614593949934623e+00, -3.48399455689279579579e-17,
 215         1.48083022782247186733e+00, -9.68695210263061857841e-17,
 216         1.48484516587275239274e+00,  1.07800867644074807559e-16,
 217         1.48887098952439700383e+00,  6.15536715774287133031e-17,
 218         1.49290772829126483501e+00,  1.41929201542840357707e-17,
 219         1.49695541176723545540e+00, -2.86166325389915821109e-17,
 220         1.50101406962642558440e+00, -6.41376727579023503859e-17,
 221         1.50508373162340647333e+00,  7.07471061358284636429e-17,
 222         1.50916442759342284141e+00, -1.01645532775429503911e-16,
 223         1.51325618745260981335e+00,  8.88449785133871209093e-17,
 224         1.51735904119821474190e+00, -4.30869947204334080070e-17,
 225         1.52147301890881458952e+00, -5.99638767594568341985e-18,
 226         1.52559815074453819506e+00,  1.11795187801605698722e-16,
 227         1.52973446694728698603e+00,  3.78579211515721903683e-17,
 228         1.53388199784095591305e+00,  8.87522684443844614135e-17,
 229         1.53804077383165682669e+00,  1.01746723511613580618e-16,
 230         1.54221082540794074411e+00,  7.94983480969762085616e-17,
 231         1.54639218314102144802e+00,  1.06839600056572198028e-16,
 232         1.55058487768499997372e+00, -1.46007065906893851791e-17,
 233         1.55478893977708865215e+00, -8.00316135011603564104e-17,
 234         1.55900440023783692922e+00,  3.78120705335752750188e-17,
 235         1.56323128997135762930e+00,  7.48477764559073438896e-17,
 236         1.56746963996555299659e+00, -1.03520617688497219883e-16,
 237         1.57171948129234140268e+00, -3.34298400468720006928e-17,
 238         1.57598084510788649659e+00, -1.01369164712783039808e-17,
 239         1.58025376265282457844e+00, -5.16340292955446806159e-17,
 240         1.58453826525249374946e+00, -1.93377170345857029304e-17,
 241         1.58883438431716395023e+00, -5.99495011882447940052e-18,
 242         1.59314215134226699888e+00, -1.00944065423119624890e-16,
 243         1.59746159790862707339e+00,  2.48683927962209992069e-17,
 244         1.60179275568269341434e+00, -6.05491745352778434252e-17,
 245         1.60613565641677102924e+00, -1.03545452880599952591e-16,
 246         1.61049033194925428347e+00,  2.47071925697978878522e-17,
 247         1.61485681420486071325e+00, -7.31666339912512326264e-17,
 248         1.61923513519486372836e+00,  2.09413341542290924068e-17,
 249         1.62362532701732886764e+00, -3.58451285141447470996e-17,
 250         1.62802742185734783398e+00, -6.71295508470708408630e-17,
 251         1.63244145198727497181e+00,  9.85281923042999296414e-17,
 252         1.63686744976696441078e+00,  7.69832507131987557450e-17,
 253         1.64130544764400632118e+00, -9.24756873764070550805e-17,
 254         1.64575547815396494578e+00, -1.01256799136747726038e-16,
 255         1.65021757392061774183e+00,  9.13327958872990419009e-18,
 256         1.65469176765619430114e+00,  9.64329430319602742879e-17,
 257         1.65917809216161615815e+00, -7.27554555082304942180e-17,
 258         1.66367658032673637614e+00,  5.89099269671309967045e-17,
 259         1.66818726513058246397e+00,  4.26917801957061447430e-17,
 260         1.67271017964159662839e+00, -5.47671596459956307616e-17,
 261         1.67724535701787846875e+00,  8.30394950995073155275e-17,
 262         1.68179283050742900407e+00,  8.19901002058149652013e-17,
 263         1.68635263344839336774e+00, -7.18146327835800944212e-17,
 264         1.69092479926930527867e+00, -9.66967147439488016590e-17,
 265         1.69550936148933262260e+00,  7.23841687284516664081e-17,
 266         1.70010635371852347753e+00, -8.02371937039770024589e-18,
 267         1.70471580965805125096e+00, -2.72888328479728156257e-17,
 268         1.70933776310046292579e+00, -9.86877945663293107628e-17,
 269         1.71397224792992597386e+00,  6.47397510775336706412e-17,
 270         1.71861929812247793414e+00, -1.85138041826311098821e-17,
 271         1.72327894774627399244e+00, -9.52212380039379996275e-17,
 272         1.72795123096183766975e+00, -1.07509818612046424459e-16,
 273         1.73263618202231106658e+00, -1.69805107431541549407e-18,
 274         1.73733383527370621735e+00,  3.16438929929295694659e-17,
 275         1.74204422515515644498e+00, -1.52595911895078879236e-18,
 276         1.74676738619916904760e+00, -1.07522904835075145042e-16,
 277         1.75150335303187820735e+00, -5.12445042059672465939e-17,
 278         1.75625216037329945351e+00,  2.96014069544887330703e-17,
 279         1.76101384303758390359e+00, -7.94325312503922771057e-17,
 280         1.76578843593327272643e+00,  9.46131501808326786660e-17,
 281         1.77057597406355471392e+00,  5.96179451004055584767e-17,
 282         1.77537649252652118825e+00,  6.42973179655657203396e-17,
 283         1.78019002651542446181e+00, -5.28462728909161736517e-17,
 284         1.78501661131893496481e+00,  1.53304001210313138184e-17,
 285         1.78985628232140103755e+00, -4.15435466068334977098e-17,
 286         1.79470907500310716820e+00,  1.82274584279120867698e-17,
 287         1.79957502494053511732e+00, -2.52688923335889795224e-17,
 288         1.80445416780662393208e+00, -5.17722240879331788328e-17,
 289         1.80934653937103195886e+00, -9.03264140245002968190e-17,
 290         1.81425217550039885595e+00, -9.96953153892034881983e-17,
 291         1.81917111215860849427e+00,  7.40267690114583888997e-17,
 292         1.82410338540705341259e+00, -1.01596278622770830650e-16,
 293         1.82904903140489727420e+00,  6.88919290883569563697e-17,
 294         1.83400808640934243066e+00,  3.28310722424562658722e-17,
 295         1.83898058677589371079e+00,  6.91896974027251194233e-18,
 296         1.84396656895862598446e+00, -5.93974202694996455028e-17,
 297         1.84896606951045083811e+00,  9.02758044626108928816e-17,
 298         1.85397912508338547077e+00,  9.76188749072759353840e-17,
 299         1.85900577242882047990e+00, -9.52870546198994068663e-17,
 300         1.86404604839778897940e+00,  6.54091268062057047791e-17,
 301         1.86909998994123860427e+00, -9.93850521425506708290e-17,
 302         1.87416763411029996256e+00, -6.12276341300414256164e-17,
 303         1.87924901805656019427e+00, -1.62263155578358447799e-17,
 304         1.88434417903233453195e+00, -8.22659312553371090551e-17,
 305         1.88945315439093919352e+00, -9.00516828505912548531e-17,
 306         1.89457598158696560731e+00,  3.40340353521652967060e-17,
 307         1.89971269817655530332e+00, -3.85973976937851370678e-17,
 308         1.90486334181767413831e+00,  6.53385751471827862895e-17,
 309         1.91002795027038985154e+00, -5.90968800674406023686e-17,
 310         1.91520656139714740007e+00, -1.06199460561959626376e-16,
 311         1.92039921316304740273e+00,  7.11668154063031418621e-17,
 312         1.92560594363612502811e+00, -9.91496376969374092749e-17,
 313         1.93082679098762710623e+00,  6.16714970616910955284e-17,
 314         1.93606179349229434727e+00,  1.03323859606763257448e-16,
 315         1.94131098952864045160e+00, -6.63802989162148798984e-17,
 316         1.94657441757923321823e+00,  6.81102234953387718436e-17,
 317         1.95185211623097831790e+00, -2.19901696997935108603e-17,
 318         1.95714412417540017941e+00,  8.96076779103666776760e-17,
 319         1.96245048020892731699e+00,  1.09768440009135469493e-16,
 320         1.96777122323317588126e+00, -1.03149280115311315109e-16,
 321         1.97310639225523432039e+00, -7.45161786395603748608e-18,
 322         1.97845602638795092787e+00,  4.03887531092781665750e-17,
 323         1.98382016485021939189e+00, -2.20345441239106265716e-17,
 324         1.98919884696726634310e+00,  8.20513263836919941553e-18,
 325         1.99459211217094023461e+00,  1.79097103520026450854e-17
 326 };
 327 
 328 static const union {
 329         unsigned        i[2];
 330         double          d;
 331 } C[] = {
 332         { DBLWORD(0x43380000, 0x00000000) },
 333         { DBLWORD(0x40771547, 0x652b82fe) },
 334         { DBLWORD(0x3f662e42, 0xfee00000) },
 335         { DBLWORD(0x3d6a39ef, 0x35793c76) },
 336         { DBLWORD(0x3ff00000, 0x00000000) },
 337         { DBLWORD(0x3fdfffff, 0xfffffff6) },
 338         { DBLWORD(0x3fc55555, 0x721a1d14) },
 339         { DBLWORD(0x3fa55555, 0x6e0896af) },
 340         { DBLWORD(0x01000000, 0x00000000) },
 341         { DBLWORD(0x7f000000, 0x00000000) },
 342         { DBLWORD(0x40862e42, 0xfefa39ef) },
 343         { DBLWORD(0xc0874910, 0xd52d3051) },
 344         { DBLWORD(0xfff00000, 0x00000000) },
 345         { DBLWORD(0x00000000, 0x00000000) }
 346 };
 347 
 348 #define round           C[0].d
 349 #define invln2_256      C[1].d
 350 #define ln2_256h        C[2].d
 351 #define ln2_256l        C[3].d
 352 #define one             C[4].d
 353 #define B1              C[5].d
 354 #define B2              C[6].d
 355 #define B3              C[7].d
 356 #define tiny            C[8].d
 357 #define huge            C[9].d
 358 #define othresh         C[10].d
 359 #define uthresh         C[11].d
 360 #define neginf          C[12].d
 361 #define zero            C[13].d
 362 
 363 #define PROCESS(N)                                              \
 364         y##N = (x##N * invln2_256) + round;                     \
 365         j##N = LO(y##N);                                        \
 366         y##N -= round;                                          \
 367         k##N = j##N >> 8;                                 \
 368         j##N = (j##N & 0xff) << 1;                            \
 369         x##N = (x##N - y##N * ln2_256h) - y##N * ln2_256l;      \
 370         y##N = x##N * (one + x##N * (B1 + x##N * (B2 + x##N * B3)));    \
 371         t##N = TBL[j##N];                                       \
 372         y##N = t##N + (TBL[j##N + 1] + t##N * y##N);            \
 373         if (k##N < -1021) {                                  \
 374                 HI(y##N) += (k##N + 0x3ef) << 20;         \
 375                 y##N *= tiny;                                   \
 376         } else {                                                \
 377                 HI(y##N) += k##N << 20;                           \
 378         }                                                       \
 379         *y = y##N;                                              \
 380         y += stridey
 381 
 382 #define PREPROCESS(N, index, label)                             \
 383         hx = HI(x[0]);                                          \
 384         ix = hx & ~0x80000000;                                      \
 385         x##N = *x;                                              \
 386         x += stridex;                                           \
 387         if (ix >= 0x40862e42) {                                      \
 388                 if (ix >= 0x7ff00000) { /* x is inf or nan */        \
 389                         y[index] = (x##N == neginf)? zero :     \
 390                             x##N * x##N;                        \
 391                         goto label;                             \
 392                 }                                               \
 393                 if (x##N > othresh) {                                \
 394                         y[index] = huge * huge;                 \
 395                         goto label;                             \
 396                 }                                               \
 397                 if (x##N < uthresh) {                                \
 398                         y[index] = tiny * tiny;                 \
 399                         goto label;                             \
 400                 }                                               \
 401         } else if (ix < 0x3e300000) { /* |x| < 2^-28 */           \
 402                 y[index] = one + x##N;                          \
 403                 goto label;                                     \
 404         }
 405 
 406 void
 407 __vexp(int n, double *restrict x, int stridex, double *restrict y,
 408     int stridey)
 409 {
 410         double          x0, x1, x2, x3, x4, x5;
 411         double          y0, y1, y2, y3, y4, y5;
 412         double          t0, t1, t2, t3, t4, t5;
 413         int             k0, k1, k2, k3, k4, k5;
 414         int             j0, j1, j2, j3, j4, j5;
 415         int             hx, ix;
 416 
 417         y -= stridey;
 418 
 419         for (;;) {
 420 begin:
 421                 if (--n < 0)
 422                         break;
 423                 y += stridey;
 424 
 425                 PREPROCESS(0, 0, begin);
 426 
 427                 if (--n < 0)
 428                         goto process1;
 429 
 430                 PREPROCESS(1, stridey, process1);
 431 
 432                 if (--n < 0)
 433                         goto process2;
 434 
 435                 PREPROCESS(2, stridey << 1, process2);
 436 
 437                 if (--n < 0)
 438                         goto process3;
 439 
 440                 PREPROCESS(3, (stridey << 1) + stridey, process3);
 441 
 442                 if (--n < 0)
 443                         goto process4;
 444 
 445                 PREPROCESS(4, stridey << 2, process4);
 446 
 447                 if (--n < 0)
 448                         goto process5;
 449 
 450                 PREPROCESS(5, (stridey << 2) + stridey, process5);
 451 
 452                 y0 = (x0 * invln2_256) + round;
 453                 y1 = (x1 * invln2_256) + round;
 454                 y2 = (x2 * invln2_256) + round;
 455                 y3 = (x3 * invln2_256) + round;
 456                 y4 = (x4 * invln2_256) + round;
 457                 y5 = (x5 * invln2_256) + round;
 458 
 459                 j0 = LO(y0);
 460                 j1 = LO(y1);
 461                 j2 = LO(y2);
 462                 j3 = LO(y3);
 463                 j4 = LO(y4);
 464                 j5 = LO(y5);
 465 
 466                 y0 -= round;
 467                 y1 -= round;
 468                 y2 -= round;
 469                 y3 -= round;
 470                 y4 -= round;
 471                 y5 -= round;
 472 
 473                 k0 = j0 >> 8;
 474                 k1 = j1 >> 8;
 475                 k2 = j2 >> 8;
 476                 k3 = j3 >> 8;
 477                 k4 = j4 >> 8;
 478                 k5 = j5 >> 8;
 479 
 480                 j0 = (j0 & 0xff) << 1;
 481                 j1 = (j1 & 0xff) << 1;
 482                 j2 = (j2 & 0xff) << 1;
 483                 j3 = (j3 & 0xff) << 1;
 484                 j4 = (j4 & 0xff) << 1;
 485                 j5 = (j5 & 0xff) << 1;
 486 
 487                 x0 = (x0 - y0 * ln2_256h) - y0 * ln2_256l;
 488                 x1 = (x1 - y1 * ln2_256h) - y1 * ln2_256l;
 489                 x2 = (x2 - y2 * ln2_256h) - y2 * ln2_256l;
 490                 x3 = (x3 - y3 * ln2_256h) - y3 * ln2_256l;
 491                 x4 = (x4 - y4 * ln2_256h) - y4 * ln2_256l;
 492                 x5 = (x5 - y5 * ln2_256h) - y5 * ln2_256l;
 493 
 494                 y0 = x0 * (one + x0 * (B1 + x0 * (B2 + x0 * B3)));
 495                 y1 = x1 * (one + x1 * (B1 + x1 * (B2 + x1 * B3)));
 496                 y2 = x2 * (one + x2 * (B1 + x2 * (B2 + x2 * B3)));
 497                 y3 = x3 * (one + x3 * (B1 + x3 * (B2 + x3 * B3)));
 498                 y4 = x4 * (one + x4 * (B1 + x4 * (B2 + x4 * B3)));
 499                 y5 = x5 * (one + x5 * (B1 + x5 * (B2 + x5 * B3)));
 500 
 501                 t0 = TBL[j0];
 502                 t1 = TBL[j1];
 503                 t2 = TBL[j2];
 504                 t3 = TBL[j3];
 505                 t4 = TBL[j4];
 506                 t5 = TBL[j5];
 507 
 508                 y0 = t0 + (TBL[j0 + 1] + t0 * y0);
 509                 y1 = t1 + (TBL[j1 + 1] + t1 * y1);
 510                 y2 = t2 + (TBL[j2 + 1] + t2 * y2);
 511                 y3 = t3 + (TBL[j3 + 1] + t3 * y3);
 512                 y4 = t4 + (TBL[j4 + 1] + t4 * y4);
 513                 y5 = t5 + (TBL[j5 + 1] + t5 * y5);
 514 
 515                 if (k0 < -1021) {
 516                         HI(y0) += (k0 + 0x3ef) << 20;
 517                         y0 *= tiny;
 518                 } else {
 519                         HI(y0) += k0 << 20;
 520                 }
 521                 if (k1 < -1021) {
 522                         HI(y1) += (k1 + 0x3ef) << 20;
 523                         y1 *= tiny;
 524                 } else {
 525                         HI(y1) += k1 << 20;
 526                 }
 527                 if (k2 < -1021) {
 528                         HI(y2) += (k2 + 0x3ef) << 20;
 529                         y2 *= tiny;
 530                 } else {
 531                         HI(y2) += k2 << 20;
 532                 }
 533                 if (k3 < -1021) {
 534                         HI(y3) += (k3 + 0x3ef) << 20;
 535                         y3 *= tiny;
 536                 } else {
 537                         HI(y3) += k3 << 20;
 538                 }
 539                 if (k4 < -1021) {
 540                         HI(y4) += (k4 + 0x3ef) << 20;
 541                         y4 *= tiny;
 542                 } else {
 543                         HI(y4) += k4 << 20;
 544                 }
 545                 if (k5 < -1021) {
 546                         HI(y5) += (k5 + 0x3ef) << 20;
 547                         y5 *= tiny;
 548                 } else {
 549                         HI(y5) += k5 << 20;
 550                 }
 551 
 552                 y[0] = y0;
 553                 y[stridey] = y1;
 554                 y[stridey << 1] = y2;
 555                 y[(stridey << 1) + stridey] = y3;
 556                 y[stridey << 2] = y4;
 557                 y[(stridey << 2) + stridey] = y5;
 558                 y += (stridey << 2) + stridey;
 559                 continue;
 560 
 561 process1:
 562                 PROCESS(0);
 563                 continue;
 564 
 565 process2:
 566                 PROCESS(0);
 567                 PROCESS(1);
 568                 continue;
 569 
 570 process3:
 571                 PROCESS(0);
 572                 PROCESS(1);
 573                 PROCESS(2);
 574                 continue;
 575 
 576 process4:
 577                 PROCESS(0);
 578                 PROCESS(1);
 579                 PROCESS(2);
 580                 PROCESS(3);
 581                 continue;
 582 
 583 process5:
 584                 PROCESS(0);
 585                 PROCESS(1);
 586                 PROCESS(2);
 587                 PROCESS(3);
 588                 PROCESS(4);
 589         }
 590 }