From 483b5e23cb9adadb8d4e155292e01ecbdb365b56 Mon Sep 17 00:00:00 2001 From: Julius Pfrommer Date: Sat, 9 Nov 2024 20:33:49 +0100 Subject: [PATCH] refactor(deps): Internallize strtod (using the ryu2 code) --- CMakeLists.txt | 1 + deps/README.md | 1 + deps/parse_num.c | 18 -- deps/strtod.c | 675 +++++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 677 insertions(+), 18 deletions(-) create mode 100644 deps/strtod.c diff --git a/CMakeLists.txt b/CMakeLists.txt index 001e094c2ef..6ac8030389c 100644 --- a/CMakeLists.txt +++ b/CMakeLists.txt @@ -848,6 +848,7 @@ if(UA_ENABLE_JSON_ENCODING) ${PROJECT_SOURCE_DIR}/src/ua_types_encoding_json.h) list(APPEND lib_sources ${PROJECT_SOURCE_DIR}/deps/cj5.c ${PROJECT_SOURCE_DIR}/deps/parse_num.c + ${PROJECT_SOURCE_DIR}/deps/strtod.c ${PROJECT_SOURCE_DIR}/src/ua_types_encoding_json.c ${PROJECT_SOURCE_DIR}/src/pubsub/ua_pubsub_networkmessage_json.c) endif() diff --git a/deps/README.md b/deps/README.md index e47742bb7ae..473461f17a5 100644 --- a/deps/README.md +++ b/deps/README.md @@ -20,4 +20,5 @@ The following third party libraries may be included -- depending on the activate | ziptree | MPL 2.0 | Reusable zip tree implementation | | mqtt-c | MIT | a portable MQTT client in C | | dtoa | BSL (Boost) | Printing of float numbers | +| strtod | BSL (Boost) | Parsing of float numbers | | mp_printf | MIT | Our version of github:mpaland/printf | diff --git a/deps/parse_num.c b/deps/parse_num.c index 0fa2919b1d6..d2d57bc4557 100644 --- a/deps/parse_num.c +++ b/deps/parse_num.c @@ -22,10 +22,6 @@ #include "parse_num.h" -#include -#include -#include - size_t parseUInt64(const char *str, size_t size, uint64_t *result) { size_t i = 0; @@ -95,17 +91,3 @@ parseInt64(const char *str, size_t size, int64_t *result) { } return len + i; } - -size_t parseDouble(const char *str, size_t size, double *result) { - char buf[2000]; - if(size >= 2000) - return 0; - memcpy(buf, str, size); - buf[size] = 0; - errno = 0; - char *endptr; - *result = strtod(str, &endptr); - if(errno != 0 && errno != ERANGE) - return 0; - return (uintptr_t)endptr - (uintptr_t)str; -} diff --git a/deps/strtod.c b/deps/strtod.c new file mode 100644 index 00000000000..5338d38fb9b --- /dev/null +++ b/deps/strtod.c @@ -0,0 +1,675 @@ +// Copyright 2010 Ulf Adams +// Copyright 2024 Julius Pfrommer +// +// Taken from https://github.com/ulfjack/ryu +// +// Boost Software License - Version 1.0 - August 17th, 2003 +// +// Permission is hereby granted, free of charge, to any person or organization +// obtaining a copy of the software and accompanying documentation covered by +// this license (the "Software") to use, reproduce, display, distribute, +// execute, and transmit the Software, and to prepare derivative works of the +// Software, and to permit third-parties to whom the Software is furnished to +// do so, all subject to the following: +// +// The copyright notices in the Software and this entire statement, including +// the above license grant, this restriction and the following disclaimer, +// must be included in all copies of the Software, in whole or in part, and +// all derivative works of the Software, unless such copies or derivative +// works are solely in the form of machine-executable object code generated by +// a source language processor. +// +// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +// FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT +// SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE +// FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE, +// ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER +// DEALINGS IN THE SOFTWARE. + +#include "parse_num.h" +#include +#include +#include + +#define DOUBLE_MANTISSA_BITS 52 +#define DOUBLE_EXPONENT_BITS 11 +#define DOUBLE_EXPONENT_BIAS 1023 + +#define DOUBLE_POW5_INV_BITCOUNT 125 +#define DOUBLE_POW5_BITCOUNT 125 + +#define DOUBLE_POW5_INV_TABLE_SIZE 342 +#define DOUBLE_POW5_TABLE_SIZE 326 + +static const uint64_t DOUBLE_POW5_INV_SPLIT[DOUBLE_POW5_INV_TABLE_SIZE][2] = { + { 1u, 2305843009213693952u }, { 11068046444225730970u, 1844674407370955161u }, + { 5165088340638674453u, 1475739525896764129u }, { 7821419487252849886u, 1180591620717411303u }, + { 8824922364862649494u, 1888946593147858085u }, { 7059937891890119595u, 1511157274518286468u }, + { 13026647942995916322u, 1208925819614629174u }, 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8411165935146048523u, 1295374421166787957u }, + { 17147214310975587960u, 2072599073866860731u }, { 10028422634038560045u, 1658079259093488585u }, + { 8022738107230848036u, 1326463407274790868u }, { 9147032156827446534u, 2122341451639665389u }, + { 11006974540203867551u, 1697873161311732311u }, { 5116230817421183718u, 1358298529049385849u }, + { 15564666937357714594u, 2173277646479017358u }, { 1383687105660440706u, 1738622117183213887u }, + { 12174996128754083534u, 1390897693746571109u }, { 8411947361780802685u, 2225436309994513775u }, + { 6729557889424642148u, 1780349047995611020u }, { 5383646311539713719u, 1424279238396488816u }, + { 1235136468979721303u, 2278846781434382106u }, { 15745504434151418335u, 1823077425147505684u }, + { 16285752362063044992u, 1458461940118004547u }, { 5649904260166615347u, 1166769552094403638u }, + { 5350498001524674232u, 1866831283351045821u }, { 591049586477829062u, 1493465026680836657u }, + { 11540886113407994219u, 1194772021344669325u }, { 18673707743239135u, 1911635234151470921u }, + { 14772334225162232601u, 1529308187321176736u }, { 8128518565387875758u, 1223446549856941389u }, + { 1937583260394870242u, 1957514479771106223u }, { 8928764237799716840u, 1566011583816884978u }, + { 14521709019723594119u, 1252809267053507982u }, { 8477339172590109297u, 2004494827285612772u }, + { 17849917782297818407u, 1603595861828490217u }, { 6901236596354434079u, 1282876689462792174u }, + { 18420676183650915173u, 2052602703140467478u }, { 3668494502695001169u, 1642082162512373983u }, + { 10313493231639821582u, 1313665730009899186u }, { 9122891541139893884u, 2101865168015838698u }, + { 14677010862395735754u, 1681492134412670958u }, { 673562245690857633u, 1345193707530136767u } +}; + +static const uint64_t DOUBLE_POW5_SPLIT[DOUBLE_POW5_TABLE_SIZE][2] = { + { 0u, 1152921504606846976u }, { 0u, 1441151880758558720u }, + { 0u, 1801439850948198400u }, { 0u, 2251799813685248000u }, + { 0u, 1407374883553280000u }, { 0u, 1759218604441600000u }, + { 0u, 2199023255552000000u }, { 0u, 1374389534720000000u }, + { 0u, 1717986918400000000u }, { 0u, 2147483648000000000u }, + { 0u, 1342177280000000000u }, { 0u, 1677721600000000000u }, + { 0u, 2097152000000000000u }, { 0u, 1310720000000000000u }, + { 0u, 1638400000000000000u }, { 0u, 2048000000000000000u }, + { 0u, 1280000000000000000u }, { 0u, 1600000000000000000u }, + { 0u, 2000000000000000000u }, { 0u, 1250000000000000000u }, + { 0u, 1562500000000000000u }, { 0u, 1953125000000000000u }, + { 0u, 1220703125000000000u }, { 0u, 1525878906250000000u }, + { 0u, 1907348632812500000u }, { 0u, 1192092895507812500u }, + { 0u, 1490116119384765625u }, { 4611686018427387904u, 1862645149230957031u }, + { 9799832789158199296u, 1164153218269348144u }, { 12249790986447749120u, 1455191522836685180u }, + { 15312238733059686400u, 1818989403545856475u }, { 14528612397897220096u, 2273736754432320594u }, + { 13692068767113150464u, 1421085471520200371u }, { 12503399940464050176u, 1776356839400250464u }, + { 15629249925580062720u, 2220446049250313080u }, { 9768281203487539200u, 1387778780781445675u }, + { 7598665485932036096u, 1734723475976807094u }, { 274959820560269312u, 2168404344971008868u }, + { 9395221924704944128u, 1355252715606880542u }, { 2520655369026404352u, 1694065894508600678u }, + { 12374191248137781248u, 2117582368135750847u }, { 14651398557727195136u, 1323488980084844279u }, + { 13702562178731606016u, 1654361225106055349u }, { 3293144668132343808u, 2067951531382569187u }, + { 18199116482078572544u, 1292469707114105741u }, { 8913837547316051968u, 1615587133892632177u }, + { 15753982952572452864u, 2019483917365790221u }, { 12152082354571476992u, 1262177448353618888u }, + { 15190102943214346240u, 1577721810442023610u }, { 9764256642163156992u, 1972152263052529513u }, + { 17631875447420442880u, 1232595164407830945u }, { 8204786253993389888u, 1540743955509788682u }, + { 1032610780636961552u, 1925929944387235853u }, { 2951224747111794922u, 1203706215242022408u }, + { 3689030933889743652u, 1504632769052528010u }, { 13834660704216955373u, 1880790961315660012u }, + { 17870034976990372916u, 1175494350822287507u }, { 17725857702810578241u, 1469367938527859384u }, + { 3710578054803671186u, 1836709923159824231u }, { 26536550077201078u, 2295887403949780289u }, + { 11545800389866720434u, 1434929627468612680u }, { 14432250487333400542u, 1793662034335765850u }, + { 8816941072311974870u, 2242077542919707313u }, { 17039803216263454053u, 1401298464324817070u }, + { 12076381983474541759u, 1751623080406021338u }, { 5872105442488401391u, 2189528850507526673u }, + { 15199280947623720629u, 1368455531567204170u }, { 9775729147674874978u, 1710569414459005213u }, + { 16831347453020981627u, 2138211768073756516u }, { 1296220121283337709u, 1336382355046097823u }, + { 15455333206886335848u, 1670477943807622278u }, { 10095794471753144002u, 2088097429759527848u }, + { 6309871544845715001u, 1305060893599704905u }, { 12499025449484531656u, 1631326116999631131u }, + { 11012095793428276666u, 2039157646249538914u }, { 11494245889320060820u, 1274473528905961821u }, + { 532749306367912313u, 1593091911132452277u }, { 5277622651387278295u, 1991364888915565346u }, + { 7910200175544436838u, 1244603055572228341u }, { 14499436237857933952u, 1555753819465285426u }, + { 8900923260467641632u, 1944692274331606783u }, { 12480606065433357876u, 1215432671457254239u }, + { 10989071563364309441u, 1519290839321567799u }, { 9124653435777998898u, 1899113549151959749u }, + { 8008751406574943263u, 1186945968219974843u }, { 5399253239791291175u, 1483682460274968554u }, + { 15972438586593889776u, 1854603075343710692u }, { 759402079766405302u, 1159126922089819183u }, + { 14784310654990170340u, 1448908652612273978u }, { 9257016281882937117u, 1811135815765342473u }, + { 16182956370781059300u, 2263919769706678091u }, { 7808504722524468110u, 1414949856066673807u }, + { 5148944884728197234u, 1768687320083342259u }, { 1824495087482858639u, 2210859150104177824u }, + { 1140309429676786649u, 1381786968815111140u }, { 1425386787095983311u, 1727233711018888925u }, + { 6393419502297367043u, 2159042138773611156u }, { 13219259225790630210u, 1349401336733506972u }, + { 16524074032238287762u, 1686751670916883715u }, { 16043406521870471799u, 2108439588646104644u }, + { 803757039314269066u, 1317774742903815403u }, { 14839754354425000045u, 1647218428629769253u }, + { 4714634887749086344u, 2059023035787211567u }, { 9864175832484260821u, 1286889397367007229u }, + { 16941905809032713930u, 1608611746708759036u }, { 2730638187581340797u, 2010764683385948796u }, + { 10930020904093113806u, 1256727927116217997u }, { 18274212148543780162u, 1570909908895272496u }, + { 4396021111970173586u, 1963637386119090621u }, { 5053356204195052443u, 1227273366324431638u }, + { 15540067292098591362u, 1534091707905539547u }, { 14813398096695851299u, 1917614634881924434u }, + { 13870059828862294966u, 1198509146801202771u }, { 12725888767650480803u, 1498136433501503464u }, + { 15907360959563101004u, 1872670541876879330u }, { 14553786618154326031u, 1170419088673049581u }, + { 4357175217410743827u, 1463023860841311977u }, { 10058155040190817688u, 1828779826051639971u }, + { 7961007781811134206u, 2285974782564549964u }, { 14199001900486734687u, 1428734239102843727u }, + { 13137066357181030455u, 1785917798878554659u }, { 11809646928048900164u, 2232397248598193324u }, + { 16604401366885338411u, 1395248280373870827u }, { 16143815690179285109u, 1744060350467338534u }, + { 10956397575869330579u, 2180075438084173168u }, { 6847748484918331612u, 1362547148802608230u }, + { 17783057643002690323u, 1703183936003260287u }, { 17617136035325974999u, 2128979920004075359u }, + { 17928239049719816230u, 1330612450002547099u }, { 17798612793722382384u, 1663265562503183874u }, + { 13024893955298202172u, 2079081953128979843u }, { 5834715712847682405u, 1299426220705612402u }, + { 16516766677914378815u, 1624282775882015502u }, { 11422586310538197711u, 2030353469852519378u }, + { 11750802462513761473u, 1268970918657824611u }, { 10076817059714813937u, 1586213648322280764u }, + { 12596021324643517422u, 1982767060402850955u }, { 5566670318688504437u, 1239229412751781847u }, + { 2346651879933242642u, 1549036765939727309u }, { 7545000868343941206u, 1936295957424659136u }, + { 4715625542714963254u, 1210184973390411960u }, { 5894531928393704067u, 1512731216738014950u }, + { 16591536947346905892u, 1890914020922518687u }, { 17287239619732898039u, 1181821263076574179u }, + { 16997363506238734644u, 1477276578845717724u }, { 2799960309088866689u, 1846595723557147156u }, + { 10973347230035317489u, 1154122327223216972u }, { 13716684037544146861u, 1442652909029021215u }, + { 12534169028502795672u, 1803316136286276519u }, { 11056025267201106687u, 2254145170357845649u }, + { 18439230838069161439u, 1408840731473653530u }, { 13825666510731675991u, 1761050914342066913u }, + { 3447025083132431277u, 2201313642927583642u }, { 6766076695385157452u, 1375821026829739776u }, + { 8457595869231446815u, 1719776283537174720u }, { 10571994836539308519u, 2149720354421468400u }, + { 6607496772837067824u, 1343575221513417750u }, { 17482743002901110588u, 1679469026891772187u }, + { 17241742735199000331u, 2099336283614715234u }, { 15387775227926763111u, 1312085177259197021u }, + { 5399660979626290177u, 1640106471573996277u }, { 11361262242960250625u, 2050133089467495346u }, + { 11712474920277544544u, 1281333180917184591u }, { 10028907631919542777u, 1601666476146480739u }, + { 7924448521472040567u, 2002083095183100924u }, { 14176152362774801162u, 1251301934489438077u }, + { 3885132398186337741u, 1564127418111797597u }, { 9468101516160310080u, 1955159272639746996u }, + { 15140935484454969608u, 1221974545399841872u }, { 479425281859160394u, 1527468181749802341u }, + { 5210967620751338397u, 1909335227187252926u }, { 17091912818251750210u, 1193334516992033078u }, + { 12141518985959911954u, 1491668146240041348u }, { 15176898732449889943u, 1864585182800051685u }, + { 11791404716994875166u, 1165365739250032303u }, { 10127569877816206054u, 1456707174062540379u }, + { 8047776328842869663u, 1820883967578175474u }, { 836348374198811271u, 2276104959472719343u }, + { 7440246761515338900u, 1422565599670449589u }, { 13911994470321561530u, 1778206999588061986u }, + { 8166621051047176104u, 2222758749485077483u }, { 2798295147690791113u, 1389224218428173427u }, + { 17332926989895652603u, 1736530273035216783u }, { 17054472718942177850u, 2170662841294020979u }, + { 8353202440125167204u, 1356664275808763112u }, { 10441503050156459005u, 1695830344760953890u }, + { 3828506775840797949u, 2119787930951192363u }, { 86973725686804766u, 1324867456844495227u }, + { 13943775212390669669u, 1656084321055619033u }, { 3594660960206173375u, 2070105401319523792u }, + { 2246663100128858359u, 1293815875824702370u }, { 12031700912015848757u, 1617269844780877962u }, + { 5816254103165035138u, 2021587305976097453u }, { 5941001823691840913u, 1263492066235060908u }, + { 7426252279614801142u, 1579365082793826135u }, { 4671129331091113523u, 1974206353492282669u }, + { 5225298841145639904u, 1233878970932676668u }, { 6531623551432049880u, 1542348713665845835u }, + { 3552843420862674446u, 1927935892082307294u }, { 16055585193321335241u, 1204959932551442058u }, + { 10846109454796893243u, 1506199915689302573u }, { 18169322836923504458u, 1882749894611628216u }, + { 11355826773077190286u, 1176718684132267635u }, { 9583097447919099954u, 1470898355165334544u }, + { 11978871809898874942u, 1838622943956668180u }, { 14973589762373593678u, 2298278679945835225u }, + { 2440964573842414192u, 1436424174966147016u }, { 3051205717303017741u, 1795530218707683770u }, + { 13037379183483547984u, 2244412773384604712u }, { 8148361989677217490u, 1402757983365377945u }, + { 14797138505523909766u, 1753447479206722431u }, { 13884737113477499304u, 2191809349008403039u }, + { 15595489723564518921u, 1369880843130251899u }, { 14882676136028260747u, 1712351053912814874u }, + { 9379973133180550126u, 2140438817391018593u }, { 17391698254306313589u, 1337774260869386620u }, + { 3292878744173340370u, 1672217826086733276u }, { 4116098430216675462u, 2090272282608416595u }, + { 266718509671728212u, 1306420176630260372u }, { 333398137089660265u, 1633025220787825465u }, + { 5028433689789463235u, 2041281525984781831u }, { 10060300083759496378u, 1275800953740488644u }, + { 12575375104699370472u, 1594751192175610805u }, { 1884160825592049379u, 1993438990219513507u }, + { 17318501580490888525u, 1245899368887195941u }, { 7813068920331446945u, 1557374211108994927u }, + { 5154650131986920777u, 1946717763886243659u }, { 915813323278131534u, 1216698602428902287u }, + { 14979824709379828129u, 1520873253036127858u }, { 9501408849870009354u, 1901091566295159823u }, + { 12855909558809837702u, 1188182228934474889u }, { 2234828893230133415u, 1485227786168093612u }, + { 2793536116537666769u, 1856534732710117015u }, { 8663489100477123587u, 1160334207943823134u }, + { 1605989338741628675u, 1450417759929778918u }, { 11230858710281811652u, 1813022199912223647u }, + { 9426887369424876662u, 2266277749890279559u }, { 12809333633531629769u, 1416423593681424724u }, + { 16011667041914537212u, 1770529492101780905u }, { 6179525747111007803u, 2213161865127226132u }, + { 13085575628799155685u, 1383226165704516332u }, { 16356969535998944606u, 1729032707130645415u }, + { 15834525901571292854u, 2161290883913306769u }, { 2979049660840976177u, 1350806802445816731u }, + { 17558870131333383934u, 1688508503057270913u }, { 8113529608884566205u, 2110635628821588642u }, + { 9682642023980241782u, 1319147268013492901u }, { 16714988548402690132u, 1648934085016866126u }, + { 11670363648648586857u, 2061167606271082658u }, { 11905663298832754689u, 1288229753919426661u }, + { 1047021068258779650u, 1610287192399283327u }, { 15143834390605638274u, 2012858990499104158u }, + { 4853210475701136017u, 1258036869061940099u }, { 1454827076199032118u, 1572546086327425124u }, + { 1818533845248790147u, 1965682607909281405u }, { 3442426662494187794u, 1228551629943300878u }, + { 13526405364972510550u, 1535689537429126097u }, { 3072948650933474476u, 1919611921786407622u }, + { 15755650962115585259u, 1199757451116504763u }, { 15082877684217093670u, 1499696813895630954u }, + { 9630225068416591280u, 1874621017369538693u }, { 8324733676974063502u, 1171638135855961683u }, + { 5794231077790191473u, 1464547669819952104u }, { 7242788847237739342u, 1830684587274940130u }, + { 18276858095901949986u, 2288355734093675162u }, { 16034722328366106645u, 1430222333808546976u }, + { 1596658836748081690u, 1787777917260683721u }, { 6607509564362490017u, 2234722396575854651u }, + { 1823850468512862308u, 1396701497859909157u }, { 6891499104068465790u, 1745876872324886446u }, + { 17837745916940358045u, 2182346090406108057u }, { 4231062170446641922u, 1363966306503817536u }, + { 5288827713058302403u, 1704957883129771920u }, { 6611034641322878003u, 2131197353912214900u }, + { 13355268687681574560u, 1331998346195134312u }, { 16694085859601968200u, 1664997932743917890u }, + { 11644235287647684442u, 2081247415929897363u }, { 4971804045566108824u, 1300779634956185852u }, + { 6214755056957636030u, 1625974543695232315u }, { 3156757802769657134u, 2032468179619040394u }, + { 6584659645158423613u, 1270292612261900246u }, { 17454196593302805324u, 1587865765327375307u }, + { 17206059723201118751u, 1984832206659219134u }, { 6142101308573311315u, 1240520129162011959u }, + { 3065940617289251240u, 1550650161452514949u }, { 8444111790038951954u, 1938312701815643686u }, + { 665883850346957067u, 1211445438634777304u }, { 832354812933696334u, 1514306798293471630u }, + { 10263815553021896226u, 1892883497866839537u }, { 17944099766707154901u, 1183052186166774710u }, + { 13206752671529167818u, 1478815232708468388u }, { 16508440839411459773u, 1848519040885585485u }, + { 12623618533845856310u, 1155324400553490928u }, { 15779523167307320387u, 1444155500691863660u }, + { 1277659885424598868u, 1805194375864829576u }, { 1597074856780748586u, 2256492969831036970u }, + { 5609857803915355770u, 1410308106144398106u }, { 16235694291748970521u, 1762885132680497632u }, + { 1847873790976661535u, 2203606415850622041u }, { 12684136165428883219u, 1377254009906638775u }, + { 11243484188358716120u, 1721567512383298469u }, { 219297180166231438u, 2151959390479123087u }, + { 7054589765244976505u, 1344974619049451929u }, { 13429923224983608535u, 1681218273811814911u }, + { 12175718012802122765u, 2101522842264768639u }, { 14527352785642408584u, 1313451776415480399u }, + { 13547504963625622826u, 1641814720519350499u }, { 12322695186104640628u, 2052268400649188124u }, + { 16925056528170176201u, 1282667750405742577u }, { 7321262604930556539u, 1603334688007178222u }, + { 18374950293017971482u, 2004168360008972777u }, { 4566814905495150320u, 1252605225005607986u }, + { 14931890668723713708u, 1565756531257009982u }, { 9441491299049866327u, 1957195664071262478u }, + { 1289246043478778550u, 1223247290044539049u }, { 6223243572775861092u, 1529059112555673811u }, + { 3167368447542438461u, 1911323890694592264u }, { 1979605279714024038u, 1194577431684120165u }, + { 7086192618069917952u, 1493221789605150206u }, { 18081112809442173248u, 1866527237006437757u }, + { 13606538515115052232u, 1166579523129023598u }, { 7784801107039039482u, 1458224403911279498u }, + { 507629346944023544u, 1822780504889099373u }, { 5246222702107417334u, 2278475631111374216u }, + { 3278889188817135834u, 1424047269444608885u }, { 8710297504448807696u, 1780059086805761106u } +}; + +#if defined(_MSC_VER) + +#include + +static inline uint32_t floor_log2(const uint64_t value) { + long index; + return _BitScanReverse64(&index, value) ? index : 64; +} + +static inline uint64_t umul128(const uint64_t a, const uint64_t b, uint64_t* const productHi) { + return _umul128(a, b, productHi); +} + +#else + +static inline uint32_t floor_log2(uint64_t value) { +# if defined(__has_builtin) && __has_builtin (__builtin_clzll) + return 63 - __builtin_clzll(value); +# else + uint32_t r = 63; + while(!(value & (1ULL) << 63)) { + value <<= 1; + r--; + } + return r; +# endif +} + +static inline uint64_t umul128(const uint64_t a, const uint64_t b, uint64_t* const productHi) { + // The casts here help MSVC to avoid calls to the __allmul library function. + const uint32_t aLo = (uint32_t)a; + const uint32_t aHi = (uint32_t)(a >> 32); + const uint32_t bLo = (uint32_t)b; + const uint32_t bHi = (uint32_t)(b >> 32); + + const uint64_t b00 = (uint64_t)aLo * bLo; + const uint64_t b01 = (uint64_t)aLo * bHi; + const uint64_t b10 = (uint64_t)aHi * bLo; + const uint64_t b11 = (uint64_t)aHi * bHi; + + const uint32_t b00Lo = (uint32_t)b00; + const uint32_t b00Hi = (uint32_t)(b00 >> 32); + + const uint64_t mid1 = b10 + b00Hi; + const uint32_t mid1Lo = (uint32_t)(mid1); + const uint32_t mid1Hi = (uint32_t)(mid1 >> 32); + + const uint64_t mid2 = b01 + mid1Lo; + const uint32_t mid2Lo = (uint32_t)(mid2); + const uint32_t mid2Hi = (uint32_t)(mid2 >> 32); + + const uint64_t pHi = b11 + mid1Hi + mid2Hi; + const uint64_t pLo = ((uint64_t)mid2Lo << 32) | b00Lo; + + *productHi = pHi; + return pLo; +} + +#endif + +// The max function is already defined on Windows. +static inline int32_t max32(int32_t a, int32_t b) { + return a < b ? b : a; +} + +static inline uint32_t pow5Factor(uint64_t value) { + const uint64_t m_inv_5 = 14757395258967641293u; // 5 * m_inv_5 = 1 (mod 2^64) + const uint64_t n_div_5 = 3689348814741910323u; // #{ n | n = 0 (mod 2^64) } = 2^64 / 5 + uint32_t count = 0; + for (;;) { + //assert(value != 0); + value *= m_inv_5; + if (value > n_div_5) + break; + ++count; + } + return count; +} + +// Returns true if value is divisible by 5^p. +static inline bool multipleOfPowerOf5(const uint64_t value, const uint32_t p) { + // I tried a case distinction on p, but there was no performance difference. + return pow5Factor(value) >= p; +} + +// Returns true if value is divisible by 2^p. +static inline bool multipleOfPowerOf2(const uint64_t value, const uint32_t p) { + //assert(value != 0); + //assert(p < 64); + // __builtin_ctzll doesn't appear to be faster here. + return (value & ((1ull << p) - 1)) == 0; +} + +static inline double int64Bits2Double(uint64_t bits) { + double f; + memcpy(&f, &bits, sizeof(double)); + return f; +} + +// Returns e == 0 ? 1 : [log_2(5^e)]; requires 0 <= e <= 3528. +static inline int32_t log2pow5(const int32_t e) { + // This approximation works up to the point that the multiplication overflows at e = 3529. + // If the multiplication were done in 64 bits, it would fail at 5^4004 which is just greater + // than 2^9297. + //assert(e >= 0); + //assert(e <= 3528); + return (int32_t) ((((uint32_t) e) * 1217359) >> 19); +} + +// Returns e == 0 ? 1 : ceil(log_2(5^e)); requires 0 <= e <= 3528. +static inline int32_t ceil_log2pow5(const int32_t e) { + return log2pow5(e) + 1; +} + +static inline uint64_t shiftright128(const uint64_t lo, const uint64_t hi, const uint32_t dist) { + // We don't need to handle the case dist >= 64 here (see above). + //assert(dist < 64); + //assert(dist > 0); + return (hi << (64 - dist)) | (lo >> dist); +} + +// m is maximum 55 bits +static inline uint64_t mulShift64(const uint64_t m, const uint64_t* const mul, const int32_t j) { + uint64_t high1; // 128 + const uint64_t low1 = umul128(m, mul[1], &high1); // 64 + uint64_t high0; // 64 + umul128(m, mul[0], &high0); // 0 + const uint64_t sum = high0 + low1; + if(sum < high0) + ++high1; // overflow into high1 + return shiftright128(sum, high1, j - 64); +} + +size_t parseDouble(const char *buffer, size_t len, double *result) { + if(len == 0) + return 0; + + int m10digits = 0; + int e10digits = 0; + uint64_t m10 = 0; + int32_t e10 = 0; + bool signedM = false; + bool signedE = false; + + size_t dotIndex = len; + size_t eIndex = len; + size_t i = 0; + + if(buffer[i] == '-') { + signedM = true; + i++; + } + + for(; i < len; i++) { + char c = buffer[i]; + if(c == '.') { + if(dotIndex != len) + return 0; + dotIndex = i; + continue; + } + if((c < '0') || (c > '9')) + break; + if(m10digits >= 17) + return 0; + m10 = 10 * m10 + (c - '0'); + if(m10 != 0) + m10digits++; + } + if(i < len && ((buffer[i] == 'e') || (buffer[i] == 'E'))) { + eIndex = i; + i++; + if(i < len && ((buffer[i] == '-') || (buffer[i] == '+'))) { + signedE = buffer[i] == '-'; + i++; + } + for(; i < len; i++) { + char c = buffer[i]; + if((c < '0') || (c > '9')) + return 0; + + // TODO: Be more lenient. Return +/-Infinity or +/-0 instead. + if(e10digits > 3) + return 0; + + e10 = 10 * e10 + (c - '0'); + if(e10 != 0) + e10digits++; + } + } + + // The input was not entirely parsed + if(i < len) + return 0; + + if(signedE) + e10 = -e10; + + e10 -= dotIndex < eIndex ? eIndex - dotIndex - 1 : 0; + if(m10 == 0) { + *result = signedM ? -0.0 : 0.0; + return len; + } + + if((m10digits + e10 <= -324) || (m10 == 0)) { + // Number is less than 1e-324, which should be rounded down to 0; return +/-0.0. + uint64_t ieee = ((uint64_t) signedM) << (DOUBLE_EXPONENT_BITS + DOUBLE_MANTISSA_BITS); + *result = int64Bits2Double(ieee); + return len; + } + + if(m10digits + e10 >= 310) { + // Number is larger than 1e+309, which should be rounded to +/-Infinity. + uint64_t ieee = (((uint64_t) signedM) << (DOUBLE_EXPONENT_BITS + DOUBLE_MANTISSA_BITS)) | (0x7ffull << DOUBLE_MANTISSA_BITS); + *result = int64Bits2Double(ieee); + return len; + } + + // Convert to binary float m2 * 2^e2, while retaining information about whether the conversion + // was exact (trailingZeros). + int32_t e2; + uint64_t m2; + bool trailingZeros; + if(e10 >= 0) { + // The length of m * 10^e in bits is: + // log2(m10 * 10^e10) = log2(m10) + e10 log2(10) = log2(m10) + e10 + e10 * log2(5) + // + // We want to compute the DOUBLE_MANTISSA_BITS + 1 top-most bits (+1 for the implicit leading + // one in IEEE format). We therefore choose a binary output exponent of + // log2(m10 * 10^e10) - (DOUBLE_MANTISSA_BITS + 1). + // + // We use floor(log2(5^e10)) so that we get at least this many bits; better to + // have an additional bit than to not have enough bits. + e2 = floor_log2(m10) + e10 + log2pow5(e10) - (DOUBLE_MANTISSA_BITS + 1); + + // We now compute [m10 * 10^e10 / 2^e2] = [m10 * 5^e10 / 2^(e2-e10)]. + // To that end, we use the DOUBLE_POW5_SPLIT table. + int j = e2 - e10 - ceil_log2pow5(e10) + DOUBLE_POW5_BITCOUNT; + //assert(j >= 0); + m2 = mulShift64(m10, DOUBLE_POW5_SPLIT[e10], j); + // We also compute if the result is exact, i.e., + // [m10 * 10^e10 / 2^e2] == m10 * 10^e10 / 2^e2. + // This can only be the case if 2^e2 divides m10 * 10^e10, which in turn requires that the + // largest power of 2 that divides m10 + e10 is greater than e2. If e2 is less than e10, then + // the result must be exact. Otherwise we use the existing multipleOfPowerOf2 function. + trailingZeros = e2 < e10 || (e2 - e10 < 64 && multipleOfPowerOf2(m10, e2 - e10)); + } else { + e2 = floor_log2(m10) + e10 - ceil_log2pow5(-e10) - (DOUBLE_MANTISSA_BITS + 1); + int j = e2 - e10 + ceil_log2pow5(-e10) - 1 + DOUBLE_POW5_INV_BITCOUNT; + //assert(-e10 < DOUBLE_POW5_INV_TABLE_SIZE); + m2 = mulShift64(m10, DOUBLE_POW5_INV_SPLIT[-e10], j); + trailingZeros = multipleOfPowerOf5(m10, -e10); + } + + // Compute the final IEEE exponent. + uint32_t ieee_e2 = (uint32_t) max32(0, e2 + DOUBLE_EXPONENT_BIAS + floor_log2(m2)); + + if(ieee_e2 > 0x7fe) { + // Final IEEE exponent is larger than the maximum representable; return +/-Infinity. + uint64_t ieee = (((uint64_t) signedM) << (DOUBLE_EXPONENT_BITS + DOUBLE_MANTISSA_BITS)) | (0x7ffull << DOUBLE_MANTISSA_BITS); + *result = int64Bits2Double(ieee); + return len; + } + + // We need to figure out how much we need to shift m2. The tricky part is that we need to take + // the final IEEE exponent into account, so we need to reverse the bias and also special-case + // the value 0. + int32_t shift = (ieee_e2 == 0 ? 1 : ieee_e2) - e2 - DOUBLE_EXPONENT_BIAS - DOUBLE_MANTISSA_BITS; + //assert(shift >= 0); + + // We need to round up if the exact value is more than 0.5 above the value we computed. That's + // equivalent to checking if the last removed bit was 1 and either the value was not just + // trailing zeros or the result would otherwise be odd. + // + // We need to update trailingZeros given that we have the exact output exponent ieee_e2 now. + trailingZeros &= (m2 & ((1ull << (shift - 1)) - 1)) == 0; + uint64_t lastRemovedBit = (m2 >> (shift - 1)) & 1; + bool roundUp = (lastRemovedBit != 0) && (!trailingZeros || (((m2 >> shift) & 1) != 0)); + + uint64_t ieee_m2 = (m2 >> shift) + roundUp; + //assert(ieee_m2 <= (1ull << (DOUBLE_MANTISSA_BITS + 1))); + ieee_m2 &= (1ull << DOUBLE_MANTISSA_BITS) - 1; + if(ieee_m2 == 0 && roundUp) { + // Due to how the IEEE represents +/-Infinity, we don't need to check for overflow here. + ieee_e2++; + } + + uint64_t ieee = (((((uint64_t) signedM) << DOUBLE_EXPONENT_BITS) | (uint64_t)ieee_e2) << DOUBLE_MANTISSA_BITS) | ieee_m2; + *result = int64Bits2Double(ieee); + return len; +}