Source to Binary - journey of V8 javascript engine

by Taketoshi Aono(青野健利 a.k.a brn)

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Name @brn (ꫬꅿ⨳ⵃ) Occupation ؿٗٝزؒٝسؒٝآص،٥ط؎ذ؍ـؒٝآص، Company Cyberagent ،سذؙأةآؔ AI Messenger Blog http://abcdef.gets.b6n.ch/ Twitter https://twitter.com/brn227 GitHub https://github.com/brn

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Agenda •  What is V8? •  Execution ﬂow of V8 •  Parsing •  Abstract Syntax Tree •  Ignition – BytecodeInterpreter •  CodeStubAssembler •  Builtins / Runtime •  Optimization / Hidden Class / Inline Caching •  TurboFan / Deoptimization

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What is V8? V8הכGoogle爡ָ㹋鄲׃׋javascriptؒٝآٝדծ Google Chrome/Node.JSךjavascriptؒٝآٝח䱰欽ׁ׸גְתׅկ

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Execution Flow

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Source AST Bytecode Graph Assembly ﬁrst time hot code

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Parsing

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Basic parsing V8כا٦أ؝٦س׾ػ٦أ׃גASTח㢌䳔ׅ׷ ASTהכAbstractSyntaxTreeך殛獥䬄韋圓俑加הㄎל׸׷ Parsing

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if (x) { x = 100 }

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IF CONDITION THEN BLOCK EXPRESSION STATEMENT ASSIGN VAR PROXY (X) LITERAL (100) if (x) { x = 100

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Problems

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Parsing all functions - Slow ׅץגך؝٦س׾剑ⴱחػ٦أׅ׷ךכ֮ת׶״׹׃ֻזְ ׮׃ػ٦أ׃׋؝٦سָ㹋遤ׁ׸זֽ׸ל䠐㄂ָזְ Parsing

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Split parsing phase ػ٦أ׾鹼䒀׃ג遤ֲ׋׭חծػ٦أ׾✳媮ꥡחⴓֽ׷ Parsing

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PreParsing ✲⵸חׅץגךꟼ侧ךٖ؎،ؐز׾ ػ٦أ׃גֶֻ Parsing

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function x(a, b) { return a + b; } FUNCTION(X) parameter-count: 2 start-position: 1 end-position: 34 use-super-property: false …

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// when x is called x() FUNCTION NAME (x) RETURN LITERAL(1)

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Lazy Parsing V8כ㹋ꥷח״ן׌ׁ׸׷תדػ٦أ׾鹼䒀ׅ׷ ꟼ侧כㄎן⳿ׁ׸גⴱ׭ג؝ٝػ؎ׁٕ׸׷ Parsing

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More About https://docs.google.com/presentation/d/1b- ALt6W01nIxutFVFmXMOyd_6ou_6qqP6S0Prmb1iDs/present? slide=id.p Parsing

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Abstract Syntax Tree

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AST Rewriting Parserח״׏ג欰䧭ׁ׸׋AST׾㢌䕎ׅ׷ ְֻאַ稱➜ AbstractSyntaxTree

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Subsclass constructor return 竰䪫׃׋ؙٓأך؝ٝأزؙٓة׾㢌䕎ׅ׷ 崢欰ؙٓأך؝ٝأزؙٓةד䒭׾return׃גְ׷儗כծ 3갪怴皾㶨ח㢌䳔׃גծ 䒭ך穠卓ָundeﬁned׌׏׋㜥さחכthis׾䨱ׅկ AbstractSyntaxTree

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constructor() {! super();! return expr! }! ! constructor() {! super();! var tmp;! return (temp = expr) === undefined?! this: temp;! }!

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for (let/const/var in/of e) for-in/ofךⴱ劍⻉דconst/let׾⢪ֲ׋׭חծⰋ⡤׾ـٗحؙד㔲 ׫㢌侧׾㹑鎉ׅ׷կ AbstractSyntaxTree

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for (const key of e) {! ...! }!

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{! var temp;! for (temp of e) {! const x = temp;! ...! }! let x! }!

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Spread operator doהfor-ofח縧ֹ䳔ִגⳢ椚 AbstractSyntaxTree

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const x = [1,2,3];! const y = [...x];!

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do {! $R = [];! for ($i of x)! %AppendElement($R, $i);! $R! }!

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Ecmascript? – Binary AST ➙תד鋅׋״ֲחASTך؟؎ؤכ穠圓㣐ְֹךדծ ׉׸׾㖇簭ׅ׷䲿周 Parsing

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Ignition

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Bytecode Interpreter V8כ欰䧭׃׋AST׾1~4byteךBytecodeח㢌䳔׃גַ׵㹋遤ׅ ׷ Ignition

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How does it work? ♧אך،ُؗيٖ٦ة٦׾⪒ִٖآأةك٦أד⹛⡲ׅ׷؎ٝ ة٦فٔة Ignition

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Pseudo javascript code Javascriptד圓鸡׾垷⦺ׅ׷הֿך״ֲחז׷ Ignition

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How to create bytecode? BytecodeכASTַ׵AstVisitor׾ⵃ欽׃ג欰䧭ׁ׸׷ AstVisitorכVistorػة٦ٝ׾ⵃ欽׃׋ؙٓأדծ AST׾帾ׁ⮚⯓䱱稊׃זָ׵㼎䘔ׅ׷؝٦ٕغحؙꟼ侧׾ㄎן⳿ ׅ Ignition

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BytecodeArray 欰䧭ׁ׸׋BytecodeכBytecodeArrayח呓秛ׁ׸׷ BytecodeArrayכꟼ侧⽃⡘ד㶷㖈ׅ׷ Ignition

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Dispatch Table Stub(Machine Code) BytecodeArray Dispatch Tableから対応するHandlerを取り出して実行 0 1 3 4 5 6 7 8 5 6 1

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InterpreterEntryTrampoline 剑穄涸ח欰䧭ׁ׸׋BytecodeכInterpreterEntrynTrampolineה ㄎל׸׷Builtin؝٦سַ׵㹋遤ׁ׸׷ InterpreterEntryTrampolineכAssemblyח؝ٝػ؎ׁٕ׸ծ 鸐䌢ךCךꟼ侧הㄎן⳿ׁ׸׷ Ignition

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InterpreterEntryTrampoline(Assembly) Script::Run Call as C function Ignition DispatchTable Dispatch First bytecode

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Ignition Handler ⯓玎亻⡂؝٦سד爙׃׋BytecodeHandlersכV8דכ Ignition Handlerהㄎל׸גְ׷ Ignition HandlerכCodeStubAssemblerהְֲDSLד鎸鶢ׁ׸ג ְ׷ Iginition

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CodeStub Assember

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What is CodeStubAssmber? CodeStubAssembler(CSA)כ؝٦س欰䧭׾ؚٓؿ欰䧭ח䬄韋⻉׃ ׋V8ⰻ鿇ךDSL 㹋遤✮㹀Node׾穈׫甧ג׷׌ֽדծCodeGeneratorח״׏גぐ ،٦ؗذؙثٍぢֽך؝٦سָ欰䧭ׁ׸׷׋׭ծ،إٝـٔ鎉铂 ׾ְ׍ְ׍倜׋ח剅ֻ䗳銲ָזְ CodeStubAssembler

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IGNITION_HANDLER(JumpIfToBooleanFalse, InterpreterAssembler) {! Node* value = GetAccumulator();! // Accumulatorの値を取得! Node* relative_jump = BytecodeOperandUImmWord(0);! // 引数のoperandを取得! Label if_true(this), if_false(this);! BranchIfToBooleanIsTrue(value, &if_true, &if_false);! // valueがtrueならif_true、falseならif_false! Bind(&if_true);! Dispatch();! Bind(&if_false);! // operandのbytecodeまでjump! Jump(relative_jump);! }!

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Graph based DSL ֿךCodeStubAssemblerךֶַ־ד㹋ꥷך،٦ؗذؙثٍぢֽ ך،إٝـٓ׾擾濼׃גְזֻג׮֮׵׋ח؝٦س׾鷄⸇ׅ׷ֿ הָ㺁僒חז׶ծ ת׋〳铣䚍׮ꬊ䌢ח넝ֻז׏גְ׷ CodeStubAssembler

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Dispatch Table 00 01 02 04 08 0f 10 10 Node Node Node Operator Operator IGNITION_HANDLER Stub (Mahine Code Fragment) グラフからコードを生成生成したコードを、 DispatchTableの対応するバイトコードのインデックスへ登録 Assemble

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Assembler 㹋ꥷחぐ،٦ؗذؙثٍぢֽך؝٦س׾⳿⸂ׅ׷ X64ぢֽךjmpص٦ٌصحؙ׾׍׳׏ה׌ֽ鋖ְג׫״ֲ CodeStubAssembler

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void Assembler::jmp(! Handle

 target,!
RelocInfo::Mode rmode!
) {!
EnsureSpace ensure_space(this);!
// 1110 1001 #32-bit disp.!
// ここでメモリ上にアセンブラを書き出す!
emit(0xE9);!
emit_code_target(target, rmode);!
}!

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Where to use BuiltinsכAssemblerؙٓأ׾ⵃ欽׃גぐ،٦ؗذؙثٍ嫣ך Stubָ鎸鶢ׁ׸גְ׷ ♧鿇CSA׾⢪ֲ皘䨽׮֮׷(*-gen.cc) Ignition HandlerכקרⰋגָCSAד鎸鶢ׁ׸גְ׷ CodeStubAssembler

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Builtins & Runtime

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Builtins BuiltinsכV8ך饯⹛儗ח؝ٝػ؎ׁٕ׸׷،إٝـٓך؝٦س晙 ꟼ侧ך״ֲחCallBuiltin穗歋דㄎן⳿ׁ׸׷ Stubה׮ㄎל׸׷ 㹋遤儗ך剑黝⻉כ遤׻׸זְ Builtins & Runtime

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Runtime RuntimeכBuiltinsװ׉ך➭ך،إٝـٓ؝٦سַ׵ㄎן⳿ֿׅ הָדֹ׷C++ך؝٦س Javascriptך⚅歲ַ׵C++ך⚅歲׾אזּ؝٦س晙ずֻׄ㹋遤儗ך剑黝⻉כ遤׻׸זְ Builtins & Runtime

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Hidden Class

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What is Hidden Class? Javascriptחכ㘗ָזְךדؔـآؙؑز׾鋉㹀ׅ׷׮ךָ搀ְկ ׉ך׋׭ծV8כؔـآؙؑزך圓鸡荈⡤׾㘗ך״ֲח䪔׏גְ׷կ ֿ׸׾Hidden Classהㄎע Hidden Class

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•  Hidden Class const point1 = {x: 0, y: 0};! const point2 = {x: 0, y: 0};! Map FixedArray [ {x: {offset: 0}}, {y: {offset: 1}} ]

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Map ׋הִJavascript♳דכⴽךؔـآؙؑزד֮׏ג׮ծ ずׄ圓鸡׾䭯׏גְ׸לずׄHidden Class׾Ⱏ剣ׅ׷ ׉׃גֿךؔـآؙؑزך酅ח֮׷圓鸡׾Mapהㄎע Hidden Class

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class PointA {! constructor() {! this.x = 0;! this.y = 0;! }! }! const pointAInstance = new PointA();! ! class PointB {! constructor() {! this.y = 0;! this.x = 0;! }! }! const pointBInstance = new PointB();! // PointAInstance.Map !== PointBInstance.Map!

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Layout Mapؔـآؙؑزכַז׶⿑㺘חفٗػذ؍ךoffset׾ثؑحؙ ׅ׷׋׭ծٔذٕٓךⴱ劍⻉갫٥فٗػذ؍ךⴱ劍⻉갫٥فٗػ ذ؍ך侧ָ麩ֲהⴽךMapָⶴ׶䔲ג׵׸׷ Hidden Class

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Map Transition ׃ַ׃فٗػذ؍ך㟓幾ָ걼籕ח饯ֿ׷Javascriptדծ嫣㔐Map ׾欰䧭ׅ׷ה؝أزָ搀鋔דֹזְךדכ V8כفٗػذ؍ך㟓幾ָ֮׏׋㜥さחכMap׾Ⱏ剣׃זָ׵ծ 㟓ִ׋鿇ⴓך׫ך倜׃ְMap׾欰䧭ׅ׷ ֿ׸׾Map Transitionהㄎע Hidden Class

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What's Happening? Hidden Classָ֮׷ה⡦ָ㴍׃ְַהְֲהծ ؔـآؙؑزךفٗػذ؍،ؙإأװ㘗ךثؑحؙ׾״׶넝鸞חծ ״׶㸜Ⰻח遤ִ׷״ֲחז׷ Hidden Class

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Inline Caching

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What is Inline Caching فٗػذ؍،ؙإأך넝鸞⻉ך׋׭ח麓⿠ך،ؙإأ׾ٍؗح ءُ׃גֶֻ Inline Caching

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function x(obj) {! return obj.x + obj.y;! }! ! x({x: 0, y: 0});! x({x: 1, y: 1});! x({x: 2, y: 2});!

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Search Property ؔـآؙؑزַ׵فٗػذ؍׾䱱ׅ׋׭חכծ HashMapװFixedArrayַ׵فٗػذ؍׾ٗ٦سׅ׷ ׃ַ׃׉׸׾嫣㔐遤ֲךכꬊ䌢ח鹼ְ Inline Caching

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Reduce Property Access ֿך⢽דכxהyפך،ؙإأָずׄMap׾䭯אؔـآؙؑزח㼎 ׃ג⡦䏝׮㹋遤ׁ׸גְ׷ ׅדחobjכ{x, y}ךMapה׻ַ׏גְ׷ךד֮׸לծ 䔲搫ًٌٖٔ؎،ؐز׮׻ַ׏גְ׷ךדծ湫䱸offset׾䭷㹀׃ ג،ؙإأ׃׋קֲָ傍ְ Inline Caching

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Cache זךדծ暴㹀ךMapך،ؙإأ׾鎸䥉׃גֶֻ ֮׷فٗػذ؍פ،ؙإأ׃׋㜥さծ׉ךMapؔـآؙؑز׾鎸䥉ׅ׷ֿהד2㔐湡⟃꣬ךفٗػذ؍،ؙإأָ넝鸞⻉ׁ׸׷ Inline Caching

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x({x: 0, y: 0});! // uninitialized! x({x: 1, y: 1});! // stub_call! x({x: 2, y: 2});! // found ic! x({x: 1, y: 1, z: 1})! // load ic miss! x({x: 1, y: 1, foo() {}});! // load ic miss!

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Cache Miss ׋׌׃ծMapָ㢌⻉׃׋㜥さחכ䔲搫CacheךMissؼحزָ饯ֹ ׷ךדծת׋فٗػذ؍׾ٗ٦س׃ג倜׋ח鎸䥉׃湫ׅ ׋׌׃ׅץג׾鎸ꐮׅ׷ךכ♶〳腉זךדծ4אתדMapؔـ آؙؑز׾鎸ꐮׅ׷ Inline Cache

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Cahce State ٍؗحءُך朐䡾כ⟃♴ך״ֲח鼂獳ׅ׷ PreMonomorphic Monomorphic Polymorphic Megamorphic Inline Caching

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Pre Monomorphic ؝٦س♳ך鿪さד劢ⴱ劍ַוֲַⴻ㹀ׅ׷׋׭ח㶷㖈ׅ׷ךדծ ֮ת׶䠐㄂כזְ Inline Caching

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Monomorphic ⽃♧ךMapפך،ؙإأ׃ַ㶷㖈׃זְ朐䡾椚䟝涸ז朐䡾ה鎉ִ׷ Inline Caching

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Polymorphic MapָFixedArrayח呓秛ׁ׸גֶ׶醱侧ךMapַ׵嗚稊׃ג فٗػذ؍،ؙإأ׾㹋遤ׅ׷ ٍؗحءُ荈⡤כׁ׸גְ׷ךדת׌넝鸞 Inline Caching

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Megamorphic ֮ת׶חMissָ㢳ְךדծMapך鎸ꐮ׾⨡姺׃׋朐䡾 איחStubַ׵GetProperty׾ㄎן⳿׃גفٗػذ؍׾《䖤ׅ׷ 剑׮鹼ְ朐䡾 Inline Caching

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Optimization

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Hot or Small 䌢ח؝٦س׾剑黝⻉ׅ׷ךכꬊ䌢ח搀꼽 ⟃♴ך勴⟝ח䔲גכת׷؝٦س׾剑黝⻉ׅ׷ •  (ꟼ侧ךغ؎ز؝٦سꞿ/ 1200) + 2ך㔐侧ꟼ侧ָㄎן⳿ׁ׸ גְ׷ •  ꟼ侧ָ㼭ְׁ(غ؎ز؝٦سךꞿָׁ90劢弫) Optimization

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Optimization Budget غ؎ز؝٦س㹋遤⚥חぐꟼ侧חכ剑黝⻉✮皾ָⶴ׶䮶׵׸גֶ׶ծ ׉ך⦼ָ0׾ⴖ׷ה؝٦س剑黝⻉⦪酡הז׷ Optimization

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For loop ٕ٦فדכJumpLoopהְֲغ؎ز؝٦سָ⳿⸂ׁ׸׷ ֿךJumpLoopך⚥ד䨱׶⯓ך،سٖأ⦼ךoffset׾ꅾ׫ח׃גծ ⯓玎ך✮皾ַ׵⦼׾䒷ֹծ׉׸ָ0׾ⶴ׏׋׵ٕ٦فⰻך剑黝⻉ ָ涪欰ׅ׷ Optimization

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function id(v) {return v;}! function x(v) {! for (var i = 0; i < 10000; i++) {! id(v + i);! }! }! x(1);!

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0x1bb9e5e2935e LdaSmi.Wide [1000] 0x1bb9e5e2937e JumpLoop [32], [0] (0x1bb9e5e2935e @ 4) Bytecode length = 100 if (budget –= 100 < 0) { OptimizeAndOSR(); }

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OSR - OnStackReplacement ؝ٝػ؎ׁٕ׸גغ؎ز؝٦سַ׵堣唒铂ח㢌䳔ׁ׸׋؝٦سכծ ٕ٦فך鷿⚥ד굲ן⯓ָ剅ֹ䳔ִ׵׸ג倜׋ז堣唒铂ך؝٦سָ 㹋遤ׁ׸׷ Optimization

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For function ꟼ侧ך㜥さכReturnغ؎ز؝٦سָ䗳׆欰䧭ׁ׸׷ ׉ֿדInterruptָ遤׻׸ג✮皾ךثؑحָؙ涪欰ׅ׷ Optimization

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function x() {! const x = 1 + 1;! }! x();!

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0x3d22953a917a StackCheck 0x3d22953a9180 Return Bytecode length 30 if (budget -= 30 < 0) { OptimizeConcurrent(); }

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Concurrent Compilation ꟼ侧׾剑黝⻉ׅ׷㜥さכծ⚛⴨؝ٝػ؎ָٕꬊず劍ח遤׻׸׷ ׉ך׋׭如㔐⟃꣬ךꟼ侧ㄎן⳿׃ָ䗳׆剑黝⻉ׁ׸גְ׷׻ֽד כזְ Optimization

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CompilationQueue CompilationJob CompilationJob CompilationJob Hot Function Bytecode Called Hot Function(Queued) Bytecode Called Hot Function(Queued) Bytecode Called Optimized Function Assembly Called

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const x = x => x;! const y = () => {! for (let i = 0; i < 1000; i++) {! x(i);! }! ! for (let i = 0; i < 1000; i++) {! x(i);! }! };! y();!

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0x13b567fa924e LdaSmi.Wide [1000] 0x13b567fa9268 JumpLoop [26], [0] (0x13b567fa924e @ 4) Bytecode length 26 budget –= 26 0x13b567fa926e LdaSmi.Wide [1000] 0x13b567fa9288 JumpLoop [26], [0] (0x13b567fa926e @ 36) Bytecode length 26 budget –= 26 0x13b567fa928c Return budget –= all_bytecode_length

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Budget for function ׋הִٕ٦فָⴓⶴׁ׸גְג׮Ⰻ⡤ך✮皾׾Returnד׮鎘皾ׅ ׷ךד㉏겗זֻ剑黝⻉ָ遤׻׸׷ Optimization

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TurboFan

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What is TurboFan? TurboFanהכV8ך剑黝⻉أةحؙךֿה V8כBytecodeַ׵剑黝⻉؝ٝػ؎ٕ׾遤ֲ㜥さחծ ♧傉IR׾欰䧭ׅ׷ ֿךGraph欰䧭ה剑黝⻉׾遤ֲךָTurboFan TurboFan

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Bytecode IR TurboFan Optimization & CodeGeneration

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IR 䬄韋涸ז㹋遤ـٗحؙ Control Flow Graph TurboFan

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#22:Branch[None](#21:SpeculativeNumberLessThan, #9:Loop) #28:IfTrue(#22:Branch) #30:JSStackCheck(#11:Phi, #32:FrameState, #21:SpeculativeNumberLessThan, #28:IfTrue) #33:JSLoadGlobal[0x2f3e1c607881 , 1] (#11:Phi, #34:FrameState, #30:JSStackCheck, #30:JSStackCheck) #2:HeapConstant[0x2f3e1c6022e1 ]() #39:FrameState #36:StateValues[sparse:^^](#12:Phi, #33:JSLoadGlobal) #37:FrameState#35:Checkpoint(#37:FrameState, #33:JSLoadGlobal, #33:JSLoadGlobal) #38:JSCall[2, 15256, NULL_OR_UNDEFINED] (#33:JSLoadGlobal, #2:HeapConstant, #11:Phi, #39:FrameState, #35:Checkpoint, #33:JSLoadGlobal) #9:Loop(#0:Start, #38:JSCall)

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Optimization TurboFanכGraphח㼎׃ג剑黝⻉׾遤ֲ TurboFan

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inline ꟼ侧ㄎן⳿׃ךInline⻉ trimming ⵋ麦׃זְNodeך⵴ꤐ type 㘗䱿锷 typed-lowering 㘗ח㛇בְג䒭װㄏ⟀׾״׶知⽃זⳢ椚ח縧ֹ䳔ִ׷ loop-peeling ٕ٦فⰻךⳢ椚׾㢩ח⳿ׅկ

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loop-exit-elimination LoopExit׾⵴ꤐ load-elimination 搀꼽ז⦼ך铣׫⳿׃װcheck׾⵴ꤐ simpliﬁed-lowering ״׶Ⱗ⡤涸ז⦼דㄏ⟀׾ءٝفٕח㢌䳔ׅ׷ generic-lowering JSفٖؿ؍حؙأך➰ֻㄏ⟀׾״׶ءٝفٕזㄎן⳿׃װ stubךㄎן⳿׃ח㢌䳔ׅ׷ dead-code-elimination ⵋ麦♶腉؝٦سך⵴ꤐ

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Code generation 剑穄涸חInstructionSelectorהְֲؙٓأָregisterךⶴ➰׾遤 ְծ ֿךؚٓؿַ׵CodeGeneratorָ堣唒铂׾欰䧭׃ג PC(ProgramCounter)ח،إٝـٔ׾剅ֹ⳿׃גְֻ Optimization

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Deoptimization

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What is Deoptimization? Deoptimization(膴剑黝⻉)הכ剑黝⻉׃׋Assembly؝٦سח✮劍 ׇט⦼ָ床׏׋㜥さחծⱄ䏝؝ٝػ؎ٕ׃湫ׅ堣腉 ׮׍׹׿㼰זְח馉׃׋ֿהכזְ Deoptimizationָ涪欰ׅ׷⢽׾然钠׃ג׫״ֲ Deoptimization

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const id = x => x;! const test = obj => {! for (let i = 0; i < 100000; i++) {! id(obj.x);! }! };! ! test({x: 1});! test({x: 1, y: 1});!

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Wrong Map ➙ך⢽דכ剑ⴱח{x}ךMapח㼎׃ג剑黝⻉ׁ׸׋Assembly׾⳿ ⸂׃׋ָծ ✳㔐湡ךㄎן⳿׃ָ{x,y}ךMap׌׏׋׋׭חծⱄ؝ٝػ؎ٕ׾⡭ ⭑זֻׁ׸ג׃ת׏׋ ׍׳׏ה׌ֽAssembly׾鋖ְג׫״ֲ Deoptimization

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0x451eb30464c 8c 48b9f1c7d830391e0000 REX.W movq rcx, 0x1e3930d8c7f1 0x451eb304656 96 483bca REX.W cmpq rcx,rdx 0x451eb304659 99 0f8591000000 jnz 0x451eb3046f0 ;; Check Map!! ... 0x451eb3046f0 130 e81ff9cfff call 0x451eb004014 ;; deoptimization bailout 2

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Bailout ֿך״ֲח⳿⸂ׁ׸׋؝٦سחMap׾然钠ׅ׷؝٦س׮ろת׸ג ְ׷ Deoptimizationָ遤׻׸׷ה؝٦سכBytecode㹋遤ח䨱׷ָծ ֿ׸׾Bailoutהㄎע Deoptimization

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Summary ⟃♳ָV8ָJS׾㹋遤ׅ׷䊨玎ד֮׷ 儗꟦ך鿪さ♳GCכ満ְ׋ V8ך؝٦سٔ٦ر؍ؚٝך䪮遭瘝כת׋ـؚٗח剅ֻ✮㹀 http://abcdef.gets.b6n.ch/ ׀幠耮֮׶ָהֲ׀ְׂת׃׋