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diff --git a/files/zh-cn/mozilla/projects/spidermonkey/internals/bytecodes/index.html b/files/zh-cn/mozilla/projects/spidermonkey/internals/bytecodes/index.html deleted file mode 100644 index 7c47ffb7ae..0000000000 --- a/files/zh-cn/mozilla/projects/spidermonkey/internals/bytecodes/index.html +++ /dev/null @@ -1,30 +0,0 @@ ---- -title: 字节码 -slug: Mozilla/Projects/SpiderMonkey/Internals/Bytecodes -tags: - - SpiderMonkey -translation_of: Mozilla/Projects/SpiderMonkey/Internals/Bytecodes ---- -<div>{{SpiderMonkeySidebar("Internals")}}</div> - -<h2 id="背景知识">背景知识</h2> - -<p>SpiderMonkey字节码是JavaScript引擎使用的标准代码表示形式。JavaScript前端根据源文本构建AST，然后根据JSScript数据结构的一部分从AST生成基于堆栈的字节码。字节码可以引用原子和对象（通常通过数组索引），这些原子和对象也包含在JSScript数据结构中。</p> - -<p>在引擎内，所有字节码都在堆栈帧内执行。堆栈帧与全局（顶级）代码和<code>eval</code>代码相关联。堆栈上的框架为几个不同类别的JavaScript值（标记值格式）留出空间。单个JavaScript值空间称为“插槽”，类别为：</p> - -<ul> - <li>参数槽：保存传递给当前框架的实际参数。</li> - <li>本地插槽：保存当前代码中使用的本地变量。</li> - <li>表达式槽：保存在堆栈上计算表达式所需的临时空间。例如，<code>(a + b) + c</code>会压入a，然后压入b，再压入+，然后压入c，再压入+，依此类推。这需要最多两个表达槽的深度。</li> -</ul> - -<p>还有一些保留给专用功能的插槽，用于处理<code>this</code>和<code>callee</code>返回值。.</p> - -<p>总有一个“堆栈顶部”（TOS），它对应于推入表达式堆栈的最新值。所有字节码都根据该位置隐式运行。</p> - -<h2 id="字节码列表">字节码列表</h2> - -<p>所有操作码都用<code> [-popcount, +pushcount] </code>标注，以表示整个执行的堆栈效果。</p> - -<p>字节码列表已移至 <a href="/en-US/docs/Mozilla/Projects/SpiderMonkey/Internals/Bytecode" title="SpiderMonkey Internals: Bytecode Descriptions">SpiderMonkey Internals: Bytecode Descriptions</a> 页面。</p> diff --git a/files/zh-cn/mozilla/projects/spidermonkey/internals/functions/index.html b/files/zh-cn/mozilla/projects/spidermonkey/internals/functions/index.html deleted file mode 100644 index 91d96b22eb..0000000000 --- a/files/zh-cn/mozilla/projects/spidermonkey/internals/functions/index.html +++ /dev/null @@ -1,73 +0,0 @@ ---- -title: Functions -slug: Mozilla/Projects/SpiderMonkey/Internals/Functions -translation_of: Mozilla/Projects/SpiderMonkey/Internals/Functions ---- -<div>{{SpiderMonkeySidebar("Internals")}}</div> - -<p>There are several flavors of JavaScript function. All are <code>JSObject</code>s of the same class, <code>js_FunctionClass</code>.</p> - -<p>这里有些Javscript函数，它们属于JSObjects</p> - -<p>(But note that objects of other classes can be callable and can even have <code>typeof obj == "function"</code>.)</p> - -<p>（也存在其他可被Call的对象）</p> - -<h2 id="Script_functions">Script functions</h2> - -<p>Functions written in JavaScript and compiled to bytecode. There are four variations that affect how NameExpressions are evaluated. (NameExpressions are basic expressions like <code>String</code> and <code>x</code> that would eat up a huge amount of run time if the engine weren't smart enough to avoid symbol table lookups.)</p> - -<p><strong>General closures</strong> are the base case. When the function object is created, its parent is set to the first object on the scope chain. When a name is evaluated that doesn't refer to a local variable, the interpreter consults the scope chain to find the variable. When <code>with</code> or <code>eval</code> are used, we have to do this for correctness.</p> - -<p>This is slow, not only because walking the scope chain is a drag, but also because we'd rather avoid actually creating the scope chain at all, if possible. General closures force the interpreter to verify the whole scope chain. So we optimize this when we can.</p> - -<p>These optimizations depend on being <em>sure</em> that we will never have to walk the scope chain, so <code>with</code> and <code>eval</code> inhibit them all.</p> - -<p><strong>Null closures.</strong> If we can prove at compile time that a function does not refer to any locals or arguments of enclosing functions, it is a null closure. Since it will never need to walk the scope chain, its parent is the global object. This is the best case. Barring <code>with</code> and <code>eval</code>, all outermost functions are null closures.</p> - -<p><strong>Null closures with upvars.</strong> A nested function is <em>algol-like</em> if it is only ever defined and called, and it isn't accessed in any other way (and it is not a generator-function). Such a function is guaranteed never to be called again after the enclosing function exits. An algol-like function may read the local variables and arguments of its immediate enclosing function from the stack, as if by magic. (<code>JSContext::display</code> caches the enclosing function's stack frame.) If that function is also algol-like, its child can read locals and variables from the next enclosing function, and so on. The compiler detects these cases and makes such functions null closures too.</p> - -<p><strong>Flat closures.</strong> Suppose a function reads some variables from enclosing functions but is not algol-like. If the function does not assign to any closed-on vars/args, and it only reads closed-on local variables and arguments that never change value after the function is created, then the function can be implemented as a flat closure. When a flat closure is created, all the closed-on values are copied from the stack into reserved slots of the function object. To evaluate a name, instead of walking the scope chain, we just take the value from the reserved slot. The function object's parent is the global object.</p> - -<p><strong>Flat closures </strong><strong>and Null closures have been <span id="summary_alias_container"><span id="short_desc_nonedit_display">removed</span></span></strong>:</p> - -<p><a href="https://bugzilla.mozilla.org/show_bug.cgi?id=730497">https://bugzilla.mozilla.org/show_bug.cgi?id=730497</a></p> - -<p><a href="https://bugzilla.mozilla.org/show_bug.cgi?id=739808">https://bugzilla.mozilla.org/show_bug.cgi?id=739808</a></p> - -<h2 id="Name_lookups">Name lookups</h2> - -<p>In order of speed, fastest to slowest.</p> - -<ol> - <li> - <p><code><strong>ARG</strong></code><strong> and <code>LOCAL</code> instructions.</strong> If a name definitely refers to an argument or local variable of the immediately enclosing function, it can be accessed using <code>JSOP_{GET,SET,CALL}</code><code>{ARG,LOCAL}</code> instructions. Some of these can even be fused with other operations into combo instructions like <code>JSOP_GETARGPROP</code>, <code>JSOP_FORLOCAL</code>, and <code>JSOP_INCLOCAL</code>. Because arguments and locals can't be deleted, this optimization is available to all functions, and <code>eval</code> does not interfere with it. But a <code>with</code> block can:</p> - - <pre>function f(s) { - eval(s); - print(s); // s can be loaded with GETARG - with (obj) { - print(s); // no GETARG here; s might refer to obj.s - } -} -</pre> - </li> - <li> - <p><code><strong>UPVAR</strong></code><strong> instructions.</strong> JSOP_{GET,CALL}UPVAR (in algol-like functions only, I think?) TODO</p> - </li> - <li> - <p><code><strong>DSLOT</strong></code><strong> instructions.</strong> JSOP_{GET,CALL}DSLOT (in flat closures only) TODO</p> - </li> - <li> - <p><code><strong>GVAR</strong></code><strong> instructions.</strong> Outside all functions, if a name definitely refers to a global for which we have seen a var, <code>const</code>, or <code>function</code> declaration, then we emit a JS_DEFVAR instruction in the script prelude and access the global using <code>JSOP_{GET,SET,CALL}GVAR</code>. This is fast if the global either doesn't exist before the script runs (the script creates it) or it's a non-configurable data property (which amounts to the same thing). Otherwise the <code>GVAR</code> instructions are as slow as <code>NAME</code> instructions.</p> - - <p>There are also combo instructions <code>JSOP_{INC,DEC}GVAR</code> and <code>JSOP_GVAR{INC,DEC}</code>.</p> - </li> - <li> - <p><code><strong>NAME</strong></code><strong> instructions.</strong> In the worst case we emit <code>JSOP_{,SET,CALL}NAME</code>. These are totally general. They can still be optimized via the property cache; in the worst case we walk the scope chain.</p> - - <p>In some cases, the JIT can optimize a <code>JSOP_NAME</code> instruction that refers to a variable in an enclosing scope to pull the value directly out of the <code>Call</code> object's <code>dslots</code>.</p> - - <p>For the expression <code>delete name</code> we always emit <code>JSOP_DELNAME</code>. It's not worth optimizing.</p> - </li> -</ol> diff --git a/files/zh-cn/mozilla/projects/spidermonkey/internals/index.html b/files/zh-cn/mozilla/projects/spidermonkey/internals/index.html deleted file mode 100644 index 03228c312f..0000000000 --- a/files/zh-cn/mozilla/projects/spidermonkey/internals/index.html +++ /dev/null @@ -1,292 +0,0 @@ ---- -title: SpiderMonkey Internals -slug: Mozilla/Projects/SpiderMonkey/Internals -tags: - - Guide - - JavaScript - - NeedsMarkupWork - - NeedsTranslation - - SpiderMonkey - - TopicStub -translation_of: Mozilla/Projects/SpiderMonkey/Internals ---- -<h2 id="Design_walk-through" name="Design_walk-through">Design walk-through</h2> - -<p>At heart, SpiderMonkey is a fast interpreter that runs an untyped bytecode and operates on values of type <code><a href="/en-US/docs/SpiderMonkey/JSAPI_Reference/Jsval" title="SpiderMonkey/JSAPI_Reference/Jsval">jsval</a></code>—type-tagged double-sized values that represent the full range of JavaScript values. In addition to the interpreter, SpiderMonkey contains a Just-In-Time (JIT) compiler, a garbage collector, code implementing the basic behavior of JavaScript values, a standard library implementing <span class="pl-s1"><span class="pl-s">ECMA 262-3 §</span></span>15 with various extensions, and a few public APIs.</p> - -<h3 id="Interpreter">Interpreter</h3> - -<p>Like many portable interpreters, SpiderMonkey's interpreter is mainly a single, tremendously long function that steps through the bytecode one instruction at a time, using a <code>switch</code> statement (or faster alternative, depending on the compiler) to jump to the appropriate chunk of code for the current instruction. A JS-to-JS function call pushes a JavaScript stack frame without growing the C stack. But since JS-to-C-to-JS call stacks are common, the interpreter is reentrant.</p> - -<p>Some SpiderMonkey bytecode operations have many special cases, depending on the type of their arguments. Common cases are inlined in the interpreter loop, breaking any abstractions that stand in the way. So optimizations such as dense arrays and the property cache are, alas, <em>not</em> transparently tucked away in the <code>jsarray.*</code> and <code>jsobj.*</code> files. Both guest-star in <code>jsinterp.cpp</code> (to thunderous applause from Firefox users).</p> - -<p>All state associated with an interpreter instance is passed through formal parameters to the interpreter entry point; most implicit state is collected in a type named <code><a href="/en-US/docs/SpiderMonkey/JSAPI_Reference/JSRuntime" title="SpiderMonkey/JSAPI_Reference/JSRuntime">JSContext</a></code>. Therefore, almost all functions in SpiderMonkey, API or not, take a <code>JSContext</code> pointer as their first argument.</p> - -<h3 id="Compiler">Compiler</h3> - -<p>The compiler consumes JavaScript source code and produces a <em>script</em> which contains bytecode, source annotations, and a pool of string, number, and identifier literals. The script also contains objects, including any functions defined in the source code, each of which has its own, nested script.</p> - -<p>The compiler consists of: a random-logic rather than table-driven lexical scanner, a recursive-descent parser that produces an AST, and a tree-walking code generator. Semantic and lexical feedback are used to disambiguate hard cases such as missing semicolons, assignable expressions ("lvalues" in C parlance), and whether <code>/</code> is the division symbol or the start of a regular expression. The compiler attempts no error recovery; it bails out on the first error. The emitter does some constant folding and a few codegen optimizations; about the fanciest thing it does is to attach source notes to the script for the decompiler's benefit.</p> - -<p>The decompiler implements <code>Function.toSource()</code>, which reconstructs a function's source code. It translates postfix bytecode into infix source by consulting a separate byte-sized code, called <em>source notes</em>, to disambiguate bytecodes that result from more than one grammatical production.</p> - -<h3 id="Garbage_collector">Garbage collector</h3> - -<p>The GC is a mark-and-sweep, non-conservative (exact) collector. It is used to hold JS objects and string descriptors (but not property lists or string bytes), and double-precision floating point numbers. It runs automatically only when maxbytes (as passed to <code><a href="/en-US/docs/SpiderMonkey/JSAPI_Reference/JS_NewRuntime" title="SpiderMonkey/JSAPI_Reference/JS_NewRuntime">JS_NewRuntime</a></code>) bytes of GC things have been allocated and another thing-allocation request is made. JS API users should call <code><a href="/en-US/docs/SpiderMonkey/JSAPI_Reference/JS_GC" title="SpiderMonkey/JSAPI_Reference/JS_GC">JS_GC</a></code> or <code><a href="/en-US/docs/SpiderMonkey/JSAPI_Reference/JS_MaybeGC" title="SpiderMonkey/JSAPI_Reference/JS_MaybeGC">JS_MaybeGC</a></code> between script executions or from the <a href="/en-US/docs/SpiderMonkey/JSAPI_Reference/JS_SetBranchCallback" title="SpiderMonkey/JSAPI_Reference/JS_SetBranchCallback">branch callback</a>, as often as necessary.</p> - -<p>Because the GC is exact, C/C++ applications must ensure that all live objects, strings, and numbers are GC-reachable. Many techniques are available; see <a href="/en-US/docs/SpiderMonkey_Garbage_Collection_Tips" title="SpiderMonkey_Garbage_Collection_Tips">SpiderMonkey Garbage Collection Tips</a>.</p> - -<h3 id="JavaScript_values">JavaScript values</h3> - -<p>The type <code><a href="/en-US/docs/SpiderMonkey/JSAPI_Reference/Jsval" title="SpiderMonkey/JSAPI_Reference/Jsval">jsval</a></code> represents a JavaScript value.</p> - -<p>The representation is 64 bits and uses NaN-boxing on all platforms, although the exact NaN-boxing format depends on the platform. NaN-boxing is a technique based on the fact that in IEEE-754 there are 2**47 different bit patterns that all represent NaN. Hence, we can encode any floating-point value as a C++ <code>double </code>(noting that JavaScript NaN must be represented as one canonical NaN format). Other values are encoded as a value and a type tag:</p> - -<ul> - <li>On x86, ARM, and similar 32-bit platforms, we use what we call "nunboxing", in which non-<code>double </code>values are a 32-bit type tag and a 32-bit payload, which is normally either a pointer or a signed 32-bit integer. There are a few special values: <code><a href="/en-US/docs/SpiderMonkey/JSAPI_Reference/JSVAL_NULL" title="SpiderMonkey/JSAPI_Reference/JSVAL_NULL">JSVAL_NULL</a></code>, <code><a href="/en-US/docs/SpiderMonkey/JSAPI_Reference/JSVAL_VOID" title="SpiderMonkey/JSAPI_Reference/JSVAL_VOID">JSVAL_VOID</a></code> (<code>undefined</code>), <code><a href="/en-US/docs/SpiderMonkey/JSAPI_Reference/JSVAL_TRUE" title="SpiderMonkey/JSAPI_Reference/JSVAL_TRUE">JSVAL_TRUE</a></code>, and <code><a href="/en-US/docs/JSVAL_FALSE" title="JSVAL_FALSE">JSVAL_FALSE</a></code>. Another special value, <code><a href="/en-US/docs/JSVAL_HOLE" title="JSVAL_HOLE">JSVAL_HOLE</a></code>, is used internally only (to represent deleted <code>Array</code> elements, for example). This value is never exposed to scripts or even via the JSAPI.</li> - <li>On x64 and similar 64-bit platforms, pointers are longer than 32 bits, so we can't use the nunboxing format. Instead, we use "punboxing", which has 17 bits of tag and 47 bits of payload.</li> -</ul> - -<p>Only JIT code really depends on the layout--everything else in the engine interacts with values through functions like <code>JSVAL_IS_INT</code>. Most parts of the JIT also avoid depending directly on the layout: the files <code>PunboxAssembler.h</code> and <code>NunboxAssembler.h</code> are used to generate native code that depends on the value layout.</p> - -<p>Objects consist of a possibly shared structural description, called the map or scope; and unshared property values in a vector, called the slots. Each property has an <a href="/en-US/docs/SpiderMonkey/JSAPI_Reference/jsid" title="SpiderMonkey/JSAPI_Reference/jsid">id</a>, either a nonnegative integer or an atom (unique string), with the same tagged-pointer encoding as a <code>jsval</code>.</p> - -<p>The atom manager consists of a hash table associating strings uniquely with scanner/parser information such as keyword type, index in script or function literal pool, etc. Atoms play three roles: as literals referred to by unaligned 16-bit immediate bytecode operands, as unique string descriptors for efficient property name hashing, and as members of the root GC set for exact GC.</p> - -<h3 id="Standard_library">Standard library</h3> - -<p>The methods for arrays, booleans, dates, functions, numbers, and strings are implemented using the JS API. Most are <code><a href="https://developer.mozilla.org/en-US/docs/Mozilla/Projects/SpiderMonkey/JSAPI_reference/JSNative" title="SpiderMonkey/JSAPI_Reference/JSFastNative">JSNative</a></code>s. Most string methods are customized to accept a primitive string as the <code>this</code> argument. (Otherwise, SpiderMonkey converts primitive values to objects before invoking their methods, per <span class="pl-s1"><span class="pl-s">ECMA 262-3 §</span></span>11.2.1.)</p> - -<h3 id="Error_handling">Error handling</h3> - -<p>SpiderMonkey has two interdependent error-handling systems: JavaScript exceptions (which are <em>not</em> implemented with, or even compatible with, any kind of native C/C++ exception handling) and error reporting. In general, both functions inside SpiderMonkey and JSAPI callback functions signal errors by calling <code><a href="/en-US/docs/SpiderMonkey/JSAPI_Reference/JS_ReportError" title="SpiderMonkey/JSAPI_Reference/JS_ReportError">JS_ReportError</a></code> or one of its variants, or <code><a href="/en-US/docs/SpiderMonkey/JSAPI_Reference/JS_SetPendingException" title="SpiderMonkey/JSAPI_Reference/JS_SetPendingException">JS_SetPendingException</a></code>, and returning <code><a href="/en-US/docs/SpiderMonkey/JSAPI_Reference/JSBool" title="SpiderMonkey/JSAPI_Reference/JSBool">JS_FALSE</a></code> or <code>NULL</code>.</p> - -<h3 id="Public_APIs">Public APIs</h3> - -<p>The public C/C++ interface, called the JSAPI, is in most places a thin (but source-compatible across versions) layer over the implementation. See the <a href="/en-US/docs/SpiderMonkey/JSAPI_User_Guide" title="JSAPI_User_Guide">JSAPI User Guide</a>. There is an additional public API for JavaScript debuggers, <a href="/en-US/docs/JSDBGAPI_Reference" title="JSDBGAPI_Reference">JSDBGAPI</a>, but {{Source("js/jsd/jsdebug.h")}} might be a better API for debuggers. Another API, <a href="/en-US/docs/JSXDRAPI" title="JSXDRAPI">JSXDRAPI</a>, provides serialization for JavaScript scripts. (XUL Fastload uses this.)</p> - -<h3 id="Just-In-Time_compiler">Just-In-Time compiler</h3> - -<p>{{jsapi_minversion_inline("1.8.5")}} SpiderMonkey contains a just-in-time compiler, code-named <em>JägerMonkey</em>, that converts bytecode to machine code for faster execution. The JIT works by detecting commonly executed functions or functions containing hot loops and then compiling these methods into machine code.</p> - -<p>A second JIT, code-named <em>IonMonkey</em> was enabled in <a href="https://blog.mozilla.org/javascript/2012/09/12/ionmonkey-in-firefox-18/" title="https://blog.mozilla.org/javascript/2012/09/12/ionmonkey-in-firefox-18/">Firefox 18</a>.</p> - -<h3 id="Self-hosting_of_builtin_functions_in_JS">Self-hosting of builtin functions in JS</h3> - -<p>Starting with Firefox 17, SpiderMonkey has the ability to implement builtin functions in self-hosted JS code. This code is compiled in a special compilation mode that gives it access to functionality that's not normally exposed to JS code, but that's required for safe and specification-conformant implementation of builtin functions.</p> - -<p>All self-hosted code lives in <code>.js</code> files under <code>builtin/</code>. For details on implementing self-hosted builtins, see <a href="/en-US/docs/SpiderMonkey/Internals/self-hosting" title="SpiderMonkey/self-hosting">self-hosting</a>.</p> - -<h2 id="File_walkthrough" name="File_walkthrough">File walkthrough</h2> - -<h4 id="jsapi.cpp.2C_jsapi.h" name="jsapi.cpp.2C_jsapi.h">jsapi.cpp, jsapi.h</h4> - -<p>The public API to be used by almost all client code.</p> - -<h4 id="jspubtd.h.2C_jsprvtd.h" name="jspubtd.h.2C_jsprvtd.h">jspubtd.h, jsprvtd.h</h4> - -<p>These files exist to group struct and scalar typedefs so they can be used everywhere without dragging in struct definitions from N different files. The <code>jspubtd.h</code> file contains public typedefs, and is included automatically when needed. The <code>jsprvtd.h</code> file contains private typedefs and is included by various .h files that need type names, but not type sizes or declarations.</p> - -<h4 id="jsdbgapi.cpp.2C_jsdbgapi.h" name="jsdbgapi.cpp.2C_jsdbgapi.h">jsdbgapi.cpp, jsdbgapi.h</h4> - -<p>The debugging API. Provided so far:</p> - -<p><strong>Traps</strong>, with which breakpoints, single-stepping, step over, step out, and so on can be implemented. The debugger will have to consult jsopcode.def on its own to figure out where to plant trap instructions to implement functions like step out, but a future jsdbgapi.h will provide convenience interfaces to do these things. At most one trap per bytecode can be set. When a script (<code><a href="/en-US/docs/JSScript" title="JSScript">JSScript</a></code>) is destroyed, all traps set in its bytecode are cleared.</p> - -<p><strong>Watchpoints</strong>, for intercepting set operations on properties and running a debugger-supplied function that receives the old value and a pointer to the new one, which it can use to modify the new value being set.</p> - -<p><strong>Line number</strong> to PC and back mapping functions. The line-to-PC direction "rounds" toward the next bytecode generated from a line greater than or equal to the input line, and may return the PC of a for-loop update part, if given the line number of the loop body's closing brace. Any line after the last one in a script or function maps to a PC one byte beyond the last bytecode in the script. An example, from perfect.js:</p> - -<pre class="brush:js;first-line:14">function perfect(n) { - print("The perfect numbers up to " + n + " are:"); - // We build sumOfDivisors[i] to hold a string expression for - // the sum of the divisors of i, excluding i itself. - var sumOfDivisors = new ExprArray(n+1,1); - for (var divisor = 2; divisor <= n; divisor++) { - for (var j = divisor + divisor; j <= n; j += divisor) { - sumOfDivisors[j] += " + " + divisor; - } - // At this point everything up to 'divisor' has its sumOfDivisors - // expression calculated, so we can determine whether it's perfect - // already by evaluating. - if (eval(sumOfDivisors[divisor]) == divisor) { - print("" + divisor + " = " + sumOfDivisors[divisor]); - } - } - delete sumOfDivisors; - print("That's all."); -}</pre> - -<p>The line number to PC and back mappings can be tested using the js program with the following script:</p> - -<pre class="brush:js">load("perfect.js"); -print(perfect); -dis(perfect); -print(); -for (var ln = 0; ln <= 40; ln++) { - var pc = line2pc(perfect, ln); - var ln2 = pc2line(perfect, pc); - print("\tline " + ln + " => pc " + pc + " => line " + ln2); -} -</pre> - -<p>The result of the for loop over lines 0 to 40 inclusive is:</p> - -<pre>line 0 => pc 0 => line 16 -line 1 => pc 0 => line 16 -line 2 => pc 0 => line 16 -line 3 => pc 0 => line 16 -line 4 => pc 0 => line 16 -line 5 => pc 0 => line 16 -line 6 => pc 0 => line 16 -line 7 => pc 0 => line 16 -line 8 => pc 0 => line 16 -line 9 => pc 0 => line 16 -line 10 => pc 0 => line 16 -line 11 => pc 0 => line 16 -line 12 => pc 0 => line 16 -line 13 => pc 0 => line 16 -line 14 => pc 0 => line 16 -line 15 => pc 0 => line 16 -line 16 => pc 0 => line 16 -line 17 => pc 19 => line 20 -line 18 => pc 19 => line 20 -line 19 => pc 19 => line 20 -line 20 => pc 19 => line 20 -line 21 => pc 36 => line 21 -line 22 => pc 53 => line 22 -line 23 => pc 74 => line 23 -line 24 => pc 92 => line 22 -line 25 => pc 106 => line 28 -line 26 => pc 106 => line 28 -line 27 => pc 106 => line 28 -line 28 => pc 106 => line 28 -line 29 => pc 127 => line 29 -line 30 => pc 154 => line 21 -line 31 => pc 154 => line 21 -line 32 => pc 161 => line 32 -line 33 => pc 172 => line 33 -line 34 => pc 172 => line 33 -line 35 => pc 172 => line 33 -line 36 => pc 172 => line 33 -line 37 => pc 172 => line 33 -line 38 => pc 172 => line 33 -line 39 => pc 172 => line 33 -line 40 => pc 172 => line 33 -</pre> - -<h4 id="jsconfig.h" name="jsconfig.h">jsconfig.h</h4> - -<p>Various configuration macros defined as 0 or 1 depending on how <code><a href="/en-US/docs/JS_VERSION" title="JS_VERSION">JS_VERSION</a></code> is defined (as 10 for JavaScript 1.0, 11 for JavaScript 1.1, etc.). Not all macros are tested around related code yet. In particular, JS 1.0 support is missing from SpiderMonkey.</p> - -<h4 id="js.cpp.2C_jsshell.msg" name="js.cpp.2C_jsshell.msg">js.cpp, jsshell.msg</h4> - -<p>The "JS shell", a simple interpreter program that uses the JS API and more than a few internal interfaces (some of these internal interfaces could be replaced by <code>jsapi.h</code> calls). The js program built from this source provides a test vehicle for evaluating scripts and calling functions, trying out new debugger primitives, etc.</p> - -<p>A look at the places where <code>jsshell.msg</code> is used in <code>js.cpp</code> shows how error messages can be handled in JSAPI applications. These messages can be localized at compile time by replacing the <code>.msg</code> file; or, with a little modification to the source, at run time.</p> - -<p><a href="/en-US/docs/SpiderMonkey/Introduction_to_the_JavaScript_shell" title="https://developer.mozilla.org/en/introduction_to_the_javascript_shell">More information on the JavaScript shell</a>.</p> - -<h4 id="js.msg" name="js.msg">js.msg</h4> - -<p>SpiderMonkey error messages.</p> - -<h4 id="jsarray..2A.2C_jsbool..2A.2C_jdsdate..2A.2C_jsfun..2A.2C_jsmath..2A.2C_jsnum..2A.2C_jsstr..2A" name="jsarray..2A.2C_jsbool..2A.2C_jdsdate..2A.2C_jsfun..2A.2C_jsmath..2A.2C_jsnum..2A.2C_jsstr..2A">jsarray.*, jsbool.*, jsdate.*, jsfun.*, jsmath.*, jsnum.*, jsstr.*</h4> - -<p>These file pairs implement the standard classes and (where they exist) their underlying primitive types. They have similar structure, generally starting with class definitions and continuing with internal constructors, finalizers, and helper functions.</p> - -<h4 id="jsobj..2A.2C_jsscope..2A" name="jsobj..2A.2C_jsscope..2A">jsobj.*, jsscope.*</h4> - -<p>These two pairs declare and implement the JS object system. All of the following happen here:</p> - -<ul> - <li>creating objects by class and prototype, and finalizing objects;</li> - <li>defining, looking up, getting, setting, and deleting properties;</li> - <li>creating and destroying properties and binding names to them.</li> -</ul> - -<p>The details of a native object's map (scope) are mostly hidden in <code>jsscope.{{mediawiki.external('ch')}}</code>.</p> - -<h4 id="jsatom.cpp.2C_jsatom.h" name="jsatom.cpp.2C_jsatom.h">jsatom.cpp, jsatom.h</h4> - -<p>The atom manager. Contains well-known string constants, their atoms, the global atom hash table and related state, the js_Atomize() function that turns a counted string of bytes into an atom, and literal pool (<code>JSAtomMap</code>) methods.</p> - -<h4 id="jsarena.cpp.2C_jsarena.h" name="jsarena.cpp.2C_jsarena.h">jsarena.cpp, jsarena.h</h4> - -<p>Last-In-First-Out allocation macros that amortize malloc costs and allow for en-masse freeing. See the paper mentioned in <code>jsarena.h</code>'s major comment.</p> - -<h4 id="jsgc.cpp.2C_jsgc.h" name="jsgc.cpp.2C_jsgc.h">jsgc.cpp, jsgc.h</h4> - -<p>The garbage collector and tracing routines.</p> - -<h4 id="jsinterp..2A.2C_jscntxt..2A.2C_jsinvoke.cpp" name="jsinterp..2A.2C_jscntxt..2A.2C_jsinvoke.cpp">jsinterp.*, jscntxt.*, jsinvoke.cpp</h4> - -<p>The bytecode interpreter, and related functions such as Call and AllocStack, live in <em>jsinterp.cpp</em>. The JSContext constructor and destructor are factored out into <em>jscntxt.cpp</em> for minimal linking when the compiler part of JS is split from the interpreter part into a separate program.</p> - -<p><code>jsinvoke.cpp</code> is a build hack used on some platforms to build <code>js_Interpret</code> under different compiler options from the rest of <code>jsinterp.cpp</code>.</p> - -<h4 id="jstracer.*_nanojit*">jstracer.*, nanojit/*</h4> - -<p><a href="/en-US/docs/SpiderMonkey/Internals/Tracing_JIT" title="SpiderMonkey/Internals/Tracing JIT">The tracing JIT</a>. The interface between the JIT and the rest of SpiderMonkey is conceptually small—the interpreter calls into the trace recorder—but as with everything else, there are tendrils everywhere.</p> - -<h4 id="jsemit..2A.2C_jsopcode.tbl.2C_jsopcode..2A.2C_jsparse..2A.2C_jsscan..2A.2C_jsscript..2A" name="jsemit..2A.2C_jsopcode.tbl.2C_jsopcode..2A.2C_jsparse..2A.2C_jsscan..2A.2C_jsscript..2A">jsemit.*, jsopcode.tbl, jsopcode.*, jsparse.*, jsscan.*, jsscript.*</h4> - -<p>Compiler and decompiler modules. The <em>jsopcode.tbl</em> file is a C preprocessor source that defines almost everything there is to know about JS bytecodes. See its major comment for how to use it. For now, a debugger will use it and its dependents such as <em>jsopcode.h</em> directly, but over time we intend to extend <em>jsdbgapi.h</em> to hide uninteresting details and provide conveniences. The code generator is split across paragraphs of code in <em>jsparse.cpp</em>, and the utility methods called on <code>JSCodeGenerator</code> appear in <em>jsemit.cpp</em>. Source notes generated by <em>jsparse.cpp</em> and <em>jsemit.cpp</em> are used in <em>jsscript.cpp</em> to map line number to program counter and back.</p> - -<h4 id="jstypes.h" name="jstypes.h">jstypes.h</h4> - -<p>Fundamental representation types and utility macros. This file alone among all .h files in SpiderMonkey must be included first by .cpp files. It is not nested in .h files, as other prerequisite .h files generally are, since it is also a direct dependency of most .cpp files and would be over-included if nested in addition to being directly included.</p> - -<h4 id="jsbit.h.2C_jslog2.cpp" name="jsbit.h.2C_jslog2.cpp">jsbit.h, jslog2.cpp</h4> - -<p>Bit-twiddling routines. Most of the work here is selectively enabling compiler-specific intrinsics such as GCC's <code>__builtin_ctz</code>, which is useful in calculating base-2 logarithms of integers.</p> - -<h4 id="jsutil.cpp.2C_jsutil.h" name="jsutil.cpp.2C_jsutil.h">jsutil.cpp, jsutil.h</h4> - -<p>The <code>JS_ASSERT</code> macro is used throughout the source as a proof device to make invariants and preconditions clear to the reader, and to hold the line during maintenance and evolution against regressions or violations of assumptions that it would be too expensive to test unconditionally at run-time. Certain assertions are followed by run-time tests that cope with assertion failure, but only where I'm too smart or paranoid to believe the assertion will never fail...</p> - -<h4 id="jsclist.h" name="jsclist.h">jsclist.h</h4> - -<p>Doubly-linked circular list struct and macros.</p> - -<h4 id="jscpucfg.cpp" name="jscpucfg.cpp">jscpucfg.cpp</h4> - -<p>This standalone program generates <em>jscpucfg.h</em>, a header file containing bytes per word and other constants that depend on CPU architecture and C compiler type model. It tries to discover most of these constants by running its own experiments on the build host, so if you are cross-compiling, beware.</p> - -<h4 id="jsdtoa.cpp.2C_jsdtoa.h.2C_dtoa.c" name="jsdtoa.cpp.2C_jsdtoa.h.2C_dtoa.c">jsdtoa.cpp, jsdtoa.h, dtoa.c</h4> - -<p>dtoa.c contains David Gay's portable double-precision floating point to string conversion code, with Permission To Use notice included. jsdtoa.cpp <code>#include</code>s this file.</p> - -<h4 id="jshash.cpp.2C_jshash.h.2C_jsdhash.cpp.2C_jsdhash.h" name="jshash.cpp.2C_jshash.h.2C_jsdhash.cpp.2C_jsdhash.h">jshash.cpp, jshash.h, jsdhash.cpp, jsdhash.h</h4> - -<p>Portable, extensible hash tables. These use multiplicative hash for strength reduction over division hash, yet with very good key distribution over power of two table sizes. jshash resolves collisions via chaining, so each entry burns a malloc and can fragment the heap. jsdhash uses open addressing.</p> - -<h4 id="jslong.cpp.2C_jslong.h" name="jslong.cpp.2C_jslong.h">jslong.cpp, jslong.h</h4> - -<p>64-bit integer emulation, and compatible macros that use intrinsic C types, like <code>long long</code>, on platforms where they exist (most everywhere, these days).</p> - -<h4 id="jsprf..2A" name="jsprf..2A">jsprf.*</h4> - -<p>Portable, buffer-overrun-resistant sprintf and friends. For no good reason save lack of time, the %e, %f, and %g formats cause your system's native sprintf, rather than <code>JS_dtoa()</code>, to be used. This bug doesn't affect SpiderMonkey, because it uses its own <code>JS_dtoa()</code> call in <code>jsnum.cpp</code> to convert from double to string, but it's a bug that we'll fix later, and one you should be aware of if you intend to use a <code>JS_*printf()</code> function with your own floating type arguments - various vendor sprintf's mishandle NaN, +/-Inf, and some even print normal floating values inaccurately.</p> - -<h4 id="prmjtime.c.2C_prmjtime.h" name="prmjtime.c.2C_prmjtime.h">prmjtime.c, prmjtime.h</h4> - -<p>Time functions. These interfaces are named in a way that makes local vs. universal time confusion likely. Caveat emptor, and we're working on it. To make matters worse, Java (and therefore JavaScript) uses "local" time numbers (offsets from the epoch) in its Date class.</p> - -<h4 id="jsfile.cpp.2C_jsfile.h.2C_jsfile.msg" name="jsfile.cpp.2C_jsfile.h.2C_jsfile.msg">jsfile.cpp, jsfile.h, jsfile.msg</h4> - -<p>Obsolete. Do not use these files.</p> - -<h4 id="Makefile.in.2C_build.mk" name="Makefile.in.2C_build.mk">Makefile.in, build.mk</h4> - -<p>Mozilla makefiles. If you're building Gecko or Firefox, the larger build system will use these files. They are also used for current standalone builds.</p> - -<h4 id="Makefile.ref.2C_rules.mk.2C_config.mk.2C_config.2F.2A" name="Makefile.ref.2C_rules.mk.2C_config.mk.2C_config.2F.2A">Makefile.ref, rules.mk, config.mk, config/*</h4> - -<p>Obsolete SpiderMonkey standalone makefiles from 1.8 and earlier. See <a href="/en-US/docs/SpiderMonkey/Build_Documentation#Building_SpiderMonkey_1.8_or_earlier" title="SpiderMonkey/Build Documentation#Building SpiderMonkey 1.8 or earlier">SpiderMonkey Build Documentation</a>.</p> - -<h3 id="See_also">See also</h3> - -<ul> - <li><a href="/jsd" title="jsd">jsd</a></li> -</ul> |