/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- * vim: set ts=8 sw=4 et tw=78: * * ***** BEGIN LICENSE BLOCK ***** * Version: MPL 1.1/GPL 2.0/LGPL 2.1 * * The contents of this file are subject to the Mozilla Public License Version * 1.1 (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * http://www.mozilla.org/MPL/ * * Software distributed under the License is distributed on an "AS IS" basis, * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License * for the specific language governing rights and limitations under the * License. * * The Original Code is Mozilla Communicator client code, released * March 31, 1998. * * The Initial Developer of the Original Code is * Netscape Communications Corporation. * Portions created by the Initial Developer are Copyright (C) 1998 * the Initial Developer. All Rights Reserved. * * Contributor(s): * * Alternatively, the contents of this file may be used under the terms of * either of the GNU General Public License Version 2 or later (the "GPL"), * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"), * in which case the provisions of the GPL or the LGPL are applicable instead * of those above. If you wish to allow use of your version of this file only * under the terms of either the GPL or the LGPL, and not to allow others to * use your version of this file under the terms of the MPL, indicate your * decision by deleting the provisions above and replace them with the notice * and other provisions required by the GPL or the LGPL. If you do not delete * the provisions above, a recipient may use your version of this file under * the terms of any one of the MPL, the GPL or the LGPL. * * ***** END LICENSE BLOCK ***** */ #ifndef jsinterp_h___ #define jsinterp_h___ /* * JS interpreter interface. */ #include "jsprvtd.h" #include "jspubtd.h" #include "jsfun.h" #include "jsopcode.h" #include "jsscript.h" JS_BEGIN_EXTERN_C typedef struct JSFrameRegs { jsbytecode *pc; /* program counter */ jsval *sp; /* stack pointer */ } JSFrameRegs; /* * JS stack frame, may be allocated on the C stack by native callers. Always * allocated on cx->stackPool for calls from the interpreter to an interpreted * function. * * NB: This struct is manually initialized in jsinterp.c and jsiter.c. If you * add new members, update both files. But first, try to remove members. The * sharp* and xml* members should be moved onto the stack as local variables * with well-known slots, if possible. */ struct JSStackFrame { JSFrameRegs *regs; jsbytecode *imacpc; /* null or interpreter macro call pc */ jsval *slots; /* variables, locals and operand stack */ JSObject *callobj; /* lazily created Call object */ JSObject *argsobj; /* lazily created arguments object */ JSObject *varobj; /* variables object, where vars go */ JSObject *callee; /* function or script object */ JSScript *script; /* script being interpreted */ JSFunction *fun; /* function being called or null */ JSObject *thisp; /* "this" pointer if in method */ uintN argc; /* actual argument count */ jsval *argv; /* base of argument stack slots */ jsval rval; /* function return value */ JSStackFrame *down; /* previous frame */ void *annotation; /* used by Java security */ JSObject *scopeChain; /* scope chain */ uintN sharpDepth; /* array/object initializer depth */ JSObject *sharpArray; /* scope for #n= initializer vars */ uint32 flags; /* frame flags -- see below */ JSStackFrame *dormantNext; /* next dormant frame chain */ JSObject *xmlNamespace; /* null or default xml namespace in E4X */ JSObject *blockChain; /* active compile-time block scopes */ JSStackFrame *displaySave; /* previous value of display entry for script->staticDepth */ #ifdef DEBUG jsrefcount pcDisabledSave; /* for balanced property cache control */ #endif }; #ifdef DEBUG #ifdef __cplusplus static JS_INLINE uintN FramePCOffset(JSStackFrame* fp) { return uintN((fp->imacpc ? fp->imacpc : fp->regs->pc) - fp->script->code); } #endif #endif static JS_INLINE jsval * StackBase(JSStackFrame *fp) { return fp->slots + fp->script->nfixed; } static JS_INLINE uintN GlobalVarCount(JSStackFrame *fp) { uintN n; JS_ASSERT(!fp->fun); n = fp->script->nfixed; if (fp->script->regexpsOffset != 0) n -= JS_SCRIPT_REGEXPS(fp->script)->length; return n; } typedef struct JSInlineFrame { JSStackFrame frame; /* base struct */ JSFrameRegs callerRegs; /* parent's frame registers */ void *mark; /* mark before inline frame */ void *hookData; /* debugger call hook data */ JSVersion callerVersion; /* dynamic version of calling script */ } JSInlineFrame; /* JS stack frame flags. */ #define JSFRAME_CONSTRUCTING 0x01 /* frame is for a constructor invocation */ #define JSFRAME_COMPUTED_THIS 0x02 /* frame.thisp was computed already */ #define JSFRAME_ASSIGNING 0x04 /* a complex (not simplex JOF_ASSIGNING) op is currently assigning to a property */ #define JSFRAME_DEBUGGER 0x08 /* frame for JS_EvaluateInStackFrame */ #define JSFRAME_EVAL 0x10 /* frame for obj_eval */ #define JSFRAME_ROOTED_ARGV 0x20 /* frame.argv is rooted by the caller */ #define JSFRAME_YIELDING 0x40 /* js_Interpret dispatched JSOP_YIELD */ #define JSFRAME_ITERATOR 0x80 /* trying to get an iterator for for-in */ #define JSFRAME_POP_BLOCKS 0x100 /* scope chain contains blocks to pop */ #define JSFRAME_GENERATOR 0x200 /* frame belongs to generator-iterator */ #define JSFRAME_IMACRO_START 0x400 /* imacro starting -- see jstracer.h */ #define JSFRAME_OVERRIDE_SHIFT 24 /* override bit-set params; see jsfun.c */ #define JSFRAME_OVERRIDE_BITS 8 #define JSFRAME_SPECIAL (JSFRAME_DEBUGGER | JSFRAME_EVAL) /* * Property cache with structurally typed capabilities for invalidation, for * polymorphic callsite method/get/set speedups. * * See bug https://bugzilla.mozilla.org/show_bug.cgi?id=365851. */ #define PROPERTY_CACHE_LOG2 12 #define PROPERTY_CACHE_SIZE JS_BIT(PROPERTY_CACHE_LOG2) #define PROPERTY_CACHE_MASK JS_BITMASK(PROPERTY_CACHE_LOG2) /* * Add kshape rather than xor it to avoid collisions between nearby bytecode * that are evolving an object by setting successive properties, incrementing * the object's scope->shape on each set. */ #define PROPERTY_CACHE_HASH(pc,kshape) \ (((((jsuword)(pc) >> PROPERTY_CACHE_LOG2) ^ (jsuword)(pc)) + (kshape)) & \ PROPERTY_CACHE_MASK) #define PROPERTY_CACHE_HASH_PC(pc,kshape) \ PROPERTY_CACHE_HASH(pc, kshape) #define PROPERTY_CACHE_HASH_ATOM(atom,obj,pobj) \ PROPERTY_CACHE_HASH((jsuword)(atom) >> 2, OBJ_SHAPE(obj)) /* * Property cache value capability macros. */ #define PCVCAP_PROTOBITS 4 #define PCVCAP_PROTOSIZE JS_BIT(PCVCAP_PROTOBITS) #define PCVCAP_PROTOMASK JS_BITMASK(PCVCAP_PROTOBITS) #define PCVCAP_SCOPEBITS 4 #define PCVCAP_SCOPESIZE JS_BIT(PCVCAP_SCOPEBITS) #define PCVCAP_SCOPEMASK JS_BITMASK(PCVCAP_SCOPEBITS) #define PCVCAP_TAGBITS (PCVCAP_PROTOBITS + PCVCAP_SCOPEBITS) #define PCVCAP_TAGMASK JS_BITMASK(PCVCAP_TAGBITS) #define PCVCAP_TAG(t) ((t) & PCVCAP_TAGMASK) #define PCVCAP_MAKE(t,s,p) (((t) << PCVCAP_TAGBITS) | \ ((s) << PCVCAP_PROTOBITS) | \ (p)) #define PCVCAP_SHAPE(t) ((t) >> PCVCAP_TAGBITS) #define SHAPE_OVERFLOW_BIT JS_BIT(32 - PCVCAP_TAGBITS) /* * When sprop is not null and the shape generation triggers the GC due to a * shape overflow, the functions roots sprop. */ extern uint32 js_GenerateShape(JSContext *cx, JSBool gcLocked, JSScopeProperty *sprop); struct JSPropCacheEntry { jsbytecode *kpc; /* pc if vcap tag is <= 1, else atom */ jsuword kshape; /* key shape if pc, else obj for atom */ jsuword vcap; /* value capability, see above */ jsuword vword; /* value word, see PCVAL_* below */ }; #if defined DEBUG_brendan || defined DEBUG_brendaneich #define JS_PROPERTY_CACHE_METERING 1 #endif typedef struct JSPropertyCache { JSPropCacheEntry table[PROPERTY_CACHE_SIZE]; JSBool empty; jsrefcount disabled; /* signed for anti-underflow asserts */ #ifdef JS_PROPERTY_CACHE_METERING uint32 fills; /* number of cache entry fills */ uint32 nofills; /* couldn't fill (e.g. default get) */ uint32 rofills; /* set on read-only prop can't fill */ uint32 disfills; /* fill attempts on disabled cache */ uint32 oddfills; /* fill attempt after setter deleted */ uint32 modfills; /* fill that rehashed to a new entry */ uint32 brandfills; /* scope brandings to type structural method fills */ uint32 noprotos; /* resolve-returned non-proto pobj */ uint32 longchains; /* overlong scope and/or proto chain */ uint32 recycles; /* cache entries recycled by fills */ uint32 pcrecycles; /* pc-keyed entries recycled by atom- keyed fills */ uint32 tests; /* cache probes */ uint32 pchits; /* fast-path polymorphic op hits */ uint32 protopchits; /* pchits hitting immediate prototype */ uint32 initests; /* cache probes from JSOP_INITPROP */ uint32 inipchits; /* init'ing next property pchit case */ uint32 inipcmisses; /* init'ing next property pc misses */ uint32 settests; /* cache probes from JOF_SET opcodes */ uint32 addpchits; /* adding next property pchit case */ uint32 setpchits; /* setting existing property pchit */ uint32 setpcmisses; /* setting/adding property pc misses */ uint32 slotchanges; /* clasp->reserveSlots result variance- induced slot changes */ uint32 setmisses; /* JSOP_SET{NAME,PROP} total misses */ uint32 idmisses; /* slow-path key id == atom misses */ uint32 komisses; /* slow-path key object misses */ uint32 vcmisses; /* value capability misses */ uint32 misses; /* cache misses */ uint32 flushes; /* cache flushes */ uint32 pcpurges; /* shadowing purges on proto chain */ # define PCMETER(x) x #else # define PCMETER(x) ((void)0) #endif } JSPropertyCache; /* * Property cache value tagging/untagging macros. */ #define PCVAL_OBJECT 0 #define PCVAL_SLOT 1 #define PCVAL_SPROP 2 #define PCVAL_TAGBITS 2 #define PCVAL_TAGMASK JS_BITMASK(PCVAL_TAGBITS) #define PCVAL_TAG(v) ((v) & PCVAL_TAGMASK) #define PCVAL_CLRTAG(v) ((v) & ~(jsuword)PCVAL_TAGMASK) #define PCVAL_SETTAG(v,t) ((jsuword)(v) | (t)) #define PCVAL_NULL 0 #define PCVAL_IS_NULL(v) ((v) == PCVAL_NULL) #define PCVAL_IS_OBJECT(v) (PCVAL_TAG(v) == PCVAL_OBJECT) #define PCVAL_TO_OBJECT(v) ((JSObject *) (v)) #define OBJECT_TO_PCVAL(obj) ((jsuword) (obj)) #define PCVAL_OBJECT_TO_JSVAL(v) OBJECT_TO_JSVAL(PCVAL_TO_OBJECT(v)) #define JSVAL_OBJECT_TO_PCVAL(v) OBJECT_TO_PCVAL(JSVAL_TO_OBJECT(v)) #define PCVAL_IS_SLOT(v) ((v) & PCVAL_SLOT) #define PCVAL_TO_SLOT(v) ((jsuint)(v) >> 1) #define SLOT_TO_PCVAL(i) (((jsuword)(i) << 1) | PCVAL_SLOT) #define PCVAL_IS_SPROP(v) (PCVAL_TAG(v) == PCVAL_SPROP) #define PCVAL_TO_SPROP(v) ((JSScopeProperty *) PCVAL_CLRTAG(v)) #define SPROP_TO_PCVAL(sprop) PCVAL_SETTAG(sprop, PCVAL_SPROP) /* * Fill property cache entry for key cx->fp->pc, optimized value word computed * from obj and sprop, and entry capability forged from 24-bit OBJ_SHAPE(obj), * 4-bit scopeIndex, and 4-bit protoIndex. */ extern void js_FillPropertyCache(JSContext *cx, JSObject *obj, jsuword kshape, uintN scopeIndex, uintN protoIndex, JSObject *pobj, JSScopeProperty *sprop, JSPropCacheEntry **entryp); /* * Property cache lookup macros. PROPERTY_CACHE_TEST is designed to inline the * fast path in js_Interpret, so it makes "just-so" restrictions on parameters, * e.g. pobj and obj should not be the same variable, since for JOF_PROP-mode * opcodes, obj must not be changed because of a cache miss. * * On return from PROPERTY_CACHE_TEST, if atom is null then obj points to the * scope chain element in which the property was found, pobj is locked, and * entry is valid. If atom is non-null then no object is locked but entry is * still set correctly for use, e.g., by js_FillPropertyCache and atom should * be used as the id to find. * * We must lock pobj on a hit in order to close races with threads that might * be deleting a property from its scope, or otherwise invalidating property * caches (on all threads) by re-generating scope->shape. */ #define PROPERTY_CACHE_TEST(cx, pc, obj, pobj, entry, atom) \ do { \ JSPropertyCache *cache_ = &JS_PROPERTY_CACHE(cx); \ uint32 kshape_ = (JS_ASSERT(OBJ_IS_NATIVE(obj)), OBJ_SHAPE(obj)); \ entry = &cache_->table[PROPERTY_CACHE_HASH_PC(pc, kshape_)]; \ PCMETER(cache_->tests++); \ JS_ASSERT(&obj != &pobj); \ if (entry->kpc == pc && entry->kshape == kshape_) { \ JSObject *tmp_; \ pobj = obj; \ JS_LOCK_OBJ(cx, pobj); \ JS_ASSERT(PCVCAP_TAG(entry->vcap) <= 1); \ if (PCVCAP_TAG(entry->vcap) == 1 && \ (tmp_ = LOCKED_OBJ_GET_PROTO(pobj)) != NULL && \ OBJ_IS_NATIVE(tmp_)) { \ JS_UNLOCK_OBJ(cx, pobj); \ pobj = tmp_; \ JS_LOCK_OBJ(cx, pobj); \ } \ if (PCVCAP_SHAPE(entry->vcap) == OBJ_SHAPE(pobj)) { \ PCMETER(cache_->pchits++); \ PCMETER(!PCVCAP_TAG(entry->vcap) || cache_->protopchits++); \ pobj = OBJ_SCOPE(pobj)->object; \ atom = NULL; \ break; \ } \ JS_UNLOCK_OBJ(cx, pobj); \ } \ atom = js_FullTestPropertyCache(cx, pc, &obj, &pobj, &entry); \ if (atom) \ PCMETER(cache_->misses++); \ } while (0) extern JSAtom * js_FullTestPropertyCache(JSContext *cx, jsbytecode *pc, JSObject **objp, JSObject **pobjp, JSPropCacheEntry **entryp); extern void js_FlushPropertyCache(JSContext *cx); extern void js_FlushPropertyCacheForScript(JSContext *cx, JSScript *script); extern void js_DisablePropertyCache(JSContext *cx); extern void js_EnablePropertyCache(JSContext *cx); /* * Interpreter stack arena-pool alloc and free functions. */ extern JS_FRIEND_API(jsval *) js_AllocStack(JSContext *cx, uintN nslots, void **markp); extern JS_FRIEND_API(void) js_FreeStack(JSContext *cx, void *mark); /* * Refresh and return fp->scopeChain. It may be stale if block scopes are * active but not yet reflected by objects in the scope chain. If a block * scope contains a with, eval, XML filtering predicate, or similar such * dynamically scoped construct, then compile-time block scope at fp->blocks * must reflect at runtime. */ extern JSObject * js_GetScopeChain(JSContext *cx, JSStackFrame *fp); /* * Given a context and a vector of [callee, this, args...] for a function that * was specified with a JSFUN_THISP_PRIMITIVE flag, get the primitive value of * |this| into *thisvp. In doing so, if |this| is an object, insist it is an * instance of clasp and extract its private slot value to return via *thisvp. * * NB: this function loads and uses *vp before storing *thisvp, so the two may * alias the same jsval. */ extern JSBool js_GetPrimitiveThis(JSContext *cx, jsval *vp, JSClass *clasp, jsval *thisvp); /* * For a call with arguments argv including argv[-1] (nominal |this|) and * argv[-2] (callee) replace null |this| with callee's parent, replace * primitive values with the equivalent wrapper objects and censor activation * objects as, per ECMA-262, they may not be referred to by |this|. argv[-1] * must not be a JSVAL_VOID. */ extern JSObject * js_ComputeThis(JSContext *cx, JSBool lazy, jsval *argv); extern const uint16 js_PrimitiveTestFlags[]; #define PRIMITIVE_THIS_TEST(fun,thisv) \ (JS_ASSERT(!JSVAL_IS_VOID(thisv)), \ JSFUN_THISP_TEST(JSFUN_THISP_FLAGS((fun)->flags), \ js_PrimitiveTestFlags[JSVAL_TAG(thisv) - 1])) /* * NB: js_Invoke requires that cx is currently running JS (i.e., that cx->fp * is non-null), and that vp points to the callee, |this| parameter, and * actual arguments of the call. [vp .. vp + 2 + argc) must belong to the last * JS stack segment that js_AllocStack allocated. The function may use the * space available after vp + 2 + argc in the stack segment for temporaries, * so the caller should not use that space for values that must be preserved * across the call. */ extern JS_FRIEND_API(JSBool) js_Invoke(JSContext *cx, uintN argc, jsval *vp, uintN flags); /* * Consolidated js_Invoke flags simply rename certain JSFRAME_* flags, so that * we can share bits stored in JSStackFrame.flags and passed to: * * js_Invoke * js_InternalInvoke * js_ValueToFunction * js_ValueToFunctionObject * js_ValueToCallableObject * js_ReportIsNotFunction * * See jsfun.h for the latter four and flag renaming macros. */ #define JSINVOKE_CONSTRUCT JSFRAME_CONSTRUCTING #define JSINVOKE_ITERATOR JSFRAME_ITERATOR /* * Mask to isolate construct and iterator flags for use with jsfun.h functions. */ #define JSINVOKE_FUNFLAGS (JSINVOKE_CONSTRUCT | JSINVOKE_ITERATOR) /* * "Internal" calls may come from C or C++ code using a JSContext on which no * JS is running (!cx->fp), so they may need to push a dummy JSStackFrame. */ #define js_InternalCall(cx,obj,fval,argc,argv,rval) \ js_InternalInvoke(cx, obj, fval, 0, argc, argv, rval) #define js_InternalConstruct(cx,obj,fval,argc,argv,rval) \ js_InternalInvoke(cx, obj, fval, JSINVOKE_CONSTRUCT, argc, argv, rval) extern JSBool js_InternalInvoke(JSContext *cx, JSObject *obj, jsval fval, uintN flags, uintN argc, jsval *argv, jsval *rval); extern JSBool js_InternalGetOrSet(JSContext *cx, JSObject *obj, jsid id, jsval fval, JSAccessMode mode, uintN argc, jsval *argv, jsval *rval); extern JSBool js_Execute(JSContext *cx, JSObject *chain, JSScript *script, JSStackFrame *down, uintN flags, jsval *result); extern JSBool js_InvokeConstructor(JSContext *cx, uintN argc, JSBool clampReturn, jsval *vp); extern JSBool js_Interpret(JSContext *cx); #define JSPROP_INITIALIZER 0x100 /* NB: Not a valid property attribute. */ extern JSBool js_CheckRedeclaration(JSContext *cx, JSObject *obj, jsid id, uintN attrs, JSObject **objp, JSProperty **propp); extern JSBool js_StrictlyEqual(JSContext *cx, jsval lval, jsval rval); /* * JS_LONE_INTERPRET indicates that the compiler should see just the code for * the js_Interpret function when compiling jsinterp.cpp. The rest of the code * from the file should be visible only when compiling jsinvoke.cpp. It allows * platform builds to optimize selectively js_Interpret when the granularity * of the optimizations with the given compiler is a compilation unit. * * JS_STATIC_INTERPRET is the modifier for functions defined in jsinterp.cpp * that only js_Interpret calls. When JS_LONE_INTERPRET is true all such * functions are declared below. */ #ifndef JS_LONE_INTERPRET # ifdef _MSC_VER # define JS_LONE_INTERPRET 0 # else # define JS_LONE_INTERPRET 1 # endif #endif #if !JS_LONE_INTERPRET # define JS_STATIC_INTERPRET static #else # define JS_STATIC_INTERPRET extern jsval * js_AllocRawStack(JSContext *cx, uintN nslots, void **markp); extern void js_FreeRawStack(JSContext *cx, void *mark); /* * ECMA requires "the global object", but in embeddings such as the browser, * which have multiple top-level objects (windows, frames, etc. in the DOM), * we prefer fun's parent. An example that causes this code to run: * * // in window w1 * function f() { return this } * function g() { return f } * * // in window w2 * var h = w1.g() * alert(h() == w1) * * The alert should display "true". */ extern JSObject * js_ComputeGlobalThis(JSContext *cx, JSBool lazy, jsval *argv); extern JSBool js_EnterWith(JSContext *cx, jsint stackIndex); extern void js_LeaveWith(JSContext *cx); extern JSClass * js_IsActiveWithOrBlock(JSContext *cx, JSObject *obj, int stackDepth); extern jsint js_CountWithBlocks(JSContext *cx, JSStackFrame *fp); /* * Unwind block and scope chains to match the given depth. The function sets * fp->sp on return to stackDepth. */ extern JSBool js_UnwindScope(JSContext *cx, JSStackFrame *fp, jsint stackDepth, JSBool normalUnwind); extern JSBool js_InternNonIntElementId(JSContext *cx, JSObject *obj, jsval idval, jsid *idp); extern JSBool js_OnUnknownMethod(JSContext *cx, jsval *vp); /* * Find the results of incrementing or decrementing *vp. For pre-increments, * both *vp and *vp2 will contain the result on return. For post-increments, * vp will contain the original value converted to a number and vp2 will get * the result. Both vp and vp2 must be roots. */ extern JSBool js_DoIncDec(JSContext *cx, const JSCodeSpec *cs, jsval *vp, jsval *vp2); /* * Opcode tracing helper. When len is not 0, cx->fp->regs->pc[-len] gives the * previous opcode. */ extern void js_TraceOpcode(JSContext *cx, jsint len); /* * JS_OPMETER helper functions. */ extern void js_MeterOpcodePair(JSOp op1, JSOp op2); extern void js_MeterSlotOpcode(JSOp op, uint32 slot); #endif /* JS_LONE_INTERPRET */ JS_END_EXTERN_C #endif /* jsinterp_h___ */