trunk/js/jsgc.h

/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
 *
 * ***** 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 jsgc_h___
#define jsgc_h___
/*
 * JS Garbage Collector.
 */
#include "jsprvtd.h"
#include "jspubtd.h"
#include "jsdhash.h"
#include "jsbit.h"
#include "jsutil.h"
#include "jstask.h"

JS_BEGIN_EXTERN_C

#define JSTRACE_XML         3

/*
 * One past the maximum trace kind.
 */
#define JSTRACE_LIMIT       4

/*
 * We use the trace kinds as the types for all GC things except external
 * strings.
 */
#define GCX_OBJECT              JSTRACE_OBJECT      /* JSObject */
#define GCX_DOUBLE              JSTRACE_DOUBLE      /* jsdouble */
#define GCX_STRING              JSTRACE_STRING      /* JSString */
#define GCX_XML                 JSTRACE_XML         /* JSXML */
#define GCX_EXTERNAL_STRING     JSTRACE_LIMIT       /* JSString with external
                                                       chars */
/*
 * The number of defined GC types and the maximum limit for the number of
 * possible GC types.
 */
#define GCX_NTYPES              (GCX_EXTERNAL_STRING + 8)
#define GCX_LIMIT_LOG2         4           /* type index bits */
#define GCX_LIMIT              JS_BIT(GCX_LIMIT_LOG2)

/* GC flag definitions, must fit in 8 bits (type index goes in the low bits). */
#define GCF_TYPEMASK    JS_BITMASK(GCX_LIMIT_LOG2)
#define GCF_MARK        JS_BIT(GCX_LIMIT_LOG2)
#define GCF_FINAL       JS_BIT(GCX_LIMIT_LOG2 + 1)
#define GCF_LOCKSHIFT   (GCX_LIMIT_LOG2 + 2)   /* lock bit shift */
#define GCF_LOCK        JS_BIT(GCF_LOCKSHIFT)   /* lock request bit in API */

/*
 * Get the type of the external string or -1 if the string was not created
 * with JS_NewExternalString.
 */
extern intN
js_GetExternalStringGCType(JSString *str);

extern JS_FRIEND_API(uint32)
js_GetGCThingTraceKind(void *thing);

/*
 * The sole purpose of the function is to preserve public API compatibility
 * in JS_GetStringBytes which takes only single JSString* argument.
 */
JSRuntime*
js_GetGCStringRuntime(JSString *str);

#if 1
/*
 * Since we're forcing a GC from JS_GC anyway, don't bother wasting cycles
 * loading oldval.  XXX remove implied force, fix jsinterp.c's "second arg
 * ignored", etc.
 */
#define GC_POKE(cx, oldval) ((cx)->runtime->gcPoke = JS_TRUE)
#else
#define GC_POKE(cx, oldval) ((cx)->runtime->gcPoke = JSVAL_IS_GCTHING(oldval))
#endif

extern JSBool
js_InitGC(JSRuntime *rt, uint32 maxbytes);

extern void
js_FinishGC(JSRuntime *rt);

extern intN
js_ChangeExternalStringFinalizer(JSStringFinalizeOp oldop,
                                 JSStringFinalizeOp newop);

extern JSBool
js_AddRoot(JSContext *cx, void *rp, const char *name);

extern JSBool
js_AddRootRT(JSRuntime *rt, void *rp, const char *name);

extern JSBool
js_RemoveRoot(JSRuntime *rt, void *rp);

#ifdef DEBUG
extern void
js_DumpNamedRoots(JSRuntime *rt,
                  void (*dump)(const char *name, void *rp, void *data),
                  void *data);
#endif

extern uint32
js_MapGCRoots(JSRuntime *rt, JSGCRootMapFun map, void *data);

/* Table of pointers with count valid members. */
typedef struct JSPtrTable {
    size_t      count;
    void        **array;
} JSPtrTable;

extern JSBool
js_RegisterCloseableIterator(JSContext *cx, JSObject *obj);

/*
 * The private JSGCThing struct, which describes a gcFreeList element.
 */
struct JSGCThing {
    JSGCThing   *next;
    uint8       *flagp;
};

#define GC_NBYTES_MAX           (10 * sizeof(JSGCThing))
#define GC_NUM_FREELISTS        (GC_NBYTES_MAX / sizeof(JSGCThing))
#define GC_FREELIST_NBYTES(i)   (((i) + 1) * sizeof(JSGCThing))
#define GC_FREELIST_INDEX(n)    (((n) / sizeof(JSGCThing)) - 1)

/*
 * Allocates a new GC thing of the given size. After a successful allocation
 * the caller must fully initialize the thing before calling any function that
 * can potentially trigger GC. This will ensure that GC tracing never sees junk
 * values stored in the partially initialized thing.
 */
extern JSObject*
js_NewGCObject(JSContext *cx, uintN flags);

extern JSString*
js_NewGCString(JSContext *cx, uintN flags);

extern JSFunction*
js_NewGCFunction(JSContext *cx, uintN flags);

extern JSXML*
js_NewGCXML(JSContext *cx, uintN flags);

/*
 * Allocate a new double jsval and store the result in *vp. vp must be a root.
 * The function does not copy the result into any weak root.
 */
extern JSBool
js_NewDoubleInRootedValue(JSContext *cx, jsdouble d, jsval *vp);

/*
 * Return a pointer to a new GC-allocated and weakly-rooted jsdouble number,
 * or null when the allocation fails.
 */
extern jsdouble *
js_NewWeaklyRootedDouble(JSContext *cx, jsdouble d);

#ifdef JS_TRACER
extern JSBool
js_ReserveObjects(JSContext *cx, size_t nobjects);
#endif

extern JSBool
js_LockGCThingRT(JSRuntime *rt, void *thing);

extern JSBool
js_UnlockGCThingRT(JSRuntime *rt, void *thing);

extern JSBool
js_IsAboutToBeFinalized(JSContext *cx, void *thing);

/*
 * Macro to test if a traversal is the marking phase of GC to avoid exposing
 * ScriptFilenameEntry to traversal implementations.
 */
#define IS_GC_MARKING_TRACER(trc) ((trc)->callback == NULL)

#if JS_HAS_XML_SUPPORT
# define JS_IS_VALID_TRACE_KIND(kind) ((uint32)(kind) < JSTRACE_LIMIT)
#else
# define JS_IS_VALID_TRACE_KIND(kind) ((uint32)(kind) <= JSTRACE_STRING)
#endif

/*
 * Trace jsval when JSVAL_IS_OBJECT(v) can be a GC thing pointer tagged as a
 * jsval. NB: punning an arbitrary JSString * as an untagged (object-tagged)
 * jsval no longer works due to static int and unit strings!
 */
extern void
js_CallValueTracerIfGCThing(JSTracer *trc, jsval v);

extern void
js_TraceStackFrame(JSTracer *trc, JSStackFrame *fp);

extern JS_REQUIRES_STACK void
js_TraceRuntime(JSTracer *trc, JSBool allAtoms);

extern JS_REQUIRES_STACK JS_FRIEND_API(void)
js_TraceContext(JSTracer *trc, JSContext *acx);

/*
 * Schedule the GC call at a later safe point.
 */
#ifndef JS_THREADSAFE
# define js_TriggerGC(cx, gcLocked)    js_TriggerGC (cx)
#endif

extern void
js_TriggerGC(JSContext *cx, JSBool gcLocked);

/*
 * Kinds of js_GC invocation.
 */
typedef enum JSGCInvocationKind {
    /* Normal invocation. */
    GC_NORMAL           = 0,

    /*
     * Called from js_DestroyContext for last JSContext in a JSRuntime, when
     * it is imperative that rt->gcPoke gets cleared early in js_GC.
     */
    GC_LAST_CONTEXT     = 1,

    /*
     * Flag bit telling js_GC that the caller has already acquired rt->gcLock.
     * Currently, this flag is set for the invocation kinds that also preserve
     * atoms and weak roots, so we don't need another bit for GC_KEEP_ATOMS.
     */
    GC_LOCK_HELD        = 0x10,
    GC_KEEP_ATOMS       = GC_LOCK_HELD,

    /*
     * Called from js_SetProtoOrParent with a request to set an object's proto
     * or parent slot inserted on rt->setSlotRequests.
     */
    GC_SET_SLOT_REQUEST = GC_LOCK_HELD | 1,

    /*
     * Called from js_NewGCThing as a last-ditch GC attempt. See comments in
     * jsgc.c just before js_GC's definition for details.
     */
    GC_LAST_DITCH       = GC_LOCK_HELD | 2
} JSGCInvocationKind;

extern void
js_GC(JSContext *cx, JSGCInvocationKind gckind);

typedef struct JSGCArenaInfo JSGCArenaInfo;
typedef struct JSGCArenaList JSGCArenaList;
typedef struct JSGCChunkInfo JSGCChunkInfo;

struct JSGCArenaList {
    JSGCArenaInfo   *last;          /* last allocated GC arena */
    uint32          lastCount;      /* number of allocated things in the last
                                       arena */
    uint32          thingSize;      /* size of things to allocate on this list
                                     */
    JSGCThing       *freeList;      /* list of free GC things */
};

typedef union JSGCDoubleCell JSGCDoubleCell;

union JSGCDoubleCell {
    double          number;
    JSGCDoubleCell  *link;
};

typedef struct JSGCDoubleArenaList {
    JSGCArenaInfo   *first;             /* first allocated GC arena */
    jsbitmap        *nextDoubleFlags;   /* bitmask with flags to check for free
                                           things */
} JSGCDoubleArenaList;

extern void
js_DestroyScriptsToGC(JSContext *cx, JSThreadData *data);

struct JSWeakRoots {
    /* Most recently created things by type, members of the GC's root set. */
    void            *newborn[GCX_NTYPES];

    /* Atom root for the last-looked-up atom on this context. */
    jsval           lastAtom;

    /* Root for the result of the most recent js_InternalInvoke call. */
    jsval           lastInternalResult;
};

#define JS_CLEAR_WEAK_ROOTS(wr) (memset((wr), 0, sizeof(JSWeakRoots)))

#ifdef __cplusplus /* Allow inclusion from LiveConnect C files. */
#ifdef JS_THREADSAFE
class JSFreePointerListTask : public JSBackgroundTask {
    void *head;
  public:
    JSFreePointerListTask() : head(NULL) {}

    void add(void* ptr) {
        *(void**)ptr = head;
        head = ptr;
    }

    void run() {
        void *ptr = head;
        while (ptr) {
            void *next = *(void **)ptr;
            js_free(ptr);
            ptr = next;
        }
    }
};
#endif
#endif /* __cplusplus */

/*
 * Free the chars held by str when it is finalized by the GC. When type is
 * less then zero, it denotes an internal string. Otherwise it denotes the
 * type of the external string allocated with JS_NewExternalString.
 *
 * This function always needs rt but can live with null cx.
 */
extern void
js_FinalizeStringRT(JSRuntime *rt, JSString *str, intN type, JSContext *cx);

#ifdef DEBUG_notme
#define JS_GCMETER 1
#endif

#ifdef JS_GCMETER

typedef struct JSGCArenaStats {
    uint32  alloc;          /* allocation attempts */
    uint32  localalloc;     /* allocations from local lists */
    uint32  retry;          /* allocation retries after running the GC */
    uint32  fail;           /* allocation failures */
    uint32  nthings;        /* live GC things */
    uint32  maxthings;      /* maximum of live GC cells */
    double  totalthings;    /* live GC things the GC scanned so far */
    uint32  narenas;        /* number of arena in list before the GC */
    uint32  newarenas;      /* new arenas allocated before the last GC */
    uint32  livearenas;     /* number of live arenas after the last GC */
    uint32  maxarenas;      /* maximum of allocated arenas */
    uint32  totalarenas;    /* total number of arenas with live things that
                               GC scanned so far */
} JSGCArenaStats;

typedef struct JSGCStats {
    uint32  finalfail;  /* finalizer calls allocator failures */
    uint32  lockborn;   /* things born locked */
    uint32  lock;       /* valid lock calls */
    uint32  unlock;     /* valid unlock calls */
    uint32  depth;      /* mark tail recursion depth */
    uint32  maxdepth;   /* maximum mark tail recursion depth */
    uint32  cdepth;     /* mark recursion depth of C functions */
    uint32  maxcdepth;  /* maximum mark recursion depth of C functions */
    uint32  untraced;   /* number of times tracing of GC thing's children were
                           delayed due to a low C stack */
#ifdef DEBUG
    uint32  maxuntraced;/* maximum number of things with children to trace
                           later */
#endif
    uint32  maxlevel;   /* maximum GC nesting (indirect recursion) level */
    uint32  poke;       /* number of potentially useful GC calls */
    uint32  afree;      /* thing arenas freed so far */
    uint32  stackseg;   /* total extraordinary stack segments scanned */
    uint32  segslots;   /* total stack segment jsval slots scanned */
    uint32  nclose;     /* number of objects with close hooks */
    uint32  maxnclose;  /* max number of objects with close hooks */
    uint32  closelater; /* number of close hooks scheduled to run */
    uint32  maxcloselater; /* max number of close hooks scheduled to run */

    JSGCArenaStats  arenaStats[GC_NUM_FREELISTS];
    JSGCArenaStats  doubleArenaStats;
} JSGCStats;

extern JS_FRIEND_API(void)
js_DumpGCStats(JSRuntime *rt, FILE *fp);

#endif /* JS_GCMETER */

JS_END_EXTERN_C

#endif /* jsgc_h___ */
1	siliconforks	332	/* -- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 --
2			*
3			* *** BEGIN LICENSE BLOCK ***
4			* Version: MPL 1.1/GPL 2.0/LGPL 2.1
5			*
6			* The contents of this file are subject to the Mozilla Public License Version
7			* 1.1 (the "License"); you may not use this file except in compliance with
8			* the License. You may obtain a copy of the License at
9			* http://www.mozilla.org/MPL/
10			*
11			* Software distributed under the License is distributed on an "AS IS" basis,
12			* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
13			* for the specific language governing rights and limitations under the
14			* License.
15			*
16			* The Original Code is Mozilla Communicator client code, released
17			* March 31, 1998.
18			*
19			* The Initial Developer of the Original Code is
20			* Netscape Communications Corporation.
21			* Portions created by the Initial Developer are Copyright (C) 1998
22			* the Initial Developer. All Rights Reserved.
23			*
24			* Contributor(s):
25			*
26			* Alternatively, the contents of this file may be used under the terms of
27			* either of the GNU General Public License Version 2 or later (the "GPL"),
28			* or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
29			* in which case the provisions of the GPL or the LGPL are applicable instead
30			* of those above. If you wish to allow use of your version of this file only
31			* under the terms of either the GPL or the LGPL, and not to allow others to
32			* use your version of this file under the terms of the MPL, indicate your
33			* decision by deleting the provisions above and replace them with the notice
34			* and other provisions required by the GPL or the LGPL. If you do not delete
35			* the provisions above, a recipient may use your version of this file under
36			* the terms of any one of the MPL, the GPL or the LGPL.
37			*
38			* *** END LICENSE BLOCK *** */
39
40			#ifndef jsgc_h___
41			#define jsgc_h___
42			/*
43			* JS Garbage Collector.
44			*/
45			#include "jsprvtd.h"
46			#include "jspubtd.h"
47			#include "jsdhash.h"
48			#include "jsbit.h"
49			#include "jsutil.h"
50	siliconforks	507	#include "jstask.h"
51	siliconforks	332
52			JS_BEGIN_EXTERN_C
53
54			#define JSTRACE_XML 3
55
56			/*
57			* One past the maximum trace kind.
58			*/
59			#define JSTRACE_LIMIT 4
60
61			/*
62			* We use the trace kinds as the types for all GC things except external
63			* strings.
64			*/
65			#define GCX_OBJECT JSTRACE_OBJECT /* JSObject */
66			#define GCX_DOUBLE JSTRACE_DOUBLE /* jsdouble */
67			#define GCX_STRING JSTRACE_STRING /* JSString */
68			#define GCX_XML JSTRACE_XML /* JSXML */
69			#define GCX_EXTERNAL_STRING JSTRACE_LIMIT /* JSString with external
70			chars */
71			/*
72	siliconforks	460	* The number of defined GC types and the maximum limit for the number of
73			* possible GC types.
74	siliconforks	332	*/
75			#define GCX_NTYPES (GCX_EXTERNAL_STRING + 8)
76			#define GCX_LIMIT_LOG2 4 /* type index bits */
77			#define GCX_LIMIT JS_BIT(GCX_LIMIT_LOG2)
78
79			/* GC flag definitions, must fit in 8 bits (type index goes in the low bits). */
80			#define GCF_TYPEMASK JS_BITMASK(GCX_LIMIT_LOG2)
81			#define GCF_MARK JS_BIT(GCX_LIMIT_LOG2)
82			#define GCF_FINAL JS_BIT(GCX_LIMIT_LOG2 + 1)
83			#define GCF_LOCKSHIFT (GCX_LIMIT_LOG2 + 2) /* lock bit shift */
84			#define GCF_LOCK JS_BIT(GCF_LOCKSHIFT) /* lock request bit in API */
85
86			/*
87			* Get the type of the external string or -1 if the string was not created
88			* with JS_NewExternalString.
89			*/
90			extern intN
91			js_GetExternalStringGCType(JSString *str);
92
93			extern JS_FRIEND_API(uint32)
94			js_GetGCThingTraceKind(void *thing);
95
96			/*
97			* The sole purpose of the function is to preserve public API compatibility
98			* in JS_GetStringBytes which takes only single JSString* argument.
99			*/
100			JSRuntime*
101			js_GetGCStringRuntime(JSString *str);
102
103			#if 1
104			/*
105			* Since we're forcing a GC from JS_GC anyway, don't bother wasting cycles
106			* loading oldval. XXX remove implied force, fix jsinterp.c's "second arg
107			* ignored", etc.
108			*/
109			#define GC_POKE(cx, oldval) ((cx)->runtime->gcPoke = JS_TRUE)
110			#else
111			#define GC_POKE(cx, oldval) ((cx)->runtime->gcPoke = JSVAL_IS_GCTHING(oldval))
112			#endif
113
114			extern JSBool
115			js_InitGC(JSRuntime *rt, uint32 maxbytes);
116
117			extern void
118			js_FinishGC(JSRuntime *rt);
119
120			extern intN
121			js_ChangeExternalStringFinalizer(JSStringFinalizeOp oldop,
122			JSStringFinalizeOp newop);
123
124			extern JSBool
125			js_AddRoot(JSContext cx, void rp, const char *name);
126
127			extern JSBool
128			js_AddRootRT(JSRuntime rt, void rp, const char *name);
129
130			extern JSBool
131			js_RemoveRoot(JSRuntime rt, void rp);
132
133			#ifdef DEBUG
134			extern void
135			js_DumpNamedRoots(JSRuntime *rt,
136			void (dump)(const char name, void rp, void data),
137			void *data);
138			#endif
139
140			extern uint32
141			js_MapGCRoots(JSRuntime rt, JSGCRootMapFun map, void data);
142
143			/* Table of pointers with count valid members. */
144			typedef struct JSPtrTable {
145			size_t count;
146			void **array;
147			} JSPtrTable;
148
149			extern JSBool
150			js_RegisterCloseableIterator(JSContext cx, JSObject obj);
151
152			/*
153			* The private JSGCThing struct, which describes a gcFreeList element.
154			*/
155			struct JSGCThing {
156			JSGCThing *next;
157			uint8 *flagp;
158			};
159
160			#define GC_NBYTES_MAX (10 * sizeof(JSGCThing))
161			#define GC_NUM_FREELISTS (GC_NBYTES_MAX / sizeof(JSGCThing))
162			#define GC_FREELIST_NBYTES(i) (((i) + 1) * sizeof(JSGCThing))
163			#define GC_FREELIST_INDEX(n) (((n) / sizeof(JSGCThing)) - 1)
164
165			/*
166			* Allocates a new GC thing of the given size. After a successful allocation
167			* the caller must fully initialize the thing before calling any function that
168			* can potentially trigger GC. This will ensure that GC tracing never sees junk
169			* values stored in the partially initialized thing.
170			*/
171	siliconforks	507	extern JSObject*
172			js_NewGCObject(JSContext *cx, uintN flags);
173	siliconforks	332
174	siliconforks	507	extern JSString*
175			js_NewGCString(JSContext *cx, uintN flags);
176
177			extern JSFunction*
178			js_NewGCFunction(JSContext *cx, uintN flags);
179
180			extern JSXML*
181			js_NewGCXML(JSContext *cx, uintN flags);
182
183	siliconforks	332	/*
184			* Allocate a new double jsval and store the result in *vp. vp must be a root.
185			* The function does not copy the result into any weak root.
186			*/
187			extern JSBool
188			js_NewDoubleInRootedValue(JSContext cx, jsdouble d, jsval vp);
189
190			/*
191			* Return a pointer to a new GC-allocated and weakly-rooted jsdouble number,
192			* or null when the allocation fails.
193			*/
194			extern jsdouble *
195			js_NewWeaklyRootedDouble(JSContext *cx, jsdouble d);
196
197	siliconforks	460	#ifdef JS_TRACER
198	siliconforks	332	extern JSBool
199	siliconforks	460	js_ReserveObjects(JSContext *cx, size_t nobjects);
200			#endif
201
202			extern JSBool
203	siliconforks	332	js_LockGCThingRT(JSRuntime rt, void thing);
204
205			extern JSBool
206			js_UnlockGCThingRT(JSRuntime rt, void thing);
207
208			extern JSBool
209			js_IsAboutToBeFinalized(JSContext cx, void thing);
210
211			/*
212			* Macro to test if a traversal is the marking phase of GC to avoid exposing
213			* ScriptFilenameEntry to traversal implementations.
214			*/
215			#define IS_GC_MARKING_TRACER(trc) ((trc)->callback == NULL)
216
217			#if JS_HAS_XML_SUPPORT
218			# define JS_IS_VALID_TRACE_KIND(kind) ((uint32)(kind) < JSTRACE_LIMIT)
219			#else
220			# define JS_IS_VALID_TRACE_KIND(kind) ((uint32)(kind) <= JSTRACE_STRING)
221			#endif
222
223			/*
224	siliconforks	507	* Trace jsval when JSVAL_IS_OBJECT(v) can be a GC thing pointer tagged as a
225			* jsval. NB: punning an arbitrary JSString * as an untagged (object-tagged)
226			* jsval no longer works due to static int and unit strings!
227	siliconforks	332	*/
228			extern void
229			js_CallValueTracerIfGCThing(JSTracer *trc, jsval v);
230
231			extern void
232			js_TraceStackFrame(JSTracer trc, JSStackFrame fp);
233
234	siliconforks	460	extern JS_REQUIRES_STACK void
235	siliconforks	332	js_TraceRuntime(JSTracer *trc, JSBool allAtoms);
236
237	siliconforks	460	extern JS_REQUIRES_STACK JS_FRIEND_API(void)
238	siliconforks	332	js_TraceContext(JSTracer trc, JSContext acx);
239
240			/*
241	siliconforks	460	* Schedule the GC call at a later safe point.
242			*/
243			#ifndef JS_THREADSAFE
244			# define js_TriggerGC(cx, gcLocked) js_TriggerGC (cx)
245			#endif
246
247			extern void
248			js_TriggerGC(JSContext *cx, JSBool gcLocked);
249
250			/*
251	siliconforks	332	* Kinds of js_GC invocation.
252			*/
253			typedef enum JSGCInvocationKind {
254			/* Normal invocation. */
255			GC_NORMAL = 0,
256
257			/*
258			* Called from js_DestroyContext for last JSContext in a JSRuntime, when
259			* it is imperative that rt->gcPoke gets cleared early in js_GC.
260			*/
261			GC_LAST_CONTEXT = 1,
262
263			/*
264			* Flag bit telling js_GC that the caller has already acquired rt->gcLock.
265			* Currently, this flag is set for the invocation kinds that also preserve
266			* atoms and weak roots, so we don't need another bit for GC_KEEP_ATOMS.
267			*/
268			GC_LOCK_HELD = 0x10,
269			GC_KEEP_ATOMS = GC_LOCK_HELD,
270
271			/*
272			* Called from js_SetProtoOrParent with a request to set an object's proto
273			* or parent slot inserted on rt->setSlotRequests.
274			*/
275			GC_SET_SLOT_REQUEST = GC_LOCK_HELD \| 1,
276
277			/*
278			* Called from js_NewGCThing as a last-ditch GC attempt. See comments in
279			* jsgc.c just before js_GC's definition for details.
280			*/
281			GC_LAST_DITCH = GC_LOCK_HELD \| 2
282			} JSGCInvocationKind;
283
284			extern void
285			js_GC(JSContext *cx, JSGCInvocationKind gckind);
286
287			typedef struct JSGCArenaInfo JSGCArenaInfo;
288			typedef struct JSGCArenaList JSGCArenaList;
289			typedef struct JSGCChunkInfo JSGCChunkInfo;
290
291			struct JSGCArenaList {
292			JSGCArenaInfo last; / last allocated GC arena */
293	siliconforks	507	uint32 lastCount; /* number of allocated things in the last
294	siliconforks	332	arena */
295	siliconforks	507	uint32 thingSize; /* size of things to allocate on this list
296	siliconforks	332	*/
297			JSGCThing freeList; / list of free GC things */
298			};
299
300			typedef union JSGCDoubleCell JSGCDoubleCell;
301
302			union JSGCDoubleCell {
303			double number;
304			JSGCDoubleCell *link;
305			};
306
307			typedef struct JSGCDoubleArenaList {
308			JSGCArenaInfo first; / first allocated GC arena */
309			jsbitmap nextDoubleFlags; / bitmask with flags to check for free
310			things */
311			} JSGCDoubleArenaList;
312
313			extern void
314	siliconforks	460	js_DestroyScriptsToGC(JSContext cx, JSThreadData data);
315
316	siliconforks	332	struct JSWeakRoots {
317			/* Most recently created things by type, members of the GC's root set. */
318			void *newborn[GCX_NTYPES];
319
320			/* Atom root for the last-looked-up atom on this context. */
321			jsval lastAtom;
322
323			/* Root for the result of the most recent js_InternalInvoke call. */
324			jsval lastInternalResult;
325			};
326
327			#define JS_CLEAR_WEAK_ROOTS(wr) (memset((wr), 0, sizeof(JSWeakRoots)))
328
329	siliconforks	507	#ifdef __cplusplus /* Allow inclusion from LiveConnect C files. */
330			#ifdef JS_THREADSAFE
331			class JSFreePointerListTask : public JSBackgroundTask {
332			void *head;
333			public:
334			JSFreePointerListTask() : head(NULL) {}
335
336			void add(void* ptr) {
337			(void*)ptr = head;
338			head = ptr;
339			}
340
341			void run() {
342			void *ptr = head;
343			while (ptr) {
344			void next = (void **)ptr;
345			js_free(ptr);
346			ptr = next;
347			}
348			}
349			};
350			#endif
351			#endif /* __cplusplus */
352
353	siliconforks	332	/*
354	siliconforks	507	* Free the chars held by str when it is finalized by the GC. When type is
355			* less then zero, it denotes an internal string. Otherwise it denotes the
356			* type of the external string allocated with JS_NewExternalString.
357	siliconforks	332	*
358	siliconforks	507	* This function always needs rt but can live with null cx.
359	siliconforks	332	*/
360			extern void
361	siliconforks	507	js_FinalizeStringRT(JSRuntime rt, JSString str, intN type, JSContext *cx);
362	siliconforks	332
363			#ifdef DEBUG_notme
364			#define JS_GCMETER 1
365			#endif
366
367			#ifdef JS_GCMETER
368
369			typedef struct JSGCArenaStats {
370			uint32 alloc; /* allocation attempts */
371			uint32 localalloc; /* allocations from local lists */
372			uint32 retry; /* allocation retries after running the GC */
373			uint32 fail; /* allocation failures */
374			uint32 nthings; /* live GC things */
375			uint32 maxthings; /* maximum of live GC cells */
376			double totalthings; /* live GC things the GC scanned so far */
377			uint32 narenas; /* number of arena in list before the GC */
378			uint32 newarenas; /* new arenas allocated before the last GC */
379			uint32 livearenas; /* number of live arenas after the last GC */
380			uint32 maxarenas; /* maximum of allocated arenas */
381			uint32 totalarenas; /* total number of arenas with live things that
382			GC scanned so far */
383			} JSGCArenaStats;
384
385			typedef struct JSGCStats {
386			uint32 finalfail; /* finalizer calls allocator failures */
387			uint32 lockborn; /* things born locked */
388			uint32 lock; /* valid lock calls */
389			uint32 unlock; /* valid unlock calls */
390			uint32 depth; /* mark tail recursion depth */
391			uint32 maxdepth; /* maximum mark tail recursion depth */
392			uint32 cdepth; /* mark recursion depth of C functions */
393			uint32 maxcdepth; /* maximum mark recursion depth of C functions */
394			uint32 untraced; /* number of times tracing of GC thing's children were
395			delayed due to a low C stack */
396			#ifdef DEBUG
397			uint32 maxuntraced;/* maximum number of things with children to trace
398			later */
399			#endif
400			uint32 maxlevel; /* maximum GC nesting (indirect recursion) level */
401			uint32 poke; /* number of potentially useful GC calls */
402			uint32 afree; /* thing arenas freed so far */
403			uint32 stackseg; /* total extraordinary stack segments scanned */
404			uint32 segslots; /* total stack segment jsval slots scanned */
405			uint32 nclose; /* number of objects with close hooks */
406			uint32 maxnclose; /* max number of objects with close hooks */
407			uint32 closelater; /* number of close hooks scheduled to run */
408			uint32 maxcloselater; /* max number of close hooks scheduled to run */
409
410			JSGCArenaStats arenaStats[GC_NUM_FREELISTS];
411			JSGCArenaStats doubleArenaStats;
412			} JSGCStats;
413
414			extern JS_FRIEND_API(void)
415			js_DumpGCStats(JSRuntime rt, FILE fp);
416
417			#endif /* JS_GCMETER */
418
419			JS_END_EXTERN_C
420
421			#endif /* jsgc_h___ */