/* -*- 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"
JS_BEGIN_EXTERN_C
/* GC thing type indexes. */
#define GCX_OBJECT 0 /* JSObject */
#define GCX_STRING 1 /* JSString */
#define GCX_DOUBLE 2 /* jsdouble */
#define GCX_MUTABLE_STRING 3 /* JSString that's mutable --
single-threaded only! */
#define GCX_PRIVATE 4 /* private (unscanned) data */
#define GCX_NAMESPACE 5 /* JSXMLNamespace */
#define GCX_QNAME 6 /* JSXMLQName */
#define GCX_XML 7 /* JSXML */
#define GCX_EXTERNAL_STRING 8 /* JSString w/ external chars */
#define GCX_NTYPES_LOG2 4 /* type index bits */
#define GCX_NTYPES JS_BIT(GCX_NTYPES_LOG2)
/* GC flag definitions, must fit in 8 bits (type index goes in the low bits). */
#define GCF_TYPEMASK JS_BITMASK(GCX_NTYPES_LOG2)
#define GCF_MARK JS_BIT(GCX_NTYPES_LOG2)
#define GCF_FINAL JS_BIT(GCX_NTYPES_LOG2 + 1)
#define GCF_SYSTEM JS_BIT(GCX_NTYPES_LOG2 + 2)
#define GCF_LOCKSHIFT (GCX_NTYPES_LOG2 + 3) /* lock bit shift */
#define GCF_LOCK JS_BIT(GCF_LOCKSHIFT) /* lock request bit in API */
/* Pseudo-flag that modifies GCX_STRING to make GCX_MUTABLE_STRING. */
#define GCF_MUTABLE 2
#if (GCX_STRING | GCF_MUTABLE) != GCX_MUTABLE_STRING
# error "mutable string type index botch!"
#endif
extern uint8 *
js_GetGCThingFlags(void *thing);
/* These are compatible with JSDHashEntryStub. */
struct JSGCRootHashEntry {
JSDHashEntryHdr hdr;
void *root;
const char *name;
};
struct JSGCLockHashEntry {
JSDHashEntryHdr hdr;
const JSGCThing *thing;
uint32 count;
};
#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 intN
js_ChangeExternalStringFinalizer(JSStringFinalizeOp oldop,
JSStringFinalizeOp newop);
extern JSBool
js_InitGC(JSRuntime *rt, uint32 maxbytes);
extern void
js_FinishGC(JSRuntime *rt);
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);
/*
* 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)
extern void *
js_NewGCThing(JSContext *cx, uintN flags, size_t nbytes);
extern JSBool
js_LockGCThing(JSContext *cx, void *thing);
extern JSBool
js_LockGCThingRT(JSRuntime *rt, void *thing);
extern JSBool
js_UnlockGCThingRT(JSRuntime *rt, void *thing);
extern JSBool
js_IsAboutToBeFinalized(JSContext *cx, void *thing);
extern void
js_MarkAtom(JSContext *cx, JSAtom *atom, void *arg);
/* We avoid a large number of unnecessary calls by doing the flag check first */
#define GC_MARK_ATOM(cx, atom, arg) \
JS_BEGIN_MACRO \
if (!((atom)->flags & ATOM_MARK)) \
js_MarkAtom(cx, atom, arg); \
JS_END_MACRO
extern void
js_MarkGCThing(JSContext *cx, void *thing, void *arg);
#ifdef GC_MARK_DEBUG
typedef struct GCMarkNode GCMarkNode;
struct GCMarkNode {
void *thing;
const char *name;
GCMarkNode *next;
GCMarkNode *prev;
};
#define GC_MARK(cx_, thing_, name_, prev_) \
JS_BEGIN_MACRO \
GCMarkNode node_; \
node_.thing = thing_; \
node_.name = name_; \
node_.next = NULL; \
node_.prev = prev_; \
if (prev_) ((GCMarkNode *)(prev_))->next = &node_; \
js_MarkGCThing(cx_, thing_, &node_); \
JS_END_MACRO
#else /* !GC_MARK_DEBUG */
#define GC_MARK(cx, thing, name, prev) js_MarkGCThing(cx, thing, NULL)
#endif /* !GC_MARK_DEBUG */
/*
* Flags to modify how a GC marks and sweeps:
* GC_KEEP_ATOMS Don't sweep unmarked atoms, they may be in use by the
* compiler, or by an API function that calls js_Atomize,
* when the GC is called from js_NewGCThing, due to a
* malloc failure or the runtime GC-thing limit.
* GC_LAST_CONTEXT Called from js_DestroyContext for last JSContext in a
* JSRuntime, when it is imperative that rt->gcPoke gets
* cleared early in js_GC, if it is set.
* GC_ALREADY_LOCKED rt->gcLock is already held on entry to js_GC, and kept
* on return to its caller.
*/
#define GC_KEEP_ATOMS 0x1
#define GC_LAST_CONTEXT 0x2
#define GC_ALREADY_LOCKED 0x4
extern void
js_ForceGC(JSContext *cx, uintN gcflags);
extern void
js_GC(JSContext *cx, uintN gcflags);
#ifdef DEBUG_notme
#define JS_GCMETER 1
#endif
#ifdef JS_GCMETER
typedef struct JSGCStats {
uint32 alloc; /* number of allocation attempts */
uint32 freelen[GC_NUM_FREELISTS];
/* gcFreeList lengths */
uint32 recycle[GC_NUM_FREELISTS];
/* number of things recycled through gcFreeList */
uint32 retry; /* allocation attempt retries after running the GC */
uint32 retryhalt; /* allocation retries halted by the branch callback */
uint32 fail; /* allocation failures */
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 dswmark; /* mark C stack overflows => Deutsch-Schorr-Waite */
uint32 dswdepth; /* DSW mark depth */
uint32 maxdswdepth;/* maximum DSW mark depth */
uint32 dswup; /* DSW moves up the mark spanning tree */
uint32 dswupstep; /* steps in obj->slots to find DSW-reversed pointer */
uint32 maxlevel; /* maximum GC nesting (indirect recursion) level */
uint32 poke; /* number of potentially useful GC calls */
uint32 nopoke; /* useless GC calls where js_PokeGC was not set */
uint32 afree; /* thing arenas freed so far */
uint32 stackseg; /* total extraordinary stack segments scanned */
uint32 segslots; /* total stack segment jsval slots scanned */
} JSGCStats;
extern JS_FRIEND_API(void)
js_DumpGCStats(JSRuntime *rt, FILE *fp);
#endif /* JS_GCMETER */
#ifdef DEBUG_notme
#define TOO_MUCH_GC 1
#endif
#ifdef WAY_TOO_MUCH_GC
#define TOO_MUCH_GC 1
#endif
JS_END_EXTERN_C
#endif /* jsgc_h___ */