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gecko/js/src/jscntxt.h
Andreas Gal 7c91c2898c Fix warnings (no bug, r=mrbkap).
2010-06-25 17:57:53 -05:00

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/* -*- 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 jscntxt_h___
#define jscntxt_h___
/*
* JS execution context.
*/
#include <string.h>
/* Gross special case for Gecko, which defines malloc/calloc/free. */
#ifdef mozilla_mozalloc_macro_wrappers_h
# define JS_UNDEFD_MOZALLOC_WRAPPERS
/* The "anti-header" */
# include "mozilla/mozalloc_undef_macro_wrappers.h"
#endif
#include "jsarena.h" /* Added by JSIFY */
#include "jsclist.h"
#include "jslong.h"
#include "jsatom.h"
#include "jsdhash.h"
#include "jsdtoa.h"
#include "jsgc.h"
#include "jsgcchunk.h"
#include "jshashtable.h"
#include "jsinterp.h"
#include "jsobj.h"
#include "jspropertycache.h"
#include "jspropertytree.h"
#include "jsprvtd.h"
#include "jspubtd.h"
#include "jsregexp.h"
#include "jsutil.h"
#include "jsarray.h"
#include "jstask.h"
#include "jsvector.h"
#include "prmjtime.h"
#ifdef _MSC_VER
#pragma warning(push)
#pragma warning(disable:4100) /* Silence unreferenced formal parameter warnings */
#pragma warning(push)
#pragma warning(disable:4355) /* Silence warning about "this" used in base member initializer list */
#endif
/*
* js_GetSrcNote cache to avoid O(n^2) growth in finding a source note for a
* given pc in a script. We use the script->code pointer to tag the cache,
* instead of the script address itself, so that source notes are always found
* by offset from the bytecode with which they were generated.
*/
typedef struct JSGSNCache {
jsbytecode *code;
JSDHashTable table;
#ifdef JS_GSNMETER
uint32 hits;
uint32 misses;
uint32 fills;
uint32 purges;
# define GSN_CACHE_METER(cache,cnt) (++(cache)->cnt)
#else
# define GSN_CACHE_METER(cache,cnt) /* nothing */
#endif
} JSGSNCache;
#define js_FinishGSNCache(cache) js_PurgeGSNCache(cache)
extern void
js_PurgeGSNCache(JSGSNCache *cache);
/* These helper macros take a cx as parameter and operate on its GSN cache. */
#define JS_PURGE_GSN_CACHE(cx) js_PurgeGSNCache(&JS_GSN_CACHE(cx))
#define JS_METER_GSN_CACHE(cx,cnt) GSN_CACHE_METER(&JS_GSN_CACHE(cx), cnt)
/* Forward declarations of nanojit types. */
namespace nanojit {
class Assembler;
class CodeAlloc;
class Fragment;
template<typename K> struct DefaultHash;
template<typename K, typename V, typename H> class HashMap;
template<typename T> class Seq;
} /* namespace nanojit */
namespace js {
/* Tracer constants. */
static const size_t MONITOR_N_GLOBAL_STATES = 4;
static const size_t FRAGMENT_TABLE_SIZE = 512;
static const size_t MAX_NATIVE_STACK_SLOTS = 4096;
static const size_t MAX_CALL_STACK_ENTRIES = 500;
static const size_t MAX_GLOBAL_SLOTS = 4096;
static const size_t GLOBAL_SLOTS_BUFFER_SIZE = MAX_GLOBAL_SLOTS + 1;
static const size_t MAX_SLOW_NATIVE_EXTRA_SLOTS = 16;
/* Forward declarations of tracer types. */
class VMAllocator;
class FrameInfoCache;
struct REHashFn;
struct REHashKey;
struct FrameInfo;
struct VMSideExit;
struct TreeFragment;
struct TracerState;
template<typename T> class Queue;
typedef Queue<uint16> SlotList;
class TypeMap;
struct REFragment;
typedef nanojit::HashMap<REHashKey, REFragment*, REHashFn> REHashMap;
#if defined(JS_JIT_SPEW) || defined(DEBUG)
struct FragPI;
typedef nanojit::HashMap<uint32, FragPI, nanojit::DefaultHash<uint32> > FragStatsMap;
#endif
/*
* Allocation policy that calls JSContext memory functions and reports errors
* to the context. Since the JSContext given on construction is stored for
* the lifetime of the container, this policy may only be used for containers
* whose lifetime is a shorter than the given JSContext.
*/
class ContextAllocPolicy
{
JSContext *cx;
public:
ContextAllocPolicy(JSContext *cx) : cx(cx) {}
JSContext *context() const { return cx; }
/* Inline definitions below. */
void *malloc(size_t bytes);
void free(void *p);
void *realloc(void *p, size_t bytes);
void reportAllocOverflow() const;
};
/* Holds the execution state during trace execution. */
struct TracerState
{
JSContext* cx; // current VM context handle
double* stackBase; // native stack base
double* sp; // native stack pointer, stack[0] is spbase[0]
double* eos; // first unusable word after the native stack / begin of globals
FrameInfo** callstackBase; // call stack base
void* sor; // start of rp stack
FrameInfo** rp; // call stack pointer
void* eor; // first unusable word after the call stack
VMSideExit* lastTreeExitGuard; // guard we exited on during a tree call
VMSideExit* lastTreeCallGuard; // guard we want to grow from if the tree
// call exit guard mismatched
void* rpAtLastTreeCall; // value of rp at innermost tree call guard
VMSideExit* outermostTreeExitGuard; // the last side exit returned by js_CallTree
TreeFragment* outermostTree; // the outermost tree we initially invoked
uintN* inlineCallCountp; // inline call count counter
VMSideExit** innermostNestedGuardp;
VMSideExit* innermost;
uint64 startTime;
TracerState* prev;
// Used by _FAIL builtins; see jsbuiltins.h. The builtin sets the
// JSBUILTIN_BAILED bit if it bails off trace and the JSBUILTIN_ERROR bit
// if an error or exception occurred.
uint32 builtinStatus;
// Used to communicate the location of the return value in case of a deep bail.
double* deepBailSp;
// Used when calling natives from trace to root the vp vector.
uintN nativeVpLen;
jsval* nativeVp;
// The regs pointed to by cx->regs while a deep-bailed slow native
// completes execution.
JSFrameRegs bailedSlowNativeRegs;
TracerState(JSContext *cx, TraceMonitor *tm, TreeFragment *ti,
uintN &inlineCallCountp, VMSideExit** innermostNestedGuardp);
~TracerState();
};
/*
* Storage for the execution state and store during trace execution. Generated
* code depends on the fact that the globals begin |MAX_NATIVE_STACK_SLOTS|
* doubles after the stack begins. Thus, on trace, |TracerState::eos| holds a
* pointer to the first global.
*/
struct TraceNativeStorage
{
double stack_global_buf[MAX_NATIVE_STACK_SLOTS + GLOBAL_SLOTS_BUFFER_SIZE];
FrameInfo *callstack_buf[MAX_CALL_STACK_ENTRIES];
double *stack() { return stack_global_buf; }
double *global() { return stack_global_buf + MAX_NATIVE_STACK_SLOTS; }
FrameInfo **callstack() { return callstack_buf; }
};
/* Holds data to track a single globa. */
struct GlobalState {
JSObject* globalObj;
uint32 globalShape;
SlotList* globalSlots;
};
/*
* Callstacks
*
* A callstack logically contains the (possibly empty) set of stack frames
* associated with a single activation of the VM and the slots associated with
* each frame. A callstack may or may not be "in" a context and a callstack is
* in a context iff its set of stack frames is nonempty. A callstack and its
* contained frames/slots also have an implied memory layout, as described in
* the js::StackSpace comment.
*
* The set of stack frames in a non-empty callstack start at the callstack's
* "current frame", which is the most recently pushed frame, and ends at the
* callstack's "initial frame". Note that, while all stack frames in a
* callstack are down-linked, not all down-linked frames are in the same
* callstack. Hence, for a callstack |cs|, |cs->getInitialFrame()->down| may be
* non-null and in a different callstack. This occurs when the VM reenters
* itself (via js_Invoke or js_Execute). In full generality, a single context
* may contain a forest of trees of stack frames. With respect to this forest,
* a callstack contains a linear path along a single tree, not necessarily to
* the root.
*
* A callstack in a context may additionally be "active" or "suspended". A
* suspended callstack |cs| has a "suspended frame" which serves as the current
* frame of |cs|. Additionally, a suspended callstack has "suspended regs",
* which is a snapshot of |cx->regs| when |cs| was suspended. There is at most
* one active callstack in a given context. Callstacks in a context execute
* LIFO and are maintained in a stack. The top of this stack is the context's
* "current callstack". If a context |cx| has an active callstack |cs|, then:
* 1. |cs| is |cx|'s current callstack,
* 2. |cx->fp != NULL|, and
* 3. |cs|'s current frame is |cx->fp|.
* Moreover, |cx->fp != NULL| iff |cx| has an active callstack.
*
* Finally, (to support JS_SaveFrameChain/JS_RestoreFrameChain) a suspended
* callstack may or may not be "saved". Normally, when the active callstack is
* popped, the previous callstack (which is necessarily suspended) becomes
* active. If the previous callstack was saved, however, then it stays
* suspended until it is made active by a call to JS_RestoreFrameChain. This is
* why a context may have a current callstack, but not an active callstack.
*/
class CallStack
{
/* The context to which this callstack belongs. */
JSContext *cx;
/* Link for JSContext callstack stack mentioned in big comment above. */
CallStack *previousInContext;
/* Link for StackSpace callstack stack mentioned in StackSpace comment. */
CallStack *previousInThread;
/* The first frame executed in this callstack. null iff cx is null */
JSStackFrame *initialFrame;
/* If this callstack is suspended, the top of the callstack. */
JSStackFrame *suspendedFrame;
/* If this callstack is suspended, |cx->regs| when it was suspended. */
JSFrameRegs *suspendedRegs;
/* This callstack was suspended by JS_SaveFrameChain. */
bool saved;
/* End of arguments before the first frame. See StackSpace comment. */
jsval *initialArgEnd;
/* The varobj on entry to initialFrame. */
JSObject *initialVarObj;
public:
CallStack()
: cx(NULL), previousInContext(NULL), previousInThread(NULL),
initialFrame(NULL), suspendedFrame(NULL), saved(false),
initialArgEnd(NULL), initialVarObj(NULL)
{}
/* Safe casts guaranteed by the contiguous-stack layout. */
jsval *previousCallStackEnd() const {
return (jsval *)this;
}
jsval *getInitialArgBegin() const {
return (jsval *)(this + 1);
}
/*
* As described in the comment at the beginning of the class, a callstack
* is in one of three states:
*
* !inContext: the callstack has been created to root arguments for a
* future call to js_Invoke.
* isActive: the callstack describes a set of stack frames in a context,
* where the top frame currently executing.
* isSuspended: like isActive, but the top frame has been suspended.
*/
bool inContext() const {
JS_ASSERT(!!cx == !!initialFrame);
JS_ASSERT_IF(!initialFrame, !suspendedFrame && !saved);
return cx;
}
bool isActive() const {
JS_ASSERT_IF(suspendedFrame, inContext());
return initialFrame && !suspendedFrame;
}
bool isSuspended() const {
JS_ASSERT_IF(!suspendedFrame, !saved);
JS_ASSERT_IF(suspendedFrame, inContext());
return suspendedFrame;
}
/* Substate of suspended, queryable in any state. */
bool isSaved() const {
JS_ASSERT_IF(saved, isSuspended());
return saved;
}
/* Transitioning between inContext <--> isActive */
void joinContext(JSContext *cx, JSStackFrame *f) {
JS_ASSERT(!inContext());
this->cx = cx;
initialFrame = f;
JS_ASSERT(isActive());
}
void leaveContext() {
JS_ASSERT(isActive());
this->cx = NULL;
initialFrame = NULL;
JS_ASSERT(!inContext());
}
JSContext *maybeContext() const {
return cx;
}
/* Transitioning between isActive <--> isSuspended */
void suspend(JSStackFrame *fp, JSFrameRegs *regs) {
JS_ASSERT(isActive());
JS_ASSERT(fp && contains(fp));
suspendedFrame = fp;
JS_ASSERT(isSuspended());
suspendedRegs = regs;
}
void resume() {
JS_ASSERT(isSuspended());
suspendedFrame = NULL;
JS_ASSERT(isActive());
}
/* When isSuspended, transitioning isSaved <--> !isSaved */
void save(JSStackFrame *fp, JSFrameRegs *regs) {
JS_ASSERT(!isSaved());
suspend(fp, regs);
saved = true;
JS_ASSERT(isSaved());
}
void restore() {
JS_ASSERT(isSaved());
saved = false;
resume();
JS_ASSERT(!isSaved());
}
/* Data available when !inContext */
void setInitialArgEnd(jsval *v) {
JS_ASSERT(!inContext() && !initialArgEnd);
initialArgEnd = v;
}
jsval *getInitialArgEnd() const {
JS_ASSERT(!inContext() && initialArgEnd);
return initialArgEnd;
}
/* Data available when inContext */
JSStackFrame *getInitialFrame() const {
JS_ASSERT(inContext());
return initialFrame;
}
inline JSStackFrame *getCurrentFrame() const;
/* Data available when isSuspended. */
JSStackFrame *getSuspendedFrame() const {
JS_ASSERT(isSuspended());
return suspendedFrame;
}
JSFrameRegs *getSuspendedRegs() const {
JS_ASSERT(isSuspended());
return suspendedRegs;
}
jsval *getSuspendedSP() const {
JS_ASSERT(isSuspended());
return suspendedRegs->sp;
}
/* JSContext / js::StackSpace bookkeeping. */
void setPreviousInContext(CallStack *cs) {
previousInContext = cs;
}
CallStack *getPreviousInContext() const {
return previousInContext;
}
void setPreviousInThread(CallStack *cs) {
previousInThread = cs;
}
CallStack *getPreviousInThread() const {
return previousInThread;
}
void setInitialVarObj(JSObject *obj) {
JS_ASSERT(inContext());
initialVarObj = obj;
}
JSObject *getInitialVarObj() const {
JS_ASSERT(inContext());
return initialVarObj;
}
#ifdef DEBUG
JS_REQUIRES_STACK bool contains(const JSStackFrame *fp) const;
#endif
};
static const size_t VALUES_PER_CALL_STACK = sizeof(CallStack) / sizeof(jsval);
JS_STATIC_ASSERT(sizeof(CallStack) % sizeof(jsval) == 0);
/*
* The ternary constructor is used when arguments are already pushed on the
* stack (as the sp of the current frame), which should only happen from within
* js_Interpret. Otherwise, see StackSpace::pushInvokeArgs.
*/
class InvokeArgsGuard
{
friend class StackSpace;
JSContext *cx;
CallStack *cs; /* null implies nothing pushed */
jsval *vp;
uintN argc;
public:
inline InvokeArgsGuard();
inline InvokeArgsGuard(jsval *vp, uintN argc);
inline ~InvokeArgsGuard();
jsval *getvp() const { return vp; }
uintN getArgc() const { JS_ASSERT(vp != NULL); return argc; }
};
/* See StackSpace::pushInvokeFrame. */
class InvokeFrameGuard
{
friend class StackSpace;
JSContext *cx; /* null implies nothing pushed */
CallStack *cs;
JSStackFrame *fp;
public:
InvokeFrameGuard();
JS_REQUIRES_STACK ~InvokeFrameGuard();
JSStackFrame *getFrame() const { return fp; }
};
/* See StackSpace::pushExecuteFrame. */
class ExecuteFrameGuard
{
friend class StackSpace;
JSContext *cx; /* null implies nothing pushed */
CallStack *cs;
jsval *vp;
JSStackFrame *fp;
JSStackFrame *down;
public:
ExecuteFrameGuard();
JS_REQUIRES_STACK ~ExecuteFrameGuard();
jsval *getvp() const { return vp; }
JSStackFrame *getFrame() const { return fp; }
};
/*
* Thread stack layout
*
* Each JSThreadData has one associated StackSpace object which allocates all
* callstacks for the thread. StackSpace performs all such allocations in a
* single, fixed-size buffer using a specific layout scheme that allows some
* associations between callstacks, frames, and slots to be implicit, rather
* than explicitly stored as pointers. To maintain useful invariants, stack
* space is not given out arbitrarily, but rather allocated/deallocated for
* specific purposes. The use cases currently supported are: calling a function
* with arguments (e.g. js_Invoke), executing a script (e.g. js_Execute) and
* inline interpreter calls. See associated member functions below.
*
* First, we consider the layout of individual callstacks. (See the
* js::CallStack comment for terminology.) A non-empty callstack (i.e., a
* callstack in a context) has the following layout:
*
* initial frame current frame -------. if regs,
* .------------. | | regs->sp
* | V V V
* |callstack| slots |frame| slots |frame| slots |frame| slots |
* | ^ | ^ |
* ? <----------' `----------' `----------'
* down down down
*
* Moreover, the bytes in the following ranges form a contiguous array of
* jsvals that are marked during GC:
* 1. between a callstack and its first frame
* 2. between two adjacent frames in a callstack
* 3. between a callstack's current frame and (if fp->regs) fp->regs->sp
* Thus, the VM must ensure that all such jsvals are safe to be marked.
*
* An empty callstack roots the initial slots before the initial frame is
* pushed and after the initial frame has been popped (perhaps to be followed
* by subsequent initial frame pushes/pops...).
*
* initialArgEnd
* .---------.
* | V
* |callstack| slots |
*
* Above the level of callstacks, a StackSpace is simply a contiguous sequence
* of callstacks kept in a linked list:
*
* base currentCallStack firstUnused end
* | | | |
* V V V V
* |callstack| --- |callstack| --- |callstack| --- | |
* | ^ | ^ |
* 0 <----' `------------' `------------'
* previous previous previous
*
* Both js::StackSpace and JSContext maintain a stack of callstacks, the top of
* which is the "current callstack" for that thread or context, respectively.
* Since different contexts can arbitrarily interleave execution in a single
* thread, these stacks are different enough that a callstack needs both
* "previousInThread" and "previousInContext".
*
* For example, in a single thread, a function in callstack C1 in a context CX1
* may call out into C++ code that reenters the VM in a context CX2, which
* creates a new callstack C2 in CX2, and CX1 may or may not equal CX2.
*
* Note that there is some structure to this interleaving of callstacks:
* 1. the inclusion from callstacks in a context to callstacks in a thread
* preserves order (in terms of previousInContext and previousInThread,
* respectively).
* 2. the mapping from stack frames to their containing callstack preserves
* order (in terms of down and previousInContext, respectively).
*/
class StackSpace
{
jsval *base;
#ifdef XP_WIN
mutable jsval *commitEnd;
#endif
jsval *end;
CallStack *currentCallStack;
/* Although guards are friends, XGuard should only call popX(). */
friend class InvokeArgsGuard;
JS_REQUIRES_STACK inline void popInvokeArgs(JSContext *cx, jsval *vp);
friend class InvokeFrameGuard;
JS_REQUIRES_STACK void popInvokeFrame(JSContext *cx, CallStack *maybecs);
friend class ExecuteFrameGuard;
JS_REQUIRES_STACK void popExecuteFrame(JSContext *cx);
/* Return a pointer to the first unused slot. */
JS_REQUIRES_STACK
inline jsval *firstUnused() const;
inline void assertIsCurrent(JSContext *cx) const;
#ifdef DEBUG
CallStack *getCurrentCallStack() const { return currentCallStack; }
#endif
/*
* Allocate nvals on the top of the stack, report error on failure.
* N.B. the caller must ensure |from == firstUnused()|.
*/
inline bool ensureSpace(JSContext *maybecx, jsval *from, ptrdiff_t nvals) const;
#ifdef XP_WIN
/* Commit more memory from the reserved stack space. */
JS_FRIEND_API(bool) bumpCommit(jsval *from, ptrdiff_t nvals) const;
#endif
public:
static const size_t CAPACITY_VALS = 512 * 1024;
static const size_t CAPACITY_BYTES = CAPACITY_VALS * sizeof(jsval);
static const size_t COMMIT_VALS = 16 * 1024;
static const size_t COMMIT_BYTES = COMMIT_VALS * sizeof(jsval);
/* Kept as a member of JSThreadData; cannot use constructor/destructor. */
bool init();
void finish();
#ifdef DEBUG
template <class T>
bool contains(T *t) const {
char *v = (char *)t;
JS_ASSERT(size_t(-1) - uintptr_t(t) >= sizeof(T));
return v >= (char *)base && v + sizeof(T) <= (char *)end;
}
#endif
/*
* When we LeaveTree, we need to rebuild the stack, which requires stack
* allocation. There is no good way to handle an OOM for these allocations,
* so this function checks that they cannot occur using the size of the
* TraceNativeStorage as a conservative upper bound.
*/
inline bool ensureEnoughSpaceToEnterTrace();
/* +1 for slow native's stack frame. */
static const ptrdiff_t MAX_TRACE_SPACE_VALS =
MAX_NATIVE_STACK_SLOTS + MAX_CALL_STACK_ENTRIES * VALUES_PER_STACK_FRAME +
(VALUES_PER_CALL_STACK + VALUES_PER_STACK_FRAME /* synthesized slow native */);
/* Mark all callstacks, frames, and slots on the stack. */
JS_REQUIRES_STACK void mark(JSTracer *trc);
/*
* For all three use cases below:
* - The boolean-valued functions call js_ReportOutOfScriptQuota on OOM.
* - The "get*Frame" functions do not change any global state, they just
* check OOM and return pointers to an uninitialized frame with the
* requested missing arguments/slots. Only once the "push*Frame"
* function has been called is global state updated. Thus, between
* "get*Frame" and "push*Frame", the frame and slots are unrooted.
* - The "push*Frame" functions will set fp->down; the caller needn't.
* - Functions taking "*Guard" arguments will use the guard's destructor
* to pop the allocation. The caller must ensure the guard has the
* appropriate lifetime.
* - The get*Frame functions put the 'nmissing' slots contiguously after
* the arguments.
*/
/*
* pushInvokeArgs allocates |argc + 2| rooted values that will be passed as
* the arguments to js_Invoke. A single allocation can be used for multiple
* js_Invoke calls. The InvokeArgumentsGuard passed to js_Invoke must come
* from an immediately-enclosing (stack-wise) call to pushInvokeArgs.
*/
JS_REQUIRES_STACK
bool pushInvokeArgs(JSContext *cx, uintN argc, InvokeArgsGuard &ag);
/* These functions are called inside js_Invoke, not js_Invoke clients. */
bool getInvokeFrame(JSContext *cx, const InvokeArgsGuard &ag,
uintN nmissing, uintN nfixed,
InvokeFrameGuard &fg) const;
JS_REQUIRES_STACK
void pushInvokeFrame(JSContext *cx, const InvokeArgsGuard &ag,
InvokeFrameGuard &fg, JSFrameRegs &regs);
/*
* For the simpler case when arguments are allocated at the same time as
* the frame and it is not necessary to have rooted argument values before
* pushing the frame.
*/
JS_REQUIRES_STACK
bool getExecuteFrame(JSContext *cx, JSStackFrame *down,
uintN vplen, uintN nfixed,
ExecuteFrameGuard &fg) const;
JS_REQUIRES_STACK
void pushExecuteFrame(JSContext *cx, ExecuteFrameGuard &fg,
JSFrameRegs &regs, JSObject *initialVarObj);
/*
* Since RAII cannot be used for inline frames, callers must manually
* call pushInlineFrame/popInlineFrame.
*/
JS_REQUIRES_STACK
inline JSStackFrame *getInlineFrame(JSContext *cx, jsval *sp,
uintN nmissing, uintN nfixed) const;
JS_REQUIRES_STACK
inline void pushInlineFrame(JSContext *cx, JSStackFrame *fp, jsbytecode *pc,
JSStackFrame *newfp);
JS_REQUIRES_STACK
inline void popInlineFrame(JSContext *cx, JSStackFrame *up, JSStackFrame *down);
/*
* For the special case of the slow native stack frame pushed and popped by
* tracing deep bail logic.
*/
JS_REQUIRES_STACK
void getSynthesizedSlowNativeFrame(JSContext *cx, CallStack *&cs, JSStackFrame *&fp);
JS_REQUIRES_STACK
void pushSynthesizedSlowNativeFrame(JSContext *cx, CallStack *cs, JSStackFrame *fp,
JSFrameRegs &regs);
JS_REQUIRES_STACK
void popSynthesizedSlowNativeFrame(JSContext *cx);
/* Our privates leak into xpconnect, which needs a public symbol. */
JS_REQUIRES_STACK
JS_FRIEND_API(bool) pushInvokeArgsFriendAPI(JSContext *, uintN, InvokeArgsGuard &);
};
JS_STATIC_ASSERT(StackSpace::CAPACITY_VALS % StackSpace::COMMIT_VALS == 0);
/*
* While |cx->fp|'s pc/sp are available in |cx->regs|, to compute the saved
* value of pc/sp for any other frame, it is necessary to know about that
* frame's up-frame. This iterator maintains this information when walking down
* a chain of stack frames starting at |cx->fp|.
*
* Usage:
* for (FrameRegsIter i(cx); !i.done(); ++i)
* ... i.fp() ... i.sp() ... i.pc()
*/
class FrameRegsIter
{
CallStack *curcs;
JSStackFrame *curfp;
jsval *cursp;
jsbytecode *curpc;
public:
JS_REQUIRES_STACK FrameRegsIter(JSContext *cx);
bool done() const { return curfp == NULL; }
FrameRegsIter &operator++();
JSStackFrame *fp() const { return curfp; }
jsval *sp() const { return cursp; }
jsbytecode *pc() const { return curpc; }
};
/* Holds the number of recording attemps for an address. */
typedef HashMap<jsbytecode*,
size_t,
DefaultHasher<jsbytecode*>,
SystemAllocPolicy> RecordAttemptMap;
class Oracle;
/*
* Trace monitor. Every JSThread (if JS_THREADSAFE) or JSRuntime (if not
* JS_THREADSAFE) has an associated trace monitor that keeps track of loop
* frequencies for all JavaScript code loaded into that runtime.
*/
struct TraceMonitor {
/*
* The context currently executing JIT-compiled code on this thread, or
* NULL if none. Among other things, this can in certain cases prevent
* last-ditch GC and suppress calls to JS_ReportOutOfMemory.
*
* !tracecx && !recorder: not on trace
* !tracecx && recorder: recording
* tracecx && !recorder: executing a trace
* tracecx && recorder: executing inner loop, recording outer loop
*/
JSContext *tracecx;
/*
* Cached storage to use when executing on trace. While we may enter nested
* traces, we always reuse the outer trace's storage, so never need more
* than of these.
*/
TraceNativeStorage *storage;
/*
* There are 5 allocators here. This might seem like overkill, but they
* have different lifecycles, and by keeping them separate we keep the
* amount of retained memory down significantly. They are flushed (ie.
* all the allocated memory is freed) periodically.
*
* - dataAlloc has the lifecycle of the monitor. It's flushed only when
* the monitor is flushed. It's used for fragments.
*
* - traceAlloc has the same flush lifecycle as the dataAlloc, but it is
* also *marked* when a recording starts and rewinds to the mark point
* if recording aborts. So you can put things in it that are only
* reachable on a successful record/compile cycle like GuardRecords and
* SideExits.
*
* - tempAlloc is flushed after each recording, successful or not. It's
* used to store LIR code and for all other elements in the LIR
* pipeline.
*
* - reTempAlloc is just like tempAlloc, but is used for regexp
* compilation in RegExpNativeCompiler rather than normal compilation in
* TraceRecorder.
*
* - codeAlloc has the same lifetime as dataAlloc, but its API is
* different (CodeAlloc vs. VMAllocator). It's used for native code.
* It's also a good idea to keep code and data separate to avoid I-cache
* vs. D-cache issues.
*/
VMAllocator* dataAlloc;
VMAllocator* traceAlloc;
VMAllocator* tempAlloc;
VMAllocator* reTempAlloc;
nanojit::CodeAlloc* codeAlloc;
nanojit::Assembler* assembler;
FrameInfoCache* frameCache;
Oracle* oracle;
TraceRecorder* recorder;
GlobalState globalStates[MONITOR_N_GLOBAL_STATES];
TreeFragment* vmfragments[FRAGMENT_TABLE_SIZE];
RecordAttemptMap* recordAttempts;
/*
* Maximum size of the code cache before we start flushing. 1/16 of this
* size is used as threshold for the regular expression code cache.
*/
uint32 maxCodeCacheBytes;
/*
* If nonzero, do not flush the JIT cache after a deep bail. That would
* free JITted code pages that we will later return to. Instead, set the
* needFlush flag so that it can be flushed later.
*/
JSBool needFlush;
/*
* Fragment map for the regular expression compiler.
*/
REHashMap* reFragments;
// Cached temporary typemap to avoid realloc'ing every time we create one.
// This must be used in only one place at a given time. It must be cleared
// before use.
TypeMap* cachedTempTypeMap;
#ifdef DEBUG
/* Fields needed for fragment/guard profiling. */
nanojit::Seq<nanojit::Fragment*>* branches;
uint32 lastFragID;
/*
* profAlloc has a lifetime which spans exactly from js_InitJIT to
* js_FinishJIT.
*/
VMAllocator* profAlloc;
FragStatsMap* profTab;
#endif
/* Flush the JIT cache. */
void flush();
/* Mark all objects baked into native code in the code cache. */
void mark(JSTracer *trc);
bool outOfMemory() const;
};
} /* namespace js */
/*
* N.B. JS_ON_TRACE(cx) is true if JIT code is on the stack in the current
* thread, regardless of whether cx is the context in which that trace is
* executing. cx must be a context on the current thread.
*/
#ifdef JS_TRACER
# define JS_ON_TRACE(cx) (JS_TRACE_MONITOR(cx).tracecx != NULL)
#else
# define JS_ON_TRACE(cx) JS_FALSE
#endif
#ifdef DEBUG_brendan
# define JS_EVAL_CACHE_METERING 1
# define JS_FUNCTION_METERING 1
#endif
/* Number of potentially reusable scriptsToGC to search for the eval cache. */
#ifndef JS_EVAL_CACHE_SHIFT
# define JS_EVAL_CACHE_SHIFT 6
#endif
#define JS_EVAL_CACHE_SIZE JS_BIT(JS_EVAL_CACHE_SHIFT)
#ifdef JS_EVAL_CACHE_METERING
# define EVAL_CACHE_METER_LIST(_) _(probe), _(hit), _(step), _(noscope)
# define identity(x) x
struct JSEvalCacheMeter {
uint64 EVAL_CACHE_METER_LIST(identity);
};
# undef identity
#endif
#ifdef JS_FUNCTION_METERING
# define FUNCTION_KIND_METER_LIST(_) \
_(allfun), _(heavy), _(nofreeupvar), _(onlyfreevar), \
_(display), _(flat), _(setupvar), _(badfunarg)
# define identity(x) x
struct JSFunctionMeter {
int32 FUNCTION_KIND_METER_LIST(identity);
};
# undef identity
#endif
#define NATIVE_ITER_CACHE_LOG2 8
#define NATIVE_ITER_CACHE_MASK JS_BITMASK(NATIVE_ITER_CACHE_LOG2)
#define NATIVE_ITER_CACHE_SIZE JS_BIT(NATIVE_ITER_CACHE_LOG2)
struct JSPendingProxyOperation {
JSPendingProxyOperation *next;
JSObject *object;
};
struct JSThreadData {
JSGCFreeLists gcFreeLists;
/* Keeper of the contiguous stack used by all contexts in this thread. */
js::StackSpace stackSpace;
/*
* Flag indicating that we are waiving any soft limits on the GC heap
* because we want allocations to be infallible (except when we hit
* a hard quota).
*/
bool waiveGCQuota;
/*
* The GSN cache is per thread since even multi-cx-per-thread embeddings
* do not interleave js_GetSrcNote calls.
*/
JSGSNCache gsnCache;
/* Property cache for faster call/get/set invocation. */
js::PropertyCache propertyCache;
#ifdef JS_TRACER
/* Trace-tree JIT recorder/interpreter state. */
js::TraceMonitor traceMonitor;
#endif
/* Lock-free hashed lists of scripts created by eval to garbage-collect. */
JSScript *scriptsToGC[JS_EVAL_CACHE_SIZE];
#ifdef JS_EVAL_CACHE_METERING
JSEvalCacheMeter evalCacheMeter;
#endif
/* State used by dtoa.c. */
DtoaState *dtoaState;
/*
* State used to cache some double-to-string conversions. A stupid
* optimization aimed directly at v8-splay.js, which stupidly converts
* many doubles multiple times in a row.
*/
struct {
jsdouble d;
jsint base;
JSString *s; // if s==NULL, d and base are not valid
} dtoaCache;
/* Cached native iterators. */
JSObject *cachedNativeIterators[NATIVE_ITER_CACHE_SIZE];
/* Base address of the native stack for the current thread. */
jsuword *nativeStackBase;
/* List of currently pending operations on proxies. */
JSPendingProxyOperation *pendingProxyOperation;
js::ConservativeGCThreadData conservativeGC;
bool init();
void finish();
void mark(JSTracer *trc);
void purge(JSContext *cx);
};
#ifdef JS_THREADSAFE
/*
* Structure uniquely representing a thread. It holds thread-private data
* that can be accessed without a global lock.
*/
struct JSThread {
typedef js::HashMap<void *,
JSThread *,
js::DefaultHasher<void *>,
js::SystemAllocPolicy> Map;
/* Linked list of all contexts in use on this thread. */
JSCList contextList;
/* Opaque thread-id, from NSPR's PR_GetCurrentThread(). */
void *id;
/* Indicates that the thread is waiting in ClaimTitle from jslock.cpp. */
JSTitle *titleToShare;
/*
* Thread-local version of JSRuntime.gcMallocBytes to avoid taking
* locks on each JS_malloc.
*/
ptrdiff_t gcThreadMallocBytes;
/*
* This thread is inside js_GC, either waiting until it can start GC, or
* waiting for GC to finish on another thread. This thread holds no locks;
* other threads may steal titles from it.
*
* Protected by rt->gcLock.
*/
bool gcWaiting;
/*
* Number of JSContext instances that are in requests on this thread. For
* such instances JSContext::requestDepth > 0 holds.
*/
uint32 contextsInRequests;
/* Factored out of JSThread for !JS_THREADSAFE embedding in JSRuntime. */
JSThreadData data;
};
/*
* Only when JSThread::gcThreadMallocBytes exhausts the following limit we
* update JSRuntime::gcMallocBytes.
* .
*/
const size_t JS_GC_THREAD_MALLOC_LIMIT = 1 << 19;
#define JS_THREAD_DATA(cx) (&(cx)->thread->data)
extern JSThread *
js_CurrentThread(JSRuntime *rt);
/*
* The function takes the GC lock and does not release in successful return.
* On error (out of memory) the function releases the lock but delegates
* the error reporting to the caller.
*/
extern JSBool
js_InitContextThread(JSContext *cx);
/*
* On entrance the GC lock must be held and it will be held on exit.
*/
extern void
js_ClearContextThread(JSContext *cx);
#endif /* JS_THREADSAFE */
typedef enum JSDestroyContextMode {
JSDCM_NO_GC,
JSDCM_MAYBE_GC,
JSDCM_FORCE_GC,
JSDCM_NEW_FAILED
} JSDestroyContextMode;
typedef enum JSRuntimeState {
JSRTS_DOWN,
JSRTS_LAUNCHING,
JSRTS_UP,
JSRTS_LANDING
} JSRuntimeState;
typedef struct JSPropertyTreeEntry {
JSDHashEntryHdr hdr;
JSScopeProperty *child;
} JSPropertyTreeEntry;
namespace js {
typedef Vector<JSGCChunkInfo *, 32, SystemAllocPolicy> GCChunks;
struct GCPtrHasher
{
typedef void *Lookup;
static HashNumber hash(void *key) {
return HashNumber(uintptr_t(key) >> JSVAL_TAGBITS);
}
static bool match(void *l, void *k) {
return l == k;
}
};
typedef HashMap<void *, const char *, GCPtrHasher, SystemAllocPolicy> GCRoots;
typedef HashMap<void *, uint32, GCPtrHasher, SystemAllocPolicy> GCLocks;
struct WrapperHasher
{
typedef jsval Lookup;
static HashNumber hash(jsval key) {
return GCPtrHasher::hash(JSVAL_TO_GCTHING(key));
}
static bool match(jsval l, jsval k) {
return l == k;
}
};
typedef HashMap<jsval, jsval, WrapperHasher, SystemAllocPolicy> WrapperMap;
class AutoValueVector;
} /* namespace js */
struct JSCompartment {
JSRuntime *rt;
JSPrincipals *principals;
bool marked;
js::WrapperMap crossCompartmentWrappers;
JSCompartment(JSRuntime *cx);
~JSCompartment();
bool init();
bool wrap(JSContext *cx, jsval *vp);
bool wrap(JSContext *cx, JSString **strp);
bool wrap(JSContext *cx, JSObject **objp);
bool wrapId(JSContext *cx, jsid *idp);
bool wrap(JSContext *cx, JSPropertyOp *op);
bool wrap(JSContext *cx, JSPropertyDescriptor *desc);
bool wrap(JSContext *cx, js::AutoValueVector &props);
bool wrapException(JSContext *cx);
void sweep(JSContext *cx);
};
struct JSRuntime {
/* Default compartment. */
JSCompartment *defaultCompartment;
/* List of compartments (protected by the GC lock). */
js::Vector<JSCompartment *, 0, js::SystemAllocPolicy> compartments;
/* Runtime state, synchronized by the stateChange/gcLock condvar/lock. */
JSRuntimeState state;
/* Context create/destroy callback. */
JSContextCallback cxCallback;
/*
* Shape regenerated whenever a prototype implicated by an "add property"
* property cache fill and induced trace guard has a readonly property or a
* setter defined on it. This number proxies for the shapes of all objects
* along the prototype chain of all objects in the runtime on which such an
* add-property result has been cached/traced.
*
* See bug 492355 for more details.
*
* This comes early in JSRuntime to minimize the immediate format used by
* trace-JITted code that reads it.
*/
uint32 protoHazardShape;
/* Garbage collector state, used by jsgc.c. */
js::GCChunks gcChunks;
size_t gcChunkCursor;
#ifdef DEBUG
JSGCArena *gcEmptyArenaList;
#endif
JSGCArenaList gcArenaList[FINALIZE_LIMIT];
JSGCDoubleArenaList gcDoubleArenaList;
js::GCRoots gcRootsHash;
js::GCLocks gcLocksHash;
jsrefcount gcKeepAtoms;
size_t gcBytes;
size_t gcLastBytes;
size_t gcMaxBytes;
size_t gcMaxMallocBytes;
uint32 gcEmptyArenaPoolLifespan;
uint32 gcNumber;
JSTracer *gcMarkingTracer;
uint32 gcTriggerFactor;
size_t gcTriggerBytes;
volatile JSBool gcIsNeeded;
volatile JSBool gcFlushCodeCaches;
/*
* NB: do not pack another flag here by claiming gcPadding unless the new
* flag is written only by the GC thread. Atomic updates to packed bytes
* are not guaranteed, so stores issued by one thread may be lost due to
* unsynchronized read-modify-write cycles on other threads.
*/
JSPackedBool gcPoke;
JSPackedBool gcRunning;
JSPackedBool gcRegenShapes;
/*
* During gc, if rt->gcRegenShapes &&
* (scope->flags & JSScope::SHAPE_REGEN) == rt->gcRegenShapesScopeFlag,
* then the scope's shape has already been regenerated during this GC.
* To avoid having to sweep JSScopes, the bit's meaning toggles with each
* shape-regenerating GC.
*
* FIXME Once scopes are GC'd (bug 505004), this will be obsolete.
*/
uint8 gcRegenShapesScopeFlag;
#ifdef JS_GC_ZEAL
jsrefcount gcZeal;
#endif
JSGCCallback gcCallback;
/*
* Malloc counter to measure memory pressure for GC scheduling. It runs
* from gcMaxMallocBytes down to zero.
*/
ptrdiff_t gcMallocBytes;
/* See comments before DelayMarkingChildren is jsgc.cpp. */
JSGCArena *gcUnmarkedArenaStackTop;
#ifdef DEBUG
size_t gcMarkLaterCount;
#endif
#ifdef JS_THREADSAFE
JSBackgroundThread gcHelperThread;
#endif
js::GCChunkAllocator *gcChunkAllocator;
void setCustomGCChunkAllocator(js::GCChunkAllocator *allocator) {
JS_ASSERT(allocator);
JS_ASSERT(state == JSRTS_DOWN);
gcChunkAllocator = allocator;
}
/*
* The trace operation and its data argument to trace embedding-specific
* GC roots.
*/
JSTraceDataOp gcExtraRootsTraceOp;
void *gcExtraRootsData;
/* Well-known numbers held for use by this runtime's contexts. */
jsval NaNValue;
jsval negativeInfinityValue;
jsval positiveInfinityValue;
js::DeflatedStringCache *deflatedStringCache;
JSString *emptyString;
/* List of active contexts sharing this runtime; protected by gcLock. */
JSCList contextList;
/* Per runtime debug hooks -- see jsprvtd.h and jsdbgapi.h. */
JSDebugHooks globalDebugHooks;
#ifdef JS_TRACER
/* True if any debug hooks not supported by the JIT are enabled. */
bool debuggerInhibitsJIT() const {
return (globalDebugHooks.interruptHook ||
globalDebugHooks.callHook ||
globalDebugHooks.objectHook);
}
#endif
/* More debugging state, see jsdbgapi.c. */
JSCList trapList;
JSCList watchPointList;
/* Client opaque pointers */
void *data;
#ifdef JS_THREADSAFE
/* These combine to interlock the GC and new requests. */
PRLock *gcLock;
PRCondVar *gcDone;
PRCondVar *requestDone;
uint32 requestCount;
JSThread *gcThread;
/* Lock and owning thread pointer for JS_LOCK_RUNTIME. */
PRLock *rtLock;
#ifdef DEBUG
void * rtLockOwner;
#endif
/* Used to synchronize down/up state change; protected by gcLock. */
PRCondVar *stateChange;
/*
* State for sharing single-threaded titles, once a second thread tries to
* lock a title. The titleSharingDone condvar is protected by rt->gcLock
* to minimize number of locks taken in JS_EndRequest.
*
* The titleSharingTodo linked list is likewise "global" per runtime, not
* one-list-per-context, to conserve space over all contexts, optimizing
* for the likely case that titles become shared rarely, and among a very
* small set of threads (contexts).
*/
PRCondVar *titleSharingDone;
JSTitle *titleSharingTodo;
/*
* Magic terminator for the rt->titleSharingTodo linked list, threaded through
* title->u.link. This hack allows us to test whether a title is on the list
* by asking whether title->u.link is non-null. We use a large, likely bogus
* pointer here to distinguish this value from any valid u.count (small int)
* value.
*/
#define NO_TITLE_SHARING_TODO ((JSTitle *) 0xfeedbeef)
/*
* Lock serializing trapList and watchPointList accesses, and count of all
* mutations to trapList and watchPointList made by debugger threads. To
* keep the code simple, we define debuggerMutations for the thread-unsafe
* case too.
*/
PRLock *debuggerLock;
JSThread::Map threads;
#endif /* JS_THREADSAFE */
uint32 debuggerMutations;
/*
* Security callbacks set on the runtime are used by each context unless
* an override is set on the context.
*/
JSSecurityCallbacks *securityCallbacks;
/*
* Shared scope property tree, and arena-pool for allocating its nodes.
* This really should be free of all locking overhead and allocated in
* thread-local storage, hence the JS_PROPERTY_TREE(cx) macro.
*/
js::PropertyTree propertyTree;
#define JS_PROPERTY_TREE(cx) ((cx)->runtime->propertyTree)
/*
* The propertyRemovals counter is incremented for every JSScope::clear,
* and for each JSScope::remove method call that frees a slot in an object.
* See js_NativeGet and js_NativeSet in jsobj.cpp.
*/
int32 propertyRemovals;
/* Script filename table. */
struct JSHashTable *scriptFilenameTable;
JSCList scriptFilenamePrefixes;
#ifdef JS_THREADSAFE
PRLock *scriptFilenameTableLock;
#endif
/* Number localization, used by jsnum.c */
const char *thousandsSeparator;
const char *decimalSeparator;
const char *numGrouping;
/*
* Weak references to lazily-created, well-known XML singletons.
*
* NB: Singleton objects must be carefully disconnected from the rest of
* the object graph usually associated with a JSContext's global object,
* including the set of standard class objects. See jsxml.c for details.
*/
JSObject *anynameObject;
JSObject *functionNamespaceObject;
#ifndef JS_THREADSAFE
JSThreadData threadData;
#define JS_THREAD_DATA(cx) (&(cx)->runtime->threadData)
#endif
/*
* Object shape (property cache structural type) identifier generator.
*
* Type 0 stands for the empty scope, and must not be regenerated due to
* uint32 wrap-around. Since js_GenerateShape (in jsinterp.cpp) uses
* atomic pre-increment, the initial value for the first typed non-empty
* scope will be 1.
*
* If this counter overflows into SHAPE_OVERFLOW_BIT (in jsinterp.h), the
* cache is disabled, to avoid aliasing two different types. It stays
* disabled until a triggered GC at some later moment compresses live
* types, minimizing rt->shapeGen in the process.
*/
volatile uint32 shapeGen;
/* Literal table maintained by jsatom.c functions. */
JSAtomState atomState;
/*
* Runtime-shared empty scopes for well-known built-in objects that lack
* class prototypes (the usual locus of an emptyScope). Mnemonic: ABCDEW
*/
JSEmptyScope *emptyArgumentsScope;
JSEmptyScope *emptyBlockScope;
JSEmptyScope *emptyCallScope;
JSEmptyScope *emptyDeclEnvScope;
JSEmptyScope *emptyEnumeratorScope;
JSEmptyScope *emptyWithScope;
/*
* Various metering fields are defined at the end of JSRuntime. In this
* way there is no need to recompile all the code that refers to other
* fields of JSRuntime after enabling the corresponding metering macro.
*/
#ifdef JS_DUMP_ENUM_CACHE_STATS
int32 nativeEnumProbes;
int32 nativeEnumMisses;
# define ENUM_CACHE_METER(name) JS_ATOMIC_INCREMENT(&cx->runtime->name)
#else
# define ENUM_CACHE_METER(name) ((void) 0)
#endif
#ifdef JS_DUMP_LOOP_STATS
/* Loop statistics, to trigger trace recording and compiling. */
JSBasicStats loopStats;
#endif
#ifdef DEBUG
/* Function invocation metering. */
jsrefcount inlineCalls;
jsrefcount nativeCalls;
jsrefcount nonInlineCalls;
jsrefcount constructs;
/* Title lock and scope property metering. */
jsrefcount claimAttempts;
jsrefcount claimedTitles;
jsrefcount deadContexts;
jsrefcount deadlocksAvoided;
jsrefcount liveScopes;
jsrefcount sharedTitles;
jsrefcount totalScopes;
jsrefcount liveScopeProps;
jsrefcount liveScopePropsPreSweep;
jsrefcount totalScopeProps;
jsrefcount livePropTreeNodes;
jsrefcount duplicatePropTreeNodes;
jsrefcount totalPropTreeNodes;
jsrefcount propTreeKidsChunks;
/* String instrumentation. */
jsrefcount liveStrings;
jsrefcount totalStrings;
jsrefcount liveDependentStrings;
jsrefcount totalDependentStrings;
jsrefcount badUndependStrings;
double lengthSum;
double lengthSquaredSum;
double strdepLengthSum;
double strdepLengthSquaredSum;
/* Script instrumentation. */
jsrefcount liveScripts;
jsrefcount totalScripts;
jsrefcount liveEmptyScripts;
jsrefcount totalEmptyScripts;
#endif /* DEBUG */
#ifdef JS_SCOPE_DEPTH_METER
/*
* Stats on runtime prototype chain lookups and scope chain depths, i.e.,
* counts of objects traversed on a chain until the wanted id is found.
*/
JSBasicStats protoLookupDepthStats;
JSBasicStats scopeSearchDepthStats;
/*
* Stats on compile-time host environment and lexical scope chain lengths
* (maximum depths).
*/
JSBasicStats hostenvScopeDepthStats;
JSBasicStats lexicalScopeDepthStats;
#endif
#ifdef JS_GCMETER
JSGCStats gcStats;
#endif
#ifdef JS_FUNCTION_METERING
JSFunctionMeter functionMeter;
char lastScriptFilename[1024];
#endif
JSWrapObjectCallback wrapObjectCallback;
JSRuntime();
~JSRuntime();
bool init(uint32 maxbytes);
void setGCTriggerFactor(uint32 factor);
void setGCLastBytes(size_t lastBytes);
void* malloc(size_t bytes) { return ::js_malloc(bytes); }
void* calloc(size_t bytes) { return ::js_calloc(bytes); }
void* realloc(void* p, size_t bytes) { return ::js_realloc(p, bytes); }
void free(void* p) { ::js_free(p); }
bool isGCMallocLimitReached() const { return gcMallocBytes <= 0; }
void resetGCMallocBytes() { gcMallocBytes = ptrdiff_t(gcMaxMallocBytes); }
void setGCMaxMallocBytes(size_t value) {
/*
* For compatibility treat any value that exceeds PTRDIFF_T_MAX to
* mean that value.
*/
gcMaxMallocBytes = (ptrdiff_t(value) >= 0) ? value : size_t(-1) >> 1;
resetGCMallocBytes();
}
};
/* Common macros to access thread-local caches in JSThread or JSRuntime. */
#define JS_GSN_CACHE(cx) (JS_THREAD_DATA(cx)->gsnCache)
#define JS_PROPERTY_CACHE(cx) (JS_THREAD_DATA(cx)->propertyCache)
#define JS_TRACE_MONITOR(cx) (JS_THREAD_DATA(cx)->traceMonitor)
#define JS_SCRIPTS_TO_GC(cx) (JS_THREAD_DATA(cx)->scriptsToGC)
#ifdef JS_EVAL_CACHE_METERING
# define EVAL_CACHE_METER(x) (JS_THREAD_DATA(cx)->evalCacheMeter.x++)
#else
# define EVAL_CACHE_METER(x) ((void) 0)
#endif
#ifdef DEBUG
# define JS_RUNTIME_METER(rt, which) JS_ATOMIC_INCREMENT(&(rt)->which)
# define JS_RUNTIME_UNMETER(rt, which) JS_ATOMIC_DECREMENT(&(rt)->which)
#else
# define JS_RUNTIME_METER(rt, which) /* nothing */
# define JS_RUNTIME_UNMETER(rt, which) /* nothing */
#endif
#define JS_KEEP_ATOMS(rt) JS_ATOMIC_INCREMENT(&(rt)->gcKeepAtoms);
#define JS_UNKEEP_ATOMS(rt) JS_ATOMIC_DECREMENT(&(rt)->gcKeepAtoms);
#ifdef JS_ARGUMENT_FORMATTER_DEFINED
/*
* Linked list mapping format strings for JS_{Convert,Push}Arguments{,VA} to
* formatter functions. Elements are sorted in non-increasing format string
* length order.
*/
struct JSArgumentFormatMap {
const char *format;
size_t length;
JSArgumentFormatter formatter;
JSArgumentFormatMap *next;
};
#endif
/*
* Key and entry types for the JSContext.resolvingTable hash table, typedef'd
* here because all consumers need to see these declarations (and not just the
* typedef names, as would be the case for an opaque pointer-to-typedef'd-type
* declaration), along with cx->resolvingTable.
*/
typedef struct JSResolvingKey {
JSObject *obj;
jsid id;
} JSResolvingKey;
typedef struct JSResolvingEntry {
JSDHashEntryHdr hdr;
JSResolvingKey key;
uint32 flags;
} JSResolvingEntry;
#define JSRESFLAG_LOOKUP 0x1 /* resolving id from lookup */
#define JSRESFLAG_WATCH 0x2 /* resolving id from watch */
#define JSRESOLVE_INFER 0xffff /* infer bits from current bytecode */
extern const JSDebugHooks js_NullDebugHooks; /* defined in jsdbgapi.cpp */
namespace js {
class AutoGCRooter;
}
struct JSRegExpStatics {
JSContext *cx;
JSString *input; /* input string to match (perl $_, GC root) */
JSBool multiline; /* whether input contains newlines (perl $*) */
JSSubString lastMatch; /* last string matched (perl $&) */
JSSubString lastParen; /* last paren matched (perl $+) */
JSSubString leftContext; /* input to left of last match (perl $`) */
JSSubString rightContext; /* input to right of last match (perl $') */
js::Vector<JSSubString> parens; /* last set of parens matched (perl $1, $2) */
JSRegExpStatics(JSContext *cx) : cx(cx), parens(cx) {}
bool copy(const JSRegExpStatics& other);
void clearRoots();
void clear();
};
struct JSContext
{
explicit JSContext(JSRuntime *rt);
/*
* If this flag is set, we were asked to call back the operation callback
* as soon as possible.
*/
volatile jsint operationCallbackFlag;
/* JSRuntime contextList linkage. */
JSCList link;
/*
* Classic Algol "display" static link optimization.
*/
#define JS_DISPLAY_SIZE 16U
JSStackFrame *display[JS_DISPLAY_SIZE];
/* Runtime version control identifier. */
uint16 version;
/* Per-context options. */
uint32 options; /* see jsapi.h for JSOPTION_* */
/* Locale specific callbacks for string conversion. */
JSLocaleCallbacks *localeCallbacks;
/*
* cx->resolvingTable is non-null and non-empty if we are initializing
* standard classes lazily, or if we are otherwise recursing indirectly
* from js_LookupProperty through a JSClass.resolve hook. It is used to
* limit runaway recursion (see jsapi.c and jsobj.c).
*/
JSDHashTable *resolvingTable;
/*
* True if generating an error, to prevent runaway recursion.
* NB: generatingError packs with insideGCMarkCallback and throwing below.
*/
JSPackedBool generatingError;
/* Flag to indicate that we run inside gcCallback(cx, JSGC_MARK_END). */
JSPackedBool insideGCMarkCallback;
/* Exception state -- the exception member is a GC root by definition. */
JSPackedBool throwing; /* is there a pending exception? */
jsval exception; /* most-recently-thrown exception */
/* Limit pointer for checking native stack consumption during recursion. */
jsuword stackLimit;
/* Quota on the size of arenas used to compile and execute scripts. */
size_t scriptStackQuota;
/* Data shared by threads in an address space. */
JSRuntime *const runtime;
/* GC heap compartment. */
JSCompartment *compartment;
/* Currently executing frame, set by stack operations. */
JS_REQUIRES_STACK
JSStackFrame *fp;
/*
* Currently executing frame's regs, set by stack operations.
* |fp != NULL| iff |regs != NULL| (although regs->pc can be NULL)
*/
JS_REQUIRES_STACK
JSFrameRegs *regs;
private:
friend class js::StackSpace;
friend JSBool js_Interpret(JSContext *);
/* 'fp' and 'regs' must only be changed by calling these functions. */
void setCurrentFrame(JSStackFrame *fp) {
this->fp = fp;
}
void setCurrentRegs(JSFrameRegs *regs) {
this->regs = regs;
}
public:
/* Temporary arena pool used while compiling and decompiling. */
JSArenaPool tempPool;
/* Top-level object and pointer to top stack frame's scope chain. */
JSObject *globalObject;
/* Storage to root recently allocated GC things and script result. */
JSWeakRoots weakRoots;
/* Regular expression class statics. */
JSRegExpStatics regExpStatics;
/* State for object and array toSource conversion. */
JSSharpObjectMap sharpObjectMap;
js::HashSet<JSObject *> busyArrays;
/* Argument formatter support for JS_{Convert,Push}Arguments{,VA}. */
JSArgumentFormatMap *argumentFormatMap;
/* Last message string and trace file for debugging. */
char *lastMessage;
#ifdef DEBUG
void *tracefp;
jsbytecode *tracePrevPc;
#endif
/* Per-context optional error reporter. */
JSErrorReporter errorReporter;
/* Branch callback. */
JSOperationCallback operationCallback;
/* Interpreter activation count. */
uintN interpLevel;
/* Client opaque pointers. */
void *data;
void *data2;
private:
/* Linked list of callstacks. See CallStack. */
js::CallStack *currentCallStack;
public:
void assertCallStacksInSync() const {
#ifdef DEBUG
if (fp) {
JS_ASSERT(currentCallStack->isActive());
if (js::CallStack *prev = currentCallStack->getPreviousInContext())
JS_ASSERT(!prev->isActive());
} else {
JS_ASSERT_IF(currentCallStack, !currentCallStack->isActive());
}
#endif
}
/* Return whether this context has an active callstack. */
bool hasActiveCallStack() const {
assertCallStacksInSync();
return fp;
}
/* Assuming there is an active callstack, return it. */
js::CallStack *activeCallStack() const {
JS_ASSERT(hasActiveCallStack());
return currentCallStack;
}
/* Return the current callstack, which may or may not be active. */
js::CallStack *getCurrentCallStack() const {
assertCallStacksInSync();
return currentCallStack;
}
/* Add the given callstack to the list as the new active callstack. */
void pushCallStackAndFrame(js::CallStack *newcs, JSStackFrame *newfp,
JSFrameRegs &regs);
/* Remove the active callstack and make the next callstack active. */
void popCallStackAndFrame();
/* Mark the top callstack as suspended, without pushing a new one. */
void saveActiveCallStack();
/* Undoes calls to suspendTopCallStack. */
void restoreCallStack();
/*
* Perform a linear search of all frames in all callstacks in the given context
* for the given frame, returning the callstack, if found, and null otherwise.
*/
js::CallStack *containingCallStack(const JSStackFrame *target);
#ifdef JS_THREADSAFE
JSThread *thread;
jsrefcount requestDepth;
/* Same as requestDepth but ignoring JS_SuspendRequest/JS_ResumeRequest */
jsrefcount outstandingRequests;
# ifdef DEBUG
unsigned checkRequestDepth;
# endif
JSTitle *lockedSealedTitle; /* weak ref, for low-cost sealed
title locking */
JSCList threadLinks; /* JSThread contextList linkage */
#define CX_FROM_THREAD_LINKS(tl) \
((JSContext *)((char *)(tl) - offsetof(JSContext, threadLinks)))
#endif
/* Stack of thread-stack-allocated GC roots. */
js::AutoGCRooter *autoGCRooters;
/* Debug hooks associated with the current context. */
const JSDebugHooks *debugHooks;
/* Security callbacks that override any defined on the runtime. */
JSSecurityCallbacks *securityCallbacks;
/* Pinned regexp pool used for regular expressions. */
JSArenaPool regexpPool;
/* Stored here to avoid passing it around as a parameter. */
uintN resolveFlags;
/* Random number generator state, used by jsmath.cpp. */
int64 rngSeed;
/* Location to stash the iteration value between JSOP_MOREITER and JSOP_FOR*. */
jsval iterValue;
#ifdef JS_TRACER
/*
* State for the current tree execution. bailExit is valid if the tree has
* called back into native code via a _FAIL builtin and has not yet bailed,
* else garbage (NULL in debug builds).
*/
js::TracerState *tracerState;
js::VMSideExit *bailExit;
/*
* True if traces may be executed. Invariant: The value of jitEnabled is
* always equal to the expression in updateJITEnabled below.
*
* This flag and the fields accessed by updateJITEnabled are written only
* in runtime->gcLock, to avoid race conditions that would leave the wrong
* value in jitEnabled. (But the interpreter reads this without
* locking. That can race against another thread setting debug hooks, but
* we always read cx->debugHooks without locking anyway.)
*/
bool jitEnabled;
#endif
/* Caller must be holding runtime->gcLock. */
void updateJITEnabled() {
#ifdef JS_TRACER
jitEnabled = ((options & JSOPTION_JIT) &&
(debugHooks == &js_NullDebugHooks ||
(debugHooks == &runtime->globalDebugHooks &&
!runtime->debuggerInhibitsJIT())));
#endif
}
DSTOffsetCache dstOffsetCache;
/* List of currently active non-escaping enumerators (for-in). */
JSObject *enumerators;
private:
/*
* To go from a live generator frame (on the stack) to its generator object
* (see comment js_FloatingFrameIfGenerator), we maintain a stack of active
* generators, pushing and popping when entering and leaving generator
* frames, respectively.
*/
js::Vector<JSGenerator *, 2, js::SystemAllocPolicy> genStack;
public:
/* Return the generator object for the given generator frame. */
JSGenerator *generatorFor(JSStackFrame *fp) const;
/* Early OOM-check. */
inline bool ensureGeneratorStackSpace();
bool enterGenerator(JSGenerator *gen) {
return genStack.append(gen);
}
void leaveGenerator(JSGenerator *gen) {
JS_ASSERT(genStack.back() == gen);
genStack.popBack();
}
#ifdef JS_THREADSAFE
/*
* The sweep task for this context.
*/
js::BackgroundSweepTask *gcSweepTask;
#endif
ptrdiff_t &getMallocCounter() {
#ifdef JS_THREADSAFE
return thread->gcThreadMallocBytes;
#else
return runtime->gcMallocBytes;
#endif
}
/*
* Call this after allocating memory held by GC things, to update memory
* pressure counters or report the OOM error if necessary.
*/
inline void updateMallocCounter(void *p, size_t nbytes) {
JS_ASSERT(ptrdiff_t(nbytes) >= 0);
ptrdiff_t &counter = getMallocCounter();
counter -= ptrdiff_t(nbytes);
if (!p || counter <= 0)
checkMallocGCPressure(p);
}
/*
* Call this after successfully allocating memory held by GC things, to
* update memory pressure counters.
*/
inline void updateMallocCounter(size_t nbytes) {
JS_ASSERT(ptrdiff_t(nbytes) >= 0);
ptrdiff_t &counter = getMallocCounter();
counter -= ptrdiff_t(nbytes);
if (counter <= 0) {
/*
* Use 1 as an arbitrary non-null pointer indicating successful
* allocation.
*/
checkMallocGCPressure(reinterpret_cast<void *>(jsuword(1)));
}
}
inline void* malloc(size_t bytes) {
JS_ASSERT(bytes != 0);
void *p = runtime->malloc(bytes);
updateMallocCounter(p, bytes);
return p;
}
inline void* mallocNoReport(size_t bytes) {
JS_ASSERT(bytes != 0);
void *p = runtime->malloc(bytes);
if (!p)
return NULL;
updateMallocCounter(bytes);
return p;
}
inline void* calloc(size_t bytes) {
JS_ASSERT(bytes != 0);
void *p = runtime->calloc(bytes);
updateMallocCounter(p, bytes);
return p;
}
inline void* realloc(void* p, size_t bytes) {
void *orig = p;
p = runtime->realloc(p, bytes);
/*
* For compatibility we do not account for realloc that increases
* previously allocated memory.
*/
updateMallocCounter(p, orig ? 0 : bytes);
return p;
}
inline void free(void* p) {
#ifdef JS_THREADSAFE
if (gcSweepTask) {
gcSweepTask->freeLater(p);
return;
}
#endif
runtime->free(p);
}
/*
* In the common case that we'd like to allocate the memory for an object
* with cx->malloc/free, we cannot use overloaded C++ operators (no
* placement delete). Factor the common workaround into one place.
*/
#define CREATE_BODY(parms) \
void *memory = this->malloc(sizeof(T)); \
if (!memory) \
return NULL; \
return new(memory) T parms;
template <class T>
JS_ALWAYS_INLINE T *create() {
CREATE_BODY(())
}
template <class T, class P1>
JS_ALWAYS_INLINE T *create(const P1 &p1) {
CREATE_BODY((p1))
}
template <class T, class P1, class P2>
JS_ALWAYS_INLINE T *create(const P1 &p1, const P2 &p2) {
CREATE_BODY((p1, p2))
}
template <class T, class P1, class P2, class P3>
JS_ALWAYS_INLINE T *create(const P1 &p1, const P2 &p2, const P3 &p3) {
CREATE_BODY((p1, p2, p3))
}
#undef CREATE_BODY
template <class T>
JS_ALWAYS_INLINE void destroy(T *p) {
p->~T();
this->free(p);
}
bool isConstructing();
void purge();
js::StackSpace &stack() const {
return JS_THREAD_DATA(this)->stackSpace;
}
#ifdef DEBUG
void assertValidStackDepth(uintN depth) {
JS_ASSERT(0 <= regs->sp - StackBase(fp));
JS_ASSERT(depth <= uintptr_t(regs->sp - StackBase(fp)));
}
#else
void assertValidStackDepth(uintN /*depth*/) {}
#endif
private:
/*
* The allocation code calls the function to indicate either OOM failure
* when p is null or that a memory pressure counter has reached some
* threshold when p is not null. The function takes the pointer and not
* a boolean flag to minimize the amount of code in its inlined callers.
*/
void checkMallocGCPressure(void *p);
};
JS_ALWAYS_INLINE JSObject *
JSStackFrame::varobj(js::CallStack *cs) const
{
JS_ASSERT(cs->contains(this));
return fun ? callobj : cs->getInitialVarObj();
}
JS_ALWAYS_INLINE JSObject *
JSStackFrame::varobj(JSContext *cx) const
{
JS_ASSERT(cx->activeCallStack()->contains(this));
return fun ? callobj : cx->activeCallStack()->getInitialVarObj();
}
JS_ALWAYS_INLINE jsbytecode *
JSStackFrame::pc(JSContext *cx) const
{
JS_ASSERT(cx->containingCallStack(this) != NULL);
return cx->fp == this ? cx->regs->pc : savedPC;
}
/*
* InvokeArgsGuard is used outside the JS engine (where jscntxtinlines.h is
* not included). To avoid visibility issues, force members inline.
*/
namespace js {
JS_ALWAYS_INLINE void
StackSpace::popInvokeArgs(JSContext *cx, jsval *vp)
{
JS_ASSERT(!currentCallStack->inContext());
currentCallStack = currentCallStack->getPreviousInThread();
}
JS_ALWAYS_INLINE
InvokeArgsGuard::InvokeArgsGuard()
: cx(NULL), cs(NULL), vp(NULL)
{}
JS_ALWAYS_INLINE
InvokeArgsGuard::InvokeArgsGuard(jsval *vp, uintN argc)
: cx(NULL), cs(NULL), vp(vp), argc(argc)
{}
JS_ALWAYS_INLINE
InvokeArgsGuard::~InvokeArgsGuard()
{
if (!cs)
return;
JS_ASSERT(cs == cx->stack().getCurrentCallStack());
cx->stack().popInvokeArgs(cx, vp);
}
} /* namespace js */
#ifdef JS_THREADSAFE
# define JS_THREAD_ID(cx) ((cx)->thread ? (cx)->thread->id : 0)
#endif
#if defined JS_THREADSAFE && defined DEBUG
namespace js {
class AutoCheckRequestDepth {
JSContext *cx;
public:
AutoCheckRequestDepth(JSContext *cx) : cx(cx) { cx->checkRequestDepth++; }
~AutoCheckRequestDepth() {
JS_ASSERT(cx->checkRequestDepth != 0);
cx->checkRequestDepth--;
}
};
}
# define CHECK_REQUEST(cx) \
JS_ASSERT((cx)->requestDepth || (cx)->thread == (cx)->runtime->gcThread);\
AutoCheckRequestDepth _autoCheckRequestDepth(cx);
#else
# define CHECK_REQUEST(cx) ((void)0)
#endif
static inline uintN
FramePCOffset(JSContext *cx, JSStackFrame* fp)
{
return uintN((fp->imacpc ? fp->imacpc : fp->pc(cx)) - fp->script->code);
}
static inline JSAtom **
FrameAtomBase(JSContext *cx, JSStackFrame *fp)
{
return fp->imacpc
? COMMON_ATOMS_START(&cx->runtime->atomState)
: fp->script->atomMap.vector;
}
namespace js {
class AutoGCRooter {
public:
AutoGCRooter(JSContext *cx, ptrdiff_t tag)
: down(cx->autoGCRooters), tag(tag), context(cx)
{
JS_ASSERT(this != cx->autoGCRooters);
cx->autoGCRooters = this;
}
~AutoGCRooter() {
JS_ASSERT(this == context->autoGCRooters);
context->autoGCRooters = down;
}
/* Implemented in jsgc.cpp. */
inline void trace(JSTracer *trc);
#ifdef __GNUC__
# pragma GCC visibility push(default)
#endif
friend void ::js_TraceContext(JSTracer *trc, JSContext *acx);
#ifdef __GNUC__
# pragma GCC visibility pop
#endif
protected:
AutoGCRooter * const down;
/*
* Discriminates actual subclass of this being used. If non-negative, the
* subclass roots an array of jsvals of the length stored in this field.
* If negative, meaning is indicated by the corresponding value in the enum
* below. Any other negative value indicates some deeper problem such as
* memory corruption.
*/
ptrdiff_t tag;
JSContext * const context;
enum {
JSVAL = -1, /* js::AutoValueRooter */
SPROP = -2, /* js::AutoScopePropertyRooter */
WEAKROOTS = -3, /* js::AutoSaveWeakRoots */
PARSER = -4, /* js::Parser */
SCRIPT = -5, /* js::AutoScriptRooter */
ENUMERATOR = -6, /* js::AutoEnumStateRooter */
IDARRAY = -7, /* js::AutoIdArray */
DESCRIPTORS = -8, /* js::AutoDescriptorArray */
NAMESPACES = -9, /* js::AutoNamespaceArray */
XML = -10, /* js::AutoXMLRooter */
OBJECT = -11, /* js::AutoObjectRooter */
ID = -12, /* js::AutoIdRooter */
VECTOR = -13, /* js::AutoValueVector */
DESCRIPTOR = -14 /* js::AutoDescriptor */
};
private:
/* No copy or assignment semantics. */
AutoGCRooter(AutoGCRooter &ida);
void operator=(AutoGCRooter &ida);
};
class AutoPreserveWeakRoots : private AutoGCRooter
{
public:
explicit AutoPreserveWeakRoots(JSContext *cx
JS_GUARD_OBJECT_NOTIFIER_PARAM)
: AutoGCRooter(cx, WEAKROOTS), savedRoots(cx->weakRoots)
{
JS_GUARD_OBJECT_NOTIFIER_INIT;
}
~AutoPreserveWeakRoots()
{
context->weakRoots = savedRoots;
}
friend void AutoGCRooter::trace(JSTracer *trc);
private:
JSWeakRoots savedRoots;
JS_DECL_USE_GUARD_OBJECT_NOTIFIER
};
/* FIXME(bug 332648): Move this into a public header. */
class AutoValueRooter : private AutoGCRooter
{
public:
explicit AutoValueRooter(JSContext *cx, jsval v = JSVAL_NULL
JS_GUARD_OBJECT_NOTIFIER_PARAM)
: AutoGCRooter(cx, JSVAL), val(v)
{
JS_GUARD_OBJECT_NOTIFIER_INIT;
}
AutoValueRooter(JSContext *cx, JSString *str
JS_GUARD_OBJECT_NOTIFIER_PARAM)
: AutoGCRooter(cx, JSVAL), val(STRING_TO_JSVAL(str))
{
JS_GUARD_OBJECT_NOTIFIER_INIT;
}
AutoValueRooter(JSContext *cx, JSObject *obj
JS_GUARD_OBJECT_NOTIFIER_PARAM)
: AutoGCRooter(cx, JSVAL), val(OBJECT_TO_JSVAL(obj))
{
JS_GUARD_OBJECT_NOTIFIER_INIT;
}
void set(jsval v) {
JS_ASSERT(tag == JSVAL);
val = v;
}
void setObject(JSObject *obj) {
JS_ASSERT(tag == JSVAL);
val = OBJECT_TO_JSVAL(obj);
}
void setString(JSString *str) {
JS_ASSERT(tag == JSVAL);
JS_ASSERT(str);
val = STRING_TO_JSVAL(str);
}
void setDouble(jsdouble *dp) {
JS_ASSERT(tag == JSVAL);
JS_ASSERT(dp);
val = DOUBLE_TO_JSVAL(dp);
}
jsval value() const {
JS_ASSERT(tag == JSVAL);
return val;
}
jsval *addr() {
JS_ASSERT(tag == JSVAL);
return &val;
}
friend void AutoGCRooter::trace(JSTracer *trc);
private:
jsval val;
JS_DECL_USE_GUARD_OBJECT_NOTIFIER
};
class AutoObjectRooter : private AutoGCRooter {
public:
AutoObjectRooter(JSContext *cx, JSObject *obj = NULL
JS_GUARD_OBJECT_NOTIFIER_PARAM)
: AutoGCRooter(cx, OBJECT), obj(obj)
{
JS_GUARD_OBJECT_NOTIFIER_INIT;
}
void setObject(JSObject *obj) {
this->obj = obj;
}
JSObject * object() const {
return obj;
}
JSObject ** addr() {
return &obj;
}
friend void AutoGCRooter::trace(JSTracer *trc);
private:
JSObject *obj;
JS_DECL_USE_GUARD_OBJECT_NOTIFIER
};
class AutoArrayRooter : private AutoGCRooter {
public:
AutoArrayRooter(JSContext *cx, size_t len, jsval *vec
JS_GUARD_OBJECT_NOTIFIER_PARAM)
: AutoGCRooter(cx, len), array(vec)
{
JS_GUARD_OBJECT_NOTIFIER_INIT;
JS_ASSERT(tag >= 0);
}
void changeLength(size_t newLength) {
tag = ptrdiff_t(newLength);
JS_ASSERT(tag >= 0);
}
void changeArray(jsval *newArray, size_t newLength) {
changeLength(newLength);
array = newArray;
}
jsval *array;
friend void AutoGCRooter::trace(JSTracer *trc);
private:
JS_DECL_USE_GUARD_OBJECT_NOTIFIER
};
class AutoScopePropertyRooter : private AutoGCRooter {
public:
AutoScopePropertyRooter(JSContext *cx, JSScopeProperty *sprop
JS_GUARD_OBJECT_NOTIFIER_PARAM)
: AutoGCRooter(cx, SPROP), sprop(sprop)
{
JS_GUARD_OBJECT_NOTIFIER_INIT;
}
friend void AutoGCRooter::trace(JSTracer *trc);
private:
JSScopeProperty * const sprop;
JS_DECL_USE_GUARD_OBJECT_NOTIFIER
};
class AutoScriptRooter : private AutoGCRooter {
public:
AutoScriptRooter(JSContext *cx, JSScript *script
JS_GUARD_OBJECT_NOTIFIER_PARAM)
: AutoGCRooter(cx, SCRIPT), script(script)
{
JS_GUARD_OBJECT_NOTIFIER_INIT;
}
void setScript(JSScript *script) {
this->script = script;
}
friend void AutoGCRooter::trace(JSTracer *trc);
private:
JSScript *script;
JS_DECL_USE_GUARD_OBJECT_NOTIFIER
};
class AutoIdRooter : private AutoGCRooter
{
public:
explicit AutoIdRooter(JSContext *cx, jsid id = INT_TO_JSID(0)
JS_GUARD_OBJECT_NOTIFIER_PARAM)
: AutoGCRooter(cx, ID), idval(id)
{
JS_GUARD_OBJECT_NOTIFIER_INIT;
}
jsid id() {
return idval;
}
jsid * addr() {
return &idval;
}
friend void AutoGCRooter::trace(JSTracer *trc);
private:
jsid idval;
JS_DECL_USE_GUARD_OBJECT_NOTIFIER
};
class AutoIdArray : private AutoGCRooter {
public:
AutoIdArray(JSContext *cx, JSIdArray *ida JS_GUARD_OBJECT_NOTIFIER_PARAM)
: AutoGCRooter(cx, IDARRAY), idArray(ida)
{
JS_GUARD_OBJECT_NOTIFIER_INIT;
}
~AutoIdArray() {
if (idArray)
JS_DestroyIdArray(context, idArray);
}
bool operator!() {
return idArray == NULL;
}
jsid operator[](size_t i) const {
JS_ASSERT(idArray);
JS_ASSERT(i < size_t(idArray->length));
return idArray->vector[i];
}
size_t length() const {
return idArray->length;
}
friend void AutoGCRooter::trace(JSTracer *trc);
JSIdArray *steal() {
JSIdArray *copy = idArray;
idArray = NULL;
return copy;
}
protected:
inline void trace(JSTracer *trc);
private:
JSIdArray * idArray;
JS_DECL_USE_GUARD_OBJECT_NOTIFIER
/* No copy or assignment semantics. */
AutoIdArray(AutoIdArray &ida);
void operator=(AutoIdArray &ida);
};
/* The auto-root for enumeration object and its state. */
class AutoEnumStateRooter : private AutoGCRooter
{
public:
AutoEnumStateRooter(JSContext *cx, JSObject *obj
JS_GUARD_OBJECT_NOTIFIER_PARAM)
: AutoGCRooter(cx, ENUMERATOR), obj(obj), stateValue(JSVAL_NULL)
{
JS_GUARD_OBJECT_NOTIFIER_INIT;
JS_ASSERT(obj);
}
~AutoEnumStateRooter() {
if (!JSVAL_IS_NULL(stateValue)) {
#ifdef DEBUG
JSBool ok =
#endif
obj->enumerate(context, JSENUMERATE_DESTROY, &stateValue, 0);
JS_ASSERT(ok);
}
}
friend void AutoGCRooter::trace(JSTracer *trc);
jsval state() const { return stateValue; }
jsval * addr() { return &stateValue; }
protected:
void trace(JSTracer *trc) {
JS_CALL_OBJECT_TRACER(trc, obj, "js::AutoEnumStateRooter.obj");
}
JSObject * const obj;
private:
jsval stateValue;
JS_DECL_USE_GUARD_OBJECT_NOTIFIER
};
#ifdef JS_HAS_XML_SUPPORT
class AutoXMLRooter : private AutoGCRooter {
public:
AutoXMLRooter(JSContext *cx, JSXML *xml)
: AutoGCRooter(cx, XML), xml(xml)
{
JS_ASSERT(xml);
}
friend void AutoGCRooter::trace(JSTracer *trc);
private:
JSXML * const xml;
};
#endif /* JS_HAS_XML_SUPPORT */
class AutoLockGC {
private:
JSRuntime *rt;
public:
explicit AutoLockGC(JSRuntime *rt) : rt(rt) { JS_LOCK_GC(rt); }
~AutoLockGC() { JS_UNLOCK_GC(rt); }
};
class AutoUnlockGC {
private:
JSRuntime *rt;
public:
explicit AutoUnlockGC(JSRuntime *rt) : rt(rt) { JS_UNLOCK_GC(rt); }
~AutoUnlockGC() { JS_LOCK_GC(rt); }
};
class AutoKeepAtoms {
JSRuntime *rt;
public:
explicit AutoKeepAtoms(JSRuntime *rt) : rt(rt) { JS_KEEP_ATOMS(rt); }
~AutoKeepAtoms() { JS_UNKEEP_ATOMS(rt); }
};
} /* namespace js */
class JSAutoResolveFlags
{
public:
JSAutoResolveFlags(JSContext *cx, uintN flags
JS_GUARD_OBJECT_NOTIFIER_PARAM)
: mContext(cx), mSaved(cx->resolveFlags)
{
JS_GUARD_OBJECT_NOTIFIER_INIT;
cx->resolveFlags = flags;
}
~JSAutoResolveFlags() { mContext->resolveFlags = mSaved; }
private:
JSContext *mContext;
uintN mSaved;
JS_DECL_USE_GUARD_OBJECT_NOTIFIER
};
/*
* Slightly more readable macros for testing per-context option settings (also
* to hide bitset implementation detail).
*
* JSOPTION_XML must be handled specially in order to propagate from compile-
* to run-time (from cx->options to script->version/cx->version). To do that,
* we copy JSOPTION_XML from cx->options into cx->version as JSVERSION_HAS_XML
* whenever options are set, and preserve this XML flag across version number
* changes done via the JS_SetVersion API.
*
* But when executing a script or scripted function, the interpreter changes
* cx->version, including the XML flag, to script->version. Thus JSOPTION_XML
* is a compile-time option that causes a run-time version change during each
* activation of the compiled script. That version change has the effect of
* changing JS_HAS_XML_OPTION, so that any compiling done via eval enables XML
* support. If an XML-enabled script or function calls a non-XML function,
* the flag bit will be cleared during the callee's activation.
*
* Note that JS_SetVersion API calls never pass JSVERSION_HAS_XML or'd into
* that API's version parameter.
*
* Note also that script->version must contain this XML option flag in order
* for XDR'ed scripts to serialize and deserialize with that option preserved
* for detection at run-time. We can't copy other compile-time options into
* script->version because that would break backward compatibility (certain
* other options, e.g. JSOPTION_VAROBJFIX, are analogous to JSOPTION_XML).
*/
#define JS_HAS_OPTION(cx,option) (((cx)->options & (option)) != 0)
#define JS_HAS_STRICT_OPTION(cx) JS_HAS_OPTION(cx, JSOPTION_STRICT)
#define JS_HAS_WERROR_OPTION(cx) JS_HAS_OPTION(cx, JSOPTION_WERROR)
#define JS_HAS_COMPILE_N_GO_OPTION(cx) JS_HAS_OPTION(cx, JSOPTION_COMPILE_N_GO)
#define JS_HAS_ATLINE_OPTION(cx) JS_HAS_OPTION(cx, JSOPTION_ATLINE)
#define JSVERSION_MASK 0x0FFF /* see JSVersion in jspubtd.h */
#define JSVERSION_HAS_XML 0x1000 /* flag induced by XML option */
#define JSVERSION_ANONFUNFIX 0x2000 /* see jsapi.h, the comments
for JSOPTION_ANONFUNFIX */
#define JSVERSION_NUMBER(cx) ((JSVersion)((cx)->version & \
JSVERSION_MASK))
#define JS_HAS_XML_OPTION(cx) ((cx)->version & JSVERSION_HAS_XML || \
JSVERSION_NUMBER(cx) >= JSVERSION_1_6)
extern JSThreadData *
js_CurrentThreadData(JSRuntime *rt);
extern JSBool
js_InitThreads(JSRuntime *rt);
extern void
js_FinishThreads(JSRuntime *rt);
extern void
js_PurgeThreads(JSContext *cx);
namespace js {
#ifdef JS_THREADSAFE
/* Iterator over JSThreadData from all JSThread instances. */
class ThreadDataIter : public JSThread::Map::Range
{
public:
ThreadDataIter(JSRuntime *rt) : JSThread::Map::Range(rt->threads.all()) {}
JSThreadData *threadData() const {
return &front().value->data;
}
};
#else /* !JS_THREADSAFE */
class ThreadDataIter
{
JSRuntime *runtime;
bool done;
public:
ThreadDataIter(JSRuntime *rt) : runtime(rt), done(false) {}
bool empty() const {
return done;
}
void popFront() {
JS_ASSERT(!done);
done = true;
}
JSThreadData *threadData() const {
JS_ASSERT(!done);
return &runtime->threadData;
}
};
#endif /* !JS_THREADSAFE */
} /* namespace js */
/*
* Ensures the JSOPTION_XML and JSOPTION_ANONFUNFIX bits of cx->options are
* reflected in cx->version, since each bit must travel with a script that has
* it set.
*/
extern void
js_SyncOptionsToVersion(JSContext *cx);
/*
* Common subroutine of JS_SetVersion and js_SetVersion, to update per-context
* data that depends on version.
*/
extern void
js_OnVersionChange(JSContext *cx);
/*
* Unlike the JS_SetVersion API, this function stores JSVERSION_HAS_XML and
* any future non-version-number flags induced by compiler options.
*/
extern void
js_SetVersion(JSContext *cx, JSVersion version);
/*
* Create and destroy functions for JSContext, which is manually allocated
* and exclusively owned.
*/
extern JSContext *
js_NewContext(JSRuntime *rt, size_t stackChunkSize);
extern void
js_DestroyContext(JSContext *cx, JSDestroyContextMode mode);
/*
* Return true if cx points to a context in rt->contextList, else return false.
* NB: the caller (see jslock.c:ClaimTitle) must hold rt->gcLock.
*/
extern JSBool
js_ValidContextPointer(JSRuntime *rt, JSContext *cx);
static JS_INLINE JSContext *
js_ContextFromLinkField(JSCList *link)
{
JS_ASSERT(link);
return (JSContext *) ((uint8 *) link - offsetof(JSContext, link));
}
/*
* If unlocked, acquire and release rt->gcLock around *iterp update; otherwise
* the caller must be holding rt->gcLock.
*/
extern JSContext *
js_ContextIterator(JSRuntime *rt, JSBool unlocked, JSContext **iterp);
/*
* Iterate through contexts with active requests. The caller must be holding
* rt->gcLock in case of a thread-safe build, or otherwise guarantee that the
* context list is not alternated asynchroniously.
*/
extern JS_FRIEND_API(JSContext *)
js_NextActiveContext(JSRuntime *, JSContext *);
/*
* JSClass.resolve and watchpoint recursion damping machinery.
*/
extern JSBool
js_StartResolving(JSContext *cx, JSResolvingKey *key, uint32 flag,
JSResolvingEntry **entryp);
extern void
js_StopResolving(JSContext *cx, JSResolvingKey *key, uint32 flag,
JSResolvingEntry *entry, uint32 generation);
/*
* Report an exception, which is currently realized as a printf-style format
* string and its arguments.
*/
typedef enum JSErrNum {
#define MSG_DEF(name, number, count, exception, format) \
name = number,
#include "js.msg"
#undef MSG_DEF
JSErr_Limit
} JSErrNum;
extern JS_FRIEND_API(const JSErrorFormatString *)
js_GetErrorMessage(void *userRef, const char *locale, const uintN errorNumber);
#ifdef va_start
extern JSBool
js_ReportErrorVA(JSContext *cx, uintN flags, const char *format, va_list ap);
extern JSBool
js_ReportErrorNumberVA(JSContext *cx, uintN flags, JSErrorCallback callback,
void *userRef, const uintN errorNumber,
JSBool charArgs, va_list ap);
extern JSBool
js_ExpandErrorArguments(JSContext *cx, JSErrorCallback callback,
void *userRef, const uintN errorNumber,
char **message, JSErrorReport *reportp,
bool charArgs, va_list ap);
#endif
extern void
js_ReportOutOfMemory(JSContext *cx);
/*
* Report that cx->scriptStackQuota is exhausted.
*/
void
js_ReportOutOfScriptQuota(JSContext *cx);
extern void
js_ReportOverRecursed(JSContext *cx);
extern void
js_ReportAllocationOverflow(JSContext *cx);
#define JS_CHECK_RECURSION(cx, onerror) \
JS_BEGIN_MACRO \
int stackDummy_; \
\
if (!JS_CHECK_STACK_SIZE(cx, stackDummy_)) { \
js_ReportOverRecursed(cx); \
onerror; \
} \
JS_END_MACRO
/*
* Report an exception using a previously composed JSErrorReport.
* XXXbe remove from "friend" API
*/
extern JS_FRIEND_API(void)
js_ReportErrorAgain(JSContext *cx, const char *message, JSErrorReport *report);
extern void
js_ReportIsNotDefined(JSContext *cx, const char *name);
/*
* Report an attempt to access the property of a null or undefined value (v).
*/
extern JSBool
js_ReportIsNullOrUndefined(JSContext *cx, intN spindex, jsval v,
JSString *fallback);
extern void
js_ReportMissingArg(JSContext *cx, jsval *vp, uintN arg);
/*
* Report error using js_DecompileValueGenerator(cx, spindex, v, fallback) as
* the first argument for the error message. If the error message has less
* then 3 arguments, use null for arg1 or arg2.
*/
extern JSBool
js_ReportValueErrorFlags(JSContext *cx, uintN flags, const uintN errorNumber,
intN spindex, jsval v, JSString *fallback,
const char *arg1, const char *arg2);
#define js_ReportValueError(cx,errorNumber,spindex,v,fallback) \
((void)js_ReportValueErrorFlags(cx, JSREPORT_ERROR, errorNumber, \
spindex, v, fallback, NULL, NULL))
#define js_ReportValueError2(cx,errorNumber,spindex,v,fallback,arg1) \
((void)js_ReportValueErrorFlags(cx, JSREPORT_ERROR, errorNumber, \
spindex, v, fallback, arg1, NULL))
#define js_ReportValueError3(cx,errorNumber,spindex,v,fallback,arg1,arg2) \
((void)js_ReportValueErrorFlags(cx, JSREPORT_ERROR, errorNumber, \
spindex, v, fallback, arg1, arg2))
extern JSErrorFormatString js_ErrorFormatString[JSErr_Limit];
/*
* See JS_SetThreadStackLimit in jsapi.c, where we check that the stack
* grows in the expected direction.
*/
#if JS_STACK_GROWTH_DIRECTION > 0
# define JS_CHECK_STACK_SIZE(cx, lval) ((jsuword)&(lval) < (cx)->stackLimit)
#else
# define JS_CHECK_STACK_SIZE(cx, lval) ((jsuword)&(lval) > (cx)->stackLimit)
#endif
/*
* If the operation callback flag was set, call the operation callback.
* This macro can run the full GC. Return true if it is OK to continue and
* false otherwise.
*/
#define JS_CHECK_OPERATION_LIMIT(cx) \
(!(cx)->operationCallbackFlag || js_InvokeOperationCallback(cx))
/*
* Invoke the operation callback and return false if the current execution
* is to be terminated.
*/
extern JSBool
js_InvokeOperationCallback(JSContext *cx);
#ifndef JS_THREADSAFE
# define js_TriggerAllOperationCallbacks(rt, gcLocked) \
js_TriggerAllOperationCallbacks (rt)
#endif
void
js_TriggerAllOperationCallbacks(JSRuntime *rt, JSBool gcLocked);
extern JSStackFrame *
js_GetScriptedCaller(JSContext *cx, JSStackFrame *fp);
extern jsbytecode*
js_GetCurrentBytecodePC(JSContext* cx);
extern bool
js_CurrentPCIsInImacro(JSContext *cx);
namespace js {
#ifdef JS_TRACER
/*
* Reconstruct the JS stack and clear cx->tracecx. We must be currently in a
* _FAIL builtin from trace on cx or another context on the same thread. The
* machine code for the trace remains on the C stack when js_DeepBail returns.
*
* Implemented in jstracer.cpp.
*/
JS_FORCES_STACK JS_FRIEND_API(void)
DeepBail(JSContext *cx);
#endif
static JS_FORCES_STACK JS_INLINE void
LeaveTrace(JSContext *cx)
{
#ifdef JS_TRACER
if (JS_ON_TRACE(cx))
DeepBail(cx);
#endif
}
static JS_INLINE void
LeaveTraceIfGlobalObject(JSContext *cx, JSObject *obj)
{
if (!obj->fslots[JSSLOT_PARENT])
LeaveTrace(cx);
}
static JS_INLINE JSBool
CanLeaveTrace(JSContext *cx)
{
JS_ASSERT(JS_ON_TRACE(cx));
#ifdef JS_TRACER
return cx->bailExit != NULL;
#else
return JS_FALSE;
#endif
}
} /* namespace js */
/*
* Get the current cx->fp, first lazily instantiating stack frames if needed.
* (Do not access cx->fp directly except in JS_REQUIRES_STACK code.)
*
* Defined in jstracer.cpp if JS_TRACER is defined.
*/
static JS_FORCES_STACK JS_INLINE JSStackFrame *
js_GetTopStackFrame(JSContext *cx)
{
js::LeaveTrace(cx);
return cx->fp;
}
static JS_INLINE JSBool
js_IsPropertyCacheDisabled(JSContext *cx)
{
return cx->runtime->shapeGen >= js::SHAPE_OVERFLOW_BIT;
}
static JS_INLINE uint32
js_RegenerateShapeForGC(JSContext *cx)
{
JS_ASSERT(cx->runtime->gcRunning);
JS_ASSERT(cx->runtime->gcRegenShapes);
/*
* Under the GC, compared with js_GenerateShape, we don't need to use
* atomic increments but we still must make sure that after an overflow
* the shape stays such.
*/
uint32 shape = cx->runtime->shapeGen;
shape = (shape + 1) | (shape & js::SHAPE_OVERFLOW_BIT);
cx->runtime->shapeGen = shape;
return shape;
}
namespace js {
inline void *
ContextAllocPolicy::malloc(size_t bytes)
{
return cx->malloc(bytes);
}
inline void
ContextAllocPolicy::free(void *p)
{
cx->free(p);
}
inline void *
ContextAllocPolicy::realloc(void *p, size_t bytes)
{
return cx->realloc(p, bytes);
}
inline void
ContextAllocPolicy::reportAllocOverflow() const
{
js_ReportAllocationOverflow(cx);
}
class AutoValueVector : private AutoGCRooter
{
public:
explicit AutoValueVector(JSContext *cx
JS_GUARD_OBJECT_NOTIFIER_PARAM)
: AutoGCRooter(cx, VECTOR), vector(cx)
{
JS_GUARD_OBJECT_NOTIFIER_INIT;
}
size_t length() const { return vector.length(); }
bool append(jsval v) { return vector.append(v); }
bool append(JSString *str) { return append(STRING_TO_JSVAL(str)); }
bool append(JSObject *obj) { return append(OBJECT_TO_JSVAL(obj)); }
bool append(jsdouble *dp) { return append(DOUBLE_TO_JSVAL(dp)); }
void popBack() { vector.popBack(); }
bool resize(size_t newLength) {
return vector.resize(newLength);
}
bool reserve(size_t newLength) {
return vector.reserve(newLength);
}
jsval &operator[](size_t i) { return vector[i]; }
jsval operator[](size_t i) const { return vector[i]; }
const jsval *begin() const { return vector.begin(); }
jsval *begin() { return vector.begin(); }
const jsval *end() const { return vector.end(); }
jsval *end() { return vector.end(); }
jsval back() const { return end()[-1]; }
friend void AutoGCRooter::trace(JSTracer *trc);
private:
Vector<jsval, 8> vector;
JS_DECL_USE_GUARD_OBJECT_NOTIFIER
};
JSIdArray *
NewIdArray(JSContext *cx, jsint length);
}
#ifdef _MSC_VER
#pragma warning(pop)
#pragma warning(pop)
#endif
#ifdef JS_UNDEFD_MOZALLOC_WRAPPERS
# include "mozilla/mozalloc_macro_wrappers.h"
#endif
#endif /* jscntxt_h___ */
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