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Optimize ComputeGlobalThis (395993, r=mrbkap).

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git-svn-id: svn://10.0.0.236/trunk@245807 18797224-902f-48f8-a5cc-f745e15eee43
This commit is contained in:
brendan%mozilla.org
2008-02-16 02:46:46 +00:00
parent 234b6e7e8b
commit 4aeee9d819
8 changed files with 124 additions and 96 deletions
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4
mozilla/js/src/jsapi.c
View File

@@ -4254,7 +4254,7 @@ js_generic_fast_native_method_dispatcher(JSContext *cx, uintN argc, jsval *vp)
* Follow Function.prototype.apply and .call by using the global object as
* the 'this' param if no args.
*/
if (!js_ComputeThis(cx, vp + 2))
if (!js_ComputeThis(cx, JS_FALSE, vp + 2))
return JS_FALSE;
/*
* Protect against argc underflowing. By calling js_ComputeThis, we made
@@ -4310,7 +4310,7 @@ js_generic_native_method_dispatcher(JSContext *cx, JSObject *obj,
* the 'this' param if no args.
*/
JS_ASSERT(cx->fp->argv == argv);
if (!js_ComputeThis(cx, argv))
if (!js_ComputeThis(cx, JS_TRUE, argv))
return JS_FALSE;
cx->fp->thisp = JSVAL_TO_OBJECT(argv[-1]);

6
mozilla/js/src/jsdbgapi.c
View File

@@ -1087,10 +1087,14 @@ JS_GetFrameCallObject(JSContext *cx, JSStackFrame *fp)
return js_GetCallObject(cx, fp, NULL);
}
JS_PUBLIC_API(JSObject *)
JS_GetFrameThis(JSContext *cx, JSStackFrame *fp)
{
if (!fp->thisp) {
fp->thisp = js_ComputeThis(cx, JS_TRUE, fp->argv);
if (!fp->thisp)
return NULL;
}
return fp->thisp;
}

13
mozilla/js/src/jsemit.c
View File

@@ -2246,7 +2246,7 @@ EmitNameOp(JSContext *cx, JSCodeGenerator *cg, JSParseNode *pn,
if (op == JSOP_ARGUMENTS) {
if (js_Emit1(cx, cg, op) < 0)
return JS_FALSE;
if (callContext && js_Emit1(cx, cg, JSOP_GLOBALTHIS) < 0)
if (callContext && js_Emit1(cx, cg, JSOP_NULL) < 0)
return JS_FALSE;
} else {
if (pn->pn_slot >= 0) {
@@ -5894,16 +5894,11 @@ js_EmitTree(JSContext *cx, JSCodeGenerator *cg, JSParseNode *pn)
/* FALL THROUGH */
default:
/*
* Push the appropriate global object after the expression as the
* |this| parameter for the function call. ECMA-262 specifies that
* this happens after actual argument evaluation, but the result
* can't be affected by argument evaluation so we do it early and
* avoid null testing in js_ComputeThis.
* Push null as a placeholder for the global object, per ECMA-262
* 11.2.3 step 6.
*/
if (!js_EmitTree(cx, cg, pn2) ||
!js_Emit1(cx, cg, JSOP_GLOBALTHIS) < 0) {
if (!js_EmitTree(cx, cg, pn2) || !js_Emit1(cx, cg, JSOP_NULL) < 0)
return JS_FALSE;
}
}
/* Remember start of callable-object bytecode for decompilation hint. */

184
mozilla/js/src/jsinterp.c
View File

@@ -896,8 +896,8 @@ js_GetPrimitiveThis(JSContext *cx, jsval *vp, JSClass *clasp, jsval *thisvp)
*
* The alert should display "true".
*/
static JSBool
ComputeGlobalThis(JSContext *cx, jsval *argv)
static JSObject *
ComputeGlobalThis(JSContext *cx, JSBool lazy, jsval *argv)
{
JSObject *thisp;
JSClass *clasp;
@@ -906,67 +906,94 @@ ComputeGlobalThis(JSContext *cx, jsval *argv)
!OBJ_GET_PARENT(cx, JSVAL_TO_OBJECT(argv[-2]))) {
thisp = cx->globalObject;
} else {
JSStackFrame *fp;
jsid id;
jsval v;
uintN attrs;
JSBool ok;
JSObject *parent;
/* Walk up the parent chain. */
/*
* Walk up the parent chain, first checking that the running script
* has access to the callee's parent object. Note that if lazy, the
* running script whose principals we want to check is the script
* associated with fp->down, not with fp.
*
* FIXME: 417851 -- this access check should not be required, as it
* imposes a performance penalty on all ComputeGlobalThis calls, and
* it represents a maintenance hazard.
*/
fp = cx->fp; /* quell GCC overwarning */
if (lazy) {
JS_ASSERT(!fp->thisp && fp->argv == argv);
fp->dormantNext = cx->dormantFrameChain;
cx->dormantFrameChain = fp;
cx->fp = fp->down;
fp->down = NULL;
}
thisp = JSVAL_TO_OBJECT(argv[-2]);
id = ATOM_TO_JSID(cx->runtime->atomState.parentAtom);
for (;;) {
if (!OBJ_CHECK_ACCESS(cx, thisp, id, JSACC_PARENT, &v, &attrs))
return JS_FALSE;
parent = JSVAL_IS_VOID(v)
? OBJ_GET_PARENT(cx, thisp)
: JSVAL_TO_OBJECT(v);
if (!parent)
break;
thisp = parent;
ok = OBJ_CHECK_ACCESS(cx, thisp, id, JSACC_PARENT, &v, &attrs);
if (lazy) {
cx->dormantFrameChain = fp->dormantNext;
fp->dormantNext = NULL;
fp->down = cx->fp;
cx->fp = fp;
}
if (!ok)
return NULL;
thisp = JSVAL_IS_VOID(v)
? OBJ_GET_PARENT(cx, thisp)
: JSVAL_TO_OBJECT(v);
while ((parent = OBJ_GET_PARENT(cx, thisp)) != NULL)
thisp = parent;
}
clasp = OBJ_GET_CLASS(cx, thisp);
if (clasp->flags & JSCLASS_IS_EXTENDED) {
JSExtendedClass *xclasp = (JSExtendedClass *) clasp;
if (xclasp->outerObject && !(thisp = xclasp->outerObject(cx, thisp)))
return JS_FALSE;
return NULL;
}
argv[-1] = OBJECT_TO_JSVAL(thisp);
return JS_TRUE;
return thisp;
}
static JSBool
ComputeThis(JSContext *cx, jsval *argv)
static JSObject *
ComputeThis(JSContext *cx, JSBool lazy, jsval *argv)
{
JSObject *thisp;
JS_ASSERT(!JSVAL_IS_NULL(argv[-1]));
if (!JSVAL_IS_OBJECT(argv[-1]))
return js_PrimitiveToObject(cx, &argv[-1]);
if (!JSVAL_IS_OBJECT(argv[-1])) {
if (!js_PrimitiveToObject(cx, &argv[-1]))
return NULL;
thisp = JSVAL_TO_OBJECT(argv[-1]);
} else {
thisp = JSVAL_TO_OBJECT(argv[-1]);
if (OBJ_GET_CLASS(cx, thisp) == &js_CallClass)
return ComputeGlobalThis(cx, lazy, argv);
thisp = JSVAL_TO_OBJECT(argv[-1]);
if (OBJ_GET_CLASS(cx, thisp) == &js_CallClass)
return ComputeGlobalThis(cx, argv);
if (!thisp->map->ops->thisObject)
return JS_TRUE;
/* Some objects (e.g., With) delegate 'this' to another object. */
thisp = thisp->map->ops->thisObject(cx, thisp);
if (!thisp)
return JS_FALSE;
argv[-1] = OBJECT_TO_JSVAL(thisp);
return JS_TRUE;
if (thisp->map->ops->thisObject) {
/* Some objects (e.g., With) delegate 'this' to another object. */
thisp = thisp->map->ops->thisObject(cx, thisp);
if (!thisp)
return NULL;
}
argv[-1] = OBJECT_TO_JSVAL(thisp);
}
return thisp;
}
JSBool
js_ComputeThis(JSContext *cx, jsval *argv)
JSObject *
js_ComputeThis(JSContext *cx, JSBool lazy, jsval *argv)
{
if (JSVAL_IS_NULL(argv[-1]))
return ComputeGlobalThis(cx, argv);
return ComputeThis(cx, argv);
return ComputeGlobalThis(cx, lazy, argv);
return ComputeThis(cx, lazy, argv);
}
#if JS_HAS_NO_SUCH_METHOD
@@ -983,9 +1010,9 @@ NoSuchMethod(JSContext *cx, uintN argc, jsval *vp, uint32 flags)
JSBool ok;
jsbytecode *pc;
/* NB: js_ComputeThis or equivalent must have been called already. */
/* NB: vp[1] aka |this| may be null still, requiring ComputeGlobalThis. */
JS_ASSERT(JSVAL_IS_PRIMITIVE(vp[0]));
JS_ASSERT(!JSVAL_IS_PRIMITIVE(vp[1]));
JS_ASSERT(JSVAL_IS_OBJECT(vp[1]));
fp = cx->fp;
RESTORE_SP(fp);
@@ -993,8 +1020,17 @@ NoSuchMethod(JSContext *cx, uintN argc, jsval *vp, uint32 flags)
memset(roots, 0, sizeof roots);
JS_PUSH_TEMP_ROOT(cx, JS_ARRAY_LENGTH(roots), roots, &tvr);
id = ATOM_TO_JSID(cx->runtime->atomState.noSuchMethodAtom);
thisp = JSVAL_TO_OBJECT(vp[1]);
if (!thisp) {
thisp = ComputeGlobalThis(cx, JS_FALSE, vp + 2);
if (!thisp) {
ok = JS_FALSE;
goto out;
}
fp->thisp = thisp;
}
id = ATOM_TO_JSID(cx->runtime->atomState.noSuchMethodAtom);
#if JS_HAS_XML_SUPPORT
if (OBJECT_IS_XML(cx, thisp)) {
JSXMLObjectOps *ops;
@@ -1225,9 +1261,10 @@ have_fun:
* interpreter, where a prior bytecode has computed an appropriate
* |this| already.
*/
ok = js_ComputeThis(cx, vp + 2);
if (!ok)
if (!js_ComputeThis(cx, JS_FALSE, vp + 2)) {
ok = JS_FALSE;
goto out2;
}
}
init_slots:
@@ -3987,6 +4024,14 @@ interrupt:
BEGIN_CASE(JSOP_GETTHISPROP)
i = 0;
obj = fp->thisp;
if (!obj) {
obj = ComputeGlobalThis(cx, JS_TRUE, fp->argv);
if (!obj) {
ok = JS_FALSE;
goto out;
}
fp->thisp = obj;
}
PUSH(JSVAL_NULL);
len = JSOP_GETTHISPROP_LENGTH;
goto do_getprop_with_obj;
@@ -4168,9 +4213,10 @@ interrupt:
goto out;
STORE_OPND(-1, OBJECT_TO_JSVAL(obj));
STORE_OPND(-2, rval);
ok = ComputeThis(cx, sp);
if (!ok)
if (!ComputeThis(cx, JS_FALSE, sp)) {
ok = JS_FALSE;
goto out;
}
} else {
JS_ASSERT(obj->map->ops->getProperty == js_GetProperty);
ok = js_GetPropertyHelper(cx, obj, id, &rval, &entry);
@@ -4500,7 +4546,7 @@ interrupt:
/* Compute the 'this' parameter now that argv is set. */
JS_ASSERT(!JSFUN_BOUND_METHOD_TEST(fun->flags));
JS_ASSERT(!JSVAL_IS_PRIMITIVE(vp[1]));
JS_ASSERT(JSVAL_IS_OBJECT(vp[1]));
newifp->frame.thisp = (JSObject *)vp[1];
/* Push void to initialize local variables. */
@@ -4602,7 +4648,7 @@ interrupt:
SAVE_SP(fp);
}
JS_ASSERT(!JSVAL_IS_PRIMITIVE(vp[1]) ||
JS_ASSERT(JSVAL_IS_OBJECT(vp[1]) ||
PRIMITIVE_THIS_TEST(fun, vp[1]));
ok = ((JSFastNative) fun->u.n.native)(cx, argc, vp);
@@ -4758,9 +4804,10 @@ interrupt:
if (op == JSOP_CALLNAME) {
PUSH_OPND(OBJECT_TO_JSVAL(obj));
SAVE_SP(fp);
ok = ComputeThis(cx, sp);
if (!ok)
if (!ComputeThis(cx, JS_FALSE, sp)) {
ok = JS_FALSE;
goto out;
}
}
}
END_CASE(JSOP_NAME)
@@ -4954,20 +5001,14 @@ interrupt:
BEGIN_CASE(JSOP_THIS)
obj = fp->thisp;
clasp = OBJ_GET_CLASS(cx, obj);
if (clasp->flags & JSCLASS_IS_EXTENDED) {
JSExtendedClass *xclasp;
xclasp = (JSExtendedClass *) clasp;
if (xclasp->outerObject) {
obj = xclasp->outerObject(cx, obj);
if (!obj) {
ok = JS_FALSE;
goto out;
}
if (!obj) {
obj = ComputeGlobalThis(cx, JS_TRUE, fp->argv);
if (!obj) {
ok = JS_FALSE;
goto out;
}
fp->thisp = obj;
}
PUSH_OPND(OBJECT_TO_JSVAL(obj));
END_CASE(JSOP_THIS)
@@ -5227,20 +5268,6 @@ interrupt:
PUSH_OPND(rval);
END_CASE(JSOP_ARGCNT)
#define PUSH_GLOBAL_THIS(cx,sp) \
JS_BEGIN_MACRO \
PUSH_OPND(JSVAL_NULL); \
SAVE_SP_AND_PC(fp); \
ok = ComputeGlobalThis(cx, sp); \
if (!ok) \
goto out; \
JS_ASSERT(!JSVAL_IS_NULL(sp[-1]) && !JSVAL_IS_VOID(sp[-1])); \
JS_END_MACRO
BEGIN_CASE(JSOP_GLOBALTHIS)
PUSH_GLOBAL_THIS(cx, sp);
END_CASE(JSOP_GLOBALTHIS)
BEGIN_CASE(JSOP_GETARG)
BEGIN_CASE(JSOP_CALLARG)
slot = GET_ARGNO(pc);
@@ -5248,7 +5275,7 @@ interrupt:
METER_SLOT_OP(op, slot);
PUSH_OPND(fp->argv[slot]);
if (op == JSOP_CALLARG)
PUSH_GLOBAL_THIS(cx, sp);
PUSH_OPND(JSVAL_NULL);
END_CASE(JSOP_GETARG)
BEGIN_CASE(JSOP_SETARG)
@@ -5267,7 +5294,7 @@ interrupt:
METER_SLOT_OP(op, slot);
PUSH_OPND(fp->vars[slot]);
if (op == JSOP_CALLVAR)
PUSH_GLOBAL_THIS(cx, sp);
PUSH_OPND(JSVAL_NULL);
END_CASE(JSOP_GETVAR)
BEGIN_CASE(JSOP_SETVAR)
@@ -6140,9 +6167,10 @@ interrupt:
if (op == JSOP_CALLXMLNAME) {
PUSH_OPND(OBJECT_TO_JSVAL(obj));
SAVE_SP(fp);
ok = ComputeThis(cx, sp);
if (!ok)
if (!ComputeThis(cx, JS_FALSE, sp)) {
ok = JS_FALSE;
goto out;
}
}
END_CASE(JSOP_XMLNAME)
@@ -6400,7 +6428,7 @@ interrupt:
JS_ASSERT(slot < (uintN)depth);
PUSH_OPND(fp->spbase[slot]);
if (op == JSOP_CALLLOCAL)
PUSH_GLOBAL_THIS(cx, sp);
PUSH_OPND(JSVAL_NULL);
END_CASE(JSOP_GETLOCAL)
BEGIN_CASE(JSOP_SETLOCAL)
@@ -6564,6 +6592,8 @@ interrupt:
L_JSOP_DEFXMLNS:
# endif
L_JSOP_UNUSED117:
#else /* !JS_THREADED_INTERP */
default:
#endif

4
mozilla/js/src/jsinterp.h
View File

@@ -353,8 +353,8 @@ js_GetPrimitiveThis(JSContext *cx, jsval *vp, JSClass *clasp, jsval *thisvp);
* objects as, per ECMA-262, they may not be referred to by |this|. argv[-1]
* must not be a JSVAL_VOID.
*/
extern JSBool
js_ComputeThis(JSContext *cx, jsval *argv);
extern JSObject *
js_ComputeThis(JSContext *cx, JSBool lazy, jsval *argv);
/*
* NB: js_Invoke requires that cx is currently running JS (i.e., that cx->fp

3
mozilla/js/src/jsopcode.c
View File

@@ -2017,7 +2017,6 @@ Decompile(SprintStack *ss, jsbytecode *pc, intN nb, JSOp nextop)
if ((cs->prec != 0 &&
cs->prec <= js_CodeSpec[NEXT_OP(pc)].prec) ||
pc[JSOP_GROUP_LENGTH] == JSOP_NULL ||
pc[JSOP_GROUP_LENGTH] == JSOP_GLOBALTHIS ||
pc[JSOP_GROUP_LENGTH] == JSOP_DUP ||
pc[JSOP_GROUP_LENGTH] == JSOP_IFEQ ||
pc[JSOP_GROUP_LENGTH] == JSOP_IFNE) {
@@ -3770,7 +3769,7 @@ Decompile(SprintStack *ss, jsbytecode *pc, intN nb, JSOp nextop)
* arrange to advance over the call to this lambda.
*/
pc += len;
LOCAL_ASSERT(*pc == JSOP_GLOBALTHIS);
LOCAL_ASSERT(*pc == JSOP_NULL);
pc += JSOP_NULL_LENGTH;
LOCAL_ASSERT(*pc == JSOP_CALL);
LOCAL_ASSERT(GET_ARGC(pc) == 0);

4
mozilla/js/src/jsopcode.tbl
View File

@@ -263,8 +263,8 @@ OPDEF(JSOP_RETSUB, 115,"retsub", NULL, 1, 0, 0, 0, JOF_BYTE)
/* More exception handling ops. */
OPDEF(JSOP_EXCEPTION, 116,"exception", NULL, 1, 0, 1, 0, JOF_BYTE)
/* Push the global object as |this| for a non-reference-type callable. */
OPDEF(JSOP_GLOBALTHIS,117,"globalthis", js_null_str, 1, 0, 1, 0, JOF_BYTE)
/* Unused, formerly JSOP_GLOBALTHIS. */
OPDEF(JSOP_UNUSED117, 117,"unused117", NULL, 1, 0, 0, 0, JOF_BYTE)
/*
* ECMA-compliant switch statement ops.

2
mozilla/js/src/jsxdrapi.h
View File

@@ -202,7 +202,7 @@ JS_XDRFindClassById(JSXDRState *xdr, uint32 id);
* before deserialization of bytecode. If the saved version does not match
* the current version, abort deserialization and invalidate the file.
*/
#define JSXDR_BYTECODE_VERSION (0xb973c0de - 20)
#define JSXDR_BYTECODE_VERSION (0xb973c0de - 21)
/*
* Library-private functions.