corysanin/tubestation
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Bug 657665 - Add documentation comments to ArgumentsObject detailing its structure, and add ArgumentsObject::getElement{,s} to abstract attempting to speedily get the value of one or more elements. r=bhackett

Browse Source
This commit is contained in:
Jeff Walden
2011-05-18 11:45:27 -07:00
parent a9a873263a
commit 30ae04d328
6 changed files with 290 additions and 66 deletions
Download Patch File Download Diff File Expand all files Collapse all files

48
js/src/jsarray.cpp
View File

@@ -357,16 +357,9 @@ GetElement(JSContext *cx, JSObject *obj, jsdouble index, JSBool *hole, Value *vp
return JS_TRUE;
}
if (obj->isArguments()) {
ArgumentsObject *argsobj = obj->asArguments();
if (index < argsobj->initialLength() &&
!(*vp = argsobj->element(uint32(index))).isMagic(JS_ARGS_HOLE)) {
if (obj->asArguments()->getElement(uint32(index), vp)) {
*hole = JS_FALSE;
StackFrame *fp = reinterpret_cast<StackFrame *>(argsobj->getPrivate());
if (fp != JS_ARGUMENTS_OBJECT_ON_TRACE) {
if (fp)
*vp = fp->canonicalActualArg(index);
return JS_TRUE;
}
return true;
}
}
@@ -397,19 +390,6 @@ GetElement(JSContext *cx, JSObject *obj, jsdouble index, JSBool *hole, Value *vp
namespace js {
struct STATIC_SKIP_INFERENCE CopyNonHoleArgsTo
{
CopyNonHoleArgsTo(ArgumentsObject *argsobj, Value *dst) : argsobj(argsobj), dst(dst) {}
ArgumentsObject *argsobj;
Value *dst;
bool operator()(uintN argi, Value *src) {
if (argsobj->element(argi).isMagic(JS_ARGS_HOLE))
return false;
*dst++ = *src;
return true;
}
};
static bool
GetElementsSlow(JSContext *cx, JSObject *aobj, uint32 length, Value *vp)
{
@@ -436,29 +416,9 @@ GetElements(JSContext *cx, JSObject *aobj, jsuint length, Value *vp)
if (aobj->isArguments()) {
ArgumentsObject *argsobj = aobj->asArguments();
if (!argsobj->hasOverriddenLength() && !js_PrototypeHasIndexedProperties(cx, argsobj)) {
/*
* If the argsobj is for an active call, then the elements are the
* live args on the stack. Otherwise, the elements are the args that
* were copied into the argsobj by PutActivationObjects when the
* function returned. In both cases, it is necessary to fall off the
* fast path for deleted properties (MagicValue(JS_ARGS_HOLE) since
* this requires general-purpose property lookup.
*/
if (StackFrame *fp = reinterpret_cast<StackFrame *>(argsobj->getPrivate())) {
JS_ASSERT(fp->numActualArgs() <= JS_ARGS_LENGTH_MAX);
if (fp->forEachCanonicalActualArg(CopyNonHoleArgsTo(argsobj, vp)))
return true;
} else {
Value *srcbeg = argsobj->elements();
Value *srcend = srcbeg + length;
for (Value *dst = vp, *src = srcbeg; src < srcend; ++dst, ++src) {
if (src->isMagic(JS_ARGS_HOLE))
return GetElementsSlow(cx, argsobj, length, vp);
*dst = *src;
}
if (!argsobj->hasOverriddenLength()) {
if (argsobj->getElements(0, length, vp))
return true;
}
}
}