void
BaselineFrame::trace(JSTracer *trc, IonFrameIterator &frameIterator)
{
replaceCalleeToken(MarkCalleeToken(trc, calleeToken()));
gc::MarkValueRoot(trc, &thisValue(), "baseline-this");
// Mark actual and formal args.
if (isNonEvalFunctionFrame()) {
unsigned numArgs = js::Max(numActualArgs(), numFormalArgs());
gc::MarkValueRootRange(trc, numArgs, argv(), "baseline-args");
}
// Mark scope chain, if it exists.
if (scopeChain_)
gc::MarkObjectRoot(trc, &scopeChain_, "baseline-scopechain");
// Mark return value.
if (hasReturnValue())
gc::MarkValueRoot(trc, returnValue().address(), "baseline-rval");
if (isEvalFrame())
gc::MarkScriptRoot(trc, &evalScript_, "baseline-evalscript");
if (hasArgsObj())
gc::MarkObjectRoot(trc, &argsObj_, "baseline-args-obj");
// Mark locals and stack values.
JSScript *script = this->script();
size_t nfixed = script->nfixed();
size_t nlivefixed = script->nfixedvars();
if (nfixed != nlivefixed) {
jsbytecode *pc;
NestedScopeObject *staticScope;
frameIterator.baselineScriptAndPc(nullptr, &pc);
staticScope = script->getStaticScope(pc);
while (staticScope && !staticScope->is<StaticBlockObject>())
staticScope = staticScope->enclosingNestedScope();
if (staticScope) {
StaticBlockObject &blockObj = staticScope->as<StaticBlockObject>();
nlivefixed = blockObj.localOffset() + blockObj.numVariables();
}
}
JS_ASSERT(nlivefixed <= nfixed);
JS_ASSERT(nlivefixed >= script->nfixedvars());
// NB: It is possible that numValueSlots() could be zero, even if nfixed is
// nonzero. This is the case if the function has an early stack check.
if (numValueSlots() == 0)
return;
JS_ASSERT(nfixed <= numValueSlots());
if (nfixed == nlivefixed) {
// All locals are live.
MarkLocals(this, trc, 0, numValueSlots());
} else {
// Mark operand stack.
MarkLocals(this, trc, nfixed, numValueSlots());
// Clear dead locals.
while (nfixed > nlivefixed)
unaliasedLocal(--nfixed, DONT_CHECK_ALIASING).setUndefined();
// Mark live locals.
MarkLocals(this, trc, 0, nlivefixed);
}
}
