/**
* checkByRef() returns true if the parameter specified by argNum is pass
* by reference, otherwise it returns false. This function may also throw an
* UnknownInputException if the reffiness cannot be determined.
*
* Note that the 'entryArDelta' parameter specifies the delta between sp at
* the beginning of the tracelet and ar.
*/
bool
ActRecState::checkByRef(int argNum, int entryArDelta, RefDeps* refDeps) {
FTRACE(2, "ActRecState: getting reffiness for arg {}, arDelta {}\n",
argNum, entryArDelta);
if (m_arStack.empty()) {
// The ActRec in question was pushed before the beginning of the
// tracelet, so we can make a guess about parameter reffiness and
// record our assumptions about parameter reffiness as tracelet
// guards.
const ActRec* ar = arFromSpOffset((ActRec*)vmsp(), entryArDelta);
Record r;
r.m_state = State::GUESSABLE;
r.m_entryArDelta = entryArDelta;
ar->m_func->validate();
r.m_topFunc = ar->m_func;
m_arStack.push_back(r);
}
Record& r = m_arStack.back();
if (r.m_state == State::UNKNOWABLE) {
TRACE(2, "ActRecState: unknowable, throwing in the towel\n");
throwUnknownInput();
not_reached();
}
assertx(r.m_topFunc);
bool retval = r.m_topFunc->byRef(argNum);
if (r.m_state == State::GUESSABLE) {
assertx(r.m_entryArDelta != InvalidEntryArDelta);
TRACE(2, "ActRecState: guessing arg%d -> %d\n", argNum, retval);
refDeps->addDep(r.m_entryArDelta, argNum, retval);
}
return retval;
}
/**
* checkByRef() returns true if the parameter specified by argNum is pass
* by reference, otherwise it returns false. This function may also throw an
* UnknownInputException if the reffiness cannot be determined.
*
* Note that the 'entryArDelta' parameter specifies the delta between sp at
* the beginning of the tracelet and ar.
*/
bool
ActRecState::checkByRef(int argNum, int entryArDelta, RefDeps* refDeps,
const RegionContext& ctx) {
FTRACE(2, "ActRecState: getting reffiness for arg {}, arDelta {}\n",
argNum, entryArDelta);
if (m_arStack.empty()) {
// The ActRec in question was pushed before the beginning of the
// tracelet, so we can make a guess about parameter reffiness and
// record our assumptions about parameter reffiness as tracelet
// guards.
auto const func = [&] {
for (auto& ar : ctx.preLiveARs) {
if (ar.stackOff == entryArDelta) return ar.func;
}
not_reached();
}();
Record r;
r.m_state = State::GUESSABLE;
r.m_entryArDelta = entryArDelta;
func->validate();
r.m_topFunc = func;
m_arStack.push_back(r);
}
Record& r = m_arStack.back();
if (r.m_state == State::UNKNOWABLE) {
TRACE(2, "ActRecState: unknowable, throwing in the towel\n");
throwUnknownInput();
not_reached();
}
assertx(r.m_topFunc);
bool retval = r.m_topFunc->byRef(argNum);
if (r.m_state == State::GUESSABLE) {
assertx(r.m_entryArDelta != InvalidEntryArDelta);
TRACE(2, "ActRecState: guessing arg%d -> %d\n", argNum, retval);
refDeps->addDep(r.m_entryArDelta, argNum, retval);
}
return retval;
}