void MInstrEffects::get(const IRInstruction* inst,
const FrameStateMgr& frame,
LocalStateHook& hook) {
// If the base for this instruction is a local address, the helper call might
// have side effects on the local's value
auto const base = inst->src(minstrBaseIdx(inst->op()));
auto const locInstr = base->inst();
// Right now we require that the address of any affected local is the
// immediate source of the base tmp. This isn't actually specified in the ir
// spec right now but will intend to make it more general soon.
if (locInstr->op() != LdLocAddr) return;
auto const locId = locInstr->extra<LdLocAddr>()->locId;
auto const baseType = frame.localType(locId);
MInstrEffects effects(inst->op(), baseType.ptr(Ptr::Frame));
if (effects.baseTypeChanged || effects.baseValChanged) {
auto const ty = effects.baseType.derefIfPtr();
if (ty.isBoxed()) {
hook.setLocalType(locId, Type::BoxedInitCell);
hook.setBoxedLocalPrediction(locId, ty);
} else {
hook.setLocalType(locId, ty);
}
}
}
/**
* This method changes any boxed local into a BoxedInitCell type. It's safe to
* assume they're init because you can never have a reference to uninit.
*/
void FrameState::dropLocalRefsInnerTypes(LocalStateHook& hook) const {
walkAllInlinedLocals(
[&](uint32_t i, unsigned inlineIdx, const LocalState& local) {
if (local.type.isBoxed()) {
hook.dropLocalInnerType(i, inlineIdx);
}
});
}
/**
* Called to clear out the tracked local values at a call site. Calls kill all
* registers, so we don't want to keep locals in registers across calls. We do
* continue tracking the types in locals, however.
*/
void FrameState::killLocalsForCall(LocalStateHook& hook,
bool skipThisFrame) const {
walkAllInlinedLocals(
[&](uint32_t i, unsigned inlineIdx, const LocalState& local) {
auto* value = local.value;
if (!value || value->inst()->is(DefConst)) return;
hook.killLocalForCall(i, inlineIdx, value);
},
skipThisFrame);
}
void FrameState::refineLocalValues(LocalStateHook& hook,
SSATmp* oldVal, SSATmp* newVal) const {
assert(newVal->inst()->is(CheckType));
assert(newVal->inst()->src(0) == oldVal);
for (unsigned i = 0, n = m_locals.size(); i < n; ++i) {
if (m_locals[i].value == oldVal) {
hook.refineLocalValue(i, oldVal, newVal);
}
}
}
//
// This method updates the tracked values and types of all locals that contain
// oldRef so that they now contain newRef.
// This should only be called for ref/boxed types.
//
void FrameState::updateLocalRefValues(LocalStateHook& hook,
SSATmp* oldRef, SSATmp* newRef) const {
assert(oldRef->type().isBoxed());
assert(newRef->type().isBoxed());
walkAllInlinedLocals(
[&](uint32_t i, unsigned inlineIdx, const LocalState& local) {
if (local.value != oldRef) return;
hook.updateLocalRefValue(i, inlineIdx, oldRef, newRef);
});
}
void FrameState::refineLocalValues(LocalStateHook& hook,
SSATmp* oldVal, SSATmp* newVal) const {
assert(newVal->inst()->is(CheckType, AssertType));
assert(newVal->inst()->src(0) == oldVal);
walkAllInlinedLocals(
[&](uint32_t i, unsigned inlineIdx, const LocalState& local) {
if (local.value == oldVal) {
hook.refineLocalValue(i, inlineIdx, oldVal, newVal);
}
});
}
void local_effects(const FrameStateMgr& frameState,
const IRInstruction* inst,
LocalStateHook& hook) {
auto killIterLocals = [&](const std::initializer_list<uint32_t>& ids) {
for (auto id : ids) {
hook.setLocalValue(id, nullptr);
}
};
switch (inst->op()) {
case CallBuiltin:
if (inst->extra<CallBuiltin>()->destroyLocals) hook.clearLocals();
break;
case Call:
case CallArray:
case ContEnter:
{
auto const callDestroysLocals =
(inst->is(CallArray) && inst->extra<CallArray>()->destroyLocals) ||
(inst->is(Call) && inst->extra<Call>()->destroyLocals);
hook.killLocalsForCall(callDestroysLocals);
}
break;
case StRef:
hook.updateLocalRefPredictions(inst->src(0), inst->src(1));
break;
case StLocNT:
case StLoc:
hook.setLocalValue(inst->extra<LocalId>()->locId, inst->src(1));
break;
case LdLoc:
hook.setLocalValue(inst->extra<LdLoc>()->locId, inst->dst());
break;
case StLocPseudoMain:
hook.predictLocalType(inst->extra<LocalId>()->locId,
inst->src(1)->type());
break;
case AssertLoc:
case GuardLoc:
case CheckLoc: {
auto id = inst->extra<LocalId>()->locId;
if (inst->marker().func()->isPseudoMain()) {
hook.predictLocalType(id, inst->typeParam());
} else {
hook.refineLocalType(id,
inst->typeParam(),
TypeSource::makeGuard(inst));
}
break;
}
case HintLocInner:
hook.setBoxedLocalPrediction(inst->extra<HintLocInner>()->locId,
inst->typeParam());
break;
case CheckType:
case AssertType:
hook.refineLocalValues(inst->src(0), inst->dst());
break;
case IterInitK:
case WIterInitK:
// kill the locals to which this instruction stores iter's key and value
killIterLocals({inst->extra<IterData>()->keyId,
inst->extra<IterData>()->valId});
break;
case IterInit:
case WIterInit:
// kill the local to which this instruction stores iter's value
killIterLocals({inst->extra<IterData>()->valId});
break;
case IterNextK:
case WIterNextK:
// kill the locals to which this instruction stores iter's key and value
killIterLocals({inst->extra<IterData>()->keyId,
inst->extra<IterData>()->valId});
break;
case IterNext:
case WIterNext:
// kill the local to which this instruction stores iter's value
killIterLocals({inst->extra<IterData>()->valId});
break;
case InterpOne:
case InterpOneCF: {
auto const& id = *inst->extra<InterpOneData>();
assert(!id.smashesAllLocals || id.nChangedLocals == 0);
if (id.smashesAllLocals || inst->marker().func()->isPseudoMain()) {
hook.clearLocals();
} else {
auto it = id.changedLocals;
auto const end = it + id.nChangedLocals;
for (; it != end; ++it) {
auto& loc = *it;
// If changing the inner type of a boxed local, also drop the
// information about inner types for any other boxed locals.
if (loc.type.isBoxed()) hook.dropLocalRefsInnerTypes();
hook.setLocalType(loc.id, loc.type);
}
}
break;
}
default:
break;
}
if (MInstrEffects::supported(inst)) {
MInstrEffects::get(inst, frameState, hook);
}
}
///// Support helpers for getLocalEffects /////
void FrameState::clearLocals(LocalStateHook& hook) const {
for (unsigned i = 0; i < m_locals.size(); ++i) {
hook.setLocalValue(i, nullptr);
}
}
void FrameState::getLocalEffects(const IRInstruction* inst,
LocalStateHook& hook) const {
auto killIterLocals = [&](const std::initializer_list<uint32_t>& ids) {
for (auto id : ids) {
hook.setLocalValue(id, nullptr);
}
};
auto killedCallLocals = false;
if ((inst->is(CallArray) && inst->extra<CallArrayData>()->destroyLocals) ||
(inst->is(Call, CallBuiltin) && inst->extra<CallData>()->destroyLocals)) {
clearLocals(hook);
killedCallLocals = true;
}
switch (inst->op()) {
case Call:
case CallArray:
case ContEnter:
killLocalsForCall(hook, killedCallLocals);
break;
case StRef: {
SSATmp* newRef = inst->dst();
SSATmp* prevRef = inst->src(0);
// update other tracked locals that also contain prevRef
updateLocalRefValues(hook, prevRef, newRef);
break;
}
case StLocNT:
case StLoc:
hook.setLocalValue(inst->extra<LocalId>()->locId, inst->src(1));
break;
case LdLoc:
hook.setLocalValue(inst->extra<LdLoc>()->locId, inst->dst());
break;
case AssertLoc:
case GuardLoc:
case CheckLoc:
hook.refineLocalType(inst->extra<LocalId>()->locId, inst->typeParam(),
inst->dst());
break;
case CheckType:
case AssertType: {
SSATmp* newVal = inst->dst();
SSATmp* oldVal = inst->src(0);
refineLocalValues(hook, oldVal, newVal);
break;
}
case IterInitK:
case WIterInitK:
// kill the locals to which this instruction stores iter's key and value
killIterLocals({inst->extra<IterData>()->keyId,
inst->extra<IterData>()->valId});
break;
case IterInit:
case WIterInit:
// kill the local to which this instruction stores iter's value
killIterLocals({inst->extra<IterData>()->valId});
break;
case IterNextK:
case WIterNextK:
// kill the locals to which this instruction stores iter's key and value
killIterLocals({inst->extra<IterData>()->keyId,
inst->extra<IterData>()->valId});
break;
case IterNext:
case WIterNext:
// kill the local to which this instruction stores iter's value
killIterLocals({inst->extra<IterData>()->valId});
break;
case InterpOne:
case InterpOneCF: {
auto const& id = *inst->extra<InterpOneData>();
assert(!id.smashesAllLocals || id.nChangedLocals == 0);
if (id.smashesAllLocals) {
clearLocals(hook);
} else {
auto it = id.changedLocals;
auto const end = it + id.nChangedLocals;
for (; it != end; ++it) {
auto& loc = *it;
// If changing the inner type of a boxed local, also drop the
// information about inner types for any other boxed locals.
if (loc.type.isBoxed()) dropLocalRefsInnerTypes(hook);
hook.setLocalType(loc.id, loc.type);
}
}
break;
}
default:
break;
}
if (MInstrEffects::supported(inst)) MInstrEffects::get(inst, hook);
}
