SSATmp* TraceBuilder::preOptimizeStLoc(IRInstruction* inst) {
auto locId = inst->extra<StLoc>()->locId;
auto const curType = localType(locId, DataTypeGeneric);
auto const newType = inst->src(1)->type();
assert(inst->typeParam().equals(Type::None));
// There's no need to store the type if it's going to be the same
// KindOfFoo. We still have to store string types because we don't
// guard on KindOfStaticString vs. KindOfString.
auto const bothBoxed = curType.isBoxed() && newType.isBoxed();
auto const sameUnboxed = curType != Type::None && // TODO(#2135185)
curType.isSameKindOf(newType) &&
!curType.isString();
if (bothBoxed || sameUnboxed) {
// TODO(t2598894) once relaxGuards supports proper type reflowing, we
// should be able to relax the constraint here and degrade StLocNT to
// StLoc if we relax its input.
if (sameUnboxed) constrainLocal(locId, DataTypeSpecific,
"StLoc -> StLocNT");
inst->setOpcode(StLocNT);
}
return nullptr;
}
SSATmp* TraceBuilder::preOptimizeStLoc(IRInstruction* inst) {
// Guard relaxation might change the current local type, so don't try to
// change to StLocNT until after relaxation happens.
if (!inReoptimize()) return nullptr;
auto locId = inst->extra<StLoc>()->locId;
auto const curType = localType(locId, DataTypeGeneric);
auto const newType = inst->src(1)->type();
assert(inst->typeParam() == Type::None);
// There's no need to store the type if it's going to be the same
// KindOfFoo. We still have to store string types because we don't
// guard on KindOfStaticString vs. KindOfString.
auto const bothBoxed = curType.isBoxed() && newType.isBoxed();
auto const sameUnboxed =
curType.isSameKindOf(newType) && !curType.isString();
if (bothBoxed || sameUnboxed) {
inst->setOpcode(StLocNT);
}
return nullptr;
}
