Let's revisit these helpers in light of what happens in https://github.com/uliegecsm/kokkos-utils/issues/42.

Member Kokkos::Execution::ExecutionSpaceImpl::Scheduler< Exec >::OpState< Rcvr >::start () &noexcept

Check signature. And check whether we should move the receiver.

Member Kokkos::Execution::GraphImpl::graph_add_node_event (const Predecessor &predecessor, const NodeType &node)

Use https://github.com/kokkos/kokkos/pull/9170 to determine if the predecessor is a root node.

Struct Kokkos::Execution::GraphImpl::GraphAddNodeEvent

Store a label.

Store the dispatch tag.

Member Kokkos::Execution::GraphImpl::Scheduler< Exec >::OpState< Rcvr >::start () &noexcept

Check signature. And check whether we should move the receiver.

Member Kokkos::Execution::Impl::CompletionSignal< SyncPolicy::PassThrough, Exec, Rcvr >::propagate (stdexec::set_value_t) &noexcept

Elaborate this overload, which is currently used by the graph customization.

Member Kokkos::Execution::Impl::RequiresSync< Exec, Rcvr >::operator() (const Exec &exec, const Rcvr &rcvr) const noexcept

Simplify by moving and using Tests::Utils::are_same_instances.

Member Kokkos::Execution::Impl::RequiresSync< Exec, Rcvr >::operator() (const Exec &, const Rcvr &) const noexcept

This is compile-time only and should go away.

Class Tests::ExecutionSpaceImpl::WhenAllTest_nested_with_inner_followed_by_other_Test

There is a missing fence. Our stdexec::continues_on puts the execution space instance in the environment because its preceding stdexec::when_all has at least one branch on Kokkos::Execution::ExecutionSpaceContext.