While working on another issue I found that currently modules do not
work with coroutines at all. This patch fixes a number of issues in
both the coroutines logic and modules logic to ensure that they play
well together. To summarize:
- The coroutine proxy objects did not have a DECL_CONTEXT set (required
for modules to merge declarations).
- The coroutine transformation functions are always non-inline, even
for an inline ramp function, which means that modules need an override
to ensure the definitions are available where needed.
- Coroutine transformation functions were not marked DECL_COROUTINE_P,
despite accessors implying that they were.
- In an importing TU we had lost the connection between the ramp
functions and the transform functions, as they were kept in a pair
of global maps.
- Modules streaming couldn't discriminate between the actor or destroy
functions when merging.
- Modules streaming wasn't setting the cfun->coroutine_component flag,
needed to activate the middle-end coroutine lowering pass.
This patch also separates the coroutine_info_table initialization from
the ensure_coro_initialized function. If the first time we see a
coroutine is from a module import, we need to register the
transformation functions now but calling ensure_coro_initialized would
lookup e.g. std::coroutine_traits, which may only be visible from this
module that we're currently reading, causing a recursive load.
Separating the concerns allows this to work correctly.
gcc/cp/ChangeLog:
* coroutines.cc (create_coroutine_info_table): New function.
(get_or_insert_coroutine_info): Mark static.
(ensure_coro_initialized): Likewise; use
create_coroutine_info_table.
(coro_promise_type_found_p): Set DECL_CONTEXT for proxies.
(coro_set_ramp_function): New function.
(coro_set_transform_functions): New function.
(coro_build_actor_or_destroy_function): Use
coro_set_ramp_function, mark as DECL_COROUTINE_P.
* cp-tree.h (coro_set_transform_functions): Declare.
(coro_set_ramp_function): Declare.
* module.cc (struct merge_key): New field coro_disc.
(dumper::impl::nested_name): Distinguish coroutine transform
functions.
(get_coroutine_discriminator): New function.
(trees_out::key_mergeable): Stream coroutine discriminator.
(check_mergeable_decl): Adjust comment, check for matching
coroutine discriminator.
(trees_in::key_mergeable): Read coroutine discriminator.
(has_definition): Override for coroutine transform functions.
(trees_out::write_function_def): Stream linked ramp, actor, and
destroy functions for coroutines.
(trees_in::read_function_def): Read them.
(module_state::read_cluster): Set cfun->coroutine_component.
gcc/testsuite/ChangeLog:
* g++.dg/modules/coro-1_a.C: New test.
* g++.dg/modules/coro-1_b.C: New test.
Reviewed-by: Iain Sandoe <iain@sandoe.co.uk>
Reviewed-by: Jason Merrill <jason@redhat.com>
Signed-off-by: Nathaniel Shead <nathanieloshead@gmail.com>
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