* Allow normal function results of @yield_once coroutines
* Address review comments
* Workaround LLVM coroutine codegen problem: it assumes that unwind path never returns.
This is not true to Swift coroutines as unwind path should end with error result.
This adds SIL-level support and LLVM codegen for normal results of a coroutine.
The main user of this will be autodiff as VJP of a coroutine must be a coroutine itself (in order to produce the yielded result) and return a pullback closure as a normal result.
For now only direct results are supported, but this seems to be enough for autodiff purposes.
When determining where to destroy a captured alloc_box, the frontier of
the capturing partial_apply is computed. Previously, that computation
just used the uses of the partial_apply. If the partial_apply were
moved and the original destroyed before the apply, however, the result
would be a miscompile where the destroy_addr/dealloc_stack for the
alloc_stack to which the alloc_box was promoted was destroyed before the
apply of the closure which used the address.
When determining where to destroy a captured alloc_box, the frontier of
the capturing partial_apply is computed. Previously, that computation
just used the uses of the partial_apply. If the partial_apply were
copied and the original destroyed before the apply, however, the result
would be a miscompile where the destroy_addr/dealloc_stack for the
alloc_stack to which the alloc_box was promoted was destroyed before the
apply of the closure which used the address.
In preparation for changing the default, explicitly specify the behavior
of all tests that are affected by the choice of behavior for lexical
lifetimes and copy-propagation.
* Don't always give shared linkage to spl functions
private functions on specialization were being given shared linkage.
Use swift::getSpecializeLinkage to correctly get the linkage for the
specialized function based on the linkage of the original function.
* Extend AllocBoxToStack to handle apply
AllocBoxToStack analyzes the uses of boxes and promotes them to stack if
it is safe to do so. Currently the analysis is limited to only a few known
users including partial_apply.
With this change, the pass also analyzes apply users, where the callee
is a local private function.
The analysis is recursive and bound by a threshold.
Fixes rdar://59070139
