The runtime API for copy-in copy-out currently only has an entry only
for the copy-out. This entry has a "skipInit" boolean that is never set
to false by lowering and it does not deal with the deallocation of the
temporary.
The generated code was a mix of inline code and runtime calls This is not a big deal,
but this is unneeded compiler and generated code complexity.
With assumed-rank, it is also more cumbersome to establish a
temporary descriptor.
Instead, this patch:
- Adds a CopyInAssignment API that deals with establishing the temporary
descriptor and does the copy.
- Removes unused arg to CopyOutAssign, and pushes
destruction/deallocation responsibility inside it.
Note that this runtime API are still not responsible for deciding the
need of copying-in and out. This is kept as a separate runtime call to
IsContiguous, which is easier to inline/replace by inline code with the
hope of removing the copy-in/out calls after user function inlining.
@vzakhari has already shown that always inlining all the copy part
increase Fortran compilation time due to loop optimization attempts for
loops that are known to have little optimization profitability (the
variable being copied from and to is not contiguous).
There are several observations regarding the copy-in/copy-out:
* Actual argument associated with INTENT(OUT) dummy argument that
requires finalization (7.5.6.3 p. 7) may be read by the finalization
function, so a copy-in is required.
* A temporary created for the copy-in/copy-out must be destroyed
without finalization after the call (or after the corresponding copy-out),
otherwise, memory leaks may occur.
* The copy-out assignment must not perform finalization for the LHS.
* The copy-out assignment from the temporary to the actual argument
may or may not need to initialize the LHS.
This change-set introduces new runtime methods: CopyOutAssign and
DestroyWithoutFinalization. They are called by the compiler generated
code to match the behavior described above.
Reviewed By: jeanPerier
Differential Revision: https://reviews.llvm.org/D151135
- use AssignExplicitLengthCharacter for assignment to whole allocatable
character with assumed or explicit length.
- use AssignPolymorphic for assignment to whole allocatable
polymorphic.
Differential Revision: https://reviews.llvm.org/D145363
Make use of the new runtime entry point for assignment to
LHS allocatable polymorphic.
Reviewed By: jeanPerier
Differential Revision: https://reviews.llvm.org/D145324
This removes any potential confusion with the `getType` accessors
which correspond to SSA results of an operation, and makes it
clear what the intent is (i.e. to represent the type of the function).
Differential Revision: https://reviews.llvm.org/D121762
This patch adds the builder that generate assignment runtime API calls.
This patch is part of the upstreaming effort from fir-dev branch.
Reviewed By: rovka, awarzynski
Differential Revision: https://reviews.llvm.org/D114475
Co-authored-by: Jean Perier <jperier@nvidia.com>
