https://github.com/llvm/llvm-project/pull/80683 revealed that
hlfir.as_expr was propagating the temporary buffer for polymorphic
values as an allocatable while codegen later expects to be working with
fir.box/fir.class but not fir.ref<box/class> when processing the
operations using the hlfir.as_expr result.
Dereference the temporary allocatable as soon as it is created.
This set of commits resolves some of the issues with elemental calls producing
results that may require finalization, and also some memory leak issues due to
the missing deallocation of allocatable components of the temporary buffers
created by the bufferization pass.
- [flang][runtime] Expose Finalize API for derived types.
- [flang][hlfir] Add 'finalize' attribute for DestroyOp.
- [flang][hlfir] Postpone result finalization for elemental calls.
The results of elemental calls generated inside hlfir.elemental must not
be finalized/destructed before they are copied into the resulting
array. The finalization must be done on the array as a whole
(e.g. there might be different scalar and array finalization routines).
The finalization work is left to the hlfir.destroy corresponding
to this hlfir.elemental.
- [flang][hlfir] Tighten requirements on hlfir.end_associate operand.
If component deallocation might be required for the operand of
hlfir.end_associate, we have to be able to get the variable
shape/params to create a descriptor for calling the runtime.
This commit adds verification that we can do so.
- [flang][hlfir] Lower argument clean-ups using valid hlfir.end_associate.
The operand must be a Fortran entity, when allocatable component
deallocation may be required.
- [flang][hlfir] Properly clean-up temporary buffers in bufferization pass.
This commit combines changes for proper finalization and component
deallocation of the temporary buffers. The finalization part
relates to hlfir.destroy operations with 'finalize' attribute.
The component deallocation might be invoked for both hlfir.destroy
and hlfir.end_associate, if the operand is of a derived type
with allocatable component(s).
The changes are mostly in one function, so I decided not to split them.
- [flang][hlfir] Disable optimizations for hlfir.elemental requiring finalization.
If hlfir.elemental is coupled with hlfir.destroy with 'finalize' attribute,
the temporary array result of hlfir.elemental needs to be created
for the purpose of finalization. We cannot do certain optimizations
on such hlfir.elemental operations.
I was not able to come up with a test for the OptimizedBufferization pass,
but I put the check there as well.
This patch sets 'polymorphic' attribute of hlfir::ExprType when
the value is created from a polymorphic entity.
Memoization of such ExprType involves creating a mutable descriptor
on the stack, which is initialized (as a null box) and passed to
AllocatableApplyMold with the mold being the entity from which
the ExprType value is being created.
This patch fixes "creating polymorphic temporary" TODO and also
several cases of "'fir.convert' op invalid type conversion" error.
Reviewed By: tblah
Differential Revision: https://reviews.llvm.org/D155541
