Add a fir.llvm_ptr type to allow any level of indirections
Currently, fir pointer types (fir.ref, fir.ptr, and fir.heap) carry
a special Fortran semantics, and cannot be freely combined/nested.
When implementing some features, lowering sometimes needs more liberty
regarding the number of indirection levels. Add a fir.llvm_ptr that has
no constraints.
Allow its usage in fir.coordinate_op, fir.load, and fir.store.
Convert the FIR LLVMPointer to an LLVMPointer in the LLVM dialect.
Reviewed By: clementval
Differential Revision: https://reviews.llvm.org/D113755
Co-authored-by: Jean Perier <jperier@nvidia.com>
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