Summary:
The offloading entries right now are assumed to be baked into the binary
itself, and thus always valid whenever the library is executing. This
means that we don't need to copy them to additional storage and can
instead simply pass around references to it.
This is not likely to change in the expected operation of the OpenMP
library. Additionally, the indirection for the offload entry struct is
simply two pointers, so moving it by value is trivial.
Summary:
This patch reorganizes a lot of the code used to check for compatibility
with the current environment. The main bulk of this patch involves
moving from using a separate `__tgt_image_info` struct (which just
contains a string for the architecture) to instead simply checking this
information from the ELF directly. Checking information in the ELF is
very inexpensive as creating an ELF file is simply writing a base
pointer.
The main desire to do this was to reorganize everything into the ELF
image. We can then do the majority of these checks without first
initializing the plugin. A future patch will move the first ELF checks
to happen without initializing the plugin so we no longer need to
initialize and plugins that don't have needed images.
This patch also adds a lot more sanity checks for whether or not the ELF
is actually compatible. Such as if the images have a valid ABI, 64-bit
width, executable, etc.
This moves the offload entry logic into classes and provides convenient
accessors. No functional change intended but we can now print all
offload entries (and later look them up), tested via
`OMPTARGET_DUMP_OFFLOAD_ENTRIES=<device_no>`.
