The ObjectFile plugin interface accepts an optional DataBufferSP
argument. If the caller has the contents of the binary, it can provide
this in that DataBufferSP. The ObjectFile subclasses in their
CreateInstance methods will fill in the DataBufferSP with the actual
binary contents if it is not set.
ObjectFile base class creates an ivar DataExtractor from the
DataBufferSP passed in.
My next patch will be a caller that creates a VirtualDataExtractor with
the binary data, and needs to pass that in to the ObjectFile plugin,
instead of the bag-of-bytes DataBufferSP. It builds on the previous
patch changing ObjectFile's ivar from DataExtractor to DataExtractorSP
so I could pass in a subclass in the shared ptr. And it will be using
the VirtualDataExtractor that Jonas added in
https://github.com/llvm/llvm-project/pull/168802
No behavior is changed by the patch; we're simply moving the creation of
the DataExtractor to the caller, instead of a DataBuffer that is
immediately used to set up the ObjectFile DataExtractor. The patch is a
bit complicated because all of the ObjectFile subclasses have to
initialize their DataExtractor to pass in to the base class.
I ran the testsuite on macOS and on AArch64 Ubutnu. (btw David, I ran it
under qemu on my M4 mac with SME-no-SVE again, Ubuntu 25.10, checked
lshw(1) cpu capabilities, and qemu doesn't seem to be virtualizing the
SME, that explains why the testsuite passes)
rdar://148939795
---------
Co-authored-by: Jonas Devlieghere <jonas@devlieghere.com>
ObjectFile has an m_data DataExtractor ivar which may be default
constructed initially, or initialized with a DataBuffer passed in to its
ctor. If the DataExtractor does not get a DataBuffer source passed in,
the subclass will initialize it with access to the object file's data.
When a DataBuffer is passed in to the base class ctor, the DataExtractor
only has its buffer initialized; ObjectFile doesn't yet know the address
size and endianness to fully initialize the DataExtractor.
This patch changes ObjectFile to instead have a DataExtractorSP ivar
which is always initialized with at least a default-constructed
DataExtractor object in the base class ctor. The next patch I will be
writing is to change the ObjectFile ctor to take an optional
DataExtractorSP, so the caller can pass a DataExtractor subclass -- the
VirtualizeDataExtractor being added via
https://github.com/llvm/llvm-project/pull/168802
instead of a DataBuffer which is trivially saved into the DataExtractor.
The change is otherwise mechanical; all `m_data.` changed to
`m_data_sp->` and all the places where `m_data` was passed in for a
by-ref call were changed to `*m_data_sp.get()`. The shared pointer is
always initialized to contain an object.
I built & ran the testsuite on macOS and on aarch64-Ubuntu (thanks for
getting the Linux testsuite to run on SME-only systems David). All of
the ObjectFile subclasses I modifed compile cleanly, but I haven't
tested them beyond any unit tests they may have (prob breakpad).
rdar://148939795
