(1) object code can be shared (where the hardware makes that possible), and
(2) so that the file names better describe the systems which use them. (the
pci_swiz* files are for machines whose PCI interfaces require address
"swizzling." Later, there will be probably be other sets, e.g. pci_bwx*
for machines whose chipsets can easily deal with the Alpha BWX extensions
when doing device accesses.)
This can be disabled (to save a bit of space) with the NO_KERNEL_RCSIDS
options, which is present but commented out in the ALPHA config file.
In ELF-format kernels, these strings are present in the kernel binary but
are not loaded into memory. (In ECOFF-format kernels, there's no easy way
to keep them from being loaded, so they _are_ loaded into memory.)
the same things, but the extent maps have to be managed differently,
since the two chipsets provide different memory and I/O region mapping
possibilities.