Many components under stand/ had CLANG_NO_IAS added when Clang's
Integrated Assembler (IAS) did not handle .codeNN directives. Clang
gained support quite some time ago, and we can now build stand/ with
IAS. In most cases IAS- and GNU as-assembled boot components were
identical, and CLANG_NO_IAS was already removed from other components.
Clang IAS produces different output for some components, including
pxeldr, so CLANG_NO_IAS was not previously removed for those.
In the case of pxeldr the difference is that IAS adds a size override
prefix (67h) to three instructions to specify a 32-bit address, even
though the two high bytes are zero and the address fits in 16 bits.
this wastes three bytes per instruction and causes some additional nop
npadding to be required elsewhere in the object, but pxeboot is not
size-constrained so it doesn't matter.
Sponsored by: The FreeBSD Foundation
Create loader_{4th,lua,simp}{,.efi}. All of these are installed by
default. Create LOADER_DEFAULT_INTERP to specify the default
interpreter when no other is specified. LOADER_INTERP is the current
interpreter language building. Turn building of lua on by default to
match 4th. simploader is a simplified loader build w/o any interpreter
language (but with a simple loader). This is the historic behavir you
got with WITHOUT_FORTH. Make a hard link to the default loader. This
has to be a hard link rather than the more desirable soft link because
older zfsboot blocks don't support symlinks.
RelNotes: Yes
Differential Revision: https://reviews.freebsd.org/D16705
