As the extern_weak target might be missing, resolving to the absolute
address zero, we can't use the normal direct PC-relative branch
instructions (as that would result in relocations out of range).
Instead check the shouldAssumeDSOLocal method and load the address
from a COFF stub.
This matches what was done for X86 in 6bf108d77a.
Differential Revision: https://reviews.llvm.org/D71720
I'm really not sure why we were in the first place, it's the linker's job to
convert between BL/BLX as necessary. Even worse, using BLX left Thumb calls
that could be locally resolved completely unencodable since all offsets to BLX
are multiples of 4.
rdar://26182344
llvm-svn: 269101
Weak externals are resolved statically, so we can actually generate the tail
call on PE/COFF targets without breaking the requirements. It is questionable
whether we want to propagate the current behaviour for MachO as the requirements
are part of the ARM ELF specifications, and it seems that prior to the SVN
r215890, we would have tail'ed the call. For now, be conservative and only
permit it on PE/COFF where the call will always be fully resolved.
llvm-svn: 225119