Older Arm architectures do not support the MOVT and MOVW instructions so we
must use an alternative sequence of instructions to transfer control to the
destination.
Assuming at least Armv5 this patch adds support for Thunks that load or add
to the program counter. Note that there are no Armv5 Thumb Thunks as there
is no Thumb branch instruction in Armv5 that supports Thunks. These thunks
will not work for Armv4t (arm7tdmi) as this architecture cannot change state
from using the LDR or ADD instruction.
Differential Revision: https://reviews.llvm.org/D50077
llvm-svn: 340160
This is what InputSectionBase<ELFT>::relocate does and we need to be
consistent. The other option would be to be more explicit about which
relocations are signed and which are not, and sign extend only when
appropriated. That would require extending the target interface.
llvm-svn: 280366
Peter Smith