Updated the interrupt handling to utilize and report through the target EL
exception field. This includes consolidating and cleaning up code where
needed. Target EL is now calculated once in arm_cpu_exec_interrupt() and
do_interrupt was updated to use the target_el exception field. The
necessary code from arm_excp_target_el() was merged in where needed and the
function removed.
Backports commit 012a906b19e99b126403ff4a257617dab9b34163 from qemu
The AArch64 SPSR_EL1 register is architecturally mandated to
be mapped to the AArch32 SPSR_svc register. This means its
state should live in QEMU's env->banked_spsr[1] field.
Correct the various places in the code that incorrectly
put it in banked_spsr[0].
Backports commit 7847f9ea9fce15a9ecfb62ab72c1e84ff516b0db from qemu
Add AArch32 to AArch64 register sychronization functions.
Replace manual register synchronization with new functions in
aarch64_cpu_do_interrupt() and HELPER(exception_return)().
Backports commit ce02049dbf1828b4bc77d921b108a9d84246e5aa from qemu
The helper functions for FRECPS and FRSQRTS have special case
handling that includes checks for zero inputs, so squash input
denormals if necessary before those checks. This fixes incorrect
output when the FPCR DZ bit is set to enable squashing of input
denormals.
Backports commit a8eb6e19991d1a7a6a7b04ac447548d30d75eb4a from qemu
