target/arm: Convert exception generation instructions to decodetree
Convert the exception generation instructions SVC, HVC, SMC, BRK and
HLT to decodetree.
The old decoder decoded the halting-debug insnns DCPS1, DCPS2 and
DCPS3 just in order to then make them UNDEF; as with DRPS, we don't
bother to decode them, but document the patterns in a64.decode.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id:
20230602155223.
2040685-8-peter.maydell@linaro.org