Conditional compare immediate (CCMP_IMM/CCMN_IMM: imm5 at 20:16 via a new
IMM5_HI encoding, bit 11 set), HINT #imm7, MSR <pstatefield>,#imm (new
MSR_PSTATE encoding placing op1 at 18:16 / op2 at 7:5, CRm via the shared
BARRIER_FIELD), and USDOT (I8MM unsigned-by-signed dot product, .2S/.4S).
Hand-written into the core (outside the specgen region). All forms
byte-exact vs llvm-mc and decode-clean; 461 tests green.