# RUN: llvm-mc --disassemble %s -triple=thumb-apple-darwin9 2>&1 | grep "invalid instruction encoding"

# Opcode=2137 Name=t2STR_POST Format=ARM_FORMAT_THUMBFRM(25)
#  31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10  9  8  7  6  5  4  3  2  1  0
# -------------------------------------------------------------------------------------------------
# | 1: 1: 1: 1| 1: 0: 0: 0| 0: 1: 0: 0| 1: 1: 1: 1| 1: 1: 1: 0| 1: 0: 1: 1| 1: 1: 1: 1| 1: 1: 1: 1|
# -------------------------------------------------------------------------------------------------
#
# if Rn == '1111' then UNDEFINED
0x4f 0xf8 0xff 0xeb