@------------------------------------------------------------------------------
isb sy
isb
+ isb #15
+ isb #1
@ CHECK: isb sy @ encoding: [0x6f,0xf0,0x7f,0xf5]
@ CHECK: isb sy @ encoding: [0x6f,0xf0,0x7f,0xf5]
+@ CHECK: isb sy @ encoding: [0x6f,0xf0,0x7f,0xf5]
+@ CHECK: isb #0x1 @ encoding: [0x61,0xf0,0x7f,0xf5]
@------------------------------------------------------------------------------