SS : Skip if Sign bit is set

Skip the next half-words if the source register's MSB (in SRC1) is set (the 2-complement value is negative).

A 2-bit field located in SRC2 contains the Skip Length, which is incremented to fit a value between 1 and 4 half-words, beginning after the skip instruction.

The Imm16 field is not used because the negation field already provides with a XOR.

This is one of the instructions of the SKIP group, see also : SKIP, SZ/SNZ, SO/SNE/SNO/SE, SNS.