Problem:

A long displacement is a signed 20-bit displacement value, instead of the unsigned 12-bit displacement used with most existing instructions.

There are two groups of long-displacement instructions:

- New instructions. There are 44 of these.

- Existing instructions that are changed to include long displacements. There are 69 of these.

The new instructions are available only when operating in zArchitecture mode.

The modified instructions operate with a long displacement only in zArchitecture mode.

In ESA/390 mode, they operate as they did previously.

Resolution:

The existing instructions modified have a "Y" added to their mnemonics.

Some instructions are AY,AHY,MVIY,NIY,LAY,...,AG, NG, CG, LG, ...

Those new instructions are not supported by the MFE HLL Assembler.

An Enhancement 1060126 has been created to accept them.