Comparison of instruction sets:
System/360, System/370, 370-XA
1. New instructions introduced in System/370, compared to System/360 Opcode Mnemonic Operation Ref in 370-XA Princs of Op 0D BASR Branch and save register 7-10 0E MVCL Move long 7-27 0F CLCL Compare logical long 7-17 4D BAS Branch and save 7-10 AC STNSM Store then AND system mask 10-44 AD STOSM Store then OR system mask 10-44 AE SIGP Signal processor 10-41 AF MC Monitor call 7-26 B1 LRA Load real address 10-18 B2xx Channel set, Clock, Timer PURGE TLB, PREFIX, Ref bit, PTE instructions, Cross-memory service instructions B6 STCTL Store control 10-42 B7 LCTL Load control 10-17 BA CS Compare and swap 7-14 BB CDS Compare double and swap 7-14 BD CLM Compare logical characters under mask 7-16 BE STCM Store characters under mask 7-38 BF ICM Insert characters under mask 7-23 D9 MVCK Move with key 10-20 DA MVCP Move to primary 10-19 DB MVCS Move to secondary 10-19 E500 LASP Load address space parameters 10-10 E501 TPROT Test protection 10-47 E8 + MVCI Move inverse F0 SRP Shift and round decimal 8-10 The action of the following instruction is modified in System/370 depending on the address mode bit in the PSW: 41 LA Load address. In 24-bit mode, the top byte of the destination register is set to zero. In 31-bit mode, the destination register contains the 31-bit address. Likewise the BAS and BASR instructions also depend on the current address mode. In 24-bit mode they behave exactly as BAL, BALR respectively, but in 31-bit mode the link register is set to contain the 31-bit address. The instruction length code, condition code and program mask provided by BAL, BALR may be obtained instead using the new instruction IPK Insert program mask. THERE IS THEREFORE NO CASE for using BAL, BALR in the future, at least for their branch function (they can still be used to get CC and PM into the top byte of the operand-1 register) since BAS and BASR provide the necessary forward and backward compatibility. Most of the XA instructions are now implemented on the 370-XA simulator on EMAS 2900, apart from those relating to key and PSW manipulation and dual address space. The MVCI instruction marked + is not perpetuated in 370-XA. 2. New instructions for 370-XA 0B BSM Branch and set mode 7-11 0C BASSM Branch and save and set mode 7-11 99 TRACE Trace 10-48 B222 IPK Insert program key 7-23 B22D DXR Divide (extended) 9-8 And the following instructions are withdrawn: 08 SSK Set storage key 09 ISK Insert storage key 84 Write direct 85 Read direct B200-B201 Connect, disconnect channel set B213 Reset reference bit (use extended form) E8 MVCI Move inverse(!) K Yarwood 10/1/84