In a message dated 9/12/2005 9:47:16 A.M. Central Daylight Time, [EMAIL PROTECTED] writes:
>We simulate new instructions all the time using library macros. This >allows the program to use the instruction as if the HLASM support was >there. Once the instruction is implemented in the assembler, the library >macro is no longer needed. And there are some machine instructions for which op codes will apparently never be provided. E.g., the technical pub titled S/370 Extensions (or something like that) in the early 1980s described some instructions in which certain frequently executed MVS functions, like adding/deleting an FRR, were implemented as single instructions in order to enhance the MVS supervisor performance. These were described in that book with hex constants rather than op codes, and I don't believe IBM has ever granted these instructions the legitimacy of an op code. And then there are some proprietary instructions, documentation for which is available at ca. $10K per photocopied page. These may or may not have op codes, but they will never be documented in the Principles of Operations and they may or may not have Assembler-supported op codes. Bill Fairchild ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
