under which it is executing supports the VM/VS Handshaking feature. If the
extended-identification code is returned to VS 1, VM/SP supports handshaking;
otherwise, it does not.
Entry Values: The register specified as Rx contains the doubleword aligned virtual
storage address where the VM/SP extended-identification code is to be stored.
The Ry register contains the number of bytes to be stored entered as an unsigned
binary number.
Exit Values: If the VM/SP system currently executing does not support the DIAGNOSE code X'OO' instruction, no data is returned to the virtual machine. If
it does support the DIAGNOSE code X'OO' instruction, the following data is
returned to the virtual machine (at the location specified by Rx):
Field System Name
Version
Number
Version
Code
MCEL
Processor
Address
Userid Program Product Bit
Map Descri,etion "VM/SP" The first byte is the version number, the
second byte is the level, and the third byte is
the PLC (Program Level Change) number. VM/SP executes the STIDP (Store Process-
or ID) instruction to determine the version
code. VM/SP executes the STIDP instruction to
determine the maximum length of the
MCEL (Machine Check Extended Logout)
area. VM/SP executes the ST AP (Store Processor
Address) instruction to determine the
processor address.
The userid of the virtual machine issuing the DIAGNOSE. Identifies the program products that are
installed. Valid values and the program
products each identifies are:
Characteristics
8 bytes, EBCDIC
3 bytes, hexadecimal
1 byte, hexadecimal
2 bytes, hexadecimal
2 bytes, hexadecimal
8 bytes, EBCDIC
8 bytes, hexadecimal
Value X'SOOOOOOOOOOOOOOO' X'COOOOOOOOOOOOOOO' X'EOOOOOOOOOOOOOOO' X'FOOOOOOOOOOOOOOO' X'FSOOOOOOOOOOOOOO' Program Product
Basic System Extensions 2
System Extensions, Release 2
VM/System Product, Release 1
VM/System Product, Release 2
VM/System Product, Release 3 DIAGNOSE Instruction in a Virtual Machine 223

Time Zone
Value
Represents the time zone differential in sec-4 bytes, hexadecimal
onds from Greenwich Mean Time. UNUSED 4 bytes, zeroes
Note: The Time Zone Value is a signed hexadecimal fullword value in seconds.
Negative values represent differentials west of Greenwich Mean Time and positive
values represent differentials east of Greenwich Mean Time. If VM/SP is execut­
ing in a virtual machine, another 40 bytes, or less, of extended identification data is
appended to the first 40 bytes described above. Up to five nested levels of VM/SP virtual machines are supported by this diagnose instruction resulting in a maximum
of 200 bytes of data that can be returned to the virtual machine that initially issued
the DIAGNOSE instruction. Upon return, Ry contains its original value less the number of bytes that were
stored.
Completion and Condition Codes: No completion code is returned, and the condition
code remains unchanged. DIAGNOSE Code X'04' -- Examine Real Storage
Privilege class C or E
Entry Values: Execution of a DIAGNOSE Code X'04' allows a user to examine
real storage. The register specified as Rx contains the virtual address of a list of
CP (real) addresses to be examined. The register contains the count of entries
in the list. Ry+ 1 contains the virtual address of the result field. The result field
contains the values retrieved from the specified reallocations.
Exit Values: For each address in the list of CP addresses, VM/SP provides a
fullword of data obtained from the specified address in real storage. VM/SP stores
this data into the result field identified by the Ry + 1 register.
There is a one-to-one correspondence between entries in the list of addresses and
entries in the result field. For example, data obtained from the address in the first
entry of the address list is stored in the entry of the result field, data obtained from
the second entry of the address list is stored in the second entry of the result field,
and so forth.
Usage Notes: The request and result tables must be in the same page of virtual stor­
age, and that page must be resident in real storage, at the time the DIAGNOSE is
executed. This is guaranteed if the instruction itself is also in the same page.
In the attached processor or multiprocessor environment, each processor has a pre­
fix register to relocate addresses between 0 and 4095 to another page frame in
main storage. The prefix register enables each processor to use a different page
frame in order to avoid conflict with the other processor for such activity as inter­
rupt code recording. Thus, the range 0 through 4095 refers to different areas of
storage, depending upon which processor generates the address.
In attached processor mode, all references to main storage from either processor
are handled as if they were made on the main processor. In multiprocessor mode,
224 VM/SP System Programmer's Guide