| 0 = | No |
| 1 = | Yes |
| 0 = | No |
| 1 = | Yes |
| 0 = | No |
| 1 = | Yes |
| Op Code (Hex) | Operand 1 | Operand 2 | Operand 3 | |
|---|---|---|---|---|
| 0283 | Program to be called or call template | Argument list | Return list |
Operand 2: Operand list or null.
Operand 3: Instruction definition list or null.
The following information is subject to change from release to release. Use it with caution and be prepared to adjust for changes with each new release.
The instruction preserves the calling invocation and passes control to either the program entry procedure of a bound program or the external entry point of a non-bound program. If operand 1 specifies a Java program or a bound program which does not contain a program entry procedure, an invalid operation for program (hex 2C15) exception is signaled.
Operand 1 may be specified as a system pointer which directly addresses the program that is to receive control or as a space pointer to a call template which identifies the program to receive control. Specifying a template allows for additional controls over how the specified program is to be invoked. The format of the call template is the following:
| Offset | |||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Dec | Hex |
| Field Name |
| Data Type and Length | ||||||||||||
| 0 | 0 |
| Call options |
| Char(4) | ||||||||||||
| 0 | 0 |
| Suppress adopted user profiles |
| Bit 0 | ||||||||||||
|
|
|
|
| ||||||||||||||
| 0 | 0 | Reserved (binary 0) | Bits 1-29 | ||||||||||||||
| 0 | 0 | Prefer teraspace storage | Bit 30 | ||||||||||||||
| |||||||||||||||||
| 0 | 0 |
| Force thread state to user state for call |
| Bit 31 | ||||||||||||
|
|
|
|
| ||||||||||||||
| 4 | 4 |
| Reserved (binary 0) |
| Char(12) | ||||||||||||
| 16 | 10 |
| Program to be called |
| System pointer | ||||||||||||
| 32 | 20 |
| --- End --- |
|
| ||||||||||||
The suppress adopted user profiles call option specifies whether or not the program adopted and propagated user profiles which may be serving as sources of authority to the thread are to be suppressed from supplying authority to the new invocation. Specifying yes causes the propagation of adopted user profiles to be stopped as of the calling invocation, thereby, not allowing the called invocation to benefit from their authority. Specifying no allows the normal propagation of adopted and propagated user profiles to occur. The called program may adopt its owning user profile, if necessary, to supplement the authority available to its invocation.
The prefer teraspace storage option specifies whether
or not to give preference to the teraspace storage model when
determining the target activation group on a call to a
bound program with callers activation group, inherit or teraspace
storage model and user state.
This option is ignored for the following cases:
When prefer teraspace storage specifies yes,
preference is given to the teraspace user-state default activation
group when no invocation-associated activation group satisfies
the target activation group requirement.
The force thread state to user state option specifies whether or not the call changes the state of the thread to user state.
Operand 2 specifies an operand list that identifies the arguments to be passed to the invocation entry to be called. If operand 2 is null, no arguments are passed by the instruction. An argument list length violation (hex 0802) exception is signaled if the number of arguments passed does not correspond to the number required by the parameter list of the target program.
Operand 3 specifies an instruction definition list (IDL) that identifies the instruction number(s) of alternate return points within the calling invocation. A Return External instruction in an invocation immediately subordinate to the calling invocation can indirectly reference a specific entry in the IDL to cause a return of control to the instruction associated with the referenced IDL entry. If operand 3 is null, then the calling invocation has no alternate return points associated with the call. If operand 3 is not null and operand 1 specifies a bound program, an invalid operation for program (hex 2C15) exception is signaled.
The details of processing differ for non-bound and bound programs. The following outlines the common steps.
The details of locating the target activation group and activating the program differ depending upon the model of the program.
A bound program is activated and run in an activation group specified by program attributes. There are two logical steps involved:
After locating the activation entry for the program, control is passed to the program entry procedure for the program. If required, the activation group is destroyed when the invocation for the program entry procedure is destroyed.
The automatic storage frame begins with a 64 byte header. If the program defines no automatic data items the frame consists solely of the 64-byte header, otherwise the automatic storage items are located immediately following the header. In prior releases of the machine, this header contained invocation information which is now available via the Materialize Invocation Attributes (MATINVAT) instruction. This header is not initialized and the contents of the header are not used by the machine. (The space is allocated merely to provide for compatibility with prior implementations of the machine.) The update PASA stack program attribute, supported in prior implementations of the machine, is no longer meaningful and is ignored, if specified as an attribute of the program.
Following the allocation and initialization of the invocation entry, control is passed to the invoked program.
06 Addressing
08 Argument/Parameter
0A Authorization
10 Damage Encountered
1A Lock State
1C Machine-Dependent
20 Machine Support
22 Object Access
24 Pointer Specification
2A Program Creation
2C Program Execution
2E Resource Control Limit
36 Space Management
38 Template Specification
44 Protection Violation