Notes

Notes

T o o l s
-Assembler
--Package examples
--Script examples
--Jas API
--Scripting API
--Notes

The Java VM spec on May 28, 1996 appears to be vague or incorrect about the wide instruction, these are my notes on how the Solaris JDK VM implementation of the wide instruction on Mar 28, 1996 works.

Note: Wide instructions are generated automatically from the Jas package as necessary, and it creates them in the format which the current implementation understands, not what is specified in the VM spec.

A wide instruction for storing/loading is actually laid out as

       [opc_wide]
       [opc_instruction being modified]
       [vindex1]
       [vindex2]

opc_ret can also be "widened"
opc_ret_w appears to be removed in the current implementation (thanks to Steve Lee, sjlee@newmonics.com) for pointing this out.
When you prefix opc_wide to opc_iinc, both the vindex and the constant become 16 bit quantities, vindex unsigned as usual, and the constant signed.
```
       [opc_wide]
       [opc_iinc]
       [vindex1]
       [vindex2]
       [const1]
       [const2]
```

T o o l s/Assembler

Package examples | Script examples | Jas API | Scripting API | Notes

http://www.sbktech.org/jas_apn.html Revised: Thu Dec 19 08:51:14 1996
Copyright (C) 1996 KB Sriram.
Comments, bug reports: kbs@sbktech.org
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