DIS

Syntax

   DIS nmword [virtaddr]
   DIS cmword1 [cmword2] [cmlogaddr]

The DCx (display code) commands can be used to display a block of code at a specified address. The program windows also display disassembled code.

Examples

   $nmdebug > dis 6bc23fd9
   STW      2,-20(0,30)

This NM example disassembles the NM word $6bc23fd9 into the STW instruction.

   $nmdebug > dis e84001d8
   BL       $000000f4,2
   $nmdebug > dis e84001d8, a.4adeb4
   BL       test_proc+$68,2

This NM example disassembles the word $e84001d8 into a BL instruction. In the second command, the virtual address of the instruction is specified, and the disassembler is able to compute and to display the effective procedure name target of the branch.

   %cmdebug > dis 41101
   LOAD  DB+%101

This CM example disassembles the single CM word %41101 into the LOAD DB+%101 instruction.

   %cmdebug > dis 20477 43
   LDDW  SDEC=1

This CM example disassembles the two CM words, %20477 and %43, into the LDDW SDEC=1 instruction.

   %cmdat > dis 31163
   PCAL %163
   %cmdat > dis 31163,,sys(25.0)
   PCAL ?SWITCH'TO'NM'
   %cmdat > dis 31163,,sys(1.0)
   PCAL ?ATTACHIO

These CM examples involve the CM PCAL instruction. In the first example, 31163 is recognized as the PCAL instruction, but the STT number is invalid for the current CM segment. In the second example, the instruction is disassembled as if it were found in CM logical segment SYS %25, and the resulting destination of the PCAL is displayed as ?SWITCH'TO'NM. The third example indicates that within CM logical segment SYS 1, the resulting target of a PCAL %163 is ?ATTACHIO.

   %cmdat > var n 1
   %cmdat > while 1 do {w "stt: " n:"w3" "  " ;dis 31000+n; var n n+1}
   stt:   %1  PCAL ?TERMINATE
   stt:   %2  PCAL ?TERMINATE
   stt:   %3  PCAL ?ABORTJOB
   stt:   %4  PCAL ?ACTIVATE
   stt:   %5  PCAL ?ADOPT
   stt:   %6  PCAL ?ONENET'ADOPT
   stt:   %7  PCAL ?CREATEPROCESS
   stt:  %10  PCAL ?EXEC'TERMINATE
   stt:  %11  PCAL ?GET'PLFD'TBLPTR
   stt:  %12  PCAL ?GETORIGIN
   stt:  %13  PCAL ?GETPRIORITY
   stt:  %14  PCAL ?GETPROCID
   stt:  %15  PCAL ?GETPROCINFO
   stt:  %16  PCAL ?JSM'TO'CI'PIN
   stt:  %17  PCAL ?KILL
   stt:  %20  PCAL ?PROCINFO
   stt:  %21  PCAL ?PROCTIME
   stt:  %22  PCAL ?SET'JSM'TIME'LI
   stt:  %23  PCAL ?SET'PLFD'TBLPTR
   stt:  %24  PCAL ?SUSPEND
   stt:  %25  PCAL ?XCONTRAP
   stt:  %26  PCAL ?NM'BREAKCONTROL
   stt:  %27  PCAL ?SETSERVICE
   stt:  %30  PCAL ?REQUESTSERVICE
   stt:  %31  PCAL ?RESETCONTROL
   stt:  %32  PCAL ?CAUSEBREAK
   stt:  %33  PCAL ?CAUSEBREAK'
   stt:  %34  PCAL ?BRK'IN'BREAK
   stt:  %35  PCAL ?BRK'ABORT
   stt:  %36  PCAL ?BRK'RESUME
 
   control-Y encountered
   %cmdat >

This example demonstrates how a simple loop can be used to display the targets for each STT entry within the current CM segment. Since we know that %31000 is the PCAL instruction, we simply add the desired STT number and use the DIS command to display the target entry point name. Control-Y is used to terminate the loop.

Limitations, Restrictions

none