U - Unassemble

Unassemble storage at a given address.

Syntax:

──── U  ───────────────────┬──────────┬───────────────────────
                             └── addr ──┘

Parameters:

addr

The address of the storage location to be unassembled.

Results & Notes:

The U command unassembles storage from the address given. No attempt is made to distinguish between code and data storage. If no addr is given then the default address is determined in order of precedence as follows:

• The last unassembled address + 1, or

• The CS:EIP of the last explicitly executed .R command or R command, or

• The address of the next instruction to be executed.

The U command takes its default addessing mode as set by by the R or .R commands. Prior to fix pack 29 for Warp 3.0 and base Warp 4.0 V8086 addessing mode was ignored by the Dump Formatter unless explicitely specified by using the & addressing operator.

Output from the U command is in two forms depending on whether the storage address was set in the context of the default (Kernel Debugger's or Dump Formatter's current) thread slot or another slot. In the former case output appears as in the following example:

-------------------------------------------------------------------------------##u
0170:fff4521f 803d9e53e0ffff cmp     byte ptr [InterruptLevel (ffe0539e)],ff
0170:fff45226 75b4           jnz     fff451dc
0170:fff45228 803d9643e0ff00 cmp     byte ptr [_cTKNoBlock (ffe04396)],00
0170:fff4522f 75be           jnz     fff451ef
0170:fff45231 0f01e1         smsw    cx
0170:fff45234 66f7c10200     test    cx,0002
0170:fff45239 0f8552050000   jnz     fff45791
0170:fff4523f fa             cli
-------------------------------------------------------------------------------

In the latter case the context is shown by prefixing the thread slot to the address as in the following example:

-------------------------------------------------------------------------------
##.p*

 Slot  Pid  Ppid Csid Ord  Sta Pri  pTSD     pPTDA    pTCB     Disp SG Name
*0022# 0013 0003 0013 0001 blk 0300 7b6ea000 7b8c7128 7b8ab820 1eb8 18 epm
##.r 34

eax=00000000 ebx=000007f4 ecx=00000000 edx=0003ace7 esi=d02f4ef0 edi=000011ec
eip=0000272d esp=0000755e ebp=00007566 iopl=2 -- -- -- nv up ei ng nz na pe nc
cs=d02f ss=001f ds=bccf es=ace7 fs=150b gs=000  cr2=15b20000  cr3=001d9000
doscall1:CONFORM16:postDOSSEMWAIT:
0034|d02f:0000272d c9        leave
##u

doscall1:CONFORM16:postDOSSEMWAIT:
0034|d02f:0000272d c9        leave
0034|d02f:0000272e ca0800    retf    0008
0034|d02f:00002731 87db      xchg    bx,bx
0034|d02f:00002733 90        nop
doscall1:CONFORM16:DOSSEMSET:
0034|d02f:00002734 c8040000  enter   0004,00
0034|d02f:00002738 8b4608    mov     ax,word ptr [bp+08]
0034|d02f:0000273b 3d0200    cmp     ax,0002
0034|d02f:0000273e 7448      jz      2788
0034|d02f:00002740 250300    and     a,0003
0034|d02f:00002743 3d0100    cmp     ax,0001
0034|d02f:00002746 7415      jz      275d
0034|d02f:00002748 8b4608    mov     ax,word ptr [bp+08]
##-------------------------------------------------------------------------------

Note:

The unassembled instruction mnemonics may be toggled between upper and lower case by use of the Y command.

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