DEBUG Subcommands-GO GO Use the GO subcommand to exit from the debug environment and begin
program The format of the GO subcommand is: r 1 , , , GO I r , symbol I , hexloc , , , , , L J L
symbol is the symbolic name assigned to the storage location where you want execution to begin.
hexloc is the hexadecimal location, in relation to the current
origin, where you want execution to begin.
1. When you issue the GO subcommand, the general registers, CAW (channel address word), and CSW (channel status wordt are restored
either to their contents upon entering the debug environment, or,
if they have been modified, to their modified contents. Then the
old PSW is loaded and becomes the current PSW. Execution begins at
the instruction address contained in bits 40-63 of the PSW. 2. When you specify symbol or hexloc with the GO subcommand, the
specified address replaces the instruction address in the old PSW, so execution will begin at that address. If you entered the debug environment with the DEBUG command, you must specify an address
with the GO subcommand.
3. The address you specify must be within your virtual machine and it
must contain a valid operation code.
Program execution is resumed. Section 4. DEBUG Subcommands 269

DEBUG Subcommands-GPR, HX GPR Use the GPR subcommand to display the contents of one or more general
registers at the terminal. The format of the GPR subcommand is: r '--------------------------, I GPR I reg 1 r reg2 1 1 L- regl is a decimal number (from 0-15 inclusive) indicating the first
or only general register whose contents are to be displayed.
reg2 is a decimal number (from 0-15 inclusive) indicating
general register whose contents are to be displayed.
be larger than reg1.
the last
reg2 must register or registers specified are displayed, in hexadecimal
representation:
xxxxxxxx
HX Use the subcommand to leave
reason the debug environment
su bcomma nd is: r I L- the debug environment, regardless of the
was entered. The format of the HI
If you entere1 the debug environment following a program interruption,
you receive the message: CMS to indicate a return to the CMS environment. If you entered the debug
environment by issuing the DEBUG command, you receive the message:
DMSABN148T SYSTEM ABEND 2E4 CALLED FROM xxxxxx
where xxxxxx is the address of the debug routine. 2
7 0 IBM VM/370 CMS Command and Macro Reference