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Parameters

PATCH INSERT — VMS 5.0

Use INSERT to insert VAX/VMS  MACRO  instructions  into  specific
locations  within  an  image file.  To use this command, you must
specify  the  /INSTRUCTION  qualifier  or  you   must   set   the
INSTRUCTION  mode.   To insert additional data into a patch area,
use the DEPOSIT/PATCH_AREA command.

Before inserting the new instruction, the INSERT command confirms
the  contents  of  the location preceding the insertion (that is,
that current instruction).

When the INSERT command is  executed,  it  replaces  the  current
instruction  with  a  branch  instruction  and places the current
instruction and the new instructions in the current  patch  area.
The   last  new  instruction  is  always  followed  by  a  branch
instruction that redirects the flow  of  execution  back  to  the
inline  code.   The INSERT command automatically generates branch
instructions.

After the insertion of new instructions, the  patch  area  string
descriptor is updated to reflect the modifications.

If the branch instruction to the patch area is  longer  than  the
current   instruction,   additional  instructions  following  the
current instruction are also moved to the  patch  area,  and  the
branch  instruction is deposited in the vacated memory locations.
Unused memory locations are filled with NOP instructions.  If the
current  instruction  is  longer than the branch instruction, the
unused memory locations are filled with NOP instructions.

PATCH  calculates  the  relative  displacements  for  the  branch
instructions   it   generates   and   recalculates  the  relative
displacements for all branch-type instructions moved to the patch
area.  Instructions and data moved to patch area may, however, be
referenced by instructions not affected by the move.   Note  that
PATCH  does  not  recalculate  any  relative displacements in the
unaffected instructions.

Note also that if PATCH  moves  an  instruction  with  a  current
address  defined  by a symbolic instruction label, you must check
and correct any references made to that label.

Format:

     INSERT location = current-instruction
     new-instruction
             .
             .
             .

          Mode Qualifiers                 Defaults
          ____ __________                 ________

          /OCTAL
          /DECIMAL                        /HEXADECIMAL
          /HEXADECIMAL

          /[NO]INSTRUCTION                /NOINSTRUCTION
          /[NO]SYMBOLS                    /SYMBOLS
          /[NO]GLOBALS                    /NOGLOBALS
          /[NO]SCOPE                      /SCOPE

Prompts:

        LOC> location
        OLD> current-instruction
        NEW> new-instruction

Additional information available:

Parameters

Parameters

location
     Specifies the address after which one or  more  new  instructions
     are to be added.

current-instruction
     Specifies  the  instruction  currently  occupying  the  specified
     location.

new-instruction
     Specifies one or more new instructions to be  inserted  into  the
     image file following the current instruction.


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