HLASM: V1R6 Language Ref

Assembler language coding conventionsv When converting existing programs for assembly with the DBCS option, ensurethat continuation-indicators are different from the adjacent data in the endcolumn.v The extended continuation-indicators must not be extended into the continuecolumn, otherwise the extended continuation-indicators are treated as data, andthe assembler issues the following error message:ASMA205E Extended continuation column must not extend into continuecolumnv For SI and SO to be removed at continuation points, the SI must be in the endcolumn, and the SO must be in the continue column of the next line.Examples:Name Operation Operand Continuation│DBCS1 DC C’XXXXXXXXXXXXXXXXXXXX’DBCS2 DC C’abcdefghijklmnopqrstuvwxyz0123456789XXXX’DBCS3 DC C’abcdefghijklmnopqrstuvXX’DBCS1DBCS2DBCS3The DBCS1 constant contains 11 double-byte characters bracketed by SO andSI. The SI and SO at the continuation point are not assembled into theoperand. The assembled value of DBCS1 is:The DBCS2 constant contains an EBCDIC string which is followed by adouble-byte string. Because there is no space for any double-byte data onthe first line, the end column is extended three columns to the left and thedouble-byte data started on the next line. The assembled value of DBCS2 is:abcdefghijklmnopqrstuvwxyz0123456789The DBCS3 constant contains 22 EBCDIC characters followed by 9double-byte characters. Alignment of the double-byte data requires that theend column be extended one column to the left. The SI and SO at thecontinuation point are not assembled into the operand. The assembledvalue of DBCS3 is:abcdefghijklmnopqrstuvSource listing considerations:v For source that does not contain substituted variable symbols, the listing exactlyreflects the source input.v Double-byte data input from code-generation programs, that contain nosubstituted variables, are not readable in the listing if the source input was notdisplayable on a device capable of presenting DBCS characters.v Refer to “Listing of generated fields containing double-byte data” on page 247for details of extended continuation and macro-generated statements.Chapter 2. Coding and structure 17