Introduction.

Workshop PG5
Instructionlist
Labels:
You can make conditional and unconditional jumps in your programs. When
you jump in your program, you have to tell the assembler where you want to
jump to. Labels are symbol names given to locations in a program (program
lines), which are used as destinations for jump instructions.
Characters allowed in labels are the same as those of symbols. Labels can appear
anywhere in the source file, but should be within a code block (COB, PB
etc.), and must not be inside a multi-line instruction.
The value assigned to a label is its offset within the code block where it is defined.
All labels are local to the block in which they are defined, and the same
label can be used many times in the same source module, providing it is always
in a different block. Jumps to labels defined in another block are not allowed.
Example:
Range of symbols
and labels:
Symbols are always "local". Which means that the symbol name is only known
to instructions, which are in the same file as the declaration (see chapter 3). If
you have a symbol with the same name in another file, then the data of the two
symbols won’t get mixed up.
Labels are always local to the block. You can't jump from one file to the other
or from one block to the other. Even if the two blocks are in the same file.
All COB’s, XOB’s, PB’s, FB’s, SB’s, IST’s, ST’s, TR’s, TEXT’s, and
DB’s, are globally known
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