[amp_mcq option1=”independent two-pass processor” option2=”independent one-pass processor” option3=”processor incorporated into pass 1 of a standard two-pass assembler” option4=”all of the above E. None of the above” correct=”option4″]
The correct answer is D. all of the above.
A macro processor is a program that takes a macro definition as input and expands it into a sequence of instructions that can be executed by the assembler. Macro processors can be implemented in a number of ways, including as an independent two-pass processor, an independent one-pass processor, or as a processor incorporated into pass 1 of a standard two-pass assembler.
In an independent two-pass processor, the macro processor first reads the macro definition and stores it in memory. It then reads the source code line by line and expands any macros that it finds. This process is repeated until all of the source code has been processed.
In an independent one-pass processor, the macro processor reads the source code line by line and expands any macros that it finds as it goes along. This process is faster than the two-pass approach, but it can be more difficult to implement correctly.
In a processor incorporated into pass 1 of a standard two-pass assembler, the macro processor is part of the assembler itself. The assembler first reads the source code line by line and expands any macros that it finds. It then passes the expanded code to the second pass of the assembler, which performs the actual assembly. This approach is the most efficient, but it can be more difficult to modify the macro processor if necessary.
In conclusion, a macro processor can be implemented in a number of ways, including as an independent two-pass processor, an independent one-pass processor, or as a processor incorporated into pass 1 of a standard two-pass assembler. The best approach to use depends on the specific needs of the application.