Interested to Buy Any Domain ? << Click Here >> for more details...
Answer Posted / phil
neither DROP nor USING affect the register contents.
Once a register has been loaded with the address of a piece
of storage, the using statement can be used to 'map' that
storage against a set of labels defining the layout of that
storage e.g. a DSECT. Then whenever one of those labels is
referenced in the code, in moves etc, the assembler resolves
the relative address as a particular displacement from the
absolute address in the register. The DROP instruction
removes the relationship between the labels and the register
and renders subsequent references to those labels as
unresolvable, giving rise to errors at assembly (compile)time.
Typically the DROP instruction will be used to allow use of
the register for another purpose, e.g. address a different
bit of storage via a using staement on second DSECT without
the risk of corrupting that data via moves referencing the
original DSECT.
| Is This Answer Correct ? | 9 Yes | 0 No |
Post New Answer View All Answers
What will happen if we drop the base register in the program which contains only one basereg?
Explain about maximum displacement?
What is the use of trt instruction?
What is icm instruction?
What is house keeping in assembler?
Explain the difference between various read and find statement and which one should be used when for better adabas performance?
how to pass the parameters from jcl to assembler pgm?
In the house keeping section of an MVS assembly language program, like the one below STM R14,R12,12(R13) BASR R12,R0 USING *,R12,R11 LA R11,2048 LA R11,2048(R11,R12) .... .... 1. What if BASR R12,R0 IS NOT PRECEDE USING *,R12,R11? 2. USING (base address), REGISTER does USING directive says assembler to treat particular Register as a base register with the mentioned base address..in the above case * i.e current location counter..well if that is the case why we need BASR R12,R0 ? 3. What if I write like STM R14,R12,12(R13) BASR R12,R0 LA R11,2048 LA R11,2048(R11,R12) USING *,R12,R11 there is no address resolution being calculated in both LA statements so is it a right way to set Base register?..will there be any issues with Domain regarding R11 and R12?
how to initialize a register to 0000?
How do you round the addition or subtraction of two numbers in assembler?
How is data passed from a calling program to an assembler called program?
Explain about base register?
how to retrieve the instream data in sysin?
Explain the difference between various read and find statement?
Ap wkur,=p5 where wkur is a label?
