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Answer:

Yes: the programmer must know the address in advance.


Load Address Pseudoinstruction

It is not always possible to know the address in advance. Conveniently, symbolic addresses and systems software make this unnecessary. This happens by using the la mnemonic. This mnemonic does not correspond to a single machine instruction. It is a pseudoinstruction that the assembler translates into to several machine instructions.

la   d,exp          #  load register $d with the address
                    #  described by the expression "exp"
                    #  "exp" is often a symbolic address
                    #  (pseudoinstruction)

In this pseudoinstruction, exp is an expression that evaluates to a memory address. There are several possible forms for exp. Often it is a symbolic address. The la pseudoinstruction translates into different machine code instructions depending on exp.


QUESTION 15:

Does the la instruction access (look at) memory?