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Answer:

Set instructions set a register to 1 or clear it to 0 to show the outcome of a comparison between two values.


Set on Less Than

Think of the "1" and "0" that a set instruction puts in the flag register as "true" and "false". Here is the slt from chapter 18, but now made more useful by the extended assembler:

                   #  $s and t contain   
                   #  two's comp. integers
                   #  t can be a register 
                   #  or an immediate operand
                   #
slt   d,s,t        #  if ( $s < t )
                   #    d = 1
                   #  else
                   #    d = 0
                   #
                   #  (pseudoinstruction)

With the extended assembler, the operand t can be an immediate operand.


QUESTION 9:

Is the following correct?

slt   $t5,$v0,87        #  if ( $v0 < 87 ) $t5 = 1