Integer absolute value in MIPS?

Here is a pretty simple way to do it.

#assume you want the absolute value of r1
        ori $2, $zero, $1      #copy r1 into r2
        slt $3, $1, $zero      #is value < 0 ?
        beq $3, $zero, foobar  #if r1 is positive, skip next inst
        sub $2, $zero, $1      #r2 = 0 - r1
foobar:
#r2 now contains the absolute value of r1

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