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Spark assembly and% y register

I am currently working with a sparc computer and I am trying to find out if the number is prime or not.

here is a piece of code:

        mov     0,%y            
        mov     3, %l1
        nop
        nop
        nop

        sdiv    %l1,2,%l3
        rd      %y, %l6         
        cmp     %l6, 0

So the main thing we have is 3/2. So there should be reminder 1. This reminder should be placed in the% Y register. But when I look at% Y, it is still 0. Why is% Y still at 0 while it should show me a reminder of 1?

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2 answers


According to the SPARC Architecture Guide , page 116, this is an implementation option, whether or not to install% y in sdiv. Apparently, this is also an implementation option, be it to implement in hardware or software, so it seems that some software implementations don't set% y.



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Refer to the SPARC V8 manual on page 115 for the sdiv instruction, the CPU will discard the remainder.



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