How to determine if a variable has been discarded

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#1

Hi all,

When I check the ll code, I found sometimes an operation has one or more "undef" operands. Does that means this operations has been discarded? What I want to check is how to determine which variables have been discarded. If I decide to discard everything that is transitively related to an undef then is that correct? If I implement that algorithm, is there a discard I'll be missing? Thanks.

Best,

Kecheng

#2

Hi Kecheng,

Undef means that there hasn't been a value assigned to a variable. If you're expecting to have initialized values for your variables, you have to specify that.

--Sam