[LLVMdev] Last use of operand within BasicBlock?

[Duncan Sands]

Hi Ryan,

> Given an instruction and the basic block that it's in, is there an easy way to
> tell if the operands are ever referenced after the instruction?

if the operand only has one use (->hasOneUse()) then you know it.  Otherwise it
is more tricky.  Why do you care?

Ciao, Duncan.

>
> For example, if i have
> ...
> %mul = mul nsw i32 %a, %val
> %add = add nsw i32 %b, %val
> ...
>
> And I'm iterating through this basic block, can I tell when I get to the
> multiply instruction that another instruction is going to be using %val?
>
> Since I'm running my code through reg2mem, I don't really care much about other
> basicblocks (anything outside the basicblock should have an eliminated phi
> instruction so it will be pulled from memory anyways).
>
>
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