[llvm-dev] Normalize a SCEV Expression

[Stefanos Baziotis via llvm-dev]

Hi,

I have a SCEV like this: {16,+,8}. Say that this came from a loop like:
int64_t *p;
for (int64_t i = 0; i < ...; ++i)
  p[i+2]...

And assuming that I'm on a 64-bit machine. What I would like to do is
normalize it
like that, basically this: {2,+,1} i.e. map it to the index.

Now, I tried to get the underlying element size of the pointer, then
getUDivExpr(OriginalSCEV, ElementSize); But I don't get the desired SCEV
back. Instead I'm getting:
{16,+,8} \u 8, i.e. just adding udiv in the original expression.

Why is this not simplified?

Thanks,
Stefanos Baziotis
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