[LLVMdev] creating SCEV taking too long

Daniel Berlin dberlin at dberlin.org
Tue Jul 30 18:41:10 PDT 2013


On Mon, Jul 29, 2013 at 8:48 PM, Guo, Xiaoyi <Xiaoyi.Guo at amd.com> wrote:
> Thank you very much for your reply.
>
>
>
> Do you mean calculate the hash based on element SCEV pointers?

No, based on the properties of them (IE type, etc).  It will be
entirely deterministic
You have two cases: Either all these SCEV's are really the same, in
which case, this will do nothing
Or they are subtly different, but right now it's comparing 128
operands to find out.

The hash helps with the second case, but not the first.



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