[Bug target/117939] [15 Regression] nvptx: CRC test cases execution test FAILs

[law at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117939

--- Comment #2 from Jeffrey A. Law <law at gcc dot gnu.org> ---
While it may not been been obviously related to the CRC work, the testcase
itself looks like a CRC to me.  It's almost certainly the case that the CRC
pass is detecting it and turning it into a table lookup.  And based on your
various comments it seems like something in that path is tickling problems on
nvptx.

It looks like at -O3 the loop is unrolling and that in turn defeats the CRC
detection code, which isn't a huge surprise.