RFR: 8331575: C2: crash when ConvL2I is split thru phi at LongCountedLoop

[Roland Westrelin]

On Mon, 6 May 2024 07:31:22 GMT, Christian Hagedorn <chagedorn at openjdk.org> wrote:

> But I'm still wondering though, if these bailouts are really needed in the general case. It seems like this problem is mainly for loop phis. Couldn't we check the types of loop phi inputs and bail out if one includes zero?

Are we sure divisions are the only cause of bugs? My understanding of this issue is that once pushed thru phi, the type of the `ConvL2I` is simply not correct and that's the root cause. I wonder if we could get other failures because of this: maybe a node becoming top because of the incorrect type or an out of bound array access.

-------------

PR Review Comment: https://git.openjdk.org/jdk/pull/19086#discussion_r1590910489