On 8/26/2022 12:55 AM, Richard Biener via Gcc-patches wrote:
As written earlier uninit_analysis::use_cannot_happen is duplicate
functionality implemented in a complement way, not adhering to
the idea of disproving a may-uninit use and eventually (I have not
yet found a testcase it helps to avoid false positives) avoiding
false positives because of this or different ways it imposes limits
on the predicate computations.
This patch removes it.
I've bootstrapped and tested this before, but re-bootstrap/test
on x86_64-unknown-linux-gnu is running now.
* gimple-predicate-analysis.h
(uninit_analysis::use_cannot_happen): Remove.
* gimple-predicate-analysis.cc (can_be_invalidated_p): Remove.
(uninit_analysis::use_cannot_happen): Likewise.
(uninit_analysis::is_use_guarded): Do not call
use_cannot_happen.
ACK. IIRC Aldy added this several years back to deal with a uninit
regression PR. If it's not triggering anymore, I'm not going to lose
any sleep over losing it.
jeff
