On 7/29/2022 2:47 AM, Richard Biener via Gcc-patches wrote:
The forward threader failed to check whether it can actually duplicate
blocks. The following adds this in a similar place the backwards threader
performs this check.
Bootstrapped and tested on x86_64-unknown-linux-gnu, pushed.
PR tree-optimization/106422
* tree-ssa-threadupdate.cc (fwd_jt_path_registry::update_cfg):
Check whether we can copy thread blocks and cancel the thread if not.
* gcc.dg/torture/pr106422.c: New testcase.
I'm back from PTO. This looks obviously correct to me.
jeff
