Richard Biener <richard.guent...@gmail.com> writes: >> Am 21.08.2025 um 16:56 schrieb Richard Sandiford <richard.sandif...@arm.com>: >> >> This PR is another bug in the rtl-ssa code to manage live-out uses. >> It seems that this didn't get much coverage until recently. >> >> In the testcase, late-combine first removed a register-to-register >> move by substituting into all uses, some of which were in other EBBs. >> This was done after checking make_uses_available, which (as expected) >> says that single dominating definitions are available everywhere >> that the definition dominates. But the update failed to add >> appropriate live-out uses, so a later parallelisation attempt >> tried to move the new destination into a later block. >> >> Sorry that this seems to be a recurring source of bugs. >> I'll try to think of a way of testing and structuring it better. >> >> Tested on aarch64-linux-gnu & x86_64-linux-gnu. OK to install? > > Ok.
Thanks. > Does this also fix the arm32 bootstrap issue? I'm not sure yet. I didn't get chance to reproduce it there, so I'll have to throw myself at the mercy of the bug reporter or colleagues to test. Richard
