https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91580
--- Comment #11 from Uroš Bizjak <ubizjak at gmail dot com> --- (In reply to Richard Biener from comment #10) > Created attachment 46778 [details] > untested patch > > Added missing df_insn_rescan, also if there is more than one reaching def for > the use we cannot simply replace it but we have to reset it (since we cannot > emit the "merge" copy). Not sure if we could emit a duplicate debug-insn > and if that would help (maybe in the even RA assigns the same reg which is > unlikely since we want xmm regs here). IIRC, timode_scalar_chain hit some problems with debug insns. Perhaps timode_scalar_chain::fix_debug_reg_uses can be generalized also for DImode and SImode chains.
