https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69447
--- Comment #13 from Richard Henderson <rth at gcc dot gnu.org> --- (In reply to Jakub Jelinek from comment #11) > Without knowing the lra-remat code at all, I just wonder if subreg_regs > needs to be one per the whole function, rather than say per extended basic > block or basic block, with the patch any uses in multi-reg subregs anywhere > in the function will affect remat of all other spots where it is used. I started with subreg_regs being per-block. But since IRA has some global component, I was concerned that there would be some edge case that would be missed, and switched to a global bitmap. Perhaps someone who knows the allocator better can comment.