> A 3-pointer reg note seems a bit heavyweight for a boolean anyway.
> JUMP_INSNs have a quite a few unused rtx header flags (including "jump",
> ironically) so this patch records the information there instead.
>
> This reduces the compile time by about ~0.5%. Not a huge amount,
> but maybe it co
find_reg_note showed up in the profile of a -O2 compile of an oldish
fold-const.ii. The main hot call was:
/* If we are partitioning hot/cold basic_blocks, we don't want to mess
up jumps that cross between hot/cold sections.
Basic block partitioning may result in some jum
