> That's what I believe, too. Still, combine appears to add REG_UNUSED > notes for clobbers intentionally. Do you know why it does that?
Hmm, right, it apparently clearly wants to immediately close the "live" ranges it creates by adding new clobbers. And, indeed, regrename.c for example uses these CLOBBER/REG_UNUSED pairs to compute live ranges for non-operands (the pass does its own forward scan of the insn stream). So DF's choice might have been made explicitly after all... -- Eric Botcazou
