On 01/14/2017 10:27 PM, Segher Boessenkool wrote:
On Sat, Jan 14, 2017 at 09:47:41PM -0700, Jeff Law wrote:
PR target/72749
* cfgrtl.c (rtl_split_edge): Also patch jump insns that jump to the
fallthrough.
* haifa-sched.c (dump_insn_stream): Don't crash if there is a label
in the currently scheduled RTL fragment.
So presumably the semantics in this case can only mean one thing -- both
the fallthru and the jump have to go to the same place after splitting.
Right? ISTM that ought to be documented in rtl_split_edge somewhere.
We could call patch_jump_insn in *all* cases, except for simple jumps
it does
gcc_assert (JUMP_LABEL (insn) == old_label);
which is a useful check (for the other callers), and patch_jump_insn
isn't a very cheap routine to call anyway, better not do it too often.
In this case is the edge a fallthru or branch edge?
Both! You get only one edge if both jump targets are the same.
Right. To be more precise, my question was does it have EDGE_FALLTHRU
set?
Jeff
