[Bug rtl-optimization/57067] Missing control flow edges for setjmp/longjmp

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57067

--- Comment #5 from Richard Biener <rguenth at gcc dot gnu.org> ---
The RTL except.c:can_nonlocal_goto () function does not consider setjmp.
Does

Index: gcc/except.c
===================================================================
--- gcc/except.c        (revision 198867)
+++ gcc/except.c        (working copy)
@@ -1936,7 +1936,9 @@ insn_nothrow_p (const_rtx insn)
 bool
 can_nonlocal_goto (const_rtx insn)
 {
-  if (nonlocal_goto_handler_labels && CALL_P (insn))
+  if ((nonlocal_goto_handler_labels
+       || cfun->calls_stjmp)
+      && CALL_P (insn))
     {
       rtx note = find_reg_note (insn, REG_EH_REGION, NULL_RTX);
       if (!note || INTVAL (XEXP (note, 0)) != INT_MIN)

fix it?

For retaining edges we have to teach find_many_sub_basic_blocks to treat
abnormal outgoing edges similar to EH outgoing edges - they have to be
re-directed from the block ending in the actual call (and made
EDGE_ABNORMAL_CALL which doesn't exist on the GIMPLE CFG).

Also

          if ((e->flags & EDGE_ABNORMAL)
              && !(e->flags & EDGE_SIBCALL))
            remove_edge (e);

will happily remove an EDGE_FALLTHRU|EDGE_ABNORMAL edge.