On Tue, Mar 25, 2025 at 08:33:41AM -0700, Andi Kleen wrote:
> > 2025-03-25 Jakub Jelinek <[email protected]>
> > Andi Kleen <[email protected]>
> >
> > PR gcov-profile/118442
> > * profile.cc (branch_prob): Ignore EDGE_FAKE edges from musttail calls
> > to EXIT.
> >
> > * c-c++-common/pr118442.c: New test.
> >
> > --- gcc/profile.cc.jj 2025-01-02 11:23:16.458517673 +0100
> > +++ gcc/profile.cc 2025-03-25 09:57:21.860398601 +0100
> > @@ -1340,6 +1340,20 @@ branch_prob (bool thunk)
> > EDGE_INFO (e)->ignore = 1;
> > ignored_edges++;
> > }
> > + /* Ignore fake edges after musttail calls. */
> > + if ((e->flags & EDGE_FAKE)
> > + && e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun))
> > + {
> > + gimple_stmt_iterator gsi = gsi_last_bb (e->src);
>
> At least the musttail pass allows some statements after the call, like labels
> and debug information. Not sure if it matters.
I think it shouldn't.
gimple_flow_call_edges_add splits basic blocks with calls after those calls
and adds the EDGE_FAKE edges to EXIT, so the last stmt at the end of
the bb from which the edge goes should be the call.
Jakub
