Jakub Jelinek <ja...@redhat.com> wrote:
>Hi!
>
>On the following testcase we ICE because the builtin fn prototype
>doesn't
>have throw () on it (glibc headers provide it, but some other C
>libraries
>apparently don't) and thus we can have EH edges out of the builtin, and
>call-cdce unconditionally split the block, leaving EH edge from an
>empty
>bb and the required EH edge missing from the call.
>
>In that case there is no point in splitting the block though, so fixed
>thusly (not looking for last stmt, because that might be problematic
>with
>-fcompare-debug).
>
>Bootstrapped/regtested on x86_64-linux and i686-linux, ok for
>trunk/4.8?
>
Ok,.
Thanks,
Richard.
>2013-08-15 Jakub Jelinek <ja...@redhat.com>
>
> PR tree-optimization/58165
> * tree-call-cdce.c (shrink_wrap_one_built_in_call): If
> bi_call must be the last stmt in a bb, don't split_block, instead
> use fallthru edge from it and give up if there is none.
> Release conds vector when returning early.
>
> * g++.dg/opt/pr58165.C: New test.
>
>--- gcc/tree-call-cdce.c.jj 2013-08-13 12:20:33.000000000 +0200
>+++ gcc/tree-call-cdce.c 2013-08-15 14:54:28.328435719 +0200
>@@ -726,15 +726,28 @@ shrink_wrap_one_built_in_call (gimple bi
> return false and do not do any transformation for
> the call. */
> if (nconds == 0)
>- return false;
>+ {
>+ conds.release ();
>+ return false;
>+ }
>
> bi_call_bb = gimple_bb (bi_call);
>
>- /* Now find the join target bb -- split
>- bi_call_bb if needed. */
>- bi_call_bsi = gsi_for_stmt (bi_call);
>+ /* Now find the join target bb -- split bi_call_bb if needed. */
>+ if (stmt_ends_bb_p (bi_call))
>+ {
>+ /* If the call must be the last in the bb, don't split the
>block,
>+ it could e.g. have EH edges. */
>+ join_tgt_in_edge_from_call = find_fallthru_edge
>(bi_call_bb->succs);
>+ if (join_tgt_in_edge_from_call == NULL)
>+ {
>+ conds.release ();
>+ return false;
>+ }
>+ }
>+ else
>+ join_tgt_in_edge_from_call = split_block (bi_call_bb, bi_call);
>
>- join_tgt_in_edge_from_call = split_block (bi_call_bb, bi_call);
> bi_call_bsi = gsi_for_stmt (bi_call);
>
> join_tgt_bb = join_tgt_in_edge_from_call->dest;
>--- gcc/testsuite/g++.dg/opt/pr58165.C.jj 2013-08-15 14:39:20.492586499
>+0200
>+++ gcc/testsuite/g++.dg/opt/pr58165.C 2013-08-15 14:38:43.000000000
>+0200
>@@ -0,0 +1,14 @@
>+// PR tree-optimization/58165
>+// { dg-do compile }
>+// { dg-options "-O2" }
>+
>+extern "C" float sqrtf (float);
>+
>+struct A { A (); ~A (); };
>+
>+void
>+foo (double d)
>+{
>+ A a;
>+ sqrtf (d);
>+}
>
> Jakub
