[patch,openacc] Fix PR71959: lto dump of callee counts

[Cesar Philippidis <cesar at codesourcery dot com>]

This is another old gomp4 patch that demotes an ICE in PR71959 to a
linker warning. One problem here is that it is not clear if OpenACC
allows individual member functions in C++ classes to be marked as acc
routines. There's another issue accessing member data inside offloaded
regions. We'll add some support for member data OpenACC 2.6, but some of
the OpenACC C++ semantics are still unclear.

Is this OK for trunk? I bootstrapped and regtested it for x86_64 Linux
with nvptx offloading.

Thanks,
Cesar

[PR71959] lto dump of callee counts

2018-XX-YY  Nathan Sidwell  <nathan@acm.org>
	    Cesar Philippidis  <cesar@codesourcery.com>

	gcc/
	* ipa-inline-analysis.c (inline_write_summary): Only dump callee
	counts when dumping the function's body.

	libgomp/
	* testsuite/libgomp.oacc-c++/pr71959.C: New.
	* testsuite/libgomp.oacc-c++/pr71959-a.C: New.

(cherry picked from gomp-4_0-branch r239788)
---
 gcc/ipa-fnsummary.c                           | 18 ++++++++---
 .../testsuite/libgomp.oacc-c++/pr71959-a.C    | 31 +++++++++++++++++++
 libgomp/testsuite/libgomp.oacc-c++/pr71959.C  | 31 +++++++++++++++++++
 3 files changed, 75 insertions(+), 5 deletions(-)
 create mode 100644 libgomp/testsuite/libgomp.oacc-c++/pr71959-a.C
 create mode 100644 libgomp/testsuite/libgomp.oacc-c++/pr71959.C

diff --git a/gcc/ipa-fnsummary.c b/gcc/ipa-fnsummary.c
index 62095c6cf6f..e796b085e14 100644
--- a/gcc/ipa-fnsummary.c
+++ b/gcc/ipa-fnsummary.c
@@ -3409,8 +3409,10 @@ ipa_fn_summary_write (void)
 	  int i;
 	  size_time_entry *e;
 	  struct condition *c;
+	  int index = lto_symtab_encoder_encode (encoder, cnode);
+	  bool body = encoder->nodes[index].body;
 
-	  streamer_write_uhwi (ob, lto_symtab_encoder_encode (encoder, cnode));
+	  streamer_write_uhwi (ob, index);
 	  streamer_write_hwi (ob, info->estimated_self_stack_size);
 	  streamer_write_hwi (ob, info->self_size);
 	  info->time.stream_out (ob);
@@ -3453,10 +3455,16 @@ ipa_fn_summary_write (void)
 	    info->array_index->stream_out (ob);
 	  else
 	    streamer_write_uhwi (ob, 0);
-	  for (edge = cnode->callees; edge; edge = edge->next_callee)
-	    write_ipa_call_summary (ob, edge);
-	  for (edge = cnode->indirect_calls; edge; edge = edge->next_callee)
-	    write_ipa_call_summary (ob, edge);
+	  if (body)
+	    {
+	      /* Only write callee counts when we're emitting the
+		 body, as the reader only knows about the callees when
+		 the body's emitted.  */
+	      for (edge = cnode->callees; edge; edge = edge->next_callee)
+		write_ipa_call_summary (ob, edge);
+	      for (edge = cnode->indirect_calls; edge; edge = edge->next_callee)
+		write_ipa_call_summary (ob, edge);
+	    }
 	}
     }
   streamer_write_char_stream (ob->main_stream, 0);
diff --git a/libgomp/testsuite/libgomp.oacc-c++/pr71959-a.C b/libgomp/testsuite/libgomp.oacc-c++/pr71959-a.C
new file mode 100644
index 00000000000..9486512d0e7
--- /dev/null
+++ b/libgomp/testsuite/libgomp.oacc-c++/pr71959-a.C
@@ -0,0 +1,31 @@
+// { dg-do compile }
+
+struct Iter 
+{
+  int *cursor;
+
+  void ctor (int *cursor_) asm("_ZN4IterC1EPi");
+  int *point () const asm("_ZNK4Iter5pointEv");
+};
+
+#pragma acc routine
+void  Iter::ctor (int *cursor_)
+{
+  cursor = cursor_;
+}
+
+#pragma acc routine
+int *Iter::point () const
+{
+  return cursor;
+}
+
+void apply (int (*fn)(), Iter out) asm ("_ZN5Apply5applyEPFivE4Iter");
+
+#pragma acc routine
+void apply (int (*fn)(), struct Iter out)
+{ *out.point() = fn (); }
+
+extern "C" void __gxx_personality_v0 ()
+{
+}
diff --git a/libgomp/testsuite/libgomp.oacc-c++/pr71959.C b/libgomp/testsuite/libgomp.oacc-c++/pr71959.C
new file mode 100644
index 00000000000..169bf4aad17
--- /dev/null
+++ b/libgomp/testsuite/libgomp.oacc-c++/pr71959.C
@@ -0,0 +1,31 @@
+// { dg-additional-sources "pr71959-a.C" }
+
+// pr lto/71959 ICEd LTO due to mismatch between writing & reading behaviour
+
+struct Iter
+{
+  int *cursor;
+  
+  Iter(int *cursor_) : cursor(cursor_) {}
+
+  int *point() const { return cursor; }
+};
+
+#pragma acc routine seq
+int one () { return 1; }
+
+struct Apply
+{
+  static void apply (int (*fn)(), Iter out)
+  { *out.point() = fn (); }
+};
+
+int main ()
+{
+  int x;
+  
+#pragma acc parallel copyout(x)
+  Apply::apply (one, Iter (&x));
+
+  return x != 1;
+}
-- 
2.17.1