[PR,57670] Do not turn member pointers to builtin_unreachable

Index: src/gcc/cgraph.h
===================================================================
--- src.orig/gcc/cgraph.h
+++ src/gcc/cgraph.h
@@ -440,6 +440,8 @@  struct GTY(()) cgraph_indirect_call_info
   /* Set when the call is a call of a pointer loaded from contents of an
      aggregate at offset.  */
   unsigned agg_contents : 1;
+  /* Set when this is a call through a member pointer.  */
+  unsigned member_ptr : 1;
   /* When the previous bit is set, this one determines whether the destination
      is loaded from a parameter passed by reference. */
   unsigned by_ref : 1;
Index: src/gcc/ipa-prop.c
===================================================================
--- src.orig/gcc/ipa-prop.c
+++ src/gcc/ipa-prop.c
@@ -288,8 +288,9 @@  ipa_print_node_jump_functions (FILE *f,
 
       ii = cs->indirect_info;
       if (ii->agg_contents)
-	fprintf (f, "    indirect aggregate callsite, calling param %i, "
+	fprintf (f, "    indirect %s callsite, calling param %i, "
 		 "offset " HOST_WIDE_INT_PRINT_DEC ", %s",
+		 ii->member_ptr ? "member ptr" : "aggregate",
 		 ii->param_index, ii->offset,
 		 ii->by_ref ? "by reference" : "by_value");
       else
@@ -1608,6 +1609,7 @@  ipa_note_param_call (struct cgraph_node
   cs->indirect_info->offset = 0;
   cs->indirect_info->polymorphic = 0;
   cs->indirect_info->agg_contents = 0;
+  cs->indirect_info->member_ptr = 0;
   return cs;
 }
 
@@ -1801,6 +1803,7 @@  ipa_analyze_indirect_call_uses (struct c
       struct cgraph_edge *cs = ipa_note_param_call (node, index, call);
       cs->indirect_info->offset = offset;
       cs->indirect_info->agg_contents = 1;
+      cs->indirect_info->member_ptr = 1;
     }
 
   return;
@@ -2212,6 +2215,10 @@  ipa_make_edge_direct_to_target (struct c
       target = canonicalize_constructor_val (target, NULL);
       if (!target || TREE_CODE (target) != FUNCTION_DECL)
 	{
+	  if (ie->indirect_info->member_ptr)
+	    /* Member pointer call that goes through a VMT lookup.  */
+	    return NULL;
+
 	  if (dump_file)
 	    fprintf (dump_file, "ipa-prop: Discovered direct call to non-function"
 				" in %s/%i, making it unreachable.\n",
@@ -3765,6 +3772,7 @@  ipa_write_indirect_edge_info (struct out
   bp = bitpack_create (ob->main_stream);
   bp_pack_value (&bp, ii->polymorphic, 1);
   bp_pack_value (&bp, ii->agg_contents, 1);
+  bp_pack_value (&bp, ii->member_ptr, 1);
   bp_pack_value (&bp, ii->by_ref, 1);
   streamer_write_bitpack (&bp);
 
@@ -3791,6 +3799,7 @@  ipa_read_indirect_edge_info (struct lto_
   bp = streamer_read_bitpack (ib);
   ii->polymorphic = bp_unpack_value (&bp, 1);
   ii->agg_contents = bp_unpack_value (&bp, 1);
+  ii->member_ptr = bp_unpack_value (&bp, 1);
   ii->by_ref = bp_unpack_value (&bp, 1);
   if (ii->polymorphic)
     {
Index: src/gcc/testsuite/g++.dg/ipa/pr57670.C
===================================================================
--- /dev/null
+++ src/gcc/testsuite/g++.dg/ipa/pr57670.C
@@ -0,0 +1,37 @@ 
+/* { dg-do run } */
+/* { dg-options "-O3 -fno-early-inlining" } */
+
+class H
+{
+public:
+  virtual unsigned bar() const { return 16; }
+};
+
+class A : public H
+{
+  unsigned foo(unsigned (H::*func)(void) const) const;
+public:
+  H *h;
+  virtual unsigned bar() const;
+};
+
+unsigned A::foo(unsigned (H::*func)(void) const) const
+{
+  return  (h->*func)();
+}
+
+unsigned A::bar() const
+{
+  return foo(&H::bar);
+}
+
+int main (int argc, char **argv)
+{
+  H h;
+  A a;
+  a.h = &h;
+
+  if (a.bar() != 16)
+    __builtin_abort ();
+  return 0;
+}