re PR c++/67184 (Missed optimization with C++11 final specifier)

/cp
2019-05-21  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/67184
	PR c++/69445
	* call.c (build_over_call): Devirtualize when the final overrider
	comes from the base.

/testsuite
2019-05-21  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/67184
	PR c++/69445
	* g++.dg/other/final3.C: New.
	* g++.dg/other/final4.C: Likewise.
	* g++.dg/other/final5.C: Likewise.

From-SVN: r271490

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 972bc36c0bed94c0be5f8b757afe6e00bd260486..e26cb9856ff3e7a2affb54a97ff9d28491fc810c 100644 (file)
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,10 @@
+2019-05-21  Paolo Carlini  <paolo.carlini@oracle.com>
+
+       PR c++/67184
+       PR c++/69445
+       * call.c (build_over_call): Devirtualize when the final overrider
+       comes from the base.
+
 2019-05-21  Nathan Sidwell  <nathan@acm.org>
 
        * name-lookup.c (do_nonmember_using_decl): Drop INSERT_P

diff --git a/gcc/cp/call.c b/gcc/cp/call.c
index e160dd160eabfc99b258322c21c53800477541a8..1e167851872906381e44c7b3333077c6db5eb663 100644 (file)
--- a/gcc/cp/call.c
+++ b/gcc/cp/call.c
@@ -8244,7 +8244,7 @@ build_over_call (struct z_candidate *cand, int flags, tsubst_flags_t complain)
       /* See if the function member or the whole class type is declared
         final and the call can be devirtualized.  */
       if (DECL_FINAL_P (fn)
-         || CLASSTYPE_FINAL (TYPE_METHOD_BASETYPE (TREE_TYPE (fn))))
+         || CLASSTYPE_FINAL (TREE_TYPE (argtype)))
        flags |= LOOKUP_NONVIRTUAL;
 
       /* [class.mfct.nonstatic]: If a nonstatic member function of a class

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 2a4cd7fe4714e0f69608372a050b053969253ad0..8c3e8a4488adf6954c4b33f67b354861a98542cb 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,11 @@
+2019-05-21  Paolo Carlini  <paolo.carlini@oracle.com>
+
+       PR c++/67184
+       PR c++/69445
+       * g++.dg/other/final3.C: New.
+       * g++.dg/other/final4.C: Likewise.
+       * g++.dg/other/final5.C: Likewise.
+
 2019-05-21  Marek Polacek  <polacek@redhat.com>
 
        DR 1940 - static_assert in anonymous unions.

diff --git a/gcc/testsuite/g++.dg/other/final3.C b/gcc/testsuite/g++.dg/other/final3.C
new file mode 100644 (file)
index 0000000..a49dc22
--- /dev/null
+++ b/gcc/testsuite/g++.dg/other/final3.C
@@ -0,0 +1,28 @@
+// PR c++/67184
+// { dg-do compile { target c++11 } }
+// { dg-options "-fdump-tree-original"  }
+
+struct V {
+ virtual void foo(); 
+};
+
+struct wV final : V {
+};
+
+struct oV final : V {
+  void foo();
+};
+
+void call(wV& x)
+{
+  x.foo();
+  x.V::foo();
+}
+
+void call(oV& x)
+{
+  x.foo();
+  x.V::foo();
+}
+
+// { dg-final { scan-tree-dump-times "OBJ_TYPE_REF" 0 "original" } }

diff --git a/gcc/testsuite/g++.dg/other/final4.C b/gcc/testsuite/g++.dg/other/final4.C
new file mode 100644 (file)
index 0000000..867ef38
--- /dev/null
+++ b/gcc/testsuite/g++.dg/other/final4.C
@@ -0,0 +1,16 @@
+// PR c++/67184
+// { dg-do compile { target c++11 } }
+// { dg-options "-fdump-tree-original"  }
+
+struct B
+{
+  virtual void operator()();
+  virtual operator int();
+  virtual int operator++();
+};
+
+struct D final : B { };
+
+void foo(D& d) { d(); int t = d; ++d; }
+
+// { dg-final { scan-tree-dump-times "OBJ_TYPE_REF" 0 "original" } }