re PR ipa/68148 (Devirtualization only applies to last of multiple successive calls)

	PR ipa/68148
	* ipa-icf.c (sem_function::merge): Virtual functions may become
	reachable even if they address is not taken and there are no
	idrect calls.
	* g++.dg/ipa/devirt-49.C: New testcase.

From-SVN: r232410

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 006493bb4b077c734b146920b38c3e261deaae15..ac14805ae7625efeffb87961e624893982beca49 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,10 @@
+2016-01-15  Jan Hubicka  <hubicka@ucw.cz>
+
+       PR ipa/68148
+       * ipa-icf.c (sem_function::merge): Virtual functions may become
+       reachable even if they address is not taken and there are no
+       idrect calls.
+
 2016-01-15  Jan Hubicka  <hubicka@ucw.cz>
 
        * lto-streamer-out.c (subtract_estimated_size): New function.

diff --git a/gcc/ipa-icf.c b/gcc/ipa-icf.c
index aaa6a4766c9510cd2b93f38e51029d2fc2e2c0f1..ef04c559bf406636dc34569cf0ba384b572a74d8 100644 (file)
--- a/gcc/ipa-icf.c
+++ b/gcc/ipa-icf.c
@@ -1305,6 +1305,7 @@ sem_function::merge (sem_item *alias_item)
 
       /* If all callers was redirected, do not produce wrapper.  */
       if (alias->can_remove_if_no_direct_calls_p ()
+         && !DECL_VIRTUAL_P (alias->decl)
          && !alias->has_aliases_p ())
        {
          create_wrapper = false;

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index e50e1f936e1b4e77cdedce2d4890a18edf7a08f5..409c42f01720485be973b0a144c2d32b9328dd3e 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2016-01-15  Jan Hubicka <hubicka@ucw.cz>
+
+       PR ipa/68148
+       * g++.dg/ipa/devirt-49.C: New testcase.
+
 2016-01-15  Christian Bruel  <christian.bruel@st.com>
 
        PR target/65837

diff --git a/gcc/testsuite/g++.dg/ipa/devirt-49.C b/gcc/testsuite/g++.dg/ipa/devirt-49.C
new file mode 100644 (file)
index 0000000..6beb47b
--- /dev/null
+++ b/gcc/testsuite/g++.dg/ipa/devirt-49.C
@@ -0,0 +1,20 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-ipa-devirt"  } */
+struct Interface {
+  virtual ~Interface() {}
+  virtual void virtualFunc() = 0;
+  virtual void virtualFunc2() = 0;
+};
+
+struct Concrete : Interface {
+  int counter_;
+  Concrete() : counter_(0) {}
+  void virtualFunc() { counter_++; }
+  void virtualFunc2() { counter_++; }
+};
+
+void test(Interface &c) {
+  c.virtualFunc();
+  c.virtualFunc2();
+}
+/* { dg-final { scan-ipa-dump "2 speculatively devirtualized" "devirt"  } } */