Hi,
This patch fixes problem in profile_count::to_sreal_scale. We our porfile
counters can be function local, global (ipa) or function local but globally 0.
The last is used to hold static estimates for functions executed 0 times in
profile. Now only one 64bit value is stored and if we compute frequency
of global0 counter in global counter we mix them up and return non-zero value
incorrectly.
I also implemented unit test, but will commit sanity checking separately from
fixes: there are multiple bugs in this area I tracked down.
Bootstrapped/regtested x86_64-linux, comitted.
Honza
* profile-count.c (profile_count::to_sreal_scale): Handle correctly
combination of globa0 and global counters..
Index: profile-count.c
===================================================================
--- profile-count.c (revision 278681)
+++ profile-count.c (working copy)
@@ -310,6 +311,20 @@ profile_count::to_sreal_scale (profile_c
}
if (known)
*known = true;
+ /* Watch for cases where one count is IPA and other is not. */
+ if (in.ipa ().initialized_p ())
+ {
+ gcc_checking_assert (ipa ().initialized_p ());
+ /* If current count is inter-procedurally 0 and IN is inter-procedurally
+ non-zero, return 0. */
+ if (in.ipa ().nonzero_p ()
+ && !ipa().nonzero_p ())
+ return 0;
+ }
+ else
+ /* We can handle correctly 0 IPA count within locally estimated
+ profile, but otherwise we are lost and this should not happen. */
+ gcc_checking_assert (!ipa ().initialized_p () || !ipa ().nonzero_p ());
if (*this == zero ())
return 0;
if (m_val == in.m_val)
