[Bug tree-optimization/106896] [13 Regression] ICE in to_sreal_scale, at profile-count.cc:339 since r13-2288-g61c4c989034548f4

["hubicka at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106896

--- Comment #11 from Jan Hubicka <hubicka at gcc dot gnu.org> ---
Originally to_sreal_frquency was intended to work both inter-procedurally and
intra-procedurally. However in such setup there are side cases that can not be
solved without knowing the corresponding entry_bb_counts which are not known to
the function.
Inspecting existing uses of to_sreal_frequency it is used intra-procedurally
only.  In that case it makes sense to implement it same way as probability_in
which is done by the following patch:

diff --git a/gcc/profile-count.cc b/gcc/profile-count.cc
index d05fef3fb00..16585045f8e 100644
--- a/gcc/profile-count.cc
+++ b/gcc/profile-count.cc
@@ -325,6 +325,13 @@ profile_count::to_cgraph_frequency (profile_count
entry_bb_count) const
 sreal
 profile_count::to_sreal_scale (profile_count in, bool *known) const
 {
+  if (*this == zero ()
+      && !(in == zero ()))
+  {
+    if (known)
+      *known = true;
+    return 0;
+  }
   if (!initialized_p () || !in.initialized_p ())
     {
       if (known)
@@ -333,32 +340,13 @@ profile_count::to_sreal_scale (profile_count in, bool
*known) const
     }
   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)
+  if (*this == in)
     return 1;
   gcc_checking_assert (compatible_p (in));
-
+  if (m_val == in.m_val)
+    return 1;
   if (!in.m_val)
-    {
-      if (!m_val)
-       return 1;
-      return m_val * 4;
-    }
+    return m_val * 4;
   return (sreal)m_val / (sreal)in.m_val;
 }