Initial commit for Europar 2021 GCC version

This was the version of GCC used in the Europar 2021 paper with regard
to GCC paralelism. Future commits are possible, so look in the paper the
commit hash of the version was used.

gcc/cgraphunit.c

@@ -2794,10 +2794,22 @@ maybe_compile_in_parallel (void)
   bool jobserver = false;
   bool job_auto = false;
   int num_jobs = -1;
+  unsigned long long insns = 0;
+  cgraph_node *cnode;
 
   if (!flag_parallel_jobs || !split_outputs)
     return false;
 
+  FOR_EACH_FUNCTION_WITH_GIMPLE_BODY (cnode)
+    {
+      ipa_size_summary *ss = ipa_size_summaries->get (cnode);
+      if (!cnode->inlined_to && ss)
+	insns += ss->size;
+    }
+
+  if (insns < (unsigned long long) param_min_partition_size)
+    return false;
+
   if (!strcmp (flag_parallel_jobs, "auto"))
     {
       jobserver = jobserver_initialize ();

gcc/gcc.c

@@ -3405,14 +3405,7 @@ append_split_outputs (extra_arg_storer *storer,
 	  argv[argc++] = extra_argument;
 	}
 
-      if (have_c)
-	{
-	  argv[argc++] = "-fPIE";
-	  argv[argc++] = "-fPIC";
-	}
-
       argv[argc]   = NULL;
-
       commands[0].argv = argv;
     }
 
@@ -3977,7 +3970,7 @@ execute (void)
   /* FIXME: Interact with GNU Jobserver if necessary.  */
 
   commands_batch = commands;
-  n = flag_parallel_jobs? 1: n_commands;
+  n = n_commands;
 
   for (int i = 0; i < n_commands; i += n)
     {

gcc/ipa-split.c

@@ -1909,8 +1909,12 @@ pass_split_functions::gate (function *)
 {
   /* When doing profile feedback, we want to execute the pass after profiling
      is read.  So disable one in early optimization.  */
-  return (flag_partial_inlining
-	  && !profile_arc_flag && !flag_branch_probabilities);
+
+  /* Disabled due to an issue regarding how the partitioner applier
+     handle clones generated by this pass.  */
+  /*return (flag_partial_inlining
+	  && !profile_arc_flag && !flag_branch_probabilities); */
+  return false;
 }
 
 } // anon namespace
@@ -1968,8 +1972,13 @@ pass_feedback_split_functions::gate (function *)
 {
   /* We don't need to split when profiling at all, we are producing
      lousy code anyway.  */
-  return (flag_partial_inlining
-	  && flag_branch_probabilities);
+
+  /* Disabled due to an issue regarding how the partitioner applier
+     handle clones generated by this pass.  */
+  /* return (flag_partial_inlining
+	  && flag_branch_probabilities); */
+
+  return false;
 }
 
 } // anon namespace