This patch addresses the bogus "Invocation mismatch" messages seen in parallel profiledbootstrap builds of gcc.

This patch addresses the bogus "Invocation mismatch" messages seen in parallel
profiledbootstrap builds of gcc. See PR bootstrap/55051 for a discussion of
why this is occurring and why this checking is inaccurate. Leave it in when
!GCOV_LOCKED, to warn about concurrent update issues requiring locking.

2012-11-18  Teresa Johnson  <tejohnson@google.com>

	PR bootstrap/55051
	* libgcov.c (gcov_exit): Remove merged program summary
	comparison unless !GCOV_LOCKED.

From-SVN: r193612

1 files changed, 27 insertions, 10 deletions

diff --git a/libgcc/libgcov.c b/libgcc/libgcov.c
index c58427e..ba27c53 100644
--- a/libgcc/libgcov.c
+++ b/libgcc/libgcov.c
@@ -365,7 +365,9 @@ gcov_exit (void)
   struct gcov_info *gi_ptr;
   const struct gcov_fn_info *gfi_ptr;
   struct gcov_summary this_prg; /* summary for program.  */
+#if !GCOV_LOCKED
   struct gcov_summary all_prg;  /* summary for all instances of program.  */
+#endif
   struct gcov_ctr_summary *cs_ptr;
   const struct gcov_ctr_info *ci_ptr;
   unsigned t_ix;
@@ -382,7 +384,9 @@ gcov_exit (void)
   if (gcov_dump_complete)
     return;
 
+#if !GCOV_LOCKED
   memset (&all_prg, 0, sizeof (all_prg));
+#endif
   /* Find the totals for this execution.  */
   memset (&this_prg, 0, sizeof (this_prg));
   for (gi_ptr = gcov_list; gi_ptr; gi_ptr = gi_ptr->next)
@@ -469,7 +473,10 @@ gcov_exit (void)
       unsigned n_counts;
       struct gcov_summary prg; /* summary for this object over all
 				  program.  */
-      struct gcov_ctr_summary *cs_prg, *cs_tprg, *cs_all;
+      struct gcov_ctr_summary *cs_prg, *cs_tprg;
+#if !GCOV_LOCKED
+      struct gcov_ctr_summary *cs_all;
+#endif
       int error = 0;
       gcov_unsigned_t tag, length;
       gcov_position_t summary_pos = 0;
@@ -684,7 +691,6 @@ gcov_exit (void)
 	{
 	  cs_prg = &prg.ctrs[t_ix];
 	  cs_tprg = &this_prg.ctrs[t_ix];
-	  cs_all = &all_prg.ctrs[t_ix];
 
 	  if (gi_ptr->merge[t_ix])
 	    {
@@ -703,23 +709,34 @@ gcov_exit (void)
 	  else if (cs_prg->runs)
 	    goto read_mismatch;
 
+#if !GCOV_LOCKED
+	  cs_all = &all_prg.ctrs[t_ix];
 	  if (!cs_all->runs && cs_prg->runs)
-	    memcpy (cs_all, cs_prg, sizeof (*cs_all));
+            {
+              cs_all->num = cs_prg->num;
+              cs_all->runs = cs_prg->runs;
+              cs_all->sum_all = cs_prg->sum_all;
+              cs_all->run_max = cs_prg->run_max;
+              cs_all->sum_max = cs_prg->sum_max;
+            }
 	  else if (!all_prg.checksum
-		   && (!GCOV_LOCKED || cs_all->runs == cs_prg->runs)
                    /* Don't compare the histograms, which may have slight
                       variations depending on the order they were updated
                       due to the truncating integer divides used in the
                       merge.  */
-                   && memcmp (cs_all, cs_prg,
-                              sizeof (*cs_all) - (sizeof (gcov_bucket_type)
-                                                  * GCOV_HISTOGRAM_SIZE)))
+                   && (cs_all->num != cs_prg->num
+                       || cs_all->runs != cs_prg->runs
+                       || cs_all->sum_all != cs_prg->sum_all
+                       || cs_all->run_max != cs_prg->run_max
+                       || cs_all->sum_max != cs_prg->sum_max))
 	    {
-	      fprintf (stderr, "profiling:%s:Invocation mismatch - some data files may have been removed%s\n",
-		       gi_filename, GCOV_LOCKED
-		       ? "" : " or concurrently updated without locking support");
+	      fprintf (stderr,
+                       "profiling:%s:Data file mismatch - some data files may "
+                       "have been concurrently updated without locking support\n",
+		       gi_filename);
 	      all_prg.checksum = ~0u;
 	    }
+#endif
 	}
 
       prg.checksum = crc32;