[v3,5/8] Add a bit more logging scheduler's dependency analysis

Message ID 20231122111415.815147-6-maxim.kuvyrkov@linaro.org
State New
Headers
Series Avoid exponential behavior in scheduler and better logging |

Commit Message

Maxim Kuvyrkov Nov. 22, 2023, 11:14 a.m. UTC
  gcc/ChangeLog:

	* sched-deps.cc (sd_add_dep, find_inc): Add logging about
	dependency creation.
---
 gcc/sched-deps.cc | 30 ++++++++++++++++++++++++++----
 1 file changed, 26 insertions(+), 4 deletions(-)
  

Comments

Maxim Kuvyrkov Jan. 15, 2024, 1:04 p.m. UTC | #1
Dear scheduler maintainers,

Gentle ping.  This is a trivial patch, which makes debugging sched-deps.cc
slightly more enjoyable.

On Wed, 22 Nov 2023 at 15:14, Maxim Kuvyrkov <maxim.kuvyrkov@linaro.org>
wrote:

> gcc/ChangeLog:
>
>         * sched-deps.cc (sd_add_dep, find_inc): Add logging about
>         dependency creation.
> ---
>  gcc/sched-deps.cc | 30 ++++++++++++++++++++++++++----
>  1 file changed, 26 insertions(+), 4 deletions(-)
>
> diff --git a/gcc/sched-deps.cc b/gcc/sched-deps.cc
> index 4d357079a7a..2a87158ba4b 100644
> --- a/gcc/sched-deps.cc
> +++ b/gcc/sched-deps.cc
> @@ -1342,6 +1342,13 @@ sd_add_dep (dep_t dep, bool resolved_p)
>       in the bitmap caches of dependency information.  */
>    if (true_dependency_cache != NULL)
>      set_dependency_caches (dep);
> +
> +  if (sched_verbose >= 9)
> +    {
> +      fprintf (sched_dump, "created dependency ");
> +      dump_dep (sched_dump, dep, 1);
> +      fprintf (sched_dump, "\n");
> +    }
>  }
>
>  /* Add or update backward dependence between INSN and ELEM
> @@ -4879,18 +4886,33 @@ find_inc (struct mem_inc_info *mii, bool backwards)
>              we create.  */
>           gcc_assert (mii->inc_insn == inc_cand);
>
> +         int n_deps_created = 0;
>           if (backwards)
>             {
>               FOR_EACH_DEP (mii->inc_insn, SD_LIST_BACK, sd_it, dep)
> -               add_dependence_1 (mii->mem_insn, DEP_PRO (dep),
> -                                 REG_DEP_TRUE);
> +               {
> +                 add_dependence_1 (mii->mem_insn, DEP_PRO (dep),
> +                                   REG_DEP_TRUE);
> +                 ++n_deps_created;
> +               }
>             }
>           else
>             {
>               FOR_EACH_DEP (mii->inc_insn, SD_LIST_FORW, sd_it, dep)
> -               add_dependence_1 (DEP_CON (dep), mii->mem_insn,
> -                                 REG_DEP_ANTI);
> +               {
> +                 add_dependence_1 (DEP_CON (dep), mii->mem_insn,
> +                                   REG_DEP_ANTI);
> +                 ++n_deps_created;
> +               }
>             }
> +         if (sched_verbose >= 6)
> +           fprintf (sched_dump,
> +                    "created %d deps for mem_insn %d due to "
> +                    "inc_insn %d %s deps\n",
> +                    n_deps_created, INSN_UID (mii->mem_insn),
> +                    INSN_UID (mii->inc_insn),
> +                    backwards ? "backward" : "forward");
> +
>           return true;
>         }
>      next:
> --
> 2.34.1
>
>
  

Patch

diff --git a/gcc/sched-deps.cc b/gcc/sched-deps.cc
index 4d357079a7a..2a87158ba4b 100644
--- a/gcc/sched-deps.cc
+++ b/gcc/sched-deps.cc
@@ -1342,6 +1342,13 @@  sd_add_dep (dep_t dep, bool resolved_p)
      in the bitmap caches of dependency information.  */
   if (true_dependency_cache != NULL)
     set_dependency_caches (dep);
+
+  if (sched_verbose >= 9)
+    {
+      fprintf (sched_dump, "created dependency ");
+      dump_dep (sched_dump, dep, 1);
+      fprintf (sched_dump, "\n");
+    }
 }
 
 /* Add or update backward dependence between INSN and ELEM
@@ -4879,18 +4886,33 @@  find_inc (struct mem_inc_info *mii, bool backwards)
 	     we create.  */
 	  gcc_assert (mii->inc_insn == inc_cand);
 
+	  int n_deps_created = 0;
 	  if (backwards)
 	    {
 	      FOR_EACH_DEP (mii->inc_insn, SD_LIST_BACK, sd_it, dep)
-		add_dependence_1 (mii->mem_insn, DEP_PRO (dep),
-				  REG_DEP_TRUE);
+		{
+		  add_dependence_1 (mii->mem_insn, DEP_PRO (dep),
+				    REG_DEP_TRUE);
+		  ++n_deps_created;
+		}
 	    }
 	  else
 	    {
 	      FOR_EACH_DEP (mii->inc_insn, SD_LIST_FORW, sd_it, dep)
-		add_dependence_1 (DEP_CON (dep), mii->mem_insn,
-				  REG_DEP_ANTI);
+		{
+		  add_dependence_1 (DEP_CON (dep), mii->mem_insn,
+				    REG_DEP_ANTI);
+		  ++n_deps_created;
+		}
 	    }
+	  if (sched_verbose >= 6)
+	    fprintf (sched_dump,
+		     "created %d deps for mem_insn %d due to "
+		     "inc_insn %d %s deps\n",
+		     n_deps_created, INSN_UID (mii->mem_insn),
+		     INSN_UID (mii->inc_insn),
+		     backwards ? "backward" : "forward");
+
 	  return true;
 	}
     next: