[gcc(refs/users/hubicka/heads/honza-gcc-benchmark-branch-v2)] Add early loop unrolling.

[Jan Hubicka <hubicka@gcc.gnu.org>]

https://gcc.gnu.org/g:6edc7d3ba0654401089a627b9272952f66cd659f

commit 6edc7d3ba0654401089a627b9272952f66cd659f
Author: Jan Hubicka <jh@suse.cz>
Date:   Thu Oct 7 12:10:56 2021 +0200

    Add early loop unrolling.

Diff:
---
 gcc/ipa-modref-tree.h       |  7 +++++-
 gcc/opts.c                  |  1 +
 gcc/passes.def              |  1 +
 gcc/tree-pass.h             |  1 +
 gcc/tree-ssa-loop-ivcanon.c | 57 +++++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 66 insertions(+), 1 deletion(-)

diff --git a/gcc/ipa-modref-tree.h b/gcc/ipa-modref-tree.h
index 6a9ed5ce54b..f3f6e123d67 100644
--- a/gcc/ipa-modref-tree.h
+++ b/gcc/ipa-modref-tree.h
@@ -616,7 +616,12 @@ private:
 
 	  if (n->contains (*a))
 	    found = true;
-	  if (!found && n->merge (*a, false))
+	  else if (a->contains (n))
+	    {
+	      *n = a;
+	      found = true;
+	    }
+	  else if (n->merge (*a, false))
 	    found = restart = true;
 	  if (found)
 	    {
diff --git a/gcc/opts.c b/gcc/opts.c
index fae3a121146..1d2d22d7a3f 100644
--- a/gcc/opts.c
+++ b/gcc/opts.c
@@ -561,6 +561,7 @@ static const struct default_options default_options_table[] =
     { OPT_LEVELS_1_PLUS, OPT_fforward_propagate, NULL, 1 },
     { OPT_LEVELS_1_PLUS, OPT_fguess_branch_probability, NULL, 1 },
     { OPT_LEVELS_1_PLUS, OPT_fipa_profile, NULL, 1 },
+    { OPT_LEVELS_1_PLUS, OPT_fipa_pure_const, NULL, 1 },
     { OPT_LEVELS_1_PLUS, OPT_fipa_reference, NULL, 1 },
     { OPT_LEVELS_1_PLUS, OPT_fipa_reference_addressable, NULL, 1 },
     { OPT_LEVELS_1_PLUS, OPT_fmerge_constants, NULL, 1 },
diff --git a/gcc/passes.def b/gcc/passes.def
index d7a1f8c97a6..64b4b7ec45f 100644
--- a/gcc/passes.def
+++ b/gcc/passes.def
@@ -83,6 +83,7 @@ along with GCC; see the file COPYING3.  If not see
 	  NEXT_PASS (pass_forwprop);
           NEXT_PASS (pass_early_thread_jumps);
 	  NEXT_PASS (pass_sra_early);
+          NEXT_PASS (pass_early_complete_unrolli);
 	  /* pass_build_ealias is a dummy pass that ensures that we
 	     execute TODO_rebuild_alias at this point.  */
 	  NEXT_PASS (pass_build_ealias);
diff --git a/gcc/tree-pass.h b/gcc/tree-pass.h
index eb75eb17951..a3959322b29 100644
--- a/gcc/tree-pass.h
+++ b/gcc/tree-pass.h
@@ -389,6 +389,7 @@ extern gimple_opt_pass *make_pass_simduid_cleanup (gcc::context *ctxt);
 extern gimple_opt_pass *make_pass_slp_vectorize (gcc::context *ctxt);
 extern gimple_opt_pass *make_pass_complete_unroll (gcc::context *ctxt);
 extern gimple_opt_pass *make_pass_complete_unrolli (gcc::context *ctxt);
+extern gimple_opt_pass *make_pass_early_complete_unrolli (gcc::context *ctxt);
 extern gimple_opt_pass *make_pass_pre_slp_scalar_cleanup (gcc::context *ctxt);
 extern gimple_opt_pass *make_pass_parallelize_loops (gcc::context *ctxt);
 extern gimple_opt_pass *make_pass_loop_prefetch (gcc::context *ctxt);
diff --git a/gcc/tree-ssa-loop-ivcanon.c b/gcc/tree-ssa-loop-ivcanon.c
index 8d8791f837e..84c79e84ad8 100644
--- a/gcc/tree-ssa-loop-ivcanon.c
+++ b/gcc/tree-ssa-loop-ivcanon.c
@@ -1673,3 +1673,60 @@ make_pass_complete_unrolli (gcc::context *ctxt)
 }
 
 
+
+/* Complete unrolling of inner loops.  */
+
+namespace {
+
+const pass_data pass_data_early_complete_unrolli =
+{
+  GIMPLE_PASS, /* type */
+  "early-cunrolli", /* name */
+  OPTGROUP_LOOP, /* optinfo_flags */
+  TV_COMPLETE_UNROLL, /* tv_id */
+  ( PROP_cfg | PROP_ssa ), /* properties_required */
+  0, /* properties_provided */
+  0, /* properties_destroyed */
+  0, /* todo_flags_start */
+  0, /* todo_flags_finish */
+};
+
+class pass_early_complete_unrolli : public gimple_opt_pass
+{
+public:
+  pass_early_complete_unrolli (gcc::context *ctxt)
+    : gimple_opt_pass (pass_data_early_complete_unrolli, ctxt)
+  {}
+
+  /* opt_pass methods: */
+  virtual bool gate (function *) { return optimize >= 2; }
+  virtual unsigned int execute (function *);
+
+}; // class pass_early_complete_unrolli
+
+unsigned int
+pass_early_complete_unrolli::execute (function *fun)
+{
+  unsigned ret = 0;
+
+  loop_optimizer_init (LOOPS_NORMAL | LOOPS_HAVE_RECORDED_EXITS);
+  if (number_of_loops (fun) > 1)
+    {
+      scev_initialize ();
+      ret = tree_unroll_loops_completely (false, false);
+      scev_finalize ();
+    }
+  loop_optimizer_finalize ();
+
+  return ret;
+}
+
+} // anon namespace
+
+gimple_opt_pass *
+make_pass_early_complete_unrolli (gcc::context *ctxt)
+{
+  return new pass_early_complete_unrolli (ctxt);
+}
+
+