Hi,
As Richi suggested in PR100794, this patch is to remove
some unnecessary update_ssa calls with flag
TODO_update_ssa_only_virtuals, also do some refactoring.
Bootstrapped/regtested on powerpc64le-linux-gnu P9,
x86_64-redhat-linux and aarch64-linux-gnu, built well
on Power9 ppc64le with --with-build-config=bootstrap-O3,
and passed both P8 and P9 SPEC2017 full build with
{-O3, -Ofast} + {,-funroll-loops}.
Is it ok for trunk?
BR,
Kewen
-----
gcc/ChangeLog:
* tree-predcom.c (execute_pred_commoning): Remove update_ssa call.
(tree_predictive_commoning_loop): Factor some cleanup stuffs into
lambda function cleanup, remove scev_reset call, and adjust return
value.
(tree_predictive_commoning): Adjust for different changed values,
only set flag TODO_update_ssa_only_virtuals if changed.
(pass_data pass_data_predcom): Remove TODO_update_ssa_only_virtuals
from todo_flags_finish.
gcc/tree-predcom.c | 50 ++++++++++++++++++++++++++--------------------
1 file changed, 28 insertions(+), 22 deletions(-)
diff --git a/gcc/tree-predcom.c b/gcc/tree-predcom.c
index 5482f50198a..02f911a08bb 100644
--- a/gcc/tree-predcom.c
+++ b/gcc/tree-predcom.c
@@ -2280,8 +2280,6 @@ execute_pred_commoning (class loop *loop, vec<chain_p>
chains,
remove_stmt (a->stmt);
}
}
-
- update_ssa (TODO_update_ssa_only_virtuals);
}
/* For each reference in CHAINS, if its defining statement is
@@ -3174,9 +3172,10 @@ insert_init_seqs (class loop *loop, vec<chain_p> chains)
}
}
-/* Performs predictive commoning for LOOP. Sets bit 1<<0 of return value
- if LOOP was unrolled; Sets bit 1<<1 of return value if loop closed ssa
- form was corrupted. */
+/* Performs predictive commoning for LOOP. Sets bit 1<<1 of return value
+ if LOOP was unrolled; Sets bit 1<<2 of return value if loop closed ssa
+ form was corrupted. Non-zero return value indicates some changes were
+ applied to this loop. */
static unsigned
tree_predictive_commoning_loop (class loop *loop)
@@ -3188,7 +3187,6 @@ tree_predictive_commoning_loop (class loop *loop)
unsigned unroll_factor;
class tree_niter_desc desc;
bool unroll = false, loop_closed_ssa = false;
- edge exit;
if (dump_file && (dump_flags & TDF_DETAILS))
fprintf (dump_file, "Processing loop %d\n", loop->num);
@@ -3244,13 +3242,22 @@ tree_predictive_commoning_loop (class loop *loop)
determine_roots (loop, components, &chains);
release_components (components);
+ auto cleanup = [&]() {
+ release_chains (chains);
+ free_data_refs (datarefs);
+ BITMAP_FREE (looparound_phis);
+ free_affine_expand_cache (&name_expansions);
+ };
+
if (!chains.exists ())
{
if (dump_file && (dump_flags & TDF_DETAILS))
fprintf (dump_file,
"Predictive commoning failed: no suitable chains\n");
- goto end;
+ cleanup ();
+ return 0;
}
+
prepare_initializers (loop, chains);
loop_closed_ssa = prepare_finalizers (loop, chains);
@@ -3268,10 +3275,8 @@ tree_predictive_commoning_loop (class loop *loop)
/* Determine the unroll factor, and if the loop should be unrolled, ensure
that its number of iterations is divisible by the factor. */
unroll_factor = determine_unroll_factor (chains);
- scev_reset ();
unroll = (unroll_factor > 1
&& can_unroll_loop_p (loop, unroll_factor, &desc));
- exit = single_dom_exit (loop);
/* Execute the predictive commoning transformations, and possibly unroll the
loop. */
@@ -3285,8 +3290,6 @@ tree_predictive_commoning_loop (class loop *loop)
dta.chains = chains;
dta.tmp_vars = tmp_vars;
- update_ssa (TODO_update_ssa_only_virtuals);
-
/* Cfg manipulations performed in tree_transform_and_unroll_loop before
execute_pred_commoning_cbck is called may cause phi nodes to be
reallocated, which is a problem since CHAINS may point to these
@@ -3295,6 +3298,7 @@ tree_predictive_commoning_loop (class loop *loop)
the phi nodes in execute_pred_commoning_cbck. A bit hacky. */
replace_phis_by_defined_names (chains);
+ edge exit = single_dom_exit (loop);
tree_transform_and_unroll_loop (loop, unroll_factor, exit, &desc,
execute_pred_commoning_cbck, &dta);
eliminate_temp_copies (loop, tmp_vars);
@@ -3307,14 +3311,9 @@ tree_predictive_commoning_loop (class loop *loop)
execute_pred_commoning (loop, chains, tmp_vars);
}
-end: ;
- release_chains (chains);
- free_data_refs (datarefs);
- BITMAP_FREE (looparound_phis);
+ cleanup ();
- free_affine_expand_cache (&name_expansions);
-
- return (unroll ? 1 : 0) | (loop_closed_ssa ? 2 : 0);
+ return (unroll ? 2 : 1) | (loop_closed_ssa ? 4 : 1);
}
/* Runs predictive commoning. */
@@ -3335,12 +3334,19 @@ tree_predictive_commoning (void)
if (changed > 0)
{
- scev_reset ();
+ ret = TODO_update_ssa_only_virtuals;
+ /* Some loop(s) got unrolled. */
if (changed > 1)
- rewrite_into_loop_closed_ssa (NULL, TODO_update_ssa);
+ {
+ scev_reset ();
- ret = TODO_cleanup_cfg;
+ /* Need to fix up loop closed SSA. */
+ if (changed >= 4)
+ rewrite_into_loop_closed_ssa (NULL, TODO_update_ssa);
+
+ ret |= TODO_cleanup_cfg;
+ }
}
return ret;
@@ -3369,7 +3375,7 @@ const pass_data pass_data_predcom =
0, /* properties_provided */
0, /* properties_destroyed */
0, /* todo_flags_start */
- TODO_update_ssa_only_virtuals, /* todo_flags_finish */
+ 0, /* todo_flags_finish */
};
class pass_predcom : public gimple_opt_pass
--
2.17.1
