aboutsummaryrefslogtreecommitdiff
path: root/gcc/tree-cfg.cc
diff options
context:
space:
mode:
Diffstat (limited to 'gcc/tree-cfg.cc')
-rw-r--r--gcc/tree-cfg.cc131
1 files changed, 83 insertions, 48 deletions
diff --git a/gcc/tree-cfg.cc b/gcc/tree-cfg.cc
index 938d063..7dad7b4 100644
--- a/gcc/tree-cfg.cc
+++ b/gcc/tree-cfg.cc
@@ -6663,14 +6663,16 @@ add_phi_args_after_copy (basic_block *region_copy, unsigned n_region,
true otherwise.
ELIMINATED_EDGE is an edge that is known to be removed in the dupicated
- region. */
+ region. ORIG_ELIMINATED_EDGES, if non-NULL is set of edges known to be
+ removed from the original region. */
bool
gimple_duplicate_sese_region (edge entry, edge exit,
basic_block *region, unsigned n_region,
basic_block *region_copy,
bool update_dominance,
- edge eliminated_edge)
+ edge eliminated_edge,
+ hash_set <edge> *orig_eliminated_edges)
{
unsigned i;
bool free_region_copy = false, copying_header = false;
@@ -6749,7 +6751,8 @@ gimple_duplicate_sese_region (edge entry, edge exit,
split_edge_bb_loc (entry), update_dominance);
if (total_count.initialized_p () && entry_count.initialized_p ())
{
- if (!eliminated_edge)
+ if (!eliminated_edge
+ && (!orig_eliminated_edges || orig_eliminated_edges->is_empty ()))
{
scale_bbs_frequencies_profile_count (region, n_region,
total_count - entry_count,
@@ -6767,7 +6770,7 @@ gimple_duplicate_sese_region (edge entry, edge exit,
if (cond1) <- this condition will become false
and we update probabilities
goto loop_exit;
- if (cond2)
+ if (cond2) <- this condition is loop invariant
goto loop_exit;
goto loop_header <- this will be redirected to loop.
// region_copy_end
@@ -6778,6 +6781,7 @@ gimple_duplicate_sese_region (edge entry, edge exit,
if (cond1) <- we need to update probabbility here
goto loop_exit;
if (cond2) <- and determine scaling factor here.
+ moreover cond2 is now always true
goto loop_exit;
else
goto loop;
@@ -6787,53 +6791,84 @@ gimple_duplicate_sese_region (edge entry, edge exit,
but only consumer so far is tree-ssa-loop-ch and it uses only this
to handle the common case of peeling headers which have
conditionals known to be always true upon entry. */
- gcc_assert (eliminated_edge->src == region[0]
- && EDGE_COUNT (region[0]->succs) == 2
- && copying_header);
-
- edge e, e_copy, eliminated_edge_copy;
- if (EDGE_SUCC (region[0], 0) == eliminated_edge)
- {
- e = EDGE_SUCC (region[0], 1);
- e_copy = EDGE_SUCC (region_copy[0], 1);
- eliminated_edge_copy = EDGE_SUCC (region_copy[0], 0);
- }
- else
+ gcc_checking_assert (copying_header);
+ for (unsigned int i = 0; i < n_region; i++)
{
- e = EDGE_SUCC (region[0], 0);
- e_copy = EDGE_SUCC (region_copy[0], 0);
- eliminated_edge_copy = EDGE_SUCC (region_copy[0], 1);
- }
- gcc_checking_assert (e != e_copy
- && eliminated_edge_copy != eliminated_edge
- && eliminated_edge_copy->dest
- == eliminated_edge->dest);
-
+ edge exit_e, exit_e_copy, e, e_copy;
+ if (EDGE_COUNT (region[i]->succs) == 1)
+ {
+ region_copy[i]->count = entry_count;
+ region[i]->count -= entry_count;
+ continue;
+ }
- /* Handle first basic block in duplicated region as in the
- non-eliminating case. */
- scale_bbs_frequencies_profile_count (region_copy, n_region,
- entry_count, total_count);
- /* Now update redirecting eliminated edge to the other edge.
- Actual CFG update is done by caller. */
- e_copy->probability = profile_probability::always ();
- eliminated_edge_copy->probability = profile_probability::never ();
- /* Header copying is a special case of jump threading, so use
- common code to update loop body exit condition. */
- update_bb_profile_for_threading (region[0], e_copy->count (), e);
- /* If we duplicated more conditionals first scale the profile of
- rest of the preheader. Then work out the probability of
- entering the loop and scale rest of the loop. */
- if (n_region > 1)
- {
- scale_bbs_frequencies_profile_count (region_copy + 1,
- n_region - 1,
- e_copy->count (),
- region_copy[1]->count);
- scale_bbs_frequencies_profile_count (region + 1, n_region - 1,
- e->count (),
- region[1]->count);
+ gcc_checking_assert (EDGE_COUNT (region[i]->succs) == 2);
+ if (loop_exit_edge_p (region[0]->loop_father,
+ EDGE_SUCC (region[i], 0)))
+ {
+ exit_e = EDGE_SUCC (region[i], 0);
+ exit_e_copy = EDGE_SUCC (region_copy[i], 0);
+ e = EDGE_SUCC (region[i], 1);
+ e_copy = EDGE_SUCC (region_copy[i], 1);
+ }
+ else
+ {
+ exit_e = EDGE_SUCC (region[i], 1);
+ exit_e_copy = EDGE_SUCC (region_copy[i], 1);
+ e = EDGE_SUCC (region[i], 0);
+ e_copy = EDGE_SUCC (region_copy[i], 0);
+ }
+ gcc_assert (i == n_region - 1
+ || (e->dest == region[i + 1]
+ && e_copy->dest == region_copy[i + 1]));
+ region_copy[i]->count = entry_count;
+ profile_count exit_e_count = exit_e->count ();
+ if (eliminated_edge == exit_e)
+ {
+ /* Update profile and the conditional.
+ CFG update is done by caller. */
+ e_copy->probability = profile_probability::always ();
+ exit_e_copy->probability = profile_probability::never ();
+ gcond *cond_stmt
+ = as_a <gcond *>(*gsi_last_bb (region_copy[i]));
+ if (e_copy->flags & EDGE_TRUE_VALUE)
+ gimple_cond_make_true (cond_stmt);
+ else
+ gimple_cond_make_false (cond_stmt);
+ update_stmt (cond_stmt);
+ /* Header copying is a special case of jump threading, so use
+ common code to update loop body exit condition. */
+ update_bb_profile_for_threading (region[i], entry_count, e);
+ eliminated_edge = NULL;
+ }
+ else
+ region[i]->count -= region_copy[i]->count;
+ if (orig_eliminated_edges->contains (exit_e))
+ {
+ orig_eliminated_edges->remove (exit_e);
+ /* All exits will happen in exit_e_copy which is out of the
+ loop, so increase probability accordingly.
+ If the edge is eliminated_edge we already corrected
+ profile above. */
+ if (entry_count.nonzero_p () && eliminated_edge != exit_e)
+ set_edge_probability_and_rescale_others
+ (exit_e_copy, exit_e_count.probability_in
+ (entry_count));
+ /* Eliminate in-loop conditional. */
+ e->probability = profile_probability::always ();
+ exit_e->probability = profile_probability::never ();
+ gcond *cond_stmt = as_a <gcond *>(*gsi_last_bb (region[i]));
+ if (e->flags & EDGE_TRUE_VALUE)
+ gimple_cond_make_true (cond_stmt);
+ else
+ gimple_cond_make_false (cond_stmt);
+ update_stmt (cond_stmt);
+ }
+ entry_count = e_copy->count ();
}
+ /* Be sure that we seen all edges we are supposed to update. */
+ gcc_checking_assert (!eliminated_edge
+ && orig_eliminated_edges->is_empty ());
}
}
generated by cgit v1.1 at 2025-08-09 06:00:45 +0000