https://gcc.gnu.org/g:2e2274102964364a1b5fcd0a70d92c5f6f3c5e08
commit 2e2274102964364a1b5fcd0a70d92c5f6f3c5e08
Author: Ondřej Machota <ondrejmach...@gmail.com>
Date: Tue May 13 06:28:48 2025 +0200
rtl-ssa-dce: create debug instruction
Diff:
---
gcc/dce.cc | 219 +++++++++++++++---------------------------------
gcc/emit-rtl.cc | 2 +-
gcc/rtl-ssa/changes.cc | 8 +-
gcc/rtl-ssa/functions.h | 2 +-
gcc/rtl.h | 1 +
5 files changed, 74 insertions(+), 158 deletions(-)
diff --git a/gcc/dce.cc b/gcc/dce.cc
index 5b8648be5859..305bb0e63db6 100644
--- a/gcc/dce.cc
+++ b/gcc/dce.cc
@@ -17,7 +17,6 @@ You should have received a copy of the GNU General Public
License
along with GCC; see the file COPYING3. If not see
<http://www.gnu.org/licenses/>. */
-#include "bitmap.h"
#include "sbitmap.h"
#include <iostream>
#include <ostream>
@@ -1381,7 +1380,10 @@ private:
void sweep ();
void debuggize_insn (insn_info *);
- void debugize_insns (const std::unordered_set<insn_info *> &);
+
+ void unmark_debugizable(insn_info &, sbitmap &);
+ sbitmap find_debugizable(const std::unordered_set<insn_info *> &);
+ void debugize_insns (const sbitmap);
offset_bitmap m_marked;
sbitmap mm_marked_phis;
@@ -1640,7 +1642,7 @@ rtl_ssa_dce::reset_dead_debug_insn (insn_info *insn)
if (dump_file)
fprintf (dump_file, "Resetting debug insn: %d\n", insn->uid ());
- // bitmap_clear_bit (mm_marked, insn->uid () + offset);
+ m_marked.clear_bit (insn->uid ());
insn_change change (insn);
change.new_uses = {};
INSN_VAR_LOCATION_LOC (insn->rtl ()) = gen_rtx_UNKNOWN_VAR_LOC ();
@@ -1899,14 +1901,14 @@ replace_dead_reg(rtx x, const_rtx old_rtx
ATTRIBUTE_UNUSED, void *data)
}
// visit every marked instruction in INSN dependency tree and unmark it
-static void
-unmark_debugizable(const insn_info& insn, auto_sbitmap &debugizable)
+void
+rtl_ssa_dce::unmark_debugizable(insn_info &insn, sbitmap &debugizable)
{
auto_vec<insn_info *> worklist;
bitmap_set_bit (debugizable, insn.uid ());
worklist.safe_push (&insn);
- while (!worklist.empty ()) {
+ while (!worklist.is_empty ()) {
insn_info *current = worklist.pop ();
int current_uid = current->uid ();
@@ -1916,7 +1918,7 @@ unmark_debugizable(const insn_info& insn, auto_sbitmap
&debugizable)
bitmap_clear_bit(debugizable, current_uid);
// add all marked dependencies to the worklist
- for (def_info *def : current.defs())
+ for (def_info *def : current->defs())
{
if (def->kind() != access_kind::SET)
continue;
@@ -1932,14 +1934,20 @@ unmark_debugizable(const insn_info& insn, auto_sbitmap
&debugizable)
}
}
-static auto_sbitmap
-find_debugizable(const std::unordered_set<insn_info *> &depends_on_dead_phi)
+sbitmap
+rtl_ssa_dce::find_debugizable(const std::unordered_set<insn_info *>
&depends_on_dead_phi)
{
// only real instructions
- auto_sbitmap debugizable(get_max_uid () + 1);
+ sbitmap debugizable = sbitmap_alloc (get_max_uid () + 1);
bitmap_clear(debugizable);
for (insn_info *insn : crtl->ssa->reverse_all_insns ()) {
+ if (insn->is_artificial ())
+ continue;
+
+ // TODO: mark debug instructions that do not depend on a
+ // dead phi
+
if (insn->is_artificial () ||
(m_marked.get_bit (insn->uid ()) && !insn->is_debug_insn()))
continue;
@@ -1966,7 +1974,7 @@ find_debugizable(const std::unordered_set<insn_info *>
&depends_on_dead_phi)
asm_noperands (PATTERN (rtl)) >= 0)
{
unmark_debugizable(*insn, debugizable);
- continue; // TODO: call unmark_debugizable
+ continue;
}
// some of the checks might be duplicate:
@@ -1974,7 +1982,7 @@ find_debugizable(const std::unordered_set<insn_info *>
&depends_on_dead_phi)
{
if (insn->num_defs() > 1)
unmark_debugizable(*insn, debugizable);
- continue; // TODO: call unmark_debugizable if num_defs>1
+ continue;
}
def_info *def = *defs.begin ();
@@ -1984,7 +1992,24 @@ find_debugizable(const std::unordered_set<insn_info *>
&depends_on_dead_phi)
set_info *set = static_cast<set_info *> (def);
// this is a problem a bit
// TODO: check instruction dependencies and their debugizability
- if (!set->has_nondebug_insn_uses ())
+
+ // if some dependent is a debugizable
+ bool has_debug_uses = false;
+ for (use_info *use : set->all_uses())
+ {
+ if (!use->is_in_any_insn ())
+ continue;
+
+ insn_info *use_insn = use->insn();
+ gcc_assert(use_insn->is_real());
+
+ if (bitmap_bit_p(debugizable, use_insn->uid ())) {
+ has_debug_uses = true;
+ break;
+ }
+ }
+ // if (!set->has_nondebug_insn_uses ())
+ if (!has_debug_uses)
continue;
bitmap_set_bit (debugizable, insn->uid ());
@@ -1993,8 +2018,8 @@ find_debugizable(const std::unordered_set<insn_info *>
&depends_on_dead_phi)
return debugizable;
}
-static void
-bruh(const auto_sbitmap& debugizable)
+void
+rtl_ssa_dce::debugize_insns (const sbitmap debugizable)
{
for (insn_info *insn : crtl->ssa->reverse_all_insns ())
{
@@ -2026,76 +2051,10 @@ bruh(const auto_sbitmap& debugizable)
change.new_uses = insn->uses();
change.move_range = insn_range_info(insn);
- rtx_insn *bind = emit_debug_insn_before (bind_var_loc, rtl);
-
- register_replacement replacement;
- for (use_info *u : set->all_uses ()) {
- // TODO: transform dependent insns
- replacement.regno = u->regno();
- replacement.expr = dval;
-
- simplify_replace_fn_rtx(INSN_VAR_LOCATION_LOC(rtl), NULL_RTX,
replace_dead_reg, &replacement);
- }
- }
-}
-
-void
-rtl_ssa_dce::debugize_insns (const std::unordered_set<insn_info *>
&depends_on_dead_phi)
-{
- for (insn_info *insn : crtl->ssa->reverse_all_insns ()) {
- if (insn->is_artificial () ||
- (m_marked.get_bit (insn->uid ()) && !insn->is_debug_insn()))
- continue;
-
- // TODO: reset dead debug instructions - those that are dependend on a
dead phi
- if (depends_on_dead_phi.count (insn) > 0) {
- if (insn->is_debug_insn ())
- reset_dead_debug_insn (insn);
- continue;
- }
-
- gcc_checking_assert(insn->is_real ());
-
- rtx_insn *rtl = insn->rtl ();
- def_array defs = insn->defs ();
- rtx rtx_set;
-
- // If insn has debug uses and will be deleted, signalize it
- if (!MAY_HAVE_DEBUG_BIND_INSNS ||
- (rtx_set = single_set (rtl)) == NULL_RTX ||
- side_effects_p (SET_SRC (rtx_set)) ||
- asm_noperands (PATTERN (rtl)) >= 0)
- continue;
-
- // some of the checks might be duplicate:
- if (insn->num_defs () != 1)
- continue;
-
- def_info *def = *defs.begin ();
- if (def->kind () != access_kind::SET)
- continue;
-
- set_info *set = static_cast<set_info *> (def);
- if (!set->has_nondebug_insn_uses ())
- continue;
-
- rtx dval = make_debug_expr_from_rtl (SET_DEST (rtx_set));
-
- /* Emit a debug bind insn before the insn in which
- reg dies. */
- rtx bind_var_loc =
- gen_rtx_VAR_LOCATION (GET_MODE (SET_DEST (rtx_set)),
- DEBUG_EXPR_TREE_DECL (dval),
- SET_SRC (rtx_set),
- VAR_INIT_STATUS_INITIALIZED);
-
- obstack_watermark watermark = crtl->ssa->new_change_attempt();
- insn_info *debug_insn = crtl->ssa->create_insn(watermark, DEBUG_INSN,
bind_var_loc);
- insn_change change(debug_insn);
- change.new_uses = insn->uses();
- change.move_range = insn_range_info(insn);
-
- rtx_insn *bind = emit_debug_insn_before (bind_var_loc, rtl);
+ if (!rtl_ssa::restrict_movement (change))
+ std::cerr << "change move range location does not exists\n";
+ crtl->ssa->change_insn(change);
+ // rtx_insn *bind = emit_debug_insn_before (bind_var_loc, rtl);
register_replacement replacement;
for (use_info *u : set->all_uses ()) {
@@ -2111,82 +2070,38 @@ rtl_ssa_dce::debugize_insns (const
std::unordered_set<insn_info *> &depends_on_d
// debugized, update a bitmap. If the instruction is dead, walk over
// its dependencies with worklist and reset the bitmap for visited
// instructions.
- // 2. Do the actual debugizing.
-
- rtx set;
- // debugize_insns should be called only if MAY_HAVE_DEBUG_BIND_INSNS
- if (MAY_HAVE_DEBUG_BIND_INSNS
- && (set = single_set (rtl)) != NULL_RTX
- && !(*defs.begin ())->has_nondebug_insn_uses()
- // && is_dead_reg (SET_DEST (set), counts)
- // Proc tam byla tato podminka?
- // - debug statementy se sypou za kazdou definici ve zdrojaku, tedy
- // proto se chci ptat na to, kdyz existuje debug pouziti, tak je to
- // zajimava promenna
- /* Used at least once in some DEBUG_INSN. */
- // && counts[REGNO (SET_DEST (set)) + nreg] > 0
- // Tohle je ten bind nebo cast debug instrukce?
- /* And set exactly once. */
- // && counts[REGNO (SET_DEST (set)) + nreg * 2] == 1
- && !side_effects_p (SET_SRC (set))
- && asm_noperands (PATTERN (rtl)) < 0)
- {
- // TODO: musime predratovat zavisle debug insn - vsechny uses na nove
- // vytvorenou debug insn
- /* Create DEBUG_EXPR (and DEBUG_EXPR_DECL). */
- rtx dval = make_debug_expr_from_rtl (SET_DEST (set));
-
- /* Emit a debug bind insn before the insn in which
- reg dies. */
- rtx bind_var_loc =
- gen_rtx_VAR_LOCATION (GET_MODE (SET_DEST (set)),
- DEBUG_EXPR_TREE_DECL (dval),
- SET_SRC (set),
- VAR_INIT_STATUS_INITIALIZED);
- // count_reg_usage (bind_var_loc, counts + nreg, NULL_RTX, 1);
-
- rtl_ssa::obstack_watermark watermark = crtl->ssa->new_change_attempt();
- insn_info *debug_insn = crtl->ssa->create_insn(watermark, DEBUG_INSN,
rtx bind_var_loc);
- insn_change change(debug_insn);
- change.move_range = insn_range_info(insn)
- // TODO: chains and defs
-
- def_info *d = *defs.begin ();
- if (d->kind() == access_kind::SET) {
- set_info *s = static_cast<set_info *>(d);
- for (use_info *u : s->all_uses()) {
- // TODO: transform dependent insns
- }
- }
+ // 2. Do the actual debugizing.
+
+ // rtx set;
+ // // debugize_insns should be called only if MAY_HAVE_DEBUG_BIND_INSNS
+ // if (MAY_HAVE_DEBUG_BIND_INSNS
+ // && (set = single_set (rtl)) != NULL_RTX
+ // && !(*defs.begin ())->has_nondebug_insn_uses()
+ // // && is_dead_reg (SET_DEST (set), counts)
+ // // Proc tam byla tato podminka?
+ // // - debug statementy se sypou za kazdou definici ve zdrojaku, tedy
+ // // proto se chci ptat na to, kdyz existuje debug pouziti, tak je to
+ // // zajimava promenna
+ // /* Used at least once in some DEBUG_INSN. */
+ // // && counts[REGNO (SET_DEST (set)) + nreg] > 0
+ // // Tohle je ten bind nebo cast debug instrukce?
+ // /* And set exactly once. */
+ // // && counts[REGNO (SET_DEST (set)) + nreg * 2] == 1
+ // && !side_effects_p (SET_SRC (set))
+ // && asm_noperands (PATTERN (rtl)) < 0)
+ // {
- rtx_insn *bind = emit_debug_insn_before (bind_var_loc, rtl);
-
- // if (replacements == NULL)
- // replacements = XCNEWVEC (rtx, nreg);
- // replacements[REGNO (SET_DEST (set))] = dval;
- }
+ // }
}
+ sbitmap_free (debugizable);
// TODO: check that all of the debug insn uses are live,
- // othervise reset the instruction
+ // otherwise reset the instruction
}
static void
test (insn_info *insn)
{
- rtx_insn *rtl = insn->rtl ();
- rtx set = single_set (rtl);
- if (set == NULL_RTX || side_effects_p (SET_SRC (set))
- || asm_noperands (PATTERN (rtl)) >= 0)
- return;
-
- rtx dval = make_debug_expr_from_rtl (SET_DEST (set));
- rtx bind_var_loc
- = gen_rtx_VAR_LOCATION (GET_MODE (SET_DEST (set)),
- DEBUG_EXPR_TREE_DECL (dval), SET_SRC (set),
- VAR_INIT_STATUS_INITIALIZED);
-
- obstack_watermark watermark = crtl->ssa->new_change_attempt();
// Radeji bych zde videl pridani dval do rtl ssa
// crtl->ssa->create_insn(watermark, DEBUG_INSN, rtx pat);
diff --git a/gcc/emit-rtl.cc b/gcc/emit-rtl.cc
index 3e2c4309dee6..3e1e9a633c24 100644
--- a/gcc/emit-rtl.cc
+++ b/gcc/emit-rtl.cc
@@ -4153,7 +4153,7 @@ make_insn_raw (rtx pattern)
/* Like `make_insn_raw' but make a DEBUG_INSN instead of an insn. */
-static rtx_insn *
+rtx_insn *
make_debug_insn_raw (rtx pattern)
{
rtx_debug_insn *insn;
diff --git a/gcc/rtl-ssa/changes.cc b/gcc/rtl-ssa/changes.cc
index 4657aec47cd8..62518c515c92 100644
--- a/gcc/rtl-ssa/changes.cc
+++ b/gcc/rtl-ssa/changes.cc
@@ -256,7 +256,7 @@ rtl_ssa::changes_are_worthwhile (array_slice<insn_change
*const> changes,
// SET has been deleted. Clean up all remaining uses. Such uses are
// either dead phis or now-redundant live-out uses.
void
-function_info::process_uses_of_deleted_def (set_info *set, auto_sbitmap&
visited_phis)
+function_info::process_uses_of_deleted_def (set_info *set, auto_sbitmap
&visited_phis)
{
if (!set->has_any_uses ())
return;
@@ -268,7 +268,7 @@ function_info::process_uses_of_deleted_def (set_info *set,
auto_sbitmap& visited
if (use->is_in_phi ())
{
// This call will not recurse.
- process_uses_of_deleted_def (use->phi ());
+ process_uses_of_deleted_def (use->phi (), visited_phis);
delete_phi (use->phi ());
}
else
@@ -861,8 +861,8 @@ function_info::change_insns (array_slice<insn_change *>
changes)
auto *set = dyn_cast<set_info *> (def);
if (set && set->has_any_uses ())
{
- auto_sbitmap phis(m_next_phi_uid);
- process_uses_of_deleted_def (set);
+ auto_sbitmap visited_phis(m_next_phi_uid);
+ process_uses_of_deleted_def (set, visited_phis);
}
remove_def (def);
}
diff --git a/gcc/rtl-ssa/functions.h b/gcc/rtl-ssa/functions.h
index 2e20f5e47d72..033154dfa586 100644
--- a/gcc/rtl-ssa/functions.h
+++ b/gcc/rtl-ssa/functions.h
@@ -306,7 +306,7 @@ private:
bb_info *create_bb_info (basic_block);
void append_bb (bb_info *);
- void process_uses_of_deleted_def (set_info *);
+ void process_uses_of_deleted_def (set_info *set, auto_sbitmap &);
insn_info *add_placeholder_after (insn_info *);
void possibly_queue_changes (insn_change &);
void finalize_new_accesses (insn_change &, insn_info *,
diff --git a/gcc/rtl.h b/gcc/rtl.h
index 3b676c468805..15045376e2bc 100644
--- a/gcc/rtl.h
+++ b/gcc/rtl.h
@@ -3375,6 +3375,7 @@ extern rtx_insn *emit_clobber (rtx);
extern rtx_insn *gen_use (rtx);
extern rtx_insn *emit_use (rtx);
extern rtx_insn *make_insn_raw (rtx);
+extern rtx_insn *make_debug_insn_raw (rtx);
extern void add_function_usage_to (rtx, rtx);
extern rtx_call_insn *last_call_insn (void);
extern rtx_insn *previous_insn (rtx_insn *);
