You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING. If not, write to the Free
-Software Foundation, 59 Temple Place - Suite 330, Boston, MA
-02111-1307, USA. */
+Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
+02110-1301, USA. */
#include "config.h"
#include "system.h"
#include "hashtab.h"
#include "params.h"
#include "target.h"
+#include "timevar.h"
+#include "tree-pass.h"
/* The following code implements gcse after reload, the purpose of this
pass is to cleanup redundant loads generated by reload and other
/* Find the largest UID and create a mapping from UIDs to CUIDs. */
uid_cuid = xcalloc (get_max_uid () + 1, sizeof (int));
- i = 0;
+ i = 1;
FOR_EACH_BB (bb)
FOR_BB_INSNS (bb, insn)
{
fprintf (file, "expr: ");
print_rtl (file, expr->expr);
fprintf (file,"\nhashcode: %u\n", expr->hash);
- fprintf (file,"list of occurences:\n");
+ fprintf (file,"list of occurrences:\n");
occr = expr->avail_occr;
while (occr)
{
if (JUMP_P (insn) || set_noop_p (pat))
return;
- /* We shouldn't have any EH_REGION notes post reload. */
- gcc_assert (!find_reg_note (insn, REG_EH_REGION, NULL_RTX));
-
if (REG_P (dest))
{
if (/* Don't CSE something if we can't do a reg/reg copy. */
can_copy_p (GET_MODE (dest))
/* Is SET_SRC something we want to gcse? */
&& general_operand (src, GET_MODE (src))
+#ifdef STACK_REGS
+ /* Never consider insns touching the register stack. It may
+ create situations that reg-stack cannot handle (e.g. a stack
+ register live across an abnormal edge). */
+ && (REGNO (dest) < FIRST_STACK_REG || REGNO (dest) > LAST_STACK_REG)
+#endif
/* An expression is not available if its operands are
subsequently modified, including this insn. */
&& oprs_unchanged_p (src, insn, true))
can_copy_p (GET_MODE (src))
/* Is SET_DEST something we want to gcse? */
&& general_operand (dest, GET_MODE (dest))
+#ifdef STACK_REGS
+ /* As above for STACK_REGS. */
+ && (REGNO (src) < FIRST_STACK_REG || REGNO (src) > LAST_STACK_REG)
+#endif
&& ! (flag_float_store && FLOAT_MODE_P (GET_MODE (dest)))
/* Check if the memory expression is killed after insn. */
&& ! load_killed_in_block_p (INSN_CUID (insn) + 1, dest, true)
gcov_type ok_count = 0; /* Redundant load execution count. */
gcov_type critical_count = 0; /* Execution count of critical edges. */
edge_iterator ei;
+ bool critical_edge_split = false;
/* The execution count of the loads to be added to make the
load fully redundant. */
rtx next_pred_bb_end;
avail_insn = NULL_RTX;
+ avail_reg = NULL_RTX;
pred_bb = pred->src;
next_pred_bb_end = NEXT_INSN (BB_END (pred_bb));
for (a_occr = get_bb_avail_insn (pred_bb, expr->avail_occr); a_occr;
{
npred_ok++;
ok_count += pred->count;
+ if (! set_noop_p (PATTERN (gen_move_insn (copy_rtx (dest),
+ copy_rtx (avail_reg)))))
+ {
+ /* Check if there is going to be a split. */
+ if (EDGE_CRITICAL_P (pred))
+ critical_edge_split = true;
+ }
+ else /* Its a dead move no need to generate. */
+ continue;
occr = (struct unoccr *) obstack_alloc (&unoccr_obstack,
- sizeof (struct occr));
+ sizeof (struct unoccr));
occr->insn = avail_insn;
occr->pred = pred;
occr->next = avail_occrs;
}
else
{
+ /* Adding a load on a critical edge will cuase a split. */
+ if (EDGE_CRITICAL_P (pred))
+ critical_edge_split = true;
not_ok_count += pred->count;
unoccr = (struct unoccr *) obstack_alloc (&unoccr_obstack,
sizeof (struct unoccr));
if (/* No load can be replaced by copy. */
npred_ok == 0
/* Prevent exploding the code. */
- || (optimize_size && npred_ok > 1))
+ || (optimize_size && npred_ok > 1)
+ /* If we don't have profile information we cannot tell if splitting
+ a critical edge is profitable or not so don't do it. */
+ || ((! profile_info || ! flag_branch_probabilities
+ || targetm.cannot_modify_jumps_p ())
+ && critical_edge_split))
goto cleanup;
/* Check if it's worth applying the partial redundancy elimination. */
a_occr = get_bb_avail_insn (bb, a_occr->next));
if (!a_occr)
- delete_insn (insn);
+ {
+ stats.insns_deleted++;
+
+ if (dump_file)
+ {
+ fprintf (dump_file, "deleting insn:\n");
+ print_rtl_single (dump_file, insn);
+ fprintf (dump_file, "\n");
+ }
+ delete_insn (insn);
+ }
else
a_occr->deleted_p = 1;
gcse_after_reload_main (rtx f ATTRIBUTE_UNUSED)
{
- if (targetm.cannot_modify_jumps_p ())
- return;
-
memset (&stats, 0, sizeof (stats));
/* Allocate ememory for this pass.
free_mem ();
}
+\f
+static bool
+gate_handle_gcse2 (void)
+{
+ return (optimize > 0 && flag_gcse_after_reload);
+}
+
+
+static void
+rest_of_handle_gcse2 (void)
+{
+ gcse_after_reload_main (get_insns ());
+ rebuild_jump_labels (get_insns ());
+ delete_trivially_dead_insns (get_insns (), max_reg_num ());
+}
+
+struct tree_opt_pass pass_gcse2 =
+{
+ "gcse2", /* name */
+ gate_handle_gcse2, /* gate */
+ rest_of_handle_gcse2, /* execute */
+ NULL, /* sub */
+ NULL, /* next */
+ 0, /* static_pass_number */
+ TV_GCSE_AFTER_RELOAD, /* tv_id */
+ 0, /* properties_required */
+ 0, /* properties_provided */
+ 0, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ TODO_dump_func |
+ TODO_verify_flow | TODO_ggc_collect, /* todo_flags_finish */
+ 'J' /* letter */
+};
+
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