/* If-conversion support.
- Copyright (C) 2000, 2001, 2002, 2003 Free Software Foundation, Inc.
+ Copyright (C) 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
This file is part of GCC.
/* True if life data ok at present. */
static bool life_data_ok;
-/* The post-dominator relation on the original block numbers. */
-static dominance_info post_dominators;
-
/* Forward references. */
static int count_bb_insns (basic_block);
static rtx first_active_insn (basic_block);
edge e;
flow_loops_find (&loops, LOOP_TREE);
+ free_dominance_info (CDI_DOMINATORS);
if (loops.num > 1)
{
#endif
/* Conversion succeeded. */
- if (rtl_dump_file)
- fprintf (rtl_dump_file, "%d insn%s converted to conditional execution.\n",
+ if (dump_file)
+ fprintf (dump_file, "%d insn%s converted to conditional execution.\n",
n_insns, (n_insns == 1) ? " was" : "s were");
/* Merge the blocks! */
static rtx noce_get_alt_condition (struct noce_if_info *, rtx, rtx *);
static int noce_try_minmax (struct noce_if_info *);
static int noce_try_abs (struct noce_if_info *);
+static int noce_try_sign_mask (struct noce_if_info *);
/* Helper function for noce_try_store_flag*. */
return TRUE;
}
+/* Convert "if (m < 0) x = b; else x = 0;" to "x = (m >> C) & b;". */
+
+static int
+noce_try_sign_mask (struct noce_if_info *if_info)
+{
+ rtx cond, t, m, c, seq;
+ enum machine_mode mode;
+ enum rtx_code code;
+
+ if (no_new_pseudos)
+ return FALSE;
+
+ cond = if_info->cond;
+ code = GET_CODE (cond);
+ m = XEXP (cond, 0);
+ c = XEXP (cond, 1);
+
+ t = NULL_RTX;
+ if (if_info->a == const0_rtx)
+ {
+ if ((code == LT && c == const0_rtx)
+ || (code == LE && c == constm1_rtx))
+ t = if_info->b;
+ }
+ else if (if_info->b == const0_rtx)
+ {
+ if ((code == GE && c == const0_rtx)
+ || (code == GT && c == constm1_rtx))
+ t = if_info->a;
+ }
+
+ if (! t || side_effects_p (t))
+ return FALSE;
+
+ /* We currently don't handle different modes. */
+ mode = GET_MODE (t);
+ if (GET_MODE (m) != mode)
+ return FALSE;
+
+ /* This is only profitable if T is cheap. */
+ if (rtx_cost (t, SET) >= COSTS_N_INSNS (2))
+ return FALSE;
+
+ start_sequence ();
+ c = gen_int_mode (GET_MODE_BITSIZE (mode) - 1, mode);
+ m = expand_binop (mode, ashr_optab, m, c, NULL_RTX, 0, OPTAB_DIRECT);
+ t = m ? expand_binop (mode, and_optab, m, t, NULL_RTX, 0, OPTAB_DIRECT)
+ : NULL_RTX;
+
+ if (!t)
+ {
+ end_sequence ();
+ return FALSE;
+ }
+
+ noce_emit_move_insn (if_info->x, t);
+ seq = get_insns ();
+ unshare_ifcvt_sequence (if_info, seq);
+ end_sequence ();
+ emit_insn_before_setloc (seq, if_info->jump,
+ INSN_LOCATOR (if_info->insn_a));
+ return TRUE;
+}
+
+
/* Similar to get_condition, only the resulting condition must be
valid at JUMP, instead of at EARLIEST. */
}
/* Disallow the "if (...) x = a;" form (with an implicit "else x = x;")
- for most optimizations if writing to x may trap, i.e. its a memory
+ for most optimizations if writing to x may trap, i.e. it's a memory
other than a static var or a stack slot. */
if (! set_b
&& GET_CODE (orig_x) == MEM
if (HAVE_conditional_move
&& noce_try_cmove_arith (&if_info))
goto success;
+ if (noce_try_sign_mask (&if_info))
+ goto success;
}
return FALSE;
{
bb = fallthru;
fallthru = block_fallthru (bb);
- if (post_dominators)
- delete_from_dominance_info (post_dominators, bb);
merge_blocks (combo_bb, bb);
num_true_changes++;
}
if (combo_bb->global_live_at_end)
COPY_REG_SET (combo_bb->global_live_at_end,
then_bb->global_live_at_end);
- if (post_dominators)
- delete_from_dominance_info (post_dominators, then_bb);
merge_blocks (combo_bb, then_bb);
num_true_changes++;
}
get their addresses taken. */
if (else_bb)
{
- if (post_dominators)
- delete_from_dominance_info (post_dominators, else_bb);
merge_blocks (combo_bb, else_bb);
num_true_changes++;
}
COPY_REG_SET (combo_bb->global_live_at_end,
join_bb->global_live_at_end);
- if (post_dominators)
- delete_from_dominance_info (post_dominators, join_bb);
merge_blocks (combo_bb, join_bb);
num_true_changes++;
}
/* Remove the jump and cruft from the end of the COMBO block. */
if (join_bb != EXIT_BLOCK_PTR)
- tidy_fallthru_edge (combo_bb->succ, combo_bb, join_bb);
+ tidy_fallthru_edge (combo_bb->succ);
}
num_updated_if_blocks++;
&& find_cond_trap (test_bb, then_edge, else_edge))
goto success;
- if (post_dominators
+ if (dom_computed[CDI_POST_DOMINATORS] >= DOM_NO_FAST_QUERY
&& (! HAVE_conditional_execution || reload_completed))
{
if (find_if_case_1 (test_bb, then_edge, else_edge))
return NULL;
success:
- if (rtl_dump_file)
- fprintf (rtl_dump_file, "Conversion succeeded on pass %d.\n", pass);
+ if (dump_file)
+ fprintf (dump_file, "Conversion succeeded on pass %d.\n", pass);
return ce_info.test_bb;
}
num_possible_if_blocks++;
- if (rtl_dump_file)
+ if (dump_file)
{
- fprintf (rtl_dump_file, "\nIF-THEN%s block found, pass %d, start block %d [insn %d], then %d [%d]",
+ fprintf (dump_file,
+ "\nIF-THEN%s block found, pass %d, start block %d "
+ "[insn %d], then %d [%d]",
(else_bb) ? "-ELSE" : "",
ce_info->pass,
- test_bb->index, (BB_HEAD (test_bb)) ? (int)INSN_UID (BB_HEAD (test_bb)) : -1,
- then_bb->index, (BB_HEAD (then_bb)) ? (int)INSN_UID (BB_HEAD (then_bb)) : -1);
+ test_bb->index,
+ BB_HEAD (test_bb) ? (int)INSN_UID (BB_HEAD (test_bb)) : -1,
+ then_bb->index,
+ BB_HEAD (then_bb) ? (int)INSN_UID (BB_HEAD (then_bb)) : -1);
if (else_bb)
- fprintf (rtl_dump_file, ", else %d [%d]",
- else_bb->index, (BB_HEAD (else_bb)) ? (int)INSN_UID (BB_HEAD (else_bb)) : -1);
+ fprintf (dump_file, ", else %d [%d]",
+ else_bb->index,
+ BB_HEAD (else_bb) ? (int)INSN_UID (BB_HEAD (else_bb)) : -1);
- fprintf (rtl_dump_file, ", join %d [%d]",
- join_bb->index, (BB_HEAD (join_bb)) ? (int)INSN_UID (BB_HEAD (join_bb)) : -1);
+ fprintf (dump_file, ", join %d [%d]",
+ join_bb->index,
+ BB_HEAD (join_bb) ? (int)INSN_UID (BB_HEAD (join_bb)) : -1);
if (ce_info->num_multiple_test_blocks > 0)
- fprintf (rtl_dump_file, ", %d %s block%s last test %d [%d]",
+ fprintf (dump_file, ", %d %s block%s last test %d [%d]",
ce_info->num_multiple_test_blocks,
(ce_info->and_and_p) ? "&&" : "||",
(ce_info->num_multiple_test_blocks == 1) ? "" : "s",
? (int)INSN_UID (BB_HEAD (ce_info->last_test_bb))
: -1));
- fputc ('\n', rtl_dump_file);
+ fputc ('\n', dump_file);
}
/* Make sure IF, THEN, and ELSE, blocks are adjacent. Actually, we get the
else
return FALSE;
- if (rtl_dump_file)
+ if (dump_file)
{
- fprintf (rtl_dump_file, "\nTRAP-IF block found, start %d, trap %d\n",
+ fprintf (dump_file, "\nTRAP-IF block found, start %d, trap %d\n",
test_bb->index, trap_bb->index);
}
/* Delete the trap block if possible. */
remove_edge (trap_bb == then_bb ? then_edge : else_edge);
if (trap_bb->pred == NULL)
- {
- if (post_dominators)
- delete_from_dominance_info (post_dominators, trap_bb);
- delete_block (trap_bb);
- }
+ delete_basic_block (trap_bb);
/* If the non-trap block and the test are now adjacent, merge them.
Otherwise we must insert a direct branch. */
edge then_succ = then_bb->succ;
int then_bb_index;
+ /* If we are partitioning hot/cold basic blocks, we don't want to
+ mess up unconditional or indirect jumps that cross between hot
+ and cold sections. */
+
+ if (flag_reorder_blocks_and_partition
+ && ((BB_END (then_bb)
+ && find_reg_note (BB_END (then_bb), REG_CROSSING_JUMP, NULL_RTX))
+ || (BB_END (else_bb)
+ && find_reg_note (BB_END (else_bb), REG_CROSSING_JUMP,
+ NULL_RTX))))
+ return FALSE;
+
/* THEN has one successor. */
if (!then_succ || then_succ->succ_next != NULL)
return FALSE;
return FALSE;
num_possible_if_blocks++;
- if (rtl_dump_file)
- fprintf (rtl_dump_file,
+ if (dump_file)
+ fprintf (dump_file,
"\nIF-CASE-1 found, start %d, then %d\n",
test_bb->index, then_bb->index);
new_bb = redirect_edge_and_branch_force (FALLTHRU_EDGE (test_bb), else_bb);
then_bb_index = then_bb->index;
- if (post_dominators)
- delete_from_dominance_info (post_dominators, then_bb);
- delete_block (then_bb);
+ delete_basic_block (then_bb);
/* Make rest of code believe that the newly created block is the THEN_BB
block we removed. */
{
new_bb->index = then_bb_index;
BASIC_BLOCK (then_bb_index) = new_bb;
- if (post_dominators)
- add_to_dominance_info (post_dominators, new_bb);
}
/* We've possibly created jump to next insn, cleanup_cfg will solve that
later. */
edge else_succ = else_bb->succ;
rtx note;
+ /* If we are partitioning hot/cold basic blocks, we don't want to
+ mess up unconditional or indirect jumps that cross between hot
+ and cold sections. */
+
+ if (flag_reorder_blocks_and_partition
+ && ((BB_END (then_bb)
+ && find_reg_note (BB_END (then_bb), REG_CROSSING_JUMP, NULL_RTX))
+ || (BB_END (else_bb)
+ && find_reg_note (BB_END (else_bb), REG_CROSSING_JUMP,
+ NULL_RTX))))
+ return FALSE;
+
/* ELSE has one successor. */
if (!else_succ || else_succ->succ_next != NULL)
return FALSE;
if (note && INTVAL (XEXP (note, 0)) >= REG_BR_PROB_BASE / 2)
;
else if (else_succ->dest->index < 0
- || dominated_by_p (post_dominators, then_bb,
+ || dominated_by_p (CDI_POST_DOMINATORS, then_bb,
else_succ->dest))
;
else
return FALSE;
num_possible_if_blocks++;
- if (rtl_dump_file)
- fprintf (rtl_dump_file,
+ if (dump_file)
+ fprintf (dump_file,
"\nIF-CASE-2 found, start %d, else %d\n",
test_bb->index, else_bb->index);
then_bb->global_live_at_start,
else_bb->global_live_at_end, BITMAP_IOR);
- if (post_dominators)
- delete_from_dominance_info (post_dominators, else_bb);
- delete_block (else_bb);
+ delete_basic_block (else_bb);
num_true_changes++;
num_updated_if_blocks++;
dead_or_predicable (basic_block test_bb, basic_block merge_bb,
basic_block other_bb, basic_block new_dest, int reversep)
{
- rtx head, end, jump, earliest, old_dest, new_label = NULL_RTX;
+ rtx head, end, jump, earliest = NULL_RTX, old_dest, new_label = NULL_RTX;
jump = BB_END (test_bb);
num_true_changes = 0;
life_data_ok = (x_life_data_ok != 0);
- if (! (* targetm.cannot_modify_jumps_p) ())
+ if ((! targetm.cannot_modify_jumps_p ())
+ && (!flag_reorder_blocks_and_partition || !no_new_pseudos))
mark_loop_exit_edges ();
- /* Free up basic_block_for_insn so that we don't have to keep it
- up to date, either here or in merge_blocks. */
- free_basic_block_vars (1);
-
/* Compute postdominators if we think we'll use them. */
- post_dominators = NULL;
if (HAVE_conditional_execution || life_data_ok)
- {
- post_dominators = calculate_dominance_info (CDI_POST_DOMINATORS);
- }
+ calculate_dominance_info (CDI_POST_DOMINATORS);
+
if (life_data_ok)
clear_bb_flags ();
pass++;
#ifdef IFCVT_MULTIPLE_DUMPS
- if (rtl_dump_file && pass > 1)
- fprintf (rtl_dump_file, "\n\n========== Pass %d ==========\n", pass);
+ if (dump_file && pass > 1)
+ fprintf (dump_file, "\n\n========== Pass %d ==========\n", pass);
#endif
FOR_EACH_BB (bb)
}
#ifdef IFCVT_MULTIPLE_DUMPS
- if (rtl_dump_file && cond_exec_changed_p)
- print_rtl_with_bb (rtl_dump_file, get_insns ());
+ if (dump_file && cond_exec_changed_p)
+ print_rtl_with_bb (dump_file, get_insns ());
#endif
}
while (cond_exec_changed_p);
#ifdef IFCVT_MULTIPLE_DUMPS
- if (rtl_dump_file)
- fprintf (rtl_dump_file, "\n\n========== no more changes\n");
+ if (dump_file)
+ fprintf (dump_file, "\n\n========== no more changes\n");
#endif
- if (post_dominators)
- free_dominance_info (post_dominators);
+ free_dominance_info (CDI_POST_DOMINATORS);
- if (rtl_dump_file)
- fflush (rtl_dump_file);
+ if (dump_file)
+ fflush (dump_file);
clear_aux_for_blocks ();
}
/* Write the final stats. */
- if (rtl_dump_file && num_possible_if_blocks > 0)
+ if (dump_file && num_possible_if_blocks > 0)
{
- fprintf (rtl_dump_file,
+ fprintf (dump_file,
"\n%d possible IF blocks searched.\n",
num_possible_if_blocks);
- fprintf (rtl_dump_file,
+ fprintf (dump_file,
"%d IF blocks converted.\n",
num_updated_if_blocks);
- fprintf (rtl_dump_file,
+ fprintf (dump_file,
"%d true changes made.\n\n\n",
num_true_changes);
}
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