diff options
Diffstat (limited to 'gcc/ifcvt.c')
| -rw-r--r-- | gcc/ifcvt.c | 165 |
1 files changed, 83 insertions, 82 deletions
diff --git a/gcc/ifcvt.c b/gcc/ifcvt.c index 28f510cda29..e5d88970be0 100644 --- a/gcc/ifcvt.c +++ b/gcc/ifcvt.c @@ -43,10 +43,10 @@ #include "target.h" #include "timevar.h" #include "tree-pass.h" +#include "df.h" #include "vec.h" #include "vecprim.h" - #ifndef HAVE_conditional_execution #define HAVE_conditional_execution 0 #endif @@ -70,6 +70,8 @@ #define MAX_CONDITIONAL_EXECUTE (BRANCH_COST + 1) #endif +#define IFCVT_MULTIPLE_DUMPS 1 + #define NULL_BLOCK ((basic_block) NULL) /* # of IF-THEN or IF-THEN-ELSE blocks we looked at */ @@ -79,15 +81,12 @@ static int num_possible_if_blocks; execution. */ static int num_updated_if_blocks; -/* # of changes made which require life information to be updated. */ +/* # of changes made. */ static int num_true_changes; /* Whether conditional execution changes were made. */ static int cond_exec_changed_p; -/* True if life data ok at present. */ -static bool life_data_ok; - /* Forward references. */ static int count_bb_insns (basic_block); static bool cheap_bb_rtx_cost_p (basic_block, int); @@ -2773,6 +2772,7 @@ merge_if_block (struct ce_if_block * ce_info) /* All block merging is done into the lower block numbers. */ combo_bb = test_bb; + df_set_bb_dirty (test_bb); /* Merge any basic blocks to handle && and || subtests. Each of the blocks are on the fallthru path from the predecessor block. */ @@ -2847,7 +2847,8 @@ merge_if_block (struct ce_if_block * ce_info) else if (EDGE_COUNT (join_bb->preds) < 2 && join_bb != EXIT_BLOCK_PTR) { - /* We can merge the JOIN. */ + /* We can merge the JOIN cleanly and update the dataflow try + again on this pass.*/ merge_blocks (combo_bb, join_bb); num_true_changes++; } @@ -2887,6 +2888,11 @@ find_if_header (basic_block test_bb, int pass) then_edge = EDGE_SUCC (test_bb, 0); else_edge = EDGE_SUCC (test_bb, 1); + if (df_get_bb_dirty (then_edge->dest)) + return NULL; + if (df_get_bb_dirty (else_edge->dest)) + return NULL; + /* Neither edge should be abnormal. */ if ((then_edge->flags & EDGE_COMPLEX) || (else_edge->flags & EDGE_COMPLEX)) @@ -2946,6 +2952,8 @@ find_if_header (basic_block test_bb, int pass) success: if (dump_file) fprintf (dump_file, "Conversion succeeded on pass %d.\n", pass); + /* Set this so we continue looking. */ + cond_exec_changed_p = TRUE; return ce_info.test_bb; } @@ -3118,7 +3126,7 @@ cond_exec_find_if_block (struct ce_if_block * ce_info) if (EDGE_COUNT (then_bb->succs) > 0 && (!single_succ_p (then_bb) || (single_succ_edge (then_bb)->flags & EDGE_COMPLEX) - || (flow2_completed && tablejump_p (BB_END (then_bb), NULL, NULL)))) + || (epilogue_completed && tablejump_p (BB_END (then_bb), NULL, NULL)))) return FALSE; /* If the THEN block has no successors, conditional execution can still @@ -3165,7 +3173,7 @@ cond_exec_find_if_block (struct ce_if_block * ce_info) && single_succ (then_bb) == single_succ (else_bb) && single_pred_p (else_bb) && ! (single_succ_edge (else_bb)->flags & EDGE_COMPLEX) - && ! (flow2_completed && tablejump_p (BB_END (else_bb), NULL, NULL))) + && ! (epilogue_completed && tablejump_p (BB_END (else_bb), NULL, NULL))) join_bb = single_succ (else_bb); /* Otherwise it is not an IF-THEN or IF-THEN-ELSE combination. */ @@ -3314,6 +3322,10 @@ find_cond_trap (basic_block test_bb, edge then_edge, edge else_edge) /* Delete the trap block if possible. */ remove_edge (trap_bb == then_bb ? then_edge : else_edge); + df_set_bb_dirty (test_bb); + df_set_bb_dirty (then_bb); + df_set_bb_dirty (else_bb); + if (EDGE_COUNT (trap_bb->preds) == 0) { delete_basic_block (trap_bb); @@ -3452,7 +3464,8 @@ static int find_if_case_1 (basic_block test_bb, edge then_edge, edge else_edge) { basic_block then_bb = then_edge->dest; - basic_block else_bb = else_edge->dest, new_bb; + basic_block else_bb = else_edge->dest; + basic_block new_bb; int then_bb_index; /* If we are partitioning hot/cold basic blocks, we don't want to @@ -3508,11 +3521,6 @@ find_if_case_1 (basic_block test_bb, edge then_edge, edge else_edge) /* Conversion went ok, including moving the insns and fixing up the jump. Adjust the CFG to match. */ - bitmap_ior (test_bb->il.rtl->global_live_at_end, - else_bb->il.rtl->global_live_at_start, - then_bb->il.rtl->global_live_at_end); - - /* We can avoid creating a new basic block if then_bb is immediately followed by else_bb, i.e. deleting then_bb allows test_bb to fall thru to else_bb. */ @@ -3526,7 +3534,10 @@ find_if_case_1 (basic_block test_bb, edge then_edge, edge else_edge) } else new_bb = redirect_edge_and_branch_force (FALLTHRU_EDGE (test_bb), - else_bb); + else_bb); + + df_set_bb_dirty (test_bb); + df_set_bb_dirty (else_bb); then_bb_index = then_bb->index; delete_basic_block (then_bb); @@ -3535,15 +3546,12 @@ find_if_case_1 (basic_block test_bb, edge then_edge, edge else_edge) block we removed. */ if (new_bb) { - new_bb->index = then_bb_index; - SET_BASIC_BLOCK (then_bb_index, new_bb); + df_bb_replace (then_bb_index, new_bb); /* Since the fallthru edge was redirected from test_bb to new_bb, we need to ensure that new_bb is in the same partition as test bb (you can not fall through across section boundaries). */ BB_COPY_PARTITION (new_bb, test_bb); } - /* We've possibly created jump to next insn, cleanup_cfg will solve that - later. */ num_true_changes++; num_updated_if_blocks++; @@ -3626,10 +3634,8 @@ find_if_case_2 (basic_block test_bb, edge then_edge, edge else_edge) /* Conversion went ok, including moving the insns and fixing up the jump. Adjust the CFG to match. */ - bitmap_ior (test_bb->il.rtl->global_live_at_end, - then_bb->il.rtl->global_live_at_start, - else_bb->il.rtl->global_live_at_end); - + df_set_bb_dirty (test_bb); + df_set_bb_dirty (then_bb); delete_basic_block (else_bb); num_true_changes++; @@ -3745,8 +3751,7 @@ dead_or_predicable (basic_block test_bb, basic_block merge_bb, that any registers modified are dead at the branch site. */ rtx insn, cond, prev; - regset merge_set, tmp, test_live, test_set; - struct propagate_block_info *pbi; + bitmap merge_set, test_live, test_set; unsigned i, fail = 0; bitmap_iterator bi; @@ -3786,10 +3791,9 @@ dead_or_predicable (basic_block test_bb, basic_block merge_bb, TEST_SET = set of registers set between EARLIEST and the end of the block. */ - tmp = ALLOC_REG_SET (®_obstack); - merge_set = ALLOC_REG_SET (®_obstack); - test_live = ALLOC_REG_SET (®_obstack); - test_set = ALLOC_REG_SET (®_obstack); + merge_set = BITMAP_ALLOC (®_obstack); + test_live = BITMAP_ALLOC (®_obstack); + test_set = BITMAP_ALLOC (®_obstack); /* ??? bb->local_set is only valid during calculate_global_regs_live, so we must recompute usage for MERGE_BB. Not so bad, I suppose, @@ -3798,11 +3802,21 @@ dead_or_predicable (basic_block test_bb, basic_block merge_bb, expander called from noce_emit_cmove), we must resize the array first. */ if (max_regno < max_reg_num ()) + max_regno = max_reg_num (); + + FOR_BB_INSNS (merge_bb, insn) { - max_regno = max_reg_num (); - allocate_reg_info (max_regno, FALSE, FALSE); + if (INSN_P (insn)) + { + unsigned int uid = INSN_UID (insn); + struct df_ref **def_rec; + for (def_rec = DF_INSN_UID_DEFS (uid); *def_rec; def_rec++) + { + struct df_ref *def = *def_rec; + bitmap_set_bit (merge_set, DF_REF_REGNO (def)); + } + } } - propagate_block (merge_bb, tmp, merge_set, merge_set, 0); /* For small register class machines, don't lengthen lifetimes of hard registers before reload. */ @@ -3816,39 +3830,40 @@ dead_or_predicable (basic_block test_bb, basic_block merge_bb, fail = 1; } } - + /* For TEST, we're interested in a range of insns, not a whole block. Moreover, we're interested in the insns live from OTHER_BB. */ - - COPY_REG_SET (test_live, other_bb->il.rtl->global_live_at_start); - pbi = init_propagate_block_info (test_bb, test_live, test_set, test_set, - 0); - + + /* The loop below takes the set of live registers + after JUMP, and calculates the live set before EARLIEST. */ + bitmap_copy (test_live, DF_LIVE_IN (other_bb)); + df_simulate_artificial_refs_at_end (test_bb, test_live); for (insn = jump; ; insn = prev) { - prev = propagate_one_insn (pbi, insn); + if (INSN_P (insn)) + { + df_simulate_find_defs (insn, test_set); + df_simulate_one_insn_backwards (test_bb, insn, test_live); + } + prev = PREV_INSN (insn); if (insn == earliest) break; } - free_propagate_block_info (pbi); - /* We can perform the transformation if MERGE_SET & (TEST_SET | TEST_LIVE) and - TEST_SET & merge_bb->il.rtl->global_live_at_start + TEST_SET & DF_LIVE_IN (merge_bb) are empty. */ if (bitmap_intersect_p (test_set, merge_set) || bitmap_intersect_p (test_live, merge_set) - || bitmap_intersect_p (test_set, - merge_bb->il.rtl->global_live_at_start)) + || bitmap_intersect_p (test_set, DF_LIVE_IN (merge_bb))) fail = 1; - FREE_REG_SET (tmp); - FREE_REG_SET (merge_set); - FREE_REG_SET (test_live); - FREE_REG_SET (test_set); + BITMAP_FREE (merge_set); + BITMAP_FREE (test_live); + BITMAP_FREE (test_set); if (fail) return FALSE; @@ -3938,7 +3953,7 @@ dead_or_predicable (basic_block test_bb, basic_block merge_bb, /* Main entry point for all if-conversion. */ static void -if_convert (int x_life_data_ok) +if_convert (bool recompute_dominance) { basic_block bb; int pass; @@ -3946,7 +3961,6 @@ if_convert (int x_life_data_ok) num_possible_if_blocks = 0; num_updated_if_blocks = 0; num_true_changes = 0; - life_data_ok = (x_life_data_ok != 0); /* Some transformations in this pass can create new pseudos, if the pass runs before reload. Make sure we can do so. */ @@ -3958,11 +3972,10 @@ if_convert (int x_life_data_ok) free_dominance_info (CDI_DOMINATORS); /* Compute postdominators if we think we'll use them. */ - if (HAVE_conditional_execution || life_data_ok) + if (HAVE_conditional_execution || recompute_dominance) calculate_dominance_info (CDI_POST_DOMINATORS); - if (life_data_ok) - clear_bb_flags (); + df_set_flags (DF_LR_RUN_DCE); /* Go through each of the basic blocks looking for things to convert. If we have conditional execution, we make multiple passes to allow us to handle @@ -3970,6 +3983,9 @@ if_convert (int x_life_data_ok) pass = 0; do { + df_analyze (); + /* Only need to do dce on the first pass. */ + df_clear_flags (DF_LR_RUN_DCE); cond_exec_changed_p = FALSE; pass++; @@ -3980,9 +3996,10 @@ if_convert (int x_life_data_ok) FOR_EACH_BB (bb) { - basic_block new_bb; - while ((new_bb = find_if_header (bb, pass))) - bb = new_bb; + basic_block new_bb; + while (!df_get_bb_dirty (bb) + && (new_bb = find_if_header (bb, pass)) != NULL) + bb = new_bb; } #ifdef IFCVT_MULTIPLE_DUMPS @@ -4004,19 +4021,9 @@ if_convert (int x_life_data_ok) clear_aux_for_blocks (); - /* Rebuild life info for basic blocks that require it. */ - if (num_true_changes && life_data_ok) - { - /* If we allocated new pseudos, we must resize the array for sched1. */ - if (max_regno < max_reg_num ()) - { - max_regno = max_reg_num (); - allocate_reg_info (max_regno, FALSE, FALSE); - } - update_life_info_in_dirty_blocks (UPDATE_LIFE_GLOBAL_RM_NOTES, - PROP_DEATH_NOTES | PROP_SCAN_DEAD_CODE - | PROP_KILL_DEAD_CODE); - } + /* If we allocated new pseudos, we must resize the array for sched1. */ + if (max_regno < max_reg_num ()) + max_regno = max_reg_num (); /* Write the final stats. */ if (dump_file && num_possible_if_blocks > 0) @@ -4052,14 +4059,10 @@ rest_of_handle_if_conversion (void) if (dump_file) dump_flow_info (dump_file, dump_flags); cleanup_cfg (CLEANUP_EXPENSIVE); - reg_scan (get_insns (), max_reg_num ()); - if_convert (0); + if_convert (false); } - timevar_push (TV_JUMP); - cleanup_cfg (CLEANUP_EXPENSIVE); - reg_scan (get_insns (), max_reg_num ()); - timevar_pop (TV_JUMP); + cleanup_cfg (0); return 0; } @@ -4076,6 +4079,7 @@ struct tree_opt_pass pass_rtl_ifcvt = 0, /* properties_provided */ 0, /* properties_destroyed */ 0, /* todo_flags_start */ + TODO_df_finish | TODO_dump_func, /* todo_flags_finish */ 'C' /* letter */ }; @@ -4093,7 +4097,7 @@ static unsigned int rest_of_handle_if_after_combine (void) { no_new_pseudos = 0; - if_convert (1); + if_convert (true); no_new_pseudos = 1; return 0; } @@ -4111,6 +4115,7 @@ struct tree_opt_pass pass_if_after_combine = 0, /* properties_provided */ 0, /* properties_destroyed */ 0, /* todo_flags_start */ + TODO_df_finish | TODO_dump_func | TODO_ggc_collect, /* todo_flags_finish */ 'C' /* letter */ @@ -4126,13 +4131,8 @@ gate_handle_if_after_reload (void) static unsigned int rest_of_handle_if_after_reload (void) { - /* Last attempt to optimize CFG, as scheduling, peepholing and insn - splitting possibly introduced more crossjumping opportunities. */ - cleanup_cfg (CLEANUP_EXPENSIVE - | CLEANUP_UPDATE_LIFE - | (flag_crossjumping ? CLEANUP_CROSSJUMP : 0)); if (flag_if_conversion2) - if_convert (1); + if_convert (true); return 0; } @@ -4150,6 +4150,7 @@ struct tree_opt_pass pass_if_after_reload = 0, /* properties_provided */ 0, /* properties_destroyed */ 0, /* todo_flags_start */ + TODO_df_finish | TODO_dump_func | TODO_ggc_collect, /* todo_flags_finish */ 'E' /* letter */ |