diff options
Diffstat (limited to 'gcc/cse.c')
| -rw-r--r-- | gcc/cse.c | 168 |
1 files changed, 69 insertions, 99 deletions
diff --git a/gcc/cse.c b/gcc/cse.c index e166ce99bbe..58055ddae06 100644 --- a/gcc/cse.c +++ b/gcc/cse.c @@ -45,6 +45,8 @@ Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA #include "params.h" #include "rtlhooks-def.h" #include "tree-pass.h" +#include "df.h" +#include "dbgcnt.h" /* The basic idea of common subexpression elimination is to go through the code, keeping a record of expressions that would @@ -347,27 +349,6 @@ static unsigned int cse_reg_info_timestamp; static HARD_REG_SET hard_regs_in_table; -/* CUID of insn that starts the basic block currently being cse-processed. */ - -static int cse_basic_block_start; - -/* CUID of insn that ends the basic block currently being cse-processed. */ - -static int cse_basic_block_end; - -/* Vector mapping INSN_UIDs to cuids. - The cuids are like uids but increase monotonically always. - We use them to see whether a reg is used outside a given basic block. */ - -static int *uid_cuid; - -/* Highest UID in UID_CUID. */ -static int max_uid; - -/* Get the cuid of an insn. */ - -#define INSN_CUID(INSN) (uid_cuid[INSN_UID (INSN)]) - /* Nonzero if cse has altered conditional jump insns in such a way that jump optimization should be redone. */ @@ -538,10 +519,6 @@ static int constant_pool_entries_regcost; struct cse_basic_block_data { - /* Lowest CUID value of insns in block. */ - int low_cuid; - /* Highest CUID value of insns in block. */ - int high_cuid; /* Total number of SETs in block. */ int nsets; /* Size of current branch path, if any. */ @@ -554,6 +531,11 @@ struct cse_basic_block_data } *path; }; + +/* Pointers to the live in/live out bitmaps for the boundaries of the + current EBB. */ +static bitmap cse_ebb_live_in, cse_ebb_live_out; + /* A simple bitmap to track which basic blocks have been visited already as part of an already processed extended basic block. */ static sbitmap cse_visited_basic_blocks; @@ -602,7 +584,7 @@ static void record_jump_cond (enum rtx_code, enum machine_mode, rtx, rtx, static void cse_insn (rtx, rtx); static void cse_prescan_path (struct cse_basic_block_data *); static void invalidate_from_clobbers (rtx); -static rtx cse_process_notes (rtx, rtx); +static rtx cse_process_notes (rtx, rtx, bool *); static void cse_extended_basic_block (struct cse_basic_block_data *); static void count_reg_usage (rtx, int *, rtx, int); static int check_for_label_ref (rtx *, void *); @@ -957,11 +939,10 @@ make_regs_eqv (unsigned int new, unsigned int old) && ((new < FIRST_PSEUDO_REGISTER && FIXED_REGNO_P (new)) || (new >= FIRST_PSEUDO_REGISTER && (firstr < FIRST_PSEUDO_REGISTER - || ((uid_cuid[REGNO_LAST_UID (new)] > cse_basic_block_end - || (uid_cuid[REGNO_FIRST_UID (new)] - < cse_basic_block_start)) - && (uid_cuid[REGNO_LAST_UID (new)] - > uid_cuid[REGNO_LAST_UID (firstr)])))))) + || (bitmap_bit_p (cse_ebb_live_out, new) + && !bitmap_bit_p (cse_ebb_live_out, firstr)) + || (bitmap_bit_p (cse_ebb_live_in, new) + && !bitmap_bit_p (cse_ebb_live_in, firstr)))))) { reg_eqv_table[firstr].prev = new; reg_eqv_table[new].next = firstr; @@ -2648,14 +2629,15 @@ cse_rtx_varies_p (rtx x, int from_alias) static void validate_canon_reg (rtx *xloc, rtx insn) { - rtx new = canon_reg (*xloc, insn); + if (*xloc) + { + rtx new = canon_reg (*xloc, insn); - /* If replacing pseudo with hard reg or vice versa, ensure the - insn remains valid. Likewise if the insn has MATCH_DUPs. */ - if (insn != 0 && new != 0) - validate_change (insn, xloc, new, 1); - else - *xloc = new; + /* If replacing pseudo with hard reg or vice versa, ensure the + insn remains valid. Likewise if the insn has MATCH_DUPs. */ + gcc_assert (insn && new); + validate_change (insn, xloc, new, 1); + } } /* Canonicalize an expression: @@ -4151,12 +4133,12 @@ cse_insn (rtx insn, rtx libcall_insn) This does nothing when a register is clobbered because we have already invalidated the reg. */ if (MEM_P (XEXP (y, 0))) - canon_reg (XEXP (y, 0), NULL_RTX); + canon_reg (XEXP (y, 0), insn); } else if (GET_CODE (y) == USE && ! (REG_P (XEXP (y, 0)) && REGNO (XEXP (y, 0)) < FIRST_PSEUDO_REGISTER)) - canon_reg (y, NULL_RTX); + canon_reg (y, insn); else if (GET_CODE (y) == CALL) { /* The result of apply_change_group can be ignored; see @@ -4170,14 +4152,14 @@ cse_insn (rtx insn, rtx libcall_insn) else if (GET_CODE (x) == CLOBBER) { if (MEM_P (XEXP (x, 0))) - canon_reg (XEXP (x, 0), NULL_RTX); + canon_reg (XEXP (x, 0), insn); } /* Canonicalize a USE of a pseudo register or memory location. */ else if (GET_CODE (x) == USE && ! (REG_P (XEXP (x, 0)) && REGNO (XEXP (x, 0)) < FIRST_PSEUDO_REGISTER)) - canon_reg (XEXP (x, 0), NULL_RTX); + canon_reg (XEXP (x, 0), insn); else if (GET_CODE (x) == CALL) { /* The result of apply_change_group can be ignored; see canon_reg. */ @@ -4195,8 +4177,12 @@ cse_insn (rtx insn, rtx libcall_insn) && (! rtx_equal_p (XEXP (tem, 0), SET_SRC (sets[0].rtl)) || GET_CODE (SET_DEST (sets[0].rtl)) == STRICT_LOW_PART)) { - src_eqv = fold_rtx (canon_reg (XEXP (tem, 0), NULL_RTX), insn); + /* The result of apply_change_group can be ignored; see canon_reg. */ + canon_reg (XEXP (tem, 0), insn); + apply_change_group (); + src_eqv = fold_rtx (XEXP (tem, 0), insn); XEXP (tem, 0) = src_eqv; + df_notes_rescan (insn); } /* Canonicalize sources and addresses of destinations. @@ -4861,6 +4847,7 @@ cse_insn (rtx insn, rtx libcall_insn) XEXP (note, 0) = simplify_replace_rtx (XEXP (note, 0), sets[i].orig_src, copy_rtx (new)); + df_notes_rescan (libcall_insn); } /* The result of apply_change_group can be ignored; see @@ -4979,6 +4966,7 @@ cse_insn (rtx insn, rtx libcall_insn) /* Record the actual constant value in a REG_EQUAL note, making a new one if one does not already exist. */ set_unique_reg_note (insn, REG_EQUAL, src_const); + df_notes_rescan (insn); } } @@ -5056,11 +5044,6 @@ cse_insn (rtx insn, rtx libcall_insn) else if (dest == pc_rtx && GET_CODE (src) == LABEL_REF && !LABEL_REF_NONLOCAL_P (src)) { - /* Now emit a BARRIER after the unconditional jump. */ - if (NEXT_INSN (insn) == 0 - || !BARRIER_P (NEXT_INSN (insn))) - emit_barrier_after (insn); - /* We reemit the jump in as many cases as possible just in case the form of an unconditional jump is significantly different than a computed jump or conditional jump. @@ -5086,11 +5069,6 @@ cse_insn (rtx insn, rtx libcall_insn) delete_insn_and_edges (insn); insn = new; - - /* Now emit a BARRIER after the unconditional jump. */ - if (NEXT_INSN (insn) == 0 - || !BARRIER_P (NEXT_INSN (insn))) - emit_barrier_after (insn); } else INSN_CODE (insn) = -1; @@ -5716,7 +5694,7 @@ invalidate_from_clobbers (rtx x) Return the replacement for X. */ static rtx -cse_process_notes (rtx x, rtx object) +cse_process_notes_1 (rtx x, rtx object, bool *changed) { enum rtx_code code = GET_CODE (x); const char *fmt = GET_RTX_FORMAT (code); @@ -5737,22 +5715,22 @@ cse_process_notes (rtx x, rtx object) case MEM: validate_change (x, &XEXP (x, 0), - cse_process_notes (XEXP (x, 0), x), 0); + cse_process_notes (XEXP (x, 0), x, changed), 0); return x; case EXPR_LIST: case INSN_LIST: if (REG_NOTE_KIND (x) == REG_EQUAL) - XEXP (x, 0) = cse_process_notes (XEXP (x, 0), NULL_RTX); + XEXP (x, 0) = cse_process_notes (XEXP (x, 0), NULL_RTX, changed); if (XEXP (x, 1)) - XEXP (x, 1) = cse_process_notes (XEXP (x, 1), NULL_RTX); + XEXP (x, 1) = cse_process_notes (XEXP (x, 1), NULL_RTX, changed); return x; case SIGN_EXTEND: case ZERO_EXTEND: case SUBREG: { - rtx new = cse_process_notes (XEXP (x, 0), object); + rtx new = cse_process_notes (XEXP (x, 0), object, changed); /* We don't substitute VOIDmode constants into these rtx, since they would impede folding. */ if (GET_MODE (new) != VOIDmode) @@ -5788,10 +5766,20 @@ cse_process_notes (rtx x, rtx object) for (i = 0; i < GET_RTX_LENGTH (code); i++) if (fmt[i] == 'e') validate_change (object, &XEXP (x, i), - cse_process_notes (XEXP (x, i), object), 0); + cse_process_notes (XEXP (x, i), object, changed), 0); return x; } + +static rtx +cse_process_notes (rtx x, rtx object, bool *changed) +{ + rtx new = cse_process_notes_1 (x, object, changed); + if (new != x) + *changed = true; + return new; +} + /* Find a path in the CFG, starting with FIRST_BB to perform CSE on. @@ -5966,14 +5954,12 @@ have_eh_succ_edges (basic_block bb) /* Scan to the end of the path described by DATA. Return an estimate of - the total number of SETs, and the lowest and highest insn CUID, of all - insns in the path. */ + the total number of SETs of all insns in the path. */ static void cse_prescan_path (struct cse_basic_block_data *data) { int nsets = 0; - int low_cuid = -1, high_cuid = -1; /* FIXME low_cuid not computed correctly */ int path_size = data->path_size; int path_entry; @@ -5996,21 +5982,9 @@ cse_prescan_path (struct cse_basic_block_data *data) nsets += XVECLEN (PATTERN (insn), 0); else nsets += 1; - - /* Ignore insns made by CSE in a previous traversal of this - basic block. They cannot affect the boundaries of the - basic block. - FIXME: When we only visit each basic block at most once, - this can go away. */ - if (INSN_UID (insn) <= max_uid && INSN_CUID (insn) > high_cuid) - high_cuid = INSN_CUID (insn); - if (INSN_UID (insn) <= max_uid && INSN_CUID (insn) < low_cuid) - low_cuid = INSN_CUID (insn); } } - data->low_cuid = low_cuid; - data->high_cuid = high_cuid; data->nsets = nsets; } @@ -6027,6 +6001,8 @@ cse_extended_basic_block (struct cse_basic_block_data *ebb_data) qty_table = XNEWVEC (struct qty_table_elem, max_qty); new_basic_block (); + cse_ebb_live_in = DF_LIVE_IN (ebb_data->path[0].bb); + cse_ebb_live_out = DF_LIVE_OUT (ebb_data->path[path_size - 1].bb); for (path_entry = 0; path_entry < path_size; path_entry++) { basic_block bb; @@ -6058,8 +6034,13 @@ cse_extended_basic_block (struct cse_basic_block_data *ebb_data) /* Process notes first so we have all notes in canonical forms when looking for duplicate operations. */ if (REG_NOTES (insn)) - REG_NOTES (insn) = cse_process_notes (REG_NOTES (insn), - NULL_RTX); + { + bool changed = false; + REG_NOTES (insn) = cse_process_notes (REG_NOTES (insn), + NULL_RTX, &changed); + if (changed) + df_notes_rescan (insn); + } /* Track when we are inside in LIBCALL block. Inside such a block we do not want to record destinations. The last @@ -6191,6 +6172,7 @@ cse_extended_basic_block (struct cse_basic_block_data *ebb_data) free (qty_table); } + /* Perform cse on the instructions of a function. F is the first instruction. @@ -6207,6 +6189,11 @@ cse_main (rtx f ATTRIBUTE_UNUSED, int nregs) int *rc_order = XNEWVEC (int, last_basic_block); int i, n_blocks; + df_set_flags (DF_LR_RUN_DCE); + df_analyze (); + df_set_flags (DF_DEFER_INSN_RESCAN); + + reg_scan (get_insns (), max_reg_num ()); init_cse_reg_info (nregs); ebb_data.path = XNEWVEC (struct branch_path, @@ -6229,19 +6216,6 @@ cse_main (rtx f ATTRIBUTE_UNUSED, int nregs) cse_visited_basic_blocks = sbitmap_alloc (last_basic_block); sbitmap_zero (cse_visited_basic_blocks); - /* Compute the mapping from uids to cuids. - CUIDs are numbers assigned to insns, like uids, except that - that cuids increase monotonically through the code. */ - max_uid = get_max_uid (); - uid_cuid = XCNEWVEC (int, max_uid + 1); - i = 0; - FOR_EACH_BB (bb) - { - rtx insn; - FOR_BB_INSNS (bb, insn) - INSN_CUID (insn) = ++i; - } - /* Loop over basic blocks in reverse completion order (RPO), excluding the ENTRY and EXIT blocks. */ n_blocks = pre_and_rev_post_order_compute (NULL, rc_order, false); @@ -6271,8 +6245,6 @@ cse_main (rtx f ATTRIBUTE_UNUSED, int nregs) needed for this path. For this, we take the number of sets and multiply that by MAX_RECOG_OPERANDS. */ max_qty = ebb_data.nsets * MAX_RECOG_OPERANDS; - cse_basic_block_start = ebb_data.low_cuid; - cse_basic_block_end = ebb_data.high_cuid; /* Dump the path we're about to process. */ if (dump_file) @@ -6284,7 +6256,6 @@ cse_main (rtx f ATTRIBUTE_UNUSED, int nregs) /* Clean up. */ end_alias_analysis (); - free (uid_cuid); free (reg_eqv_table); free (ebb_data.path); sbitmap_free (cse_visited_basic_blocks); @@ -6605,7 +6576,7 @@ delete_trivially_dead_insns (rtx insns, int nreg) /* If this is a dead insn, delete it and show registers in it aren't being used. */ - if (! live_insn) + if (! live_insn && dbg_cnt (delete_trivial_dead)) { count_reg_usage (insn, counts, NULL_RTX, -1); delete_insn_and_edges (insn); @@ -7009,11 +6980,10 @@ static unsigned int rest_of_handle_cse (void) { int tem; + if (dump_file) dump_flow_info (dump_file, dump_flags); - reg_scan (get_insns (), max_reg_num ()); - tem = cse_main (get_insns (), max_reg_num ()); /* If we are not running more CSE passes, then we are no longer @@ -7024,7 +6994,7 @@ rest_of_handle_cse (void) rebuild_jump_labels (get_insns ()); if (tem || optimize > 1) - cleanup_cfg (CLEANUP_EXPENSIVE); + cleanup_cfg (0); return 0; } @@ -7042,6 +7012,7 @@ struct tree_opt_pass pass_cse = 0, /* properties_provided */ 0, /* properties_destroyed */ 0, /* todo_flags_start */ + TODO_df_finish | TODO_dump_func | TODO_ggc_collect | TODO_verify_flow, /* todo_flags_finish */ @@ -7078,11 +7049,9 @@ rest_of_handle_cse2 (void) { timevar_push (TV_JUMP); rebuild_jump_labels (get_insns ()); - delete_dead_jumptables (); - cleanup_cfg (CLEANUP_EXPENSIVE); + cleanup_cfg (0); timevar_pop (TV_JUMP); } - reg_scan (get_insns (), max_reg_num ()); cse_not_expected = 1; return 0; } @@ -7101,6 +7070,7 @@ struct tree_opt_pass pass_cse2 = 0, /* properties_provided */ 0, /* properties_destroyed */ 0, /* todo_flags_start */ + TODO_df_finish | TODO_dump_func | TODO_ggc_collect | TODO_verify_flow, /* todo_flags_finish */ |