diff options
Diffstat (limited to 'gcc/gcse.c')
| -rw-r--r-- | gcc/gcse.c | 121 |
1 files changed, 59 insertions, 62 deletions
diff --git a/gcc/gcse.c b/gcc/gcse.c index 5535aa121a7..456a857259f 100644 --- a/gcc/gcse.c +++ b/gcc/gcse.c @@ -264,19 +264,8 @@ Software Foundation, 59 Temple Place - Suite 330, Boston, MA the result of the expression is copied to a new register, and the redundant expression is deleted by replacing it with this new register. Classic GCSE doesn't have this problem as much as it computes the reaching defs of - each register in each block and thus can try to use an existing register. - - ********************** - - A fair bit of simplicity is created by creating small functions for simple - tasks, even when the function is only called in one place. This may - measurably slow things down [or may not] by creating more function call - overhead than is necessary. The source is laid out so that it's trivial - to make the affected functions inline so that one can measure what speed - up, if any, can be achieved, and maybe later when things settle things can - be rearranged. - - Help stamp out big monolithic functions! */ + each register in each block and thus can try to use an existing + register. */ /* GCSE global vars. */ @@ -500,7 +489,10 @@ static bitmap modify_mem_list_set; /* This array parallels modify_mem_list, but is kept canonicalized. */ static rtx * canon_modify_mem_list; -static bitmap canon_modify_mem_list_set; + +/* Bitmap indexed by block numbers to record which blocks contain + function calls. */ +static bitmap blocks_with_calls; /* Various variables for statistics gathering. */ @@ -959,7 +951,7 @@ alloc_gcse_mem (rtx f) CUID_INSN (i++) = insn; /* Allocate vars to track sets of regs. */ - reg_set_bitmap = BITMAP_XMALLOC (); + reg_set_bitmap = BITMAP_ALLOC (NULL); /* Allocate vars to track sets of regs, memory per block. */ reg_set_in_block = sbitmap_vector_alloc (last_basic_block, max_gcse_regno); @@ -967,8 +959,8 @@ alloc_gcse_mem (rtx f) basic block. */ modify_mem_list = gcalloc (last_basic_block, sizeof (rtx)); canon_modify_mem_list = gcalloc (last_basic_block, sizeof (rtx)); - modify_mem_list_set = BITMAP_XMALLOC (); - canon_modify_mem_list_set = BITMAP_XMALLOC (); + modify_mem_list_set = BITMAP_ALLOC (NULL); + blocks_with_calls = BITMAP_ALLOC (NULL); } /* Free memory allocated by alloc_gcse_mem. */ @@ -979,12 +971,12 @@ free_gcse_mem (void) free (uid_cuid); free (cuid_insn); - BITMAP_XFREE (reg_set_bitmap); + BITMAP_FREE (reg_set_bitmap); sbitmap_vector_free (reg_set_in_block); free_modify_mem_tables (); - BITMAP_XFREE (modify_mem_list_set); - BITMAP_XFREE (canon_modify_mem_list_set); + BITMAP_FREE (modify_mem_list_set); + BITMAP_FREE (blocks_with_calls); } /* Compute the local properties of each recorded expression. @@ -1951,7 +1943,6 @@ canon_list_insert (rtx dest ATTRIBUTE_UNUSED, rtx unused1 ATTRIBUTE_UNUSED, alloc_EXPR_LIST (VOIDmode, dest_addr, canon_modify_mem_list[bb]); canon_modify_mem_list[bb] = alloc_EXPR_LIST (VOIDmode, dest, canon_modify_mem_list[bb]); - bitmap_set_bit (canon_modify_mem_list_set, bb); } /* Record memory modification information for INSN. We do not actually care @@ -1975,7 +1966,7 @@ record_last_mem_set_info (rtx insn) need to insert a pair of items, as canon_list_insert does. */ canon_modify_mem_list[bb] = alloc_INSN_LIST (insn, canon_modify_mem_list[bb]); - bitmap_set_bit (canon_modify_mem_list_set, bb); + bitmap_set_bit (blocks_with_calls, bb); } else note_stores (PATTERN (insn), canon_list_insert, (void*) insn); @@ -2199,17 +2190,13 @@ clear_modify_mem_tables (void) EXECUTE_IF_SET_IN_BITMAP (modify_mem_list_set, 0, i, bi) { free_INSN_LIST_list (modify_mem_list + i); - } - bitmap_clear (modify_mem_list_set); - - EXECUTE_IF_SET_IN_BITMAP (canon_modify_mem_list_set, 0, i, bi) - { free_insn_expr_list_list (canon_modify_mem_list + i); } - bitmap_clear (canon_modify_mem_list_set); + bitmap_clear (modify_mem_list_set); + bitmap_clear (blocks_with_calls); } -/* Release memory used by modify_mem_list_set and canon_modify_mem_list_set. */ +/* Release memory used by modify_mem_list_set. */ static void free_modify_mem_tables (void) @@ -2470,41 +2457,51 @@ compute_transp (rtx x, int indx, sbitmap *bmap, int set_p) return; case MEM: - FOR_EACH_BB (bb) - { - rtx list_entry = canon_modify_mem_list[bb->index]; + { + bitmap_iterator bi; + unsigned bb_index; - while (list_entry) - { - rtx dest, dest_addr; + /* First handle all the blocks with calls. We don't need to + do any list walking for them. */ + EXECUTE_IF_SET_IN_BITMAP (blocks_with_calls, 0, bb_index, bi) + { + if (set_p) + SET_BIT (bmap[bb_index], indx); + else + RESET_BIT (bmap[bb_index], indx); + } - if (CALL_P (XEXP (list_entry, 0))) - { - if (set_p) - SET_BIT (bmap[bb->index], indx); - else - RESET_BIT (bmap[bb->index], indx); - break; - } - /* LIST_ENTRY must be an INSN of some kind that sets memory. - Examine each hunk of memory that is modified. */ + /* Now iterate over the blocks which have memory modifications + but which do not have any calls. */ + EXECUTE_IF_AND_COMPL_IN_BITMAP (modify_mem_list_set, blocks_with_calls, + 0, bb_index, bi) + { + rtx list_entry = canon_modify_mem_list[bb_index]; - dest = XEXP (list_entry, 0); - list_entry = XEXP (list_entry, 1); - dest_addr = XEXP (list_entry, 0); + while (list_entry) + { + rtx dest, dest_addr; - if (canon_true_dependence (dest, GET_MODE (dest), dest_addr, - x, rtx_addr_varies_p)) - { - if (set_p) - SET_BIT (bmap[bb->index], indx); - else - RESET_BIT (bmap[bb->index], indx); - break; - } - list_entry = XEXP (list_entry, 1); - } - } + /* LIST_ENTRY must be an INSN of some kind that sets memory. + Examine each hunk of memory that is modified. */ + + dest = XEXP (list_entry, 0); + list_entry = XEXP (list_entry, 1); + dest_addr = XEXP (list_entry, 0); + + if (canon_true_dependence (dest, GET_MODE (dest), dest_addr, + x, rtx_addr_varies_p)) + { + if (set_p) + SET_BIT (bmap[bb_index], indx); + else + RESET_BIT (bmap[bb_index], indx); + break; + } + list_entry = XEXP (list_entry, 1); + } + } + } x = XEXP (x, 0); goto repeat; @@ -4133,7 +4130,7 @@ pre_edge_insert (struct edge_list *edge_list, struct expr **index_map) if (! occr->deleted_p) continue; - /* Insert this expression on this edge if if it would + /* Insert this expression on this edge if it would reach the deleted occurrence in BB. */ if (!TEST_BIT (inserted[e], j)) { @@ -5849,7 +5846,7 @@ find_loads (rtx x, rtx store_pattern, int after) /* Check if INSN kills the store pattern X (is aliased with it). AFTER is true if we are checking the case when store X occurs - after the insn. Return true if it it does. */ + after the insn. Return true if it does. */ static bool store_killed_in_insn (rtx x, rtx x_regs, rtx insn, int after) |