diff options
Diffstat (limited to 'gcc/tree-ssa-pre.c')
| -rw-r--r-- | gcc/tree-ssa-pre.c | 51 |
1 files changed, 30 insertions, 21 deletions
diff --git a/gcc/tree-ssa-pre.c b/gcc/tree-ssa-pre.c index 0ec3d3c7f7e..a6a68cf8372 100644 --- a/gcc/tree-ssa-pre.c +++ b/gcc/tree-ssa-pre.c @@ -540,8 +540,6 @@ static void bitmap_set_copy (bitmap_set_t, bitmap_set_t); static void bitmap_set_and (bitmap_set_t, bitmap_set_t); static bool bitmap_set_contains_value (bitmap_set_t, unsigned int); static void bitmap_insert_into_set (bitmap_set_t, pre_expr); -static void bitmap_insert_into_set_1 (bitmap_set_t, pre_expr, - unsigned int, bool); static bitmap_set_t bitmap_set_new (void); static tree create_expression_by_pieces (basic_block, pre_expr, gimple_seq *, tree); @@ -732,27 +730,22 @@ bitmap_remove_from_set (bitmap_set_t set, pre_expr expr) } } +/* Insert an expression EXPR into a bitmapped set. */ + static void -bitmap_insert_into_set_1 (bitmap_set_t set, pre_expr expr, - unsigned int val, bool allow_constants) +bitmap_insert_into_set (bitmap_set_t set, pre_expr expr) { - if (allow_constants || !value_id_constant_p (val)) + unsigned int val = get_expr_value_id (expr); + if (! value_id_constant_p (val)) { - /* We specifically expect this and only this function to be able to - insert constants into a set. */ + /* Note this is the only function causing multiple expressions + for the same value to appear in a set. This is needed for + TMP_GEN, PHI_GEN and NEW_SETs. */ bitmap_set_bit (&set->values, val); bitmap_set_bit (&set->expressions, get_or_alloc_expression_id (expr)); } } -/* Insert an expression EXPR into a bitmapped set. */ - -static void -bitmap_insert_into_set (bitmap_set_t set, pre_expr expr) -{ - bitmap_insert_into_set_1 (set, expr, get_expr_value_id (expr), false); -} - /* Copy a bitmapped set ORIG, into bitmapped set DEST. */ static void @@ -837,7 +830,7 @@ bitmap_set_and (bitmap_set_t dest, bitmap_set_t orig) } } -/* Subtract all values and expressions contained in ORIG from DEST. */ +/* Subtract all expressions contained in ORIG from DEST. */ static bitmap_set_t bitmap_set_subtract (bitmap_set_t dest, bitmap_set_t orig) @@ -859,7 +852,7 @@ bitmap_set_subtract (bitmap_set_t dest, bitmap_set_t orig) return result; } -/* Subtract all the values in bitmap set B from bitmap set A. */ +/* Subtract all values in bitmap set B from bitmap set A. */ static void bitmap_set_subtract_values (bitmap_set_t a, bitmap_set_t b) @@ -987,6 +980,11 @@ bitmap_value_insert_into_set (bitmap_set_t set, pre_expr expr) static void print_pre_expr (FILE *outfile, const pre_expr expr) { + if (! expr) + { + fprintf (outfile, "NULL"); + return; + } switch (expr->kind) { case CONSTANT: @@ -2115,7 +2113,8 @@ static sbitmap has_abnormal_preds; ANTIC_OUT[BLOCK] = phi_translate (ANTIC_IN[succ(BLOCK)]) ANTIC_IN[BLOCK] = clean(ANTIC_OUT[BLOCK] U EXP_GEN[BLOCK] - TMP_GEN[BLOCK]) -*/ + + Note that clean() is deferred until after the iteration. */ static bool compute_antic_aux (basic_block block, bool block_has_abnormal_pred_edge) @@ -2215,7 +2214,8 @@ compute_antic_aux (basic_block block, bool block_has_abnormal_pred_edge) bitmap_value_insert_into_set (ANTIC_IN (block), expression_for_id (bii)); - clean (ANTIC_IN (block)); + /* clean (ANTIC_IN (block)) is defered to after the iteration converged + because it can cause non-convergence, see for example PR81181. */ if (!was_visited || !bitmap_set_equal (old, ANTIC_IN (block))) changed = true; @@ -2418,7 +2418,9 @@ compute_antic (void) inverted_post_order_compute (&postorder); auto_sbitmap worklist (last_basic_block_for_fn (cfun) + 1); - bitmap_ones (worklist); + bitmap_clear (worklist); + FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR_FOR_FN (cfun)->preds) + bitmap_set_bit (worklist, e->src->index); while (changed) { if (dump_file && (dump_flags & TDF_DETAILS)) @@ -2449,6 +2451,12 @@ compute_antic (void) gcc_checking_assert (num_iterations < 500); } + /* We have to clean after the dataflow problem converged as cleaning + can cause non-convergence because it is based on expressions + rather than values. */ + FOR_EACH_BB_FN (block, cfun) + clean (ANTIC_IN (block)); + statistics_histogram_event (cfun, "compute_antic iterations", num_iterations); @@ -2456,7 +2464,8 @@ compute_antic (void) { /* For partial antic we ignore backedges and thus we do not need to perform any iteration when we process blocks in postorder. */ - int postorder_num = pre_and_rev_post_order_compute (NULL, postorder.address (), false); + int postorder_num + = pre_and_rev_post_order_compute (NULL, postorder.address (), false); for (i = postorder_num - 1 ; i >= 0; i--) { basic_block block = BASIC_BLOCK_FOR_FN (cfun, postorder[i]); |