From d398949230786a4d678677fab0070ad779cc1c84 Mon Sep 17 00:00:00 2001 From: Richard Biener Date: Fri, 6 Nov 2020 15:13:56 +0100 Subject: make PRE constant value IDs negative This separates constant and non-constant value-ids to allow for a more efficient constant_value_id_p and for more efficient bit-packing inside the bitmap sets which never contain any constant values. There's further optimization opportunities but at this stage I'll do small refactorings. 2020-11-06 Richard Biener * tree-ssa-sccvn.h (get_max_constant_value_id): Declare. (get_next_constant_value_id): Likewise. (value_id_constant_p): Inline and simplify. * tree-ssa-sccvn.c (constant_value_ids): Remove. (next_constant_value_id): Add. (get_or_alloc_constant_value_id): Adjust. (value_id_constant_p): Remove definition. (get_max_constant_value_id): Define. (get_next_value_id): Add assert for overflow. (get_next_constant_value_id): Define. (run_rpo_vn): Adjust. (free_rpo_vn): Likewise. (do_rpo_vn): Initialize next_constant_value_id. * tree-ssa-pre.c (constant_value_expressions): New. (add_to_value): Split into constant/non-constant value handling. Avoid exact re-allocation. (vn_valnum_from_value_id): Adjust. (phi_translate_1): Remove spurious exact re-allocation. (bitmap_find_leader): Adjust. Make sure we return a CONSTANT value for a constant value id. (do_pre_regular_insertion): Use 2 auto-elements for avail. (do_pre_partial_partial_insertion): Likewise. (init_pre): Allocate constant_value_expressions. (fini_pre): Release constant_value_expressions. --- gcc/tree-ssa-pre.c | 57 +++++++++++++++++++++++++++++++++++------------------- 1 file changed, 37 insertions(+), 20 deletions(-) (limited to 'gcc/tree-ssa-pre.c') diff --git a/gcc/tree-ssa-pre.c b/gcc/tree-ssa-pre.c index 39c52c9..65e8aaa 100644 --- a/gcc/tree-ssa-pre.c +++ b/gcc/tree-ssa-pre.c @@ -444,6 +444,9 @@ public: /* Mapping from value id to expressions with that value_id. */ static vec value_expressions; +/* ??? We want to just record a single expression for each constant + value, one of kind CONSTANT. */ +static vec constant_value_expressions; /* Sets that we need to keep track of. */ typedef struct bb_bitmap_sets @@ -624,18 +627,30 @@ add_to_value (unsigned int v, pre_expr e) gcc_checking_assert (get_expr_value_id (e) == v); - if (v >= value_expressions.length ()) + if (value_id_constant_p (v)) { - value_expressions.safe_grow_cleared (v + 1, true); - } + if (-v >= constant_value_expressions.length ()) + constant_value_expressions.safe_grow_cleared (-v + 1); - set = value_expressions[v]; - if (!set) - { - set = BITMAP_ALLOC (&grand_bitmap_obstack); - value_expressions[v] = set; + set = constant_value_expressions[-v]; + if (!set) + { + set = BITMAP_ALLOC (&grand_bitmap_obstack); + constant_value_expressions[-v] = set; + } } + else + { + if (v >= value_expressions.length ()) + value_expressions.safe_grow_cleared (v + 1); + set = value_expressions[v]; + if (!set) + { + set = BITMAP_ALLOC (&grand_bitmap_obstack); + value_expressions[v] = set; + } + } bitmap_set_bit (set, get_or_alloc_expression_id (e)); } @@ -687,7 +702,11 @@ vn_valnum_from_value_id (unsigned int val) { bitmap_iterator bi; unsigned int i; - bitmap exprset = value_expressions[val]; + bitmap exprset; + if (value_id_constant_p (val)) + exprset = constant_value_expressions[-val]; + else + exprset = value_expressions[val]; EXECUTE_IF_SET_IN_BITMAP (exprset, 0, i, bi) { pre_expr vexpr = expression_for_id (i); @@ -1451,8 +1470,6 @@ phi_translate_1 (bitmap_set_t dest, else { new_val_id = get_next_value_id (); - value_expressions.safe_grow_cleared (get_max_value_id () + 1, - true); nary = vn_nary_op_insert_pieces (newnary->length, newnary->opcode, newnary->type, @@ -1603,11 +1620,7 @@ phi_translate_1 (bitmap_set_t dest, else { if (changed || !same_valid) - { - new_val_id = get_next_value_id (); - value_expressions.safe_grow_cleared - (get_max_value_id () + 1, true); - } + new_val_id = get_next_value_id (); else new_val_id = ref->value_id; if (!newoperands.exists ()) @@ -1745,7 +1758,7 @@ bitmap_find_leader (bitmap_set_t set, unsigned int val) { unsigned int i; bitmap_iterator bi; - bitmap exprset = value_expressions[val]; + bitmap exprset = constant_value_expressions[-val]; EXECUTE_IF_SET_IN_BITMAP (exprset, 0, i, bi) { @@ -1753,6 +1766,7 @@ bitmap_find_leader (bitmap_set_t set, unsigned int val) if (expr->kind == CONSTANT) return expr; } + gcc_unreachable (); } if (bitmap_set_contains_value (set, val)) { @@ -3190,7 +3204,7 @@ do_pre_regular_insertion (basic_block block, basic_block dom) bool new_stuff = false; vec exprs; pre_expr expr; - auto_vec avail; + auto_vec avail; int i; exprs = sorted_array_from_bitmap_set (ANTIC_IN (block)); @@ -3357,7 +3371,7 @@ do_pre_partial_partial_insertion (basic_block block, basic_block dom) bool new_stuff = false; vec exprs; pre_expr expr; - auto_vec avail; + auto_vec avail; int i; exprs = sorted_array_from_bitmap_set (PA_IN (block)); @@ -4111,7 +4125,9 @@ init_pre (void) expressions.create (0); expressions.safe_push (NULL); value_expressions.create (get_max_value_id () + 1); - value_expressions.safe_grow_cleared (get_max_value_id () + 1, true); + value_expressions.quick_grow_cleared (get_max_value_id () + 1); + constant_value_expressions.create (get_max_constant_value_id () + 1); + constant_value_expressions.quick_grow_cleared (get_max_constant_value_id () + 1); name_to_id.create (0); inserted_exprs = BITMAP_ALLOC (NULL); @@ -4142,6 +4158,7 @@ static void fini_pre () { value_expressions.release (); + constant_value_expressions.release (); expressions.release (); BITMAP_FREE (inserted_exprs); bitmap_obstack_release (&grand_bitmap_obstack); -- cgit v1.1