+/* If NODE was cloned, how much would program grow? */
+static long
+ipcp_estimate_growth (struct cgraph_node *node)
+{
+ struct cgraph_edge *cs;
+ int redirectable_node_callers = 0;
+ int removable_args = 0;
+ bool need_original = node->needed;
+ struct ipa_node_params *info;
+ int i, count;
+ int growth;
+
+ for (cs = node->callers; cs != NULL; cs = cs->next_caller)
+ if (cs->caller == node || !ipcp_need_redirect_p (cs))
+ redirectable_node_callers++;
+ else
+ need_original = true;
+
+ /* If we will be able to fully replace orignal node, we never increase
+ program size. */
+ if (!need_original)
+ return 0;
+
+ info = IPA_NODE_REF (node);
+ count = ipa_get_param_count (info);
+ for (i = 0; i < count; i++)
+ {
+ struct ipcp_lattice *lat = ipcp_get_lattice (info, i);
+ tree parm_tree = ipa_get_param (info, i);
+
+ /* We can proactively remove obviously unused arguments. */
+ if (is_gimple_reg (parm_tree)
+ && !gimple_default_def (DECL_STRUCT_FUNCTION (node->decl),
+ parm_tree))
+ removable_args++;
+
+ if (lat->type == IPA_CONST_VALUE)
+ removable_args++;
+ }
+
+ /* We make just very simple estimate of savings for removal of operand from
+ call site. Precise cost is dificult to get, as our size metric counts
+ constants and moves as free. Generally we are looking for cases that
+ small function is called very many times. */
+ growth = node->local.inline_summary.self_insns
+ - removable_args * redirectable_node_callers;
+ if (growth < 0)
+ return 0;
+ return growth;
+}
+
+
+/* Estimate cost of cloning NODE. */
+static long
+ipcp_estimate_cloning_cost (struct cgraph_node *node)
+{
+ int freq_sum = 1;
+ gcov_type count_sum = 1;
+ struct cgraph_edge *e;
+ int cost;
+
+ cost = ipcp_estimate_growth (node) * 1000;
+ if (!cost)
+ {
+ if (dump_file)
+ fprintf (dump_file, "Versioning of %s will save code size\n",
+ cgraph_node_name (node));
+ return 0;
+ }
+
+ for (e = node->callers; e; e = e->next_caller)
+ if (!bitmap_bit_p (dead_nodes, e->caller->uid)
+ && !ipcp_need_redirect_p (e))
+ {
+ count_sum += e->count;
+ freq_sum += e->frequency + 1;
+ }
+
+ if (max_count)
+ cost /= count_sum * 1000 / max_count + 1;
+ else
+ cost /= freq_sum * 1000 / REG_BR_PROB_BASE + 1;
+ if (dump_file)
+ fprintf (dump_file, "Cost of versioning %s is %i, (size: %i, freq: %i)\n",
+ cgraph_node_name (node), cost, node->local.inline_summary.self_insns,
+ freq_sum);
+ return cost + 1;
+}
+
+/* Return number of live constant parameters. */
+static int
+ipcp_const_param_count (struct cgraph_node *node)
+{
+ int const_param = 0;
+ struct ipa_node_params *info = IPA_NODE_REF (node);
+ int count = ipa_get_param_count (info);
+ int i;
+
+ for (i = 0; i < count; i++)
+ {
+ struct ipcp_lattice *lat = ipcp_get_lattice (info, i);
+ tree parm_tree = ipa_get_param (info, i);
+ if (ipcp_lat_is_insertable (lat)
+ /* Do not count obviously unused arguments. */
+ && (!is_gimple_reg (parm_tree)
+ || gimple_default_def (DECL_STRUCT_FUNCTION (node->decl),
+ parm_tree)))
+ const_param++;
+ }
+ return const_param;
+}
+
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