Hi,
this patch improve crafty performance by avoiding ipa-cp clonning of
Search function that specializes the first iteration of the recursion.
The patch is by Martin, I only tested it and cleaned up code in count_callers
and set_single_call_flag
Bootstrapped/regtested x86_64-linux, comitted.
PR ipa/65478
* params.def (PARAM_IPA_CP_RECURSION_PENALTY) : New.
(PARAM_IPA_CP_SINGLE_CALL_PENALTY): Likewise.
* ipa-prop.h (ipa_node_params): New flags node_within_scc and
node_calling_single_call.
* ipa-cp.c (count_callers): New function.
(set_single_call_flag): Likewise.
(initialize_node_lattices): Count callers and set single_flag_call if
necessary.
(incorporate_penalties): New function.
(good_cloning_opportunity_p): Use it, dump new flags.
(propagate_constants_topo): Set node_within_scc flag if appropriate.
* doc/invoke.texi (ipa-cp-recursion-penalty,
ipa-cp-single-call-pentalty): Document.
Index: params.def
===================================================================
--- params.def (revision 221757)
+++ params.def (working copy)
@@ -999,6 +999,18 @@ DEFPARAM (PARAM_IPA_CP_EVAL_THRESHOLD,
"beneficial to clone.",
500, 0, 0)
+DEFPARAM (PARAM_IPA_CP_RECURSION_PENALTY,
+ "ipa-cp-recursion-penalty",
+ "Percentage penalty the recursive functions will receive when they "
+ "are evaluated for cloning.",
+ 40, 0, 100)
+
+DEFPARAM (PARAM_IPA_CP_SINGLE_CALL_PENALTY,
+ "ipa-cp-single-call-penalty",
+ "Percentage penalty functions containg a single call to another "
+ "function will receive when they are evaluated for cloning.",
+ 15, 0, 100)
+
DEFPARAM (PARAM_IPA_MAX_AGG_ITEMS,
"ipa-max-agg-items",
"Maximum number of aggregate content items for a parameter in "
Index: ipa-prop.h
===================================================================
--- ipa-prop.h (revision 221757)
+++ ipa-prop.h (working copy)
@@ -330,6 +330,10 @@ struct ipa_node_params
/* Node has been completely replaced by clones and will be removed after
ipa-cp is finished. */
unsigned node_dead : 1;
+ /* Node is involved in a recursion, potentionally indirect. */
+ unsigned node_within_scc : 1;
+ /* Node is calling a private function called only once. */
+ unsigned node_calling_single_call : 1;
};
/* ipa_node_params access functions. Please use these to access fields that
Index: ipa-cp.c
===================================================================
--- ipa-cp.c (revision 221757)
+++ ipa-cp.c (working copy)
@@ -811,6 +811,41 @@ set_all_contains_variable (struct ipcp_p
return ret;
}
+/* Worker of call_for_symbol_thunks_and_aliases, increment the integer DATA
+ points to by the number of callers to NODE. */
+
+static bool
+count_callers (cgraph_node *node, void *data)
+{
+ int *caller_count = (int *) data;
+
+ for (cgraph_edge *cs = node->callers; cs; cs = cs->next_caller)
+ /* Local thunks can be handled transparently, but if the thunk can not
+ be optimized out, count it as a real use. */
+ if (!cs->caller->thunk.thunk_p || !cs->caller->local.local)
+ ++*caller_count;
+ return false;
+}
+
+/* Worker of call_for_symbol_thunks_and_aliases, it is supposed to be called on
+ the one caller of some other node. Set the caller's corresponding flag. */
+
+static bool
+set_single_call_flag (cgraph_node *node, void *)
+{
+ cgraph_edge *cs = node->callers;
+ /* Local thunks can be handled transparently, skip them. */
+ while (cs && cs->caller->thunk.thunk_p && cs->caller->local.local)
+ cs = cs->next_caller;
+ if (cs)
+ {
+ gcc_assert (!cs->next_caller);
+ IPA_NODE_REF (cs->caller)->node_calling_single_call = true;
+ return true;
+ }
+ return false;
+}
+
/* Initialize ipcp_lattices. */
static void
@@ -822,7 +857,17 @@ initialize_node_lattices (struct cgraph_
int i;
gcc_checking_assert (node->has_gimple_body_p ());
- if (!cgraph_local_p (node))
+ if (cgraph_local_p (node))
+ {
+ int caller_count = 0;
+ node->call_for_symbol_thunks_and_aliases (count_callers, &caller_count,
+ true);
+ gcc_checking_assert (caller_count > 0);
+ if (caller_count == 1)
+ node->call_for_symbol_thunks_and_aliases (set_single_call_flag,
+ NULL, true);
+ }
+ else
{
/* When cloning is allowed, we can assume that externally visible
functions are not called. We will compensate this by cloning
@@ -2105,6 +2150,24 @@ hint_time_bonus (inline_hints hints)
return result;
}
+/* If there is a reason to penalize the function described by INFO in the
+ cloning goodness evaluation, do so. */
+
+static inline int64_t
+incorporate_penalties (ipa_node_params *info, int64_t evaluation)
+{
+ if (info->node_within_scc)
+ evaluation = (evaluation
+ * (100 - PARAM_VALUE (PARAM_IPA_CP_RECURSION_PENALTY))) / 100;
+
+ if (info->node_calling_single_call)
+ evaluation = (evaluation
+ * (100 - PARAM_VALUE (PARAM_IPA_CP_SINGLE_CALL_PENALTY)))
+ / 100;
+
+ return evaluation;
+}
+
/* Return true if cloning NODE is a good idea, given the estimated TIME_BENEFIT
and SIZE_COST and with the sum of frequencies of incoming edges to the
potential new clone in FREQUENCIES. */
@@ -2120,18 +2183,22 @@ good_cloning_opportunity_p (struct cgrap
gcc_assert (size_cost > 0);
+ struct ipa_node_params *info = IPA_NODE_REF (node);
if (max_count)
{
int factor = (count_sum * 1000) / max_count;
int64_t evaluation = (((int64_t) time_benefit * factor)
/ size_cost);
+ evaluation = incorporate_penalties (info, evaluation);
if (dump_file && (dump_flags & TDF_DETAILS))
fprintf (dump_file, " good_cloning_opportunity_p (time: %i, "
"size: %i, count_sum: " HOST_WIDE_INT_PRINT_DEC
- ") -> evaluation: " "%"PRId64
+ "%s%s) -> evaluation: " "%"PRId64
", threshold: %i\n",
time_benefit, size_cost, (HOST_WIDE_INT) count_sum,
+ info->node_within_scc ? ", scc" : "",
+ info->node_calling_single_call ? ", single_call" : "",
evaluation, PARAM_VALUE (PARAM_IPA_CP_EVAL_THRESHOLD));
return evaluation >= PARAM_VALUE (PARAM_IPA_CP_EVAL_THRESHOLD);
@@ -2140,13 +2207,16 @@ good_cloning_opportunity_p (struct cgrap
{
int64_t evaluation = (((int64_t) time_benefit * freq_sum)
/ size_cost);
+ evaluation = incorporate_penalties (info, evaluation);
if (dump_file && (dump_flags & TDF_DETAILS))
fprintf (dump_file, " good_cloning_opportunity_p (time: %i, "
- "size: %i, freq_sum: %i) -> evaluation: "
+ "size: %i, freq_sum: %i%s%s) -> evaluation: "
"%"PRId64 ", threshold: %i\n",
- time_benefit, size_cost, freq_sum, evaluation,
- PARAM_VALUE (PARAM_IPA_CP_EVAL_THRESHOLD));
+ time_benefit, size_cost, freq_sum,
+ info->node_within_scc ? ", scc" : "",
+ info->node_calling_single_call ? ", single_call" : "",
+ evaluation, PARAM_VALUE (PARAM_IPA_CP_EVAL_THRESHOLD));
return evaluation >= PARAM_VALUE (PARAM_IPA_CP_EVAL_THRESHOLD);
}
@@ -2637,9 +2707,12 @@ propagate_constants_topo (struct ipa_top
struct cgraph_edge *cs;
for (cs = v->callees; cs; cs = cs->next_callee)
- if (ipa_edge_within_scc (cs)
- && propagate_constants_accross_call (cs))
- push_node_to_stack (topo, cs->callee->function_symbol ());
+ if (ipa_edge_within_scc (cs))
+ {
+ IPA_NODE_REF (v)->node_within_scc = true;
+ if (propagate_constants_accross_call (cs))
+ push_node_to_stack (topo, cs->callee->function_symbol ());
+ }
v = pop_node_from_stack (topo);
}
Index: doc/invoke.texi
===================================================================
--- doc/invoke.texi (revision 221757)
+++ doc/invoke.texi (working copy)
@@ -10834,6 +10834,15 @@ IPA-CP calculates its own score of cloni
and performs those cloning opportunities with scores that exceed
@option{ipa-cp-eval-threshold}.
+@item ipa-cp-recursion-penalty
+Percentage penalty the recursive functions will receive when they
+are evaluated for cloning.
+
+@item ipa-cp-single-call-penalty
+Percentage penalty functions containg a single call to another
+function will receive when they are evaluated for cloning.
+
+
@item ipa-max-agg-items
IPA-CP is also capable to propagate a number of scalar values passed
in an aggregate. @option{ipa-max-agg-items} controls the maximum
