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Commit af21714c by Martin Jambor Committed by Jan Hubicka
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re PR ipa/65478 (crafty performance regression) 


	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.

From-SVN: r221763
parent a1bff765
Showing with 123 additions and 8 deletions
gcc/ChangeLog
2015-03-27 Martin Jambor <mjambor@suse.cz>
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.
2015-03-27 Jan Hubicka <hubicka@ucw.cz>
PR ipa/65588
......
gcc/doc/invoke.texi
......@@ -10834,6 +10834,15 @@ IPA-CP calculates its own score of cloning profitability heuristics
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
......
gcc/ipa-cp.c
......@@ -811,6 +811,41 @@ set_all_contains_variable (struct ipcp_param_lattices *plats)
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_node *node)
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 cgraph_node *node, int time_benefit,
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 cgraph_node *node, int time_benefit,
{
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_topo_info *topo)
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);
}
......
gcc/ipa-prop.h
......@@ -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
......
gcc/params.def
......@@ -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 "
......
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