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/* Code locality based function cloning.
Copyright The GNU Toolchain Authors
This file is part of GCC.
GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 3, or (at your option) any later
version.
GCC is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING3. If not see
<http://www.gnu.org/licenses/>. */
/* This file implements cloning required to improve partitioning of the
callgraph for locality considerations.
Partitioning for improving code locality.
This pass aims to place frequently executed callchains closer together in
memory to improve performance through improved locality. If any frequent
callchains cannot be placed together because they are already placed
elsewhere, local function clones are created and all callers near to the
clones are redirected to use this copy.
Locality code placement is done in 2 parts.
1. IPA pass to be executed after ipa-inline and before ipa-pure-const.
Execute stage prepares the plan to place all nodes into partitions.
2. WPA Partition stage actually implements the plan.
Brief overview of the IPA pass:
1. Create and sort callchains. If PGO is available, use real profile
counts. Otherwise, use a set of heuristics to sort the callchains.
2. Create a partition plan for the callchains, processing them in the sorted
order.
1. If a function is unpartitioned, place it in the current partition.
2. If a function is already placed in a partition away from current
partition as part of another callchain:
Create a local clone in current partition, if cloning criteria is
satisfied.
3. Redirect any new caller to a local clone if one exists.
Another heuristics can be used in the absense of profile information. This
approach uses C++ template instantiation types to group functions together.
Entry functions are sorted in the beginning by most used template types, and
callees are sorted as part of partition_callchain (), again by template
types.
For bothe schemes, partition size is param controlled to fine tune per
program behavior. */
#include "config.h"
#define INCLUDE_ALGORITHM
#include "system.h"
#include "coretypes.h"
#include "target.h"
#include "function.h"
#include "tree.h"
#include "alloc-pool.h"
#include "tree-pass.h"
#include "cgraph.h"
#include "symbol-summary.h"
#include "tree-vrp.h"
#include "symtab-thunks.h"
#include "sreal.h"
#include "ipa-cp.h"
#include "ipa-prop.h"
#include "ipa-fnsummary.h"
#include "ipa-modref-tree.h"
#include "ipa-modref.h"
#include "symtab-clones.h"
#include "demangle.h"
#include "ipa-locality-cloning.h"
/* Locality partitions, assigns nodes to partitions. These are used later in
WPA partitioning. */
vec<locality_partition> locality_partitions;
using loc_map_hash = int_hash<int, 0, -1>;
/* Map from original node to its latest clone. Gets overwritten whenever a new
clone is created from the same node. */
static std::unique_ptr<hash_map<loc_map_hash, cgraph_node *>> node_to_clone;
/* Map from clone to its original node. */
static std::unique_ptr<hash_map<loc_map_hash, cgraph_node *>> clone_to_node;
/* Data structure to hold static heuristics and orders for cgraph_nodes. */
struct locality_order
{
cgraph_node *node;
sreal order;
locality_order (cgraph_node *node, sreal order) : node (node), order (order)
{}
};
/* Data structure to hold information about unique template instantiations. */
struct templ_info
{
hashval_t templ_hash;
int count;
int order;
};
/* Data structure to hold accumulated edge frequencies for unique callees.
Frequencies of aliased callees are accumulated with the ultimate target
alias represented by ultimate_callee.
ultimate_caller is the ultimate non-inlined caller of the unique callee.
Edge is the first edge encountered for the callee. */
struct locality_callee_info
{
cgraph_node *ultimate_caller;
cgraph_node *ultimate_callee;
cgraph_edge *edge;
sreal freq;
};
/* Data structure to hold precomputed callchain information. */
struct locality_info
{
cgraph_node *node;
/* Consolidated callees, including callees of inlined nodes. */
vec<locality_callee_info *> all_callees;
/* Accumulated caller->node edge frequencies for unique callers. */
hash_map<loc_map_hash, sreal> caller_freq;
/* Accumulated node->callee edge frequencies for unique callees. */
hash_map<loc_map_hash, locality_callee_info> callee_info;
/* Template instantiation info. */
hashval_t templ_hash;
locality_info ()
{
all_callees.create (1);
templ_hash = 0;
}
~locality_info ()
{
all_callees.release ();
}
};
/* Template instantiation hash_map. */
typedef hash_map<int_hash<hashval_t, 0>, templ_info> hash_freq_map_t;
static std::unique_ptr<hash_freq_map_t> templ_hash_map;
/* Pool allocation for locality_info. */
static object_allocator<locality_info> loc_infos ("IPA locality callchain");
static
std::unique_ptr<hash_map<loc_map_hash, locality_info *>> node_to_ch_info;
/* Return locality_info for NODE if present, otherwise return NULL. */
static inline locality_info *
get_locality_info (cgraph_node *node)
{
locality_info **ninfo = node_to_ch_info->get (node->get_uid ());
if (ninfo)
return *ninfo;
return NULL;
}
/* Forward declaration. */
static int compare_node_uids (cgraph_node *n1, cgraph_node *n2);
/* Helper function to qsort all_callees in locality_info by edge hotness. */
static int
callee_default_cmp (const void *pa, const void *pb)
{
const locality_callee_info *a = *(static_cast<const locality_callee_info
*const *> (pa));
const locality_callee_info *b = *(static_cast<const locality_callee_info
*const *> (pb));
if (a->freq < b->freq)
return 1;
else if (a->freq > b->freq)
return -1;
return compare_node_uids (a->ultimate_callee, b->ultimate_callee);
}
/* Sort all_callees of NODE by template hashes and edge hotness.
all_callees is already sorted by call frequency. If templ_hash of the
caller is same as a callee's templ_hash then that callee is ordered first.
Callees having same templ_hash are sorted by call frequency, callees with
different templ_hash are sorted by the template order.
if (Both PA and PB have templates && PA's template == PB'template) ||
(Both A and B don't have templates): sort by frequency
if (PA doesn't have template && PB has) || (Both have different templates &&
caller's template == PB's template): PB before PA
if (PA has template && PB doesn't) || (Both have different templates &&
caller's template == PA's template): PA before PB
if (Both have different templates && both are different than caller's
template: sort by template order. */
static int
callee_templ_cmp (const void *pa, const void *pb)
{
const locality_callee_info *a = *static_cast<const locality_callee_info
*const *> (pa);
const locality_callee_info *b = *static_cast<const locality_callee_info
*const *> (pb);
locality_info *caller_info = get_locality_info (a->ultimate_caller);
hashval_t caller_hash = 0;
if (caller_info)
caller_hash = caller_info->templ_hash;
locality_info *ainfo = get_locality_info (a->edge->callee);
locality_info *binfo = get_locality_info (b->edge->callee);
templ_info *atinfo = NULL, *btinfo = NULL;
hashval_t a_hash = 0, b_hash = 0;
if (ainfo)
{
a_hash = ainfo->templ_hash;
atinfo = templ_hash_map->get (a_hash);
}
if (binfo)
{
b_hash = binfo->templ_hash;
btinfo = templ_hash_map->get (b_hash);
}
if (a_hash == b_hash)
{
/* We get here if both have same template type or both have 0 as hash. */
return callee_default_cmp (pa, pb);
}
else if (a_hash && (!b_hash || a_hash == caller_hash))
return -1;
else if (b_hash && (!a_hash || b_hash == caller_hash))
return 1;
else
{
gcc_assert (atinfo && btinfo);
if (atinfo->order < btinfo->order)
return -1;
/* Order being same is already handled above. */
return 1;
}
return callee_default_cmp (pa, pb);
}
/* Sort all_callees in INFO by edge hotness. */
static void
sort_all_callees_default (locality_info *info)
{
hash_map<loc_map_hash, locality_callee_info>::iterator iter
= info->callee_info.begin ();
for (; iter != info->callee_info.end (); ++iter)
info->all_callees.safe_push (&((*iter).second));
info->all_callees.qsort (callee_default_cmp);
}
/* Populate locality_info for NODE from its direct callees and callees via
inlined nodes. N is used to iterate callees of NODE and callees of inlined
callees of NODE. */
static void
populate_callee_locality_info (cgraph_node *node, cgraph_node *n,
locality_info *info)
{
for (cgraph_edge *e = n->callees; e; e = e->next_callee)
{
cgraph_node *c = e->callee->ultimate_alias_target ();
if (c->inlined_to == node)
populate_callee_locality_info (node, c, info);
else
{
bool existed;
locality_callee_info &cinfo = info->callee_info.get_or_insert
(c->get_uid (), &existed);
if (!existed)
{
cinfo.ultimate_callee = c;
cinfo.ultimate_caller = node;
cinfo.edge = e;
cinfo.freq = e->sreal_frequency ();
}
else
cinfo.freq = cinfo.freq + e->sreal_frequency ();
}
}
}
/* Forward declaration. */
static int static_profile_cmp (const void *pa, const void *pb);
/* Helper function for qsort; sort nodes in the descending order derived of
template instantiation types by frequency count. */
static int
static_profile_templ_cmp (const void *pa, const void *pb)
{
const locality_order *a = *static_cast<const locality_order *const *> (pa);
const locality_order *b = *static_cast<const locality_order *const *> (pb);
locality_info *ainfo = get_locality_info (a->node);
templ_info *atinfo = templ_hash_map->get (ainfo->templ_hash);
locality_info *binfo = get_locality_info (b->node);
templ_info *btinfo = templ_hash_map->get (binfo->templ_hash);
if ((atinfo && !btinfo)
|| (atinfo && btinfo && atinfo->order < btinfo->order))
return -1;
else if ((btinfo && !atinfo)
|| (atinfo && btinfo && atinfo->order > btinfo->order))
return 1;
return static_profile_cmp (pa, pb);
}
/* Helper function for qsort; sort template instantiation types in descending
order of their frequency count. */
static int
sort_templ_hashes_cmp (const void *pa, const void *pb)
{
const std::pair<hashval_t, int> *a = static_cast<const std::pair<hashval_t,
int> *> (pa);
const std::pair<hashval_t, int> *b = static_cast<const std::pair<hashval_t,
int> *> (pb);
if (a->second < b->second)
return 1;
else if (a->second > b->second)
return -1;
else
{
long long int res = (long long int)a->first - (long long int)b->first;
/* Hashes from templ_hash_map cannot be equal. */
gcc_assert (res != 0);
return res > 0 ? 1 : -1;
}
}
/* Sort template instantiation types and record the sorted order. */
static void
order_templ_hashes ()
{
auto_vec<std::pair<hashval_t, int>> templ_hashes;
hash_freq_map_t::iterator iter = templ_hash_map->begin ();
for (; iter != templ_hash_map->end (); ++iter)
templ_hashes.safe_push (std::make_pair ((*iter).first,
(*iter).second.count));
templ_hashes.qsort (sort_templ_hashes_cmp);
for (unsigned i = 0; i < templ_hashes.length (); i++)
{
templ_info *tinfo = templ_hash_map->get (templ_hashes[i].first);
gcc_assert (tinfo);
tinfo->order = i;
}
}
/* Populate locality_info for NODE from its direct callers. */
static void
populate_caller_locality_info (cgraph_node *node, locality_info *info)
{
struct cgraph_edge *e;
for (e = node->callers; e; e = e->next_caller)
{
/* Make a local decision about all edges for EDGE->caller but not the
other nodes already in the partition. Their edges will be visited
later or may have been visited before and not fit the
cut-off criteria. */
if (auto cfreq = info->caller_freq.get (e->caller->get_uid ()))
(*cfreq) = (*cfreq) + e->sreal_frequency ();
else
info->caller_freq.put (e->caller->get_uid (), e->sreal_frequency ());
}
}
/* Return true if template component is found in the demangled function name in
DC. */
static bool
locality_dc_template_p (struct demangle_component *dc)
{
switch (dc->type)
{
case DEMANGLE_COMPONENT_QUAL_NAME:
return locality_dc_template_p (dc->u.s_binary.left);
case DEMANGLE_COMPONENT_TEMPLATE:
return true;
default:
return false;
}
return false;
}
/* Generate hash for the template type from NODE's name if NODE represents a
templated functions. If present, record in INFO. */
static void
populate_templ_info (cgraph_node *node, locality_info *info)
{
if (!info)
return;
void *alloc = NULL;
const char *asm_name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME
(node->decl));
const char *demangled_name = cplus_demangle_v3 (asm_name, 0);
struct demangle_component *dc =
cplus_demangle_v3_components (asm_name, DMGL_NO_OPTS, &alloc);
if (demangled_name && dc && locality_dc_template_p (dc))
{
const char *templ = strchr (demangled_name, '<');
hashval_t t_hash = htab_hash_string (templ);
info->templ_hash = t_hash;
bool existed;
templ_info &tinfo = templ_hash_map->get_or_insert (t_hash, &existed);
if (existed)
tinfo.count = tinfo.count + 1;
else
tinfo.count = 1;
}
free (alloc);
}
/* Initialize locality_info for node V. If CLONE_P is true, V is a locality
clone; populate callee information for locality clones because caller info
is needed for cloning decisions and clones are not cloned again. Populate
both caller and callee info for non-clone nodes. */
static inline void
create_locality_info (cgraph_node *v, bool templ_p = false,
bool clone_p = false)
{
locality_info **info = node_to_ch_info->get (v->get_uid ());
gcc_assert (!info);
locality_info *vinfo = loc_infos.allocate ();
vinfo->node = v;
node_to_ch_info->put (v->get_uid (), vinfo);
/* Locality clones are not cloned again. */
if (!clone_p)
populate_caller_locality_info (v, vinfo);
populate_callee_locality_info (v, v, vinfo);
sort_all_callees_default (vinfo);
if (templ_p)
populate_templ_info (v, vinfo);
}
/* Return true if NODE is already in some partition. */
static inline bool
node_partitioned_p (cgraph_node *node)
{
return node->aux;
}
/* Add symbol NODE to partition PART. */
static void
add_node_to_partition (locality_partition part, cgraph_node *node)
{
struct cgraph_edge *e;
if (node_partitioned_p (node))
return;
part->nodes.safe_push (node);
node->aux = (void *) (uintptr_t) (part->part_id);
if (!node->alias && node->get_partitioning_class () == SYMBOL_PARTITION)
part->insns += ipa_size_summaries->get (node)->size;
/* Add all inline clones and callees that are duplicated. */
for (e = node->callees; e; e = e->next_callee)
if (!e->inline_failed)
add_node_to_partition (part, e->callee);
/* omp declare_variant_alt or transparent_alias with definition or linker
discardable (non-local comdat but not forced and not
used by non-LTO). */
else if (e->callee->get_partitioning_class () == SYMBOL_DUPLICATE)
add_node_to_partition (part, e->callee);
/* Add all thunks associated with the function. */
for (e = node->callers; e; e = e->next_caller)
if (e->caller->thunk && !e->caller->inlined_to)
add_node_to_partition (part, e->caller);
/* Add all aliases associated with the symbol. */
struct ipa_ref *ref;
FOR_EACH_ALIAS (node, ref)
if (!ref->referring->transparent_alias)
{
cgraph_node *referring = dyn_cast<cgraph_node *> (ref->referring);
/* Only add function aliases.
Varpool refs are added later in LTO partitioning pass. */
if (referring)
add_node_to_partition (part, referring);
}
else
{
struct ipa_ref *ref2;
/* We do not need to add transparent aliases if they are not used.
However we must add aliases of transparent aliases if they exist. */
FOR_EACH_ALIAS (ref->referring, ref2)
{
/* Nested transparent aliases are not permitted. */
gcc_checking_assert (!ref2->referring->transparent_alias);
cgraph_node *referring = dyn_cast<cgraph_node *> (ref2->referring);
if (referring)
add_node_to_partition (part, referring);
}
}
}
/* Return TRUE if NODE is in PARTITION. */
static bool
node_in_partition_p (locality_partition partition, cgraph_node *node)
{
return ((uintptr_t) (partition->part_id) == (uintptr_t) (node->aux));
}
/* Helper function for qsort; to break ties. */
static int
compare_node_uids (cgraph_node *n1, cgraph_node *n2)
{
int res = n1->get_uid () - n2->get_uid ();
gcc_assert (res != 0);
return res > 0 ? 1 : -1;
}
/* Helper function for qsort; sort nodes by order. */
static int
static_profile_cmp (const void *pa, const void *pb)
{
const locality_order *a = *static_cast<const locality_order *const *> (pa);
const locality_order *b = *static_cast<const locality_order *const *> (pb);
/* Ascending order. */
if (b->order < a->order)
return 1;
if (b->order > a->order)
return -1;
return compare_node_uids (a->node, b->node);
}
/* Helper function for qsort; sort nodes by profile count. */
static int
compare_edge_profile_counts (const void *pa, const void *pb)
{
const locality_order *a = *static_cast<const locality_order *const *> (pa);
const locality_order *b = *static_cast<const locality_order *const *> (pb);
profile_count cnt1 = a->node->count.ipa ();
profile_count cnt2 = b->node->count.ipa ();
if (!cnt1.compatible_p (cnt2))
return static_profile_cmp (pa, pb);
if (cnt1 < cnt2)
return 1;
if (cnt1 > cnt2)
return -1;
return static_profile_cmp (pa, pb);
}
/* Create and return a new partition and increment NPARTITIONS. */
static locality_partition
create_partition (int &npartitions)
{
locality_partition part = XCNEW (struct locality_partition_def);
npartitions++;
part->part_id = npartitions;
part->nodes.create (1);
part->insns = 0;
locality_partitions.safe_push (part);
return part;
}
/* Structure for holding profile count information of callers of a node. */
struct profile_stats
{
/* Sum of non-recursive call counts. */
profile_count nonrec_count;
/* Sum of recursive call counts. */
profile_count rec_count;
/* If non-NULL, this node is the target of alias or thunk and calls from this
should be count in rec_count. */
cgraph_node *target;
};
/* Initialize fields of STATS. */
static inline void
init_profile_stats (profile_stats *stats, cgraph_node *target = NULL)
{
stats->nonrec_count = profile_count::zero ();
stats->rec_count = profile_count::zero ();
stats->target = target;
}
/* Helper function of to accumulate call counts. */
static bool
accumulate_profile_counts_after_cloning (cgraph_node *node, void *data)
{
struct profile_stats *stats = (struct profile_stats *) data;
for (cgraph_edge *e = node->callers; e; e = e->next_caller)
{
if (!e->count.initialized_p ())
continue;
if (e->caller == stats->target)
stats->rec_count += e->count.ipa ();
else
stats->nonrec_count += e->count.ipa ();
}
return false;
}
/* NEW_NODE is a previously created clone of ORIG_NODE already present in
current partition. EDGES contains newly redirected edges to NEW_NODE.
Adjust profile information for both nodes and the edge. */
static void
adjust_profile_info_for_non_self_rec_edges (auto_vec<cgraph_edge *> &edges,
cgraph_node *new_node,
cgraph_node *orig_node)
{
profile_count orig_node_count = orig_node->count.ipa ();
profile_count edge_count = profile_count::zero ();
profile_count final_new_count = profile_count::zero ();
profile_count final_orig_count = profile_count::zero ();
for (unsigned i = 0; i < edges.length (); ++i)
if (edges[i]->count.initialized_p ())
edge_count += edges[i]->count.ipa ();
final_orig_count = orig_node_count - edge_count;
/* NEW_NODE->count was adjusted for other callers when the clone was
first created. Just add the new edge count. */
final_new_count = new_node->count + edge_count;
final_new_count = orig_node_count.combine_with_ipa_count (final_new_count);
orig_node->count = final_orig_count;
new_node->count = final_new_count;
if (dump_file)
{
fprintf (dump_file, "Adjusting profile information for %s\n",
new_node->dump_asm_name ());
fprintf (dump_file, "\tOriginal node %s\n", orig_node->dump_asm_name ());
fprintf (dump_file, "\tOriginal count: ");
orig_node_count.dump (dump_file);
fprintf (dump_file, "\n\tAdjusted original count to: ");
final_orig_count.dump (dump_file);
fprintf (dump_file, "\n\tAdjusted clone count to: ");
final_new_count.dump (dump_file);
fprintf (dump_file, "\n");
}
/* Scale all callee edges according to adjusted counts. */
profile_count orig_node_count_copy = orig_node_count;
profile_count::adjust_for_ipa_scaling (&final_new_count,
&orig_node_count_copy);
for (cgraph_edge *cs = new_node->callees; cs; cs = cs->next_callee)
cs->count = cs->count.apply_scale (final_new_count, orig_node_count_copy);
for (cgraph_edge *cs = new_node->indirect_calls; cs; cs = cs->next_callee)
cs->count = cs->count.apply_scale (final_new_count, orig_node_count_copy);
profile_count::adjust_for_ipa_scaling (&final_orig_count, &orig_node_count);
for (cgraph_edge *cs = orig_node->callees; cs; cs = cs->next_callee)
cs->count = cs->count.apply_scale (final_orig_count, orig_node_count);
for (cgraph_edge *cs = orig_node->indirect_calls; cs; cs = cs->next_callee)
cs->count = cs->count.apply_scale (final_orig_count, orig_node_count);
}
/* Adjust profile counts of NEW_NODE and ORIG_NODE, where NEW_NODE is a clone
of OLD_NODE.
Assumes that all eligible edges from current partition so far are redirected
to NEW_NODE and recursive edges are adjusted. */
static void
adjust_profile_info (cgraph_node *new_node, cgraph_node *orig_node)
{
/* If all calls to NEW_NODE are non-recursive, subtract corresponding count
from ORIG_NODE and assign to NEW_NODE, any unexpected remainder stays with
ORIG_NODE.
Recursive calls if present, likely contribute to majority of count;
scale according to redirected callers' count. */
profile_count orig_node_count = orig_node->count.ipa ();
profile_stats new_stats, orig_stats;
init_profile_stats (&new_stats);
init_profile_stats (&orig_stats);
new_node->call_for_symbol_thunks_and_aliases
(accumulate_profile_counts_after_cloning, &new_stats, false);
orig_node->call_for_symbol_thunks_and_aliases
(accumulate_profile_counts_after_cloning, &orig_stats, false);
profile_count orig_nonrec_count = orig_stats.nonrec_count;
profile_count orig_rec_count = orig_stats.rec_count;
profile_count new_nonrec_count = new_stats.nonrec_count;
profile_count new_rec_count = new_stats.rec_count;
profile_count final_new_count = new_nonrec_count;
profile_count final_orig_count = profile_count::zero ();
/* All calls to NEW_NODE are non-recursive or recursive calls have
zero count. */
if (!new_rec_count.nonzero_p ())
final_orig_count = orig_node_count - new_nonrec_count;
else
{
/* If ORIG_NODE is externally visible, indirect calls or calls from
another part of the code may contribute to the count.
update_profiling_info () from ipa-cp.cc pretends to have an extra
caller to represent the extra counts. */
if (!orig_node->local)
{
profile_count pretend_count = (orig_node_count - new_nonrec_count -
orig_nonrec_count - orig_rec_count);
orig_nonrec_count += pretend_count;
}
/* Remaining rec_count is assigned in proportion to clone's non-recursive
count. */
profile_count rec_count = orig_node_count - new_nonrec_count
- orig_nonrec_count;
profile_count new_rec_scaled
= rec_count.apply_scale (new_nonrec_count,
new_nonrec_count + orig_nonrec_count);
final_new_count += new_rec_scaled;
final_orig_count = orig_node_count - final_new_count;
}
final_new_count = orig_node_count.combine_with_ipa_count (final_new_count);
new_node->count = final_new_count;
orig_node->count = final_orig_count;
if (dump_file)
{
fprintf (dump_file, "Adjusting profile information for %s\n",
new_node->dump_asm_name ());
fprintf (dump_file, "\tOriginal node %s\n", orig_node->dump_asm_name ());
fprintf (dump_file, "\tOriginal count: ");
orig_node_count.dump (dump_file);
fprintf (dump_file, "\n\tAdjusted original count to: ");
final_orig_count.dump (dump_file);
fprintf (dump_file, "\n\tAdjusted clone count to: ");
final_new_count.dump (dump_file);
fprintf (dump_file, "\n");
}
/* Scale all callee edges according to adjusted counts. */
profile_count orig_node_count_copy = orig_node_count;
profile_count::adjust_for_ipa_scaling (&final_new_count,
&orig_node_count_copy);
for (cgraph_edge *cs = new_node->callees; cs; cs = cs->next_callee)
cs->count = cs->count.apply_scale (final_new_count, orig_node_count_copy);
for (cgraph_edge *cs = new_node->indirect_calls; cs; cs = cs->next_callee)
cs->count = cs->count.apply_scale (final_new_count, orig_node_count_copy);
profile_count::adjust_for_ipa_scaling (&final_orig_count, &orig_node_count);
for (cgraph_edge *cs = orig_node->callees; cs; cs = cs->next_callee)
cs->count = cs->count.apply_scale (final_orig_count, orig_node_count);
for (cgraph_edge *cs = orig_node->indirect_calls; cs; cs = cs->next_callee)
cs->count = cs->count.apply_scale (final_orig_count, orig_node_count);
}
/* Return true if EDGE can be safely redirected to another callee. */
static inline bool
edge_redirectable_p (cgraph_edge *edge, lto_locality_cloning_model cm)
{
if (cm == LTO_LOCALITY_NON_INTERPOSABLE_CLONING)
{
/* Interposability may change on edge basis. */
enum availability avail;
avail = edge->callee->get_availability (edge->caller);
if (avail <= AVAIL_INTERPOSABLE)
return false;
}
return true;
}
/* Create a locality clone of CNODE and redirect all callers present in
PARTITION.
Create a clone dpending on whether CNODE itself is a clone or not. */
static cgraph_node *
create_locality_clone (cgraph_node *cnode,
locality_partition partition, int &cl_num,
lto_locality_cloning_model cm)
{
cgraph_node *cl_node = NULL;
vec<cgraph_edge *> redirect_callers = vNULL;
/* All callers of cnode in current partition are redirected. */
struct cgraph_edge *edge;
for (edge = cnode->callers; edge; edge = edge->next_caller)
{
struct cgraph_node *caller = edge->caller;
if (node_in_partition_p (partition, caller) && caller->definition
&& caller != cnode && edge_redirectable_p (edge, cm))
redirect_callers.safe_push (edge);
}
const char *suffix = "locality_clone";
tree old_decl = cnode->decl;
tree new_decl = copy_node (old_decl);
/* Generate a new name for the new version. */
const char *name = IDENTIFIER_POINTER (DECL_NAME (old_decl));
DECL_NAME (new_decl) = clone_function_name (name, suffix, cl_num);
SET_DECL_ASSEMBLER_NAME (new_decl,
clone_function_name (old_decl, suffix, cl_num));
cl_num++;
if (dump_file)
fprintf (dump_file, "\tNew name %s\n",
IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (new_decl)));
cl_node = cnode->create_clone (new_decl, cnode->count /*profile_count*/,
false /*update_original*/, redirect_callers,
false /*call_duplication_hook*/,
NULL /*new_inlined_to*/,
NULL /*param_adjustments*/, suffix);
set_new_clone_decl_and_node_flags (cl_node);
if (cnode->ipa_transforms_to_apply.exists ())
cl_node->ipa_transforms_to_apply
= cnode->ipa_transforms_to_apply.copy ();
if (dump_file)
{
fprintf (dump_file, "Cloned Node: %s %s\n", cnode->dump_asm_name (),
cl_node->dump_asm_name ());
for (edge = cl_node->callers; edge; edge = edge->next_caller)
fprintf (dump_file, "Redirected callers: %s\n",
edge->caller->dump_asm_name ());
for (edge = cl_node->callees; edge; edge = edge->next_callee)
fprintf (dump_file, "Callees of clone: %s %d\n",
edge->callee->dump_asm_name (), edge->frequency ());
}
return cl_node;
}
/* Redirect recursive edges of CLONE to correctly point to CLONE. As part of
cloning process, all callee edges of a node are just duplicated but not
redirected. Therefore, these edges still call to original of CLONE.
For non-inlined CLONEs, NEW_CALLEE == CLONE and ORIG_CALLEE is CLONE's
original node.
For inlined node, self recursion to CLONE's original same as non-inlined,
additionally, calls to CLONE->inlined_to are also recursive:
NEW_CALLEE == CLONE->inlined_into and
ORIG_CALLEE == original node of CLONE->inlined_into. */
static void
adjust_recursive_callees (cgraph_node *clone, cgraph_node *new_callee,
cgraph_node *orig_callee)
{
cgraph_node *alias = NULL;
for (cgraph_edge *e = clone->callees; e; e = e->next_callee)
{
if (!e->inline_failed)
continue;
/* Only self-cycle or local alias are handled. */
cgraph_node *callee = e->callee;
if (callee == orig_callee)
{
cgraph_node **cl = node_to_clone->get (orig_callee->get_uid ());
gcc_assert (cl && *cl == new_callee);
e->redirect_callee_duplicating_thunks (new_callee);
if (dump_file)
fprintf (dump_file, "recursive call from %s to %s orig %s\n",
e->caller->dump_asm_name (), e->callee->dump_asm_name (),
callee->dump_asm_name ());
}
else if (callee->alias
&& e->callee->ultimate_alias_target () == orig_callee)
{
if (!alias)
{
alias = dyn_cast<cgraph_node *> (
new_callee->noninterposable_alias ());
}
e->redirect_callee_duplicating_thunks (alias);
if (dump_file)
fprintf (dump_file, "recursive call from %s to %s orig %s\n",
e->caller->dump_asm_name (), e->callee->dump_asm_name (),
callee->dump_asm_name ());
}
}
new_callee->expand_all_artificial_thunks ();
if (alias)
alias->expand_all_artificial_thunks ();
}
/* Create clones for CALLER's inlined callees, ORIG_INLINED_TO is the original
node from clone_as_needed () such that new_inlined_to is a clone of it. */
static void
inline_clones (cgraph_node *caller, cgraph_node *orig_inlined_to)
{
struct cgraph_edge *edge;
for (edge = caller->callees; edge; edge = edge->next_callee)
{
struct cgraph_node *callee = edge->callee;
if (edge->inline_failed)
continue;
if (callee->inlined_to != orig_inlined_to)
continue;
struct cgraph_node *new_inlined_to, *cl;
if (caller->inlined_to)
new_inlined_to = caller->inlined_to;
else
new_inlined_to = caller;
cl = callee->create_clone (callee->decl,
edge->count /*profile_count*/,
true /*update_original*/,
vNULL /*redirect_callers*/,
false /*call_duplication_hook*/,
new_inlined_to /*new_inlined_to*/,
NULL /*param_adjustments*/,
"locality_clone" /*suffix*/);
edge->redirect_callee (cl);
node_to_clone->put (callee->get_uid (), cl);
clone_to_node->put (cl->get_uid (), callee);
if (callee->thunk)
{
thunk_info *info = thunk_info::get (callee);
*thunk_info::get_create (cl) = *info;
}
adjust_recursive_callees (cl, new_inlined_to, orig_inlined_to);
adjust_recursive_callees (cl, cl, callee);
if (dump_file)
{
fprintf (dump_file, "Inline cloned\n");
cl->dump (dump_file);
}
/* Recursively inline till end of this callchain. */
inline_clones (cl, orig_inlined_to);
}
}
/* Clone EDGE->CALLEE if it or a clone of it is not already in PARTITION.
Redirect all callers of EDGE->CALLEE that are in PARTITION, not just the
EDGE. If a clone is already present in PARTITION, redirect all edges from
EDGE->CALLER to EDGE->CALLEE. This is because we only visit one edge per
caller to callee and redirect for all others from there.
If cloning, also recursively clone inlined functions till the end of the
callchain because inlined clones have 1-1 exclusive copy and edge from
caller to inlined node.
There are 2 flows possible:
1. Only redirect
1.1. cnode is already in current partition - cnode mustn't be a
locality_clone -> nothing to do
1.2. A clone of cnode is in current partition - find out if it's the
correct clone for edge - must be a locality_clone but the exact same
kind as callee i.e. orig or cp/sra clone, if yes, redirect, else go to #2
1.3. Cnode/a clone of cnode is in current partition but caller is inlined
2. Clone and redirect
2.1. cnode is original node
2.2. cnode itself is a clone
Clone inlines
Flavors of edges:
1. Normal -> orig nodes, locality clones or cp/sra clones
2. Recursive -> direct recursion
3. Alias -> recursion via aliasing or as a result of IPA code duplication
4. Inline -> shouldn't be included in callchain. */
static cgraph_node *
clone_node_as_needed (cgraph_edge *edge, locality_partition partition,
int &cl_num, lto_locality_cloning_model cm)
{
/* suitable_for_locality_cloning_p () currently prohibits cloning aliases due
to potential versioning and materialization issues. Could be enabled in
the future. suitable_for_locality_cloning_p () also checks for
interposability for CNODE but not for edge redirection. */
struct cgraph_node *cnode = edge->callee;
struct cgraph_node *caller = edge->caller;
/* If clone of cnode is already in the partition
Get latest clone of cnode. If current partition has cloned cnode, that
clone should be returned. Otherwise, clone from previous partition is
returned
Original node and its clone shouldn't co-exist in current partition
This is required if callee is partitioned via another edge before caller
was, and we are now visiting caller->callee edge
1) a -> b ==> a -> bc1; b was cloned say via d -> bc1, a is orig
2) ac1 -> b ==> ac1 -> bc1; b was cloned and a was just cloned
3) a -> bc1 and bc2 present, mustn't happen, b was cloned and a was
redirected without being partitioned first.
Why will we do this again - multiple edges and something's wrong in
partition_callchain ()
4) ac1 -> bc1 ==> ac1 -> bc2; a was cloned and we already got (1) in some
other partition
5) ac1 -> bc1 but no clone present in this PARTITION. Create from b, not
from bc1?
6) a -> b; a -> bc0; create new clone, no clone present
7) ac0 -> b; ac0 -> bc0 same as (6)
8) a -> bc0 and no clone present, mustn't happen, same as (3)
Redirect when bc1 is present and:
a -> b or ac -> b or ac -> bc0 */
cgraph_node *orig_cnode = cnode;
cgraph_node **o_cnode = clone_to_node->get (cnode->get_uid ());
if (o_cnode)
orig_cnode = *o_cnode;
cgraph_node **cnode_cl = node_to_clone->get (orig_cnode->get_uid ());
if (cnode_cl && node_in_partition_p (partition, *cnode_cl))
{
if (node_in_partition_p (partition, caller))
{
bool clone_p = false;
auto_vec<cgraph_edge *> redirected_edges;
for (cgraph_edge *ec = caller->callees; ec; ec = ec->next_callee)
if (ec->callee == cnode && edge_redirectable_p (ec, cm))
{
ec->redirect_callee_duplicating_thunks (*cnode_cl);
clone_p = true;
redirected_edges.safe_push (ec);
if (dump_file)
{
fprintf (dump_file, "clone present %s %s redirecting %s\n",
cnode->dump_asm_name (),
(*cnode_cl)->dump_asm_name (),
caller->dump_asm_name ());
}
}
if (clone_p)
{
(*cnode_cl)->expand_all_artificial_thunks ();
adjust_profile_info_for_non_self_rec_edges (redirected_edges,
*cnode_cl, cnode);
return NULL;
}
}
}
/* Create a new clone for a -> b, ac -> b.
For ac -> bc, should be done on bc or b?
bc could be from b_cp/b_sra or b. */
if (orig_cnode != cnode)
{
if (dump_file)
fprintf (dump_file, "Clone of clone %s %s\n", cnode->dump_asm_name (),
orig_cnode->dump_asm_name ());
return NULL;
}
struct cgraph_node *cloned_node
= create_locality_clone (cnode, partition, cl_num, cm);
gcc_assert (cloned_node);
if (!cloned_node)
return NULL;
node_to_clone->put (cnode->get_uid (), cloned_node);
clone_to_node->put (cloned_node->get_uid (), cnode);
adjust_recursive_callees (cloned_node, cloned_node, cnode);
symtab->call_cgraph_duplication_hooks (cnode, cloned_node);
adjust_profile_info (cloned_node, cnode);
/* Inline clones are created iff their inlined_to == CNODE. */
inline_clones (cloned_node, cnode);
return cloned_node;
}
/* Determine if EDGE->CALLEE is suitable for cloning. It is assummed that the
callee is not an inlined node. */
static bool
suitable_for_locality_cloning_p (cgraph_edge *edge,
lto_locality_cloning_model cm)
{
cgraph_node *node = edge->callee;
if (!node->versionable)
return false;
/* Out-of-line locality clones of ipcp or sra clones will be created in this
pass after IPA inline is run. A locality clone has the same function
body and the same updated signature as the ipcp/sra clone.
This fails or asserts based on how the clone is created:
1. If param_adjustments and tree_map are not recorded for locality clone:
clone materialization (tree_function_versioning ()) fails when
updating signature and remapping calls because clone_of (ipcp/sra
clone) and locality clone differ in param information.
2. If param_adjustments and tree_map are provided: asserts are triggered
in fnsummary duplication because IPA inline resets some summaries.
One inelegant solution is to provide param_adjustments and tree_map, and
then set clone_of to ipcp/sra clone's clone_of. However, this sometimes
results in segmentation fault when the compiled program is run.
Disabling clone of clones altogether for now with an aim to resolve this
is future. */
if (node->clone_of)
return false;
if (node->alias)
return false;
if (edge->recursive_p ())
return false;
if (!node->definition)
return false;
/* Don't clone NODE if IPA count of NODE or EDGE is zero. */
if (!node->count.ipa ().nonzero_p () || !edge->count.ipa ().nonzero_p ())
return false;
if (cm == LTO_LOCALITY_NON_INTERPOSABLE_CLONING)
{
/* Interposability may change on edge basis. */
enum availability avail;
edge->callee->ultimate_alias_target (&avail, edge->caller);
if (avail <= AVAIL_INTERPOSABLE)
return false;
}
return true;
}
/* Return true if edge->callee->ultimate_alias_target can be cloned. */
static bool
clone_node_p (cgraph_edge *edge, lto_locality_cloning_model cloning_model,
double freq_cutoff, int size)
{
cgraph_node *node = edge->callee->ultimate_alias_target ();
if (!suitable_for_locality_cloning_p (edge, cloning_model))
return false;
if (!node->alias)
if (ipa_size_summaries->get (node)->size >= size)
return false;
if (freq_cutoff != 0.0)
{
locality_info *info = get_locality_info (node);
gcc_assert (info);
if (auto cfreq = info->caller_freq.get (edge->caller->get_uid ()))
{
if ((*cfreq).to_double () < freq_cutoff)
return false;
}
else if (edge->sreal_frequency ().to_double () < freq_cutoff)
return false;
}
return true;
}
/* Partition NODE's callees into PARTITION or clone if already partitioned and
satisfies cloning criteria such as CLONING_MODEL, REAL_FREQ and SIZE
cut-offs. */
/* callgraph can have multiple caller to callee edges for multiple callsites
For the first such edge, we make decisions about cutoffs and cloning because
we redirect ALL callsites to cloned callee, not just one of them. */
static void
partition_callchain (cgraph_node *node, locality_partition &partition,
lto_locality_cloning_model cloning_model,
double freq_cutoff, int size, int &cl_num,
int &npartitions, int64_t partition_size,
lto_locality_heuristics scheme)
{
/* Aliases are added in the same partition as their targets.
Aliases are not cloned and their callees are not processed separately. */
cgraph_node *cl_node = NULL;
if (partition->insns > partition_size)
partition = create_partition (npartitions);
/* Iterate over all unique callees of NODE, direct callees and callees via
inlined nodes. This avoids calling partition_callchain () separately for
inlined nodes which themselves are already partitioned along with their
inlined_to nodes. */
locality_info *info = get_locality_info (node);
if (scheme == LTO_LOCALITY_CPP_TEMPLATE)
info->all_callees.qsort (callee_templ_cmp);
for (unsigned i = 0; i < info->all_callees.length (); i++)
{
cgraph_edge *e = info->all_callees[i]->edge;
cgraph_node *n = e->callee->ultimate_alias_target ();
if (n->get_partitioning_class () == SYMBOL_PARTITION)
{
if (!node_partitioned_p (n))
{
add_node_to_partition (partition, n);
if (dump_file)
fprintf (dump_file, "Partitioned node: %s\n",
n->dump_asm_name ());
partition_callchain (n, partition, cloning_model, freq_cutoff,
size, cl_num, npartitions, partition_size,
scheme);
}
else if (cloning_model >= LTO_LOCALITY_NON_INTERPOSABLE_CLONING
&& (!e->callee->alias)
&& node_in_partition_p (partition, e->caller)
&& (!node_in_partition_p (partition, n)))
{
/* 3 possible scenarios if N is already partitioned but not in
present in PARTITION:
1. There's a clone of N present in PARTITION, redirect to that
clone, no need to check for suitability.
2. N itself is a locality clone, cloned as part of another
callchain. If a clone of N's original node is present in
PARTITION, redirect to it without checking for suitability.
Cloned node itself is not cloned again.
Example: suppose N = B_clone ().
In partition X, edge A->B was transformed to A->B_clone0.
In current partition, A was cloned to A_clone0 and now
B_clone0 is visited via edge A_clone0->B_clone0. If a
B_clonei is present, redirect A_clone0 to it, otherise do
nothing.
3. N is not a locality clone and no clone of N is present in
PARTITION, check for suitability and clone. */
cgraph_node *orig_cnode = n;
cgraph_node **o_cnode = clone_to_node->get (n->get_uid ());
if (o_cnode)
orig_cnode = *o_cnode;
cgraph_node **cnode_cl = node_to_clone->get (orig_cnode->get_uid
());
if ((cnode_cl && node_in_partition_p (partition, *cnode_cl))
|| (orig_cnode == n
&& clone_node_p (e, cloning_model, freq_cutoff, size)))
{
cl_node = clone_node_as_needed (e, partition, cl_num,
cloning_model);
if (cl_node)
{
create_locality_info (cl_node,
scheme == LTO_LOCALITY_CPP_TEMPLATE,
true);
add_node_to_partition (partition, cl_node);
partition_callchain (cl_node, partition, cloning_model,
freq_cutoff, size, cl_num,
npartitions, partition_size, scheme);
}
}
}
}
}
}
/* Determine whether NODE is an entrypoint to a callchain. */
static bool
is_entry_node_p (cgraph_node *node)
{
/* node->inlined_to is returned as SYMBOL_DUPLICATE. */
if (node->get_partitioning_class () != SYMBOL_PARTITION)
return false;
/* NODE and all its aliases or thunk are local. */
if (node->local_p ())
return false;
if (!node->callers)
return true;
for (cgraph_edge *e = node->callers; e; e = e->next_caller)
{
if (! e->recursive_p ())
return false;
}
return true;
}
/* Determine order of all external nodes if PGO profile is available.
Store the order in ORDER. */
static bool
locality_determine_ipa_order (auto_vec<locality_order *> *order)
{
struct cgraph_node *node;
auto_vec<locality_order *> non_comparable_nodes;
FOR_EACH_DEFINED_FUNCTION (node)
if (node->get_partitioning_class () == SYMBOL_PARTITION)
{
create_locality_info (node);
if (node->no_reorder)
{
if (dump_file)
fprintf (dump_file, "no reorder %s\n", node->dump_asm_name ());
return false;
}
else if (is_entry_node_p (node))
{
profile_count pcnt = node->count.ipa ();
if (!pcnt.initialized_p () || !pcnt.ipa_p ())
{
sreal cnt = 0;
locality_order *lo = new locality_order (node, cnt);
non_comparable_nodes.safe_push (lo);
continue;
}
sreal count = 0;
struct cgraph_edge *edge;
for (edge = node->callees; edge; edge = edge->next_callee)
{
/* For PGO, frequency is not used in
compare_edge_profile_counts (), it's used only as part of
static profile order. */
sreal freq = edge->sreal_frequency ();
count += freq;
}
locality_order *cl = new locality_order (node, count);
order->safe_push (cl);
}
}
order->qsort (compare_edge_profile_counts);
for (auto el : non_comparable_nodes)
order->safe_push (el);
return true;
}
/* Determine order of all external nodes if only static profile is available.
Store the order in ORDER. */
static bool
locality_determine_static_order (auto_vec<locality_order *> *order,
lto_locality_heuristics scheme)
{
struct cgraph_node *node;
FOR_EACH_DEFINED_FUNCTION (node)
if (node->get_partitioning_class () == SYMBOL_PARTITION)
{
create_locality_info (node, scheme == LTO_LOCALITY_CPP_TEMPLATE);
if (node->no_reorder)
{
if (dump_file)
fprintf (dump_file, "no reorder %s\n", node->dump_asm_name ());
return false;
}
else if (is_entry_node_p (node))
{
sreal count = 0;
struct cgraph_edge *edge;
for (edge = node->callees; edge; edge = edge->next_callee)
{
sreal freq = edge->sreal_frequency ();
count += freq;
}
locality_order *cl = new locality_order (node, count);
order->safe_push (cl);
}
}
if (scheme == LTO_LOCALITY_CPP_TEMPLATE)
{
order_templ_hashes ();
order->qsort (static_profile_templ_cmp);
return true;
}
order->qsort (static_profile_cmp);
return true;
}
/* Partitioning for code locality.
1. Create and sort callchains. If PGO is available, use real profile
counts. Otherwise, use a set of heuristics to sort the callchains.
2. Partition the external nodes and their callchains in the determined order
2.1. If !partition, partition, else try and clone if it satisfies cloning
criteria.
3. Partition all other unpartitioned nodes. */
static void
locality_partition_and_clone (int max_locality_partition_size,
lto_locality_cloning_model cloning_model,
lto_locality_heuristics scheme,
int freq_denominator, int size)
{
locality_partition partition;
int npartitions = 0;
auto_vec<locality_order *> order;
auto_vec<varpool_node *> varpool_order;
struct cgraph_node *node;
bool order_p;
int cl_num = 0;
double real_freq = 0.0;
if (freq_denominator > 0)
real_freq = 1.0 / (double) freq_denominator;
cgraph_node *n = symtab->first_defined_function ();
if (n && n->count.ipa_p ())
order_p = locality_determine_ipa_order (&order);
else
order_p = locality_determine_static_order (&order, scheme);
if (!order_p)
{
if (dump_file)
{
fprintf (dump_file, "Locality partition: falling back to balanced"
"model\n");
}
return;
}
int64_t partition_size
= max_locality_partition_size
? max_locality_partition_size : param_max_partition_size;
partition = create_partition (npartitions);
for (unsigned i = 0; i < order.length (); i++)
{
node = order[i]->node;
if (node_partitioned_p (node))
continue;
if (partition->insns > partition_size)
partition = create_partition (npartitions);
if (dump_file)
fprintf (dump_file, "Partition id: %d\n", partition->part_id);
add_node_to_partition (partition, node);
if (dump_file)
fprintf (dump_file, "Ordered Node: %s\n", node->dump_asm_name ());
partition_callchain (node, partition, cloning_model, real_freq, size,
cl_num, npartitions, partition_size, scheme);
}
for (unsigned i = 0; i < order.length (); i++)
delete order[i];
order = vNULL;
loc_infos.release ();
}
/* Entry point to locality-clone pass. */
static int
lc_execute (void)
{
symtab_node *node;
FOR_EACH_SYMBOL (node)
node->aux = NULL;
node_to_ch_info = std::make_unique<hash_map<loc_map_hash, locality_info *>>
();
node_to_clone = std::make_unique<hash_map<loc_map_hash, cgraph_node *>> ();
clone_to_node = std::make_unique<hash_map<loc_map_hash, cgraph_node *>> ();
templ_hash_map = std::make_unique<hash_freq_map_t> ();
locality_partition_and_clone (param_max_locality_partition_size,
flag_lto_locality_cloning,
flag_lto_locality_heuristics,
param_lto_locality_frequency,
param_lto_locality_size);
FOR_EACH_SYMBOL (node)
node->aux = NULL;
return 0;
}
namespace {
const pass_data pass_data_ipa_locality_clone = {
IPA_PASS, /* type */
"locality-clone", /* name */
OPTGROUP_NONE, /* optinfo_flags */
TV_IPA_LC, /* tv_id */
0, /* properties_required */
0, /* properties_provided */
0, /* properties_destroyed */
0, /* todo_flags_start */
(TODO_dump_symtab | TODO_remove_functions), /* todo_flags_finish */
};
class pass_ipa_locality_cloning : public ipa_opt_pass_d
{
public:
pass_ipa_locality_cloning (gcc::context *ctxt)
: ipa_opt_pass_d (pass_data_ipa_locality_clone, ctxt,
NULL, /* generate_summary */
NULL, /* write_summary */
NULL, /* read_summary */
NULL, /* write_optimization_summary */
NULL, /* read_optimization_summary */
NULL, /* stmt_fixup */
0, /* function_transform_todo_flags_start */
NULL, /* function_transform */
NULL) /* variable_transform */
{}
/* opt_pass methods: */
virtual bool gate (function *)
{
return (flag_wpa && flag_ipa_reorder_for_locality);
}
virtual unsigned int execute (function *) { return lc_execute (); }
}; // class pass_ipa_locality_cloning
} // namespace
ipa_opt_pass_d *
make_pass_ipa_locality_cloning (gcc::context *ctxt)
{
return new pass_ipa_locality_cloning (ctxt);
}