This reduces WPA memory usage at stream-out time by avoiding to
allocate the streamer cache node array and by freeing the global
out-decl-states hash tables (we do that already for the fn-decl-states).
LTO bootstrapped and bootstrapped on x86_64-unknown-linux-gnu, testing
in progress.
Ok?
Not sure if it will make a notable difference. The pointer-map
overhead is at least 4 times of that of the vector, if we make
pointer-map behave like hash_table (3/4 full) or htab_t
(half full) then that would improve (we could even make that
configurable at pointer-set/map construction time). Like with
Index: gcc/pointer-set.c
===================================================================
--- gcc/pointer-set.c (revision 209018)
+++ gcc/pointer-set.c (working copy)
@@ -125,7 +125,7 @@ pointer_set_insert (struct pointer_set_t
/* For simplicity, expand the set even if P is already there. This can
be
superfluous but can happen at most once. */
- if (pset->n_elements > pset->n_slots / 4)
+ if (pset->n_elements * 4 > pset->n_slots * 3)
{
size_t old_n_slots = pset->n_slots;
const void **old_slots = pset->slots;
Index: gcc/pointer-set.h
===================================================================
--- gcc/pointer-set.h (revision 209018)
+++ gcc/pointer-set.h (working copy)
@@ -109,7 +109,7 @@ pointer_map<T>::insert (const void *p, b
/* For simplicity, expand the map even if P is already there. This can
be
superfluous but can happen at most once. */
/* ??? Fugly that we have to inline that here. */
- if (n_elements > n_slots / 4)
+ if (n_elements * 4 > n_slots * 3)
{
size_t old_n_slots = n_slots;
const void **old_keys = slots;
might be worth checking how much memory we save from the above.
Thanks,
Richard.
2014-04-03 Richard Biener <rguent...@suse.de>
* tree-streamer.h (struct streamer_tree_cache_d): Add next_idx
member.
(streamer_tree_cache_create): Adjust.
* tree-streamer.c (streamer_tree_cache_add_to_node_array): Adjust
to allow optional nodes array.
(streamer_tree_cache_insert_1): Use next_idx to assign idx.
(streamer_tree_cache_append): Likewise.
(streamer_tree_cache_create): Create nodes array optionally
as specified by parameter.
* lto-streamer-out.c (create_output_block): Avoid maintaining
the node array in the writer cache.
(DFS_write_tree): Remove assertion.
(produce_asm_for_decls): Free the out decl state hash table
early.
* lto-streamer-in.c (lto_data_in_create): Adjust for
streamer_tree_cache_create prototype change.
Index: gcc/tree-streamer.c
===================================================================
*** gcc/tree-streamer.c (revision 209018)
--- gcc/tree-streamer.c (working copy)
*************** static void
*** 101,120 ****
streamer_tree_cache_add_to_node_array (struct streamer_tree_cache_d *cache,
unsigned ix, tree t, hashval_t hash)
{
! /* Make sure we're either replacing an old element or
! appending consecutively. */
! gcc_assert (ix <= cache->nodes.length ());
!
! if (ix == cache->nodes.length ())
{
! cache->nodes.safe_push (t);
! if (cache->hashes.exists ())
! cache->hashes.safe_push (hash);
}
! else
{
! cache->nodes[ix] = t;
! if (cache->hashes.exists ())
cache->hashes[ix] = hash;
}
}
--- 101,119 ----
streamer_tree_cache_add_to_node_array (struct streamer_tree_cache_d *cache,
unsigned ix, tree t, hashval_t hash)
{
! /* We're either replacing an old element or appending consecutively. */
! if (cache->nodes.exists ())
{
! if (cache->nodes.length () == ix)
! cache->nodes.safe_push (t);
! else
! cache->nodes[ix] = t;
}
! if (cache->hashes.exists ())
{
! if (cache->hashes.length () == ix)
! cache->hashes.safe_push (hash);
! else
cache->hashes[ix] = hash;
}
}
*************** streamer_tree_cache_insert_1 (struct str
*** 146,152 ****
{
/* Determine the next slot to use in the cache. */
if (insert_at_next_slot_p)
! ix = cache->nodes.length ();
else
ix = *ix_p;
*slot = ix;
--- 145,151 ----
{
/* Determine the next slot to use in the cache. */
if (insert_at_next_slot_p)
! ix = cache->next_idx++;
else
ix = *ix_p;
*slot = ix;
*************** void
*** 211,217 ****
streamer_tree_cache_append (struct streamer_tree_cache_d *cache,
tree t, hashval_t hash)
{
! unsigned ix = cache->nodes.length ();
if (!cache->node_map)
streamer_tree_cache_add_to_node_array (cache, ix, t, hash);
else
--- 210,216 ----
streamer_tree_cache_append (struct streamer_tree_cache_d *cache,
tree t, hashval_t hash)
{
! unsigned ix = cache->next_idx++;
if (!cache->node_map)
streamer_tree_cache_add_to_node_array (cache, ix, t, hash);
else
*************** preload_common_nodes (struct streamer_tr
*** 326,332 ****
/* Create a cache of pickled nodes. */
struct streamer_tree_cache_d *
! streamer_tree_cache_create (bool with_hashes, bool with_map)
{
struct streamer_tree_cache_d *cache;
--- 325,331 ----
/* Create a cache of pickled nodes. */
struct streamer_tree_cache_d *
! streamer_tree_cache_create (bool with_hashes, bool with_map, bool with_vec)
{
struct streamer_tree_cache_d *cache;
*************** streamer_tree_cache_create (bool with_ha
*** 334,340 ****
if (with_map)
cache->node_map = new pointer_map<unsigned>;
! cache->nodes.create (165);
if (with_hashes)
cache->hashes.create (165);
--- 333,341 ----
if (with_map)
cache->node_map = new pointer_map<unsigned>;
! cache->next_idx = 0;
! if (with_vec)
! cache->nodes.create (165);
if (with_hashes)
cache->hashes.create (165);
Index: gcc/tree-streamer.h
===================================================================
*** gcc/tree-streamer.h (revision 209018)
--- gcc/tree-streamer.h (working copy)
*************** struct streamer_tree_cache_d
*** 52,57 ****
--- 52,60 ----
vec<tree> nodes;
/* The node hashes (if available). */
vec<hashval_t> hashes;
+
+ /* Next index to assign. */
+ unsigned next_idx;
};
/* Return true if tree node EXPR should be streamed as a builtin. For
*************** void streamer_tree_cache_append (struct
*** 97,103 ****
hashval_t);
bool streamer_tree_cache_lookup (struct streamer_tree_cache_d *, tree,
unsigned *);
! struct streamer_tree_cache_d *streamer_tree_cache_create (bool, bool);
void streamer_tree_cache_delete (struct streamer_tree_cache_d *);
/* Return the tree node at slot IX in CACHE. */
--- 100,106 ----
hashval_t);
bool streamer_tree_cache_lookup (struct streamer_tree_cache_d *, tree,
unsigned *);
! struct streamer_tree_cache_d *streamer_tree_cache_create (bool, bool, bool);
void streamer_tree_cache_delete (struct streamer_tree_cache_d *);
/* Return the tree node at slot IX in CACHE. */
Index: gcc/lto-streamer-out.c
===================================================================
*** gcc/lto-streamer-out.c (revision 209018)
--- gcc/lto-streamer-out.c (working copy)
*************** create_output_block (enum lto_section_ty
*** 79,85 ****
ob->decl_state = lto_get_out_decl_state ();
ob->main_stream = XCNEW (struct lto_output_stream);
ob->string_stream = XCNEW (struct lto_output_stream);
! ob->writer_cache = streamer_tree_cache_create (!flag_wpa, true);
if (section_type == LTO_section_function_body)
ob->cfg_stream = XCNEW (struct lto_output_stream);
--- 79,85 ----
ob->decl_state = lto_get_out_decl_state ();
ob->main_stream = XCNEW (struct lto_output_stream);
ob->string_stream = XCNEW (struct lto_output_stream);
! ob->writer_cache = streamer_tree_cache_create (!flag_wpa, true, false);
if (section_type == LTO_section_function_body)
ob->cfg_stream = XCNEW (struct lto_output_stream);
*************** DFS_write_tree (struct output_block *ob,
*** 1277,1283 ****
??? We still wrap these in LTO_tree_scc so at the
input side we can properly identify the tree we want
to ultimatively return. */
- size_t old_len = ob->writer_cache->nodes.length ();
if (size == 1)
lto_output_tree_1 (ob, expr, scc_hash, ref_p, this_ref_p);
else
--- 1277,1282 ----
*************** DFS_write_tree (struct output_block *ob,
*** 1315,1321 ****
streamer_write_zero (ob);
}
}
- gcc_assert (old_len + size == ob->writer_cache->nodes.length ());
/* Finally truncate the vector. */
sccstack.truncate (first);
--- 1314,1319 ----
*************** produce_asm_for_decls (void)
*** 2423,2432 ****
gcc_assert (!alias_pairs);
! /* Write the global symbols. */
out_state = lto_get_out_decl_state ();
! num_fns = lto_function_decl_states.length ();
lto_output_decl_state_streams (ob, out_state);
for (idx = 0; idx < num_fns; idx++)
{
fn_out_state =
--- 2453,2470 ----
gcc_assert (!alias_pairs);
! /* Get rid of the global decl state hash tables to save some memory. */
out_state = lto_get_out_decl_state ();
! for (int i = 0; i < LTO_N_DECL_STREAMS; i++)
! if (out_state->streams[i].tree_hash_table)
! {
! delete out_state->streams[i].tree_hash_table;
! out_state->streams[i].tree_hash_table = NULL;
! }
!
! /* Write the global symbols. */
lto_output_decl_state_streams (ob, out_state);
+ num_fns = lto_function_decl_states.length ();
for (idx = 0; idx < num_fns; idx++)
{
fn_out_state =
Index: gcc/lto-streamer-in.c
===================================================================
*** gcc/lto-streamer-in.c (revision 209018)
--- gcc/lto-streamer-in.c (working copy)
*************** lto_data_in_create (struct lto_file_decl
*** 1365,1372 ****
data_in->strings = strings;
data_in->strings_len = len;
data_in->globals_resolution = resolutions;
! data_in->reader_cache = streamer_tree_cache_create (false, false);
!
return data_in;
}
--- 1365,1371 ----
data_in->strings = strings;
data_in->strings_len = len;
data_in->globals_resolution = resolutions;
! data_in->reader_cache = streamer_tree_cache_create (false, false, true);
return data_in;
}
