Hi,
we spend a lot of effort (and disk space) into streaming file/line/column and
sys_p fields of locations. Since often the trees come from same statement, it
is common for those to not change. We even already have current location info
in output_block and data_in, but don't use it.
This patch update streaming to stream first bitpack of what changed and then
streaming only the changed locations. Because I did not find any use of
insys_p field in the backend, I removed streaming it (though it would be easy
doable to stream it along the file info).
Because we need only 4 bits, it would make a lot of sense to merge location
bitpack with the other bitpack and for this reason I split the i/o intput part
doing bitpack and part streaming the actual data. At the moment we always do
that at once, since doing anything saner needs a bit of reorganization of how
we stream trees.
Regtested x86_64-linux, full bootstrap®test running, OK?
Honza
* lto-streamer-out.c (clear_line_info): Set location_output_done.
(lto_output_location_bitpack): New function.
(lto_output_location_data): New function.
(lto_output_location): Reorg.
* lto-streamer-in.c (clear_line_info): Set location_input_done.
(lto_input_location_bitpack): New function.
(lto_input_location_data): New function.
(lto_input_location): Reorg.
* lto-streamer.h (struct output_block): Add output_file, output_line,
output_col and location_output_done flags.
(struct data_in): Add input_file, input_line, input_col and
location_input_done flags.
Index: lto-streamer-out.c
===================================================================
--- lto-streamer-out.c (revision 174264)
+++ lto-streamer-out.c (working copy)
@@ -95,6 +95,7 @@ clear_line_info (struct output_block *ob
ob->current_file = NULL;
ob->current_line = 0;
ob->current_col = 0;
+ ob->location_output_done = 1;
}
@@ -587,29 +588,72 @@ pack_value_fields (struct bitpack_d *bp,
}
-/* Emit location LOC to output block OB. */
+/* Output info about new location into bitpack BP.
+ After outputting bitpack, lto_output_location_data has
+ to be done to output actual data. */
+
+static inline void
+lto_output_location_bitpack (struct bitpack_d *bp,
+ struct output_block *ob,
+ location_t loc)
+{
+ gcc_checking_assert (ob->location_output_done);
+ bp_pack_value (bp, loc == UNKNOWN_LOCATION, 1);
+ if (loc == UNKNOWN_LOCATION)
+ ob->output_file = ob->output_line = ob->output_col = 0;
+ else
+ {
+ expanded_location xloc;
+
+ xloc = expand_location (loc);
+
+ ob->output_file = xloc.file != ob->current_file;
+ ob->output_line = xloc.line != ob->current_line;
+ ob->output_col = xloc.column != ob->current_col;
+ }
+ bp_pack_value (bp, ob->output_file, 1);
+ bp_pack_value (bp, ob->output_line, 1);
+ bp_pack_value (bp, ob->output_col, 1);
+ ob->location_output_done = false;
+}
+
+
+/* Output location info we prepared to output in
+ lto_output_location_bitpack */
static void
-lto_output_location (struct output_block *ob, location_t loc)
+lto_output_location_data (struct output_block *ob)
{
- expanded_location xloc;
+ gcc_checking_assert (!ob->location_output_done);
- if (loc == UNKNOWN_LOCATION)
+ if (ob->output_file)
+ lto_output_string (ob, ob->main_stream, ob->current_file);
+ if (ob->output_line)
{
- lto_output_string (ob, ob->main_stream, NULL);
- return;
+ gcc_checking_assert (ob->current_line >= 0);
+ output_uleb128 (ob, ob->current_line);
}
+ if (ob->output_col)
+ {
+ gcc_checking_assert (ob->current_col >= 0);
+ output_uleb128 (ob, ob->current_col);
+ }
+ ob->location_output_done = true;
+}
- xloc = expand_location (loc);
- lto_output_string (ob, ob->main_stream, xloc.file);
- output_sleb128 (ob, xloc.line);
- output_sleb128 (ob, xloc.column);
- output_sleb128 (ob, xloc.sysp);
-
- ob->current_file = xloc.file;
- ob->current_line = xloc.line;
- ob->current_col = xloc.column;
+/* Emit location LOC to output block OB.
+ When bitpack is handy, it is more space effecient to call
+ lto_output_location_bitpack and lto_output_location_data directly
+ adding info into the existing bitpack. */
+
+static void
+lto_output_location (struct output_block *ob, location_t loc)
+{
+ struct bitpack_d bp = bitpack_create (ob->main_stream);
+ lto_output_location_bitpack (&bp, ob, loc);
+ lto_output_bitpack (&bp);
+ lto_output_location_data (ob);
}
@@ -642,7 +686,7 @@ lto_output_tree_ref (struct output_block
if (expr == NULL_TREE)
{
- output_zero (ob);
+ output_record_start (ob, LTO_null);
return;
}
Index: lto-streamer-in.c
===================================================================
--- lto-streamer-in.c (revision 174264)
+++ lto-streamer-in.c (working copy)
@@ -281,40 +281,69 @@ clear_line_info (struct data_in *data_in
data_in->current_file = NULL;
data_in->current_line = 0;
data_in->current_col = 0;
+ data_in->location_input_done = true;
}
-/* Read a location from input block IB. */
+/* Read a location bitpack from input block IB. */
+
+static inline void
+lto_input_location_bitpack (struct data_in *data_in, struct bitpack_d *bp)
+{
+ gcc_checking_assert (data_in->location_input_done);
+ data_in->location_input_done = false;
+ data_in->input_unknown_location = bp_unpack_value (bp, 1);
+ data_in->input_file_p = bp_unpack_value (bp, 1);
+ data_in->input_line_p = bp_unpack_value (bp, 1);
+ data_in->input_col_p = bp_unpack_value (bp, 1);
+}
+
+
+/* Read locaiton data we determined to change and update info. */
static location_t
-lto_input_location (struct lto_input_block *ib, struct data_in *data_in)
+lto_input_location_data (struct lto_input_block *ib, struct data_in *data_in)
{
- expanded_location xloc;
+ bool prev_file = data_in->current_file != NULL;
- xloc.file = lto_input_string (data_in, ib);
- if (xloc.file == NULL)
+ gcc_checking_assert (!data_in->location_input_done);
+ data_in->location_input_done = true;
+ if (data_in->input_unknown_location)
return UNKNOWN_LOCATION;
+ if (data_in->input_file_p)
+ {
+ data_in->current_file = lto_input_string (data_in, ib);
+ data_in->current_file = canon_file_name (data_in->current_file);
+ }
+ if (data_in->input_line_p)
+ data_in->current_line = lto_input_uleb128 (ib);
+ if (data_in->input_col_p)
+ data_in->current_col = lto_input_uleb128 (ib);
- xloc.file = canon_file_name (xloc.file);
- xloc.line = lto_input_sleb128 (ib);
- xloc.column = lto_input_sleb128 (ib);
- xloc.sysp = lto_input_sleb128 (ib);
-
- if (data_in->current_file != xloc.file)
+ if (data_in->input_file_p)
{
- if (data_in->current_file)
+ if (prev_file)
linemap_add (line_table, LC_LEAVE, false, NULL, 0);
- linemap_add (line_table, LC_ENTER, xloc.sysp, xloc.file, xloc.line);
+ linemap_add (line_table, LC_ENTER, false, data_in->current_file,
data_in->current_line);
}
- else if (data_in->current_line != xloc.line)
- linemap_line_start (line_table, xloc.line, xloc.column);
+ else if (data_in->input_line_p)
+ linemap_line_start (line_table, data_in->current_line,
data_in->current_col);
- data_in->current_file = xloc.file;
- data_in->current_line = xloc.line;
- data_in->current_col = xloc.column;
+ return linemap_position_for_column (line_table, data_in->current_col);
+}
+
+
+/* Read a location from input block IB. */
+
+static location_t
+lto_input_location (struct lto_input_block *ib, struct data_in *data_in)
+{
+ struct bitpack_d bp;
- return linemap_position_for_column (line_table, xloc.column);
+ bp = lto_input_bitpack (ib);
+ lto_input_location_bitpack (data_in, &bp);
+ return lto_input_location_data (ib, data_in);
}
Index: lto-streamer.h
===================================================================
--- lto-streamer.h (revision 174264)
+++ lto-streamer.h (working copy)
@@ -694,6 +694,10 @@ struct output_block
const char *current_file;
int current_line;
int current_col;
+ unsigned output_file : 1;
+ unsigned output_line : 1;
+ unsigned output_col : 1;
+ unsigned location_output_done : 1;
/* True if writing globals and types. */
bool global;
@@ -728,6 +732,11 @@ struct data_in
const char *current_file;
int current_line;
int current_col;
+ unsigned input_unknown_location : 1;
+ unsigned input_file_p : 1;
+ unsigned input_line_p : 1;
+ unsigned input_col_p : 1;
+ unsigned location_input_done : 1;
/* Maps each reference number to the resolution done by the linker. */
VEC(ld_plugin_symbol_resolution_t,heap) *globals_resolution;
