Implement N disk counters for single value and indirect call counters.

2019-06-10  Martin Liska  <mliska@suse.cz>

	* gcov-io.h (GCOV_DISK_SINGLE_VALUES): New.
	(GCOV_SINGLE_VALUE_COUNTERS): Likewise.
	* ipa-profile.c (ipa_profile_generate_summary):
	Use get_most_common_single_value.
	* tree-profile.c (gimple_init_gcov_profiler):
	Instrument with __gcov_one_value_profiler_v2
	and __gcov_indirect_call_profiler_v4.
	* value-prof.c (dump_histogram_value):
	Print all values for HIST_TYPE_SINGLE_VALUE.
	(stream_out_histogram_value): Update assert for
	N values.
	(stream_in_histogram_value): Set number of
	counters for HIST_TYPE_SINGLE_VALUE.
	(get_most_common_single_value): New.
	(gimple_divmod_fixed_value_transform):
	Use get_most_common_single_value.
	(gimple_ic_transform): Likewise.
	(gimple_stringops_transform): Likewise.
	(gimple_find_values_to_profile): Set number
	of counters for HIST_TYPE_SINGLE_VALUE.
	* value-prof.h (get_most_common_single_value):
	New.
2019-06-10  Martin Liska  <mliska@suse.cz>

	* Makefile.in: Add __gcov_one_value_profiler_v2,
	__gcov_one_value_profiler_v2_atomic and
	__gcov_indirect_call_profiler_v4.
	* libgcov-merge.c (__gcov_merge_single): Change
	function signature.
	(merge_single_value_set): New.
	* libgcov-profiler.c (__gcov_one_value_profiler_body):
	Update functionality.
	(__gcov_one_value_profiler): Remove.
	(__gcov_one_value_profiler_v2): ... this.
	(__gcov_one_value_profiler_atomic): Rename to ...
	(__gcov_one_value_profiler_v2_atomic): this.
	(__gcov_indirect_call_profiler_v3): Rename to ...
	(__gcov_indirect_call_profiler_v4): ... this.
	* libgcov.h (__gcov_one_value_profiler): Remove.
	(__gcov_one_value_profiler_atomic): Remove.
	(__gcov_one_value_profiler_v2_atomic): New.
	(__gcov_indirect_call_profiler_v3): Remove.
	(__gcov_one_value_profiler_v2): New.
	(__gcov_indirect_call_profiler_v4): New.
	(gcov_get_counter_ignore_scaling): New function.

From-SVN: r272106
This commit is contained in:
Martin Liska 2019-06-10 09:38:59 +02:00 committed by Martin Liska
parent b076a52602
commit 92d417175b
11 changed files with 249 additions and 116 deletions

View File

@ -1,3 +1,28 @@
2019-06-10 Martin Liska <mliska@suse.cz>
* gcov-io.h (GCOV_DISK_SINGLE_VALUES): New.
(GCOV_SINGLE_VALUE_COUNTERS): Likewise.
* ipa-profile.c (ipa_profile_generate_summary):
Use get_most_common_single_value.
* tree-profile.c (gimple_init_gcov_profiler):
Instrument with __gcov_one_value_profiler_v2
and __gcov_indirect_call_profiler_v4.
* value-prof.c (dump_histogram_value):
Print all values for HIST_TYPE_SINGLE_VALUE.
(stream_out_histogram_value): Update assert for
N values.
(stream_in_histogram_value): Set number of
counters for HIST_TYPE_SINGLE_VALUE.
(get_most_common_single_value): New.
(gimple_divmod_fixed_value_transform):
Use get_most_common_single_value.
(gimple_ic_transform): Likewise.
(gimple_stringops_transform): Likewise.
(gimple_find_values_to_profile): Set number
of counters for HIST_TYPE_SINGLE_VALUE.
* value-prof.h (get_most_common_single_value):
New.
2019-06-10 Martin Liska <mliska@suse.cz>
* hash-map.h: Pass default value to hash_table ctor.

View File

@ -266,6 +266,13 @@ GCOV_COUNTERS
#define GCOV_N_VALUE_COUNTERS \
(GCOV_LAST_VALUE_COUNTER - GCOV_FIRST_VALUE_COUNTER + 1)
/* Number of single value histogram values that live
on disk representation. */
#define GCOV_DISK_SINGLE_VALUES 4
/* Total number of single value counters. */
#define GCOV_SINGLE_VALUE_COUNTERS (2 * GCOV_DISK_SINGLE_VALUES + 1)
/* Convert a counter index to a tag. */
#define GCOV_TAG_FOR_COUNTER(COUNT) \
(GCOV_TAG_COUNTER_BASE + ((gcov_unsigned_t)(COUNT) << 17))

View File

@ -191,17 +191,17 @@ ipa_profile_generate_summary (void)
takes away bad histograms. */
if (h)
{
/* counter 0 is target, counter 1 is number of execution we called target,
counter 2 is total number of executions. */
if (h->hvalue.counters[2])
gcov_type val, count, all;
if (get_most_common_single_value (NULL, "indirect call",
h, &val, &count, &all))
{
struct cgraph_edge * e = node->get_edge (stmt);
if (e && !e->indirect_unknown_callee)
continue;
e->indirect_info->common_target_id
= h->hvalue.counters [0];
e->indirect_info->common_target_id = val;
e->indirect_info->common_target_probability
= GCOV_COMPUTE_SCALE (h->hvalue.counters [1], h->hvalue.counters [2]);
= GCOV_COMPUTE_SCALE (count, all);
if (e->indirect_info->common_target_probability > REG_BR_PROB_BASE)
{
if (dump_file)

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@ -165,10 +165,10 @@ gimple_init_gcov_profiler (void)
= build_function_type_list (void_type_node,
gcov_type_ptr, gcov_type_node,
NULL_TREE);
fn_name = concat ("__gcov_one_value_profiler", fn_suffix, NULL);
fn_name = concat ("__gcov_one_value_profiler_v2", fn_suffix, NULL);
tree_one_value_profiler_fn = build_fn_decl (fn_name,
one_value_profiler_fn_type);
free (CONST_CAST (char *, fn_name));
TREE_NOTHROW (tree_one_value_profiler_fn) = 1;
DECL_ATTRIBUTES (tree_one_value_profiler_fn)
= tree_cons (get_identifier ("leaf"), NULL,
@ -182,7 +182,7 @@ gimple_init_gcov_profiler (void)
gcov_type_node,
ptr_type_node,
NULL_TREE);
profiler_fn_name = "__gcov_indirect_call_profiler_v3";
profiler_fn_name = "__gcov_indirect_call_profiler_v4";
tree_indirect_call_profiler_fn
= build_fn_decl (profiler_fn_name, ic_profiler_fn_type);

View File

@ -259,15 +259,22 @@ dump_histogram_value (FILE *dump_file, histogram_value hist)
break;
case HIST_TYPE_SINGLE_VALUE:
fprintf (dump_file, "Single value ");
case HIST_TYPE_INDIR_CALL:
fprintf (dump_file,
(hist->type == HIST_TYPE_SINGLE_VALUE
? "Single value counter " : "Indirect call counter"));
if (hist->hvalue.counters)
{
fprintf (dump_file, "value:%" PRId64
" match:%" PRId64
" wrong:%" PRId64,
(int64_t) hist->hvalue.counters[0],
(int64_t) hist->hvalue.counters[1],
(int64_t) hist->hvalue.counters[2]);
fprintf (dump_file, "all: %" PRId64 ", values: ",
(int64_t) hist->hvalue.counters[0]);
for (unsigned i = 0; i < GCOV_DISK_SINGLE_VALUES; i++)
{
fprintf (dump_file, "[%" PRId64 ":%" PRId64 "]",
(int64_t) hist->hvalue.counters[2 * i + 1],
(int64_t) hist->hvalue.counters[2 * i + 2]);
if (i != GCOV_DISK_SINGLE_VALUES - 1)
fprintf (dump_file, ", ");
}
}
fprintf (dump_file, ".\n");
break;
@ -294,19 +301,6 @@ dump_histogram_value (FILE *dump_file, histogram_value hist)
fprintf (dump_file, ".\n");
break;
case HIST_TYPE_INDIR_CALL:
fprintf (dump_file, "Indirect call ");
if (hist->hvalue.counters)
{
fprintf (dump_file, "value:%" PRId64
" match:%" PRId64
" all:%" PRId64,
(int64_t) hist->hvalue.counters[0],
(int64_t) hist->hvalue.counters[1],
(int64_t) hist->hvalue.counters[2]);
}
fprintf (dump_file, ".\n");
break;
case HIST_TYPE_TIME_PROFILE:
fprintf (dump_file, "Time profile ");
if (hist->hvalue.counters)
@ -347,7 +341,7 @@ stream_out_histogram_value (struct output_block *ob, histogram_value hist)
/* When user uses an unsigned type with a big value, constant converted
to gcov_type (a signed type) can be negative. */
gcov_type value = hist->hvalue.counters[i];
if (hist->type == HIST_TYPE_SINGLE_VALUE && i == 0)
if (hist->type == HIST_TYPE_SINGLE_VALUE && (i > 0 && ((i - 1) % 2) == 0))
;
else
gcc_assert (value >= 0);
@ -392,7 +386,7 @@ stream_in_histogram_value (struct lto_input_block *ib, gimple *stmt)
case HIST_TYPE_SINGLE_VALUE:
case HIST_TYPE_INDIR_CALL:
ncounters = 3;
ncounters = GCOV_SINGLE_VALUE_COUNTERS;
break;
case HIST_TYPE_IOR:
@ -729,6 +723,48 @@ gimple_divmod_fixed_value (gassign *stmt, tree value, profile_probability prob,
return tmp2;
}
/* Return most common value of SINGLE_VALUE histogram. If
there's a unique value, return true and set VALUE and COUNT
arguments. */
bool
get_most_common_single_value (gimple *stmt, const char *counter_type,
histogram_value hist,
gcov_type *value, gcov_type *count,
gcov_type *all)
{
if (hist->hvalue.counters[2] == -1)
return false;
*count = 0;
*value = 0;
gcov_type read_all = hist->hvalue.counters[0];
for (unsigned i = 0; i < GCOV_DISK_SINGLE_VALUES; i++)
{
gcov_type v = hist->hvalue.counters[2 * i + 1];
gcov_type c = hist->hvalue.counters[2 * i + 2];
/* Indirect calls can't be vereified. */
if (stmt && check_counter (stmt, counter_type, &c, &read_all,
gimple_bb (stmt)->count))
return false;
*all = read_all;
if (c > *count)
{
*value = v;
*count = c;
}
else if (c == *count && v > *value)
*value = v;
}
return true;
}
/* Do transform 1) on INSN if applicable. */
static bool
@ -758,23 +794,19 @@ gimple_divmod_fixed_value_transform (gimple_stmt_iterator *si)
if (!histogram)
return false;
if (!get_most_common_single_value (stmt, "divmod", histogram, &val, &count,
&all))
return false;
value = histogram->hvalue.value;
val = histogram->hvalue.counters[0];
count = histogram->hvalue.counters[1];
all = histogram->hvalue.counters[2];
gimple_remove_histogram_value (cfun, stmt, histogram);
/* We require that count is at least half of all; this means
that for the transformation to fire the value must be constant
at least 50% of time (and 75% gives the guarantee of usage). */
/* We require that count is at least half of all. */
if (simple_cst_equal (gimple_assign_rhs2 (stmt), value) != 1
|| 2 * count < all
|| optimize_bb_for_size_p (gimple_bb (stmt)))
return false;
if (check_counter (stmt, "value", &count, &all, gimple_bb (stmt)->count))
return false;
/* Compute probability of taking the optimal path. */
if (all > 0)
prob = profile_probability::probability_in_gcov_type (count, all);
@ -1401,7 +1433,7 @@ gimple_ic_transform (gimple_stmt_iterator *gsi)
{
gcall *stmt;
histogram_value histogram;
gcov_type val, count, all, bb_all;
gcov_type val, count, all;
struct cgraph_node *direct_call;
stmt = dyn_cast <gcall *> (gsi_stmt (*gsi));
@ -1418,21 +1450,9 @@ gimple_ic_transform (gimple_stmt_iterator *gsi)
if (!histogram)
return false;
val = histogram->hvalue.counters [0];
count = histogram->hvalue.counters [1];
all = histogram->hvalue.counters [2];
bb_all = gimple_bb (stmt)->count.ipa ().to_gcov_type ();
/* The order of CHECK_COUNTER calls is important -
since check_counter can correct the third parameter
and we want to make count <= all <= bb_all. */
if (check_counter (stmt, "ic", &all, &bb_all, gimple_bb (stmt)->count)
|| check_counter (stmt, "ic", &count, &all,
profile_count::from_gcov_type (all)))
{
gimple_remove_histogram_value (cfun, stmt, histogram);
return false;
}
if (!get_most_common_single_value (NULL, "indirect call", histogram, &val,
&count, &all))
return false;
if (4 * count <= 3 * all)
return false;
@ -1644,19 +1664,19 @@ gimple_stringops_transform (gimple_stmt_iterator *gsi)
if (TREE_CODE (blck_size) == INTEGER_CST)
return false;
histogram = gimple_histogram_value_of_type (cfun, stmt, HIST_TYPE_SINGLE_VALUE);
histogram = gimple_histogram_value_of_type (cfun, stmt,
HIST_TYPE_SINGLE_VALUE);
if (!histogram)
return false;
val = histogram->hvalue.counters[0];
count = histogram->hvalue.counters[1];
all = histogram->hvalue.counters[2];
if (!get_most_common_single_value (stmt, "stringops", histogram, &val,
&count, &all))
return false;
gimple_remove_histogram_value (cfun, stmt, histogram);
/* We require that count is at least half of all; this means
that for the transformation to fire the value must be constant
at least 80% of time. */
if ((6 * count / 5) < all || optimize_bb_for_size_p (gimple_bb (stmt)))
/* We require that count is at least half of all. */
if (2 * count < all || optimize_bb_for_size_p (gimple_bb (stmt)))
return false;
if (check_counter (stmt, "value", &count, &all, gimple_bb (stmt)->count))
return false;
@ -1928,11 +1948,11 @@ gimple_find_values_to_profile (histogram_values *values)
break;
case HIST_TYPE_SINGLE_VALUE:
hist->n_counters = 3;
hist->n_counters = GCOV_SINGLE_VALUE_COUNTERS;
break;
case HIST_TYPE_INDIR_CALL:
hist->n_counters = 3;
case HIST_TYPE_INDIR_CALL:
hist->n_counters = GCOV_SINGLE_VALUE_COUNTERS;
break;
case HIST_TYPE_TIME_PROFILE:

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@ -90,6 +90,10 @@ void free_histograms (function *);
void stringop_block_profile (gimple *, unsigned int *, HOST_WIDE_INT *);
gcall *gimple_ic (gcall *, struct cgraph_node *, profile_probability);
bool check_ic_target (gcall *, struct cgraph_node *);
bool get_most_common_single_value (gimple *stmt, const char *counter_type,
histogram_value hist,
gcov_type *value, gcov_type *count,
gcov_type *all);
/* In tree-profile.c. */

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@ -1,3 +1,27 @@
2019-06-10 Martin Liska <mliska@suse.cz>
* Makefile.in: Add __gcov_one_value_profiler_v2,
__gcov_one_value_profiler_v2_atomic and
__gcov_indirect_call_profiler_v4.
* libgcov-merge.c (__gcov_merge_single): Change
function signature.
(merge_single_value_set): New.
* libgcov-profiler.c (__gcov_one_value_profiler_body):
Update functionality.
(__gcov_one_value_profiler): Remove.
(__gcov_one_value_profiler_v2): ... this.
(__gcov_one_value_profiler_atomic): Rename to ...
(__gcov_one_value_profiler_v2_atomic): this.
(__gcov_indirect_call_profiler_v3): Rename to ...
(__gcov_indirect_call_profiler_v4): ... this.
* libgcov.h (__gcov_one_value_profiler): Remove.
(__gcov_one_value_profiler_atomic): Remove.
(__gcov_one_value_profiler_v2_atomic): New.
(__gcov_indirect_call_profiler_v3): Remove.
(__gcov_one_value_profiler_v2): New.
(__gcov_indirect_call_profiler_v4): New.
(gcov_get_counter_ignore_scaling): New function.
2019-06-07 Martin Liska <mliska@suse.cz>
* Makefile.in: Remove usage of

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@ -893,13 +893,13 @@ LIBGCOV_PROFILER = _gcov_interval_profiler \
_gcov_interval_profiler_atomic \
_gcov_pow2_profiler \
_gcov_pow2_profiler_atomic \
_gcov_one_value_profiler \
_gcov_one_value_profiler_atomic \
_gcov_one_value_profiler_v2 \
_gcov_one_value_profiler_v2_atomic \
_gcov_average_profiler \
_gcov_average_profiler_atomic \
_gcov_ior_profiler \
_gcov_ior_profiler_atomic \
_gcov_indirect_call_profiler_v3 \
_gcov_indirect_call_profiler_v4 \
_gcov_time_profiler
LIBGCOV_INTERFACE = _gcov_dump _gcov_flush _gcov_fork \
_gcov_execl _gcov_execlp \

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@ -34,8 +34,9 @@ void __gcov_merge_add (gcov_type *counters __attribute__ ((unused)),
#endif
#ifdef L_gcov_merge_single
void __gcov_merge_single (gcov_type *counters __attribute__ ((unused)),
unsigned n_counters __attribute__ ((unused))) {}
void __gcov_merge_single (gcov_type *counters __attribute__ ((unused)))
{
}
#endif
#else
@ -85,40 +86,72 @@ __gcov_merge_time_profile (gcov_type *counters, unsigned n_counters)
#endif /* L_gcov_merge_time_profile */
#ifdef L_gcov_merge_single
static void
merge_single_value_set (gcov_type *counters)
{
unsigned j;
gcov_type value, counter;
/* First value is number of total executions of the profiler. */
gcov_type all = gcov_get_counter_ignore_scaling (-1);
counters[0] += all;
++counters;
for (unsigned i = 0; i < GCOV_DISK_SINGLE_VALUES; i++)
{
value = gcov_get_counter_target ();
counter = gcov_get_counter_ignore_scaling (-1);
if (counter == -1)
{
counters[1] = -1;
/* We can't return as we need to read all counters. */
continue;
}
else if (counter == 0 || counters[1] == -1)
{
/* We can't return as we need to read all counters. */
continue;
}
for (j = 0; j < GCOV_DISK_SINGLE_VALUES; j++)
{
if (counters[2 * j] == value)
{
counters[2 * j + 1] += counter;
break;
}
else if (counters[2 * j + 1] == 0)
{
counters[2 * j] = value;
counters[2 * j + 1] = counter;
break;
}
}
/* We haven't found a free slot for the value, mark overflow. */
if (j == GCOV_DISK_SINGLE_VALUES)
counters[1] = -1;
}
}
/* The profile merging function for choosing the most common value.
It is given an array COUNTERS of N_COUNTERS old counters and it
reads the same number of counters from the gcov file. The counters
are split into 3-tuples where the members of the tuple have
are split into pairs where the members of the tuple have
meanings:
-- the stored candidate on the most common value of the measured entity
-- counter
-- total number of evaluations of the value */
*/
void
__gcov_merge_single (gcov_type *counters, unsigned n_counters)
{
unsigned i, n_measures;
gcov_type value, counter, all;
gcc_assert (!(n_counters % GCOV_SINGLE_VALUE_COUNTERS));
gcc_assert (!(n_counters % 3));
n_measures = n_counters / 3;
for (i = 0; i < n_measures; i++, counters += 3)
{
value = gcov_get_counter_target ();
counter = gcov_get_counter ();
all = gcov_get_counter ();
if (counters[0] == value)
counters[1] += counter;
else if (counter > counters[1])
{
counters[0] = value;
counters[1] = counter - counters[1];
}
else
counters[1] -= counter;
counters[2] += all;
}
for (unsigned i = 0; i < (n_counters / GCOV_SINGLE_VALUE_COUNTERS); i++)
merge_single_value_set (counters + (i * GCOV_SINGLE_VALUE_COUNTERS));
}
#endif /* L_gcov_merge_single */

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@ -112,40 +112,37 @@ __gcov_pow2_profiler_atomic (gcov_type *counters, gcov_type value)
COUNTERS[1] is decremented. Otherwise COUNTERS[1] is set to one and
VALUE is stored to COUNTERS[0]. This algorithm guarantees that if this
function is called more than 50% of the time with one value, this value
will be in COUNTERS[0] in the end.
In any case, COUNTERS[2] is incremented. If USE_ATOMIC is set to 1,
COUNTERS[2] is updated with an atomic instruction. */
will be in COUNTERS[0] in the end. */
static inline void
__gcov_one_value_profiler_body (gcov_type *counters, gcov_type value,
int use_atomic)
{
if (value == counters[0])
counters[1]++;
else if (counters[1] == 0)
if (value == counters[1])
counters[2]++;
else if (counters[2] == 0)
{
counters[1] = 1;
counters[0] = value;
counters[2] = 1;
counters[1] = value;
}
else
counters[1]--;
counters[2]--;
if (use_atomic)
__atomic_fetch_add (&counters[2], 1, __ATOMIC_RELAXED);
__atomic_fetch_add (&counters[0], 1, __ATOMIC_RELAXED);
else
counters[2]++;
counters[0]++;
}
#ifdef L_gcov_one_value_profiler
#ifdef L_gcov_one_value_profiler_v2
void
__gcov_one_value_profiler (gcov_type *counters, gcov_type value)
__gcov_one_value_profiler_v2 (gcov_type *counters, gcov_type value)
{
__gcov_one_value_profiler_body (counters, value, 0);
}
#endif
#if defined(L_gcov_one_value_profiler_atomic) && GCOV_SUPPORTS_ATOMIC
#if defined(L_gcov_one_value_profiler_v2_atomic) && GCOV_SUPPORTS_ATOMIC
/* Update one value profilers (COUNTERS) for a given VALUE.
@ -157,13 +154,13 @@ __gcov_one_value_profiler (gcov_type *counters, gcov_type value)
https://gcc.gnu.org/ml/gcc-patches/2016-08/msg00024.html. */
void
__gcov_one_value_profiler_atomic (gcov_type *counters, gcov_type value)
__gcov_one_value_profiler_v2_atomic (gcov_type *counters, gcov_type value)
{
__gcov_one_value_profiler_body (counters, value, 1);
}
#endif
#ifdef L_gcov_indirect_call_profiler_v3
#ifdef L_gcov_indirect_call_profiler_v4
/* These two variables are used to actually track caller and callee. Keep
them in TLS memory so races are not common (they are written to often).
@ -185,7 +182,7 @@ struct indirect_call_tuple __gcov_indirect_call;
/* Tries to determine the most common value among its inputs. */
void
__gcov_indirect_call_profiler_v3 (gcov_type value, void* cur_func)
__gcov_indirect_call_profiler_v4 (gcov_type value, void* cur_func)
{
/* If the C++ virtual tables contain function descriptors then one
function may have multiple descriptors and we need to dereference

View File

@ -271,9 +271,9 @@ extern void __gcov_interval_profiler_atomic (gcov_type *, gcov_type, int,
unsigned);
extern void __gcov_pow2_profiler (gcov_type *, gcov_type);
extern void __gcov_pow2_profiler_atomic (gcov_type *, gcov_type);
extern void __gcov_one_value_profiler (gcov_type *, gcov_type);
extern void __gcov_one_value_profiler_atomic (gcov_type *, gcov_type);
extern void __gcov_indirect_call_profiler_v3 (gcov_type, void *);
extern void __gcov_one_value_profiler_v2 (gcov_type *, gcov_type);
extern void __gcov_one_value_profiler_v2_atomic (gcov_type *, gcov_type);
extern void __gcov_indirect_call_profiler_v4 (gcov_type, void *);
extern void __gcov_time_profiler (gcov_type *);
extern void __gcov_time_profiler_atomic (gcov_type *);
extern void __gcov_average_profiler (gcov_type *, gcov_type);
@ -324,6 +324,29 @@ gcov_get_counter (void)
#endif
}
/* Similar function as gcov_get_counter(), but do not scale
when read value is equal to IGNORE_SCALING. */
static inline gcov_type
gcov_get_counter_ignore_scaling (gcov_type ignore_scaling)
{
#ifndef IN_GCOV_TOOL
/* This version is for reading count values in libgcov runtime:
we read from gcda files. */
return gcov_read_counter ();
#else
/* This version is for gcov-tool. We read the value from memory and
multiply it by the merge weight. */
gcov_type v = gcov_read_counter_mem ();
if (v != ignore_scaling)
v *= gcov_get_merge_weight ();
return v;
#endif
}
/* Similar function as gcov_get_counter(), but handles target address
counters. */