On 9/25/19 5:45 AM, luoxhu wrote:
> Hi,
>
> Sorry for replying so late due to cauldron conference and other LTO issues
> I was working on.
Hello.
That's fine, we still have plenty of time for patch review.
Not fixed issues which I reported in v3 (and still valid in v4):
- please come up with indirect_target_info::indirect_target_info and use it
- do you need to stream out indirect_call_targets when common_target_id == 0?
Then I'm suggesting to use vec::is_empty (please see my patch).
I see following failures for the tests provided:
FAIL: gcc.dg/tree-prof/crossmodule-indir-call-topn-1.c compilation,
-fprofile-generate -D_PROFILE_GENERATE
FAIL: gcc.dg/tree-prof/crossmodule-indir-call-topn-2.c compilation,
-fprofile-generate -D_PROFILE_GENERATE
FAIL: gcc.dg/tree-prof/indir-call-prof-topn.c compilation, -fprofile-generate
-D_PROFILE_GENERATE
Next comments follow directly in the email body:
>
> v4 Changes:
> 1. Rebase to trunk.
> 2. Remove num_of_ics and use vector's length to avoid redundancy.
> 3. Update the code in ipa-profile.c to improve review feasibility.
> 4. Add function has_indirect_call_p and has_multiple_indirect_call_p.
> 5. For parameter control, I will leave it to next patch as it is a
> relative independent function. Currently, maximum number of
> promotions is GCOV_TOPN_VALUES as only 4 profiling value limited
> from profile-generate, therefore minimum probability is adjusted to
> 25% in value-prof.c, it was 75% also by hard code for single
> indirect target. No control to minimal number of edge
> executions yet. What's more, this patch is a bit large now.
>
> This patch aims to fix PR69678 caused by PGO indirect call profiling
> performance issues.
> The bug that profiling data is never working was fixed by Martin's pull
> back of topN patches, performance got GEOMEAN ~1% improvement(+24% for
> 511.povray_r specifically).
> Still, currently the default profile only generates SINGLE indirect target
> that called more than 75%. This patch leverages MULTIPLE indirect
> targets use in LTO-WPA and LTO-LTRANS stage, as a result, function
> specialization, profiling, partial devirtualization, inlining and
> cloning could be done successfully based on it.
> Performance can get improved from 0.70 sec to 0.38 sec on simple tests.
> Details are:
> 1. PGO with topn is enabled by default now, but only one indirect
> target edge will be generated in ipa-profile pass, so add variables to
> enable
> multiple speculative edges through passes, speculative_id will record the
> direct edge index bind to the indirect edge, indirect_call_targets length
> records how many direct edges owned by the indirect edge, postpone gimple_ic
> to ipa-profile like default as inline pass will decide whether it is benefit
> to transform indirect call.
> 2. Use speculative_id to track and search the reference node matched
> with the direct edge's callee for multiple targets. Actually, it is the
> caller's responsibility to handle the direct edges mapped to same indirect
> edge. speculative_call_info will return one of the direct edge specified,
> this will leverage current IPA edge process framework mostly.
> 3. Enable LTO WPA/LTRANS stage multiple indirect call targets analysis for
> profile full support in ipa passes and cgraph_edge functions.
> speculative_id
> can be set by make_speculative id when multiple targets are binded to
> one indirect edge, and cloned if new edge is cloned. speculative_id
> is streamed out and stream int by lto like lto_stmt_uid.
> 4. Add 1 in module testcase and 2 cross module testcases.
> 5. Bootstrap and regression test passed on Power8-LE. No function
> and performance regression for SPEC2017.
>
> gcc/ChangeLog
>
> 2019-09-25 Xiong Hu Luo <[email protected]>
>
> PR ipa/69678
> * cgraph.c (symbol_table::create_edge): Init speculative_id.
> (cgraph_edge::make_speculative): Add param for setting speculative_id.
> (cgraph_edge::speculative_call_info): Find reference by
> speculative_id for multiple indirect targets.
> (cgraph_edge::resolve_speculation): Decrease the speculations
> for indirect edge, drop it's speculative if not direct target
> left.
> (cgraph_edge::redirect_call_stmt_to_callee): Likewise.
> (cgraph_node::verify_node): Don't report error if speculative
> edge not include statement.
> (cgraph_edge::has_multiple_indirect_call_p): New function.
> (cgraph_edge::has_indirect_call_p): New function.
> * cgraph.h (struct indirect_target_info): New struct.
> (indirect_call_targets): New vector variable.
> (make_speculative): Add param for setting speculative_id.
> (cgraph_edge::has_multiple_indirect_call_p): New declare.
> (cgraph_edge::has_indirect_call_p): New declare.
> (speculative_id): New variable.
> * cgraphclones.c (cgraph_node::create_clone): Clone speculative_id.
> * ipa-inline.c (inline_small_functions): Fix iterator update.
> * ipa-profile.c (ipa_profile_generate_summary): Add indirect
> multiple targets logic.
> (ipa_profile): Likewise.
> * ipa-ref.h (speculative_id): New variable.
> * ipa.c (process_references): Fix typo.
> * lto-cgraph.c (lto_output_edge): Add indirect multiple targets
> logic. Stream out speculative_id.
> (input_edge): Likewise.
> * predict.c (dump_prediction): Remove edges count assert to be
> precise.
> * symtab.c (symtab_node::create_reference): Init speculative_id.
> (symtab_node::clone_references): Clone speculative_id.
> (symtab_node::clone_referring): Clone speculative_id.
> (symtab_node::clone_reference): Clone speculative_id.
> (symtab_node::clear_stmts_in_references): Clear speculative_id.
> * tree-inline.c (copy_bb): Duplicate all the speculative edges
> if indirect call contains multiple speculative targets.
> * tree-profile.c (gimple_gen_ic_profiler): Use the new variable
> __gcov_indirect_call.counters and __gcov_indirect_call.callee.
> (gimple_gen_ic_func_profiler): Likewise.
> (pass_ipa_tree_profile::gate): Fix comment typos.
> * value-prof.c (gimple_ic_transform): Handle topn case.
> Fix comment typos.
>
> gcc/testsuite/ChangeLog
>
> 2019-09-25 Xiong Hu Luo <[email protected]>
>
> PR ipa/69678
> * gcc.dg/tree-prof/indir-call-prof-topn.c: New testcase.
> * gcc.dg/tree-prof/crossmodule-indir-call-topn-1.c: New testcase.
> * gcc.dg/tree-prof/crossmodule-indir-call-topn-1a.c: New testcase.
> * gcc.dg/tree-prof/crossmodule-indir-call-topn-2.c: New testcase.
> ---
> gcc/cgraph.c | 90 ++++++++++++++++-
> gcc/cgraph.h | 29 +++++-
> gcc/cgraphclones.c | 1 +
> gcc/ipa-inline.c | 15 +--
> gcc/ipa-profile.c | 96 ++++++++++++++-----
> gcc/ipa-ref.h | 1 +
> gcc/ipa.c | 2 +-
> gcc/lto-cgraph.c | 57 +++++++++--
> gcc/predict.c | 1 -
> gcc/symtab.c | 5 +
> .../tree-prof/crossmodule-indir-call-topn-1.c | 35 +++++++
> .../crossmodule-indir-call-topn-1a.c | 22 +++++
> .../tree-prof/crossmodule-indir-call-topn-2.c | 42 ++++++++
> .../gcc.dg/tree-prof/indir-call-prof-topn.c | 38 ++++++++
> gcc/tree-inline.c | 19 ++++
> gcc/tree-profile.c | 12 +--
> gcc/value-prof.c | 86 +++++++++--------
> 17 files changed, 452 insertions(+), 99 deletions(-)
> create mode 100644
> gcc/testsuite/gcc.dg/tree-prof/crossmodule-indir-call-topn-1.c
> create mode 100644
> gcc/testsuite/gcc.dg/tree-prof/crossmodule-indir-call-topn-1a.c
> create mode 100644
> gcc/testsuite/gcc.dg/tree-prof/crossmodule-indir-call-topn-2.c
> create mode 100644 gcc/testsuite/gcc.dg/tree-prof/indir-call-prof-topn.c
>
> diff --git a/gcc/cgraph.c b/gcc/cgraph.c
> index 843891e9e56..9a28aca435f 100644
> --- a/gcc/cgraph.c
> +++ b/gcc/cgraph.c
> @@ -860,6 +860,7 @@ symbol_table::create_edge (cgraph_node *caller,
> cgraph_node *callee,
> edge->prev_callee = NULL;
> edge->next_callee = NULL;
> edge->lto_stmt_uid = 0;
> + edge->speculative_id = 0;
>
> edge->count = count;
>
> @@ -1051,7 +1052,8 @@ cgraph_edge::remove (void)
> Return direct edge created. */
>
> cgraph_edge *
> -cgraph_edge::make_speculative (cgraph_node *n2, profile_count direct_count)
> +cgraph_edge::make_speculative (cgraph_node *n2, profile_count direct_count,
> + unsigned int speculative_id)
> {
> cgraph_node *n = caller;
> ipa_ref *ref = NULL;
> @@ -1069,11 +1071,13 @@ cgraph_edge::make_speculative (cgraph_node *n2,
> profile_count direct_count)
> else
> e2->can_throw_external = can_throw_external;
> e2->lto_stmt_uid = lto_stmt_uid;
> + e2->speculative_id = speculative_id;
> e2->in_polymorphic_cdtor = in_polymorphic_cdtor;
> count -= e2->count;
> symtab->call_edge_duplication_hooks (this, e2);
> ref = n->create_reference (n2, IPA_REF_ADDR, call_stmt);
> ref->lto_stmt_uid = lto_stmt_uid;
> + ref->speculative_id = speculative_id;
> ref->speculative = speculative;
> n2->mark_address_taken ();
> return e2;
> @@ -1087,6 +1091,38 @@ cgraph_edge::make_speculative (cgraph_node *n2,
> profile_count direct_count)
> call) and if one of them exists, all of them must exist.
>
> Given speculative call edge, return all three components.
> +
> + For some indirect edge, it may maps to multiple direct edges, i.e. 1:N.
> + check the speculative_id to return all the three components for specified
> + direct edge or indirect edge.
> + If input is indirect, caller of this function will get the direct edge
> one by
> + one, get_edge will just return one of the direct edge mapped to the
> indirect
> + edge, the returned direct edge will be resolved or redirected by the
> caller,
> + then number of indirect calls (speculations) is deceased in each access.
> + If input is direct, this function will get the indirect edge and reference
> + with matched speculative_id, the returned edge will also be resolved or
> + redirected, decrease the speculations accordingly.
> + Speculations of indirect edge will be dropped only if all direct edges
> + be handled.
> +
> + e.g. for indirect edge E statement "call call_dest":
> +
> + Redirect N3 after redirected N2:
> +
> + if (call_dest == N2)
> + n2 ();
> + else if (call_dest == N3)
> + n3 ();
> + else
> + call call_dest
> +
> + Resolve N3 and only redirect N2:
> +
> + if (call_dest == N2)
> + n2 ();
> + else
> + call call_dest
> +
> */
>
> void
> @@ -1126,7 +1162,7 @@ cgraph_edge::speculative_call_info (cgraph_edge
> *&direct,
>
> reference = NULL;
> for (i = 0; e->caller->iterate_reference (i, ref); i++)
> - if (ref->speculative
> + if (ref->speculative && ref->speculative_id == e->speculative_id
> && ((ref->stmt && ref->stmt == e->call_stmt)
> || (!ref->stmt && ref->lto_stmt_uid == e->lto_stmt_uid)))
> {
> @@ -1187,7 +1223,21 @@ cgraph_edge::resolve_speculation (tree callee_decl)
> in the functions inlined through it. */
> }
> edge->count += e2->count;
> - edge->speculative = false;
> + /* edge is indirect, e2 is direct. If edge contains multiple speculations,
> + remove one of speculations for this indirect edge, then if edge still
> + contains direct target, keep the speculation, next direct target
> + will continue use it. Give up speculation completely if no direct
> + target is left for this indirect edge. */
> + if (edge->has_indirect_call_p ())
> + {
> + /* As the direct targets are sorted by decrease, delete the first
> target
> + when it is resolved. */
> + edge->indirect_info->indirect_call_targets->ordered_remove (0);
> + if (!edge->indirect_info->indirect_call_targets->length ())
> + edge->speculative = false;
> + }
> + else
> + edge->speculative = false;
> e2->speculative = false;
> ref->remove_reference ();
> if (e2->indirect_unknown_callee || e2->inline_failed)
> @@ -1321,7 +1371,21 @@ cgraph_edge::redirect_call_stmt_to_callee (void)
> e->caller->set_call_stmt_including_clones (e->call_stmt, new_stmt,
> false);
> e->count = gimple_bb (e->call_stmt)->count;
> - e2->speculative = false;
> + /* edge is direct, e2 is indirect here. If e2 contains multiple
> + speculations, remove one of speculations for this indirect edge,
> + then if e2 still contains direct target, keep the speculation,
> + next direct target will continue use it. Give up speculation
> + completely if no direct target is left for this indirect e2. */
> + if (e2->has_indirect_call_p ())
> + {
> + /* As the direct targets are sorted by decrease, delete the first
> + target when it is redirected. */
> + e2->indirect_info->indirect_call_targets->ordered_remove (0);
> + if (!e2->indirect_info->indirect_call_targets->length ())
> + e2->speculative = false;
> + }
> + else
> + e2->speculative = false;
> e2->count = gimple_bb (e2->call_stmt)->count;
> ref->speculative = false;
> ref->stmt = NULL;
> @@ -3445,7 +3509,7 @@ cgraph_node::verify_node (void)
>
> for (e = callees; e; e = e->next_callee)
> {
> - if (!e->aux)
> + if (!e->aux && !e->speculative)
> {
> error ("edge %s->%s has no corresponding call_stmt",
> identifier_to_locale (e->caller->name ()),
> @@ -3872,6 +3936,22 @@ cgraph_edge::possibly_call_in_translation_unit_p (void)
> return node->get_availability () >= AVAIL_AVAILABLE;
> }
>
> +/* Return true if this edge has multiple indirect call targets. */
> +bool
> +cgraph_edge::has_multiple_indirect_call_p (void)
> +{
> + return indirect_info && indirect_info->indirect_call_targets
> + && indirect_info->indirect_call_targets->length () > 1;
> +}
For multiline && expression, we typically wrap the whole condition
in '(' and ')'.
> +
> +/* Return true if this edge has at least one indirect call target. */
> +bool
> +cgraph_edge::has_indirect_call_p (void)
> +{
> + return indirect_info && indirect_info->indirect_call_targets
> + && indirect_info->indirect_call_targets->length ();
> +}
Likewise here.
> +
> /* A stashed copy of "symtab" for use by selftest::symbol_table_test.
> This needs to be a global so that it can be a GC root, and thus
> prevent the stashed copy from being garbage-collected if the GC runs
> diff --git a/gcc/cgraph.h b/gcc/cgraph.h
> index 4c54210123a..33c8454c4e0 100644
> --- a/gcc/cgraph.h
> +++ b/gcc/cgraph.h
> @@ -1636,6 +1636,16 @@ private:
> void make_speculative (tree otr_type = NULL);
> };
>
> +/* Structure containing indirect target information from profile. */
> +
> +struct GTY (()) indirect_target_info
> +{
> + /* Profile_id of common target obtained from profile. */
> + unsigned int common_target_id;
> + /* Probability that call will land in function with COMMON_TARGET_ID. */
> + int common_target_probability;
> +};
> +
> /* Structure containing additional information about an indirect call. */
>
> class GTY(()) cgraph_indirect_call_info
> @@ -1654,10 +1664,9 @@ public:
> int param_index;
> /* ECF flags determined from the caller. */
> int ecf_flags;
> - /* Profile_id of common target obtrained from profile. */
> - int common_target_id;
> - /* Probability that call will land in function with COMMON_TARGET_ID. */
> - int common_target_probability;
> +
> + /* An indirect call may contain one or multiple call targets. */
> + vec<indirect_target_info, va_gc> *indirect_call_targets;
>
> /* Set when the call is a virtual call with the parameter being the
> associated object pointer rather than a simple direct call. */
> @@ -1714,7 +1723,8 @@ public:
> /* Turn edge into speculative call calling N2. Update
> the profile so the direct call is taken COUNT times
> with FREQUENCY. */
> - cgraph_edge *make_speculative (cgraph_node *n2, profile_count
> direct_count);
> + cgraph_edge *make_speculative (cgraph_node *n2, profile_count direct_count,
> + unsigned int speculative_id = 0);
>
> /* Given speculative call edge, return all three components. */
> void speculative_call_info (cgraph_edge *&direct, cgraph_edge *&indirect,
> @@ -1773,6 +1783,12 @@ public:
> be internal to the current translation unit. */
> bool possibly_call_in_translation_unit_p (void);
>
> + /* Return true if this edge has multiple indirect call targets. */
> + bool has_multiple_indirect_call_p (void);
> +
> + /* Return true if this edge has at least one indirect call target. */
> + bool has_indirect_call_p (void);
> +
> /* Expected number of executions: calculated in profile.c. */
> profile_count count;
> cgraph_node *caller;
> @@ -1792,6 +1808,9 @@ public:
> /* The stmt_uid of call_stmt. This is used by LTO to recover the call_stmt
> when the function is serialized in. */
> unsigned int lto_stmt_uid;
> + /* speculative id is used by multiple indirect targets when the function is
> + speculated. */
> + unsigned int speculative_id;
> /* Whether this edge was made direct by indirect inlining. */
> unsigned int indirect_inlining_edge : 1;
> /* Whether this edge describes an indirect call with an undetermined
> diff --git a/gcc/cgraphclones.c b/gcc/cgraphclones.c
> index fa753697c78..5dbd8d90b77 100644
> --- a/gcc/cgraphclones.c
> +++ b/gcc/cgraphclones.c
> @@ -128,6 +128,7 @@ cgraph_edge::clone (cgraph_node *n, gcall *call_stmt,
> unsigned stmt_uid,
> new_edge->inline_failed = inline_failed;
> new_edge->indirect_inlining_edge = indirect_inlining_edge;
> new_edge->lto_stmt_uid = stmt_uid;
> + new_edge->speculative_id = speculative_id;
> /* Clone flags that depend on call_stmt availability manually. */
> new_edge->can_throw_external = can_throw_external;
> new_edge->call_stmt_cannot_inline_p = call_stmt_cannot_inline_p;
> diff --git a/gcc/ipa-inline.c b/gcc/ipa-inline.c
> index b62d280eb25..6136214f9ac 100644
> --- a/gcc/ipa-inline.c
> +++ b/gcc/ipa-inline.c
> @@ -1881,12 +1881,15 @@ inline_small_functions (void)
> }
> if (has_speculative)
> for (edge = node->callees; edge; edge = next)
> - if (edge->speculative && !speculation_useful_p (edge,
> - edge->aux != NULL))
> - {
> - edge->resolve_speculation ();
> - update = true;
> - }
> + {
> + next = edge->next_callee;
> + if (edge->speculative
> + && !speculation_useful_p (edge, edge->aux != NULL))
> + {
> + edge->resolve_speculation ();
> + update = true;
> + }
> + }
> if (update)
> {
> struct cgraph_node *where = node->global.inlined_to
> diff --git a/gcc/ipa-profile.c b/gcc/ipa-profile.c
> index 970dba39c80..342e8ea05d1 100644
> --- a/gcc/ipa-profile.c
> +++ b/gcc/ipa-profile.c
> @@ -192,23 +192,35 @@ ipa_profile_generate_summary (void)
> if (h)
> {
> gcov_type val, count, all;
> - if (get_nth_most_common_value (NULL, "indirect call", h,
> - &val, &count, &all))
> + struct cgraph_edge *e = node->get_edge (stmt);
> + if (e && !e->indirect_unknown_callee)
> + continue;
> +
> + struct indirect_target_info item;
> + for (unsigned j = 0; j < GCOV_TOPN_VALUES; j++)
> {
> - struct cgraph_edge * e = node->get_edge (stmt);
> - if (e && !e->indirect_unknown_callee)
> + if (!get_nth_most_common_value (NULL, "indirect call",
> + h, &val, &count, &all,
> + j))
> + continue;
> +
> + if (val == 0)
> continue;
>
> - e->indirect_info->common_target_id = val;
> - e->indirect_info->common_target_probability
> + item.common_target_id = val;
> + item.common_target_probability
> = GCOV_COMPUTE_SCALE (count, all);
There's one of the places where you can use the constructor.
> - if (e->indirect_info->common_target_probability >
> REG_BR_PROB_BASE)
> + if (item.common_target_probability > REG_BR_PROB_BASE)
> {
> if (dump_file)
> - fprintf (dump_file, "Probability capped to
> 1\n");
> - e->indirect_info->common_target_probability =
> REG_BR_PROB_BASE;
> + fprintf (dump_file,
> + "Probability capped to 1\n");
> + item.common_target_probability = REG_BR_PROB_BASE;
> }
> + vec_safe_push (
> + e->indirect_info->indirect_call_targets, item);
> }
> +
> gimple_remove_histogram_value (DECL_STRUCT_FUNCTION
> (node->decl),
> stmt, h);
> }
> @@ -492,6 +504,7 @@ ipa_profile (void)
> int nindirect = 0, ncommon = 0, nunknown = 0, nuseless = 0, nconverted = 0;
> int nmismatch = 0, nimpossible = 0;
> bool node_map_initialized = false;
> + gcov_type threshold;
>
> if (dump_file)
> dump_histogram (dump_file, histogram);
> @@ -500,14 +513,12 @@ ipa_profile (void)
> overall_time += histogram[i]->count * histogram[i]->time;
> overall_size += histogram[i]->size;
> }
> + threshold = 0;
> if (overall_time)
> {
> - gcov_type threshold;
> -
> gcc_assert (overall_size);
>
> cutoff = (overall_time * PARAM_VALUE (HOT_BB_COUNT_WS_PERMILLE) + 500)
> / 1000;
> - threshold = 0;
> for (i = 0; cumulated < cutoff; i++)
> {
> cumulated += histogram[i]->count * histogram[i]->time;
> @@ -543,7 +554,7 @@ ipa_profile (void)
> histogram.release ();
> histogram_pool.release ();
>
> - /* Produce speculative calls: we saved common traget from porfiling into
> + /* Produce speculative calls: we saved common target from profiling into
> e->common_target_id. Now, at link time, we can look up corresponding
> function node and produce speculative call. */
>
> @@ -558,13 +569,37 @@ ipa_profile (void)
> {
> if (n->count.initialized_p ())
> nindirect++;
> - if (e->indirect_info->common_target_id)
> + if (e->has_indirect_call_p ())
> {
> if (!node_map_initialized)
> - init_node_map (false);
> + init_node_map (false);
> node_map_initialized = true;
> ncommon++;
> - n2 = find_func_by_profile_id (e->indirect_info->common_target_id);
> +
> + if (in_lto_p)
> + {
> + if (dump_file)
> + {
> + fprintf (dump_file,
> + "Updating hotness threshold in LTO mode.\n");
> + fprintf (dump_file, "Updated min count: %" PRId64 "\n",
> + (int64_t) threshold);
> + }
> + set_hot_bb_threshold (threshold
> + / e->indirect_info->indirect_call_targets->length ());
> + }
> +
> + unsigned speculative_id = 0;
> + struct indirect_target_info *item;
> + /* The code below is not formatted yet for review convenience.
> + Move to a seprate small function is not easy as too many local
> + variables used in it. Need format and remove this comments
> + once got approved. */
> + FOR_EACH_VEC_SAFE_ELT (e->indirect_info->indirect_call_targets, i,
> + item)
> + {
> + bool speculative_found = false;
> + n2 = find_func_by_profile_id (item->common_target_id);
> if (n2)
> {
> if (dump_file)
> @@ -573,11 +608,10 @@ ipa_profile (void)
> " other module %s => %s, prob %3.2f\n",
> n->dump_name (),
> n2->dump_name (),
> - e->indirect_info->common_target_probability
> - / (float)REG_BR_PROB_BASE);
> + item->common_target_probability
> + / (float) REG_BR_PROB_BASE);
> }
> - if (e->indirect_info->common_target_probability
> - < REG_BR_PROB_BASE / 2)
> + if (item->common_target_probability < REG_BR_PROB_BASE / 2)
> {
> nuseless++;
> if (dump_file)
> @@ -613,7 +647,7 @@ ipa_profile (void)
> if (dump_file)
> fprintf (dump_file,
> "Not speculating: "
> - "parameter count mistmatch\n");
> + "parameter count mismatch\n");
> }
> else if (e->indirect_info->polymorphic
> && !opt_for_fn (n->decl, flag_devirtualize)
> @@ -640,20 +674,30 @@ ipa_profile (void)
> n2 = alias;
> }
> nconverted++;
> - e->make_speculative
> - (n2,
> - e->count.apply_probability
> -
> (e->indirect_info->common_target_probability));
> + e->make_speculative (n2,
> + e->count.apply_probability (
> + item->common_target_probability),
> + speculative_id);
> update = true;
> + speculative_id++;
> + speculative_found = true;
> }
> }
> else
> {
> if (dump_file)
> fprintf (dump_file, "Function with profile-id %i not
> found.\n",
> - e->indirect_info->common_target_id);
> + item->common_target_id);
> nunknown++;
> }
> + if (!speculative_found)
> + {
> + /* Remove item from indirect_call_targets if no
> + speculative edge generated, rollback the iteration. */
> + e->indirect_info->indirect_call_targets->ordered_remove (i);
> + i--;
> + }
> + }
> }
> }
> if (update)
> diff --git a/gcc/ipa-ref.h b/gcc/ipa-ref.h
> index 0d8e509c932..3e6562ec9d1 100644
> --- a/gcc/ipa-ref.h
> +++ b/gcc/ipa-ref.h
> @@ -59,6 +59,7 @@ public:
> symtab_node *referred;
> gimple *stmt;
> unsigned int lto_stmt_uid;
> + unsigned int speculative_id;
> unsigned int referred_index;
> ENUM_BITFIELD (ipa_ref_use) use:3;
> unsigned int speculative:1;
> diff --git a/gcc/ipa.c b/gcc/ipa.c
> index 6b84e1f9bda..a10b0603f14 100644
> --- a/gcc/ipa.c
> +++ b/gcc/ipa.c
> @@ -166,7 +166,7 @@ process_references (symtab_node *snode,
> devirtualization happens. After inlining still keep their declarations
> around, so we can devirtualize to a direct call.
>
> - Also try to make trivial devirutalization when no or only one target is
> + Also try to make trivial devirtualization when no or only one target is
> possible. */
>
> static void
> diff --git a/gcc/lto-cgraph.c b/gcc/lto-cgraph.c
> index bc0f0107333..61380dcc7b8 100644
> --- a/gcc/lto-cgraph.c
> +++ b/gcc/lto-cgraph.c
> @@ -238,6 +238,7 @@ lto_output_edge (struct lto_simple_output_block *ob,
> struct cgraph_edge *edge,
> unsigned int uid;
> intptr_t ref;
> struct bitpack_d bp;
> + unsigned len;
>
> if (edge->indirect_unknown_callee)
> streamer_write_enum (ob->main_stream, LTO_symtab_tags,
> LTO_symtab_last_tag,
> @@ -265,6 +266,7 @@ lto_output_edge (struct lto_simple_output_block *ob,
> struct cgraph_edge *edge,
> bp_pack_enum (&bp, cgraph_inline_failed_t,
> CIF_N_REASONS, edge->inline_failed);
> bp_pack_var_len_unsigned (&bp, uid);
> + bp_pack_var_len_unsigned (&bp, edge->speculative_id);
> bp_pack_value (&bp, edge->indirect_inlining_edge, 1);
> bp_pack_value (&bp, edge->speculative, 1);
> bp_pack_value (&bp, edge->call_stmt_cannot_inline_p, 1);
> @@ -291,11 +293,27 @@ lto_output_edge (struct lto_simple_output_block *ob,
> struct cgraph_edge *edge,
> streamer_write_bitpack (&bp);
> if (edge->indirect_unknown_callee)
> {
> - streamer_write_hwi_stream (ob->main_stream,
> - edge->indirect_info->common_target_id);
> - if (edge->indirect_info->common_target_id)
> - streamer_write_hwi_stream
> - (ob->main_stream, edge->indirect_info->common_target_probability);
> + struct indirect_target_info *item;
> + unsigned int i;
> + len = edge->has_indirect_call_p ()
> + ? edge->indirect_info->indirect_call_targets->length ()
> + : 0;
> + gcc_assert (len <= GCOV_TOPN_VALUES);
> +
> + streamer_write_hwi_stream (ob->main_stream, len);
> +
> + if (len)
> + {
> + FOR_EACH_VEC_SAFE_ELT (edge->indirect_info->indirect_call_targets, i,
> + item)
> + {
> + streamer_write_hwi_stream (ob->main_stream,
> + item->common_target_id);
> + if (item->common_target_id)
> + streamer_write_hwi_stream (ob->main_stream,
> + item->common_target_probability);
> + }
> + }
> }
> }
>
> @@ -688,6 +706,7 @@ lto_output_ref (struct lto_simple_output_block *ob,
> struct ipa_ref *ref,
> if (ref->stmt)
> uid = gimple_uid (ref->stmt) + 1;
> streamer_write_hwi_stream (ob->main_stream, uid);
> + streamer_write_hwi_stream (ob->main_stream, ref->speculative_id);
> }
> }
>
> @@ -1419,7 +1438,10 @@ input_ref (class lto_input_block *ib,
> ref = referring_node->create_reference (node, use);
> ref->speculative = speculative;
> if (is_a <cgraph_node *> (referring_node))
> - ref->lto_stmt_uid = streamer_read_hwi (ib);
> + {
> + ref->lto_stmt_uid = streamer_read_hwi (ib);
> + ref->speculative_id = streamer_read_hwi (ib);
> + }
> }
>
> /* Read an edge from IB. NODES points to a vector of previously read nodes
> for
> @@ -1433,11 +1455,12 @@ input_edge (class lto_input_block *ib,
> vec<symtab_node *> nodes,
> {
> struct cgraph_node *caller, *callee;
> struct cgraph_edge *edge;
> - unsigned int stmt_id;
> + unsigned int stmt_id, speculative_id;
> profile_count count;
> cgraph_inline_failed_t inline_failed;
> struct bitpack_d bp;
> int ecf_flags = 0;
> + unsigned i, len;
>
> caller = dyn_cast<cgraph_node *> (nodes[streamer_read_hwi (ib)]);
> if (caller == NULL || caller->decl == NULL_TREE)
> @@ -1457,6 +1480,7 @@ input_edge (class lto_input_block *ib, vec<symtab_node
> *> nodes,
> bp = streamer_read_bitpack (ib);
> inline_failed = bp_unpack_enum (&bp, cgraph_inline_failed_t,
> CIF_N_REASONS);
> stmt_id = bp_unpack_var_len_unsigned (&bp);
> + speculative_id = bp_unpack_var_len_unsigned (&bp);
>
> if (indirect)
> edge = caller->create_indirect_edge (NULL, 0, count);
> @@ -1466,6 +1490,7 @@ input_edge (class lto_input_block *ib, vec<symtab_node
> *> nodes,
> edge->indirect_inlining_edge = bp_unpack_value (&bp, 1);
> edge->speculative = bp_unpack_value (&bp, 1);
> edge->lto_stmt_uid = stmt_id;
> + edge->speculative_id = speculative_id;
> edge->inline_failed = inline_failed;
> edge->call_stmt_cannot_inline_p = bp_unpack_value (&bp, 1);
> edge->can_throw_external = bp_unpack_value (&bp, 1);
> @@ -1485,9 +1510,21 @@ input_edge (class lto_input_block *ib, vec<symtab_node
> *> nodes,
> if (bp_unpack_value (&bp, 1))
> ecf_flags |= ECF_RETURNS_TWICE;
> edge->indirect_info->ecf_flags = ecf_flags;
> - edge->indirect_info->common_target_id = streamer_read_hwi (ib);
> - if (edge->indirect_info->common_target_id)
> - edge->indirect_info->common_target_probability = streamer_read_hwi
> (ib);
> +
> + len = streamer_read_hwi (ib);
> +
> + gcc_assert (len <= GCOV_TOPN_VALUES);
> +
> + if (len)
> + {
> + indirect_target_info item;
> + for (i = 0; i < len; i++)
> + {
> + item.common_target_id = streamer_read_hwi (ib);
> + item.common_target_probability = streamer_read_hwi (ib);
> + vec_safe_push (edge->indirect_info->indirect_call_targets, item);
> + }
> + }
> }
> }
>
> diff --git a/gcc/predict.c b/gcc/predict.c
> index 915f0806b11..3f56fa3a74a 100644
> --- a/gcc/predict.c
> +++ b/gcc/predict.c
> @@ -762,7 +762,6 @@ dump_prediction (FILE *file, enum br_predictor predictor,
> int probability,
> && bb->count.precise_p ()
> && reason == REASON_NONE)
> {
> - gcc_assert (e->count ().precise_p ());
> fprintf (file, ";;heuristics;%s;%" PRId64 ";%" PRId64 ";%.1f;\n",
> predictor_info[predictor].name,
> bb->count.to_gcov_type (), e->count ().to_gcov_type (),
> diff --git a/gcc/symtab.c b/gcc/symtab.c
> index ee9723c3453..d4c36fd3e5a 100644
> --- a/gcc/symtab.c
> +++ b/gcc/symtab.c
> @@ -603,6 +603,7 @@ symtab_node::create_reference (symtab_node *referred_node,
> ref->referred = referred_node;
> ref->stmt = stmt;
> ref->lto_stmt_uid = 0;
> + ref->speculative_id = 0;
> ref->use = use_type;
> ref->speculative = 0;
>
> @@ -660,6 +661,7 @@ symtab_node::clone_references (symtab_node *node)
> ref2 = create_reference (ref->referred, ref->use, ref->stmt);
> ref2->speculative = speculative;
> ref2->lto_stmt_uid = stmt_uid;
> + ref2->speculative_id = ref->speculative_id;
> }
> }
>
> @@ -678,6 +680,7 @@ symtab_node::clone_referring (symtab_node *node)
> ref2 = ref->referring->create_reference (this, ref->use, ref->stmt);
> ref2->speculative = speculative;
> ref2->lto_stmt_uid = stmt_uid;
> + ref2->speculative_id = ref->speculative_id;
> }
> }
>
> @@ -693,6 +696,7 @@ symtab_node::clone_reference (ipa_ref *ref, gimple *stmt)
> ref2 = create_reference (ref->referred, ref->use, stmt);
> ref2->speculative = speculative;
> ref2->lto_stmt_uid = stmt_uid;
> + ref2->speculative_id = ref->speculative_id;
> return ref2;
> }
>
> @@ -747,6 +751,7 @@ symtab_node::clear_stmts_in_references (void)
> {
> r->stmt = NULL;
> r->lto_stmt_uid = 0;
> + r->speculative_id = 0;
> }
> }
>
> diff --git a/gcc/testsuite/gcc.dg/tree-prof/crossmodule-indir-call-topn-1.c
> b/gcc/testsuite/gcc.dg/tree-prof/crossmodule-indir-call-topn-1.c
> new file mode 100644
> index 00000000000..e0a83c2e067
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/tree-prof/crossmodule-indir-call-topn-1.c
> @@ -0,0 +1,35 @@
> +/* { dg-require-effective-target lto } */
> +/* { dg-additional-sources "crossmodule-indir-call-topn-1a.c" } */
> +/* { dg-require-profiling "-fprofile-generate" } */
> +/* { dg-options "-O2 -flto -DDOJOB=1 -fdump-ipa-profile_estimate --param
> indir-call-topn-profile=1" } */
> +
> +#include <stdio.h>
> +
> +typedef int (*fptr) (int);
> +int
> +one (int a);
> +
> +int
> +two (int a);
> +
> +fptr table[] = {&one, &two};
> +
> +int
> +main()
> +{
> + int i, x;
> + fptr p = &one;
> +
> + x = one (3);
> +
> + for (i = 0; i < 350000000; i++)
> + {
> + x = (*p) (3);
> + p = table[x];
> + }
> + printf ("done:%d\n", x);
> +}
> +
> +/* { dg-final-use-not-autofdo { scan-wpa-ipa-dump "Indirect call -> direct
> call.* one transformation on insn" "profile_estimate" } } */
> +/* { dg-final-use-not-autofdo { scan-wpa-ipa-dump "Indirect call -> direct
> call.* two transformation on insn" "profile_estimate" } } */
> +
> diff --git a/gcc/testsuite/gcc.dg/tree-prof/crossmodule-indir-call-topn-1a.c
> b/gcc/testsuite/gcc.dg/tree-prof/crossmodule-indir-call-topn-1a.c
> new file mode 100644
> index 00000000000..a8c6e365fb9
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/tree-prof/crossmodule-indir-call-topn-1a.c
> @@ -0,0 +1,22 @@
> +/* It seems there is no way to avoid the other source of mulitple
> + source testcase from being compiled independently. Just avoid
> + error. */
> +#ifdef DOJOB
> +int
> +one (int a)
> +{
> + return 1;
> +}
> +
> +int
> +two (int a)
> +{
> + return 0;
> +}
> +#else
> +int
> +main()
> +{
> + return 0;
> +}
> +#endif
> diff --git a/gcc/testsuite/gcc.dg/tree-prof/crossmodule-indir-call-topn-2.c
> b/gcc/testsuite/gcc.dg/tree-prof/crossmodule-indir-call-topn-2.c
> new file mode 100644
> index 00000000000..aa3887fde83
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/tree-prof/crossmodule-indir-call-topn-2.c
> @@ -0,0 +1,42 @@
> +/* { dg-require-effective-target lto } */
> +/* { dg-additional-sources "crossmodule-indir-call-topn-1a.c" } */
> +/* { dg-require-profiling "-fprofile-generate" } */
> +/* { dg-options "-O2 -flto -DDOJOB=1 -fdump-ipa-profile_estimate --param
> indir-call-topn-profile=1" } */
> +
> +#include <stdio.h>
> +
> +typedef int (*fptr) (int);
> +int
> +one (int a);
> +
> +int
> +two (int a);
> +
> +fptr table[] = {&one, &two};
> +
> +int foo ()
> +{
> + int i, x;
> + fptr p = &one;
> +
> + x = one (3);
> +
> + for (i = 0; i < 350000000; i++)
> + {
> + x = (*p) (3);
> + p = table[x];
> + }
> + return x;
> +}
> +
> +int
> +main()
> +{
> + int x = foo ();
> + printf ("done:%d\n", x);
> +}
> +
> +/* { dg-final-use-not-autofdo { scan-wpa-ipa-dump "Indirect call -> direct
> call.* one transformation on insn" "profile_estimate" } } */
> +/* { dg-final-use-not-autofdo { scan-wpa-ipa-dump "Indirect call -> direct
> call.* two transformation on insn" "profile_estimate" } } */
> +
> +
> diff --git a/gcc/testsuite/gcc.dg/tree-prof/indir-call-prof-topn.c
> b/gcc/testsuite/gcc.dg/tree-prof/indir-call-prof-topn.c
> new file mode 100644
> index 00000000000..951bc7ddd19
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/tree-prof/indir-call-prof-topn.c
> @@ -0,0 +1,38 @@
> +/* { dg-require-profiling "-fprofile-generate" } */
> +/* { dg-options "-O2 -fdump-ipa-profile --param indir-call-topn-profile=1" }
> */
> +
> +#include <stdio.h>
> +
> +typedef int (*fptr) (int);
> +int
> +one (int a)
> +{
> + return 1;
> +}
> +
> +int
> +two (int a)
> +{
> + return 0;
> +}
> +
> +fptr table[] = {&one, &two};
> +
> +int
> +main()
> +{
> + int i, x;
> + fptr p = &one;
> +
> + one (3);
> +
> + for (i = 0; i < 350000000; i++)
> + {
> + x = (*p) (3);
> + p = table[x];
> + }
> + printf ("done:%d\n", x);
> +}
> +
> +/* { dg-final-use-not-autofdo { scan-ipa-dump "Indirect call -> direct
> call.* one transformation on insn" "profile" } } */
> +/* { dg-final-use-not-autofdo { scan-ipa-dump "Indirect call -> direct
> call.* two transformation on insn" "profile" } } */
> diff --git a/gcc/tree-inline.c b/gcc/tree-inline.c
> index b9c1a3b1456..fe3e172fbd1 100644
> --- a/gcc/tree-inline.c
> +++ b/gcc/tree-inline.c
> @@ -2167,6 +2167,25 @@ copy_bb (copy_body_data *id, basic_block bb,
>
> gcc_assert (!edge->indirect_unknown_callee);
> old_edge->speculative_call_info (direct, indirect,
> ref);
> + while (old_edge->next_callee
> + && old_edge->next_callee->speculative
> + && indirect->has_multiple_indirect_call_p ())
> + {
> + /* Some speculative calls may contain more than
> + one direct target, loop iterate it to clone all
> + related direct edges before cloning the related
> + indirect edge. */
> + id->dst_node->clone_reference (ref, stmt);
> +
> + edge = old_edge->next_callee;
> + edge = edge->clone (id->dst_node, call_stmt,
> + gimple_uid (stmt), num, den,
> + true);
> + old_edge = old_edge->next_callee;
> + gcc_assert (!edge->indirect_unknown_callee);
> + old_edge->speculative_call_info (direct, indirect,
> + ref);
> + }
>
> profile_count indir_cnt = indirect->count;
> indirect = indirect->clone (id->dst_node, call_stmt,
> diff --git a/gcc/tree-profile.c b/gcc/tree-profile.c
> index 4c1ead5781f..ef7748668f8 100644
> --- a/gcc/tree-profile.c
> +++ b/gcc/tree-profile.c
> @@ -74,8 +74,8 @@ static GTY(()) tree ic_tuple_callee_field;
> /* Do initialization work for the edge profiler. */
>
> /* Add code:
> - __thread gcov* __gcov_indirect_call_counters; // pointer to actual
> counter
> - __thread void* __gcov_indirect_call_callee; // actual callee address
> + __thread gcov* __gcov_indirect_call.counters; // pointer to actual
> counter
> + __thread void* __gcov_indirect_call.callee; // actual callee address
> __thread int __gcov_function_counter; // time profiler function counter
> */
> static void
> @@ -382,7 +382,7 @@ gimple_gen_ic_profiler (histogram_value value, unsigned
> tag)
> f_1 = foo;
> __gcov_indirect_call.counters = &__gcov4.main[0];
> PROF_9 = f_1;
> - __gcov_indirect_call_callee = PROF_9;
> + __gcov_indirect_call.callee = PROF_9;
> _4 = f_1 ();
> */
>
> @@ -445,11 +445,11 @@ gimple_gen_ic_func_profiler (void)
>
> /* Insert code:
>
> - if (__gcov_indirect_call_callee != NULL)
> + if (__gcov_indirect_call.callee != NULL)
> __gcov_indirect_call_profiler_v3 (profile_id, ¤t_function_decl);
>
> The function __gcov_indirect_call_profiler_v3 is responsible for
> - resetting __gcov_indirect_call_callee to NULL. */
> + resetting __gcov_indirect_call.callee to NULL. */
>
> gimple_stmt_iterator gsi = gsi_start_bb (cond_bb);
> void0 = build_int_cst (ptr_type_node, 0);
> @@ -891,7 +891,7 @@ pass_ipa_tree_profile::gate (function *)
> {
> /* When profile instrumentation, use or test coverage shall be performed.
> But for AutoFDO, this there is no instrumentation, thus this pass is
> - diabled. */
> + disabled. */
> return (!in_lto_p && !flag_auto_profile
> && (flag_branch_probabilities || flag_test_coverage
> || profile_arc_flag));
> diff --git a/gcc/value-prof.c b/gcc/value-prof.c
> index 55ea0973a03..0588df0fce9 100644
> --- a/gcc/value-prof.c
> +++ b/gcc/value-prof.c
> @@ -1406,11 +1406,10 @@ gimple_ic (gcall *icall_stmt, struct cgraph_node
> *direct_call,
> return dcall_stmt;
> }
>
> -/*
> - For every checked indirect/virtual call determine if most common pid of
> - function/class method has probability more than 50%. If yes modify code of
> - this call to:
> - */
> +/* There maybe multiple indirect targets in histogram. Check every
> + indirect/virtual call if callee function exists, if not exist, leave it to
> + LTO stage for later process. Modify code of this indirect call to an
> if-else
> + structure in ipa-profile finally. */
>
> static bool
> gimple_ic_transform (gimple_stmt_iterator *gsi)
> @@ -1434,48 +1433,57 @@ gimple_ic_transform (gimple_stmt_iterator *gsi)
> if (!histogram)
> return false;
The function is not correct, note that the function can now return true
when this transformation happens:
"Indirect call -> direct call from other "
"module %T=> %i (will resolve only with LTO)\n",
Current trunk returns false in that case.
>
> - if (!get_nth_most_common_value (NULL, "indirect call", histogram, &val,
> - &count, &all))
> - return false;
> + count = 0;
> + all = histogram->hvalue.counters[0];
>
> - if (4 * count <= 3 * all)
> - return false;
> + for (unsigned j = 0; j < GCOV_TOPN_VALUES; j++)
> + {
> + if (!get_nth_most_common_value (NULL, "indirect call", histogram, &val,
> + &count, &all, j))
> + continue;
You should break here as get_nth_most_common_value (..., j + 1) will also return
false.
>
> - direct_call = find_func_by_profile_id ((int)val);
> + /* Minimum probability. should be higher than 25%. */
> + if (4 * count <= all)
> + continue;
You can break here as well.
Thank you,
Martin
>
> - if (direct_call == NULL)
> - {
> - if (val)
> + direct_call = find_func_by_profile_id ((int) val);
> +
> + if (direct_call == NULL)
> + {
> + if (val)
> + {
> + if (dump_enabled_p ())
> + dump_printf_loc (
> + MSG_MISSED_OPTIMIZATION, stmt,
> + "Indirect call -> direct call from other "
> + "module %T=> %i (will resolve only with LTO)\n",
> + gimple_call_fn (stmt), (int) val);
> + }
> + continue;
> + }
> +
> + if (!check_ic_target (stmt, direct_call))
> {
> if (dump_enabled_p ())
> - dump_printf_loc (MSG_MISSED_OPTIMIZATION, stmt,
> - "Indirect call -> direct call from other "
> - "module %T=> %i (will resolve only with LTO)\n",
> - gimple_call_fn (stmt), (int)val);
> + dump_printf_loc (
> + MSG_MISSED_OPTIMIZATION, stmt,
> + "Indirect call -> direct call %T => %T "
> + "transformation skipped because of type mismatch: %G",
> + gimple_call_fn (stmt), direct_call->decl, stmt);
> + gimple_remove_histogram_value (cfun, stmt, histogram);
> + return false;
> }
> - return false;
> - }
>
> - if (!check_ic_target (stmt, direct_call))
> - {
> if (dump_enabled_p ())
> - dump_printf_loc (MSG_MISSED_OPTIMIZATION, stmt,
> - "Indirect call -> direct call %T => %T "
> - "transformation skipped because of type mismatch: %G",
> - gimple_call_fn (stmt), direct_call->decl, stmt);
> - gimple_remove_histogram_value (cfun, stmt, histogram);
> - return false;
> - }
> -
> - if (dump_enabled_p ())
> - {
> - dump_printf_loc (MSG_OPTIMIZED_LOCATIONS, stmt,
> - "Indirect call -> direct call "
> - "%T => %T transformation on insn postponed\n",
> - gimple_call_fn (stmt), direct_call->decl);
> - dump_printf_loc (MSG_NOTE, stmt,
> - "hist->count %" PRId64
> - " hist->all %" PRId64"\n", count, all);
> + {
> + dump_printf_loc (MSG_OPTIMIZED_LOCATIONS, stmt,
> + "Indirect call -> direct call "
> + "%T => %T transformation on insn postponed\n",
> + gimple_call_fn (stmt), direct_call->decl);
> + dump_printf_loc (MSG_NOTE, stmt,
> + "hist->count %" PRId64 " hist->all %" PRId64 "\n",
> + count, all);
> + }
> }
>
> return true;
>
diff --git a/gcc/cgraph.c b/gcc/cgraph.c
index 401e304984a..faabf0ef4bc 100644
--- a/gcc/cgraph.c
+++ b/gcc/cgraph.c
@@ -1381,7 +1381,7 @@ cgraph_edge::redirect_call_stmt_to_callee (void)
/* As the direct targets are sorted by decrease, delete the first
target when it is redirected. */
e2->indirect_info->indirect_call_targets->ordered_remove (0);
- if (!e2->indirect_info->indirect_call_targets->length ())
+ if (e2->indirect_info->indirect_call_targets->is_empty ())
e2->speculative = false;
}
else
@@ -3872,7 +3872,7 @@ bool
cgraph_edge::has_multiple_indirect_call_p (void)
{
return indirect_info && indirect_info->indirect_call_targets
- && indirect_info->indirect_call_targets->length () > 1;
+ && !indirect_info->indirect_call_targets->is_empty ();
}
/* Return true if this edge has at least one indirect call target. */
@@ -3880,7 +3880,7 @@ bool
cgraph_edge::has_indirect_call_p (void)
{
return indirect_info && indirect_info->indirect_call_targets
- && indirect_info->indirect_call_targets->length ();
+ && !indirect_info->indirect_call_targets->is_empty ();
}
/* A stashed copy of "symtab" for use by selftest::symbol_table_test.
