1/* A class to encapsulate decisions about how the analysis should happen.
2 Copyright (C) 2019-2025 Free Software Foundation, Inc.
3 Contributed by David Malcolm <dmalcolm@redhat.com>.
4
5This file is part of GCC.
6
7GCC is free software; you can redistribute it and/or modify it
8under the terms of the GNU General Public License as published by
9the Free Software Foundation; either version 3, or (at your option)
10any later version.
11
12GCC is distributed in the hope that it will be useful, but
13WITHOUT ANY WARRANTY; without even the implied warranty of
14MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15General Public License for more details.
16
17You should have received a copy of the GNU General Public License
18along with GCC; see the file COPYING3. If not see
19<http://www.gnu.org/licenses/>. */
20
21#include "analyzer/common.h"
22
23#include "timevar.h"
24#include "ordered-hash-map.h"
25#include "options.h"
26#include "cgraph.h"
27#include "cfg.h"
28#include "gimple-iterator.h"
29#include "digraph.h"
30#include "ipa-utils.h"
31
32#include "analyzer/analyzer-logging.h"
33#include "analyzer/analysis-plan.h"
34#include "analyzer/supergraph.h"
35
36#if ENABLE_ANALYZER
37
38/* class analysis_plan. */
39
40/* analysis_plan's ctor. */
41
42analysis_plan::analysis_plan (const supergraph &sg, logger *logger)
43: log_user (logger), m_sg (sg),
44 m_cgraph_node_postorder (XCNEWVEC (struct cgraph_node *,
45 symtab->cgraph_count)),
46 m_index_by_uid (symtab->cgraph_max_uid)
47{
48 LOG_SCOPE (logger);
49 auto_timevar time (TV_ANALYZER_PLAN);
50
51 m_num_cgraph_nodes = ipa_reverse_postorder (m_cgraph_node_postorder);
52 gcc_assert (m_num_cgraph_nodes == symtab->cgraph_count);
53 if (get_logger_file ())
54 ipa_print_order (get_logger_file (),
55 "analysis_plan", m_cgraph_node_postorder,
56 m_num_cgraph_nodes);
57
58 /* Populate m_index_by_uid. */
59 for (int i = 0; i < symtab->cgraph_max_uid; i++)
60 m_index_by_uid.quick_push (obj: -1);
61 for (int i = 0; i < m_num_cgraph_nodes; i++)
62 {
63 gcc_assert (m_cgraph_node_postorder[i]->get_uid ()
64 < symtab->cgraph_max_uid);
65 m_index_by_uid[m_cgraph_node_postorder[i]->get_uid ()] = i;
66 }
67}
68
69/* analysis_plan's dtor. */
70
71analysis_plan::~analysis_plan ()
72{
73 free (ptr: m_cgraph_node_postorder);
74}
75
76/* Comparator for use by the exploded_graph's worklist, to order FUN_A
77 and FUN_B so that functions that are to be summarized are visited
78 before the summary is needed (based on a sort of the callgraph). */
79
80int
81analysis_plan::cmp_function (function *fun_a, function *fun_b) const
82{
83 cgraph_node *node_a = cgraph_node::get (decl: fun_a->decl);
84 cgraph_node *node_b = cgraph_node::get (decl: fun_b->decl);
85
86 int idx_a = m_index_by_uid[node_a->get_uid ()];
87 int idx_b = m_index_by_uid[node_b->get_uid ()];
88
89 return idx_b - idx_a;
90}
91
92/* Return true if the call EDGE should be analyzed using a call summary.
93 Return false if it should be analyzed using a full call and return. */
94
95bool
96analysis_plan::use_summary_p (const cgraph_edge *edge) const
97{
98 /* Don't use call summaries if -fno-analyzer-call-summaries. */
99 if (!flag_analyzer_call_summaries)
100 return false;
101
102 /* Don't use call summaries if there is no callgraph edge */
103 if (!edge || !edge->callee)
104 return false;
105
106 /* TODO: don't count callsites each time. */
107 int num_call_sites = 0;
108 const cgraph_node *callee = edge->callee;
109 for (cgraph_edge *edge = callee->callers; edge; edge = edge->next_caller)
110 ++num_call_sites;
111
112 /* Don't use a call summary if there's only one call site. */
113 if (num_call_sites <= 1)
114 return false;
115
116 /* Require the callee to be sufficiently complex to be worth
117 summarizing. */
118 const function *fun
119 = const_cast <cgraph_node *> (callee)->ultimate_alias_target ()->get_fun ();
120 /* TODO(stage1): can ultimate_alias_target be made const? */
121
122 if ((int)m_sg.get_num_snodes (fun)
123 < param_analyzer_min_snodes_for_call_summary)
124 return false;
125
126 return true;
127}
128
129#endif /* #if ENABLE_ANALYZER */
130

source code of gcc/analyzer/analysis-plan.cc