1/* A class to encapsulate decisions about how the analysis should happen.
2 Copyright (C) 2019-2024 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 "config.h"
22#define INCLUDE_MEMORY
23#include "system.h"
24#include "coretypes.h"
25#include "tree.h"
26#include "options.h"
27#include "cgraph.h"
28#include "timevar.h"
29#include "ipa-utils.h"
30#include "function.h"
31#include "analyzer/analyzer.h"
32#include "diagnostic-core.h"
33#include "analyzer/analyzer-logging.h"
34#include "analyzer/analysis-plan.h"
35#include "ordered-hash-map.h"
36#include "options.h"
37#include "cgraph.h"
38#include "cfg.h"
39#include "basic-block.h"
40#include "gimple.h"
41#include "gimple-iterator.h"
42#include "digraph.h"
43#include "analyzer/supergraph.h"
44
45#if ENABLE_ANALYZER
46
47/* class analysis_plan. */
48
49/* analysis_plan's ctor. */
50
51analysis_plan::analysis_plan (const supergraph &sg, logger *logger)
52: log_user (logger), m_sg (sg),
53 m_cgraph_node_postorder (XCNEWVEC (struct cgraph_node *,
54 symtab->cgraph_count)),
55 m_index_by_uid (symtab->cgraph_max_uid)
56{
57 LOG_SCOPE (logger);
58 auto_timevar time (TV_ANALYZER_PLAN);
59
60 m_num_cgraph_nodes = ipa_reverse_postorder (m_cgraph_node_postorder);
61 gcc_assert (m_num_cgraph_nodes == symtab->cgraph_count);
62 if (get_logger_file ())
63 ipa_print_order (get_logger_file (),
64 "analysis_plan", m_cgraph_node_postorder,
65 m_num_cgraph_nodes);
66
67 /* Populate m_index_by_uid. */
68 for (int i = 0; i < symtab->cgraph_max_uid; i++)
69 m_index_by_uid.quick_push (obj: -1);
70 for (int i = 0; i < m_num_cgraph_nodes; i++)
71 {
72 gcc_assert (m_cgraph_node_postorder[i]->get_uid ()
73 < symtab->cgraph_max_uid);
74 m_index_by_uid[m_cgraph_node_postorder[i]->get_uid ()] = i;
75 }
76}
77
78/* analysis_plan's dtor. */
79
80analysis_plan::~analysis_plan ()
81{
82 free (ptr: m_cgraph_node_postorder);
83}
84
85/* Comparator for use by the exploded_graph's worklist, to order FUN_A
86 and FUN_B so that functions that are to be summarized are visited
87 before the summary is needed (based on a sort of the callgraph). */
88
89int
90analysis_plan::cmp_function (function *fun_a, function *fun_b) const
91{
92 cgraph_node *node_a = cgraph_node::get (decl: fun_a->decl);
93 cgraph_node *node_b = cgraph_node::get (decl: fun_b->decl);
94
95 int idx_a = m_index_by_uid[node_a->get_uid ()];
96 int idx_b = m_index_by_uid[node_b->get_uid ()];
97
98 return idx_b - idx_a;
99}
100
101/* Return true if the call EDGE should be analyzed using a call summary.
102 Return false if it should be analyzed using a full call and return. */
103
104bool
105analysis_plan::use_summary_p (const cgraph_edge *edge) const
106{
107 /* Don't use call summaries if -fno-analyzer-call-summaries. */
108 if (!flag_analyzer_call_summaries)
109 return false;
110
111 /* Don't use call summaries if there is no callgraph edge */
112 if (!edge || !edge->callee)
113 return false;
114
115 /* TODO: don't count callsites each time. */
116 int num_call_sites = 0;
117 const cgraph_node *callee = edge->callee;
118 for (cgraph_edge *edge = callee->callers; edge; edge = edge->next_caller)
119 ++num_call_sites;
120
121 /* Don't use a call summary if there's only one call site. */
122 if (num_call_sites <= 1)
123 return false;
124
125 /* Require the callee to be sufficiently complex to be worth
126 summarizing. */
127 const function *fun
128 = const_cast <cgraph_node *> (callee)->ultimate_alias_target ()->get_fun ();
129 /* TODO(stage1): can ultimate_alias_target be made const? */
130
131 if ((int)m_sg.get_num_snodes (fun)
132 < param_analyzer_min_snodes_for_call_summary)
133 return false;
134
135 return true;
136}
137
138#endif /* #if ENABLE_ANALYZER */
139

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