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 | |
5 | This file is part of GCC. |
6 | |
7 | GCC is free software; you can redistribute it and/or modify it |
8 | under the terms of the GNU General Public License as published by |
9 | the Free Software Foundation; either version 3, or (at your option) |
10 | any later version. |
11 | |
12 | GCC is distributed in the hope that it will be useful, but |
13 | WITHOUT ANY WARRANTY; without even the implied warranty of |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
15 | General Public License for more details. |
16 | |
17 | You should have received a copy of the GNU General Public License |
18 | along 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 | |
51 | analysis_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 | |
80 | analysis_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 | |
89 | int |
90 | analysis_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 | |
104 | bool |
105 | analysis_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 | |