1 | /* Rich optional information on why an optimization wasn't possible. |
2 | Copyright (C) 2018-2024 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 under |
8 | the terms of the GNU General Public License as published by the Free |
9 | Software Foundation; either version 3, or (at your option) any later |
10 | version. |
11 | |
12 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY |
13 | WARRANTY; without even the implied warranty of MERCHANTABILITY or |
14 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
15 | 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 | #include "system.h" |
23 | #include "coretypes.h" |
24 | #include "backend.h" |
25 | #include "tree.h" |
26 | #include "gimple.h" |
27 | #include "pretty-print.h" |
28 | #include "opt-problem.h" |
29 | #include "dump-context.h" |
30 | #include "tree-pass.h" |
31 | #include "selftest.h" |
32 | |
33 | /* opt_problem's ctor. |
34 | |
35 | Use FMT and AP to emit a message to the "immediate" dump destinations |
36 | as if via: |
37 | dump_printf_loc (MSG_MISSED_OPTIMIZATION, loc, ...) |
38 | |
39 | The optinfo_item instances are not emitted yet. Instead, they |
40 | are retained internally so that the message can be replayed and |
41 | emitted when this problem is handled, higher up the call stack. */ |
42 | |
43 | opt_problem::opt_problem (const dump_location_t &loc, |
44 | const char *fmt, va_list *ap) |
45 | : m_optinfo (loc, OPTINFO_KIND_FAILURE, current_pass) |
46 | { |
47 | /* We shouldn't be bothering to construct these objects if |
48 | dumping isn't enabled. */ |
49 | gcc_assert (dump_enabled_p ()); |
50 | |
51 | /* Update the singleton. */ |
52 | delete s_the_problem; |
53 | s_the_problem = this; |
54 | |
55 | /* Print the location to the "immediate" dump destinations. */ |
56 | dump_context &dc = dump_context::get (); |
57 | dc.dump_loc (metadata: MSG_MISSED_OPTIMIZATION, loc: loc.get_user_location ()); |
58 | |
59 | /* Print the formatted string to this opt_problem's optinfo, dumping |
60 | the items to the "immediate" dump destinations, and storing items |
61 | for later retrieval. */ |
62 | { |
63 | dump_pretty_printer pp (&dump_context::get (), MSG_MISSED_OPTIMIZATION); |
64 | |
65 | text_info text (fmt, /* No i18n is performed. */ |
66 | ap, errno); |
67 | |
68 | /* Phases 1 and 2, using pp_format. */ |
69 | pp_format (&pp, &text); |
70 | |
71 | /* Phase 3: dump the items to the "immediate" dump destinations, |
72 | and storing them into m_optinfo for later retrieval. */ |
73 | pp.emit_items (dest: &m_optinfo); |
74 | } |
75 | } |
76 | |
77 | /* Emit this problem and delete it, clearing the current opt_problem. */ |
78 | |
79 | void |
80 | opt_problem::emit_and_clear () |
81 | { |
82 | gcc_assert (this == s_the_problem); |
83 | |
84 | m_optinfo.emit_for_opt_problem (); |
85 | |
86 | delete this; |
87 | s_the_problem = NULL; |
88 | } |
89 | |
90 | /* The singleton opt_problem *. */ |
91 | |
92 | opt_problem *opt_problem::s_the_problem; |
93 | |
94 | #if CHECKING_P |
95 | |
96 | namespace selftest { |
97 | |
98 | static opt_result |
99 | function_that_succeeds () |
100 | { |
101 | return opt_result::success (); |
102 | } |
103 | |
104 | /* Verify that opt_result::success works. */ |
105 | |
106 | static void |
107 | test_opt_result_success () |
108 | { |
109 | /* Run all tests twice, with and then without dumping enabled. */ |
110 | for (int i = 0 ; i < 2; i++) |
111 | { |
112 | bool with_dumping = (i == 0); |
113 | |
114 | temp_dump_context tmp (with_dumping, with_dumping, |
115 | MSG_ALL_KINDS | MSG_ALL_PRIORITIES); |
116 | |
117 | if (with_dumping) |
118 | gcc_assert (dump_enabled_p ()); |
119 | else |
120 | gcc_assert (!dump_enabled_p ()); |
121 | |
122 | opt_result res = function_that_succeeds (); |
123 | |
124 | /* Verify that "success" can be used as a "true" boolean. */ |
125 | ASSERT_TRUE (res); |
126 | |
127 | /* Verify the underlying opt_wrapper<bool>. */ |
128 | ASSERT_TRUE (res.get_result ()); |
129 | ASSERT_EQ (res.get_problem (), NULL); |
130 | |
131 | /* Nothing should have been dumped. */ |
132 | ASSERT_DUMPED_TEXT_EQ (tmp, "" ); |
133 | optinfo *info = tmp.get_pending_optinfo (); |
134 | ASSERT_EQ (info, NULL); |
135 | } |
136 | } |
137 | |
138 | /* Example of a function that fails, with a non-trivial |
139 | pre-canned error message. */ |
140 | |
141 | static opt_result |
142 | function_that_fails (const greturn *stmt) |
143 | { |
144 | gcc_assert (stmt); |
145 | gcc_assert (gimple_return_retval (stmt)); |
146 | |
147 | AUTO_DUMP_SCOPE ("function_that_fails" , stmt); |
148 | |
149 | return opt_result::failure_at (loc: stmt, |
150 | fmt: "can't handle return type: %T for stmt: %G" , |
151 | TREE_TYPE (gimple_return_retval (stmt)), |
152 | static_cast <const gimple *> (stmt)); |
153 | } |
154 | |
155 | /* Example of a function that indirectly fails. */ |
156 | |
157 | static opt_result |
158 | function_that_indirectly_fails (const greturn *stmt) |
159 | { |
160 | AUTO_DUMP_SCOPE ("function_that_indirectly_fails" , stmt); |
161 | |
162 | opt_result res = function_that_fails (stmt); |
163 | if (!res) |
164 | return res; |
165 | return opt_result::success (); |
166 | } |
167 | |
168 | /* Verify that opt_result::failure_at works. |
169 | Simulate a failure handling a stmt at one location whilst considering |
170 | an optimization that's notionally at another location (as a microcosm |
171 | of e.g. a problematic statement within a loop that prevents loop |
172 | vectorization). */ |
173 | |
174 | static void |
175 | test_opt_result_failure_at (const line_table_case &case_) |
176 | { |
177 | /* Generate a location_t for testing. */ |
178 | line_table_test ltt (case_); |
179 | const line_map_ordinary *ord_map |
180 | = linemap_check_ordinary (map: linemap_add (line_table, LC_ENTER, sysp: false, |
181 | to_file: "test.c" , to_line: 0)); |
182 | linemap_line_start (set: line_table, to_line: 5, max_column_hint: 100); |
183 | |
184 | /* A test location: "test.c:5:10". */ |
185 | const location_t line_5 = linemap_position_for_column (line_table, 10); |
186 | |
187 | /* Another test location: "test.c:6:12". */ |
188 | const location_t line_6 |
189 | = linemap_position_for_line_and_column (set: line_table, ord_map, 6, 12); |
190 | |
191 | if (line_6 > LINE_MAP_MAX_LOCATION_WITH_COLS) |
192 | return; |
193 | |
194 | /* Generate statements using "line_5" and "line_6" for testing. */ |
195 | greturn *stmt_at_5 = gimple_build_return (integer_one_node); |
196 | gimple_set_location (g: stmt_at_5, location: line_5); |
197 | |
198 | greturn *stmt_at_6 = gimple_build_return (integer_zero_node); |
199 | gimple_set_location (g: stmt_at_6, location: line_6); |
200 | |
201 | /* Run with and then without dumping enabled. */ |
202 | for (int i = 0; i < 2; i++) |
203 | { |
204 | bool with_dumping = (i == 0); |
205 | |
206 | /* Run with all 4 combinations of |
207 | with and without MSG_PRIORITY_INTERNALS and |
208 | with and without MSG_PRIORITY_REEMITTED. */ |
209 | for (int j = 0; j < 4; j++) |
210 | { |
211 | dump_flags_t filter = MSG_ALL_KINDS | MSG_PRIORITY_USER_FACING; |
212 | if (j / 2) |
213 | filter |= MSG_PRIORITY_INTERNALS; |
214 | if (j % 2) |
215 | filter |= MSG_PRIORITY_REEMITTED; |
216 | |
217 | temp_dump_context tmp (with_dumping, with_dumping, filter); |
218 | |
219 | if (with_dumping) |
220 | gcc_assert (dump_enabled_p ()); |
221 | else |
222 | gcc_assert (!dump_enabled_p ()); |
223 | |
224 | /* Simulate attempting to optimize "stmt_at_6". */ |
225 | opt_result res = function_that_indirectly_fails (stmt: stmt_at_6); |
226 | |
227 | /* Verify that "failure" can be used as a "false" boolean. */ |
228 | ASSERT_FALSE (res); |
229 | |
230 | /* Verify the underlying opt_wrapper<bool>. */ |
231 | ASSERT_FALSE (res.get_result ()); |
232 | opt_problem *problem = res.get_problem (); |
233 | |
234 | if (with_dumping) |
235 | { |
236 | ASSERT_NE (problem, NULL); |
237 | ASSERT_EQ (problem->get_dump_location ().get_location_t (), |
238 | line_6); |
239 | #if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 8) |
240 | /* Verify that the problem captures the implementation location |
241 | it was emitted from. */ |
242 | const dump_impl_location_t &impl_location |
243 | = problem->get_dump_location ().get_impl_location (); |
244 | ASSERT_STR_CONTAINS (impl_location.m_function, |
245 | "function_that_fails" ); |
246 | #endif |
247 | |
248 | /* Verify that the underlying dump items are retained in the |
249 | opt_problem. */ |
250 | const optinfo &info = problem->get_optinfo (); |
251 | ASSERT_EQ (info.get_dump_location ().get_location_t (), line_6); |
252 | ASSERT_EQ (info.num_items (), 4); |
253 | ASSERT_IS_TEXT (info.get_item (0), "can't handle return type: " ); |
254 | ASSERT_IS_TREE (info.get_item (1), UNKNOWN_LOCATION, "int" ); |
255 | ASSERT_IS_TEXT (info.get_item (2), " for stmt: " ); |
256 | ASSERT_IS_GIMPLE (info.get_item (3), line_6, "return 0;\n" ); |
257 | |
258 | /* ...but not in the dump_context's pending_optinfo. */ |
259 | ASSERT_EQ (tmp.get_pending_optinfo (), NULL); |
260 | |
261 | /* Simulate emitting a high-level summary message, followed |
262 | by the problem. */ |
263 | dump_printf_loc (MSG_MISSED_OPTIMIZATION, stmt_at_5, |
264 | "can't optimize loop\n" ); |
265 | problem->emit_and_clear (); |
266 | ASSERT_EQ (res.get_problem (), NULL); |
267 | |
268 | /* Verify that the error message was dumped (when the failure |
269 | occurred). We can't use a switch here as not all of the |
270 | values are const expressions (using C++98). */ |
271 | dump_flags_t effective_filter |
272 | = filter & (MSG_PRIORITY_INTERNALS | MSG_PRIORITY_REEMITTED); |
273 | if (effective_filter |
274 | == (MSG_PRIORITY_INTERNALS | MSG_PRIORITY_REEMITTED)) |
275 | /* The -fopt-info-internals case. */ |
276 | ASSERT_DUMPED_TEXT_EQ |
277 | (tmp, |
278 | "test.c:6:12: note: === function_that_indirectly_fails" |
279 | " ===\n" |
280 | "test.c:6:12: note: === function_that_fails ===\n" |
281 | "test.c:6:12: missed: can't handle return type: int" |
282 | " for stmt: return 0;\n" |
283 | "test.c:5:10: missed: can't optimize loop\n" |
284 | "test.c:6:12: missed: can't handle return type: int" |
285 | " for stmt: return 0;\n" ); |
286 | else if (effective_filter == MSG_PRIORITY_INTERNALS) |
287 | /* The default for dump files. */ |
288 | ASSERT_DUMPED_TEXT_EQ |
289 | (tmp, |
290 | "test.c:6:12: note: === function_that_indirectly_fails" |
291 | " ===\n" |
292 | "test.c:6:12: note: === function_that_fails ===\n" |
293 | "test.c:6:12: missed: can't handle return type: int" |
294 | " for stmt: return 0;\n" |
295 | "test.c:5:10: missed: can't optimize loop\n" ); |
296 | else if (effective_filter == MSG_PRIORITY_REEMITTED) |
297 | /* The default when -fopt-info is enabled. */ |
298 | ASSERT_DUMPED_TEXT_EQ |
299 | (tmp, |
300 | "test.c:5:10: missed: can't optimize loop\n" |
301 | "test.c:6:12: missed: can't handle return type: int" |
302 | " for stmt: return 0;\n" ); |
303 | else |
304 | { |
305 | gcc_assert (effective_filter == 0); |
306 | ASSERT_DUMPED_TEXT_EQ |
307 | (tmp, |
308 | "test.c:5:10: missed: can't optimize loop\n" ); |
309 | } |
310 | } |
311 | else |
312 | { |
313 | /* If dumping was disabled, then no problem should have been |
314 | created, and nothing should have been dumped. */ |
315 | ASSERT_EQ (problem, NULL); |
316 | ASSERT_DUMPED_TEXT_EQ (tmp, "" ); |
317 | } |
318 | } |
319 | } |
320 | } |
321 | |
322 | /* Run all of the selftests within this file. */ |
323 | |
324 | void |
325 | c_opt_problem_cc_tests () |
326 | { |
327 | test_opt_result_success (); |
328 | for_each_line_table_case (testcase: test_opt_result_failure_at); |
329 | } |
330 | |
331 | } // namespace selftest |
332 | |
333 | #endif /* CHECKING_P */ |
334 | |