1/* Unit tests for GCC's garbage collector (and gengtype etc).
2 Copyright (C) 2015-2017 Free Software Foundation, Inc.
3
4This file is part of GCC.
5
6GCC is free software; you can redistribute it and/or modify it under
7the terms of the GNU General Public License as published by the Free
8Software Foundation; either version 3, or (at your option) any later
9version.
10
11GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12WARRANTY; without even the implied warranty of MERCHANTABILITY or
13FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14for more details.
15
16You should have received a copy of the GNU General Public License
17along with GCC; see the file COPYING3. If not see
18<http://www.gnu.org/licenses/>. */
19
20#include "config.h"
21#include "system.h"
22#include "coretypes.h"
23#include "tree-core.h"
24#include "tree.h"
25#include "ggc-internal.h" /* (for ggc_force_collect). */
26#include "selftest.h"
27
28#if CHECKING_P
29
30/* A helper function for writing ggc tests. */
31
32void
33selftest::forcibly_ggc_collect ()
34{
35 ggc_force_collect = true;
36 ggc_collect ();
37 ggc_force_collect = false;
38}
39
40/* The various GTY markers must be outside of a namespace to be seen by
41 gengtype, so we don't put this file within the selftest namespace. */
42
43
44
45/* Verify that a simple struct works, and that it can
46 own references to non-roots, and have them be marked. */
47
48struct GTY(()) test_struct
49{
50 struct test_struct *other;
51};
52
53static GTY(()) test_struct *root_test_struct;
54
55static void
56test_basic_struct ()
57{
58 root_test_struct = ggc_cleared_alloc <test_struct> ();
59 root_test_struct->other = ggc_cleared_alloc <test_struct> ();
60
61 selftest::forcibly_ggc_collect ();
62
63 ASSERT_TRUE (ggc_marked_p (root_test_struct));
64 ASSERT_TRUE (ggc_marked_p (root_test_struct->other));
65}
66
67
68
69/* Selftest for GTY((length)). */
70
71/* A test struct using GTY((length)). */
72
73struct GTY(()) test_of_length
74{
75 int num_elem;
76 struct test_of_length * GTY ((length ("%h.num_elem"))) elem[1];
77};
78
79static GTY(()) test_of_length *root_test_of_length;
80
81static void
82test_length ()
83{
84 const int count = 5;
85 size_t sz = sizeof (test_of_length) + (count- 1) * sizeof (test_of_length *);
86 root_test_of_length = (test_of_length *)ggc_internal_cleared_alloc (sz);
87 root_test_of_length->num_elem = count;
88 for (int i = 0; i < count; i++)
89 root_test_of_length->elem[i] = ggc_cleared_alloc <test_of_length> ();
90
91 selftest::forcibly_ggc_collect ();
92
93 ASSERT_TRUE (ggc_marked_p (root_test_of_length));
94 for (int i = 0; i < count; i++)
95 ASSERT_TRUE (ggc_marked_p (root_test_of_length->elem[i]));
96}
97
98
99
100/* Selftest for unions, GTY((tag)), and GTY((desc)). */
101
102/* A struct with a reference that's an a different offset to test_struct,
103 to ensure that we're using the correct types. */
104
105struct GTY(()) test_other
106{
107 char dummy[256];
108 test_struct *m_ptr;
109};
110
111enum which_field
112{
113 WHICH_FIELD_USE_TEST_STRUCT,
114 WHICH_FIELD_USE_TEST_OTHER
115};
116
117/* An example function for use by a GTY((desc)) marker. */
118
119static enum which_field
120calc_desc (int kind)
121{
122 switch (kind)
123 {
124 case 0: return WHICH_FIELD_USE_TEST_STRUCT;
125 case 1: return WHICH_FIELD_USE_TEST_OTHER;
126 default:
127 gcc_unreachable ();
128 }
129}
130
131/* A struct containing an example of a union, showing the "tag" and
132 "desc" markers. */
133
134struct GTY(()) test_of_union
135{
136 int m_kind;
137 union u {
138 test_struct * GTY ((tag ("WHICH_FIELD_USE_TEST_STRUCT") )) u_test_struct;
139 test_other * GTY ((tag ("WHICH_FIELD_USE_TEST_OTHER") )) u_test_other;
140 } GTY ((desc ("calc_desc (%0.m_kind)"))) m_u;
141};
142
143/* Example roots. */
144
145static GTY(()) test_of_union *root_test_of_union_1;
146static GTY(()) test_of_union *root_test_of_union_2;
147
148/* Verify that the above work correctly. */
149
150static void
151test_union ()
152{
153 root_test_of_union_1 = ggc_cleared_alloc <test_of_union> ();
154 root_test_of_union_1->m_kind = 0;
155 test_struct *ts = ggc_cleared_alloc <test_struct> ();
156 root_test_of_union_1->m_u.u_test_struct = ts;
157
158 root_test_of_union_2 = ggc_cleared_alloc <test_of_union> ();
159 root_test_of_union_2->m_kind = 1;
160 test_other *other = ggc_cleared_alloc <test_other> ();
161 root_test_of_union_2->m_u.u_test_other = other;
162 test_struct *referenced_by_other = ggc_cleared_alloc <test_struct> ();
163 other->m_ptr = referenced_by_other;
164
165 selftest::forcibly_ggc_collect ();
166
167 ASSERT_TRUE (ggc_marked_p (root_test_of_union_1));
168 ASSERT_TRUE (ggc_marked_p (ts));
169
170 ASSERT_TRUE (ggc_marked_p (root_test_of_union_2));
171 ASSERT_TRUE (ggc_marked_p (other));
172 ASSERT_TRUE (ggc_marked_p (referenced_by_other));
173}
174
175
176
177/* Verify that destructors get run when instances are collected. */
178
179struct GTY(()) test_struct_with_dtor
180{
181 /* This struct has a destructor; it *ought* to be called
182 by the ggc machinery when instances are collected. */
183 ~test_struct_with_dtor () { dtor_call_count++; }
184
185 static int dtor_call_count;
186};
187
188int test_struct_with_dtor::dtor_call_count;
189
190static void
191test_finalization ()
192{
193#if GCC_VERSION >= 4003
194 ASSERT_FALSE (need_finalization_p <test_struct> ());
195 ASSERT_TRUE (need_finalization_p <test_struct_with_dtor> ());
196#endif
197
198 /* Create some garbage. */
199 const int count = 10;
200 for (int i = 0; i < count; i++)
201 ggc_cleared_alloc <test_struct_with_dtor> ();
202
203 test_struct_with_dtor::dtor_call_count = 0;
204
205 selftest::forcibly_ggc_collect ();
206
207 /* Verify that the destructor was run for each instance. */
208 ASSERT_EQ (count, test_struct_with_dtor::dtor_call_count);
209}
210
211
212
213/* Verify that a global can be marked as "deletable". */
214
215static GTY((deletable)) test_struct *test_of_deletable;
216
217static void
218test_deletable_global ()
219{
220 test_of_deletable = ggc_cleared_alloc <test_struct> ();
221 ASSERT_TRUE (test_of_deletable != NULL);
222
223 selftest::forcibly_ggc_collect ();
224
225 ASSERT_EQ (NULL, test_of_deletable);
226}
227
228
229
230/* Verify that gengtype etc can cope with inheritance. */
231
232class GTY((desc("%h.m_kind"), tag("0"))) example_base
233{
234 public:
235 example_base ()
236 : m_kind (0),
237 m_a (ggc_cleared_alloc <test_struct> ())
238 {}
239
240 void *
241 operator new (size_t sz)
242 {
243 return ggc_internal_cleared_alloc (sz);
244 }
245
246 protected:
247 example_base (int kind)
248 : m_kind (kind),
249 m_a (ggc_cleared_alloc <test_struct> ())
250 {}
251
252 public:
253 int m_kind;
254 test_struct *m_a;
255};
256
257class GTY((tag("1"))) some_subclass : public example_base
258{
259 public:
260 some_subclass ()
261 : example_base (1),
262 m_b (ggc_cleared_alloc <test_struct> ())
263 {}
264
265 test_struct *m_b;
266};
267
268class GTY((tag("2"))) some_other_subclass : public example_base
269{
270 public:
271 some_other_subclass ()
272 : example_base (2),
273 m_c (ggc_cleared_alloc <test_struct> ())
274 {}
275
276 test_struct *m_c;
277};
278
279/* Various test roots, both expressed as a ptr to the actual class, and
280 as a ptr to the base class. */
281static GTY(()) example_base *test_example_base;
282static GTY(()) some_subclass *test_some_subclass;
283static GTY(()) some_other_subclass *test_some_other_subclass;
284static GTY(()) example_base *test_some_subclass_as_base_ptr;
285static GTY(()) example_base *test_some_other_subclass_as_base_ptr;
286
287static void
288test_inheritance ()
289{
290 test_example_base = new example_base ();
291 test_some_subclass = new some_subclass ();
292 test_some_other_subclass = new some_other_subclass ();
293 test_some_subclass_as_base_ptr = new some_subclass ();
294 test_some_other_subclass_as_base_ptr = new some_other_subclass ();
295
296 selftest::forcibly_ggc_collect ();
297
298 /* Verify that the roots and everything referenced by them got marked
299 (both for fields in the base class and those in subclasses). */
300 ASSERT_TRUE (ggc_marked_p (test_example_base));
301 ASSERT_TRUE (ggc_marked_p (test_example_base->m_a));
302
303 ASSERT_TRUE (ggc_marked_p (test_some_subclass));
304 ASSERT_TRUE (ggc_marked_p (test_some_subclass->m_a));
305 ASSERT_TRUE (ggc_marked_p (test_some_subclass->m_b));
306
307 ASSERT_TRUE (ggc_marked_p (test_some_other_subclass));
308 ASSERT_TRUE (ggc_marked_p (test_some_other_subclass->m_a));
309 ASSERT_TRUE (ggc_marked_p (test_some_other_subclass->m_c));
310
311 ASSERT_TRUE (ggc_marked_p (test_some_subclass_as_base_ptr));
312 ASSERT_TRUE (ggc_marked_p (test_some_subclass_as_base_ptr->m_a));
313 ASSERT_TRUE (ggc_marked_p (((some_subclass *)
314 test_some_subclass_as_base_ptr)->m_b));
315
316 ASSERT_TRUE (ggc_marked_p (test_some_other_subclass_as_base_ptr));
317 ASSERT_TRUE (ggc_marked_p (test_some_other_subclass_as_base_ptr->m_a));
318 ASSERT_TRUE (ggc_marked_p (((some_other_subclass *)
319 test_some_other_subclass_as_base_ptr)->m_c));
320}
321
322
323
324/* Test of chain_next/chain_prev
325
326 Construct a very long linked list, so that without
327 the chain_next/chain_prev optimization we'd have
328 a stack overflow when gt_ggc_mx_test_node recurses. */
329
330struct GTY(( chain_next ("%h.m_next"),
331 chain_prev ("%h.m_prev") )) test_node
332{
333 test_node *m_prev;
334 test_node *m_next;
335 int m_idx;
336};
337
338static GTY(()) test_node *root_test_node;
339
340static void
341test_chain_next ()
342{
343 /* Ideally we would construct a long list so that the number of
344 stack frames would be deep enough to crash if gengtype has created
345 something that recurses.
346
347 However, as the list is lengthened to increase the chance of
348 overflowing the stack, the test will require more time and memory
349 to run. On a Fedora 20 x86_64 box with 128GB of RAM, count=2000000
350 without the chain_next optimization reliably overflowed the stack,
351 but the test took 0.5s to run.
352
353 For now this test runs with a low value for "count", which defeats
354 the main purpose of the test - though it at least gives us coverage
355 for walking a GTY((chain_next)) list.
356
357 We could potentially increase this value once we have a better sense
358 of the time and space requirements of the test on different hosts,
359 or perhaps find a way to reduce the stack size when running this
360 testcase. */
361 const int count = 10;
362
363 /* Build the linked list. */
364 root_test_node = ggc_cleared_alloc <test_node> ();
365 test_node *tail_node = root_test_node;
366 for (int i = 0; i < count; i++)
367 {
368 test_node *new_node = ggc_cleared_alloc <test_node> ();
369 tail_node->m_next = new_node;
370 new_node->m_prev = tail_node;
371 new_node->m_idx = i;
372 tail_node = new_node;
373 }
374
375 selftest::forcibly_ggc_collect ();
376
377 /* If we got here, we survived. */
378
379 /* Verify that all nodes in the list were marked. */
380 ASSERT_TRUE (ggc_marked_p (root_test_node));
381 test_node *iter_node = root_test_node->m_next;
382 for (int i = 0; i < count; i++)
383 {
384 ASSERT_TRUE (ggc_marked_p (iter_node));
385 ASSERT_EQ (i, iter_node->m_idx);
386 iter_node = iter_node->m_next;
387 }
388}
389
390
391
392/* Test for GTY((user)). */
393
394struct GTY((user)) user_struct
395{
396 char dummy[16];
397 test_struct *m_ptr;
398};
399
400static GTY(()) user_struct *root_user_struct_ptr;
401
402/* A global for verifying that the user-provided gt_ggc_mx gets
403 called. */
404static int num_calls_to_user_gt_ggc_mx;
405
406/* User-provided implementation of gt_ggc_mx. */
407
408static void
409gt_ggc_mx (user_struct *p)
410{
411 num_calls_to_user_gt_ggc_mx++;
412 gt_ggc_mx_test_struct (p->m_ptr);
413}
414
415/* User-provided implementation of gt_pch_nx. */
416
417static void
418gt_pch_nx (user_struct *p)
419{
420 gt_pch_nx_test_struct (p->m_ptr);
421}
422
423/* User-provided implementation of gt_pch_nx. */
424
425static void
426gt_pch_nx (user_struct *p, gt_pointer_operator op, void *cookie)
427{
428 op (&(p->m_ptr), cookie);
429}
430
431/* Verify that GTY((user)) works. */
432
433static void
434test_user_struct ()
435{
436 root_user_struct_ptr = ggc_cleared_alloc <user_struct> ();
437 test_struct *referenced = ggc_cleared_alloc <test_struct> ();
438 root_user_struct_ptr->m_ptr = referenced;
439
440 num_calls_to_user_gt_ggc_mx = 0;
441
442 selftest::forcibly_ggc_collect ();
443
444 ASSERT_TRUE (ggc_marked_p (root_user_struct_ptr));
445 ASSERT_TRUE (ggc_marked_p (referenced));
446 ASSERT_TRUE (num_calls_to_user_gt_ggc_mx > 0);
447}
448
449
450
451/* Smoketest to ensure that the tree type is marked. */
452
453static GTY(()) tree dummy_unittesting_tree;
454
455static void
456test_tree_marking ()
457{
458 dummy_unittesting_tree = build_int_cst (integer_type_node, 1066);
459
460 selftest::forcibly_ggc_collect ();
461
462 ASSERT_TRUE (ggc_marked_p (dummy_unittesting_tree));
463}
464
465
466
467/* Ideas for other tests:
468 - pch-handling */
469
470namespace selftest {
471
472/* Run all of the selftests within this file. */
473
474void
475ggc_tests_c_tests ()
476{
477 test_basic_struct ();
478 test_length ();
479 test_union ();
480 test_finalization ();
481 test_deletable_global ();
482 test_inheritance ();
483 test_chain_next ();
484 test_user_struct ();
485 test_tree_marking ();
486}
487
488} // namespace selftest
489
490#include "gt-ggc-tests.h"
491
492#else /* #if CHECKING_P */
493
494/* The #if CHECKING_P code above has various GTY-marked roots.
495 gengtype has no knowledge of the preprocessor, and so detects
496 these roots and writes them out to gt-ggc-tests.h.
497 In a !CHECKING_P build we can ignore gt-ggc-tests.h, but the
498 root tables are referenced in the various generated gtype-*.c
499 files like this:
500
501 ...snip...
502 extern const struct ggc_root_tab gt_ggc_r_gt_ggc_tests_h[];
503 ...snip...
504
505 EXPORTED_CONST struct ggc_root_tab * const gt_ggc_rtab[] = {
506 ...snip...
507 gt_ggc_r_gt_ggc_tests_h,
508 ...snip...
509 };
510
511 Hence to avoid a link failure, we provide dummy implementations
512 of these root tables in an unchecked build.
513
514 Note that these conditional roots imply that PCH files are
515 incompatible between checked and unchecked builds. */
516
517EXPORTED_CONST struct ggc_root_tab gt_ggc_r_gt_ggc_tests_h[] = {
518 LAST_GGC_ROOT_TAB
519};
520
521EXPORTED_CONST struct ggc_root_tab gt_ggc_rd_gt_ggc_tests_h[] = {
522 LAST_GGC_ROOT_TAB
523};
524
525#endif /* #else clause of #if CHECKING_P */
526