1 /*===- GCDAProfiling.c - Support library for GCDA file emission -----------===*\
2 |*
3 |* Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 |* See https://llvm.org/LICENSE.txt for license information.
5 |* SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 |*
7 |*===----------------------------------------------------------------------===*|
8 |*
9 |* This file implements the call back routines for the gcov profiling
10 |* instrumentation pass. Link against this library when running code through
11 |* the -insert-gcov-profiling LLVM pass.
12 |*
13 |* We emit files in a corrupt version of GCOV's "gcda" file format. These files
14 |* are only close enough that LCOV will happily parse them. Anything that lcov
15 |* ignores is missing.
16 |*
17 |* TODO: gcov is multi-process safe by having each exit open the existing file
18 |* and append to it. We'd like to achieve that and be thread-safe too.
19 |*
20 \*===----------------------------------------------------------------------===*/
21
22 #if !defined(__Fuchsia__)
23
24 #include <errno.h>
25 #include <fcntl.h>
26 #include <stdio.h>
27 #include <stdlib.h>
28 #include <string.h>
29
30 #if defined(_WIN32)
31 #define WIN32_LEAN_AND_MEAN
32 #include <windows.h>
33 #include "WindowsMMap.h"
34 #else
35 #include <sys/file.h>
36 #include <sys/mman.h>
37 #include <sys/types.h>
38 #include <unistd.h>
39 #endif
40
41 #if defined(__FreeBSD__) && defined(__i386__)
42 #define I386_FREEBSD 1
43 #else
44 #define I386_FREEBSD 0
45 #endif
46
47 #if !defined(_MSC_VER) && !I386_FREEBSD
48 #include <stdint.h>
49 #endif
50
51 #if defined(_MSC_VER)
52 typedef unsigned char uint8_t;
53 typedef unsigned int uint32_t;
54 typedef unsigned long long uint64_t;
55 #elif I386_FREEBSD
56 /* System headers define 'size_t' incorrectly on x64 FreeBSD (prior to
57 * FreeBSD 10, r232261) when compiled in 32-bit mode.
58 */
59 typedef unsigned char uint8_t;
60 typedef unsigned int uint32_t;
61 typedef unsigned long long uint64_t;
62 #endif
63
64 #include "InstrProfiling.h"
65 #include "InstrProfilingUtil.h"
66
67 /* #define DEBUG_GCDAPROFILING */
68
69 enum {
70 GCOV_DATA_MAGIC = 0x67636461, // "gcda"
71
72 GCOV_TAG_FUNCTION = 0x01000000,
73 GCOV_TAG_COUNTER_ARCS = 0x01a10000,
74 // GCOV_TAG_OBJECT_SUMMARY superseded GCOV_TAG_PROGRAM_SUMMARY in GCC 9.
75 GCOV_TAG_OBJECT_SUMMARY = 0xa1000000,
76 GCOV_TAG_PROGRAM_SUMMARY = 0xa3000000,
77 };
78
79 /*
80 * --- GCOV file format I/O primitives ---
81 */
82
83 /*
84 * The current file name we're outputting. Used primarily for error logging.
85 */
86 static char *filename = NULL;
87
88 /*
89 * The current file we're outputting.
90 */
91 static FILE *output_file = NULL;
92
93 /*
94 * Buffer that we write things into.
95 */
96 #define WRITE_BUFFER_SIZE (128 * 1024)
97 static unsigned char *write_buffer = NULL;
98 static uint64_t cur_buffer_size = 0;
99 static uint64_t cur_pos = 0;
100 static uint64_t file_size = 0;
101 static int new_file = 0;
102 static int gcov_version;
103 #if defined(_WIN32)
104 static HANDLE mmap_handle = NULL;
105 #endif
106 static int fd = -1;
107
108 typedef void (*fn_ptr)();
109
110 typedef void* dynamic_object_id;
111 // The address of this variable identifies a given dynamic object.
112 static dynamic_object_id current_id;
113 #define CURRENT_ID (¤t_id)
114
115 struct fn_node {
116 dynamic_object_id id;
117 fn_ptr fn;
118 struct fn_node* next;
119 };
120
121 struct fn_list {
122 struct fn_node *head, *tail;
123 };
124
125 /*
126 * A list of functions to write out the data, shared between all dynamic objects.
127 */
128 struct fn_list writeout_fn_list;
129
130 /*
131 * A list of flush functions that our __gcov_flush() function should call, shared between all dynamic objects.
132 */
133 struct fn_list flush_fn_list;
134
135 /*
136 * A list of reset functions, shared between all dynamic objects.
137 */
138 struct fn_list reset_fn_list;
139
fn_list_insert(struct fn_list * list,fn_ptr fn)140 static void fn_list_insert(struct fn_list* list, fn_ptr fn) {
141 struct fn_node* new_node = malloc(sizeof(struct fn_node));
142 new_node->fn = fn;
143 new_node->next = NULL;
144 new_node->id = CURRENT_ID;
145
146 if (!list->head) {
147 list->head = list->tail = new_node;
148 } else {
149 list->tail->next = new_node;
150 list->tail = new_node;
151 }
152 }
153
fn_list_remove(struct fn_list * list)154 static void fn_list_remove(struct fn_list* list) {
155 struct fn_node* curr = list->head;
156 struct fn_node* prev = NULL;
157 struct fn_node* next = NULL;
158
159 while (curr) {
160 next = curr->next;
161
162 if (curr->id == CURRENT_ID) {
163 if (curr == list->head) {
164 list->head = next;
165 }
166
167 if (curr == list->tail) {
168 list->tail = prev;
169 }
170
171 if (prev) {
172 prev->next = next;
173 }
174
175 free(curr);
176 } else {
177 prev = curr;
178 }
179
180 curr = next;
181 }
182 }
183
resize_write_buffer(uint64_t size)184 static void resize_write_buffer(uint64_t size) {
185 if (!new_file) return;
186 size += cur_pos;
187 if (size <= cur_buffer_size) return;
188 size = (size - 1) / WRITE_BUFFER_SIZE + 1;
189 size *= WRITE_BUFFER_SIZE;
190 write_buffer = realloc(write_buffer, size);
191 cur_buffer_size = size;
192 }
193
write_bytes(const char * s,size_t len)194 static void write_bytes(const char *s, size_t len) {
195 resize_write_buffer(len);
196 memcpy(&write_buffer[cur_pos], s, len);
197 cur_pos += len;
198 }
199
write_32bit_value(uint32_t i)200 static void write_32bit_value(uint32_t i) {
201 write_bytes((char*)&i, 4);
202 }
203
write_64bit_value(uint64_t i)204 static void write_64bit_value(uint64_t i) {
205 // GCOV uses a lo-/hi-word format even on big-endian systems.
206 // See also GCOVBuffer::readInt64 in LLVM.
207 uint32_t lo = (uint32_t) i;
208 uint32_t hi = (uint32_t) (i >> 32);
209 write_32bit_value(lo);
210 write_32bit_value(hi);
211 }
212
length_of_string(const char * s)213 static uint32_t length_of_string(const char *s) {
214 return (strlen(s) / 4) + 1;
215 }
216
217 // Remove when we support libgcov 9 current_working_directory.
218 #if !defined(_MSC_VER) && defined(__clang__)
219 __attribute__((unused))
220 #endif
221 static void
write_string(const char * s)222 write_string(const char *s) {
223 uint32_t len = length_of_string(s);
224 write_32bit_value(len);
225 write_bytes(s, strlen(s));
226 write_bytes("\0\0\0\0", 4 - (strlen(s) % 4));
227 }
228
read_32bit_value()229 static uint32_t read_32bit_value() {
230 uint32_t val;
231
232 if (new_file)
233 return (uint32_t)-1;
234
235 val = *(uint32_t*)&write_buffer[cur_pos];
236 cur_pos += 4;
237 return val;
238 }
239
read_64bit_value()240 static uint64_t read_64bit_value() {
241 // GCOV uses a lo-/hi-word format even on big-endian systems.
242 // See also GCOVBuffer::readInt64 in LLVM.
243 uint32_t lo = read_32bit_value();
244 uint32_t hi = read_32bit_value();
245 return ((uint64_t)hi << 32) | ((uint64_t)lo);
246 }
247
mangle_filename(const char * orig_filename)248 static char *mangle_filename(const char *orig_filename) {
249 char *new_filename;
250 size_t prefix_len;
251 int prefix_strip;
252 const char *prefix = lprofGetPathPrefix(&prefix_strip, &prefix_len);
253
254 if (prefix == NULL)
255 return strdup(orig_filename);
256
257 new_filename = malloc(prefix_len + 1 + strlen(orig_filename) + 1);
258 lprofApplyPathPrefix(new_filename, orig_filename, prefix, prefix_len,
259 prefix_strip);
260
261 return new_filename;
262 }
263
map_file()264 static int map_file() {
265 fseek(output_file, 0L, SEEK_END);
266 file_size = ftell(output_file);
267
268 /* A size of 0 means the file has been created just now (possibly by another
269 * process in lock-after-open race condition). No need to mmap. */
270 if (file_size == 0)
271 return -1;
272
273 #if defined(_WIN32)
274 HANDLE mmap_fd;
275 if (fd == -1)
276 mmap_fd = INVALID_HANDLE_VALUE;
277 else
278 mmap_fd = (HANDLE)_get_osfhandle(fd);
279
280 mmap_handle = CreateFileMapping(mmap_fd, NULL, PAGE_READWRITE, DWORD_HI(file_size), DWORD_LO(file_size), NULL);
281 if (mmap_handle == NULL) {
282 fprintf(stderr, "profiling: %s: cannot create file mapping: %lu\n",
283 filename, GetLastError());
284 return -1;
285 }
286
287 write_buffer = MapViewOfFile(mmap_handle, FILE_MAP_WRITE, 0, 0, file_size);
288 if (write_buffer == NULL) {
289 fprintf(stderr, "profiling: %s: cannot map: %lu\n", filename,
290 GetLastError());
291 CloseHandle(mmap_handle);
292 return -1;
293 }
294 #else
295 write_buffer = mmap(0, file_size, PROT_READ | PROT_WRITE,
296 MAP_FILE | MAP_SHARED, fd, 0);
297 if (write_buffer == (void *)-1) {
298 int errnum = errno;
299 fprintf(stderr, "profiling: %s: cannot map: %s\n", filename,
300 strerror(errnum));
301 return -1;
302 }
303 #endif
304
305 return 0;
306 }
307
unmap_file()308 static void unmap_file() {
309 #if defined(_WIN32)
310 if (!FlushViewOfFile(write_buffer, file_size)) {
311 fprintf(stderr, "profiling: %s: cannot flush mapped view: %lu\n", filename,
312 GetLastError());
313 }
314
315 if (!UnmapViewOfFile(write_buffer)) {
316 fprintf(stderr, "profiling: %s: cannot unmap mapped view: %lu\n", filename,
317 GetLastError());
318 }
319
320 if (!CloseHandle(mmap_handle)) {
321 fprintf(stderr, "profiling: %s: cannot close file mapping handle: %lu\n",
322 filename, GetLastError());
323 }
324
325 mmap_handle = NULL;
326 #else
327 if (msync(write_buffer, file_size, MS_SYNC) == -1) {
328 int errnum = errno;
329 fprintf(stderr, "profiling: %s: cannot msync: %s\n", filename,
330 strerror(errnum));
331 }
332
333 /* We explicitly ignore errors from unmapping because at this point the data
334 * is written and we don't care.
335 */
336 (void)munmap(write_buffer, file_size);
337 #endif
338
339 write_buffer = NULL;
340 file_size = 0;
341 }
342
343 /*
344 * --- LLVM line counter API ---
345 */
346
347 /* A file in this case is a translation unit. Each .o file built with line
348 * profiling enabled will emit to a different file. Only one file may be
349 * started at a time.
350 */
351 COMPILER_RT_VISIBILITY
llvm_gcda_start_file(const char * orig_filename,uint32_t version,uint32_t checksum)352 void llvm_gcda_start_file(const char *orig_filename, uint32_t version,
353 uint32_t checksum) {
354 const char *mode = "r+b";
355 filename = mangle_filename(orig_filename);
356
357 /* Try just opening the file. */
358 fd = open(filename, O_RDWR | O_BINARY);
359
360 if (fd == -1) {
361 /* Try creating the file. */
362 fd = open(filename, O_RDWR | O_CREAT | O_EXCL | O_BINARY, 0644);
363 if (fd != -1) {
364 mode = "w+b";
365 } else {
366 /* Try creating the directories first then opening the file. */
367 __llvm_profile_recursive_mkdir(filename);
368 fd = open(filename, O_RDWR | O_CREAT | O_EXCL | O_BINARY, 0644);
369 if (fd != -1) {
370 mode = "w+b";
371 } else {
372 /* Another process may have created the file just now.
373 * Try opening it without O_CREAT and O_EXCL. */
374 fd = open(filename, O_RDWR | O_BINARY);
375 if (fd == -1) {
376 /* Bah! It's hopeless. */
377 int errnum = errno;
378 fprintf(stderr, "profiling: %s: cannot open: %s\n", filename,
379 strerror(errnum));
380 return;
381 }
382 }
383 }
384 }
385
386 /* Try to flock the file to serialize concurrent processes writing out to the
387 * same GCDA. This can fail if the filesystem doesn't support it, but in that
388 * case we'll just carry on with the old racy behaviour and hope for the best.
389 */
390 lprofLockFd(fd);
391 output_file = fdopen(fd, mode);
392
393 /* Initialize the write buffer. */
394 new_file = 0;
395 write_buffer = NULL;
396 cur_buffer_size = 0;
397 cur_pos = 0;
398
399 if (map_file() == -1) {
400 /* The file has been created just now (file_size == 0) or mmap failed
401 * unexpectedly. In the latter case, try to recover by clobbering. */
402 new_file = 1;
403 write_buffer = NULL;
404 resize_write_buffer(WRITE_BUFFER_SIZE);
405 memset(write_buffer, 0, WRITE_BUFFER_SIZE);
406 }
407
408 /* gcda file, version, stamp checksum. */
409 {
410 uint8_t c3 = version >> 24;
411 uint8_t c2 = (version >> 16) & 255;
412 uint8_t c1 = (version >> 8) & 255;
413 gcov_version = c3 >= 'A' ? (c3 - 'A') * 100 + (c2 - '0') * 10 + c1 - '0'
414 : (c3 - '0') * 10 + c1 - '0';
415 }
416 write_32bit_value(GCOV_DATA_MAGIC);
417 write_32bit_value(version);
418 write_32bit_value(checksum);
419
420 #ifdef DEBUG_GCDAPROFILING
421 fprintf(stderr, "llvmgcda: [%s]\n", orig_filename);
422 #endif
423 }
424
425 /* Given an array of pointers to counters (counters), increment the n-th one,
426 * where we're also given a pointer to n (predecessor).
427 */
428 COMPILER_RT_VISIBILITY
llvm_gcda_increment_indirect_counter(uint32_t * predecessor,uint64_t ** counters)429 void llvm_gcda_increment_indirect_counter(uint32_t *predecessor,
430 uint64_t **counters) {
431 uint64_t *counter;
432 uint32_t pred;
433
434 pred = *predecessor;
435 if (pred == 0xffffffff)
436 return;
437 counter = counters[pred];
438
439 /* Don't crash if the pred# is out of sync. This can happen due to threads,
440 or because of a TODO in GCOVProfiling.cpp buildEdgeLookupTable(). */
441 if (counter)
442 ++*counter;
443 #ifdef DEBUG_GCDAPROFILING
444 else
445 fprintf(stderr,
446 "llvmgcda: increment_indirect_counter counters=%08llx, pred=%u\n",
447 *counter, *predecessor);
448 #endif
449 }
450
451 COMPILER_RT_VISIBILITY
llvm_gcda_emit_function(uint32_t ident,uint32_t func_checksum,uint32_t cfg_checksum)452 void llvm_gcda_emit_function(uint32_t ident, uint32_t func_checksum,
453 uint32_t cfg_checksum) {
454 uint32_t len = 2;
455 int use_extra_checksum = gcov_version >= 47;
456
457 if (use_extra_checksum)
458 len++;
459 #ifdef DEBUG_GCDAPROFILING
460 fprintf(stderr, "llvmgcda: function id=0x%08x\n", ident);
461 #endif
462 if (!output_file) return;
463
464 /* function tag */
465 write_32bit_value(GCOV_TAG_FUNCTION);
466 write_32bit_value(len);
467 write_32bit_value(ident);
468 write_32bit_value(func_checksum);
469 if (use_extra_checksum)
470 write_32bit_value(cfg_checksum);
471 }
472
473 COMPILER_RT_VISIBILITY
llvm_gcda_emit_arcs(uint32_t num_counters,uint64_t * counters)474 void llvm_gcda_emit_arcs(uint32_t num_counters, uint64_t *counters) {
475 uint32_t i;
476 uint64_t *old_ctrs = NULL;
477 uint32_t val = 0;
478 uint64_t save_cur_pos = cur_pos;
479
480 if (!output_file) return;
481
482 val = read_32bit_value();
483
484 if (val != (uint32_t)-1) {
485 /* There are counters present in the file. Merge them. */
486 if (val != GCOV_TAG_COUNTER_ARCS) {
487 fprintf(stderr, "profiling: %s: cannot merge previous GCDA file: "
488 "corrupt arc tag (0x%08x)\n",
489 filename, val);
490 return;
491 }
492
493 val = read_32bit_value();
494 if (val == (uint32_t)-1 || val / 2 != num_counters) {
495 fprintf(stderr, "profiling: %s: cannot merge previous GCDA file: "
496 "mismatched number of counters (%d)\n",
497 filename, val);
498 return;
499 }
500
501 old_ctrs = malloc(sizeof(uint64_t) * num_counters);
502 for (i = 0; i < num_counters; ++i)
503 old_ctrs[i] = read_64bit_value();
504 }
505
506 cur_pos = save_cur_pos;
507
508 /* Counter #1 (arcs) tag */
509 write_32bit_value(GCOV_TAG_COUNTER_ARCS);
510 write_32bit_value(num_counters * 2);
511 for (i = 0; i < num_counters; ++i) {
512 counters[i] += (old_ctrs ? old_ctrs[i] : 0);
513 write_64bit_value(counters[i]);
514 }
515
516 free(old_ctrs);
517
518 #ifdef DEBUG_GCDAPROFILING
519 fprintf(stderr, "llvmgcda: %u arcs\n", num_counters);
520 for (i = 0; i < num_counters; ++i)
521 fprintf(stderr, "llvmgcda: %llu\n", (unsigned long long)counters[i]);
522 #endif
523 }
524
525 COMPILER_RT_VISIBILITY
llvm_gcda_summary_info()526 void llvm_gcda_summary_info() {
527 uint32_t runs = 1;
528 static uint32_t run_counted = 0; // We only want to increase the run count once.
529 uint32_t val = 0;
530 uint64_t save_cur_pos = cur_pos;
531
532 if (!output_file) return;
533
534 val = read_32bit_value();
535
536 if (val != (uint32_t)-1) {
537 /* There are counters present in the file. Merge them. */
538 if (val != (gcov_version >= 90 ? GCOV_TAG_OBJECT_SUMMARY
539 : GCOV_TAG_PROGRAM_SUMMARY)) {
540 fprintf(stderr,
541 "profiling: %s: cannot merge previous run count: "
542 "corrupt object tag (0x%08x)\n",
543 filename, val);
544 return;
545 }
546
547 val = read_32bit_value(); /* length */
548 uint32_t prev_runs;
549 if (gcov_version < 90) {
550 read_32bit_value();
551 read_32bit_value();
552 prev_runs = read_32bit_value();
553 } else {
554 prev_runs = read_32bit_value();
555 read_32bit_value();
556 }
557 for (uint32_t i = gcov_version < 90 ? 3 : 2; i < val; ++i)
558 read_32bit_value();
559 /* Add previous run count to new counter, if not already counted before. */
560 runs = run_counted ? prev_runs : prev_runs + 1;
561 }
562
563 cur_pos = save_cur_pos;
564
565 if (gcov_version >= 90) {
566 write_32bit_value(GCOV_TAG_OBJECT_SUMMARY);
567 write_32bit_value(2);
568 write_32bit_value(runs);
569 write_32bit_value(0); // sum_max
570 } else {
571 // Before gcov 4.8 (r190952), GCOV_TAG_SUMMARY_LENGTH was 9. r190952 set
572 // GCOV_TAG_SUMMARY_LENGTH to 22. We simply use the smallest length which
573 // can make gcov read "Runs:".
574 write_32bit_value(GCOV_TAG_PROGRAM_SUMMARY);
575 write_32bit_value(3);
576 write_32bit_value(0);
577 write_32bit_value(0);
578 write_32bit_value(runs);
579 }
580
581 run_counted = 1;
582
583 #ifdef DEBUG_GCDAPROFILING
584 fprintf(stderr, "llvmgcda: %u runs\n", runs);
585 #endif
586 }
587
588 COMPILER_RT_VISIBILITY
llvm_gcda_end_file()589 void llvm_gcda_end_file() {
590 /* Write out EOF record. */
591 if (output_file) {
592 write_bytes("\0\0\0\0\0\0\0\0", 8);
593
594 if (new_file) {
595 fwrite(write_buffer, cur_pos, 1, output_file);
596 free(write_buffer);
597 } else {
598 unmap_file();
599 }
600
601 fflush(output_file);
602 lprofUnlockFd(fd);
603 fclose(output_file);
604 output_file = NULL;
605 write_buffer = NULL;
606 }
607 free(filename);
608
609 #ifdef DEBUG_GCDAPROFILING
610 fprintf(stderr, "llvmgcda: -----\n");
611 #endif
612 }
613
614 COMPILER_RT_VISIBILITY
llvm_register_writeout_function(fn_ptr fn)615 void llvm_register_writeout_function(fn_ptr fn) {
616 fn_list_insert(&writeout_fn_list, fn);
617 }
618
619 COMPILER_RT_VISIBILITY
llvm_writeout_files(void)620 void llvm_writeout_files(void) {
621 struct fn_node *curr = writeout_fn_list.head;
622
623 while (curr) {
624 if (curr->id == CURRENT_ID) {
625 curr->fn();
626 }
627 curr = curr->next;
628 }
629 }
630
631 #ifndef _WIN32
632 // __attribute__((destructor)) and destructors whose priorities are greater than
633 // 100 run before this function and can thus be tracked. The priority is
634 // compatible with GCC 7 onwards.
635 __attribute__((destructor(100)))
636 #endif
llvm_writeout_and_clear(void)637 static void llvm_writeout_and_clear(void) {
638 llvm_writeout_files();
639 fn_list_remove(&writeout_fn_list);
640 }
641
642 COMPILER_RT_VISIBILITY
llvm_register_flush_function(fn_ptr fn)643 void llvm_register_flush_function(fn_ptr fn) {
644 fn_list_insert(&flush_fn_list, fn);
645 }
646
__gcov_flush()647 void __gcov_flush() {
648 struct fn_node* curr = flush_fn_list.head;
649
650 while (curr) {
651 curr->fn();
652 curr = curr->next;
653 }
654 }
655
656 COMPILER_RT_VISIBILITY
llvm_delete_flush_function_list(void)657 void llvm_delete_flush_function_list(void) {
658 fn_list_remove(&flush_fn_list);
659 }
660
661 COMPILER_RT_VISIBILITY
llvm_register_reset_function(fn_ptr fn)662 void llvm_register_reset_function(fn_ptr fn) {
663 fn_list_insert(&reset_fn_list, fn);
664 }
665
666 COMPILER_RT_VISIBILITY
llvm_delete_reset_function_list(void)667 void llvm_delete_reset_function_list(void) { fn_list_remove(&reset_fn_list); }
668
669 COMPILER_RT_VISIBILITY
llvm_reset_counters(void)670 void llvm_reset_counters(void) {
671 struct fn_node *curr = reset_fn_list.head;
672
673 while (curr) {
674 if (curr->id == CURRENT_ID) {
675 curr->fn();
676 }
677 curr = curr->next;
678 }
679 }
680
681 #if !defined(_WIN32)
682 COMPILER_RT_VISIBILITY
__gcov_fork()683 pid_t __gcov_fork() {
684 pid_t parent_pid = getpid();
685 pid_t pid = fork();
686
687 if (pid == 0) {
688 pid_t child_pid = getpid();
689 if (child_pid != parent_pid) {
690 // The pid changed so we've a fork (one could have its own fork function)
691 // Just reset the counters for this child process
692 // threads.
693 llvm_reset_counters();
694 }
695 }
696 return pid;
697 }
698 #endif
699
700 COMPILER_RT_VISIBILITY
llvm_gcov_init(fn_ptr wfn,fn_ptr ffn,fn_ptr rfn)701 void llvm_gcov_init(fn_ptr wfn, fn_ptr ffn, fn_ptr rfn) {
702 static int atexit_ran = 0;
703
704 if (wfn)
705 llvm_register_writeout_function(wfn);
706
707 if (ffn)
708 llvm_register_flush_function(ffn);
709
710 if (rfn)
711 llvm_register_reset_function(rfn);
712
713 if (atexit_ran == 0) {
714 atexit_ran = 1;
715
716 /* Make sure we write out the data and delete the data structures. */
717 atexit(llvm_delete_reset_function_list);
718 atexit(llvm_delete_flush_function_list);
719 #ifdef _WIN32
720 atexit(llvm_writeout_and_clear);
721 #endif
722 }
723 }
724
725 #endif
726