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b92cccf4 1/* AddressSanitizer, a fast memory error detector.
fbd26352 2 Copyright (C) 2012-2019 Free Software Foundation, Inc.
b92cccf4 3 Contributed by Kostya Serebryany <kcc@google.com>
4
5This file is part of GCC.
6
7GCC is free software; you can redistribute it and/or modify it under
8the terms of the GNU General Public License as published by the Free
9Software Foundation; either version 3, or (at your option) any later
10version.
11
12GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13WARRANTY; without even the implied warranty of MERCHANTABILITY or
14FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15for 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
22#include "config.h"
23#include "system.h"
24#include "coretypes.h"
9ef16211 25#include "backend.h"
7c29e30e 26#include "target.h"
27#include "rtl.h"
41a8aa41 28#include "tree.h"
9ef16211 29#include "gimple.h"
7c29e30e 30#include "cfghooks.h"
31#include "alloc-pool.h"
32#include "tree-pass.h"
ad7b10a2 33#include "memmodel.h"
7c29e30e 34#include "tm_p.h"
c51887c5 35#include "ssa.h"
7c29e30e 36#include "stringpool.h"
37#include "tree-ssanames.h"
7c29e30e 38#include "optabs.h"
39#include "emit-rtl.h"
40#include "cgraph.h"
41#include "gimple-pretty-print.h"
42#include "alias.h"
b20a8bb4 43#include "fold-const.h"
94ea8568 44#include "cfganal.h"
a8783bee 45#include "gimplify.h"
dcf1a1ec 46#include "gimple-iterator.h"
9ed99284 47#include "varasm.h"
48#include "stor-layout.h"
b92cccf4 49#include "tree-iterator.h"
30a86690 50#include "stringpool.h"
51#include "attribs.h"
b92cccf4 52#include "asan.h"
d53441c8 53#include "dojump.h"
54#include "explow.h"
3c919612 55#include "expr.h"
92fc5c48 56#include "output.h"
b45e34ed 57#include "langhooks.h"
f6568ea4 58#include "cfgloop.h"
9a4a3348 59#include "gimple-builder.h"
d08919a7 60#include "gimple-fold.h"
19b928d9 61#include "ubsan.h"
bf2b7c22 62#include "params.h"
f7715905 63#include "builtins.h"
5cd86e48 64#include "fnmatch.h"
c51887c5 65#include "tree-inline.h"
b92cccf4 66
eca932e6 67/* AddressSanitizer finds out-of-bounds and use-after-free bugs
68 with <2x slowdown on average.
69
70 The tool consists of two parts:
71 instrumentation module (this file) and a run-time library.
72 The instrumentation module adds a run-time check before every memory insn.
73 For a 8- or 16- byte load accessing address X:
74 ShadowAddr = (X >> 3) + Offset
75 ShadowValue = *(char*)ShadowAddr; // *(short*) for 16-byte access.
76 if (ShadowValue)
77 __asan_report_load8(X);
78 For a load of N bytes (N=1, 2 or 4) from address X:
79 ShadowAddr = (X >> 3) + Offset
80 ShadowValue = *(char*)ShadowAddr;
81 if (ShadowValue)
82 if ((X & 7) + N - 1 > ShadowValue)
83 __asan_report_loadN(X);
84 Stores are instrumented similarly, but using __asan_report_storeN functions.
1e80ce41 85 A call too __asan_init_vN() is inserted to the list of module CTORs.
86 N is the version number of the AddressSanitizer API. The changes between the
87 API versions are listed in libsanitizer/asan/asan_interface_internal.h.
eca932e6 88
89 The run-time library redefines malloc (so that redzone are inserted around
90 the allocated memory) and free (so that reuse of free-ed memory is delayed),
1e80ce41 91 provides __asan_report* and __asan_init_vN functions.
eca932e6 92
93 Read more:
94 http://code.google.com/p/address-sanitizer/wiki/AddressSanitizerAlgorithm
95
96 The current implementation supports detection of out-of-bounds and
97 use-after-free in the heap, on the stack and for global variables.
98
99 [Protection of stack variables]
100
101 To understand how detection of out-of-bounds and use-after-free works
102 for stack variables, lets look at this example on x86_64 where the
103 stack grows downward:
3c919612 104
105 int
106 foo ()
107 {
108 char a[23] = {0};
109 int b[2] = {0};
110
111 a[5] = 1;
112 b[1] = 2;
113
114 return a[5] + b[1];
115 }
116
eca932e6 117 For this function, the stack protected by asan will be organized as
118 follows, from the top of the stack to the bottom:
3c919612 119
eca932e6 120 Slot 1/ [red zone of 32 bytes called 'RIGHT RedZone']
3c919612 121
eca932e6 122 Slot 2/ [8 bytes of red zone, that adds up to the space of 'a' to make
123 the next slot be 32 bytes aligned; this one is called Partial
124 Redzone; this 32 bytes alignment is an asan constraint]
3c919612 125
eca932e6 126 Slot 3/ [24 bytes for variable 'a']
3c919612 127
eca932e6 128 Slot 4/ [red zone of 32 bytes called 'Middle RedZone']
3c919612 129
eca932e6 130 Slot 5/ [24 bytes of Partial Red Zone (similar to slot 2]
3c919612 131
eca932e6 132 Slot 6/ [8 bytes for variable 'b']
3c919612 133
eca932e6 134 Slot 7/ [32 bytes of Red Zone at the bottom of the stack, called
135 'LEFT RedZone']
3c919612 136
eca932e6 137 The 32 bytes of LEFT red zone at the bottom of the stack can be
138 decomposed as such:
3c919612 139
140 1/ The first 8 bytes contain a magical asan number that is always
141 0x41B58AB3.
142
143 2/ The following 8 bytes contains a pointer to a string (to be
144 parsed at runtime by the runtime asan library), which format is
145 the following:
146
147 "<function-name> <space> <num-of-variables-on-the-stack>
148 (<32-bytes-aligned-offset-in-bytes-of-variable> <space>
149 <length-of-var-in-bytes> ){n} "
150
151 where '(...){n}' means the content inside the parenthesis occurs 'n'
152 times, with 'n' being the number of variables on the stack.
e815c2c5 153
1e80ce41 154 3/ The following 8 bytes contain the PC of the current function which
155 will be used by the run-time library to print an error message.
3c919612 156
1e80ce41 157 4/ The following 8 bytes are reserved for internal use by the run-time.
3c919612 158
eca932e6 159 The shadow memory for that stack layout is going to look like this:
3c919612 160
161 - content of shadow memory 8 bytes for slot 7: 0xF1F1F1F1.
162 The F1 byte pattern is a magic number called
163 ASAN_STACK_MAGIC_LEFT and is a way for the runtime to know that
164 the memory for that shadow byte is part of a the LEFT red zone
165 intended to seat at the bottom of the variables on the stack.
166
167 - content of shadow memory 8 bytes for slots 6 and 5:
168 0xF4F4F400. The F4 byte pattern is a magic number
169 called ASAN_STACK_MAGIC_PARTIAL. It flags the fact that the
170 memory region for this shadow byte is a PARTIAL red zone
171 intended to pad a variable A, so that the slot following
172 {A,padding} is 32 bytes aligned.
173
174 Note that the fact that the least significant byte of this
175 shadow memory content is 00 means that 8 bytes of its
176 corresponding memory (which corresponds to the memory of
177 variable 'b') is addressable.
178
179 - content of shadow memory 8 bytes for slot 4: 0xF2F2F2F2.
180 The F2 byte pattern is a magic number called
181 ASAN_STACK_MAGIC_MIDDLE. It flags the fact that the memory
182 region for this shadow byte is a MIDDLE red zone intended to
183 seat between two 32 aligned slots of {variable,padding}.
184
185 - content of shadow memory 8 bytes for slot 3 and 2:
eca932e6 186 0xF4000000. This represents is the concatenation of
3c919612 187 variable 'a' and the partial red zone following it, like what we
188 had for variable 'b'. The least significant 3 bytes being 00
189 means that the 3 bytes of variable 'a' are addressable.
190
eca932e6 191 - content of shadow memory 8 bytes for slot 1: 0xF3F3F3F3.
3c919612 192 The F3 byte pattern is a magic number called
193 ASAN_STACK_MAGIC_RIGHT. It flags the fact that the memory
194 region for this shadow byte is a RIGHT red zone intended to seat
195 at the top of the variables of the stack.
196
eca932e6 197 Note that the real variable layout is done in expand_used_vars in
198 cfgexpand.c. As far as Address Sanitizer is concerned, it lays out
199 stack variables as well as the different red zones, emits some
200 prologue code to populate the shadow memory as to poison (mark as
201 non-accessible) the regions of the red zones and mark the regions of
202 stack variables as accessible, and emit some epilogue code to
203 un-poison (mark as accessible) the regions of red zones right before
204 the function exits.
92fc5c48 205
eca932e6 206 [Protection of global variables]
92fc5c48 207
eca932e6 208 The basic idea is to insert a red zone between two global variables
209 and install a constructor function that calls the asan runtime to do
210 the populating of the relevant shadow memory regions at load time.
92fc5c48 211
eca932e6 212 So the global variables are laid out as to insert a red zone between
213 them. The size of the red zones is so that each variable starts on a
214 32 bytes boundary.
92fc5c48 215
eca932e6 216 Then a constructor function is installed so that, for each global
217 variable, it calls the runtime asan library function
218 __asan_register_globals_with an instance of this type:
92fc5c48 219
220 struct __asan_global
221 {
222 // Address of the beginning of the global variable.
223 const void *__beg;
224
225 // Initial size of the global variable.
226 uptr __size;
227
228 // Size of the global variable + size of the red zone. This
229 // size is 32 bytes aligned.
230 uptr __size_with_redzone;
231
232 // Name of the global variable.
233 const void *__name;
234
1e80ce41 235 // Name of the module where the global variable is declared.
236 const void *__module_name;
237
085f6ebf 238 // 1 if it has dynamic initialization, 0 otherwise.
92fc5c48 239 uptr __has_dynamic_init;
a9586c9c 240
241 // A pointer to struct that contains source location, could be NULL.
242 __asan_global_source_location *__location;
92fc5c48 243 }
244
eca932e6 245 A destructor function that calls the runtime asan library function
246 _asan_unregister_globals is also installed. */
3c919612 247
cf357977 248static unsigned HOST_WIDE_INT asan_shadow_offset_value;
249static bool asan_shadow_offset_computed;
5cd86e48 250static vec<char *> sanitized_sections;
d08919a7 251static tree last_alloca_addr;
cf357977 252
629b6abc 253/* Set of variable declarations that are going to be guarded by
254 use-after-scope sanitizer. */
255
4f28881f 256hash_set<tree> *asan_handled_variables = NULL;
629b6abc 257
258hash_set <tree> *asan_used_labels = NULL;
259
cf357977 260/* Sets shadow offset to value in string VAL. */
261
262bool
263set_asan_shadow_offset (const char *val)
264{
265 char *endp;
e815c2c5 266
cf357977 267 errno = 0;
268#ifdef HAVE_LONG_LONG
269 asan_shadow_offset_value = strtoull (val, &endp, 0);
270#else
271 asan_shadow_offset_value = strtoul (val, &endp, 0);
272#endif
273 if (!(*val != '\0' && *endp == '\0' && errno == 0))
274 return false;
275
276 asan_shadow_offset_computed = true;
277
278 return true;
279}
280
4d3c996b 281/* Set list of user-defined sections that need to be sanitized. */
282
283void
5cd86e48 284set_sanitized_sections (const char *sections)
4d3c996b 285{
5cd86e48 286 char *pat;
287 unsigned i;
288 FOR_EACH_VEC_ELT (sanitized_sections, i, pat)
289 free (pat);
290 sanitized_sections.truncate (0);
291
292 for (const char *s = sections; *s; )
293 {
294 const char *end;
295 for (end = s; *end && *end != ','; ++end);
296 size_t len = end - s;
297 sanitized_sections.safe_push (xstrndup (s, len));
298 s = *end ? end + 1 : end;
299 }
4d3c996b 300}
301
a30589d5 302bool
303asan_mark_p (gimple *stmt, enum asan_mark_flags flag)
304{
305 return (gimple_call_internal_p (stmt, IFN_ASAN_MARK)
306 && tree_to_uhwi (gimple_call_arg (stmt, 0)) == flag);
307}
308
629b6abc 309bool
310asan_sanitize_stack_p (void)
311{
9917317a 312 return (sanitize_flags_p (SANITIZE_ADDRESS) && ASAN_STACK);
629b6abc 313}
314
77c44489 315bool
316asan_sanitize_allocas_p (void)
317{
318 return (asan_sanitize_stack_p () && ASAN_PROTECT_ALLOCAS);
319}
320
4d3c996b 321/* Checks whether section SEC should be sanitized. */
322
323static bool
324section_sanitized_p (const char *sec)
325{
5cd86e48 326 char *pat;
327 unsigned i;
328 FOR_EACH_VEC_ELT (sanitized_sections, i, pat)
329 if (fnmatch (pat, sec, FNM_PERIOD) == 0)
330 return true;
4d3c996b 331 return false;
332}
333
cf357977 334/* Returns Asan shadow offset. */
335
336static unsigned HOST_WIDE_INT
337asan_shadow_offset ()
338{
339 if (!asan_shadow_offset_computed)
340 {
341 asan_shadow_offset_computed = true;
342 asan_shadow_offset_value = targetm.asan_shadow_offset ();
343 }
344 return asan_shadow_offset_value;
345}
346
3c919612 347alias_set_type asan_shadow_set = -1;
b92cccf4 348
629b6abc 349/* Pointer types to 1, 2 or 4 byte integers in shadow memory. A separate
5d5c682b 350 alias set is used for all shadow memory accesses. */
629b6abc 351static GTY(()) tree shadow_ptr_types[3];
5d5c682b 352
683539f6 353/* Decl for __asan_option_detect_stack_use_after_return. */
354static GTY(()) tree asan_detect_stack_use_after_return;
355
c31c80df 356/* Hashtable support for memory references used by gimple
357 statements. */
358
359/* This type represents a reference to a memory region. */
360struct asan_mem_ref
361{
a04e8d62 362 /* The expression of the beginning of the memory region. */
c31c80df 363 tree start;
364
86d3a572 365 /* The size of the access. */
366 HOST_WIDE_INT access_size;
e815c2c5 367};
368
1dc6c44d 369object_allocator <asan_mem_ref> asan_mem_ref_pool ("asan_mem_ref");
c31c80df 370
371/* Initializes an instance of asan_mem_ref. */
372
373static void
86d3a572 374asan_mem_ref_init (asan_mem_ref *ref, tree start, HOST_WIDE_INT access_size)
c31c80df 375{
376 ref->start = start;
377 ref->access_size = access_size;
378}
379
380/* Allocates memory for an instance of asan_mem_ref into the memory
381 pool returned by asan_mem_ref_get_alloc_pool and initialize it.
382 START is the address of (or the expression pointing to) the
383 beginning of memory reference. ACCESS_SIZE is the size of the
384 access to the referenced memory. */
385
386static asan_mem_ref*
86d3a572 387asan_mem_ref_new (tree start, HOST_WIDE_INT access_size)
c31c80df 388{
e16712b1 389 asan_mem_ref *ref = asan_mem_ref_pool.allocate ();
c31c80df 390
391 asan_mem_ref_init (ref, start, access_size);
392 return ref;
393}
394
395/* This builds and returns a pointer to the end of the memory region
396 that starts at START and of length LEN. */
397
398tree
399asan_mem_ref_get_end (tree start, tree len)
400{
401 if (len == NULL_TREE || integer_zerop (len))
402 return start;
403
0a9f72cf 404 if (!ptrofftype_p (len))
405 len = convert_to_ptrofftype (len);
406
c31c80df 407 return fold_build2 (POINTER_PLUS_EXPR, TREE_TYPE (start), start, len);
408}
409
410/* Return a tree expression that represents the end of the referenced
411 memory region. Beware that this function can actually build a new
412 tree expression. */
413
414tree
415asan_mem_ref_get_end (const asan_mem_ref *ref, tree len)
416{
417 return asan_mem_ref_get_end (ref->start, len);
418}
419
770ff93b 420struct asan_mem_ref_hasher : nofree_ptr_hash <asan_mem_ref>
c31c80df 421{
9969c043 422 static inline hashval_t hash (const asan_mem_ref *);
423 static inline bool equal (const asan_mem_ref *, const asan_mem_ref *);
c31c80df 424};
425
426/* Hash a memory reference. */
427
428inline hashval_t
429asan_mem_ref_hasher::hash (const asan_mem_ref *mem_ref)
430{
f9acf11a 431 return iterative_hash_expr (mem_ref->start, 0);
c31c80df 432}
433
434/* Compare two memory references. We accept the length of either
435 memory references to be NULL_TREE. */
436
437inline bool
438asan_mem_ref_hasher::equal (const asan_mem_ref *m1,
439 const asan_mem_ref *m2)
440{
f9acf11a 441 return operand_equal_p (m1->start, m2->start, 0);
c31c80df 442}
443
c1f445d2 444static hash_table<asan_mem_ref_hasher> *asan_mem_ref_ht;
c31c80df 445
446/* Returns a reference to the hash table containing memory references.
447 This function ensures that the hash table is created. Note that
448 this hash table is updated by the function
449 update_mem_ref_hash_table. */
450
c1f445d2 451static hash_table<asan_mem_ref_hasher> *
c31c80df 452get_mem_ref_hash_table ()
453{
c1f445d2 454 if (!asan_mem_ref_ht)
455 asan_mem_ref_ht = new hash_table<asan_mem_ref_hasher> (10);
c31c80df 456
457 return asan_mem_ref_ht;
458}
459
460/* Clear all entries from the memory references hash table. */
461
462static void
463empty_mem_ref_hash_table ()
464{
c1f445d2 465 if (asan_mem_ref_ht)
466 asan_mem_ref_ht->empty ();
c31c80df 467}
468
469/* Free the memory references hash table. */
470
471static void
472free_mem_ref_resources ()
473{
c1f445d2 474 delete asan_mem_ref_ht;
475 asan_mem_ref_ht = NULL;
c31c80df 476
e16712b1 477 asan_mem_ref_pool.release ();
c31c80df 478}
479
480/* Return true iff the memory reference REF has been instrumented. */
481
482static bool
86d3a572 483has_mem_ref_been_instrumented (tree ref, HOST_WIDE_INT access_size)
c31c80df 484{
485 asan_mem_ref r;
486 asan_mem_ref_init (&r, ref, access_size);
487
f9acf11a 488 asan_mem_ref *saved_ref = get_mem_ref_hash_table ()->find (&r);
489 return saved_ref && saved_ref->access_size >= access_size;
c31c80df 490}
491
492/* Return true iff the memory reference REF has been instrumented. */
493
494static bool
495has_mem_ref_been_instrumented (const asan_mem_ref *ref)
496{
497 return has_mem_ref_been_instrumented (ref->start, ref->access_size);
498}
499
500/* Return true iff access to memory region starting at REF and of
501 length LEN has been instrumented. */
502
503static bool
504has_mem_ref_been_instrumented (const asan_mem_ref *ref, tree len)
505{
f9acf11a 506 HOST_WIDE_INT size_in_bytes
507 = tree_fits_shwi_p (len) ? tree_to_shwi (len) : -1;
c31c80df 508
f9acf11a 509 return size_in_bytes != -1
510 && has_mem_ref_been_instrumented (ref->start, size_in_bytes);
c31c80df 511}
512
513/* Set REF to the memory reference present in a gimple assignment
514 ASSIGNMENT. Return true upon successful completion, false
515 otherwise. */
516
517static bool
1a91d914 518get_mem_ref_of_assignment (const gassign *assignment,
c31c80df 519 asan_mem_ref *ref,
520 bool *ref_is_store)
521{
522 gcc_assert (gimple_assign_single_p (assignment));
523
9f559b20 524 if (gimple_store_p (assignment)
525 && !gimple_clobber_p (assignment))
c31c80df 526 {
527 ref->start = gimple_assign_lhs (assignment);
528 *ref_is_store = true;
529 }
530 else if (gimple_assign_load_p (assignment))
531 {
532 ref->start = gimple_assign_rhs1 (assignment);
533 *ref_is_store = false;
534 }
535 else
536 return false;
537
538 ref->access_size = int_size_in_bytes (TREE_TYPE (ref->start));
539 return true;
540}
541
d08919a7 542/* Return address of last allocated dynamic alloca. */
543
544static tree
545get_last_alloca_addr ()
546{
547 if (last_alloca_addr)
548 return last_alloca_addr;
549
550 last_alloca_addr = create_tmp_reg (ptr_type_node, "last_alloca_addr");
551 gassign *g = gimple_build_assign (last_alloca_addr, null_pointer_node);
552 edge e = single_succ_edge (ENTRY_BLOCK_PTR_FOR_FN (cfun));
553 gsi_insert_on_edge_immediate (e, g);
554 return last_alloca_addr;
555}
556
829e6a9b 557/* Insert __asan_allocas_unpoison (top, bottom) call before
d08919a7 558 __builtin_stack_restore (new_sp) call.
559 The pseudocode of this routine should look like this:
d08919a7 560 top = last_alloca_addr;
561 bot = new_sp;
562 __asan_allocas_unpoison (top, bot);
563 last_alloca_addr = new_sp;
829e6a9b 564 __builtin_stack_restore (new_sp);
d08919a7 565 In general, we can't use new_sp as bot parameter because on some
566 architectures SP has non zero offset from dynamic stack area. Moreover, on
567 some architectures this offset (STACK_DYNAMIC_OFFSET) becomes known for each
568 particular function only after all callees were expanded to rtl.
569 The most noticeable example is PowerPC{,64}, see
570 http://refspecs.linuxfoundation.org/ELF/ppc64/PPC-elf64abi.html#DYNAM-STACK.
571 To overcome the issue we use following trick: pass new_sp as a second
572 parameter to __asan_allocas_unpoison and rewrite it during expansion with
829e6a9b 573 new_sp + (virtual_dynamic_stack_rtx - sp) later in
574 expand_asan_emit_allocas_unpoison function. */
d08919a7 575
576static void
577handle_builtin_stack_restore (gcall *call, gimple_stmt_iterator *iter)
578{
77c44489 579 if (!iter || !asan_sanitize_allocas_p ())
d08919a7 580 return;
581
582 tree last_alloca = get_last_alloca_addr ();
583 tree restored_stack = gimple_call_arg (call, 0);
584 tree fn = builtin_decl_implicit (BUILT_IN_ASAN_ALLOCAS_UNPOISON);
585 gimple *g = gimple_build_call (fn, 2, last_alloca, restored_stack);
829e6a9b 586 gsi_insert_before (iter, g, GSI_SAME_STMT);
d08919a7 587 g = gimple_build_assign (last_alloca, restored_stack);
829e6a9b 588 gsi_insert_before (iter, g, GSI_SAME_STMT);
d08919a7 589}
590
591/* Deploy and poison redzones around __builtin_alloca call. To do this, we
592 should replace this call with another one with changed parameters and
593 replace all its uses with new address, so
594 addr = __builtin_alloca (old_size, align);
595 is replaced by
596 left_redzone_size = max (align, ASAN_RED_ZONE_SIZE);
597 Following two statements are optimized out if we know that
598 old_size & (ASAN_RED_ZONE_SIZE - 1) == 0, i.e. alloca doesn't need partial
599 redzone.
600 misalign = old_size & (ASAN_RED_ZONE_SIZE - 1);
601 partial_redzone_size = ASAN_RED_ZONE_SIZE - misalign;
602 right_redzone_size = ASAN_RED_ZONE_SIZE;
603 additional_size = left_redzone_size + partial_redzone_size +
604 right_redzone_size;
605 new_size = old_size + additional_size;
606 new_alloca = __builtin_alloca (new_size, max (align, 32))
607 __asan_alloca_poison (new_alloca, old_size)
608 addr = new_alloca + max (align, ASAN_RED_ZONE_SIZE);
609 last_alloca_addr = new_alloca;
610 ADDITIONAL_SIZE is added to make new memory allocation contain not only
611 requested memory, but also left, partial and right redzones as well as some
612 additional space, required by alignment. */
613
614static void
615handle_builtin_alloca (gcall *call, gimple_stmt_iterator *iter)
616{
77c44489 617 if (!iter || !asan_sanitize_allocas_p ())
d08919a7 618 return;
619
620 gassign *g;
621 gcall *gg;
622 const HOST_WIDE_INT redzone_mask = ASAN_RED_ZONE_SIZE - 1;
623
624 tree last_alloca = get_last_alloca_addr ();
625 tree callee = gimple_call_fndecl (call);
626 tree old_size = gimple_call_arg (call, 0);
627 tree ptr_type = gimple_call_lhs (call) ? TREE_TYPE (gimple_call_lhs (call))
628 : ptr_type_node;
629 tree partial_size = NULL_TREE;
d08919a7 630 unsigned int align
2b34677f 631 = DECL_FUNCTION_CODE (callee) == BUILT_IN_ALLOCA
632 ? 0 : tree_to_uhwi (gimple_call_arg (call, 1));
d08919a7 633
634 /* If ALIGN > ASAN_RED_ZONE_SIZE, we embed left redzone into first ALIGN
635 bytes of allocated space. Otherwise, align alloca to ASAN_RED_ZONE_SIZE
636 manually. */
637 align = MAX (align, ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
638
639 tree alloca_rz_mask = build_int_cst (size_type_node, redzone_mask);
640 tree redzone_size = build_int_cst (size_type_node, ASAN_RED_ZONE_SIZE);
641
642 /* Extract lower bits from old_size. */
643 wide_int size_nonzero_bits = get_nonzero_bits (old_size);
644 wide_int rz_mask
645 = wi::uhwi (redzone_mask, wi::get_precision (size_nonzero_bits));
646 wide_int old_size_lower_bits = wi::bit_and (size_nonzero_bits, rz_mask);
647
648 /* If alloca size is aligned to ASAN_RED_ZONE_SIZE, we don't need partial
649 redzone. Otherwise, compute its size here. */
650 if (wi::ne_p (old_size_lower_bits, 0))
651 {
652 /* misalign = size & (ASAN_RED_ZONE_SIZE - 1)
653 partial_size = ASAN_RED_ZONE_SIZE - misalign. */
654 g = gimple_build_assign (make_ssa_name (size_type_node, NULL),
655 BIT_AND_EXPR, old_size, alloca_rz_mask);
656 gsi_insert_before (iter, g, GSI_SAME_STMT);
657 tree misalign = gimple_assign_lhs (g);
658 g = gimple_build_assign (make_ssa_name (size_type_node, NULL), MINUS_EXPR,
659 redzone_size, misalign);
660 gsi_insert_before (iter, g, GSI_SAME_STMT);
661 partial_size = gimple_assign_lhs (g);
662 }
663
664 /* additional_size = align + ASAN_RED_ZONE_SIZE. */
665 tree additional_size = build_int_cst (size_type_node, align / BITS_PER_UNIT
666 + ASAN_RED_ZONE_SIZE);
667 /* If alloca has partial redzone, include it to additional_size too. */
668 if (partial_size)
669 {
670 /* additional_size += partial_size. */
671 g = gimple_build_assign (make_ssa_name (size_type_node), PLUS_EXPR,
672 partial_size, additional_size);
673 gsi_insert_before (iter, g, GSI_SAME_STMT);
674 additional_size = gimple_assign_lhs (g);
675 }
676
677 /* new_size = old_size + additional_size. */
678 g = gimple_build_assign (make_ssa_name (size_type_node), PLUS_EXPR, old_size,
679 additional_size);
680 gsi_insert_before (iter, g, GSI_SAME_STMT);
681 tree new_size = gimple_assign_lhs (g);
682
683 /* Build new __builtin_alloca call:
684 new_alloca_with_rz = __builtin_alloca (new_size, align). */
685 tree fn = builtin_decl_implicit (BUILT_IN_ALLOCA_WITH_ALIGN);
686 gg = gimple_build_call (fn, 2, new_size,
687 build_int_cst (size_type_node, align));
688 tree new_alloca_with_rz = make_ssa_name (ptr_type, gg);
689 gimple_call_set_lhs (gg, new_alloca_with_rz);
690 gsi_insert_before (iter, gg, GSI_SAME_STMT);
691
692 /* new_alloca = new_alloca_with_rz + align. */
693 g = gimple_build_assign (make_ssa_name (ptr_type), POINTER_PLUS_EXPR,
694 new_alloca_with_rz,
695 build_int_cst (size_type_node,
696 align / BITS_PER_UNIT));
697 gsi_insert_before (iter, g, GSI_SAME_STMT);
698 tree new_alloca = gimple_assign_lhs (g);
699
700 /* Poison newly created alloca redzones:
701 __asan_alloca_poison (new_alloca, old_size). */
702 fn = builtin_decl_implicit (BUILT_IN_ASAN_ALLOCA_POISON);
703 gg = gimple_build_call (fn, 2, new_alloca, old_size);
704 gsi_insert_before (iter, gg, GSI_SAME_STMT);
705
706 /* Save new_alloca_with_rz value into last_alloca to use it during
707 allocas unpoisoning. */
708 g = gimple_build_assign (last_alloca, new_alloca_with_rz);
709 gsi_insert_before (iter, g, GSI_SAME_STMT);
710
711 /* Finally, replace old alloca ptr with NEW_ALLOCA. */
712 replace_call_with_value (iter, new_alloca);
713}
714
c31c80df 715/* Return the memory references contained in a gimple statement
716 representing a builtin call that has to do with memory access. */
717
718static bool
d08919a7 719get_mem_refs_of_builtin_call (gcall *call,
c31c80df 720 asan_mem_ref *src0,
721 tree *src0_len,
722 bool *src0_is_store,
723 asan_mem_ref *src1,
724 tree *src1_len,
725 bool *src1_is_store,
726 asan_mem_ref *dst,
727 tree *dst_len,
728 bool *dst_is_store,
f9acf11a 729 bool *dest_is_deref,
d08919a7 730 bool *intercepted_p,
731 gimple_stmt_iterator *iter = NULL)
c31c80df 732{
733 gcc_checking_assert (gimple_call_builtin_p (call, BUILT_IN_NORMAL));
734
735 tree callee = gimple_call_fndecl (call);
736 tree source0 = NULL_TREE, source1 = NULL_TREE,
737 dest = NULL_TREE, len = NULL_TREE;
738 bool is_store = true, got_reference_p = false;
86d3a572 739 HOST_WIDE_INT access_size = 1;
c31c80df 740
f9acf11a 741 *intercepted_p = asan_intercepted_p ((DECL_FUNCTION_CODE (callee)));
742
c31c80df 743 switch (DECL_FUNCTION_CODE (callee))
744 {
745 /* (s, s, n) style memops. */
746 case BUILT_IN_BCMP:
747 case BUILT_IN_MEMCMP:
748 source0 = gimple_call_arg (call, 0);
749 source1 = gimple_call_arg (call, 1);
750 len = gimple_call_arg (call, 2);
751 break;
752
753 /* (src, dest, n) style memops. */
754 case BUILT_IN_BCOPY:
755 source0 = gimple_call_arg (call, 0);
756 dest = gimple_call_arg (call, 1);
757 len = gimple_call_arg (call, 2);
758 break;
759
760 /* (dest, src, n) style memops. */
761 case BUILT_IN_MEMCPY:
762 case BUILT_IN_MEMCPY_CHK:
763 case BUILT_IN_MEMMOVE:
764 case BUILT_IN_MEMMOVE_CHK:
765 case BUILT_IN_MEMPCPY:
766 case BUILT_IN_MEMPCPY_CHK:
767 dest = gimple_call_arg (call, 0);
768 source0 = gimple_call_arg (call, 1);
769 len = gimple_call_arg (call, 2);
770 break;
771
772 /* (dest, n) style memops. */
773 case BUILT_IN_BZERO:
774 dest = gimple_call_arg (call, 0);
775 len = gimple_call_arg (call, 1);
776 break;
777
778 /* (dest, x, n) style memops*/
779 case BUILT_IN_MEMSET:
780 case BUILT_IN_MEMSET_CHK:
781 dest = gimple_call_arg (call, 0);
782 len = gimple_call_arg (call, 2);
783 break;
784
785 case BUILT_IN_STRLEN:
786 source0 = gimple_call_arg (call, 0);
787 len = gimple_call_lhs (call);
6e48ee8f 788 break;
c31c80df 789
d08919a7 790 case BUILT_IN_STACK_RESTORE:
791 handle_builtin_stack_restore (call, iter);
792 break;
793
2b34677f 794 CASE_BUILT_IN_ALLOCA:
d08919a7 795 handle_builtin_alloca (call, iter);
796 break;
c31c80df 797 /* And now the __atomic* and __sync builtins.
798 These are handled differently from the classical memory memory
799 access builtins above. */
800
801 case BUILT_IN_ATOMIC_LOAD_1:
c31c80df 802 is_store = false;
6e48ee8f 803 /* FALLTHRU */
c31c80df 804 case BUILT_IN_SYNC_FETCH_AND_ADD_1:
c31c80df 805 case BUILT_IN_SYNC_FETCH_AND_SUB_1:
c31c80df 806 case BUILT_IN_SYNC_FETCH_AND_OR_1:
c31c80df 807 case BUILT_IN_SYNC_FETCH_AND_AND_1:
c31c80df 808 case BUILT_IN_SYNC_FETCH_AND_XOR_1:
c31c80df 809 case BUILT_IN_SYNC_FETCH_AND_NAND_1:
c31c80df 810 case BUILT_IN_SYNC_ADD_AND_FETCH_1:
c31c80df 811 case BUILT_IN_SYNC_SUB_AND_FETCH_1:
c31c80df 812 case BUILT_IN_SYNC_OR_AND_FETCH_1:
c31c80df 813 case BUILT_IN_SYNC_AND_AND_FETCH_1:
c31c80df 814 case BUILT_IN_SYNC_XOR_AND_FETCH_1:
c31c80df 815 case BUILT_IN_SYNC_NAND_AND_FETCH_1:
c31c80df 816 case BUILT_IN_SYNC_BOOL_COMPARE_AND_SWAP_1:
c31c80df 817 case BUILT_IN_SYNC_VAL_COMPARE_AND_SWAP_1:
c31c80df 818 case BUILT_IN_SYNC_LOCK_TEST_AND_SET_1:
c31c80df 819 case BUILT_IN_SYNC_LOCK_RELEASE_1:
c31c80df 820 case BUILT_IN_ATOMIC_EXCHANGE_1:
c31c80df 821 case BUILT_IN_ATOMIC_COMPARE_EXCHANGE_1:
c31c80df 822 case BUILT_IN_ATOMIC_STORE_1:
c31c80df 823 case BUILT_IN_ATOMIC_ADD_FETCH_1:
c31c80df 824 case BUILT_IN_ATOMIC_SUB_FETCH_1:
c31c80df 825 case BUILT_IN_ATOMIC_AND_FETCH_1:
c31c80df 826 case BUILT_IN_ATOMIC_NAND_FETCH_1:
c31c80df 827 case BUILT_IN_ATOMIC_XOR_FETCH_1:
c31c80df 828 case BUILT_IN_ATOMIC_OR_FETCH_1:
c31c80df 829 case BUILT_IN_ATOMIC_FETCH_ADD_1:
c31c80df 830 case BUILT_IN_ATOMIC_FETCH_SUB_1:
c31c80df 831 case BUILT_IN_ATOMIC_FETCH_AND_1:
c31c80df 832 case BUILT_IN_ATOMIC_FETCH_NAND_1:
c31c80df 833 case BUILT_IN_ATOMIC_FETCH_XOR_1:
c31c80df 834 case BUILT_IN_ATOMIC_FETCH_OR_1:
6e48ee8f 835 access_size = 1;
836 goto do_atomic;
837
838 case BUILT_IN_ATOMIC_LOAD_2:
839 is_store = false;
840 /* FALLTHRU */
841 case BUILT_IN_SYNC_FETCH_AND_ADD_2:
842 case BUILT_IN_SYNC_FETCH_AND_SUB_2:
843 case BUILT_IN_SYNC_FETCH_AND_OR_2:
844 case BUILT_IN_SYNC_FETCH_AND_AND_2:
845 case BUILT_IN_SYNC_FETCH_AND_XOR_2:
846 case BUILT_IN_SYNC_FETCH_AND_NAND_2:
847 case BUILT_IN_SYNC_ADD_AND_FETCH_2:
848 case BUILT_IN_SYNC_SUB_AND_FETCH_2:
849 case BUILT_IN_SYNC_OR_AND_FETCH_2:
850 case BUILT_IN_SYNC_AND_AND_FETCH_2:
851 case BUILT_IN_SYNC_XOR_AND_FETCH_2:
852 case BUILT_IN_SYNC_NAND_AND_FETCH_2:
853 case BUILT_IN_SYNC_BOOL_COMPARE_AND_SWAP_2:
854 case BUILT_IN_SYNC_VAL_COMPARE_AND_SWAP_2:
855 case BUILT_IN_SYNC_LOCK_TEST_AND_SET_2:
856 case BUILT_IN_SYNC_LOCK_RELEASE_2:
857 case BUILT_IN_ATOMIC_EXCHANGE_2:
858 case BUILT_IN_ATOMIC_COMPARE_EXCHANGE_2:
859 case BUILT_IN_ATOMIC_STORE_2:
860 case BUILT_IN_ATOMIC_ADD_FETCH_2:
861 case BUILT_IN_ATOMIC_SUB_FETCH_2:
862 case BUILT_IN_ATOMIC_AND_FETCH_2:
863 case BUILT_IN_ATOMIC_NAND_FETCH_2:
864 case BUILT_IN_ATOMIC_XOR_FETCH_2:
865 case BUILT_IN_ATOMIC_OR_FETCH_2:
866 case BUILT_IN_ATOMIC_FETCH_ADD_2:
867 case BUILT_IN_ATOMIC_FETCH_SUB_2:
868 case BUILT_IN_ATOMIC_FETCH_AND_2:
869 case BUILT_IN_ATOMIC_FETCH_NAND_2:
870 case BUILT_IN_ATOMIC_FETCH_XOR_2:
c31c80df 871 case BUILT_IN_ATOMIC_FETCH_OR_2:
6e48ee8f 872 access_size = 2;
873 goto do_atomic;
874
875 case BUILT_IN_ATOMIC_LOAD_4:
876 is_store = false;
877 /* FALLTHRU */
878 case BUILT_IN_SYNC_FETCH_AND_ADD_4:
879 case BUILT_IN_SYNC_FETCH_AND_SUB_4:
880 case BUILT_IN_SYNC_FETCH_AND_OR_4:
881 case BUILT_IN_SYNC_FETCH_AND_AND_4:
882 case BUILT_IN_SYNC_FETCH_AND_XOR_4:
883 case BUILT_IN_SYNC_FETCH_AND_NAND_4:
884 case BUILT_IN_SYNC_ADD_AND_FETCH_4:
885 case BUILT_IN_SYNC_SUB_AND_FETCH_4:
886 case BUILT_IN_SYNC_OR_AND_FETCH_4:
887 case BUILT_IN_SYNC_AND_AND_FETCH_4:
888 case BUILT_IN_SYNC_XOR_AND_FETCH_4:
889 case BUILT_IN_SYNC_NAND_AND_FETCH_4:
890 case BUILT_IN_SYNC_BOOL_COMPARE_AND_SWAP_4:
891 case BUILT_IN_SYNC_VAL_COMPARE_AND_SWAP_4:
892 case BUILT_IN_SYNC_LOCK_TEST_AND_SET_4:
893 case BUILT_IN_SYNC_LOCK_RELEASE_4:
894 case BUILT_IN_ATOMIC_EXCHANGE_4:
895 case BUILT_IN_ATOMIC_COMPARE_EXCHANGE_4:
896 case BUILT_IN_ATOMIC_STORE_4:
897 case BUILT_IN_ATOMIC_ADD_FETCH_4:
898 case BUILT_IN_ATOMIC_SUB_FETCH_4:
899 case BUILT_IN_ATOMIC_AND_FETCH_4:
900 case BUILT_IN_ATOMIC_NAND_FETCH_4:
901 case BUILT_IN_ATOMIC_XOR_FETCH_4:
902 case BUILT_IN_ATOMIC_OR_FETCH_4:
903 case BUILT_IN_ATOMIC_FETCH_ADD_4:
904 case BUILT_IN_ATOMIC_FETCH_SUB_4:
905 case BUILT_IN_ATOMIC_FETCH_AND_4:
906 case BUILT_IN_ATOMIC_FETCH_NAND_4:
907 case BUILT_IN_ATOMIC_FETCH_XOR_4:
c31c80df 908 case BUILT_IN_ATOMIC_FETCH_OR_4:
6e48ee8f 909 access_size = 4;
910 goto do_atomic;
911
912 case BUILT_IN_ATOMIC_LOAD_8:
913 is_store = false;
914 /* FALLTHRU */
915 case BUILT_IN_SYNC_FETCH_AND_ADD_8:
916 case BUILT_IN_SYNC_FETCH_AND_SUB_8:
917 case BUILT_IN_SYNC_FETCH_AND_OR_8:
918 case BUILT_IN_SYNC_FETCH_AND_AND_8:
919 case BUILT_IN_SYNC_FETCH_AND_XOR_8:
920 case BUILT_IN_SYNC_FETCH_AND_NAND_8:
921 case BUILT_IN_SYNC_ADD_AND_FETCH_8:
922 case BUILT_IN_SYNC_SUB_AND_FETCH_8:
923 case BUILT_IN_SYNC_OR_AND_FETCH_8:
924 case BUILT_IN_SYNC_AND_AND_FETCH_8:
925 case BUILT_IN_SYNC_XOR_AND_FETCH_8:
926 case BUILT_IN_SYNC_NAND_AND_FETCH_8:
927 case BUILT_IN_SYNC_BOOL_COMPARE_AND_SWAP_8:
928 case BUILT_IN_SYNC_VAL_COMPARE_AND_SWAP_8:
929 case BUILT_IN_SYNC_LOCK_TEST_AND_SET_8:
930 case BUILT_IN_SYNC_LOCK_RELEASE_8:
931 case BUILT_IN_ATOMIC_EXCHANGE_8:
932 case BUILT_IN_ATOMIC_COMPARE_EXCHANGE_8:
933 case BUILT_IN_ATOMIC_STORE_8:
934 case BUILT_IN_ATOMIC_ADD_FETCH_8:
935 case BUILT_IN_ATOMIC_SUB_FETCH_8:
936 case BUILT_IN_ATOMIC_AND_FETCH_8:
937 case BUILT_IN_ATOMIC_NAND_FETCH_8:
938 case BUILT_IN_ATOMIC_XOR_FETCH_8:
939 case BUILT_IN_ATOMIC_OR_FETCH_8:
940 case BUILT_IN_ATOMIC_FETCH_ADD_8:
941 case BUILT_IN_ATOMIC_FETCH_SUB_8:
942 case BUILT_IN_ATOMIC_FETCH_AND_8:
943 case BUILT_IN_ATOMIC_FETCH_NAND_8:
944 case BUILT_IN_ATOMIC_FETCH_XOR_8:
c31c80df 945 case BUILT_IN_ATOMIC_FETCH_OR_8:
6e48ee8f 946 access_size = 8;
947 goto do_atomic;
948
949 case BUILT_IN_ATOMIC_LOAD_16:
950 is_store = false;
951 /* FALLTHRU */
952 case BUILT_IN_SYNC_FETCH_AND_ADD_16:
953 case BUILT_IN_SYNC_FETCH_AND_SUB_16:
954 case BUILT_IN_SYNC_FETCH_AND_OR_16:
955 case BUILT_IN_SYNC_FETCH_AND_AND_16:
956 case BUILT_IN_SYNC_FETCH_AND_XOR_16:
957 case BUILT_IN_SYNC_FETCH_AND_NAND_16:
958 case BUILT_IN_SYNC_ADD_AND_FETCH_16:
959 case BUILT_IN_SYNC_SUB_AND_FETCH_16:
960 case BUILT_IN_SYNC_OR_AND_FETCH_16:
961 case BUILT_IN_SYNC_AND_AND_FETCH_16:
962 case BUILT_IN_SYNC_XOR_AND_FETCH_16:
963 case BUILT_IN_SYNC_NAND_AND_FETCH_16:
964 case BUILT_IN_SYNC_BOOL_COMPARE_AND_SWAP_16:
965 case BUILT_IN_SYNC_VAL_COMPARE_AND_SWAP_16:
966 case BUILT_IN_SYNC_LOCK_TEST_AND_SET_16:
967 case BUILT_IN_SYNC_LOCK_RELEASE_16:
968 case BUILT_IN_ATOMIC_EXCHANGE_16:
969 case BUILT_IN_ATOMIC_COMPARE_EXCHANGE_16:
970 case BUILT_IN_ATOMIC_STORE_16:
971 case BUILT_IN_ATOMIC_ADD_FETCH_16:
972 case BUILT_IN_ATOMIC_SUB_FETCH_16:
973 case BUILT_IN_ATOMIC_AND_FETCH_16:
974 case BUILT_IN_ATOMIC_NAND_FETCH_16:
975 case BUILT_IN_ATOMIC_XOR_FETCH_16:
976 case BUILT_IN_ATOMIC_OR_FETCH_16:
977 case BUILT_IN_ATOMIC_FETCH_ADD_16:
978 case BUILT_IN_ATOMIC_FETCH_SUB_16:
979 case BUILT_IN_ATOMIC_FETCH_AND_16:
980 case BUILT_IN_ATOMIC_FETCH_NAND_16:
981 case BUILT_IN_ATOMIC_FETCH_XOR_16:
c31c80df 982 case BUILT_IN_ATOMIC_FETCH_OR_16:
6e48ee8f 983 access_size = 16;
984 /* FALLTHRU */
985 do_atomic:
c31c80df 986 {
987 dest = gimple_call_arg (call, 0);
988 /* DEST represents the address of a memory location.
989 instrument_derefs wants the memory location, so lets
990 dereference the address DEST before handing it to
991 instrument_derefs. */
6e48ee8f 992 tree type = build_nonstandard_integer_type (access_size
993 * BITS_PER_UNIT, 1);
994 dest = build2 (MEM_REF, type, dest,
995 build_int_cst (build_pointer_type (char_type_node), 0));
996 break;
c31c80df 997 }
998
999 default:
1000 /* The other builtins memory access are not instrumented in this
1001 function because they either don't have any length parameter,
1002 or their length parameter is just a limit. */
1003 break;
1004 }
1005
1006 if (len != NULL_TREE)
1007 {
1008 if (source0 != NULL_TREE)
1009 {
1010 src0->start = source0;
1011 src0->access_size = access_size;
1012 *src0_len = len;
1013 *src0_is_store = false;
1014 }
1015
1016 if (source1 != NULL_TREE)
1017 {
1018 src1->start = source1;
1019 src1->access_size = access_size;
1020 *src1_len = len;
1021 *src1_is_store = false;
1022 }
1023
1024 if (dest != NULL_TREE)
1025 {
1026 dst->start = dest;
1027 dst->access_size = access_size;
1028 *dst_len = len;
1029 *dst_is_store = true;
1030 }
1031
1032 got_reference_p = true;
1033 }
d9dc05a1 1034 else if (dest)
1035 {
1036 dst->start = dest;
1037 dst->access_size = access_size;
1038 *dst_len = NULL_TREE;
1039 *dst_is_store = is_store;
1040 *dest_is_deref = true;
1041 got_reference_p = true;
1042 }
c31c80df 1043
d9dc05a1 1044 return got_reference_p;
c31c80df 1045}
1046
1047/* Return true iff a given gimple statement has been instrumented.
1048 Note that the statement is "defined" by the memory references it
1049 contains. */
1050
1051static bool
42acab1c 1052has_stmt_been_instrumented_p (gimple *stmt)
c31c80df 1053{
1054 if (gimple_assign_single_p (stmt))
1055 {
1056 bool r_is_store;
1057 asan_mem_ref r;
1058 asan_mem_ref_init (&r, NULL, 1);
1059
1a91d914 1060 if (get_mem_ref_of_assignment (as_a <gassign *> (stmt), &r,
1061 &r_is_store))
c31c80df 1062 return has_mem_ref_been_instrumented (&r);
1063 }
1064 else if (gimple_call_builtin_p (stmt, BUILT_IN_NORMAL))
1065 {
1066 asan_mem_ref src0, src1, dest;
1067 asan_mem_ref_init (&src0, NULL, 1);
1068 asan_mem_ref_init (&src1, NULL, 1);
1069 asan_mem_ref_init (&dest, NULL, 1);
1070
1071 tree src0_len = NULL_TREE, src1_len = NULL_TREE, dest_len = NULL_TREE;
1072 bool src0_is_store = false, src1_is_store = false,
f9acf11a 1073 dest_is_store = false, dest_is_deref = false, intercepted_p = true;
1a91d914 1074 if (get_mem_refs_of_builtin_call (as_a <gcall *> (stmt),
c31c80df 1075 &src0, &src0_len, &src0_is_store,
1076 &src1, &src1_len, &src1_is_store,
1077 &dest, &dest_len, &dest_is_store,
f9acf11a 1078 &dest_is_deref, &intercepted_p))
c31c80df 1079 {
1080 if (src0.start != NULL_TREE
1081 && !has_mem_ref_been_instrumented (&src0, src0_len))
1082 return false;
1083
1084 if (src1.start != NULL_TREE
1085 && !has_mem_ref_been_instrumented (&src1, src1_len))
1086 return false;
1087
1088 if (dest.start != NULL_TREE
1089 && !has_mem_ref_been_instrumented (&dest, dest_len))
1090 return false;
1091
1092 return true;
1093 }
1094 }
774068a0 1095 else if (is_gimple_call (stmt) && gimple_store_p (stmt))
1096 {
1097 asan_mem_ref r;
1098 asan_mem_ref_init (&r, NULL, 1);
1099
1100 r.start = gimple_call_lhs (stmt);
1101 r.access_size = int_size_in_bytes (TREE_TYPE (r.start));
1102 return has_mem_ref_been_instrumented (&r);
1103 }
1104
c31c80df 1105 return false;
1106}
1107
1108/* Insert a memory reference into the hash table. */
1109
1110static void
86d3a572 1111update_mem_ref_hash_table (tree ref, HOST_WIDE_INT access_size)
c31c80df 1112{
c1f445d2 1113 hash_table<asan_mem_ref_hasher> *ht = get_mem_ref_hash_table ();
c31c80df 1114
1115 asan_mem_ref r;
1116 asan_mem_ref_init (&r, ref, access_size);
1117
c1f445d2 1118 asan_mem_ref **slot = ht->find_slot (&r, INSERT);
f9acf11a 1119 if (*slot == NULL || (*slot)->access_size < access_size)
c31c80df 1120 *slot = asan_mem_ref_new (ref, access_size);
1121}
1122
55b58027 1123/* Initialize shadow_ptr_types array. */
1124
1125static void
1126asan_init_shadow_ptr_types (void)
1127{
1128 asan_shadow_set = new_alias_set ();
629b6abc 1129 tree types[3] = { signed_char_type_node, short_integer_type_node,
1130 integer_type_node };
1131
1132 for (unsigned i = 0; i < 3; i++)
1133 {
1134 shadow_ptr_types[i] = build_distinct_type_copy (types[i]);
1135 TYPE_ALIAS_SET (shadow_ptr_types[i]) = asan_shadow_set;
1136 shadow_ptr_types[i] = build_pointer_type (shadow_ptr_types[i]);
1137 }
1138
55b58027 1139 initialize_sanitizer_builtins ();
1140}
1141
b75d2c15 1142/* Create ADDR_EXPR of STRING_CST with the PP pretty printer text. */
92fc5c48 1143
1144static tree
b75d2c15 1145asan_pp_string (pretty_printer *pp)
92fc5c48 1146{
b75d2c15 1147 const char *buf = pp_formatted_text (pp);
92fc5c48 1148 size_t len = strlen (buf);
1149 tree ret = build_string (len + 1, buf);
1150 TREE_TYPE (ret)
55b58027 1151 = build_array_type (TREE_TYPE (shadow_ptr_types[0]),
1152 build_index_type (size_int (len)));
92fc5c48 1153 TREE_READONLY (ret) = 1;
1154 TREE_STATIC (ret) = 1;
55b58027 1155 return build1 (ADDR_EXPR, shadow_ptr_types[0], ret);
92fc5c48 1156}
1157
cc72d6e9 1158/* Clear shadow memory at SHADOW_MEM, LEN bytes. Can't call a library call here
1159 though. */
1160
1161static void
1162asan_clear_shadow (rtx shadow_mem, HOST_WIDE_INT len)
1163{
dbf944e5 1164 rtx_insn *insn, *insns, *jump;
1165 rtx_code_label *top_label;
1166 rtx end, addr, tmp;
cc72d6e9 1167
b0d945ba 1168 gcc_assert ((len & 3) == 0);
cc72d6e9 1169 start_sequence ();
1170 clear_storage (shadow_mem, GEN_INT (len), BLOCK_OP_NORMAL);
1171 insns = get_insns ();
1172 end_sequence ();
1173 for (insn = insns; insn; insn = NEXT_INSN (insn))
1174 if (CALL_P (insn))
1175 break;
1176 if (insn == NULL_RTX)
1177 {
1178 emit_insn (insns);
1179 return;
1180 }
1181
cc72d6e9 1182 top_label = gen_label_rtx ();
a15fa55a 1183 addr = copy_to_mode_reg (Pmode, XEXP (shadow_mem, 0));
cc72d6e9 1184 shadow_mem = adjust_automodify_address (shadow_mem, SImode, addr, 0);
1185 end = force_reg (Pmode, plus_constant (Pmode, addr, len));
1186 emit_label (top_label);
1187
1188 emit_move_insn (shadow_mem, const0_rtx);
0359f9f5 1189 tmp = expand_simple_binop (Pmode, PLUS, addr, gen_int_mode (4, Pmode), addr,
ff326078 1190 true, OPTAB_LIB_WIDEN);
cc72d6e9 1191 if (tmp != addr)
1192 emit_move_insn (addr, tmp);
1193 emit_cmp_and_jump_insns (addr, end, LT, NULL_RTX, Pmode, true, top_label);
1194 jump = get_last_insn ();
1195 gcc_assert (JUMP_P (jump));
61cb1816 1196 add_reg_br_prob_note (jump,
1197 profile_probability::guessed_always ()
1198 .apply_scale (80, 100));
cc72d6e9 1199}
1200
1e80ce41 1201void
1202asan_function_start (void)
1203{
1204 section *fnsec = function_section (current_function_decl);
1205 switch_to_section (fnsec);
1206 ASM_OUTPUT_DEBUG_LABEL (asm_out_file, "LASANPC",
ff326078 1207 current_function_funcdef_no);
1e80ce41 1208}
1209
629b6abc 1210/* Return number of shadow bytes that are occupied by a local variable
1211 of SIZE bytes. */
1212
1213static unsigned HOST_WIDE_INT
1214shadow_mem_size (unsigned HOST_WIDE_INT size)
1215{
e56a070c 1216 /* It must be possible to align stack variables to granularity
1217 of shadow memory. */
1218 gcc_assert (BITS_PER_UNIT
1219 * ASAN_SHADOW_GRANULARITY <= MAX_SUPPORTED_STACK_ALIGNMENT);
1220
629b6abc 1221 return ROUND_UP (size, ASAN_SHADOW_GRANULARITY) / ASAN_SHADOW_GRANULARITY;
1222}
1223
57e4ba18 1224/* Always emit 4 bytes at a time. */
1225#define RZ_BUFFER_SIZE 4
1226
1227/* ASAN redzone buffer container that handles emission of shadow bytes. */
251317e4 1228class asan_redzone_buffer
57e4ba18 1229{
251317e4 1230public:
57e4ba18 1231 /* Constructor. */
1232 asan_redzone_buffer (rtx shadow_mem, HOST_WIDE_INT prev_offset):
1233 m_shadow_mem (shadow_mem), m_prev_offset (prev_offset),
1234 m_original_offset (prev_offset), m_shadow_bytes (RZ_BUFFER_SIZE)
1235 {}
1236
1237 /* Emit VALUE shadow byte at a given OFFSET. */
1238 void emit_redzone_byte (HOST_WIDE_INT offset, unsigned char value);
1239
1240 /* Emit RTX emission of the content of the buffer. */
1241 void flush_redzone_payload (void);
1242
1243private:
1244 /* Flush if the content of the buffer is full
1245 (equal to RZ_BUFFER_SIZE). */
1246 void flush_if_full (void);
1247
1248 /* Memory where we last emitted a redzone payload. */
1249 rtx m_shadow_mem;
1250
1251 /* Relative offset where we last emitted a redzone payload. */
1252 HOST_WIDE_INT m_prev_offset;
1253
1254 /* Relative original offset. Used for checking only. */
1255 HOST_WIDE_INT m_original_offset;
1256
1257public:
1258 /* Buffer with redzone payload. */
1259 auto_vec<unsigned char> m_shadow_bytes;
1260};
1261
1262/* Emit VALUE shadow byte at a given OFFSET. */
1263
1264void
1265asan_redzone_buffer::emit_redzone_byte (HOST_WIDE_INT offset,
1266 unsigned char value)
1267{
1268 gcc_assert ((offset & (ASAN_SHADOW_GRANULARITY - 1)) == 0);
1269 gcc_assert (offset >= m_prev_offset);
1270
1271 HOST_WIDE_INT off
1272 = m_prev_offset + ASAN_SHADOW_GRANULARITY * m_shadow_bytes.length ();
1273 if (off == offset)
1274 {
1275 /* Consecutive shadow memory byte. */
1276 m_shadow_bytes.safe_push (value);
1277 flush_if_full ();
1278 }
1279 else
1280 {
1281 if (!m_shadow_bytes.is_empty ())
1282 flush_redzone_payload ();
1283
1284 /* Maybe start earlier in order to use aligned store. */
1285 HOST_WIDE_INT align = (offset - m_prev_offset) % ASAN_RED_ZONE_SIZE;
1286 if (align)
1287 {
1288 offset -= align;
1289 for (unsigned i = 0; i < align / BITS_PER_UNIT; i++)
1290 m_shadow_bytes.safe_push (0);
1291 }
1292
1293 /* Adjust m_prev_offset and m_shadow_mem. */
1294 HOST_WIDE_INT diff = offset - m_prev_offset;
1295 m_shadow_mem = adjust_address (m_shadow_mem, VOIDmode,
1296 diff >> ASAN_SHADOW_SHIFT);
1297 m_prev_offset = offset;
1298 m_shadow_bytes.safe_push (value);
1299 flush_if_full ();
1300 }
1301}
1302
1303/* Emit RTX emission of the content of the buffer. */
1304
1305void
1306asan_redzone_buffer::flush_redzone_payload (void)
1307{
1308 gcc_assert (WORDS_BIG_ENDIAN == BYTES_BIG_ENDIAN);
1309
1310 if (m_shadow_bytes.is_empty ())
1311 return;
1312
1313 /* Be sure we always emit to an aligned address. */
1314 gcc_assert (((m_prev_offset - m_original_offset)
1315 & (ASAN_RED_ZONE_SIZE - 1)) == 0);
1316
1317 /* Fill it to RZ_BUFFER_SIZE bytes with zeros if needed. */
1318 unsigned l = m_shadow_bytes.length ();
1319 for (unsigned i = 0; i <= RZ_BUFFER_SIZE - l; i++)
1320 m_shadow_bytes.safe_push (0);
1321
1322 if (dump_file && (dump_flags & TDF_DETAILS))
1323 fprintf (dump_file,
1324 "Flushing rzbuffer at offset %" PRId64 " with: ", m_prev_offset);
1325
1326 unsigned HOST_WIDE_INT val = 0;
1327 for (unsigned i = 0; i < RZ_BUFFER_SIZE; i++)
1328 {
1329 unsigned char v
ef0c2db0 1330 = m_shadow_bytes[BYTES_BIG_ENDIAN ? RZ_BUFFER_SIZE - i - 1 : i];
57e4ba18 1331 val |= (unsigned HOST_WIDE_INT)v << (BITS_PER_UNIT * i);
1332 if (dump_file && (dump_flags & TDF_DETAILS))
1333 fprintf (dump_file, "%02x ", v);
1334 }
1335
1336 if (dump_file && (dump_flags & TDF_DETAILS))
1337 fprintf (dump_file, "\n");
1338
1339 rtx c = gen_int_mode (val, SImode);
1340 m_shadow_mem = adjust_address (m_shadow_mem, SImode, 0);
1341 emit_move_insn (m_shadow_mem, c);
1342 m_shadow_bytes.truncate (0);
1343}
1344
1345/* Flush if the content of the buffer is full
1346 (equal to RZ_BUFFER_SIZE). */
1347
1348void
1349asan_redzone_buffer::flush_if_full (void)
1350{
1351 if (m_shadow_bytes.length () == RZ_BUFFER_SIZE)
1352 flush_redzone_payload ();
1353}
1354
3c919612 1355/* Insert code to protect stack vars. The prologue sequence should be emitted
1356 directly, epilogue sequence returned. BASE is the register holding the
1357 stack base, against which OFFSETS array offsets are relative to, OFFSETS
1358 array contains pairs of offsets in reverse order, always the end offset
1359 of some gap that needs protection followed by starting offset,
1360 and DECLS is an array of representative decls for each var partition.
1361 LENGTH is the length of the OFFSETS array, DECLS array is LENGTH / 2 - 1
1362 elements long (OFFSETS include gap before the first variable as well
683539f6 1363 as gaps after each stack variable). PBASE is, if non-NULL, some pseudo
1364 register which stack vars DECL_RTLs are based on. Either BASE should be
1365 assigned to PBASE, when not doing use after return protection, or
1366 corresponding address based on __asan_stack_malloc* return value. */
3c919612 1367
67ab16d9 1368rtx_insn *
683539f6 1369asan_emit_stack_protection (rtx base, rtx pbase, unsigned int alignb,
1370 HOST_WIDE_INT *offsets, tree *decls, int length)
3c919612 1371{
79f6a8ed 1372 rtx shadow_base, shadow_mem, ret, mem, orig_base;
1373 rtx_code_label *lab;
67ab16d9 1374 rtx_insn *insns;
f25b3fef 1375 char buf[32];
683539f6 1376 HOST_WIDE_INT base_offset = offsets[length - 1];
1377 HOST_WIDE_INT base_align_bias = 0, offset, prev_offset;
1378 HOST_WIDE_INT asan_frame_size = offsets[0] - base_offset;
b0d945ba 1379 HOST_WIDE_INT last_offset, last_size, last_size_aligned;
3c919612 1380 int l;
1381 unsigned char cur_shadow_byte = ASAN_STACK_MAGIC_LEFT;
1e80ce41 1382 tree str_cst, decl, id;
683539f6 1383 int use_after_return_class = -1;
3c919612 1384
55b58027 1385 if (shadow_ptr_types[0] == NULL_TREE)
1386 asan_init_shadow_ptr_types ();
1387
1db5adee 1388 expanded_location cfun_xloc
1389 = expand_location (DECL_SOURCE_LOCATION (current_function_decl));
1390
3c919612 1391 /* First of all, prepare the description string. */
b75d2c15 1392 pretty_printer asan_pp;
eed6bc21 1393
92fc5c48 1394 pp_decimal_int (&asan_pp, length / 2 - 1);
1395 pp_space (&asan_pp);
3c919612 1396 for (l = length - 2; l; l -= 2)
1397 {
1398 tree decl = decls[l / 2 - 1];
92fc5c48 1399 pp_wide_integer (&asan_pp, offsets[l] - base_offset);
1400 pp_space (&asan_pp);
1401 pp_wide_integer (&asan_pp, offsets[l - 1] - offsets[l]);
1402 pp_space (&asan_pp);
1db5adee 1403
1404 expanded_location xloc
1405 = expand_location (DECL_SOURCE_LOCATION (decl));
1406 char location[32];
1407
1408 if (xloc.file == cfun_xloc.file)
1409 sprintf (location, ":%d", xloc.line);
1410 else
1411 location[0] = '\0';
1412
3c919612 1413 if (DECL_P (decl) && DECL_NAME (decl))
1414 {
1db5adee 1415 unsigned idlen
1416 = IDENTIFIER_LENGTH (DECL_NAME (decl)) + strlen (location);
1417 pp_decimal_int (&asan_pp, idlen);
92fc5c48 1418 pp_space (&asan_pp);
a94db6b0 1419 pp_tree_identifier (&asan_pp, DECL_NAME (decl));
1db5adee 1420 pp_string (&asan_pp, location);
3c919612 1421 }
1422 else
92fc5c48 1423 pp_string (&asan_pp, "9 <unknown>");
1db5adee 1424
1425 if (l > 2)
1426 pp_space (&asan_pp);
3c919612 1427 }
b75d2c15 1428 str_cst = asan_pp_string (&asan_pp);
3c919612 1429
1430 /* Emit the prologue sequence. */
bf2b7c22 1431 if (asan_frame_size > 32 && asan_frame_size <= 65536 && pbase
1432 && ASAN_USE_AFTER_RETURN)
683539f6 1433 {
1434 use_after_return_class = floor_log2 (asan_frame_size - 1) - 5;
1435 /* __asan_stack_malloc_N guarantees alignment
ff326078 1436 N < 6 ? (64 << N) : 4096 bytes. */
683539f6 1437 if (alignb > (use_after_return_class < 6
1438 ? (64U << use_after_return_class) : 4096U))
1439 use_after_return_class = -1;
1440 else if (alignb > ASAN_RED_ZONE_SIZE && (asan_frame_size & (alignb - 1)))
1441 base_align_bias = ((asan_frame_size + alignb - 1)
1442 & ~(alignb - HOST_WIDE_INT_1)) - asan_frame_size;
1443 }
724165bd 1444
f89175bb 1445 /* Align base if target is STRICT_ALIGNMENT. */
1446 if (STRICT_ALIGNMENT)
724165bd 1447 {
1448 const HOST_WIDE_INT align
1449 = (GET_MODE_ALIGNMENT (SImode) / BITS_PER_UNIT) << ASAN_SHADOW_SHIFT;
1450 base = expand_binop (Pmode, and_optab, base, gen_int_mode (-align, Pmode),
1451 NULL_RTX, 1, OPTAB_DIRECT);
1452 }
f89175bb 1453
683539f6 1454 if (use_after_return_class == -1 && pbase)
1455 emit_move_insn (pbase, base);
f89175bb 1456
0359f9f5 1457 base = expand_binop (Pmode, add_optab, base,
683539f6 1458 gen_int_mode (base_offset - base_align_bias, Pmode),
3c919612 1459 NULL_RTX, 1, OPTAB_DIRECT);
683539f6 1460 orig_base = NULL_RTX;
1461 if (use_after_return_class != -1)
1462 {
1463 if (asan_detect_stack_use_after_return == NULL_TREE)
1464 {
1465 id = get_identifier ("__asan_option_detect_stack_use_after_return");
1466 decl = build_decl (BUILTINS_LOCATION, VAR_DECL, id,
1467 integer_type_node);
1468 SET_DECL_ASSEMBLER_NAME (decl, id);
1469 TREE_ADDRESSABLE (decl) = 1;
1470 DECL_ARTIFICIAL (decl) = 1;
1471 DECL_IGNORED_P (decl) = 1;
1472 DECL_EXTERNAL (decl) = 1;
1473 TREE_STATIC (decl) = 1;
1474 TREE_PUBLIC (decl) = 1;
1475 TREE_USED (decl) = 1;
1476 asan_detect_stack_use_after_return = decl;
1477 }
1478 orig_base = gen_reg_rtx (Pmode);
1479 emit_move_insn (orig_base, base);
1480 ret = expand_normal (asan_detect_stack_use_after_return);
1481 lab = gen_label_rtx ();
683539f6 1482 emit_cmp_and_jump_insns (ret, const0_rtx, EQ, NULL_RTX,
720cfc43 1483 VOIDmode, 0, lab,
1484 profile_probability::very_likely ());
683539f6 1485 snprintf (buf, sizeof buf, "__asan_stack_malloc_%d",
1486 use_after_return_class);
1487 ret = init_one_libfunc (buf);
9e9e5c15 1488 ret = emit_library_call_value (ret, NULL_RTX, LCT_NORMAL, ptr_mode,
683539f6 1489 GEN_INT (asan_frame_size
1490 + base_align_bias),
7966ce00 1491 TYPE_MODE (pointer_sized_int_node));
1492 /* __asan_stack_malloc_[n] returns a pointer to fake stack if succeeded
1493 and NULL otherwise. Check RET value is NULL here and jump over the
1494 BASE reassignment in this case. Otherwise, reassign BASE to RET. */
7966ce00 1495 emit_cmp_and_jump_insns (ret, const0_rtx, EQ, NULL_RTX,
720cfc43 1496 VOIDmode, 0, lab,
1497 profile_probability:: very_unlikely ());
683539f6 1498 ret = convert_memory_address (Pmode, ret);
1499 emit_move_insn (base, ret);
1500 emit_label (lab);
1501 emit_move_insn (pbase, expand_binop (Pmode, add_optab, base,
1502 gen_int_mode (base_align_bias
1503 - base_offset, Pmode),
1504 NULL_RTX, 1, OPTAB_DIRECT));
1505 }
3c919612 1506 mem = gen_rtx_MEM (ptr_mode, base);
683539f6 1507 mem = adjust_address (mem, VOIDmode, base_align_bias);
d11aedc7 1508 emit_move_insn (mem, gen_int_mode (ASAN_STACK_FRAME_MAGIC, ptr_mode));
3c919612 1509 mem = adjust_address (mem, VOIDmode, GET_MODE_SIZE (ptr_mode));
1510 emit_move_insn (mem, expand_normal (str_cst));
1e80ce41 1511 mem = adjust_address (mem, VOIDmode, GET_MODE_SIZE (ptr_mode));
1512 ASM_GENERATE_INTERNAL_LABEL (buf, "LASANPC", current_function_funcdef_no);
1513 id = get_identifier (buf);
1514 decl = build_decl (DECL_SOURCE_LOCATION (current_function_decl),
ff326078 1515 VAR_DECL, id, char_type_node);
1e80ce41 1516 SET_DECL_ASSEMBLER_NAME (decl, id);
1517 TREE_ADDRESSABLE (decl) = 1;
1518 TREE_READONLY (decl) = 1;
1519 DECL_ARTIFICIAL (decl) = 1;
1520 DECL_IGNORED_P (decl) = 1;
1521 TREE_STATIC (decl) = 1;
1522 TREE_PUBLIC (decl) = 0;
1523 TREE_USED (decl) = 1;
7c4fae98 1524 DECL_INITIAL (decl) = decl;
1525 TREE_ASM_WRITTEN (decl) = 1;
1526 TREE_ASM_WRITTEN (id) = 1;
1e80ce41 1527 emit_move_insn (mem, expand_normal (build_fold_addr_expr (decl)));
3c919612 1528 shadow_base = expand_binop (Pmode, lshr_optab, base,
bd39703a 1529 gen_int_shift_amount (Pmode, ASAN_SHADOW_SHIFT),
3c919612 1530 NULL_RTX, 1, OPTAB_DIRECT);
683539f6 1531 shadow_base
1532 = plus_constant (Pmode, shadow_base,
cf357977 1533 asan_shadow_offset ()
683539f6 1534 + (base_align_bias >> ASAN_SHADOW_SHIFT));
3c919612 1535 gcc_assert (asan_shadow_set != -1
1536 && (ASAN_RED_ZONE_SIZE >> ASAN_SHADOW_SHIFT) == 4);
1537 shadow_mem = gen_rtx_MEM (SImode, shadow_base);
1538 set_mem_alias_set (shadow_mem, asan_shadow_set);
f89175bb 1539 if (STRICT_ALIGNMENT)
1540 set_mem_align (shadow_mem, (GET_MODE_ALIGNMENT (SImode)));
3c919612 1541 prev_offset = base_offset;
57e4ba18 1542
1543 asan_redzone_buffer rz_buffer (shadow_mem, prev_offset);
3c919612 1544 for (l = length; l; l -= 2)
1545 {
1546 if (l == 2)
1547 cur_shadow_byte = ASAN_STACK_MAGIC_RIGHT;
1548 offset = offsets[l - 1];
57e4ba18 1549
1550 bool extra_byte = (offset - base_offset) & (ASAN_SHADOW_GRANULARITY - 1);
1551 /* If a red-zone is not aligned to ASAN_SHADOW_GRANULARITY then
1552 the previous stack variable has size % ASAN_SHADOW_GRANULARITY != 0.
1553 In that case we have to emit one extra byte that will describe
1554 how many bytes (our of ASAN_SHADOW_GRANULARITY) can be accessed. */
1555 if (extra_byte)
3c919612 1556 {
3c919612 1557 HOST_WIDE_INT aoff
1558 = base_offset + ((offset - base_offset)
57e4ba18 1559 & ~(ASAN_SHADOW_GRANULARITY - HOST_WIDE_INT_1));
1560 rz_buffer.emit_redzone_byte (aoff, offset - aoff);
1561 offset = aoff + ASAN_SHADOW_GRANULARITY;
3c919612 1562 }
57e4ba18 1563
1564 /* Calculate size of red zone payload. */
1565 while (offset < offsets[l - 2])
3c919612 1566 {
57e4ba18 1567 rz_buffer.emit_redzone_byte (offset, cur_shadow_byte);
1568 offset += ASAN_SHADOW_GRANULARITY;
3c919612 1569 }
57e4ba18 1570
3c919612 1571 cur_shadow_byte = ASAN_STACK_MAGIC_MIDDLE;
1572 }
57e4ba18 1573
1574 /* As the automatic variables are aligned to
1575 ASAN_RED_ZONE_SIZE / ASAN_SHADOW_GRANULARITY, the buffer should be
1576 flushed here. */
1577 gcc_assert (rz_buffer.m_shadow_bytes.is_empty ());
1578
3c919612 1579 do_pending_stack_adjust ();
1580
1581 /* Construct epilogue sequence. */
1582 start_sequence ();
1583
79f6a8ed 1584 lab = NULL;
683539f6 1585 if (use_after_return_class != -1)
1586 {
79f6a8ed 1587 rtx_code_label *lab2 = gen_label_rtx ();
683539f6 1588 char c = (char) ASAN_STACK_MAGIC_USE_AFTER_RET;
683539f6 1589 emit_cmp_and_jump_insns (orig_base, base, EQ, NULL_RTX,
720cfc43 1590 VOIDmode, 0, lab2,
1591 profile_probability::very_likely ());
683539f6 1592 shadow_mem = gen_rtx_MEM (BLKmode, shadow_base);
1593 set_mem_alias_set (shadow_mem, asan_shadow_set);
1594 mem = gen_rtx_MEM (ptr_mode, base);
1595 mem = adjust_address (mem, VOIDmode, base_align_bias);
1596 emit_move_insn (mem, gen_int_mode (ASAN_STACK_RETIRED_MAGIC, ptr_mode));
1597 unsigned HOST_WIDE_INT sz = asan_frame_size >> ASAN_SHADOW_SHIFT;
1598 if (use_after_return_class < 5
1599 && can_store_by_pieces (sz, builtin_memset_read_str, &c,
1600 BITS_PER_UNIT, true))
1601 store_by_pieces (shadow_mem, sz, builtin_memset_read_str, &c,
02aa6d73 1602 BITS_PER_UNIT, true, RETURN_BEGIN);
683539f6 1603 else if (use_after_return_class >= 5
1604 || !set_storage_via_setmem (shadow_mem,
1605 GEN_INT (sz),
1606 gen_int_mode (c, QImode),
1607 BITS_PER_UNIT, BITS_PER_UNIT,
1608 -1, sz, sz, sz))
1609 {
1610 snprintf (buf, sizeof buf, "__asan_stack_free_%d",
1611 use_after_return_class);
1612 ret = init_one_libfunc (buf);
1613 rtx addr = convert_memory_address (ptr_mode, base);
1614 rtx orig_addr = convert_memory_address (ptr_mode, orig_base);
9e9e5c15 1615 emit_library_call (ret, LCT_NORMAL, ptr_mode, addr, ptr_mode,
683539f6 1616 GEN_INT (asan_frame_size + base_align_bias),
1617 TYPE_MODE (pointer_sized_int_node),
1618 orig_addr, ptr_mode);
1619 }
1620 lab = gen_label_rtx ();
1621 emit_jump (lab);
1622 emit_label (lab2);
1623 }
1624
3c919612 1625 shadow_mem = gen_rtx_MEM (BLKmode, shadow_base);
1626 set_mem_alias_set (shadow_mem, asan_shadow_set);
f89175bb 1627
1628 if (STRICT_ALIGNMENT)
1629 set_mem_align (shadow_mem, (GET_MODE_ALIGNMENT (SImode)));
1630
355c1762 1631 prev_offset = base_offset;
3c919612 1632 last_offset = base_offset;
355c1762 1633 last_size = 0;
b0d945ba 1634 last_size_aligned = 0;
355c1762 1635 for (l = length; l; l -= 2)
3c919612 1636 {
355c1762 1637 offset = base_offset + ((offsets[l - 1] - base_offset)
b0d945ba 1638 & ~(ASAN_RED_ZONE_SIZE - HOST_WIDE_INT_1));
1639 if (last_offset + last_size_aligned < offset)
3c919612 1640 {
355c1762 1641 shadow_mem = adjust_address (shadow_mem, VOIDmode,
1642 (last_offset - prev_offset)
1643 >> ASAN_SHADOW_SHIFT);
1644 prev_offset = last_offset;
b0d945ba 1645 asan_clear_shadow (shadow_mem, last_size_aligned >> ASAN_SHADOW_SHIFT);
355c1762 1646 last_offset = offset;
1647 last_size = 0;
1648 }
b0d945ba 1649 else
1650 last_size = offset - last_offset;
355c1762 1651 last_size += base_offset + ((offsets[l - 2] - base_offset)
57e4ba18 1652 & ~(ASAN_MIN_RED_ZONE_SIZE - HOST_WIDE_INT_1))
355c1762 1653 - offset;
629b6abc 1654
355c1762 1655 /* Unpoison shadow memory that corresponds to a variable that is
1656 is subject of use-after-return sanitization. */
1657 if (l > 2)
1658 {
1659 decl = decls[l / 2 - 2];
629b6abc 1660 if (asan_handled_variables != NULL
1661 && asan_handled_variables->contains (decl))
1662 {
355c1762 1663 HOST_WIDE_INT size = offsets[l - 3] - offsets[l - 2];
629b6abc 1664 if (dump_file && (dump_flags & TDF_DETAILS))
1665 {
1666 const char *n = (DECL_NAME (decl)
1667 ? IDENTIFIER_POINTER (DECL_NAME (decl))
1668 : "<unknown>");
1669 fprintf (dump_file, "Unpoisoning shadow stack for variable: "
355c1762 1670 "%s (%" PRId64 " B)\n", n, size);
629b6abc 1671 }
1672
57e4ba18 1673 last_size += size & ~(ASAN_MIN_RED_ZONE_SIZE - HOST_WIDE_INT_1);
629b6abc 1674 }
3c919612 1675 }
b0d945ba 1676 last_size_aligned
1677 = ((last_size + (ASAN_RED_ZONE_SIZE - HOST_WIDE_INT_1))
1678 & ~(ASAN_RED_ZONE_SIZE - HOST_WIDE_INT_1));
355c1762 1679 }
b0d945ba 1680 if (last_size_aligned)
355c1762 1681 {
1682 shadow_mem = adjust_address (shadow_mem, VOIDmode,
1683 (last_offset - prev_offset)
1684 >> ASAN_SHADOW_SHIFT);
b0d945ba 1685 asan_clear_shadow (shadow_mem, last_size_aligned >> ASAN_SHADOW_SHIFT);
3c919612 1686 }
1687
629b6abc 1688 /* Clean-up set with instrumented stack variables. */
1689 delete asan_handled_variables;
1690 asan_handled_variables = NULL;
1691 delete asan_used_labels;
1692 asan_used_labels = NULL;
1693
3c919612 1694 do_pending_stack_adjust ();
683539f6 1695 if (lab)
1696 emit_label (lab);
3c919612 1697
67ab16d9 1698 insns = get_insns ();
3c919612 1699 end_sequence ();
67ab16d9 1700 return insns;
3c919612 1701}
1702
d08919a7 1703/* Emit __asan_allocas_unpoison (top, bot) call. The BASE parameter corresponds
1704 to BOT argument, for TOP virtual_stack_dynamic_rtx is used. NEW_SEQUENCE
1705 indicates whether we're emitting new instructions sequence or not. */
1706
1707rtx_insn *
1708asan_emit_allocas_unpoison (rtx top, rtx bot, rtx_insn *before)
1709{
1710 if (before)
1711 push_to_sequence (before);
1712 else
1713 start_sequence ();
1714 rtx ret = init_one_libfunc ("__asan_allocas_unpoison");
cd2ee6ee 1715 top = convert_memory_address (ptr_mode, top);
1716 bot = convert_memory_address (ptr_mode, bot);
22eb1ed5 1717 emit_library_call (ret, LCT_NORMAL, ptr_mode,
1718 top, ptr_mode, bot, ptr_mode);
d08919a7 1719
1720 do_pending_stack_adjust ();
1721 rtx_insn *insns = get_insns ();
1722 end_sequence ();
1723 return insns;
1724}
1725
92fc5c48 1726/* Return true if DECL, a global var, might be overridden and needs
1727 therefore a local alias. */
1728
1729static bool
1730asan_needs_local_alias (tree decl)
1731{
1732 return DECL_WEAK (decl) || !targetm.binds_local_p (decl);
1733}
1734
47c3d0de 1735/* Return true if DECL, a global var, is an artificial ODR indicator symbol
1736 therefore doesn't need protection. */
1737
1738static bool
1739is_odr_indicator (tree decl)
1740{
1741 return (DECL_ARTIFICIAL (decl)
1742 && lookup_attribute ("asan odr indicator", DECL_ATTRIBUTES (decl)));
1743}
1744
92fc5c48 1745/* Return true if DECL is a VAR_DECL that should be protected
1746 by Address Sanitizer, by appending a red zone with protected
1747 shadow memory after it and aligning it to at least
1748 ASAN_RED_ZONE_SIZE bytes. */
1749
1750bool
0c864c7c 1751asan_protect_global (tree decl, bool ignore_decl_rtl_set_p)
92fc5c48 1752{
bf2b7c22 1753 if (!ASAN_GLOBALS)
1754 return false;
1755
92fc5c48 1756 rtx rtl, symbol;
92fc5c48 1757
55b58027 1758 if (TREE_CODE (decl) == STRING_CST)
1759 {
1760 /* Instrument all STRING_CSTs except those created
1761 by asan_pp_string here. */
1762 if (shadow_ptr_types[0] != NULL_TREE
1763 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
1764 && TREE_TYPE (TREE_TYPE (decl)) == TREE_TYPE (shadow_ptr_types[0]))
1765 return false;
1766 return true;
1767 }
53e9c5c4 1768 if (!VAR_P (decl)
92fc5c48 1769 /* TLS vars aren't statically protectable. */
1770 || DECL_THREAD_LOCAL_P (decl)
1771 /* Externs will be protected elsewhere. */
1772 || DECL_EXTERNAL (decl)
0c864c7c 1773 /* PR sanitizer/81697: For architectures that use section anchors first
1774 call to asan_protect_global may occur before DECL_RTL (decl) is set.
1775 We should ignore DECL_RTL_SET_P then, because otherwise the first call
1776 to asan_protect_global will return FALSE and the following calls on the
1777 same decl after setting DECL_RTL (decl) will return TRUE and we'll end
1778 up with inconsistency at runtime. */
1779 || (!DECL_RTL_SET_P (decl) && !ignore_decl_rtl_set_p)
92fc5c48 1780 /* Comdat vars pose an ABI problem, we can't know if
1781 the var that is selected by the linker will have
1782 padding or not. */
1783 || DECL_ONE_ONLY (decl)
aa1dfc5f 1784 /* Similarly for common vars. People can use -fno-common.
1785 Note: Linux kernel is built with -fno-common, so we do instrument
1786 globals there even if it is C. */
1ba1559d 1787 || (DECL_COMMON (decl) && TREE_PUBLIC (decl))
92fc5c48 1788 /* Don't protect if using user section, often vars placed
1789 into user section from multiple TUs are then assumed
1790 to be an array of such vars, putting padding in there
1791 breaks this assumption. */
738a6bda 1792 || (DECL_SECTION_NAME (decl) != NULL
4d3c996b 1793 && !symtab_node::get (decl)->implicit_section
1794 && !section_sanitized_p (DECL_SECTION_NAME (decl)))
92fc5c48 1795 || DECL_SIZE (decl) == 0
1796 || ASAN_RED_ZONE_SIZE * BITS_PER_UNIT > MAX_OFILE_ALIGNMENT
8672ee56 1797 || TREE_CODE (DECL_SIZE_UNIT (decl)) != INTEGER_CST
92fc5c48 1798 || !valid_constant_size_p (DECL_SIZE_UNIT (decl))
11d00a0b 1799 || DECL_ALIGN_UNIT (decl) > 2 * ASAN_RED_ZONE_SIZE
47c3d0de 1800 || TREE_TYPE (decl) == ubsan_get_source_location_type ()
1801 || is_odr_indicator (decl))
92fc5c48 1802 return false;
1803
0c864c7c 1804 if (!ignore_decl_rtl_set_p || DECL_RTL_SET_P (decl))
1805 {
92fc5c48 1806
0c864c7c 1807 rtl = DECL_RTL (decl);
1808 if (!MEM_P (rtl) || GET_CODE (XEXP (rtl, 0)) != SYMBOL_REF)
1809 return false;
1810 symbol = XEXP (rtl, 0);
1811
1812 if (CONSTANT_POOL_ADDRESS_P (symbol)
1813 || TREE_CONSTANT_POOL_ADDRESS_P (symbol))
1814 return false;
1815 }
92fc5c48 1816
92fc5c48 1817 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
1818 return false;
1819
07b8a412 1820 if (!TARGET_SUPPORTS_ALIASES && asan_needs_local_alias (decl))
92fc5c48 1821 return false;
92fc5c48 1822
eca932e6 1823 return true;
92fc5c48 1824}
1825
86d3a572 1826/* Construct a function tree for __asan_report_{load,store}{1,2,4,8,16,_n}.
1827 IS_STORE is either 1 (for a store) or 0 (for a load). */
b92cccf4 1828
1829static tree
f4d482a6 1830report_error_func (bool is_store, bool recover_p, HOST_WIDE_INT size_in_bytes,
1831 int *nargs)
b92cccf4 1832{
f4d482a6 1833 static enum built_in_function report[2][2][6]
1834 = { { { BUILT_IN_ASAN_REPORT_LOAD1, BUILT_IN_ASAN_REPORT_LOAD2,
1835 BUILT_IN_ASAN_REPORT_LOAD4, BUILT_IN_ASAN_REPORT_LOAD8,
1836 BUILT_IN_ASAN_REPORT_LOAD16, BUILT_IN_ASAN_REPORT_LOAD_N },
1837 { BUILT_IN_ASAN_REPORT_STORE1, BUILT_IN_ASAN_REPORT_STORE2,
1838 BUILT_IN_ASAN_REPORT_STORE4, BUILT_IN_ASAN_REPORT_STORE8,
1839 BUILT_IN_ASAN_REPORT_STORE16, BUILT_IN_ASAN_REPORT_STORE_N } },
1840 { { BUILT_IN_ASAN_REPORT_LOAD1_NOABORT,
1841 BUILT_IN_ASAN_REPORT_LOAD2_NOABORT,
1842 BUILT_IN_ASAN_REPORT_LOAD4_NOABORT,
1843 BUILT_IN_ASAN_REPORT_LOAD8_NOABORT,
1844 BUILT_IN_ASAN_REPORT_LOAD16_NOABORT,
1845 BUILT_IN_ASAN_REPORT_LOAD_N_NOABORT },
1846 { BUILT_IN_ASAN_REPORT_STORE1_NOABORT,
1847 BUILT_IN_ASAN_REPORT_STORE2_NOABORT,
1848 BUILT_IN_ASAN_REPORT_STORE4_NOABORT,
1849 BUILT_IN_ASAN_REPORT_STORE8_NOABORT,
1850 BUILT_IN_ASAN_REPORT_STORE16_NOABORT,
1851 BUILT_IN_ASAN_REPORT_STORE_N_NOABORT } } };
4f86f720 1852 if (size_in_bytes == -1)
1853 {
1854 *nargs = 2;
f4d482a6 1855 return builtin_decl_implicit (report[recover_p][is_store][5]);
4f86f720 1856 }
1857 *nargs = 1;
f4d482a6 1858 int size_log2 = exact_log2 (size_in_bytes);
1859 return builtin_decl_implicit (report[recover_p][is_store][size_log2]);
b92cccf4 1860}
1861
4f86f720 1862/* Construct a function tree for __asan_{load,store}{1,2,4,8,16,_n}.
1863 IS_STORE is either 1 (for a store) or 0 (for a load). */
1864
1865static tree
f4d482a6 1866check_func (bool is_store, bool recover_p, HOST_WIDE_INT size_in_bytes,
1867 int *nargs)
4f86f720 1868{
f4d482a6 1869 static enum built_in_function check[2][2][6]
1870 = { { { BUILT_IN_ASAN_LOAD1, BUILT_IN_ASAN_LOAD2,
1871 BUILT_IN_ASAN_LOAD4, BUILT_IN_ASAN_LOAD8,
1872 BUILT_IN_ASAN_LOAD16, BUILT_IN_ASAN_LOADN },
1873 { BUILT_IN_ASAN_STORE1, BUILT_IN_ASAN_STORE2,
1874 BUILT_IN_ASAN_STORE4, BUILT_IN_ASAN_STORE8,
1875 BUILT_IN_ASAN_STORE16, BUILT_IN_ASAN_STOREN } },
1876 { { BUILT_IN_ASAN_LOAD1_NOABORT,
1877 BUILT_IN_ASAN_LOAD2_NOABORT,
1878 BUILT_IN_ASAN_LOAD4_NOABORT,
1879 BUILT_IN_ASAN_LOAD8_NOABORT,
1880 BUILT_IN_ASAN_LOAD16_NOABORT,
1881 BUILT_IN_ASAN_LOADN_NOABORT },
1882 { BUILT_IN_ASAN_STORE1_NOABORT,
1883 BUILT_IN_ASAN_STORE2_NOABORT,
1884 BUILT_IN_ASAN_STORE4_NOABORT,
1885 BUILT_IN_ASAN_STORE8_NOABORT,
1886 BUILT_IN_ASAN_STORE16_NOABORT,
1887 BUILT_IN_ASAN_STOREN_NOABORT } } };
4f86f720 1888 if (size_in_bytes == -1)
1889 {
1890 *nargs = 2;
f4d482a6 1891 return builtin_decl_implicit (check[recover_p][is_store][5]);
4f86f720 1892 }
1893 *nargs = 1;
f4d482a6 1894 int size_log2 = exact_log2 (size_in_bytes);
1895 return builtin_decl_implicit (check[recover_p][is_store][size_log2]);
4f86f720 1896}
1897
aab92688 1898/* Split the current basic block and create a condition statement
1ac3509e 1899 insertion point right before or after the statement pointed to by
1900 ITER. Return an iterator to the point at which the caller might
1901 safely insert the condition statement.
aab92688 1902
1903 THEN_BLOCK must be set to the address of an uninitialized instance
1904 of basic_block. The function will then set *THEN_BLOCK to the
1905 'then block' of the condition statement to be inserted by the
1906 caller.
1907
e8d4d8a9 1908 If CREATE_THEN_FALLTHRU_EDGE is false, no edge will be created from
1909 *THEN_BLOCK to *FALLTHROUGH_BLOCK.
1910
aab92688 1911 Similarly, the function will set *FALLTRHOUGH_BLOCK to the 'else
1912 block' of the condition statement to be inserted by the caller.
1913
1914 Note that *FALLTHROUGH_BLOCK is a new block that contains the
1915 statements starting from *ITER, and *THEN_BLOCK is a new empty
1916 block.
1917
1ac3509e 1918 *ITER is adjusted to point to always point to the first statement
1919 of the basic block * FALLTHROUGH_BLOCK. That statement is the
1920 same as what ITER was pointing to prior to calling this function,
1921 if BEFORE_P is true; otherwise, it is its following statement. */
aab92688 1922
ec08f7b0 1923gimple_stmt_iterator
1ac3509e 1924create_cond_insert_point (gimple_stmt_iterator *iter,
1925 bool before_p,
1926 bool then_more_likely_p,
e8d4d8a9 1927 bool create_then_fallthru_edge,
1ac3509e 1928 basic_block *then_block,
1929 basic_block *fallthrough_block)
aab92688 1930{
1931 gimple_stmt_iterator gsi = *iter;
1932
1ac3509e 1933 if (!gsi_end_p (gsi) && before_p)
aab92688 1934 gsi_prev (&gsi);
1935
1936 basic_block cur_bb = gsi_bb (*iter);
1937
1938 edge e = split_block (cur_bb, gsi_stmt (gsi));
1939
1940 /* Get a hold on the 'condition block', the 'then block' and the
1941 'else block'. */
1942 basic_block cond_bb = e->src;
1943 basic_block fallthru_bb = e->dest;
1944 basic_block then_bb = create_empty_bb (cond_bb);
f6568ea4 1945 if (current_loops)
1946 {
1947 add_bb_to_loop (then_bb, cond_bb->loop_father);
1948 loops_state_set (LOOPS_NEED_FIXUP);
1949 }
aab92688 1950
1951 /* Set up the newly created 'then block'. */
1952 e = make_edge (cond_bb, then_bb, EDGE_TRUE_VALUE);
7dc9e270 1953 profile_probability fallthrough_probability
aab92688 1954 = then_more_likely_p
7dc9e270 1955 ? profile_probability::very_unlikely ()
1956 : profile_probability::very_likely ();
1957 e->probability = fallthrough_probability.invert ();
205ce1aa 1958 then_bb->count = e->count ();
e8d4d8a9 1959 if (create_then_fallthru_edge)
1960 make_single_succ_edge (then_bb, fallthru_bb, EDGE_FALLTHRU);
aab92688 1961
1962 /* Set up the fallthrough basic block. */
1963 e = find_edge (cond_bb, fallthru_bb);
1964 e->flags = EDGE_FALSE_VALUE;
7dc9e270 1965 e->probability = fallthrough_probability;
aab92688 1966
1967 /* Update dominance info for the newly created then_bb; note that
1968 fallthru_bb's dominance info has already been updated by
1969 split_bock. */
1970 if (dom_info_available_p (CDI_DOMINATORS))
1971 set_immediate_dominator (CDI_DOMINATORS, then_bb, cond_bb);
1972
1973 *then_block = then_bb;
1974 *fallthrough_block = fallthru_bb;
1975 *iter = gsi_start_bb (fallthru_bb);
1976
1977 return gsi_last_bb (cond_bb);
1978}
1979
1ac3509e 1980/* Insert an if condition followed by a 'then block' right before the
1981 statement pointed to by ITER. The fallthrough block -- which is the
1982 else block of the condition as well as the destination of the
1983 outcoming edge of the 'then block' -- starts with the statement
1984 pointed to by ITER.
1985
eca932e6 1986 COND is the condition of the if.
1ac3509e 1987
1988 If THEN_MORE_LIKELY_P is true, the probability of the edge to the
1989 'then block' is higher than the probability of the edge to the
1990 fallthrough block.
1991
1992 Upon completion of the function, *THEN_BB is set to the newly
1993 inserted 'then block' and similarly, *FALLTHROUGH_BB is set to the
1994 fallthrough block.
1995
1996 *ITER is adjusted to still point to the same statement it was
1997 pointing to initially. */
1998
1999static void
1a91d914 2000insert_if_then_before_iter (gcond *cond,
1ac3509e 2001 gimple_stmt_iterator *iter,
2002 bool then_more_likely_p,
2003 basic_block *then_bb,
2004 basic_block *fallthrough_bb)
2005{
2006 gimple_stmt_iterator cond_insert_point =
2007 create_cond_insert_point (iter,
2008 /*before_p=*/true,
2009 then_more_likely_p,
e8d4d8a9 2010 /*create_then_fallthru_edge=*/true,
1ac3509e 2011 then_bb,
2012 fallthrough_bb);
2013 gsi_insert_after (&cond_insert_point, cond, GSI_NEW_STMT);
2014}
2015
629b6abc 2016/* Build (base_addr >> ASAN_SHADOW_SHIFT) + asan_shadow_offset ().
2017 If RETURN_ADDRESS is set to true, return memory location instread
2018 of a value in the shadow memory. */
86d3a572 2019
2020static tree
2021build_shadow_mem_access (gimple_stmt_iterator *gsi, location_t location,
629b6abc 2022 tree base_addr, tree shadow_ptr_type,
2023 bool return_address = false)
86d3a572 2024{
2025 tree t, uintptr_type = TREE_TYPE (base_addr);
2026 tree shadow_type = TREE_TYPE (shadow_ptr_type);
42acab1c 2027 gimple *g;
86d3a572 2028
2029 t = build_int_cst (uintptr_type, ASAN_SHADOW_SHIFT);
e9cf809e 2030 g = gimple_build_assign (make_ssa_name (uintptr_type), RSHIFT_EXPR,
2031 base_addr, t);
86d3a572 2032 gimple_set_location (g, location);
2033 gsi_insert_after (gsi, g, GSI_NEW_STMT);
2034
cf357977 2035 t = build_int_cst (uintptr_type, asan_shadow_offset ());
e9cf809e 2036 g = gimple_build_assign (make_ssa_name (uintptr_type), PLUS_EXPR,
2037 gimple_assign_lhs (g), t);
86d3a572 2038 gimple_set_location (g, location);
2039 gsi_insert_after (gsi, g, GSI_NEW_STMT);
2040
e9cf809e 2041 g = gimple_build_assign (make_ssa_name (shadow_ptr_type), NOP_EXPR,
2042 gimple_assign_lhs (g));
86d3a572 2043 gimple_set_location (g, location);
2044 gsi_insert_after (gsi, g, GSI_NEW_STMT);
2045
629b6abc 2046 if (!return_address)
2047 {
2048 t = build2 (MEM_REF, shadow_type, gimple_assign_lhs (g),
2049 build_int_cst (shadow_ptr_type, 0));
2050 g = gimple_build_assign (make_ssa_name (shadow_type), MEM_REF, t);
2051 gimple_set_location (g, location);
2052 gsi_insert_after (gsi, g, GSI_NEW_STMT);
2053 }
2054
86d3a572 2055 return gimple_assign_lhs (g);
2056}
2057
4f86f720 2058/* BASE can already be an SSA_NAME; in that case, do not create a
2059 new SSA_NAME for it. */
2060
2061static tree
2062maybe_create_ssa_name (location_t loc, tree base, gimple_stmt_iterator *iter,
2063 bool before_p)
2064{
2065 if (TREE_CODE (base) == SSA_NAME)
2066 return base;
42acab1c 2067 gimple *g = gimple_build_assign (make_ssa_name (TREE_TYPE (base)),
e9cf809e 2068 TREE_CODE (base), base);
4f86f720 2069 gimple_set_location (g, loc);
2070 if (before_p)
2071 gsi_insert_before (iter, g, GSI_SAME_STMT);
2072 else
2073 gsi_insert_after (iter, g, GSI_NEW_STMT);
2074 return gimple_assign_lhs (g);
2075}
2076
0a9f72cf 2077/* LEN can already have necessary size and precision;
2078 in that case, do not create a new variable. */
2079
2080tree
2081maybe_cast_to_ptrmode (location_t loc, tree len, gimple_stmt_iterator *iter,
2082 bool before_p)
2083{
2084 if (ptrofftype_p (len))
2085 return len;
42acab1c 2086 gimple *g = gimple_build_assign (make_ssa_name (pointer_sized_int_node),
e9cf809e 2087 NOP_EXPR, len);
0a9f72cf 2088 gimple_set_location (g, loc);
2089 if (before_p)
2090 gsi_insert_before (iter, g, GSI_SAME_STMT);
2091 else
2092 gsi_insert_after (iter, g, GSI_NEW_STMT);
2093 return gimple_assign_lhs (g);
2094}
2095
c91b0fff 2096/* Instrument the memory access instruction BASE. Insert new
1ac3509e 2097 statements before or after ITER.
c91b0fff 2098
2099 Note that the memory access represented by BASE can be either an
2100 SSA_NAME, or a non-SSA expression. LOCATION is the source code
2101 location. IS_STORE is TRUE for a store, FALSE for a load.
1ac3509e 2102 BEFORE_P is TRUE for inserting the instrumentation code before
4f86f720 2103 ITER, FALSE for inserting it after ITER. IS_SCALAR_ACCESS is TRUE
2104 for a scalar memory access and FALSE for memory region access.
2105 NON_ZERO_P is TRUE if memory region is guaranteed to have non-zero
2106 length. ALIGN tells alignment of accessed memory object.
2107
2108 START_INSTRUMENTED and END_INSTRUMENTED are TRUE if start/end of
2109 memory region have already been instrumented.
1ac3509e 2110
2111 If BEFORE_P is TRUE, *ITER is arranged to still point to the
2112 statement it was pointing to prior to calling this function,
2113 otherwise, it points to the statement logically following it. */
b92cccf4 2114
2115static void
ff326078 2116build_check_stmt (location_t loc, tree base, tree len,
4f86f720 2117 HOST_WIDE_INT size_in_bytes, gimple_stmt_iterator *iter,
ff326078 2118 bool is_non_zero_len, bool before_p, bool is_store,
f9acf11a 2119 bool is_scalar_access, unsigned int align = 0)
b92cccf4 2120{
4f86f720 2121 gimple_stmt_iterator gsi = *iter;
42acab1c 2122 gimple *g;
4f86f720 2123
ff326078 2124 gcc_assert (!(size_in_bytes > 0 && !is_non_zero_len));
4f86f720 2125
ff326078 2126 gsi = *iter;
2127
2128 base = unshare_expr (base);
2129 base = maybe_create_ssa_name (loc, base, &gsi, before_p);
2130
4f86f720 2131 if (len)
0a9f72cf 2132 {
2133 len = unshare_expr (len);
2134 len = maybe_cast_to_ptrmode (loc, len, iter, before_p);
2135 }
4f86f720 2136 else
2137 {
2138 gcc_assert (size_in_bytes != -1);
2139 len = build_int_cst (pointer_sized_int_node, size_in_bytes);
2140 }
2141
2142 if (size_in_bytes > 1)
93e990a3 2143 {
4f86f720 2144 if ((size_in_bytes & (size_in_bytes - 1)) != 0
2145 || size_in_bytes > 16)
ff326078 2146 is_scalar_access = false;
4f86f720 2147 else if (align && align < size_in_bytes * BITS_PER_UNIT)
2148 {
2149 /* On non-strict alignment targets, if
2150 16-byte access is just 8-byte aligned,
2151 this will result in misaligned shadow
2152 memory 2 byte load, but otherwise can
2153 be handled using one read. */
2154 if (size_in_bytes != 16
2155 || STRICT_ALIGNMENT
2156 || align < 8 * BITS_PER_UNIT)
ff326078 2157 is_scalar_access = false;
86d3a572 2158 }
5d5c682b 2159 }
b92cccf4 2160
ff326078 2161 HOST_WIDE_INT flags = 0;
2162 if (is_store)
2163 flags |= ASAN_CHECK_STORE;
2164 if (is_non_zero_len)
2165 flags |= ASAN_CHECK_NON_ZERO_LEN;
2166 if (is_scalar_access)
2167 flags |= ASAN_CHECK_SCALAR_ACCESS;
ff326078 2168
da81fb00 2169 g = gimple_build_call_internal (IFN_ASAN_CHECK, 4,
ff326078 2170 build_int_cst (integer_type_node, flags),
da81fb00 2171 base, len,
2172 build_int_cst (integer_type_node,
2173 align / BITS_PER_UNIT));
ff326078 2174 gimple_set_location (g, loc);
2175 if (before_p)
2176 gsi_insert_before (&gsi, g, GSI_SAME_STMT);
4f86f720 2177 else
2178 {
4f86f720 2179 gsi_insert_after (&gsi, g, GSI_NEW_STMT);
ff326078 2180 gsi_next (&gsi);
2181 *iter = gsi;
4f86f720 2182 }
b92cccf4 2183}
2184
2185/* If T represents a memory access, add instrumentation code before ITER.
2186 LOCATION is source code location.
1ac3509e 2187 IS_STORE is either TRUE (for a store) or FALSE (for a load). */
b92cccf4 2188
2189static void
2190instrument_derefs (gimple_stmt_iterator *iter, tree t,
c31c80df 2191 location_t location, bool is_store)
b92cccf4 2192{
bf2b7c22 2193 if (is_store && !ASAN_INSTRUMENT_WRITES)
2194 return;
2195 if (!is_store && !ASAN_INSTRUMENT_READS)
2196 return;
2197
b92cccf4 2198 tree type, base;
5d5c682b 2199 HOST_WIDE_INT size_in_bytes;
fcfbb129 2200 if (location == UNKNOWN_LOCATION)
2201 location = EXPR_LOCATION (t);
b92cccf4 2202
2203 type = TREE_TYPE (t);
b92cccf4 2204 switch (TREE_CODE (t))
2205 {
2206 case ARRAY_REF:
2207 case COMPONENT_REF:
2208 case INDIRECT_REF:
2209 case MEM_REF:
085f6ebf 2210 case VAR_DECL:
433da5c4 2211 case BIT_FIELD_REF:
b92cccf4 2212 break;
085f6ebf 2213 /* FALLTHRU */
b92cccf4 2214 default:
2215 return;
2216 }
5d5c682b 2217
2218 size_in_bytes = int_size_in_bytes (type);
86d3a572 2219 if (size_in_bytes <= 0)
5d5c682b 2220 return;
2221
81bc0f0f 2222 poly_int64 bitsize, bitpos;
5d5c682b 2223 tree offset;
3754d046 2224 machine_mode mode;
292237f3 2225 int unsignedp, reversep, volatilep = 0;
2226 tree inner = get_inner_reference (t, &bitsize, &bitpos, &offset, &mode,
b3b6e4b5 2227 &unsignedp, &reversep, &volatilep);
828ab337 2228
2229 if (TREE_CODE (t) == COMPONENT_REF
2230 && DECL_BIT_FIELD_REPRESENTATIVE (TREE_OPERAND (t, 1)) != NULL_TREE)
9ffeb5ce 2231 {
828ab337 2232 tree repr = DECL_BIT_FIELD_REPRESENTATIVE (TREE_OPERAND (t, 1));
2233 instrument_derefs (iter, build3 (COMPONENT_REF, TREE_TYPE (repr),
2234 TREE_OPERAND (t, 0), repr,
f4685159 2235 TREE_OPERAND (t, 2)),
2236 location, is_store);
9ffeb5ce 2237 return;
2238 }
828ab337 2239
81bc0f0f 2240 if (!multiple_p (bitpos, BITS_PER_UNIT)
2241 || maybe_ne (bitsize, size_in_bytes * BITS_PER_UNIT))
86d3a572 2242 return;
5d5c682b 2243
fa9cb955 2244 if (VAR_P (inner) && DECL_HARD_REGISTER (inner))
2245 return;
2246
81bc0f0f 2247 poly_int64 decl_size;
53e9c5c4 2248 if (VAR_P (inner)
085f6ebf 2249 && offset == NULL_TREE
085f6ebf 2250 && DECL_SIZE (inner)
81bc0f0f 2251 && poly_int_tree_p (DECL_SIZE (inner), &decl_size)
2252 && known_subrange_p (bitpos, bitsize, 0, decl_size))
085f6ebf 2253 {
2254 if (DECL_THREAD_LOCAL_P (inner))
2255 return;
a99c832c 2256 if (!ASAN_GLOBALS && is_global_var (inner))
2257 return;
085f6ebf 2258 if (!TREE_STATIC (inner))
2259 {
2260 /* Automatic vars in the current function will be always
2261 accessible. */
629b6abc 2262 if (decl_function_context (inner) == current_function_decl
2263 && (!asan_sanitize_use_after_scope ()
2264 || !TREE_ADDRESSABLE (inner)))
085f6ebf 2265 return;
2266 }
2267 /* Always instrument external vars, they might be dynamically
2268 initialized. */
2269 else if (!DECL_EXTERNAL (inner))
2270 {
2271 /* For static vars if they are known not to be dynamically
2272 initialized, they will be always accessible. */
97221fd7 2273 varpool_node *vnode = varpool_node::get (inner);
085f6ebf 2274 if (vnode && !vnode->dynamically_initialized)
2275 return;
2276 }
2277 }
2278
5d5c682b 2279 base = build_fold_addr_expr (t);
c31c80df 2280 if (!has_mem_ref_been_instrumented (base, size_in_bytes))
2281 {
4f86f720 2282 unsigned int align = get_object_alignment (t);
2283 build_check_stmt (location, base, NULL_TREE, size_in_bytes, iter,
ff326078 2284 /*is_non_zero_len*/size_in_bytes > 0, /*before_p=*/true,
4f86f720 2285 is_store, /*is_scalar_access*/true, align);
c31c80df 2286 update_mem_ref_hash_table (base, size_in_bytes);
2287 update_mem_ref_hash_table (t, size_in_bytes);
2288 }
2289
1ac3509e 2290}
2291
f9acf11a 2292/* Insert a memory reference into the hash table if access length
2293 can be determined in compile time. */
2294
2295static void
2296maybe_update_mem_ref_hash_table (tree base, tree len)
2297{
2298 if (!POINTER_TYPE_P (TREE_TYPE (base))
2299 || !INTEGRAL_TYPE_P (TREE_TYPE (len)))
2300 return;
2301
2302 HOST_WIDE_INT size_in_bytes = tree_fits_shwi_p (len) ? tree_to_shwi (len) : -1;
2303
2304 if (size_in_bytes != -1)
2305 update_mem_ref_hash_table (base, size_in_bytes);
2306}
2307
1ac3509e 2308/* Instrument an access to a contiguous memory region that starts at
2309 the address pointed to by BASE, over a length of LEN (expressed in
2310 the sizeof (*BASE) bytes). ITER points to the instruction before
2311 which the instrumentation instructions must be inserted. LOCATION
2312 is the source location that the instrumentation instructions must
2313 have. If IS_STORE is true, then the memory access is a store;
2314 otherwise, it's a load. */
2315
2316static void
2317instrument_mem_region_access (tree base, tree len,
2318 gimple_stmt_iterator *iter,
2319 location_t location, bool is_store)
2320{
94dbcbb6 2321 if (!POINTER_TYPE_P (TREE_TYPE (base))
2322 || !INTEGRAL_TYPE_P (TREE_TYPE (len))
2323 || integer_zerop (len))
1ac3509e 2324 return;
2325
4f86f720 2326 HOST_WIDE_INT size_in_bytes = tree_fits_shwi_p (len) ? tree_to_shwi (len) : -1;
c31c80df 2327
f9acf11a 2328 if ((size_in_bytes == -1)
2329 || !has_mem_ref_been_instrumented (base, size_in_bytes))
2330 {
2331 build_check_stmt (location, base, len, size_in_bytes, iter,
2332 /*is_non_zero_len*/size_in_bytes > 0, /*before_p*/true,
2333 is_store, /*is_scalar_access*/false, /*align*/0);
2334 }
d9dc05a1 2335
f9acf11a 2336 maybe_update_mem_ref_hash_table (base, len);
d9dc05a1 2337 *iter = gsi_for_stmt (gsi_stmt (*iter));
c31c80df 2338}
1ac3509e 2339
c31c80df 2340/* Instrument the call to a built-in memory access function that is
2341 pointed to by the iterator ITER.
1ac3509e 2342
c31c80df 2343 Upon completion, return TRUE iff *ITER has been advanced to the
2344 statement following the one it was originally pointing to. */
1ac3509e 2345
c31c80df 2346static bool
2347instrument_builtin_call (gimple_stmt_iterator *iter)
2348{
bf2b7c22 2349 if (!ASAN_MEMINTRIN)
2350 return false;
2351
c31c80df 2352 bool iter_advanced_p = false;
1a91d914 2353 gcall *call = as_a <gcall *> (gsi_stmt (*iter));
1ac3509e 2354
c31c80df 2355 gcc_checking_assert (gimple_call_builtin_p (call, BUILT_IN_NORMAL));
1ac3509e 2356
c31c80df 2357 location_t loc = gimple_location (call);
1ac3509e 2358
f9acf11a 2359 asan_mem_ref src0, src1, dest;
2360 asan_mem_ref_init (&src0, NULL, 1);
2361 asan_mem_ref_init (&src1, NULL, 1);
2362 asan_mem_ref_init (&dest, NULL, 1);
c31c80df 2363
f9acf11a 2364 tree src0_len = NULL_TREE, src1_len = NULL_TREE, dest_len = NULL_TREE;
2365 bool src0_is_store = false, src1_is_store = false, dest_is_store = false,
2366 dest_is_deref = false, intercepted_p = true;
c31c80df 2367
f9acf11a 2368 if (get_mem_refs_of_builtin_call (call,
2369 &src0, &src0_len, &src0_is_store,
2370 &src1, &src1_len, &src1_is_store,
2371 &dest, &dest_len, &dest_is_store,
d08919a7 2372 &dest_is_deref, &intercepted_p, iter))
f9acf11a 2373 {
2374 if (dest_is_deref)
c31c80df 2375 {
f9acf11a 2376 instrument_derefs (iter, dest.start, loc, dest_is_store);
2377 gsi_next (iter);
2378 iter_advanced_p = true;
2379 }
2380 else if (!intercepted_p
2381 && (src0_len || src1_len || dest_len))
2382 {
2383 if (src0.start != NULL_TREE)
2384 instrument_mem_region_access (src0.start, src0_len,
2385 iter, loc, /*is_store=*/false);
2386 if (src1.start != NULL_TREE)
2387 instrument_mem_region_access (src1.start, src1_len,
2388 iter, loc, /*is_store=*/false);
2389 if (dest.start != NULL_TREE)
2390 instrument_mem_region_access (dest.start, dest_len,
2391 iter, loc, /*is_store=*/true);
2392
2393 *iter = gsi_for_stmt (call);
2394 gsi_next (iter);
2395 iter_advanced_p = true;
2396 }
2397 else
2398 {
2399 if (src0.start != NULL_TREE)
2400 maybe_update_mem_ref_hash_table (src0.start, src0_len);
2401 if (src1.start != NULL_TREE)
2402 maybe_update_mem_ref_hash_table (src1.start, src1_len);
2403 if (dest.start != NULL_TREE)
2404 maybe_update_mem_ref_hash_table (dest.start, dest_len);
c31c80df 2405 }
1ac3509e 2406 }
c31c80df 2407 return iter_advanced_p;
1ac3509e 2408}
2409
2410/* Instrument the assignment statement ITER if it is subject to
c31c80df 2411 instrumentation. Return TRUE iff instrumentation actually
2412 happened. In that case, the iterator ITER is advanced to the next
2413 logical expression following the one initially pointed to by ITER,
2414 and the relevant memory reference that which access has been
2415 instrumented is added to the memory references hash table. */
1ac3509e 2416
c31c80df 2417static bool
2418maybe_instrument_assignment (gimple_stmt_iterator *iter)
1ac3509e 2419{
42acab1c 2420 gimple *s = gsi_stmt (*iter);
1ac3509e 2421
2422 gcc_assert (gimple_assign_single_p (s));
2423
c31c80df 2424 tree ref_expr = NULL_TREE;
2425 bool is_store, is_instrumented = false;
2426
38e9269e 2427 if (gimple_store_p (s))
c31c80df 2428 {
2429 ref_expr = gimple_assign_lhs (s);
2430 is_store = true;
2431 instrument_derefs (iter, ref_expr,
2432 gimple_location (s),
2433 is_store);
2434 is_instrumented = true;
2435 }
e815c2c5 2436
38e9269e 2437 if (gimple_assign_load_p (s))
c31c80df 2438 {
2439 ref_expr = gimple_assign_rhs1 (s);
2440 is_store = false;
2441 instrument_derefs (iter, ref_expr,
2442 gimple_location (s),
2443 is_store);
2444 is_instrumented = true;
2445 }
2446
2447 if (is_instrumented)
2448 gsi_next (iter);
2449
2450 return is_instrumented;
1ac3509e 2451}
2452
2453/* Instrument the function call pointed to by the iterator ITER, if it
2454 is subject to instrumentation. At the moment, the only function
2455 calls that are instrumented are some built-in functions that access
2456 memory. Look at instrument_builtin_call to learn more.
2457
2458 Upon completion return TRUE iff *ITER was advanced to the statement
2459 following the one it was originally pointing to. */
2460
2461static bool
2462maybe_instrument_call (gimple_stmt_iterator *iter)
2463{
42acab1c 2464 gimple *stmt = gsi_stmt (*iter);
c31c80df 2465 bool is_builtin = gimple_call_builtin_p (stmt, BUILT_IN_NORMAL);
2466
2467 if (is_builtin && instrument_builtin_call (iter))
494f4883 2468 return true;
c31c80df 2469
494f4883 2470 if (gimple_call_noreturn_p (stmt))
2471 {
2472 if (is_builtin)
2473 {
2474 tree callee = gimple_call_fndecl (stmt);
2475 switch (DECL_FUNCTION_CODE (callee))
2476 {
2477 case BUILT_IN_UNREACHABLE:
2478 case BUILT_IN_TRAP:
2479 /* Don't instrument these. */
2480 return false;
5213d6c9 2481 default:
2482 break;
494f4883 2483 }
2484 }
2485 tree decl = builtin_decl_implicit (BUILT_IN_ASAN_HANDLE_NO_RETURN);
42acab1c 2486 gimple *g = gimple_build_call (decl, 0);
494f4883 2487 gimple_set_location (g, gimple_location (stmt));
2488 gsi_insert_before (iter, g, GSI_SAME_STMT);
2489 }
774068a0 2490
fcfbb129 2491 bool instrumented = false;
774068a0 2492 if (gimple_store_p (stmt))
2493 {
2494 tree ref_expr = gimple_call_lhs (stmt);
2495 instrument_derefs (iter, ref_expr,
2496 gimple_location (stmt),
2497 /*is_store=*/true);
2498
fcfbb129 2499 instrumented = true;
774068a0 2500 }
2501
fcfbb129 2502 /* Walk through gimple_call arguments and check them id needed. */
2503 unsigned args_num = gimple_call_num_args (stmt);
2504 for (unsigned i = 0; i < args_num; ++i)
2505 {
2506 tree arg = gimple_call_arg (stmt, i);
2507 /* If ARG is not a non-aggregate register variable, compiler in general
2508 creates temporary for it and pass it as argument to gimple call.
2509 But in some cases, e.g. when we pass by value a small structure that
2510 fits to register, compiler can avoid extra overhead by pulling out
2511 these temporaries. In this case, we should check the argument. */
2512 if (!is_gimple_reg (arg) && !is_gimple_min_invariant (arg))
2513 {
2514 instrument_derefs (iter, arg,
2515 gimple_location (stmt),
2516 /*is_store=*/false);
2517 instrumented = true;
2518 }
2519 }
2520 if (instrumented)
2521 gsi_next (iter);
2522 return instrumented;
b92cccf4 2523}
2524
c31c80df 2525/* Walk each instruction of all basic block and instrument those that
2526 represent memory references: loads, stores, or function calls.
2527 In a given basic block, this function avoids instrumenting memory
2528 references that have already been instrumented. */
b92cccf4 2529
2530static void
2531transform_statements (void)
2532{
e8d4d8a9 2533 basic_block bb, last_bb = NULL;
b92cccf4 2534 gimple_stmt_iterator i;
fe672ac0 2535 int saved_last_basic_block = last_basic_block_for_fn (cfun);
b92cccf4 2536
fc00614f 2537 FOR_EACH_BB_FN (bb, cfun)
b92cccf4 2538 {
e8d4d8a9 2539 basic_block prev_bb = bb;
c31c80df 2540
b92cccf4 2541 if (bb->index >= saved_last_basic_block) continue;
e8d4d8a9 2542
2543 /* Flush the mem ref hash table, if current bb doesn't have
2544 exactly one predecessor, or if that predecessor (skipping
2545 over asan created basic blocks) isn't the last processed
2546 basic block. Thus we effectively flush on extended basic
2547 block boundaries. */
2548 while (single_pred_p (prev_bb))
2549 {
2550 prev_bb = single_pred (prev_bb);
2551 if (prev_bb->index < saved_last_basic_block)
2552 break;
2553 }
2554 if (prev_bb != last_bb)
2555 empty_mem_ref_hash_table ();
2556 last_bb = bb;
2557
1ac3509e 2558 for (i = gsi_start_bb (bb); !gsi_end_p (i);)
eca932e6 2559 {
42acab1c 2560 gimple *s = gsi_stmt (i);
1ac3509e 2561
c31c80df 2562 if (has_stmt_been_instrumented_p (s))
2563 gsi_next (&i);
2564 else if (gimple_assign_single_p (s)
e99409a5 2565 && !gimple_clobber_p (s)
c31c80df 2566 && maybe_instrument_assignment (&i))
2567 /* Nothing to do as maybe_instrument_assignment advanced
2568 the iterator I. */;
2569 else if (is_gimple_call (s) && maybe_instrument_call (&i))
2570 /* Nothing to do as maybe_instrument_call
2571 advanced the iterator I. */;
2572 else
1ac3509e 2573 {
c31c80df 2574 /* No instrumentation happened.
2575
e8d4d8a9 2576 If the current instruction is a function call that
2577 might free something, let's forget about the memory
2578 references that got instrumented. Otherwise we might
629b6abc 2579 miss some instrumentation opportunities. Do the same
2580 for a ASAN_MARK poisoning internal function. */
2581 if (is_gimple_call (s)
a30589d5 2582 && (!nonfreeing_call_p (s)
2583 || asan_mark_p (s, ASAN_MARK_POISON)))
c31c80df 2584 empty_mem_ref_hash_table ();
2585
2586 gsi_next (&i);
1ac3509e 2587 }
eca932e6 2588 }
b92cccf4 2589 }
c31c80df 2590 free_mem_ref_resources ();
b92cccf4 2591}
2592
085f6ebf 2593/* Build
2594 __asan_before_dynamic_init (module_name)
2595 or
2596 __asan_after_dynamic_init ()
2597 call. */
2598
2599tree
2600asan_dynamic_init_call (bool after_p)
2601{
bcab7035 2602 if (shadow_ptr_types[0] == NULL_TREE)
2603 asan_init_shadow_ptr_types ();
2604
085f6ebf 2605 tree fn = builtin_decl_implicit (after_p
2606 ? BUILT_IN_ASAN_AFTER_DYNAMIC_INIT
2607 : BUILT_IN_ASAN_BEFORE_DYNAMIC_INIT);
2608 tree module_name_cst = NULL_TREE;
2609 if (!after_p)
2610 {
2611 pretty_printer module_name_pp;
2612 pp_string (&module_name_pp, main_input_filename);
2613
085f6ebf 2614 module_name_cst = asan_pp_string (&module_name_pp);
2615 module_name_cst = fold_convert (const_ptr_type_node,
2616 module_name_cst);
2617 }
2618
2619 return build_call_expr (fn, after_p ? 0 : 1, module_name_cst);
2620}
2621
92fc5c48 2622/* Build
2623 struct __asan_global
2624 {
2625 const void *__beg;
2626 uptr __size;
2627 uptr __size_with_redzone;
2628 const void *__name;
1e80ce41 2629 const void *__module_name;
92fc5c48 2630 uptr __has_dynamic_init;
a9586c9c 2631 __asan_global_source_location *__location;
1350ad47 2632 char *__odr_indicator;
92fc5c48 2633 } type. */
2634
2635static tree
2636asan_global_struct (void)
2637{
47c3d0de 2638 static const char *field_names[]
92fc5c48 2639 = { "__beg", "__size", "__size_with_redzone",
47c3d0de 2640 "__name", "__module_name", "__has_dynamic_init", "__location",
2641 "__odr_indicator" };
2642 tree fields[ARRAY_SIZE (field_names)], ret;
2643 unsigned i;
92fc5c48 2644
2645 ret = make_node (RECORD_TYPE);
47c3d0de 2646 for (i = 0; i < ARRAY_SIZE (field_names); i++)
92fc5c48 2647 {
2648 fields[i]
2649 = build_decl (UNKNOWN_LOCATION, FIELD_DECL,
2650 get_identifier (field_names[i]),
2651 (i == 0 || i == 3) ? const_ptr_type_node
9e46467d 2652 : pointer_sized_int_node);
92fc5c48 2653 DECL_CONTEXT (fields[i]) = ret;
2654 if (i)
2655 DECL_CHAIN (fields[i - 1]) = fields[i];
2656 }
530273ed 2657 tree type_decl = build_decl (input_location, TYPE_DECL,
2658 get_identifier ("__asan_global"), ret);
2659 DECL_IGNORED_P (type_decl) = 1;
2660 DECL_ARTIFICIAL (type_decl) = 1;
92fc5c48 2661 TYPE_FIELDS (ret) = fields[0];
530273ed 2662 TYPE_NAME (ret) = type_decl;
2663 TYPE_STUB_DECL (ret) = type_decl;
92fc5c48 2664 layout_type (ret);
2665 return ret;
2666}
2667
47c3d0de 2668/* Create and return odr indicator symbol for DECL.
2669 TYPE is __asan_global struct type as returned by asan_global_struct. */
2670
2671static tree
2672create_odr_indicator (tree decl, tree type)
2673{
2674 char *name;
2675 tree uptr = TREE_TYPE (DECL_CHAIN (TYPE_FIELDS (type)));
2676 tree decl_name
2677 = (HAS_DECL_ASSEMBLER_NAME_P (decl) ? DECL_ASSEMBLER_NAME (decl)
2678 : DECL_NAME (decl));
2679 /* DECL_NAME theoretically might be NULL. Bail out with 0 in this case. */
2680 if (decl_name == NULL_TREE)
2681 return build_int_cst (uptr, 0);
377dc1bd 2682 const char *dname = IDENTIFIER_POINTER (decl_name);
2683 if (HAS_DECL_ASSEMBLER_NAME_P (decl))
2684 dname = targetm.strip_name_encoding (dname);
2685 size_t len = strlen (dname) + sizeof ("__odr_asan_");
47c3d0de 2686 name = XALLOCAVEC (char, len);
377dc1bd 2687 snprintf (name, len, "__odr_asan_%s", dname);
47c3d0de 2688#ifndef NO_DOT_IN_LABEL
2689 name[sizeof ("__odr_asan") - 1] = '.';
2690#elif !defined(NO_DOLLAR_IN_LABEL)
2691 name[sizeof ("__odr_asan") - 1] = '$';
2692#endif
2693 tree var = build_decl (UNKNOWN_LOCATION, VAR_DECL, get_identifier (name),
2694 char_type_node);
2695 TREE_ADDRESSABLE (var) = 1;
2696 TREE_READONLY (var) = 0;
2697 TREE_THIS_VOLATILE (var) = 1;
2698 DECL_GIMPLE_REG_P (var) = 0;
2699 DECL_ARTIFICIAL (var) = 1;
2700 DECL_IGNORED_P (var) = 1;
2701 TREE_STATIC (var) = 1;
2702 TREE_PUBLIC (var) = 1;
2703 DECL_VISIBILITY (var) = DECL_VISIBILITY (decl);
2704 DECL_VISIBILITY_SPECIFIED (var) = DECL_VISIBILITY_SPECIFIED (decl);
2705
2706 TREE_USED (var) = 1;
2707 tree ctor = build_constructor_va (TREE_TYPE (var), 1, NULL_TREE,
2708 build_int_cst (unsigned_type_node, 0));
2709 TREE_CONSTANT (ctor) = 1;
2710 TREE_STATIC (ctor) = 1;
2711 DECL_INITIAL (var) = ctor;
2712 DECL_ATTRIBUTES (var) = tree_cons (get_identifier ("asan odr indicator"),
2713 NULL, DECL_ATTRIBUTES (var));
2714 make_decl_rtl (var);
2715 varpool_node::finalize_decl (var);
2716 return fold_convert (uptr, build_fold_addr_expr (var));
2717}
2718
2719/* Return true if DECL, a global var, might be overridden and needs
2720 an additional odr indicator symbol. */
2721
2722static bool
2723asan_needs_odr_indicator_p (tree decl)
2724{
76af476d 2725 /* Don't emit ODR indicators for kernel because:
2726 a) Kernel is written in C thus doesn't need ODR indicators.
2727 b) Some kernel code may have assumptions about symbols containing specific
2728 patterns in their names. Since ODR indicators contain original names
2729 of symbols they are emitted for, these assumptions would be broken for
2730 ODR indicator symbols. */
2731 return (!(flag_sanitize & SANITIZE_KERNEL_ADDRESS)
2732 && !DECL_ARTIFICIAL (decl)
2733 && !DECL_WEAK (decl)
2734 && TREE_PUBLIC (decl));
47c3d0de 2735}
2736
92fc5c48 2737/* Append description of a single global DECL into vector V.
2738 TYPE is __asan_global struct type as returned by asan_global_struct. */
2739
2740static void
f1f41a6c 2741asan_add_global (tree decl, tree type, vec<constructor_elt, va_gc> *v)
92fc5c48 2742{
2743 tree init, uptr = TREE_TYPE (DECL_CHAIN (TYPE_FIELDS (type)));
2744 unsigned HOST_WIDE_INT size;
1e80ce41 2745 tree str_cst, module_name_cst, refdecl = decl;
f1f41a6c 2746 vec<constructor_elt, va_gc> *vinner = NULL;
92fc5c48 2747
1e80ce41 2748 pretty_printer asan_pp, module_name_pp;
92fc5c48 2749
92fc5c48 2750 if (DECL_NAME (decl))
a94db6b0 2751 pp_tree_identifier (&asan_pp, DECL_NAME (decl));
92fc5c48 2752 else
2753 pp_string (&asan_pp, "<unknown>");
b75d2c15 2754 str_cst = asan_pp_string (&asan_pp);
92fc5c48 2755
9b2d20e4 2756 pp_string (&module_name_pp, main_input_filename);
1e80ce41 2757 module_name_cst = asan_pp_string (&module_name_pp);
2758
92fc5c48 2759 if (asan_needs_local_alias (decl))
2760 {
2761 char buf[20];
f1f41a6c 2762 ASM_GENERATE_INTERNAL_LABEL (buf, "LASAN", vec_safe_length (v) + 1);
92fc5c48 2763 refdecl = build_decl (DECL_SOURCE_LOCATION (decl),
2764 VAR_DECL, get_identifier (buf), TREE_TYPE (decl));
2765 TREE_ADDRESSABLE (refdecl) = TREE_ADDRESSABLE (decl);
2766 TREE_READONLY (refdecl) = TREE_READONLY (decl);
2767 TREE_THIS_VOLATILE (refdecl) = TREE_THIS_VOLATILE (decl);
2768 DECL_GIMPLE_REG_P (refdecl) = DECL_GIMPLE_REG_P (decl);
2769 DECL_ARTIFICIAL (refdecl) = DECL_ARTIFICIAL (decl);
2770 DECL_IGNORED_P (refdecl) = DECL_IGNORED_P (decl);
2771 TREE_STATIC (refdecl) = 1;
2772 TREE_PUBLIC (refdecl) = 0;
2773 TREE_USED (refdecl) = 1;
2774 assemble_alias (refdecl, DECL_ASSEMBLER_NAME (decl));
2775 }
2776
47c3d0de 2777 tree odr_indicator_ptr
2778 = (asan_needs_odr_indicator_p (decl) ? create_odr_indicator (decl, type)
2779 : build_int_cst (uptr, 0));
92fc5c48 2780 CONSTRUCTOR_APPEND_ELT (vinner, NULL_TREE,
2781 fold_convert (const_ptr_type_node,
2782 build_fold_addr_expr (refdecl)));
6a0712d4 2783 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
92fc5c48 2784 CONSTRUCTOR_APPEND_ELT (vinner, NULL_TREE, build_int_cst (uptr, size));
2785 size += asan_red_zone_size (size);
2786 CONSTRUCTOR_APPEND_ELT (vinner, NULL_TREE, build_int_cst (uptr, size));
2787 CONSTRUCTOR_APPEND_ELT (vinner, NULL_TREE,
2788 fold_convert (const_ptr_type_node, str_cst));
1e80ce41 2789 CONSTRUCTOR_APPEND_ELT (vinner, NULL_TREE,
2790 fold_convert (const_ptr_type_node, module_name_cst));
97221fd7 2791 varpool_node *vnode = varpool_node::get (decl);
9b2d20e4 2792 int has_dynamic_init = 0;
2793 /* FIXME: Enable initialization order fiasco detection in LTO mode once
2794 proper fix for PR 79061 will be applied. */
2795 if (!in_lto_p)
2796 has_dynamic_init = vnode ? vnode->dynamically_initialized : 0;
085f6ebf 2797 CONSTRUCTOR_APPEND_ELT (vinner, NULL_TREE,
2798 build_int_cst (uptr, has_dynamic_init));
11d00a0b 2799 tree locptr = NULL_TREE;
2800 location_t loc = DECL_SOURCE_LOCATION (decl);
2801 expanded_location xloc = expand_location (loc);
2802 if (xloc.file != NULL)
2803 {
2804 static int lasanloccnt = 0;
2805 char buf[25];
2806 ASM_GENERATE_INTERNAL_LABEL (buf, "LASANLOC", ++lasanloccnt);
2807 tree var = build_decl (UNKNOWN_LOCATION, VAR_DECL, get_identifier (buf),
2808 ubsan_get_source_location_type ());
2809 TREE_STATIC (var) = 1;
2810 TREE_PUBLIC (var) = 0;
2811 DECL_ARTIFICIAL (var) = 1;
2812 DECL_IGNORED_P (var) = 1;
2813 pretty_printer filename_pp;
2814 pp_string (&filename_pp, xloc.file);
2815 tree str = asan_pp_string (&filename_pp);
2816 tree ctor = build_constructor_va (TREE_TYPE (var), 3,
2817 NULL_TREE, str, NULL_TREE,
2818 build_int_cst (unsigned_type_node,
2819 xloc.line), NULL_TREE,
2820 build_int_cst (unsigned_type_node,
2821 xloc.column));
2822 TREE_CONSTANT (ctor) = 1;
2823 TREE_STATIC (ctor) = 1;
2824 DECL_INITIAL (var) = ctor;
2825 varpool_node::finalize_decl (var);
2826 locptr = fold_convert (uptr, build_fold_addr_expr (var));
2827 }
2828 else
2829 locptr = build_int_cst (uptr, 0);
2830 CONSTRUCTOR_APPEND_ELT (vinner, NULL_TREE, locptr);
47c3d0de 2831 CONSTRUCTOR_APPEND_ELT (vinner, NULL_TREE, odr_indicator_ptr);
92fc5c48 2832 init = build_constructor (type, vinner);
2833 CONSTRUCTOR_APPEND_ELT (v, NULL_TREE, init);
2834}
2835
b45e34ed 2836/* Initialize sanitizer.def builtins if the FE hasn't initialized them. */
2837void
2838initialize_sanitizer_builtins (void)
2839{
2840 tree decl;
2841
2842 if (builtin_decl_implicit_p (BUILT_IN_ASAN_INIT))
2843 return;
2844
2845 tree BT_FN_VOID = build_function_type_list (void_type_node, NULL_TREE);
2846 tree BT_FN_VOID_PTR
2847 = build_function_type_list (void_type_node, ptr_type_node, NULL_TREE);
085f6ebf 2848 tree BT_FN_VOID_CONST_PTR
2849 = build_function_type_list (void_type_node, const_ptr_type_node, NULL_TREE);
2c4c3477 2850 tree BT_FN_VOID_PTR_PTR
2851 = build_function_type_list (void_type_node, ptr_type_node,
2852 ptr_type_node, NULL_TREE);
9e46467d 2853 tree BT_FN_VOID_PTR_PTR_PTR
2854 = build_function_type_list (void_type_node, ptr_type_node,
2855 ptr_type_node, ptr_type_node, NULL_TREE);
b45e34ed 2856 tree BT_FN_VOID_PTR_PTRMODE
2857 = build_function_type_list (void_type_node, ptr_type_node,
9e46467d 2858 pointer_sized_int_node, NULL_TREE);
83392e87 2859 tree BT_FN_VOID_INT
2860 = build_function_type_list (void_type_node, integer_type_node, NULL_TREE);
d14d27c6 2861 tree BT_FN_SIZE_CONST_PTR_INT
2862 = build_function_type_list (size_type_node, const_ptr_type_node,
2863 integer_type_node, NULL_TREE);
ccec7674 2864
2865 tree BT_FN_VOID_UINT8_UINT8
2866 = build_function_type_list (void_type_node, unsigned_char_type_node,
2867 unsigned_char_type_node, NULL_TREE);
2868 tree BT_FN_VOID_UINT16_UINT16
2869 = build_function_type_list (void_type_node, uint16_type_node,
2870 uint16_type_node, NULL_TREE);
2871 tree BT_FN_VOID_UINT32_UINT32
2872 = build_function_type_list (void_type_node, uint32_type_node,
2873 uint32_type_node, NULL_TREE);
2874 tree BT_FN_VOID_UINT64_UINT64
2875 = build_function_type_list (void_type_node, uint64_type_node,
2876 uint64_type_node, NULL_TREE);
2877 tree BT_FN_VOID_FLOAT_FLOAT
2878 = build_function_type_list (void_type_node, float_type_node,
2879 float_type_node, NULL_TREE);
2880 tree BT_FN_VOID_DOUBLE_DOUBLE
2881 = build_function_type_list (void_type_node, double_type_node,
2882 double_type_node, NULL_TREE);
2883 tree BT_FN_VOID_UINT64_PTR
2884 = build_function_type_list (void_type_node, uint64_type_node,
2885 ptr_type_node, NULL_TREE);
2886
83392e87 2887 tree BT_FN_BOOL_VPTR_PTR_IX_INT_INT[5];
2888 tree BT_FN_IX_CONST_VPTR_INT[5];
2889 tree BT_FN_IX_VPTR_IX_INT[5];
2890 tree BT_FN_VOID_VPTR_IX_INT[5];
2891 tree vptr
2892 = build_pointer_type (build_qualified_type (void_type_node,
2893 TYPE_QUAL_VOLATILE));
2894 tree cvptr
2895 = build_pointer_type (build_qualified_type (void_type_node,
2896 TYPE_QUAL_VOLATILE
2897 |TYPE_QUAL_CONST));
2898 tree boolt
2899 = lang_hooks.types.type_for_size (BOOL_TYPE_SIZE, 1);
2900 int i;
2901 for (i = 0; i < 5; i++)
2902 {
2903 tree ix = build_nonstandard_integer_type (BITS_PER_UNIT * (1 << i), 1);
2904 BT_FN_BOOL_VPTR_PTR_IX_INT_INT[i]
2905 = build_function_type_list (boolt, vptr, ptr_type_node, ix,
2906 integer_type_node, integer_type_node,
2907 NULL_TREE);
2908 BT_FN_IX_CONST_VPTR_INT[i]
2909 = build_function_type_list (ix, cvptr, integer_type_node, NULL_TREE);
2910 BT_FN_IX_VPTR_IX_INT[i]
2911 = build_function_type_list (ix, vptr, ix, integer_type_node,
2912 NULL_TREE);
2913 BT_FN_VOID_VPTR_IX_INT[i]
2914 = build_function_type_list (void_type_node, vptr, ix,
2915 integer_type_node, NULL_TREE);
2916 }
2917#define BT_FN_BOOL_VPTR_PTR_I1_INT_INT BT_FN_BOOL_VPTR_PTR_IX_INT_INT[0]
2918#define BT_FN_I1_CONST_VPTR_INT BT_FN_IX_CONST_VPTR_INT[0]
2919#define BT_FN_I1_VPTR_I1_INT BT_FN_IX_VPTR_IX_INT[0]
2920#define BT_FN_VOID_VPTR_I1_INT BT_FN_VOID_VPTR_IX_INT[0]
2921#define BT_FN_BOOL_VPTR_PTR_I2_INT_INT BT_FN_BOOL_VPTR_PTR_IX_INT_INT[1]
2922#define BT_FN_I2_CONST_VPTR_INT BT_FN_IX_CONST_VPTR_INT[1]
2923#define BT_FN_I2_VPTR_I2_INT BT_FN_IX_VPTR_IX_INT[1]
2924#define BT_FN_VOID_VPTR_I2_INT BT_FN_VOID_VPTR_IX_INT[1]
2925#define BT_FN_BOOL_VPTR_PTR_I4_INT_INT BT_FN_BOOL_VPTR_PTR_IX_INT_INT[2]
2926#define BT_FN_I4_CONST_VPTR_INT BT_FN_IX_CONST_VPTR_INT[2]
2927#define BT_FN_I4_VPTR_I4_INT BT_FN_IX_VPTR_IX_INT[2]
2928#define BT_FN_VOID_VPTR_I4_INT BT_FN_VOID_VPTR_IX_INT[2]
2929#define BT_FN_BOOL_VPTR_PTR_I8_INT_INT BT_FN_BOOL_VPTR_PTR_IX_INT_INT[3]
2930#define BT_FN_I8_CONST_VPTR_INT BT_FN_IX_CONST_VPTR_INT[3]
2931#define BT_FN_I8_VPTR_I8_INT BT_FN_IX_VPTR_IX_INT[3]
2932#define BT_FN_VOID_VPTR_I8_INT BT_FN_VOID_VPTR_IX_INT[3]
2933#define BT_FN_BOOL_VPTR_PTR_I16_INT_INT BT_FN_BOOL_VPTR_PTR_IX_INT_INT[4]
2934#define BT_FN_I16_CONST_VPTR_INT BT_FN_IX_CONST_VPTR_INT[4]
2935#define BT_FN_I16_VPTR_I16_INT BT_FN_IX_VPTR_IX_INT[4]
2936#define BT_FN_VOID_VPTR_I16_INT BT_FN_VOID_VPTR_IX_INT[4]
b45e34ed 2937#undef ATTR_NOTHROW_LEAF_LIST
2938#define ATTR_NOTHROW_LEAF_LIST ECF_NOTHROW | ECF_LEAF
c2901651 2939#undef ATTR_TMPURE_NOTHROW_LEAF_LIST
2940#define ATTR_TMPURE_NOTHROW_LEAF_LIST ECF_TM_PURE | ATTR_NOTHROW_LEAF_LIST
b45e34ed 2941#undef ATTR_NORETURN_NOTHROW_LEAF_LIST
2942#define ATTR_NORETURN_NOTHROW_LEAF_LIST ECF_NORETURN | ATTR_NOTHROW_LEAF_LIST
f6b540af 2943#undef ATTR_CONST_NORETURN_NOTHROW_LEAF_LIST
2944#define ATTR_CONST_NORETURN_NOTHROW_LEAF_LIST \
2945 ECF_CONST | ATTR_NORETURN_NOTHROW_LEAF_LIST
c2901651 2946#undef ATTR_TMPURE_NORETURN_NOTHROW_LEAF_LIST
2947#define ATTR_TMPURE_NORETURN_NOTHROW_LEAF_LIST \
2948 ECF_TM_PURE | ATTR_NORETURN_NOTHROW_LEAF_LIST
9e46467d 2949#undef ATTR_COLD_NOTHROW_LEAF_LIST
2950#define ATTR_COLD_NOTHROW_LEAF_LIST \
2951 /* ECF_COLD missing */ ATTR_NOTHROW_LEAF_LIST
2952#undef ATTR_COLD_NORETURN_NOTHROW_LEAF_LIST
2953#define ATTR_COLD_NORETURN_NOTHROW_LEAF_LIST \
2954 /* ECF_COLD missing */ ATTR_NORETURN_NOTHROW_LEAF_LIST
f6b540af 2955#undef ATTR_COLD_CONST_NORETURN_NOTHROW_LEAF_LIST
2956#define ATTR_COLD_CONST_NORETURN_NOTHROW_LEAF_LIST \
2957 /* ECF_COLD missing */ ATTR_CONST_NORETURN_NOTHROW_LEAF_LIST
d14d27c6 2958#undef ATTR_PURE_NOTHROW_LEAF_LIST
2959#define ATTR_PURE_NOTHROW_LEAF_LIST ECF_PURE | ATTR_NOTHROW_LEAF_LIST
ee49ca6a 2960#undef DEF_BUILTIN_STUB
2961#define DEF_BUILTIN_STUB(ENUM, NAME)
2467912c 2962#undef DEF_SANITIZER_BUILTIN_1
2963#define DEF_SANITIZER_BUILTIN_1(ENUM, NAME, TYPE, ATTRS) \
cf5531b5 2964 do { \
2965 decl = add_builtin_function ("__builtin_" NAME, TYPE, ENUM, \
2966 BUILT_IN_NORMAL, NAME, NULL_TREE); \
2967 set_call_expr_flags (decl, ATTRS); \
2968 set_builtin_decl (ENUM, decl, true); \
2467912c 2969 } while (0)
2970#undef DEF_SANITIZER_BUILTIN
2971#define DEF_SANITIZER_BUILTIN(ENUM, NAME, TYPE, ATTRS) \
2972 DEF_SANITIZER_BUILTIN_1 (ENUM, NAME, TYPE, ATTRS);
b45e34ed 2973
2974#include "sanitizer.def"
2975
d14d27c6 2976 /* -fsanitize=object-size uses __builtin_object_size, but that might
2977 not be available for e.g. Fortran at this point. We use
2978 DEF_SANITIZER_BUILTIN here only as a convenience macro. */
2979 if ((flag_sanitize & SANITIZE_OBJECT_SIZE)
2980 && !builtin_decl_implicit_p (BUILT_IN_OBJECT_SIZE))
2467912c 2981 DEF_SANITIZER_BUILTIN_1 (BUILT_IN_OBJECT_SIZE, "object_size",
2982 BT_FN_SIZE_CONST_PTR_INT,
2983 ATTR_PURE_NOTHROW_LEAF_LIST);
d14d27c6 2984
2467912c 2985#undef DEF_SANITIZER_BUILTIN_1
b45e34ed 2986#undef DEF_SANITIZER_BUILTIN
ee49ca6a 2987#undef DEF_BUILTIN_STUB
b45e34ed 2988}
2989
55b58027 2990/* Called via htab_traverse. Count number of emitted
2991 STRING_CSTs in the constant hash table. */
2992
2ef51f0e 2993int
2994count_string_csts (constant_descriptor_tree **slot,
2995 unsigned HOST_WIDE_INT *data)
55b58027 2996{
2ef51f0e 2997 struct constant_descriptor_tree *desc = *slot;
55b58027 2998 if (TREE_CODE (desc->value) == STRING_CST
2999 && TREE_ASM_WRITTEN (desc->value)
3000 && asan_protect_global (desc->value))
2ef51f0e 3001 ++*data;
55b58027 3002 return 1;
3003}
3004
3005/* Helper structure to pass two parameters to
3006 add_string_csts. */
3007
3008struct asan_add_string_csts_data
3009{
3010 tree type;
3011 vec<constructor_elt, va_gc> *v;
3012};
3013
2ef51f0e 3014/* Called via hash_table::traverse. Call asan_add_global
55b58027 3015 on emitted STRING_CSTs from the constant hash table. */
3016
2ef51f0e 3017int
3018add_string_csts (constant_descriptor_tree **slot,
3019 asan_add_string_csts_data *aascd)
55b58027 3020{
2ef51f0e 3021 struct constant_descriptor_tree *desc = *slot;
55b58027 3022 if (TREE_CODE (desc->value) == STRING_CST
3023 && TREE_ASM_WRITTEN (desc->value)
3024 && asan_protect_global (desc->value))
3025 {
55b58027 3026 asan_add_global (SYMBOL_REF_DECL (XEXP (desc->rtl, 0)),
3027 aascd->type, aascd->v);
3028 }
3029 return 1;
3030}
3031
92fc5c48 3032/* Needs to be GTY(()), because cgraph_build_static_cdtor may
3033 invoke ggc_collect. */
3034static GTY(()) tree asan_ctor_statements;
3035
b92cccf4 3036/* Module-level instrumentation.
1e80ce41 3037 - Insert __asan_init_vN() into the list of CTORs.
b92cccf4 3038 - TODO: insert redzones around globals.
3039 */
3040
3041void
3042asan_finish_file (void)
3043{
098f44bc 3044 varpool_node *vnode;
92fc5c48 3045 unsigned HOST_WIDE_INT gcount = 0;
3046
55b58027 3047 if (shadow_ptr_types[0] == NULL_TREE)
3048 asan_init_shadow_ptr_types ();
3049 /* Avoid instrumenting code in the asan ctors/dtors.
3050 We don't need to insert padding after the description strings,
3051 nor after .LASAN* array. */
9e46467d 3052 flag_sanitize &= ~SANITIZE_ADDRESS;
b45e34ed 3053
aa1dfc5f 3054 /* For user-space we want asan constructors to run first.
3055 Linux kernel does not support priorities other than default, and the only
3056 other user of constructors is coverage. So we run with the default
3057 priority. */
3058 int priority = flag_sanitize & SANITIZE_USER_ADDRESS
3059 ? MAX_RESERVED_INIT_PRIORITY - 1 : DEFAULT_INIT_PRIORITY;
3060
647918a4 3061 if (flag_sanitize & SANITIZE_USER_ADDRESS)
3062 {
3063 tree fn = builtin_decl_implicit (BUILT_IN_ASAN_INIT);
3064 append_to_statement_list (build_call_expr (fn, 0), &asan_ctor_statements);
7966ce00 3065 fn = builtin_decl_implicit (BUILT_IN_ASAN_VERSION_MISMATCH_CHECK);
3066 append_to_statement_list (build_call_expr (fn, 0), &asan_ctor_statements);
647918a4 3067 }
92fc5c48 3068 FOR_EACH_DEFINED_VARIABLE (vnode)
02774f2d 3069 if (TREE_ASM_WRITTEN (vnode->decl)
3070 && asan_protect_global (vnode->decl))
92fc5c48 3071 ++gcount;
2ef51f0e 3072 hash_table<tree_descriptor_hasher> *const_desc_htab = constant_pool_htab ();
3073 const_desc_htab->traverse<unsigned HOST_WIDE_INT *, count_string_csts>
3074 (&gcount);
92fc5c48 3075 if (gcount)
3076 {
b45e34ed 3077 tree type = asan_global_struct (), var, ctor;
92fc5c48 3078 tree dtor_statements = NULL_TREE;
f1f41a6c 3079 vec<constructor_elt, va_gc> *v;
92fc5c48 3080 char buf[20];
3081
3082 type = build_array_type_nelts (type, gcount);
3083 ASM_GENERATE_INTERNAL_LABEL (buf, "LASAN", 0);
3084 var = build_decl (UNKNOWN_LOCATION, VAR_DECL, get_identifier (buf),
3085 type);
3086 TREE_STATIC (var) = 1;
3087 TREE_PUBLIC (var) = 0;
3088 DECL_ARTIFICIAL (var) = 1;
3089 DECL_IGNORED_P (var) = 1;
f1f41a6c 3090 vec_alloc (v, gcount);
92fc5c48 3091 FOR_EACH_DEFINED_VARIABLE (vnode)
02774f2d 3092 if (TREE_ASM_WRITTEN (vnode->decl)
3093 && asan_protect_global (vnode->decl))
3094 asan_add_global (vnode->decl, TREE_TYPE (type), v);
55b58027 3095 struct asan_add_string_csts_data aascd;
3096 aascd.type = TREE_TYPE (type);
3097 aascd.v = v;
2ef51f0e 3098 const_desc_htab->traverse<asan_add_string_csts_data *, add_string_csts>
3099 (&aascd);
92fc5c48 3100 ctor = build_constructor (type, v);
3101 TREE_CONSTANT (ctor) = 1;
3102 TREE_STATIC (ctor) = 1;
3103 DECL_INITIAL (var) = ctor;
1c59997f 3104 SET_DECL_ALIGN (var, MAX (DECL_ALIGN (var),
3105 ASAN_SHADOW_GRANULARITY * BITS_PER_UNIT));
3106
97221fd7 3107 varpool_node::finalize_decl (var);
92fc5c48 3108
647918a4 3109 tree fn = builtin_decl_implicit (BUILT_IN_ASAN_REGISTER_GLOBALS);
9e46467d 3110 tree gcount_tree = build_int_cst (pointer_sized_int_node, gcount);
b45e34ed 3111 append_to_statement_list (build_call_expr (fn, 2,
92fc5c48 3112 build_fold_addr_expr (var),
9e46467d 3113 gcount_tree),
92fc5c48 3114 &asan_ctor_statements);
3115
b45e34ed 3116 fn = builtin_decl_implicit (BUILT_IN_ASAN_UNREGISTER_GLOBALS);
3117 append_to_statement_list (build_call_expr (fn, 2,
92fc5c48 3118 build_fold_addr_expr (var),
9e46467d 3119 gcount_tree),
92fc5c48 3120 &dtor_statements);
aa1dfc5f 3121 cgraph_build_static_cdtor ('D', dtor_statements, priority);
92fc5c48 3122 }
647918a4 3123 if (asan_ctor_statements)
aa1dfc5f 3124 cgraph_build_static_cdtor ('I', asan_ctor_statements, priority);
9e46467d 3125 flag_sanitize |= SANITIZE_ADDRESS;
5d5c682b 3126}
3127
629b6abc 3128/* Poison or unpoison (depending on IS_CLOBBER variable) shadow memory based
3129 on SHADOW address. Newly added statements will be added to ITER with
3130 given location LOC. We mark SIZE bytes in shadow memory, where
3131 LAST_CHUNK_SIZE is greater than zero in situation where we are at the
3132 end of a variable. */
3133
3134static void
3135asan_store_shadow_bytes (gimple_stmt_iterator *iter, location_t loc,
3136 tree shadow,
3137 unsigned HOST_WIDE_INT base_addr_offset,
3138 bool is_clobber, unsigned size,
3139 unsigned last_chunk_size)
3140{
3141 tree shadow_ptr_type;
3142
3143 switch (size)
3144 {
3145 case 1:
3146 shadow_ptr_type = shadow_ptr_types[0];
3147 break;
3148 case 2:
3149 shadow_ptr_type = shadow_ptr_types[1];
3150 break;
3151 case 4:
3152 shadow_ptr_type = shadow_ptr_types[2];
3153 break;
3154 default:
3155 gcc_unreachable ();
3156 }
3157
3158 unsigned char c = (char) is_clobber ? ASAN_STACK_MAGIC_USE_AFTER_SCOPE : 0;
3159 unsigned HOST_WIDE_INT val = 0;
6dc83378 3160 unsigned last_pos = size;
3161 if (last_chunk_size && !is_clobber)
3162 last_pos = BYTES_BIG_ENDIAN ? 0 : size - 1;
629b6abc 3163 for (unsigned i = 0; i < size; ++i)
3164 {
3165 unsigned char shadow_c = c;
6dc83378 3166 if (i == last_pos)
629b6abc 3167 shadow_c = last_chunk_size;
3168 val |= (unsigned HOST_WIDE_INT) shadow_c << (BITS_PER_UNIT * i);
3169 }
3170
3171 /* Handle last chunk in unpoisoning. */
3172 tree magic = build_int_cst (TREE_TYPE (shadow_ptr_type), val);
3173
3174 tree dest = build2 (MEM_REF, TREE_TYPE (shadow_ptr_type), shadow,
3175 build_int_cst (shadow_ptr_type, base_addr_offset));
3176
3177 gimple *g = gimple_build_assign (dest, magic);
3178 gimple_set_location (g, loc);
3179 gsi_insert_after (iter, g, GSI_NEW_STMT);
3180}
3181
3182/* Expand the ASAN_MARK builtins. */
3183
3184bool
3185asan_expand_mark_ifn (gimple_stmt_iterator *iter)
3186{
3187 gimple *g = gsi_stmt (*iter);
3188 location_t loc = gimple_location (g);
a30589d5 3189 HOST_WIDE_INT flag = tree_to_shwi (gimple_call_arg (g, 0));
3190 bool is_poison = ((asan_mark_flags)flag) == ASAN_MARK_POISON;
629b6abc 3191
3192 tree base = gimple_call_arg (g, 1);
3193 gcc_checking_assert (TREE_CODE (base) == ADDR_EXPR);
3194 tree decl = TREE_OPERAND (base, 0);
9b51ac50 3195
3196 /* For a nested function, we can have: ASAN_MARK (2, &FRAME.2.fp_input, 4) */
3197 if (TREE_CODE (decl) == COMPONENT_REF
3198 && DECL_NONLOCAL_FRAME (TREE_OPERAND (decl, 0)))
3199 decl = TREE_OPERAND (decl, 0);
3200
629b6abc 3201 gcc_checking_assert (TREE_CODE (decl) == VAR_DECL);
355c1762 3202
3203 if (is_poison)
3204 {
3205 if (asan_handled_variables == NULL)
3206 asan_handled_variables = new hash_set<tree> (16);
3207 asan_handled_variables->add (decl);
3208 }
629b6abc 3209 tree len = gimple_call_arg (g, 2);
3210
3211 gcc_assert (tree_fits_shwi_p (len));
3212 unsigned HOST_WIDE_INT size_in_bytes = tree_to_shwi (len);
3213 gcc_assert (size_in_bytes);
3214
3215 g = gimple_build_assign (make_ssa_name (pointer_sized_int_node),
3216 NOP_EXPR, base);
3217 gimple_set_location (g, loc);
3218 gsi_replace (iter, g, false);
3219 tree base_addr = gimple_assign_lhs (g);
3220
3221 /* Generate direct emission if size_in_bytes is small. */
3222 if (size_in_bytes <= ASAN_PARAM_USE_AFTER_SCOPE_DIRECT_EMISSION_THRESHOLD)
3223 {
3f00a89f 3224 const unsigned HOST_WIDE_INT shadow_size
3225 = shadow_mem_size (size_in_bytes);
3226 const unsigned int shadow_align
3227 = (get_pointer_alignment (base) / BITS_PER_UNIT) >> ASAN_SHADOW_SHIFT;
629b6abc 3228
3229 tree shadow = build_shadow_mem_access (iter, loc, base_addr,
3230 shadow_ptr_types[0], true);
3231
3232 for (unsigned HOST_WIDE_INT offset = 0; offset < shadow_size;)
3233 {
3234 unsigned size = 1;
3f00a89f 3235 if (shadow_size - offset >= 4
3236 && (!STRICT_ALIGNMENT || shadow_align >= 4))
629b6abc 3237 size = 4;
3f00a89f 3238 else if (shadow_size - offset >= 2
3239 && (!STRICT_ALIGNMENT || shadow_align >= 2))
629b6abc 3240 size = 2;
3241
3242 unsigned HOST_WIDE_INT last_chunk_size = 0;
3243 unsigned HOST_WIDE_INT s = (offset + size) * ASAN_SHADOW_GRANULARITY;
3244 if (s > size_in_bytes)
3245 last_chunk_size = ASAN_SHADOW_GRANULARITY - (s - size_in_bytes);
3246
a30589d5 3247 asan_store_shadow_bytes (iter, loc, shadow, offset, is_poison,
629b6abc 3248 size, last_chunk_size);
3249 offset += size;
3250 }
3251 }
3252 else
3253 {
3254 g = gimple_build_assign (make_ssa_name (pointer_sized_int_node),
3255 NOP_EXPR, len);
3256 gimple_set_location (g, loc);
3257 gsi_insert_before (iter, g, GSI_SAME_STMT);
3258 tree sz_arg = gimple_assign_lhs (g);
3259
c6c892c5 3260 tree fun
3261 = builtin_decl_implicit (is_poison ? BUILT_IN_ASAN_POISON_STACK_MEMORY
3262 : BUILT_IN_ASAN_UNPOISON_STACK_MEMORY);
629b6abc 3263 g = gimple_build_call (fun, 2, base_addr, sz_arg);
3264 gimple_set_location (g, loc);
3265 gsi_insert_after (iter, g, GSI_NEW_STMT);
3266 }
3267
3268 return false;
3269}
3270
ff326078 3271/* Expand the ASAN_{LOAD,STORE} builtins. */
3272
6b5813f5 3273bool
ff326078 3274asan_expand_check_ifn (gimple_stmt_iterator *iter, bool use_calls)
3275{
42acab1c 3276 gimple *g = gsi_stmt (*iter);
ff326078 3277 location_t loc = gimple_location (g);
21017ecb 3278 bool recover_p;
3279 if (flag_sanitize & SANITIZE_USER_ADDRESS)
3280 recover_p = (flag_sanitize_recover & SANITIZE_USER_ADDRESS) != 0;
3281 else
3282 recover_p = (flag_sanitize_recover & SANITIZE_KERNEL_ADDRESS) != 0;
f4d482a6 3283
ff326078 3284 HOST_WIDE_INT flags = tree_to_shwi (gimple_call_arg (g, 0));
3285 gcc_assert (flags < ASAN_CHECK_LAST);
3286 bool is_scalar_access = (flags & ASAN_CHECK_SCALAR_ACCESS) != 0;
3287 bool is_store = (flags & ASAN_CHECK_STORE) != 0;
3288 bool is_non_zero_len = (flags & ASAN_CHECK_NON_ZERO_LEN) != 0;
ff326078 3289
3290 tree base = gimple_call_arg (g, 1);
3291 tree len = gimple_call_arg (g, 2);
da81fb00 3292 HOST_WIDE_INT align = tree_to_shwi (gimple_call_arg (g, 3));
ff326078 3293
3294 HOST_WIDE_INT size_in_bytes
3295 = is_scalar_access && tree_fits_shwi_p (len) ? tree_to_shwi (len) : -1;
3296
3297 if (use_calls)
3298 {
3299 /* Instrument using callbacks. */
42acab1c 3300 gimple *g = gimple_build_assign (make_ssa_name (pointer_sized_int_node),
e9cf809e 3301 NOP_EXPR, base);
ff326078 3302 gimple_set_location (g, loc);
3303 gsi_insert_before (iter, g, GSI_SAME_STMT);
3304 tree base_addr = gimple_assign_lhs (g);
3305
3306 int nargs;
f4d482a6 3307 tree fun = check_func (is_store, recover_p, size_in_bytes, &nargs);
ff326078 3308 if (nargs == 1)
3309 g = gimple_build_call (fun, 1, base_addr);
3310 else
3311 {
3312 gcc_assert (nargs == 2);
e9cf809e 3313 g = gimple_build_assign (make_ssa_name (pointer_sized_int_node),
3314 NOP_EXPR, len);
ff326078 3315 gimple_set_location (g, loc);
3316 gsi_insert_before (iter, g, GSI_SAME_STMT);
3317 tree sz_arg = gimple_assign_lhs (g);
3318 g = gimple_build_call (fun, nargs, base_addr, sz_arg);
3319 }
3320 gimple_set_location (g, loc);
3321 gsi_replace (iter, g, false);
3322 return false;
3323 }
3324
3325 HOST_WIDE_INT real_size_in_bytes = size_in_bytes == -1 ? 1 : size_in_bytes;
3326
ff326078 3327 tree shadow_ptr_type = shadow_ptr_types[real_size_in_bytes == 16 ? 1 : 0];
3328 tree shadow_type = TREE_TYPE (shadow_ptr_type);
3329
3330 gimple_stmt_iterator gsi = *iter;
3331
3332 if (!is_non_zero_len)
3333 {
3334 /* So, the length of the memory area to asan-protect is
3335 non-constant. Let's guard the generated instrumentation code
3336 like:
3337
3338 if (len != 0)
3339 {
3340 //asan instrumentation code goes here.
3341 }
3342 // falltrough instructions, starting with *ITER. */
3343
3344 g = gimple_build_cond (NE_EXPR,
3345 len,
3346 build_int_cst (TREE_TYPE (len), 0),
3347 NULL_TREE, NULL_TREE);
3348 gimple_set_location (g, loc);
3349
3350 basic_block then_bb, fallthrough_bb;
1a91d914 3351 insert_if_then_before_iter (as_a <gcond *> (g), iter,
3352 /*then_more_likely_p=*/true,
3353 &then_bb, &fallthrough_bb);
ff326078 3354 /* Note that fallthrough_bb starts with the statement that was
3355 pointed to by ITER. */
3356
3357 /* The 'then block' of the 'if (len != 0) condition is where
3358 we'll generate the asan instrumentation code now. */
3359 gsi = gsi_last_bb (then_bb);
3360 }
3361
3362 /* Get an iterator on the point where we can add the condition
3363 statement for the instrumentation. */
3364 basic_block then_bb, else_bb;
3365 gsi = create_cond_insert_point (&gsi, /*before_p*/false,
3366 /*then_more_likely_p=*/false,
f4d482a6 3367 /*create_then_fallthru_edge*/recover_p,
ff326078 3368 &then_bb,
3369 &else_bb);
3370
e9cf809e 3371 g = gimple_build_assign (make_ssa_name (pointer_sized_int_node),
3372 NOP_EXPR, base);
ff326078 3373 gimple_set_location (g, loc);
3374 gsi_insert_before (&gsi, g, GSI_NEW_STMT);
3375 tree base_addr = gimple_assign_lhs (g);
3376
3377 tree t = NULL_TREE;
3378 if (real_size_in_bytes >= 8)
3379 {
3380 tree shadow = build_shadow_mem_access (&gsi, loc, base_addr,
3381 shadow_ptr_type);
3382 t = shadow;
3383 }
3384 else
3385 {
3386 /* Slow path for 1, 2 and 4 byte accesses. */
f9acf11a 3387 /* Test (shadow != 0)
3388 & ((base_addr & 7) + (real_size_in_bytes - 1)) >= shadow). */
3389 tree shadow = build_shadow_mem_access (&gsi, loc, base_addr,
3390 shadow_ptr_type);
42acab1c 3391 gimple *shadow_test = build_assign (NE_EXPR, shadow, 0);
f9acf11a 3392 gimple_seq seq = NULL;
3393 gimple_seq_add_stmt (&seq, shadow_test);
3394 /* Aligned (>= 8 bytes) can test just
3395 (real_size_in_bytes - 1 >= shadow), as base_addr & 7 is known
3396 to be 0. */
3397 if (align < 8)
ff326078 3398 {
f9acf11a 3399 gimple_seq_add_stmt (&seq, build_assign (BIT_AND_EXPR,
3400 base_addr, 7));
3401 gimple_seq_add_stmt (&seq,
3402 build_type_cast (shadow_type,
3403 gimple_seq_last (seq)));
3404 if (real_size_in_bytes > 1)
3405 gimple_seq_add_stmt (&seq,
3406 build_assign (PLUS_EXPR,
3407 gimple_seq_last (seq),
3408 real_size_in_bytes - 1));
3409 t = gimple_assign_lhs (gimple_seq_last_stmt (seq));
ff326078 3410 }
f9acf11a 3411 else
3412 t = build_int_cst (shadow_type, real_size_in_bytes - 1);
3413 gimple_seq_add_stmt (&seq, build_assign (GE_EXPR, t, shadow));
3414 gimple_seq_add_stmt (&seq, build_assign (BIT_AND_EXPR, shadow_test,
3415 gimple_seq_last (seq)));
3416 t = gimple_assign_lhs (gimple_seq_last (seq));
3417 gimple_seq_set_location (seq, loc);
3418 gsi_insert_seq_after (&gsi, seq, GSI_CONTINUE_LINKING);
ff326078 3419
3420 /* For non-constant, misaligned or otherwise weird access sizes,
f9acf11a 3421 check first and last byte. */
3422 if (size_in_bytes == -1)
ff326078 3423 {
e9cf809e 3424 g = gimple_build_assign (make_ssa_name (pointer_sized_int_node),
3425 MINUS_EXPR, len,
3426 build_int_cst (pointer_sized_int_node, 1));
ff326078 3427 gimple_set_location (g, loc);
3428 gsi_insert_after (&gsi, g, GSI_NEW_STMT);
3429 tree last = gimple_assign_lhs (g);
e9cf809e 3430 g = gimple_build_assign (make_ssa_name (pointer_sized_int_node),
3431 PLUS_EXPR, base_addr, last);
ff326078 3432 gimple_set_location (g, loc);
3433 gsi_insert_after (&gsi, g, GSI_NEW_STMT);
3434 tree base_end_addr = gimple_assign_lhs (g);
3435
3436 tree shadow = build_shadow_mem_access (&gsi, loc, base_end_addr,
3437 shadow_ptr_type);
42acab1c 3438 gimple *shadow_test = build_assign (NE_EXPR, shadow, 0);
ff326078 3439 gimple_seq seq = NULL;
3440 gimple_seq_add_stmt (&seq, shadow_test);
3441 gimple_seq_add_stmt (&seq, build_assign (BIT_AND_EXPR,
3442 base_end_addr, 7));
3443 gimple_seq_add_stmt (&seq, build_type_cast (shadow_type,
3444 gimple_seq_last (seq)));
3445 gimple_seq_add_stmt (&seq, build_assign (GE_EXPR,
3446 gimple_seq_last (seq),
3447 shadow));
3448 gimple_seq_add_stmt (&seq, build_assign (BIT_AND_EXPR, shadow_test,
3449 gimple_seq_last (seq)));
f9acf11a 3450 gimple_seq_add_stmt (&seq, build_assign (BIT_IOR_EXPR, t,
3451 gimple_seq_last (seq)));
ff326078 3452 t = gimple_assign_lhs (gimple_seq_last (seq));
3453 gimple_seq_set_location (seq, loc);
3454 gsi_insert_seq_after (&gsi, seq, GSI_CONTINUE_LINKING);
3455 }
3456 }
3457
3458 g = gimple_build_cond (NE_EXPR, t, build_int_cst (TREE_TYPE (t), 0),
3459 NULL_TREE, NULL_TREE);
3460 gimple_set_location (g, loc);
3461 gsi_insert_after (&gsi, g, GSI_NEW_STMT);
3462
3463 /* Generate call to the run-time library (e.g. __asan_report_load8). */
3464 gsi = gsi_start_bb (then_bb);
3465 int nargs;
f4d482a6 3466 tree fun = report_error_func (is_store, recover_p, size_in_bytes, &nargs);
ff326078 3467 g = gimple_build_call (fun, nargs, base_addr, len);
3468 gimple_set_location (g, loc);
3469 gsi_insert_after (&gsi, g, GSI_NEW_STMT);
3470
3471 gsi_remove (iter, true);
3472 *iter = gsi_start_bb (else_bb);
3473
3474 return true;
3475}
3476
c51887c5 3477/* Create ASAN shadow variable for a VAR_DECL which has been rewritten
3478 into SSA. Already seen VAR_DECLs are stored in SHADOW_VARS_MAPPING. */
3479
3480static tree
3481create_asan_shadow_var (tree var_decl,
3482 hash_map<tree, tree> &shadow_vars_mapping)
3483{
3484 tree *slot = shadow_vars_mapping.get (var_decl);
3485 if (slot == NULL)
3486 {
3487 tree shadow_var = copy_node (var_decl);
3488
3489 copy_body_data id;
3490 memset (&id, 0, sizeof (copy_body_data));
3491 id.src_fn = id.dst_fn = current_function_decl;
3492 copy_decl_for_dup_finish (&id, var_decl, shadow_var);
3493
3494 DECL_ARTIFICIAL (shadow_var) = 1;
3495 DECL_IGNORED_P (shadow_var) = 1;
3496 DECL_SEEN_IN_BIND_EXPR_P (shadow_var) = 0;
3497 gimple_add_tmp_var (shadow_var);
3498
3499 shadow_vars_mapping.put (var_decl, shadow_var);
3500 return shadow_var;
3501 }
3502 else
3503 return *slot;
3504}
3505
ba39c1d4 3506/* Expand ASAN_POISON ifn. */
3507
c51887c5 3508bool
3509asan_expand_poison_ifn (gimple_stmt_iterator *iter,
3510 bool *need_commit_edge_insert,
3511 hash_map<tree, tree> &shadow_vars_mapping)
3512{
3513 gimple *g = gsi_stmt (*iter);
3514 tree poisoned_var = gimple_call_lhs (g);
947c0c36 3515 if (!poisoned_var || has_zero_uses (poisoned_var))
c51887c5 3516 {
3517 gsi_remove (iter, true);
3518 return true;
3519 }
3520
947c0c36 3521 if (SSA_NAME_VAR (poisoned_var) == NULL_TREE)
3522 SET_SSA_NAME_VAR_OR_IDENTIFIER (poisoned_var,
3523 create_tmp_var (TREE_TYPE (poisoned_var)));
3524
ba39c1d4 3525 tree shadow_var = create_asan_shadow_var (SSA_NAME_VAR (poisoned_var),
3526 shadow_vars_mapping);
c51887c5 3527
3528 bool recover_p;
3529 if (flag_sanitize & SANITIZE_USER_ADDRESS)
3530 recover_p = (flag_sanitize_recover & SANITIZE_USER_ADDRESS) != 0;
3531 else
3532 recover_p = (flag_sanitize_recover & SANITIZE_KERNEL_ADDRESS) != 0;
3533 tree size = DECL_SIZE_UNIT (shadow_var);
3534 gimple *poison_call
3535 = gimple_build_call_internal (IFN_ASAN_MARK, 3,
3536 build_int_cst (integer_type_node,
3537 ASAN_MARK_POISON),
3538 build_fold_addr_expr (shadow_var), size);
3539
ba39c1d4 3540 gimple *use;
c51887c5 3541 imm_use_iterator imm_iter;
ba39c1d4 3542 FOR_EACH_IMM_USE_STMT (use, imm_iter, poisoned_var)
c51887c5 3543 {
c51887c5 3544 if (is_gimple_debug (use))
3545 continue;
3546
3547 int nargs;
ba39c1d4 3548 bool store_p = gimple_call_internal_p (use, IFN_ASAN_POISON_USE);
3549 tree fun = report_error_func (store_p, recover_p, tree_to_uhwi (size),
c51887c5 3550 &nargs);
3551
3552 gcall *call = gimple_build_call (fun, 1,
3553 build_fold_addr_expr (shadow_var));
3554 gimple_set_location (call, gimple_location (use));
3555 gimple *call_to_insert = call;
3556
3557 /* The USE can be a gimple PHI node. If so, insert the call on
3558 all edges leading to the PHI node. */
3559 if (is_a <gphi *> (use))
3560 {
3561 gphi *phi = dyn_cast<gphi *> (use);
3562 for (unsigned i = 0; i < gimple_phi_num_args (phi); ++i)
3563 if (gimple_phi_arg_def (phi, i) == poisoned_var)
3564 {
3565 edge e = gimple_phi_arg_edge (phi, i);
3566
dad472c2 3567 /* Do not insert on an edge we can't split. */
3568 if (e->flags & EDGE_ABNORMAL)
3569 continue;
3570
c51887c5 3571 if (call_to_insert == NULL)
3572 call_to_insert = gimple_copy (call);
3573
3574 gsi_insert_seq_on_edge (e, call_to_insert);
3575 *need_commit_edge_insert = true;
3576 call_to_insert = NULL;
3577 }
3578 }
3579 else
3580 {
3581 gimple_stmt_iterator gsi = gsi_for_stmt (use);
ba39c1d4 3582 if (store_p)
3583 gsi_replace (&gsi, call, true);
3584 else
3585 gsi_insert_before (&gsi, call, GSI_NEW_STMT);
c51887c5 3586 }
3587 }
3588
3589 SSA_NAME_IS_DEFAULT_DEF (poisoned_var) = true;
3590 SSA_NAME_DEF_STMT (poisoned_var) = gimple_build_nop ();
3591 gsi_replace (iter, poison_call, false);
3592
3593 return true;
3594}
3595
b92cccf4 3596/* Instrument the current function. */
3597
3598static unsigned int
3599asan_instrument (void)
3600{
5d5c682b 3601 if (shadow_ptr_types[0] == NULL_TREE)
55b58027 3602 asan_init_shadow_ptr_types ();
b92cccf4 3603 transform_statements ();
d08919a7 3604 last_alloca_addr = NULL_TREE;
b92cccf4 3605 return 0;
3606}
3607
3608static bool
3609gate_asan (void)
3610{
9917317a 3611 return sanitize_flags_p (SANITIZE_ADDRESS);
b92cccf4 3612}
3613
cbe8bda8 3614namespace {
3615
3616const pass_data pass_data_asan =
b92cccf4 3617{
cbe8bda8 3618 GIMPLE_PASS, /* type */
3619 "asan", /* name */
3620 OPTGROUP_NONE, /* optinfo_flags */
cbe8bda8 3621 TV_NONE, /* tv_id */
3622 ( PROP_ssa | PROP_cfg | PROP_gimple_leh ), /* properties_required */
3623 0, /* properties_provided */
3624 0, /* properties_destroyed */
3625 0, /* todo_flags_start */
8b88439e 3626 TODO_update_ssa, /* todo_flags_finish */
b92cccf4 3627};
5d5c682b 3628
cbe8bda8 3629class pass_asan : public gimple_opt_pass
3630{
3631public:
9af5ce0c 3632 pass_asan (gcc::context *ctxt)
3633 : gimple_opt_pass (pass_data_asan, ctxt)
cbe8bda8 3634 {}
3635
3636 /* opt_pass methods: */
ae84f584 3637 opt_pass * clone () { return new pass_asan (m_ctxt); }
31315c24 3638 virtual bool gate (function *) { return gate_asan (); }
65b0537f 3639 virtual unsigned int execute (function *) { return asan_instrument (); }
cbe8bda8 3640
3641}; // class pass_asan
3642
3643} // anon namespace
3644
3645gimple_opt_pass *
3646make_pass_asan (gcc::context *ctxt)
3647{
3648 return new pass_asan (ctxt);
3649}
3650
cbe8bda8 3651namespace {
3652
3653const pass_data pass_data_asan_O0 =
8293ee35 3654{
cbe8bda8 3655 GIMPLE_PASS, /* type */
3656 "asan0", /* name */
3657 OPTGROUP_NONE, /* optinfo_flags */
cbe8bda8 3658 TV_NONE, /* tv_id */
3659 ( PROP_ssa | PROP_cfg | PROP_gimple_leh ), /* properties_required */
3660 0, /* properties_provided */
3661 0, /* properties_destroyed */
3662 0, /* todo_flags_start */
8b88439e 3663 TODO_update_ssa, /* todo_flags_finish */
8293ee35 3664};
3665
cbe8bda8 3666class pass_asan_O0 : public gimple_opt_pass
3667{
3668public:
9af5ce0c 3669 pass_asan_O0 (gcc::context *ctxt)
3670 : gimple_opt_pass (pass_data_asan_O0, ctxt)
cbe8bda8 3671 {}
3672
3673 /* opt_pass methods: */
31315c24 3674 virtual bool gate (function *) { return !optimize && gate_asan (); }
65b0537f 3675 virtual unsigned int execute (function *) { return asan_instrument (); }
cbe8bda8 3676
3677}; // class pass_asan_O0
3678
3679} // anon namespace
3680
3681gimple_opt_pass *
3682make_pass_asan_O0 (gcc::context *ctxt)
3683{
3684 return new pass_asan_O0 (ctxt);
3685}
3686
5d5c682b 3687#include "gt-asan.h"