Don't warn when alignment of global common data exceeds maximum alignment.
[official-gcc.git] / gcc / ubsan.c
blobba9adf0ad96cac4aa80571d529ce59455a827f2c
1 /* UndefinedBehaviorSanitizer, undefined behavior detector.
2 Copyright (C) 2013-2021 Free Software Foundation, Inc.
3 Contributed by Marek Polacek <polacek@redhat.com>
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 3, or (at your option) any later
10 version.
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 for more details.
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING3. If not see
19 <http://www.gnu.org/licenses/>. */
21 #include "config.h"
22 #include "system.h"
23 #include "coretypes.h"
24 #include "backend.h"
25 #include "rtl.h"
26 #include "c-family/c-common.h"
27 #include "gimple.h"
28 #include "cfghooks.h"
29 #include "tree-pass.h"
30 #include "memmodel.h"
31 #include "tm_p.h"
32 #include "ssa.h"
33 #include "cgraph.h"
34 #include "tree-pretty-print.h"
35 #include "stor-layout.h"
36 #include "cfganal.h"
37 #include "gimple-iterator.h"
38 #include "output.h"
39 #include "cfgloop.h"
40 #include "ubsan.h"
41 #include "expr.h"
42 #include "stringpool.h"
43 #include "attribs.h"
44 #include "asan.h"
45 #include "gimplify-me.h"
46 #include "dfp.h"
47 #include "builtins.h"
48 #include "tree-object-size.h"
49 #include "tree-cfg.h"
50 #include "gimple-fold.h"
51 #include "varasm.h"
53 /* Map from a tree to a VAR_DECL tree. */
55 struct GTY((for_user)) tree_type_map {
56 struct tree_map_base type;
57 tree decl;
60 struct tree_type_map_cache_hasher : ggc_cache_ptr_hash<tree_type_map>
62 static inline hashval_t
63 hash (tree_type_map *t)
65 return TYPE_UID (t->type.from);
68 static inline bool
69 equal (tree_type_map *a, tree_type_map *b)
71 return a->type.from == b->type.from;
74 static int
75 keep_cache_entry (tree_type_map *&m)
77 return ggc_marked_p (m->type.from);
81 static GTY ((cache))
82 hash_table<tree_type_map_cache_hasher> *decl_tree_for_type;
84 /* Lookup a VAR_DECL for TYPE, and return it if we find one. */
86 static tree
87 decl_for_type_lookup (tree type)
89 /* If the hash table is not initialized yet, create it now. */
90 if (decl_tree_for_type == NULL)
92 decl_tree_for_type
93 = hash_table<tree_type_map_cache_hasher>::create_ggc (10);
94 /* That also means we don't have to bother with the lookup. */
95 return NULL_TREE;
98 struct tree_type_map *h, in;
99 in.type.from = type;
101 h = decl_tree_for_type->find_with_hash (&in, TYPE_UID (type));
102 return h ? h->decl : NULL_TREE;
105 /* Insert a mapping TYPE->DECL in the VAR_DECL for type hashtable. */
107 static void
108 decl_for_type_insert (tree type, tree decl)
110 struct tree_type_map *h;
112 h = ggc_alloc<tree_type_map> ();
113 h->type.from = type;
114 h->decl = decl;
115 *decl_tree_for_type->find_slot_with_hash (h, TYPE_UID (type), INSERT) = h;
118 /* Helper routine, which encodes a value in the pointer_sized_int_node.
119 Arguments with precision <= POINTER_SIZE are passed directly,
120 the rest is passed by reference. T is a value we are to encode.
121 PHASE determines when this function is called. */
123 tree
124 ubsan_encode_value (tree t, enum ubsan_encode_value_phase phase)
126 tree type = TREE_TYPE (t);
127 scalar_mode mode = SCALAR_TYPE_MODE (type);
128 const unsigned int bitsize = GET_MODE_BITSIZE (mode);
129 if (bitsize <= POINTER_SIZE)
130 switch (TREE_CODE (type))
132 case BOOLEAN_TYPE:
133 case ENUMERAL_TYPE:
134 case INTEGER_TYPE:
135 return fold_build1 (NOP_EXPR, pointer_sized_int_node, t);
136 case REAL_TYPE:
138 tree itype = build_nonstandard_integer_type (bitsize, true);
139 t = fold_build1 (VIEW_CONVERT_EXPR, itype, t);
140 return fold_convert (pointer_sized_int_node, t);
142 default:
143 gcc_unreachable ();
145 else
147 if (!DECL_P (t) || !TREE_ADDRESSABLE (t))
149 /* The reason for this is that we don't want to pessimize
150 code by making vars unnecessarily addressable. */
151 tree var;
152 if (phase != UBSAN_ENCODE_VALUE_GENERIC)
154 var = create_tmp_var (type);
155 mark_addressable (var);
157 else
159 var = create_tmp_var_raw (type);
160 TREE_ADDRESSABLE (var) = 1;
161 DECL_CONTEXT (var) = current_function_decl;
163 if (phase == UBSAN_ENCODE_VALUE_RTL)
165 rtx mem = assign_stack_temp_for_type (mode, GET_MODE_SIZE (mode),
166 type);
167 SET_DECL_RTL (var, mem);
168 expand_assignment (var, t, false);
169 return build_fold_addr_expr (var);
171 if (phase != UBSAN_ENCODE_VALUE_GENERIC)
173 tree tem = build2 (MODIFY_EXPR, void_type_node, var, t);
174 t = build_fold_addr_expr (var);
175 return build2 (COMPOUND_EXPR, TREE_TYPE (t), tem, t);
177 else
179 var = build4 (TARGET_EXPR, type, var, t, NULL_TREE, NULL_TREE);
180 return build_fold_addr_expr (var);
183 else
184 return build_fold_addr_expr (t);
188 /* Cached ubsan_get_type_descriptor_type () return value. */
189 static GTY(()) tree ubsan_type_descriptor_type;
191 /* Build
192 struct __ubsan_type_descriptor
194 unsigned short __typekind;
195 unsigned short __typeinfo;
196 char __typename[];
198 type. */
200 static tree
201 ubsan_get_type_descriptor_type (void)
203 static const char *field_names[3]
204 = { "__typekind", "__typeinfo", "__typename" };
205 tree fields[3], ret;
207 if (ubsan_type_descriptor_type)
208 return ubsan_type_descriptor_type;
210 tree itype = build_range_type (sizetype, size_zero_node, NULL_TREE);
211 tree flex_arr_type = build_array_type (char_type_node, itype);
213 ret = make_node (RECORD_TYPE);
214 for (int i = 0; i < 3; i++)
216 fields[i] = build_decl (UNKNOWN_LOCATION, FIELD_DECL,
217 get_identifier (field_names[i]),
218 (i == 2) ? flex_arr_type
219 : short_unsigned_type_node);
220 DECL_CONTEXT (fields[i]) = ret;
221 if (i)
222 DECL_CHAIN (fields[i - 1]) = fields[i];
224 tree type_decl = build_decl (input_location, TYPE_DECL,
225 get_identifier ("__ubsan_type_descriptor"),
226 ret);
227 DECL_IGNORED_P (type_decl) = 1;
228 DECL_ARTIFICIAL (type_decl) = 1;
229 TYPE_FIELDS (ret) = fields[0];
230 TYPE_NAME (ret) = type_decl;
231 TYPE_STUB_DECL (ret) = type_decl;
232 TYPE_ARTIFICIAL (ret) = 1;
233 layout_type (ret);
234 ubsan_type_descriptor_type = ret;
235 return ret;
238 /* Cached ubsan_get_source_location_type () return value. */
239 static GTY(()) tree ubsan_source_location_type;
241 /* Build
242 struct __ubsan_source_location
244 const char *__filename;
245 unsigned int __line;
246 unsigned int __column;
248 type. */
250 tree
251 ubsan_get_source_location_type (void)
253 static const char *field_names[3]
254 = { "__filename", "__line", "__column" };
255 tree fields[3], ret;
256 if (ubsan_source_location_type)
257 return ubsan_source_location_type;
259 tree const_char_type = build_qualified_type (char_type_node,
260 TYPE_QUAL_CONST);
262 ret = make_node (RECORD_TYPE);
263 for (int i = 0; i < 3; i++)
265 fields[i] = build_decl (UNKNOWN_LOCATION, FIELD_DECL,
266 get_identifier (field_names[i]),
267 (i == 0) ? build_pointer_type (const_char_type)
268 : unsigned_type_node);
269 DECL_CONTEXT (fields[i]) = ret;
270 if (i)
271 DECL_CHAIN (fields[i - 1]) = fields[i];
273 tree type_decl = build_decl (input_location, TYPE_DECL,
274 get_identifier ("__ubsan_source_location"),
275 ret);
276 DECL_IGNORED_P (type_decl) = 1;
277 DECL_ARTIFICIAL (type_decl) = 1;
278 TYPE_FIELDS (ret) = fields[0];
279 TYPE_NAME (ret) = type_decl;
280 TYPE_STUB_DECL (ret) = type_decl;
281 TYPE_ARTIFICIAL (ret) = 1;
282 layout_type (ret);
283 ubsan_source_location_type = ret;
284 return ret;
287 /* Helper routine that returns a CONSTRUCTOR of __ubsan_source_location
288 type with its fields filled from a location_t LOC. */
290 static tree
291 ubsan_source_location (location_t loc)
293 expanded_location xloc;
294 tree type = ubsan_get_source_location_type ();
296 xloc = expand_location (loc);
297 tree str;
298 if (xloc.file == NULL)
300 str = build_int_cst (ptr_type_node, 0);
301 xloc.line = 0;
302 xloc.column = 0;
304 else
306 /* Fill in the values from LOC. */
307 size_t len = strlen (xloc.file) + 1;
308 str = build_string (len, xloc.file);
309 TREE_TYPE (str) = build_array_type_nelts (char_type_node, len);
310 TREE_READONLY (str) = 1;
311 TREE_STATIC (str) = 1;
312 str = build_fold_addr_expr (str);
314 tree ctor = build_constructor_va (type, 3, NULL_TREE, str, NULL_TREE,
315 build_int_cst (unsigned_type_node,
316 xloc.line), NULL_TREE,
317 build_int_cst (unsigned_type_node,
318 xloc.column));
319 TREE_CONSTANT (ctor) = 1;
320 TREE_STATIC (ctor) = 1;
322 return ctor;
325 /* This routine returns a magic number for TYPE. */
327 static unsigned short
328 get_ubsan_type_info_for_type (tree type)
330 if (TREE_CODE (type) == REAL_TYPE)
331 return tree_to_uhwi (TYPE_SIZE (type));
332 else if (INTEGRAL_TYPE_P (type))
334 int prec = exact_log2 (tree_to_uhwi (TYPE_SIZE (type)));
335 gcc_assert (prec != -1);
336 return (prec << 1) | !TYPE_UNSIGNED (type);
338 else
339 return 0;
342 /* Counters for internal labels. ubsan_ids[0] for Lubsan_type,
343 ubsan_ids[1] for Lubsan_data labels. */
344 static GTY(()) unsigned int ubsan_ids[2];
346 /* Helper routine that returns ADDR_EXPR of a VAR_DECL of a type
347 descriptor. It first looks into the hash table; if not found,
348 create the VAR_DECL, put it into the hash table and return the
349 ADDR_EXPR of it. TYPE describes a particular type. PSTYLE is
350 an enum controlling how we want to print the type. */
352 tree
353 ubsan_type_descriptor (tree type, enum ubsan_print_style pstyle)
355 /* See through any typedefs. */
356 type = TYPE_MAIN_VARIANT (type);
358 tree decl = decl_for_type_lookup (type);
359 /* It is possible that some of the earlier created DECLs were found
360 unused, in that case they weren't emitted and varpool_node::get
361 returns NULL node on them. But now we really need them. Thus,
362 renew them here. */
363 if (decl != NULL_TREE && varpool_node::get (decl))
364 return build_fold_addr_expr (decl);
366 tree dtype = ubsan_get_type_descriptor_type ();
367 tree type2 = type;
368 const char *tname = NULL;
369 pretty_printer pretty_name;
370 unsigned char deref_depth = 0;
371 unsigned short tkind, tinfo;
373 /* Get the name of the type, or the name of the pointer type. */
374 if (pstyle == UBSAN_PRINT_POINTER)
376 gcc_assert (POINTER_TYPE_P (type));
377 type2 = TREE_TYPE (type);
379 /* Remove any '*' operators from TYPE. */
380 while (POINTER_TYPE_P (type2))
381 deref_depth++, type2 = TREE_TYPE (type2);
383 if (TREE_CODE (type2) == METHOD_TYPE)
384 type2 = TYPE_METHOD_BASETYPE (type2);
387 /* If an array, get its type. */
388 type2 = strip_array_types (type2);
390 if (pstyle == UBSAN_PRINT_ARRAY)
392 while (POINTER_TYPE_P (type2))
393 deref_depth++, type2 = TREE_TYPE (type2);
396 if (TYPE_NAME (type2) != NULL)
398 if (TREE_CODE (TYPE_NAME (type2)) == IDENTIFIER_NODE)
399 tname = IDENTIFIER_POINTER (TYPE_NAME (type2));
400 else if (DECL_NAME (TYPE_NAME (type2)) != NULL)
401 tname = IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (type2)));
404 if (tname == NULL)
405 /* We weren't able to determine the type name. */
406 tname = "<unknown>";
408 pp_quote (&pretty_name);
410 tree eltype = type;
411 if (pstyle == UBSAN_PRINT_POINTER)
413 pp_printf (&pretty_name, "%s%s%s%s%s%s%s",
414 TYPE_VOLATILE (type2) ? "volatile " : "",
415 TYPE_READONLY (type2) ? "const " : "",
416 TYPE_RESTRICT (type2) ? "restrict " : "",
417 TYPE_ATOMIC (type2) ? "_Atomic " : "",
418 TREE_CODE (type2) == RECORD_TYPE
419 ? "struct "
420 : TREE_CODE (type2) == UNION_TYPE
421 ? "union " : "", tname,
422 deref_depth == 0 ? "" : " ");
423 while (deref_depth-- > 0)
424 pp_star (&pretty_name);
426 else if (pstyle == UBSAN_PRINT_ARRAY)
428 /* Pretty print the array dimensions. */
429 gcc_assert (TREE_CODE (type) == ARRAY_TYPE);
430 tree t = type;
431 pp_string (&pretty_name, tname);
432 pp_space (&pretty_name);
433 while (deref_depth-- > 0)
434 pp_star (&pretty_name);
435 while (TREE_CODE (t) == ARRAY_TYPE)
437 pp_left_bracket (&pretty_name);
438 tree dom = TYPE_DOMAIN (t);
439 if (dom != NULL_TREE
440 && TYPE_MAX_VALUE (dom) != NULL_TREE
441 && TREE_CODE (TYPE_MAX_VALUE (dom)) == INTEGER_CST)
443 unsigned HOST_WIDE_INT m;
444 if (tree_fits_uhwi_p (TYPE_MAX_VALUE (dom))
445 && (m = tree_to_uhwi (TYPE_MAX_VALUE (dom))) + 1 != 0)
446 pp_unsigned_wide_integer (&pretty_name, m + 1);
447 else
448 pp_wide_int (&pretty_name,
449 wi::add (wi::to_widest (TYPE_MAX_VALUE (dom)), 1),
450 TYPE_SIGN (TREE_TYPE (dom)));
452 else
453 /* ??? We can't determine the variable name; print VLA unspec. */
454 pp_star (&pretty_name);
455 pp_right_bracket (&pretty_name);
456 t = TREE_TYPE (t);
459 /* Save the tree with stripped types. */
460 eltype = t;
462 else
463 pp_string (&pretty_name, tname);
465 pp_quote (&pretty_name);
467 switch (TREE_CODE (eltype))
469 case BOOLEAN_TYPE:
470 case ENUMERAL_TYPE:
471 case INTEGER_TYPE:
472 tkind = 0x0000;
473 break;
474 case REAL_TYPE:
475 /* FIXME: libubsan right now only supports float, double and
476 long double type formats. */
477 if (TYPE_MODE (eltype) == TYPE_MODE (float_type_node)
478 || TYPE_MODE (eltype) == TYPE_MODE (double_type_node)
479 || TYPE_MODE (eltype) == TYPE_MODE (long_double_type_node))
480 tkind = 0x0001;
481 else
482 tkind = 0xffff;
483 break;
484 default:
485 tkind = 0xffff;
486 break;
488 tinfo = get_ubsan_type_info_for_type (eltype);
490 /* Create a new VAR_DECL of type descriptor. */
491 const char *tmp = pp_formatted_text (&pretty_name);
492 size_t len = strlen (tmp) + 1;
493 tree str = build_string (len, tmp);
494 TREE_TYPE (str) = build_array_type_nelts (char_type_node, len);
495 TREE_READONLY (str) = 1;
496 TREE_STATIC (str) = 1;
498 char tmp_name[32];
499 ASM_GENERATE_INTERNAL_LABEL (tmp_name, "Lubsan_type", ubsan_ids[0]++);
500 decl = build_decl (UNKNOWN_LOCATION, VAR_DECL, get_identifier (tmp_name),
501 dtype);
502 TREE_STATIC (decl) = 1;
503 TREE_PUBLIC (decl) = 0;
504 DECL_ARTIFICIAL (decl) = 1;
505 DECL_IGNORED_P (decl) = 1;
506 DECL_EXTERNAL (decl) = 0;
507 DECL_SIZE (decl)
508 = size_binop (PLUS_EXPR, DECL_SIZE (decl), TYPE_SIZE (TREE_TYPE (str)));
509 DECL_SIZE_UNIT (decl)
510 = size_binop (PLUS_EXPR, DECL_SIZE_UNIT (decl),
511 TYPE_SIZE_UNIT (TREE_TYPE (str)));
513 tree ctor = build_constructor_va (dtype, 3, NULL_TREE,
514 build_int_cst (short_unsigned_type_node,
515 tkind), NULL_TREE,
516 build_int_cst (short_unsigned_type_node,
517 tinfo), NULL_TREE, str);
518 TREE_CONSTANT (ctor) = 1;
519 TREE_STATIC (ctor) = 1;
520 DECL_INITIAL (decl) = ctor;
521 varpool_node::finalize_decl (decl);
523 /* Save the VAR_DECL into the hash table. */
524 decl_for_type_insert (type, decl);
526 return build_fold_addr_expr (decl);
529 /* Create a structure for the ubsan library. NAME is a name of the new
530 structure. LOCCNT is number of locations, PLOC points to array of
531 locations. The arguments in ... are of __ubsan_type_descriptor type
532 and there are at most two of them, followed by NULL_TREE, followed
533 by optional extra arguments and another NULL_TREE. */
535 tree
536 ubsan_create_data (const char *name, int loccnt, const location_t *ploc, ...)
538 va_list args;
539 tree ret, t;
540 tree fields[6];
541 vec<tree, va_gc> *saved_args = NULL;
542 size_t i = 0;
543 int j;
545 /* It is possible that PCH zapped table with definitions of sanitizer
546 builtins. Reinitialize them if needed. */
547 initialize_sanitizer_builtins ();
549 /* Firstly, create a pointer to type descriptor type. */
550 tree td_type = ubsan_get_type_descriptor_type ();
551 td_type = build_pointer_type (td_type);
553 /* Create the structure type. */
554 ret = make_node (RECORD_TYPE);
555 for (j = 0; j < loccnt; j++)
557 gcc_checking_assert (i < 2);
558 fields[i] = build_decl (UNKNOWN_LOCATION, FIELD_DECL, NULL_TREE,
559 ubsan_get_source_location_type ());
560 DECL_CONTEXT (fields[i]) = ret;
561 if (i)
562 DECL_CHAIN (fields[i - 1]) = fields[i];
563 i++;
566 va_start (args, ploc);
567 for (t = va_arg (args, tree); t != NULL_TREE;
568 i++, t = va_arg (args, tree))
570 gcc_checking_assert (i < 4);
571 /* Save the tree arguments for later use. */
572 vec_safe_push (saved_args, t);
573 fields[i] = build_decl (UNKNOWN_LOCATION, FIELD_DECL, NULL_TREE,
574 td_type);
575 DECL_CONTEXT (fields[i]) = ret;
576 if (i)
577 DECL_CHAIN (fields[i - 1]) = fields[i];
580 for (t = va_arg (args, tree); t != NULL_TREE;
581 i++, t = va_arg (args, tree))
583 gcc_checking_assert (i < 6);
584 /* Save the tree arguments for later use. */
585 vec_safe_push (saved_args, t);
586 fields[i] = build_decl (UNKNOWN_LOCATION, FIELD_DECL, NULL_TREE,
587 TREE_TYPE (t));
588 DECL_CONTEXT (fields[i]) = ret;
589 if (i)
590 DECL_CHAIN (fields[i - 1]) = fields[i];
592 va_end (args);
594 tree type_decl = build_decl (input_location, TYPE_DECL,
595 get_identifier (name), ret);
596 DECL_IGNORED_P (type_decl) = 1;
597 DECL_ARTIFICIAL (type_decl) = 1;
598 TYPE_FIELDS (ret) = fields[0];
599 TYPE_NAME (ret) = type_decl;
600 TYPE_STUB_DECL (ret) = type_decl;
601 TYPE_ARTIFICIAL (ret) = 1;
602 layout_type (ret);
604 /* Now, fill in the type. */
605 char tmp_name[32];
606 ASM_GENERATE_INTERNAL_LABEL (tmp_name, "Lubsan_data", ubsan_ids[1]++);
607 tree var = build_decl (UNKNOWN_LOCATION, VAR_DECL, get_identifier (tmp_name),
608 ret);
609 TREE_STATIC (var) = 1;
610 TREE_PUBLIC (var) = 0;
611 DECL_ARTIFICIAL (var) = 1;
612 DECL_IGNORED_P (var) = 1;
613 DECL_EXTERNAL (var) = 0;
615 vec<constructor_elt, va_gc> *v;
616 vec_alloc (v, i);
617 tree ctor = build_constructor (ret, v);
619 /* If desirable, set the __ubsan_source_location element. */
620 for (j = 0; j < loccnt; j++)
622 location_t loc = LOCATION_LOCUS (ploc[j]);
623 CONSTRUCTOR_APPEND_ELT (v, NULL_TREE, ubsan_source_location (loc));
626 size_t nelts = vec_safe_length (saved_args);
627 for (i = 0; i < nelts; i++)
629 t = (*saved_args)[i];
630 CONSTRUCTOR_APPEND_ELT (v, NULL_TREE, t);
633 TREE_CONSTANT (ctor) = 1;
634 TREE_STATIC (ctor) = 1;
635 DECL_INITIAL (var) = ctor;
636 varpool_node::finalize_decl (var);
638 return var;
641 /* Instrument the __builtin_unreachable call. We just call the libubsan
642 routine instead. */
644 bool
645 ubsan_instrument_unreachable (gimple_stmt_iterator *gsi)
647 gimple *g;
648 location_t loc = gimple_location (gsi_stmt (*gsi));
650 if (flag_sanitize_undefined_trap_on_error)
651 g = gimple_build_call (builtin_decl_explicit (BUILT_IN_TRAP), 0);
652 else
654 tree data = ubsan_create_data ("__ubsan_unreachable_data", 1, &loc,
655 NULL_TREE, NULL_TREE);
656 data = build_fold_addr_expr_loc (loc, data);
657 tree fn
658 = builtin_decl_explicit (BUILT_IN_UBSAN_HANDLE_BUILTIN_UNREACHABLE);
659 g = gimple_build_call (fn, 1, data);
661 gimple_set_location (g, loc);
662 gsi_replace (gsi, g, false);
663 return false;
666 /* Return true if T is a call to a libubsan routine. */
668 bool
669 is_ubsan_builtin_p (tree t)
671 return TREE_CODE (t) == FUNCTION_DECL
672 && fndecl_built_in_p (t, BUILT_IN_NORMAL)
673 && strncmp (IDENTIFIER_POINTER (DECL_NAME (t)),
674 "__builtin___ubsan_", 18) == 0;
677 /* Create a callgraph edge for statement STMT. */
679 static void
680 ubsan_create_edge (gimple *stmt)
682 gcall *call_stmt = dyn_cast <gcall *> (stmt);
683 basic_block bb = gimple_bb (stmt);
684 cgraph_node *node = cgraph_node::get (current_function_decl);
685 tree decl = gimple_call_fndecl (call_stmt);
686 if (decl)
687 node->create_edge (cgraph_node::get_create (decl), call_stmt, bb->count);
690 /* Expand the UBSAN_BOUNDS special builtin function. */
692 bool
693 ubsan_expand_bounds_ifn (gimple_stmt_iterator *gsi)
695 gimple *stmt = gsi_stmt (*gsi);
696 location_t loc = gimple_location (stmt);
697 gcc_assert (gimple_call_num_args (stmt) == 3);
699 /* Pick up the arguments of the UBSAN_BOUNDS call. */
700 tree type = TREE_TYPE (TREE_TYPE (gimple_call_arg (stmt, 0)));
701 tree index = gimple_call_arg (stmt, 1);
702 tree orig_index = index;
703 tree bound = gimple_call_arg (stmt, 2);
705 gimple_stmt_iterator gsi_orig = *gsi;
707 /* Create condition "if (index > bound)". */
708 basic_block then_bb, fallthru_bb;
709 gimple_stmt_iterator cond_insert_point
710 = create_cond_insert_point (gsi, false, false, true,
711 &then_bb, &fallthru_bb);
712 index = fold_convert (TREE_TYPE (bound), index);
713 index = force_gimple_operand_gsi (&cond_insert_point, index,
714 true, NULL_TREE,
715 false, GSI_NEW_STMT);
716 gimple *g = gimple_build_cond (GT_EXPR, index, bound, NULL_TREE, NULL_TREE);
717 gimple_set_location (g, loc);
718 gsi_insert_after (&cond_insert_point, g, GSI_NEW_STMT);
720 /* Generate __ubsan_handle_out_of_bounds call. */
721 *gsi = gsi_after_labels (then_bb);
722 if (flag_sanitize_undefined_trap_on_error)
723 g = gimple_build_call (builtin_decl_explicit (BUILT_IN_TRAP), 0);
724 else
726 tree data
727 = ubsan_create_data ("__ubsan_out_of_bounds_data", 1, &loc,
728 ubsan_type_descriptor (type, UBSAN_PRINT_ARRAY),
729 ubsan_type_descriptor (TREE_TYPE (orig_index)),
730 NULL_TREE, NULL_TREE);
731 data = build_fold_addr_expr_loc (loc, data);
732 enum built_in_function bcode
733 = (flag_sanitize_recover & SANITIZE_BOUNDS)
734 ? BUILT_IN_UBSAN_HANDLE_OUT_OF_BOUNDS
735 : BUILT_IN_UBSAN_HANDLE_OUT_OF_BOUNDS_ABORT;
736 tree fn = builtin_decl_explicit (bcode);
737 tree val = ubsan_encode_value (orig_index, UBSAN_ENCODE_VALUE_GIMPLE);
738 val = force_gimple_operand_gsi (gsi, val, true, NULL_TREE, true,
739 GSI_SAME_STMT);
740 g = gimple_build_call (fn, 2, data, val);
742 gimple_set_location (g, loc);
743 gsi_insert_before (gsi, g, GSI_SAME_STMT);
745 /* Get rid of the UBSAN_BOUNDS call from the IR. */
746 unlink_stmt_vdef (stmt);
747 gsi_remove (&gsi_orig, true);
749 /* Point GSI to next logical statement. */
750 *gsi = gsi_start_bb (fallthru_bb);
751 return true;
754 /* Expand UBSAN_NULL internal call. The type is kept on the ckind
755 argument which is a constant, because the middle-end treats pointer
756 conversions as useless and therefore the type of the first argument
757 could be changed to any other pointer type. */
759 bool
760 ubsan_expand_null_ifn (gimple_stmt_iterator *gsip)
762 gimple_stmt_iterator gsi = *gsip;
763 gimple *stmt = gsi_stmt (gsi);
764 location_t loc = gimple_location (stmt);
765 gcc_assert (gimple_call_num_args (stmt) == 3);
766 tree ptr = gimple_call_arg (stmt, 0);
767 tree ckind = gimple_call_arg (stmt, 1);
768 tree align = gimple_call_arg (stmt, 2);
769 tree check_align = NULL_TREE;
770 bool check_null;
772 basic_block cur_bb = gsi_bb (gsi);
774 gimple *g;
775 if (!integer_zerop (align))
777 unsigned int ptralign = get_pointer_alignment (ptr) / BITS_PER_UNIT;
778 if (compare_tree_int (align, ptralign) == 1)
780 check_align = make_ssa_name (pointer_sized_int_node);
781 g = gimple_build_assign (check_align, NOP_EXPR, ptr);
782 gimple_set_location (g, loc);
783 gsi_insert_before (&gsi, g, GSI_SAME_STMT);
786 check_null = sanitize_flags_p (SANITIZE_NULL);
788 if (check_align == NULL_TREE && !check_null)
790 gsi_remove (gsip, true);
791 /* Unlink the UBSAN_NULLs vops before replacing it. */
792 unlink_stmt_vdef (stmt);
793 return true;
796 /* Split the original block holding the pointer dereference. */
797 edge e = split_block (cur_bb, stmt);
799 /* Get a hold on the 'condition block', the 'then block' and the
800 'else block'. */
801 basic_block cond_bb = e->src;
802 basic_block fallthru_bb = e->dest;
803 basic_block then_bb = create_empty_bb (cond_bb);
804 add_bb_to_loop (then_bb, cond_bb->loop_father);
805 loops_state_set (LOOPS_NEED_FIXUP);
807 /* Make an edge coming from the 'cond block' into the 'then block';
808 this edge is unlikely taken, so set up the probability accordingly. */
809 e = make_edge (cond_bb, then_bb, EDGE_TRUE_VALUE);
810 e->probability = profile_probability::very_unlikely ();
811 then_bb->count = e->count ();
813 /* Connect 'then block' with the 'else block'. This is needed
814 as the ubsan routines we call in the 'then block' are not noreturn.
815 The 'then block' only has one outcoming edge. */
816 make_single_succ_edge (then_bb, fallthru_bb, EDGE_FALLTHRU);
818 /* Set up the fallthrough basic block. */
819 e = find_edge (cond_bb, fallthru_bb);
820 e->flags = EDGE_FALSE_VALUE;
821 e->probability = profile_probability::very_likely ();
823 /* Update dominance info for the newly created then_bb; note that
824 fallthru_bb's dominance info has already been updated by
825 split_block. */
826 if (dom_info_available_p (CDI_DOMINATORS))
827 set_immediate_dominator (CDI_DOMINATORS, then_bb, cond_bb);
829 /* Put the ubsan builtin call into the newly created BB. */
830 if (flag_sanitize_undefined_trap_on_error)
831 g = gimple_build_call (builtin_decl_implicit (BUILT_IN_TRAP), 0);
832 else
834 enum built_in_function bcode
835 = (flag_sanitize_recover & ((check_align ? SANITIZE_ALIGNMENT : 0)
836 | (check_null ? SANITIZE_NULL : 0)))
837 ? BUILT_IN_UBSAN_HANDLE_TYPE_MISMATCH_V1
838 : BUILT_IN_UBSAN_HANDLE_TYPE_MISMATCH_V1_ABORT;
839 tree fn = builtin_decl_implicit (bcode);
840 int align_log = tree_log2 (align);
841 tree data
842 = ubsan_create_data ("__ubsan_null_data", 1, &loc,
843 ubsan_type_descriptor (TREE_TYPE (ckind),
844 UBSAN_PRINT_POINTER),
845 NULL_TREE,
846 build_int_cst (unsigned_char_type_node,
847 MAX (align_log, 0)),
848 fold_convert (unsigned_char_type_node, ckind),
849 NULL_TREE);
850 data = build_fold_addr_expr_loc (loc, data);
851 g = gimple_build_call (fn, 2, data,
852 check_align ? check_align
853 : build_zero_cst (pointer_sized_int_node));
855 gimple_stmt_iterator gsi2 = gsi_start_bb (then_bb);
856 gimple_set_location (g, loc);
857 gsi_insert_after (&gsi2, g, GSI_NEW_STMT);
859 /* Unlink the UBSAN_NULLs vops before replacing it. */
860 unlink_stmt_vdef (stmt);
862 if (check_null)
864 g = gimple_build_cond (EQ_EXPR, ptr, build_int_cst (TREE_TYPE (ptr), 0),
865 NULL_TREE, NULL_TREE);
866 gimple_set_location (g, loc);
868 /* Replace the UBSAN_NULL with a GIMPLE_COND stmt. */
869 gsi_replace (&gsi, g, false);
870 stmt = g;
873 if (check_align)
875 if (check_null)
877 /* Split the block with the condition again. */
878 e = split_block (cond_bb, stmt);
879 basic_block cond1_bb = e->src;
880 basic_block cond2_bb = e->dest;
882 /* Make an edge coming from the 'cond1 block' into the 'then block';
883 this edge is unlikely taken, so set up the probability
884 accordingly. */
885 e = make_edge (cond1_bb, then_bb, EDGE_TRUE_VALUE);
886 e->probability = profile_probability::very_unlikely ();
888 /* Set up the fallthrough basic block. */
889 e = find_edge (cond1_bb, cond2_bb);
890 e->flags = EDGE_FALSE_VALUE;
891 e->probability = profile_probability::very_likely ();
893 /* Update dominance info. */
894 if (dom_info_available_p (CDI_DOMINATORS))
896 set_immediate_dominator (CDI_DOMINATORS, fallthru_bb, cond1_bb);
897 set_immediate_dominator (CDI_DOMINATORS, then_bb, cond1_bb);
900 gsi2 = gsi_start_bb (cond2_bb);
903 tree mask = build_int_cst (pointer_sized_int_node,
904 tree_to_uhwi (align) - 1);
905 g = gimple_build_assign (make_ssa_name (pointer_sized_int_node),
906 BIT_AND_EXPR, check_align, mask);
907 gimple_set_location (g, loc);
908 if (check_null)
909 gsi_insert_after (&gsi2, g, GSI_NEW_STMT);
910 else
911 gsi_insert_before (&gsi, g, GSI_SAME_STMT);
913 g = gimple_build_cond (NE_EXPR, gimple_assign_lhs (g),
914 build_int_cst (pointer_sized_int_node, 0),
915 NULL_TREE, NULL_TREE);
916 gimple_set_location (g, loc);
917 if (check_null)
918 gsi_insert_after (&gsi2, g, GSI_NEW_STMT);
919 else
920 /* Replace the UBSAN_NULL with a GIMPLE_COND stmt. */
921 gsi_replace (&gsi, g, false);
923 return false;
926 #define OBJSZ_MAX_OFFSET (1024 * 16)
928 /* Expand UBSAN_OBJECT_SIZE internal call. */
930 bool
931 ubsan_expand_objsize_ifn (gimple_stmt_iterator *gsi)
933 gimple *stmt = gsi_stmt (*gsi);
934 location_t loc = gimple_location (stmt);
935 gcc_assert (gimple_call_num_args (stmt) == 4);
937 tree ptr = gimple_call_arg (stmt, 0);
938 tree offset = gimple_call_arg (stmt, 1);
939 tree size = gimple_call_arg (stmt, 2);
940 tree ckind = gimple_call_arg (stmt, 3);
941 gimple_stmt_iterator gsi_orig = *gsi;
942 gimple *g;
944 /* See if we can discard the check. */
945 if (TREE_CODE (size) != INTEGER_CST
946 || integer_all_onesp (size))
947 /* Yes, __builtin_object_size couldn't determine the
948 object size. */;
949 else if (TREE_CODE (offset) == INTEGER_CST
950 && wi::to_widest (offset) >= -OBJSZ_MAX_OFFSET
951 && wi::to_widest (offset) <= -1)
952 /* The offset is in range [-16K, -1]. */;
953 else
955 /* if (offset > objsize) */
956 basic_block then_bb, fallthru_bb;
957 gimple_stmt_iterator cond_insert_point
958 = create_cond_insert_point (gsi, false, false, true,
959 &then_bb, &fallthru_bb);
960 g = gimple_build_cond (GT_EXPR, offset, size, NULL_TREE, NULL_TREE);
961 gimple_set_location (g, loc);
962 gsi_insert_after (&cond_insert_point, g, GSI_NEW_STMT);
964 /* If the offset is small enough, we don't need the second
965 run-time check. */
966 if (TREE_CODE (offset) == INTEGER_CST
967 && wi::to_widest (offset) >= 0
968 && wi::to_widest (offset) <= OBJSZ_MAX_OFFSET)
969 *gsi = gsi_after_labels (then_bb);
970 else
972 /* Don't issue run-time error if (ptr > ptr + offset). That
973 may happen when computing a POINTER_PLUS_EXPR. */
974 basic_block then2_bb, fallthru2_bb;
976 gimple_stmt_iterator gsi2 = gsi_after_labels (then_bb);
977 cond_insert_point = create_cond_insert_point (&gsi2, false, false,
978 true, &then2_bb,
979 &fallthru2_bb);
980 /* Convert the pointer to an integer type. */
981 tree p = make_ssa_name (pointer_sized_int_node);
982 g = gimple_build_assign (p, NOP_EXPR, ptr);
983 gimple_set_location (g, loc);
984 gsi_insert_before (&cond_insert_point, g, GSI_NEW_STMT);
985 p = gimple_assign_lhs (g);
986 /* Compute ptr + offset. */
987 g = gimple_build_assign (make_ssa_name (pointer_sized_int_node),
988 PLUS_EXPR, p, offset);
989 gimple_set_location (g, loc);
990 gsi_insert_after (&cond_insert_point, g, GSI_NEW_STMT);
991 /* Now build the conditional and put it into the IR. */
992 g = gimple_build_cond (LE_EXPR, p, gimple_assign_lhs (g),
993 NULL_TREE, NULL_TREE);
994 gimple_set_location (g, loc);
995 gsi_insert_after (&cond_insert_point, g, GSI_NEW_STMT);
996 *gsi = gsi_after_labels (then2_bb);
999 /* Generate __ubsan_handle_type_mismatch call. */
1000 if (flag_sanitize_undefined_trap_on_error)
1001 g = gimple_build_call (builtin_decl_explicit (BUILT_IN_TRAP), 0);
1002 else
1004 tree data
1005 = ubsan_create_data ("__ubsan_objsz_data", 1, &loc,
1006 ubsan_type_descriptor (TREE_TYPE (ptr),
1007 UBSAN_PRINT_POINTER),
1008 NULL_TREE,
1009 build_zero_cst (unsigned_char_type_node),
1010 ckind,
1011 NULL_TREE);
1012 data = build_fold_addr_expr_loc (loc, data);
1013 enum built_in_function bcode
1014 = (flag_sanitize_recover & SANITIZE_OBJECT_SIZE)
1015 ? BUILT_IN_UBSAN_HANDLE_TYPE_MISMATCH_V1
1016 : BUILT_IN_UBSAN_HANDLE_TYPE_MISMATCH_V1_ABORT;
1017 tree p = make_ssa_name (pointer_sized_int_node);
1018 g = gimple_build_assign (p, NOP_EXPR, ptr);
1019 gimple_set_location (g, loc);
1020 gsi_insert_before (gsi, g, GSI_SAME_STMT);
1021 g = gimple_build_call (builtin_decl_explicit (bcode), 2, data, p);
1023 gimple_set_location (g, loc);
1024 gsi_insert_before (gsi, g, GSI_SAME_STMT);
1026 /* Point GSI to next logical statement. */
1027 *gsi = gsi_start_bb (fallthru_bb);
1029 /* Get rid of the UBSAN_OBJECT_SIZE call from the IR. */
1030 unlink_stmt_vdef (stmt);
1031 gsi_remove (&gsi_orig, true);
1032 return true;
1035 /* Get rid of the UBSAN_OBJECT_SIZE call from the IR. */
1036 unlink_stmt_vdef (stmt);
1037 gsi_remove (gsi, true);
1038 return true;
1041 /* Expand UBSAN_PTR internal call. */
1043 bool
1044 ubsan_expand_ptr_ifn (gimple_stmt_iterator *gsip)
1046 gimple_stmt_iterator gsi = *gsip;
1047 gimple *stmt = gsi_stmt (gsi);
1048 location_t loc = gimple_location (stmt);
1049 gcc_assert (gimple_call_num_args (stmt) == 2);
1050 tree ptr = gimple_call_arg (stmt, 0);
1051 tree off = gimple_call_arg (stmt, 1);
1053 if (integer_zerop (off))
1055 gsi_remove (gsip, true);
1056 unlink_stmt_vdef (stmt);
1057 return true;
1060 basic_block cur_bb = gsi_bb (gsi);
1061 tree ptrplusoff = make_ssa_name (pointer_sized_int_node);
1062 tree ptri = make_ssa_name (pointer_sized_int_node);
1063 int pos_neg = get_range_pos_neg (off);
1065 /* Split the original block holding the pointer dereference. */
1066 edge e = split_block (cur_bb, stmt);
1068 /* Get a hold on the 'condition block', the 'then block' and the
1069 'else block'. */
1070 basic_block cond_bb = e->src;
1071 basic_block fallthru_bb = e->dest;
1072 basic_block then_bb = create_empty_bb (cond_bb);
1073 basic_block cond_pos_bb = NULL, cond_neg_bb = NULL;
1074 add_bb_to_loop (then_bb, cond_bb->loop_father);
1075 loops_state_set (LOOPS_NEED_FIXUP);
1077 /* Set up the fallthrough basic block. */
1078 e->flags = EDGE_FALSE_VALUE;
1079 if (pos_neg != 3)
1081 e->probability = profile_probability::very_likely ();
1083 /* Connect 'then block' with the 'else block'. This is needed
1084 as the ubsan routines we call in the 'then block' are not noreturn.
1085 The 'then block' only has one outcoming edge. */
1086 make_single_succ_edge (then_bb, fallthru_bb, EDGE_FALLTHRU);
1088 /* Make an edge coming from the 'cond block' into the 'then block';
1089 this edge is unlikely taken, so set up the probability
1090 accordingly. */
1091 e = make_edge (cond_bb, then_bb, EDGE_TRUE_VALUE);
1092 e->probability = profile_probability::very_unlikely ();
1093 then_bb->count = e->count ();
1095 else
1097 e->probability = profile_probability::even ();
1099 e = split_block (fallthru_bb, (gimple *) NULL);
1100 cond_neg_bb = e->src;
1101 fallthru_bb = e->dest;
1102 e->probability = profile_probability::very_likely ();
1103 e->flags = EDGE_FALSE_VALUE;
1105 e = make_edge (cond_neg_bb, then_bb, EDGE_TRUE_VALUE);
1106 e->probability = profile_probability::very_unlikely ();
1107 then_bb->count = e->count ();
1109 cond_pos_bb = create_empty_bb (cond_bb);
1110 add_bb_to_loop (cond_pos_bb, cond_bb->loop_father);
1112 e = make_edge (cond_bb, cond_pos_bb, EDGE_TRUE_VALUE);
1113 e->probability = profile_probability::even ();
1114 cond_pos_bb->count = e->count ();
1116 e = make_edge (cond_pos_bb, then_bb, EDGE_TRUE_VALUE);
1117 e->probability = profile_probability::very_unlikely ();
1119 e = make_edge (cond_pos_bb, fallthru_bb, EDGE_FALSE_VALUE);
1120 e->probability = profile_probability::very_likely ();
1122 make_single_succ_edge (then_bb, fallthru_bb, EDGE_FALLTHRU);
1125 gimple *g = gimple_build_assign (ptri, NOP_EXPR, ptr);
1126 gimple_set_location (g, loc);
1127 gsi_insert_before (&gsi, g, GSI_SAME_STMT);
1128 g = gimple_build_assign (ptrplusoff, PLUS_EXPR, ptri, off);
1129 gimple_set_location (g, loc);
1130 gsi_insert_before (&gsi, g, GSI_SAME_STMT);
1132 /* Update dominance info for the newly created then_bb; note that
1133 fallthru_bb's dominance info has already been updated by
1134 split_block. */
1135 if (dom_info_available_p (CDI_DOMINATORS))
1137 set_immediate_dominator (CDI_DOMINATORS, then_bb, cond_bb);
1138 if (pos_neg == 3)
1140 set_immediate_dominator (CDI_DOMINATORS, cond_pos_bb, cond_bb);
1141 set_immediate_dominator (CDI_DOMINATORS, fallthru_bb, cond_bb);
1145 /* Put the ubsan builtin call into the newly created BB. */
1146 if (flag_sanitize_undefined_trap_on_error)
1147 g = gimple_build_call (builtin_decl_implicit (BUILT_IN_TRAP), 0);
1148 else
1150 enum built_in_function bcode
1151 = (flag_sanitize_recover & SANITIZE_POINTER_OVERFLOW)
1152 ? BUILT_IN_UBSAN_HANDLE_POINTER_OVERFLOW
1153 : BUILT_IN_UBSAN_HANDLE_POINTER_OVERFLOW_ABORT;
1154 tree fn = builtin_decl_implicit (bcode);
1155 tree data
1156 = ubsan_create_data ("__ubsan_ptrovf_data", 1, &loc,
1157 NULL_TREE, NULL_TREE);
1158 data = build_fold_addr_expr_loc (loc, data);
1159 g = gimple_build_call (fn, 3, data, ptr, ptrplusoff);
1161 gimple_stmt_iterator gsi2 = gsi_start_bb (then_bb);
1162 gimple_set_location (g, loc);
1163 gsi_insert_after (&gsi2, g, GSI_NEW_STMT);
1165 /* Unlink the UBSAN_PTRs vops before replacing it. */
1166 unlink_stmt_vdef (stmt);
1168 if (TREE_CODE (off) == INTEGER_CST)
1169 g = gimple_build_cond (wi::neg_p (wi::to_wide (off)) ? LT_EXPR : GE_EXPR,
1170 ptri, fold_build1 (NEGATE_EXPR, sizetype, off),
1171 NULL_TREE, NULL_TREE);
1172 else if (pos_neg != 3)
1173 g = gimple_build_cond (pos_neg == 1 ? LT_EXPR : GT_EXPR,
1174 ptrplusoff, ptri, NULL_TREE, NULL_TREE);
1175 else
1177 gsi2 = gsi_start_bb (cond_pos_bb);
1178 g = gimple_build_cond (LT_EXPR, ptrplusoff, ptri, NULL_TREE, NULL_TREE);
1179 gimple_set_location (g, loc);
1180 gsi_insert_after (&gsi2, g, GSI_NEW_STMT);
1182 gsi2 = gsi_start_bb (cond_neg_bb);
1183 g = gimple_build_cond (GT_EXPR, ptrplusoff, ptri, NULL_TREE, NULL_TREE);
1184 gimple_set_location (g, loc);
1185 gsi_insert_after (&gsi2, g, GSI_NEW_STMT);
1187 gimple_seq seq = NULL;
1188 tree t = gimple_build (&seq, loc, NOP_EXPR, ssizetype, off);
1189 t = gimple_build (&seq, loc, GE_EXPR, boolean_type_node,
1190 t, ssize_int (0));
1191 gsi_insert_seq_before (&gsi, seq, GSI_SAME_STMT);
1192 g = gimple_build_cond (NE_EXPR, t, boolean_false_node,
1193 NULL_TREE, NULL_TREE);
1195 gimple_set_location (g, loc);
1196 /* Replace the UBSAN_PTR with a GIMPLE_COND stmt. */
1197 gsi_replace (&gsi, g, false);
1198 return false;
1202 /* Cached __ubsan_vptr_type_cache decl. */
1203 static GTY(()) tree ubsan_vptr_type_cache_decl;
1205 /* Expand UBSAN_VPTR internal call. The type is kept on the ckind
1206 argument which is a constant, because the middle-end treats pointer
1207 conversions as useless and therefore the type of the first argument
1208 could be changed to any other pointer type. */
1210 bool
1211 ubsan_expand_vptr_ifn (gimple_stmt_iterator *gsip)
1213 gimple_stmt_iterator gsi = *gsip;
1214 gimple *stmt = gsi_stmt (gsi);
1215 location_t loc = gimple_location (stmt);
1216 gcc_assert (gimple_call_num_args (stmt) == 5);
1217 tree op = gimple_call_arg (stmt, 0);
1218 tree vptr = gimple_call_arg (stmt, 1);
1219 tree str_hash = gimple_call_arg (stmt, 2);
1220 tree ti_decl_addr = gimple_call_arg (stmt, 3);
1221 tree ckind_tree = gimple_call_arg (stmt, 4);
1222 ubsan_null_ckind ckind = (ubsan_null_ckind) tree_to_uhwi (ckind_tree);
1223 tree type = TREE_TYPE (TREE_TYPE (ckind_tree));
1224 gimple *g;
1225 basic_block fallthru_bb = NULL;
1227 if (ckind == UBSAN_DOWNCAST_POINTER)
1229 /* Guard everything with if (op != NULL) { ... }. */
1230 basic_block then_bb;
1231 gimple_stmt_iterator cond_insert_point
1232 = create_cond_insert_point (gsip, false, false, true,
1233 &then_bb, &fallthru_bb);
1234 g = gimple_build_cond (NE_EXPR, op, build_zero_cst (TREE_TYPE (op)),
1235 NULL_TREE, NULL_TREE);
1236 gimple_set_location (g, loc);
1237 gsi_insert_after (&cond_insert_point, g, GSI_NEW_STMT);
1238 *gsip = gsi_after_labels (then_bb);
1239 gsi_remove (&gsi, false);
1240 gsi_insert_before (gsip, stmt, GSI_NEW_STMT);
1241 gsi = *gsip;
1244 tree htype = TREE_TYPE (str_hash);
1245 tree cst = wide_int_to_tree (htype,
1246 wi::uhwi (((uint64_t) 0x9ddfea08 << 32)
1247 | 0xeb382d69, 64));
1248 g = gimple_build_assign (make_ssa_name (htype), BIT_XOR_EXPR,
1249 vptr, str_hash);
1250 gimple_set_location (g, loc);
1251 gsi_insert_before (gsip, g, GSI_SAME_STMT);
1252 g = gimple_build_assign (make_ssa_name (htype), MULT_EXPR,
1253 gimple_assign_lhs (g), cst);
1254 gimple_set_location (g, loc);
1255 gsi_insert_before (gsip, g, GSI_SAME_STMT);
1256 tree t1 = gimple_assign_lhs (g);
1257 g = gimple_build_assign (make_ssa_name (htype), LSHIFT_EXPR,
1258 t1, build_int_cst (integer_type_node, 47));
1259 gimple_set_location (g, loc);
1260 tree t2 = gimple_assign_lhs (g);
1261 gsi_insert_before (gsip, g, GSI_SAME_STMT);
1262 g = gimple_build_assign (make_ssa_name (htype), BIT_XOR_EXPR,
1263 vptr, t1);
1264 gimple_set_location (g, loc);
1265 gsi_insert_before (gsip, g, GSI_SAME_STMT);
1266 g = gimple_build_assign (make_ssa_name (htype), BIT_XOR_EXPR,
1267 t2, gimple_assign_lhs (g));
1268 gimple_set_location (g, loc);
1269 gsi_insert_before (gsip, g, GSI_SAME_STMT);
1270 g = gimple_build_assign (make_ssa_name (htype), MULT_EXPR,
1271 gimple_assign_lhs (g), cst);
1272 gimple_set_location (g, loc);
1273 gsi_insert_before (gsip, g, GSI_SAME_STMT);
1274 tree t3 = gimple_assign_lhs (g);
1275 g = gimple_build_assign (make_ssa_name (htype), LSHIFT_EXPR,
1276 t3, build_int_cst (integer_type_node, 47));
1277 gimple_set_location (g, loc);
1278 gsi_insert_before (gsip, g, GSI_SAME_STMT);
1279 g = gimple_build_assign (make_ssa_name (htype), BIT_XOR_EXPR,
1280 t3, gimple_assign_lhs (g));
1281 gimple_set_location (g, loc);
1282 gsi_insert_before (gsip, g, GSI_SAME_STMT);
1283 g = gimple_build_assign (make_ssa_name (htype), MULT_EXPR,
1284 gimple_assign_lhs (g), cst);
1285 gimple_set_location (g, loc);
1286 gsi_insert_before (gsip, g, GSI_SAME_STMT);
1287 if (!useless_type_conversion_p (pointer_sized_int_node, htype))
1289 g = gimple_build_assign (make_ssa_name (pointer_sized_int_node),
1290 NOP_EXPR, gimple_assign_lhs (g));
1291 gimple_set_location (g, loc);
1292 gsi_insert_before (gsip, g, GSI_SAME_STMT);
1294 tree hash = gimple_assign_lhs (g);
1296 if (ubsan_vptr_type_cache_decl == NULL_TREE)
1298 tree atype = build_array_type_nelts (pointer_sized_int_node, 128);
1299 tree array = build_decl (UNKNOWN_LOCATION, VAR_DECL,
1300 get_identifier ("__ubsan_vptr_type_cache"),
1301 atype);
1302 DECL_ARTIFICIAL (array) = 1;
1303 DECL_IGNORED_P (array) = 1;
1304 TREE_PUBLIC (array) = 1;
1305 TREE_STATIC (array) = 1;
1306 DECL_EXTERNAL (array) = 1;
1307 DECL_VISIBILITY (array) = VISIBILITY_DEFAULT;
1308 DECL_VISIBILITY_SPECIFIED (array) = 1;
1309 varpool_node::finalize_decl (array);
1310 ubsan_vptr_type_cache_decl = array;
1313 g = gimple_build_assign (make_ssa_name (pointer_sized_int_node),
1314 BIT_AND_EXPR, hash,
1315 build_int_cst (pointer_sized_int_node, 127));
1316 gimple_set_location (g, loc);
1317 gsi_insert_before (gsip, g, GSI_SAME_STMT);
1319 tree c = build4_loc (loc, ARRAY_REF, pointer_sized_int_node,
1320 ubsan_vptr_type_cache_decl, gimple_assign_lhs (g),
1321 NULL_TREE, NULL_TREE);
1322 g = gimple_build_assign (make_ssa_name (pointer_sized_int_node),
1323 ARRAY_REF, c);
1324 gimple_set_location (g, loc);
1325 gsi_insert_before (gsip, g, GSI_SAME_STMT);
1327 basic_block then_bb, fallthru2_bb;
1328 gimple_stmt_iterator cond_insert_point
1329 = create_cond_insert_point (gsip, false, false, true,
1330 &then_bb, &fallthru2_bb);
1331 g = gimple_build_cond (NE_EXPR, gimple_assign_lhs (g), hash,
1332 NULL_TREE, NULL_TREE);
1333 gimple_set_location (g, loc);
1334 gsi_insert_after (&cond_insert_point, g, GSI_NEW_STMT);
1335 *gsip = gsi_after_labels (then_bb);
1336 if (fallthru_bb == NULL)
1337 fallthru_bb = fallthru2_bb;
1339 tree data
1340 = ubsan_create_data ("__ubsan_vptr_data", 1, &loc,
1341 ubsan_type_descriptor (type), NULL_TREE, ti_decl_addr,
1342 build_int_cst (unsigned_char_type_node, ckind),
1343 NULL_TREE);
1344 data = build_fold_addr_expr_loc (loc, data);
1345 enum built_in_function bcode
1346 = (flag_sanitize_recover & SANITIZE_VPTR)
1347 ? BUILT_IN_UBSAN_HANDLE_DYNAMIC_TYPE_CACHE_MISS
1348 : BUILT_IN_UBSAN_HANDLE_DYNAMIC_TYPE_CACHE_MISS_ABORT;
1350 g = gimple_build_call (builtin_decl_explicit (bcode), 3, data, op, hash);
1351 gimple_set_location (g, loc);
1352 gsi_insert_before (gsip, g, GSI_SAME_STMT);
1354 /* Point GSI to next logical statement. */
1355 *gsip = gsi_start_bb (fallthru_bb);
1357 /* Get rid of the UBSAN_VPTR call from the IR. */
1358 unlink_stmt_vdef (stmt);
1359 gsi_remove (&gsi, true);
1360 return true;
1363 /* Instrument a memory reference. BASE is the base of MEM, IS_LHS says
1364 whether the pointer is on the left hand side of the assignment. */
1366 static void
1367 instrument_mem_ref (tree mem, tree base, gimple_stmt_iterator *iter,
1368 bool is_lhs)
1370 enum ubsan_null_ckind ikind = is_lhs ? UBSAN_STORE_OF : UBSAN_LOAD_OF;
1371 unsigned int align = 0;
1372 if (sanitize_flags_p (SANITIZE_ALIGNMENT))
1374 align = min_align_of_type (TREE_TYPE (base));
1375 if (align <= 1)
1376 align = 0;
1378 if (align == 0 && !sanitize_flags_p (SANITIZE_NULL))
1379 return;
1380 tree t = TREE_OPERAND (base, 0);
1381 if (!POINTER_TYPE_P (TREE_TYPE (t)))
1382 return;
1383 if (RECORD_OR_UNION_TYPE_P (TREE_TYPE (base)) && mem != base)
1384 ikind = UBSAN_MEMBER_ACCESS;
1385 tree kind = build_int_cst (build_pointer_type (TREE_TYPE (base)), ikind);
1386 tree alignt = build_int_cst (pointer_sized_int_node, align);
1387 gcall *g = gimple_build_call_internal (IFN_UBSAN_NULL, 3, t, kind, alignt);
1388 gimple_set_location (g, gimple_location (gsi_stmt (*iter)));
1389 gsi_insert_before (iter, g, GSI_SAME_STMT);
1392 /* Perform the pointer instrumentation. */
1394 static void
1395 instrument_null (gimple_stmt_iterator gsi, tree t, bool is_lhs)
1397 /* Handle also e.g. &s->i. */
1398 if (TREE_CODE (t) == ADDR_EXPR)
1399 t = TREE_OPERAND (t, 0);
1400 tree base = get_base_address (t);
1401 if (base != NULL_TREE
1402 && TREE_CODE (base) == MEM_REF
1403 && TREE_CODE (TREE_OPERAND (base, 0)) == SSA_NAME)
1404 instrument_mem_ref (t, base, &gsi, is_lhs);
1407 /* Instrument pointer arithmetics PTR p+ OFF. */
1409 static void
1410 instrument_pointer_overflow (gimple_stmt_iterator *gsi, tree ptr, tree off)
1412 if (TYPE_PRECISION (sizetype) != POINTER_SIZE)
1413 return;
1414 gcall *g = gimple_build_call_internal (IFN_UBSAN_PTR, 2, ptr, off);
1415 gimple_set_location (g, gimple_location (gsi_stmt (*gsi)));
1416 gsi_insert_before (gsi, g, GSI_SAME_STMT);
1419 /* Instrument pointer arithmetics if any. */
1421 static void
1422 maybe_instrument_pointer_overflow (gimple_stmt_iterator *gsi, tree t)
1424 if (TYPE_PRECISION (sizetype) != POINTER_SIZE)
1425 return;
1427 /* Handle also e.g. &s->i. */
1428 if (TREE_CODE (t) == ADDR_EXPR)
1429 t = TREE_OPERAND (t, 0);
1431 if (!handled_component_p (t) && TREE_CODE (t) != MEM_REF)
1432 return;
1434 poly_int64 bitsize, bitpos, bytepos;
1435 tree offset;
1436 machine_mode mode;
1437 int volatilep = 0, reversep, unsignedp = 0;
1438 tree inner = get_inner_reference (t, &bitsize, &bitpos, &offset, &mode,
1439 &unsignedp, &reversep, &volatilep);
1440 tree moff = NULL_TREE;
1442 bool decl_p = DECL_P (inner);
1443 tree base;
1444 if (decl_p)
1446 if ((VAR_P (inner)
1447 || TREE_CODE (inner) == PARM_DECL
1448 || TREE_CODE (inner) == RESULT_DECL)
1449 && DECL_REGISTER (inner))
1450 return;
1451 base = inner;
1452 /* If BASE is a fixed size automatic variable or
1453 global variable defined in the current TU and bitpos
1454 fits, don't instrument anything. */
1455 poly_int64 base_size;
1456 if (offset == NULL_TREE
1457 && maybe_ne (bitpos, 0)
1458 && (VAR_P (base)
1459 || TREE_CODE (base) == PARM_DECL
1460 || TREE_CODE (base) == RESULT_DECL)
1461 && poly_int_tree_p (DECL_SIZE (base), &base_size)
1462 && known_ge (base_size, bitpos)
1463 && (!is_global_var (base) || decl_binds_to_current_def_p (base)))
1464 return;
1466 else if (TREE_CODE (inner) == MEM_REF)
1468 base = TREE_OPERAND (inner, 0);
1469 if (TREE_CODE (base) == ADDR_EXPR
1470 && DECL_P (TREE_OPERAND (base, 0))
1471 && !TREE_ADDRESSABLE (TREE_OPERAND (base, 0))
1472 && !is_global_var (TREE_OPERAND (base, 0)))
1473 return;
1474 moff = TREE_OPERAND (inner, 1);
1475 if (integer_zerop (moff))
1476 moff = NULL_TREE;
1478 else
1479 return;
1481 if (!POINTER_TYPE_P (TREE_TYPE (base)) && !DECL_P (base))
1482 return;
1483 bytepos = bits_to_bytes_round_down (bitpos);
1484 if (offset == NULL_TREE && known_eq (bytepos, 0) && moff == NULL_TREE)
1485 return;
1487 tree base_addr = base;
1488 if (decl_p)
1489 base_addr = build1 (ADDR_EXPR,
1490 build_pointer_type (TREE_TYPE (base)), base);
1491 t = offset;
1492 if (maybe_ne (bytepos, 0))
1494 if (t)
1495 t = fold_build2 (PLUS_EXPR, TREE_TYPE (t), t,
1496 build_int_cst (TREE_TYPE (t), bytepos));
1497 else
1498 t = size_int (bytepos);
1500 if (moff)
1502 if (t)
1503 t = fold_build2 (PLUS_EXPR, TREE_TYPE (t), t,
1504 fold_convert (TREE_TYPE (t), moff));
1505 else
1506 t = fold_convert (sizetype, moff);
1508 t = force_gimple_operand_gsi (gsi, t, true, NULL_TREE, true,
1509 GSI_SAME_STMT);
1510 base_addr = force_gimple_operand_gsi (gsi, base_addr, true, NULL_TREE, true,
1511 GSI_SAME_STMT);
1512 instrument_pointer_overflow (gsi, base_addr, t);
1515 /* Build an ubsan builtin call for the signed-integer-overflow
1516 sanitization. CODE says what kind of builtin are we building,
1517 LOC is a location, LHSTYPE is the type of LHS, OP0 and OP1
1518 are operands of the binary operation. */
1520 tree
1521 ubsan_build_overflow_builtin (tree_code code, location_t loc, tree lhstype,
1522 tree op0, tree op1, tree *datap)
1524 if (flag_sanitize_undefined_trap_on_error)
1525 return build_call_expr_loc (loc, builtin_decl_explicit (BUILT_IN_TRAP), 0);
1527 tree data;
1528 if (datap && *datap)
1529 data = *datap;
1530 else
1531 data = ubsan_create_data ("__ubsan_overflow_data", 1, &loc,
1532 ubsan_type_descriptor (lhstype), NULL_TREE,
1533 NULL_TREE);
1534 if (datap)
1535 *datap = data;
1536 enum built_in_function fn_code;
1538 switch (code)
1540 case PLUS_EXPR:
1541 fn_code = (flag_sanitize_recover & SANITIZE_SI_OVERFLOW)
1542 ? BUILT_IN_UBSAN_HANDLE_ADD_OVERFLOW
1543 : BUILT_IN_UBSAN_HANDLE_ADD_OVERFLOW_ABORT;
1544 break;
1545 case MINUS_EXPR:
1546 fn_code = (flag_sanitize_recover & SANITIZE_SI_OVERFLOW)
1547 ? BUILT_IN_UBSAN_HANDLE_SUB_OVERFLOW
1548 : BUILT_IN_UBSAN_HANDLE_SUB_OVERFLOW_ABORT;
1549 break;
1550 case MULT_EXPR:
1551 fn_code = (flag_sanitize_recover & SANITIZE_SI_OVERFLOW)
1552 ? BUILT_IN_UBSAN_HANDLE_MUL_OVERFLOW
1553 : BUILT_IN_UBSAN_HANDLE_MUL_OVERFLOW_ABORT;
1554 break;
1555 case NEGATE_EXPR:
1556 fn_code = (flag_sanitize_recover & SANITIZE_SI_OVERFLOW)
1557 ? BUILT_IN_UBSAN_HANDLE_NEGATE_OVERFLOW
1558 : BUILT_IN_UBSAN_HANDLE_NEGATE_OVERFLOW_ABORT;
1559 break;
1560 default:
1561 gcc_unreachable ();
1563 tree fn = builtin_decl_explicit (fn_code);
1564 return build_call_expr_loc (loc, fn, 2 + (code != NEGATE_EXPR),
1565 build_fold_addr_expr_loc (loc, data),
1566 ubsan_encode_value (op0, UBSAN_ENCODE_VALUE_RTL),
1568 ? ubsan_encode_value (op1,
1569 UBSAN_ENCODE_VALUE_RTL)
1570 : NULL_TREE);
1573 /* Perform the signed integer instrumentation. GSI is the iterator
1574 pointing at statement we are trying to instrument. */
1576 static void
1577 instrument_si_overflow (gimple_stmt_iterator gsi)
1579 gimple *stmt = gsi_stmt (gsi);
1580 tree_code code = gimple_assign_rhs_code (stmt);
1581 tree lhs = gimple_assign_lhs (stmt);
1582 tree lhstype = TREE_TYPE (lhs);
1583 tree lhsinner = VECTOR_TYPE_P (lhstype) ? TREE_TYPE (lhstype) : lhstype;
1584 tree a, b;
1585 gimple *g;
1587 /* If this is not a signed operation, don't instrument anything here.
1588 Also punt on bit-fields. */
1589 if (!INTEGRAL_TYPE_P (lhsinner)
1590 || TYPE_OVERFLOW_WRAPS (lhsinner)
1591 || maybe_ne (GET_MODE_BITSIZE (TYPE_MODE (lhsinner)),
1592 TYPE_PRECISION (lhsinner)))
1593 return;
1595 switch (code)
1597 case MINUS_EXPR:
1598 case PLUS_EXPR:
1599 case MULT_EXPR:
1600 /* Transform
1601 i = u {+,-,*} 5;
1602 into
1603 i = UBSAN_CHECK_{ADD,SUB,MUL} (u, 5); */
1604 a = gimple_assign_rhs1 (stmt);
1605 b = gimple_assign_rhs2 (stmt);
1606 g = gimple_build_call_internal (code == PLUS_EXPR
1607 ? IFN_UBSAN_CHECK_ADD
1608 : code == MINUS_EXPR
1609 ? IFN_UBSAN_CHECK_SUB
1610 : IFN_UBSAN_CHECK_MUL, 2, a, b);
1611 gimple_call_set_lhs (g, lhs);
1612 gsi_replace (&gsi, g, true);
1613 break;
1614 case NEGATE_EXPR:
1615 /* Represent i = -u;
1617 i = UBSAN_CHECK_SUB (0, u); */
1618 a = build_zero_cst (lhstype);
1619 b = gimple_assign_rhs1 (stmt);
1620 g = gimple_build_call_internal (IFN_UBSAN_CHECK_SUB, 2, a, b);
1621 gimple_call_set_lhs (g, lhs);
1622 gsi_replace (&gsi, g, true);
1623 break;
1624 case ABS_EXPR:
1625 /* Transform i = ABS_EXPR<u>;
1626 into
1627 _N = UBSAN_CHECK_SUB (0, u);
1628 i = ABS_EXPR<_N>; */
1629 a = build_zero_cst (lhstype);
1630 b = gimple_assign_rhs1 (stmt);
1631 g = gimple_build_call_internal (IFN_UBSAN_CHECK_SUB, 2, a, b);
1632 a = make_ssa_name (lhstype);
1633 gimple_call_set_lhs (g, a);
1634 gimple_set_location (g, gimple_location (stmt));
1635 gsi_insert_before (&gsi, g, GSI_SAME_STMT);
1636 gimple_assign_set_rhs1 (stmt, a);
1637 update_stmt (stmt);
1638 break;
1639 default:
1640 break;
1644 /* Instrument loads from (non-bitfield) bool and C++ enum values
1645 to check if the memory value is outside of the range of the valid
1646 type values. */
1648 static void
1649 instrument_bool_enum_load (gimple_stmt_iterator *gsi)
1651 gimple *stmt = gsi_stmt (*gsi);
1652 tree rhs = gimple_assign_rhs1 (stmt);
1653 tree type = TREE_TYPE (rhs);
1654 tree minv = NULL_TREE, maxv = NULL_TREE;
1656 if (TREE_CODE (type) == BOOLEAN_TYPE
1657 && sanitize_flags_p (SANITIZE_BOOL))
1659 minv = boolean_false_node;
1660 maxv = boolean_true_node;
1662 else if (TREE_CODE (type) == ENUMERAL_TYPE
1663 && sanitize_flags_p (SANITIZE_ENUM)
1664 && TREE_TYPE (type) != NULL_TREE
1665 && TREE_CODE (TREE_TYPE (type)) == INTEGER_TYPE
1666 && (TYPE_PRECISION (TREE_TYPE (type))
1667 < GET_MODE_PRECISION (SCALAR_INT_TYPE_MODE (type))))
1669 minv = TYPE_MIN_VALUE (TREE_TYPE (type));
1670 maxv = TYPE_MAX_VALUE (TREE_TYPE (type));
1672 else
1673 return;
1675 int modebitsize = GET_MODE_BITSIZE (SCALAR_INT_TYPE_MODE (type));
1676 poly_int64 bitsize, bitpos;
1677 tree offset;
1678 machine_mode mode;
1679 int volatilep = 0, reversep, unsignedp = 0;
1680 tree base = get_inner_reference (rhs, &bitsize, &bitpos, &offset, &mode,
1681 &unsignedp, &reversep, &volatilep);
1682 tree utype = build_nonstandard_integer_type (modebitsize, 1);
1684 if ((VAR_P (base) && DECL_HARD_REGISTER (base))
1685 || !multiple_p (bitpos, modebitsize)
1686 || maybe_ne (bitsize, modebitsize)
1687 || GET_MODE_BITSIZE (SCALAR_INT_TYPE_MODE (utype)) != modebitsize
1688 || TREE_CODE (gimple_assign_lhs (stmt)) != SSA_NAME)
1689 return;
1691 bool ends_bb = stmt_ends_bb_p (stmt);
1692 location_t loc = gimple_location (stmt);
1693 tree lhs = gimple_assign_lhs (stmt);
1694 tree ptype = build_pointer_type (TREE_TYPE (rhs));
1695 tree atype = reference_alias_ptr_type (rhs);
1696 gimple *g = gimple_build_assign (make_ssa_name (ptype),
1697 build_fold_addr_expr (rhs));
1698 gimple_set_location (g, loc);
1699 gsi_insert_before (gsi, g, GSI_SAME_STMT);
1700 tree mem = build2 (MEM_REF, utype, gimple_assign_lhs (g),
1701 build_int_cst (atype, 0));
1702 tree urhs = make_ssa_name (utype);
1703 if (ends_bb)
1705 gimple_assign_set_lhs (stmt, urhs);
1706 g = gimple_build_assign (lhs, NOP_EXPR, urhs);
1707 gimple_set_location (g, loc);
1708 edge e = find_fallthru_edge (gimple_bb (stmt)->succs);
1709 gsi_insert_on_edge_immediate (e, g);
1710 gimple_assign_set_rhs_from_tree (gsi, mem);
1711 update_stmt (stmt);
1712 *gsi = gsi_for_stmt (g);
1713 g = stmt;
1715 else
1717 g = gimple_build_assign (urhs, mem);
1718 gimple_set_location (g, loc);
1719 gsi_insert_before (gsi, g, GSI_SAME_STMT);
1721 minv = fold_convert (utype, minv);
1722 maxv = fold_convert (utype, maxv);
1723 if (!integer_zerop (minv))
1725 g = gimple_build_assign (make_ssa_name (utype), MINUS_EXPR, urhs, minv);
1726 gimple_set_location (g, loc);
1727 gsi_insert_before (gsi, g, GSI_SAME_STMT);
1730 gimple_stmt_iterator gsi2 = *gsi;
1731 basic_block then_bb, fallthru_bb;
1732 *gsi = create_cond_insert_point (gsi, true, false, true,
1733 &then_bb, &fallthru_bb);
1734 g = gimple_build_cond (GT_EXPR, gimple_assign_lhs (g),
1735 int_const_binop (MINUS_EXPR, maxv, minv),
1736 NULL_TREE, NULL_TREE);
1737 gimple_set_location (g, loc);
1738 gsi_insert_after (gsi, g, GSI_NEW_STMT);
1740 if (!ends_bb)
1742 gimple_assign_set_rhs_with_ops (&gsi2, NOP_EXPR, urhs);
1743 update_stmt (stmt);
1746 gsi2 = gsi_after_labels (then_bb);
1747 if (flag_sanitize_undefined_trap_on_error)
1748 g = gimple_build_call (builtin_decl_explicit (BUILT_IN_TRAP), 0);
1749 else
1751 tree data = ubsan_create_data ("__ubsan_invalid_value_data", 1, &loc,
1752 ubsan_type_descriptor (type), NULL_TREE,
1753 NULL_TREE);
1754 data = build_fold_addr_expr_loc (loc, data);
1755 enum built_in_function bcode
1756 = (flag_sanitize_recover & (TREE_CODE (type) == BOOLEAN_TYPE
1757 ? SANITIZE_BOOL : SANITIZE_ENUM))
1758 ? BUILT_IN_UBSAN_HANDLE_LOAD_INVALID_VALUE
1759 : BUILT_IN_UBSAN_HANDLE_LOAD_INVALID_VALUE_ABORT;
1760 tree fn = builtin_decl_explicit (bcode);
1762 tree val = ubsan_encode_value (urhs, UBSAN_ENCODE_VALUE_GIMPLE);
1763 val = force_gimple_operand_gsi (&gsi2, val, true, NULL_TREE, true,
1764 GSI_SAME_STMT);
1765 g = gimple_build_call (fn, 2, data, val);
1767 gimple_set_location (g, loc);
1768 gsi_insert_before (&gsi2, g, GSI_SAME_STMT);
1769 ubsan_create_edge (g);
1770 *gsi = gsi_for_stmt (stmt);
1773 /* Determine if we can propagate given LOCATION to ubsan_data descriptor to use
1774 new style handlers. Libubsan uses heuristics to destinguish between old and
1775 new styles and relies on these properties for filename:
1777 a) Location's filename must not be NULL.
1778 b) Location's filename must not be equal to "".
1779 c) Location's filename must not be equal to "\1".
1780 d) First two bytes of filename must not contain '\xff' symbol. */
1782 static bool
1783 ubsan_use_new_style_p (location_t loc)
1785 if (loc == UNKNOWN_LOCATION)
1786 return false;
1788 expanded_location xloc = expand_location (loc);
1789 if (xloc.file == NULL || startswith (xloc.file, "\1")
1790 || xloc.file[0] == '\0' || xloc.file[0] == '\xff'
1791 || xloc.file[1] == '\xff')
1792 return false;
1794 return true;
1797 /* Instrument float point-to-integer conversion. TYPE is an integer type of
1798 destination, EXPR is floating-point expression. */
1800 tree
1801 ubsan_instrument_float_cast (location_t loc, tree type, tree expr)
1803 tree expr_type = TREE_TYPE (expr);
1804 tree t, tt, fn, min, max;
1805 machine_mode mode = TYPE_MODE (expr_type);
1806 int prec = TYPE_PRECISION (type);
1807 bool uns_p = TYPE_UNSIGNED (type);
1808 if (loc == UNKNOWN_LOCATION)
1809 loc = input_location;
1811 /* Float to integer conversion first truncates toward zero, so
1812 even signed char c = 127.875f; is not problematic.
1813 Therefore, we should complain only if EXPR is unordered or smaller
1814 or equal than TYPE_MIN_VALUE - 1.0 or greater or equal than
1815 TYPE_MAX_VALUE + 1.0. */
1816 if (REAL_MODE_FORMAT (mode)->b == 2)
1818 /* For maximum, TYPE_MAX_VALUE might not be representable
1819 in EXPR_TYPE, e.g. if TYPE is 64-bit long long and
1820 EXPR_TYPE is IEEE single float, but TYPE_MAX_VALUE + 1.0 is
1821 either representable or infinity. */
1822 REAL_VALUE_TYPE maxval = dconst1;
1823 SET_REAL_EXP (&maxval, REAL_EXP (&maxval) + prec - !uns_p);
1824 real_convert (&maxval, mode, &maxval);
1825 max = build_real (expr_type, maxval);
1827 /* For unsigned, assume -1.0 is always representable. */
1828 if (uns_p)
1829 min = build_minus_one_cst (expr_type);
1830 else
1832 /* TYPE_MIN_VALUE is generally representable (or -inf),
1833 but TYPE_MIN_VALUE - 1.0 might not be. */
1834 REAL_VALUE_TYPE minval = dconstm1, minval2;
1835 SET_REAL_EXP (&minval, REAL_EXP (&minval) + prec - 1);
1836 real_convert (&minval, mode, &minval);
1837 real_arithmetic (&minval2, MINUS_EXPR, &minval, &dconst1);
1838 real_convert (&minval2, mode, &minval2);
1839 if (real_compare (EQ_EXPR, &minval, &minval2)
1840 && !real_isinf (&minval))
1842 /* If TYPE_MIN_VALUE - 1.0 is not representable and
1843 rounds to TYPE_MIN_VALUE, we need to subtract
1844 more. As REAL_MODE_FORMAT (mode)->p is the number
1845 of base digits, we want to subtract a number that
1846 will be 1 << (REAL_MODE_FORMAT (mode)->p - 1)
1847 times smaller than minval. */
1848 minval2 = dconst1;
1849 gcc_assert (prec > REAL_MODE_FORMAT (mode)->p);
1850 SET_REAL_EXP (&minval2,
1851 REAL_EXP (&minval2) + prec - 1
1852 - REAL_MODE_FORMAT (mode)->p + 1);
1853 real_arithmetic (&minval2, MINUS_EXPR, &minval, &minval2);
1854 real_convert (&minval2, mode, &minval2);
1856 min = build_real (expr_type, minval2);
1859 else if (REAL_MODE_FORMAT (mode)->b == 10)
1861 /* For _Decimal128 up to 34 decimal digits, - sign,
1862 dot, e, exponent. */
1863 char buf[64];
1864 mpfr_t m;
1865 int p = REAL_MODE_FORMAT (mode)->p;
1866 REAL_VALUE_TYPE maxval, minval;
1868 /* Use mpfr_snprintf rounding to compute the smallest
1869 representable decimal number greater or equal than
1870 1 << (prec - !uns_p). */
1871 mpfr_init2 (m, prec + 2);
1872 mpfr_set_ui_2exp (m, 1, prec - !uns_p, MPFR_RNDN);
1873 mpfr_snprintf (buf, sizeof buf, "%.*RUe", p - 1, m);
1874 decimal_real_from_string (&maxval, buf);
1875 max = build_real (expr_type, maxval);
1877 /* For unsigned, assume -1.0 is always representable. */
1878 if (uns_p)
1879 min = build_minus_one_cst (expr_type);
1880 else
1882 /* Use mpfr_snprintf rounding to compute the largest
1883 representable decimal number less or equal than
1884 (-1 << (prec - 1)) - 1. */
1885 mpfr_set_si_2exp (m, -1, prec - 1, MPFR_RNDN);
1886 mpfr_sub_ui (m, m, 1, MPFR_RNDN);
1887 mpfr_snprintf (buf, sizeof buf, "%.*RDe", p - 1, m);
1888 decimal_real_from_string (&minval, buf);
1889 min = build_real (expr_type, minval);
1891 mpfr_clear (m);
1893 else
1894 return NULL_TREE;
1896 if (HONOR_NANS (mode))
1898 t = fold_build2 (UNLE_EXPR, boolean_type_node, expr, min);
1899 tt = fold_build2 (UNGE_EXPR, boolean_type_node, expr, max);
1901 else
1903 t = fold_build2 (LE_EXPR, boolean_type_node, expr, min);
1904 tt = fold_build2 (GE_EXPR, boolean_type_node, expr, max);
1906 t = fold_build2 (TRUTH_OR_EXPR, boolean_type_node, t, tt);
1907 if (integer_zerop (t))
1908 return NULL_TREE;
1910 if (flag_sanitize_undefined_trap_on_error)
1911 fn = build_call_expr_loc (loc, builtin_decl_explicit (BUILT_IN_TRAP), 0);
1912 else
1914 location_t *loc_ptr = NULL;
1915 unsigned num_locations = 0;
1916 /* Figure out if we can propagate location to ubsan_data and use new
1917 style handlers in libubsan. */
1918 if (ubsan_use_new_style_p (loc))
1920 loc_ptr = &loc;
1921 num_locations = 1;
1923 /* Create the __ubsan_handle_float_cast_overflow fn call. */
1924 tree data = ubsan_create_data ("__ubsan_float_cast_overflow_data",
1925 num_locations, loc_ptr,
1926 ubsan_type_descriptor (expr_type),
1927 ubsan_type_descriptor (type), NULL_TREE,
1928 NULL_TREE);
1929 enum built_in_function bcode
1930 = (flag_sanitize_recover & SANITIZE_FLOAT_CAST)
1931 ? BUILT_IN_UBSAN_HANDLE_FLOAT_CAST_OVERFLOW
1932 : BUILT_IN_UBSAN_HANDLE_FLOAT_CAST_OVERFLOW_ABORT;
1933 fn = builtin_decl_explicit (bcode);
1934 fn = build_call_expr_loc (loc, fn, 2,
1935 build_fold_addr_expr_loc (loc, data),
1936 ubsan_encode_value (expr));
1939 return fold_build3 (COND_EXPR, void_type_node, t, fn, integer_zero_node);
1942 /* Instrument values passed to function arguments with nonnull attribute. */
1944 static void
1945 instrument_nonnull_arg (gimple_stmt_iterator *gsi)
1947 gimple *stmt = gsi_stmt (*gsi);
1948 location_t loc[2];
1949 /* infer_nonnull_range needs flag_delete_null_pointer_checks set,
1950 while for nonnull sanitization it is clear. */
1951 int save_flag_delete_null_pointer_checks = flag_delete_null_pointer_checks;
1952 flag_delete_null_pointer_checks = 1;
1953 loc[0] = gimple_location (stmt);
1954 loc[1] = UNKNOWN_LOCATION;
1955 for (unsigned int i = 0; i < gimple_call_num_args (stmt); i++)
1957 tree arg = gimple_call_arg (stmt, i);
1958 if (POINTER_TYPE_P (TREE_TYPE (arg))
1959 && infer_nonnull_range_by_attribute (stmt, arg))
1961 gimple *g;
1962 if (!is_gimple_val (arg))
1964 g = gimple_build_assign (make_ssa_name (TREE_TYPE (arg)), arg);
1965 gimple_set_location (g, loc[0]);
1966 gsi_insert_before (gsi, g, GSI_SAME_STMT);
1967 arg = gimple_assign_lhs (g);
1970 basic_block then_bb, fallthru_bb;
1971 *gsi = create_cond_insert_point (gsi, true, false, true,
1972 &then_bb, &fallthru_bb);
1973 g = gimple_build_cond (EQ_EXPR, arg,
1974 build_zero_cst (TREE_TYPE (arg)),
1975 NULL_TREE, NULL_TREE);
1976 gimple_set_location (g, loc[0]);
1977 gsi_insert_after (gsi, g, GSI_NEW_STMT);
1979 *gsi = gsi_after_labels (then_bb);
1980 if (flag_sanitize_undefined_trap_on_error)
1981 g = gimple_build_call (builtin_decl_explicit (BUILT_IN_TRAP), 0);
1982 else
1984 tree data = ubsan_create_data ("__ubsan_nonnull_arg_data",
1985 2, loc, NULL_TREE,
1986 build_int_cst (integer_type_node,
1987 i + 1),
1988 NULL_TREE);
1989 data = build_fold_addr_expr_loc (loc[0], data);
1990 enum built_in_function bcode
1991 = (flag_sanitize_recover & SANITIZE_NONNULL_ATTRIBUTE)
1992 ? BUILT_IN_UBSAN_HANDLE_NONNULL_ARG
1993 : BUILT_IN_UBSAN_HANDLE_NONNULL_ARG_ABORT;
1994 tree fn = builtin_decl_explicit (bcode);
1996 g = gimple_build_call (fn, 1, data);
1998 gimple_set_location (g, loc[0]);
1999 gsi_insert_before (gsi, g, GSI_SAME_STMT);
2000 ubsan_create_edge (g);
2002 *gsi = gsi_for_stmt (stmt);
2004 flag_delete_null_pointer_checks = save_flag_delete_null_pointer_checks;
2007 /* Instrument returns in functions with returns_nonnull attribute. */
2009 static void
2010 instrument_nonnull_return (gimple_stmt_iterator *gsi)
2012 greturn *stmt = as_a <greturn *> (gsi_stmt (*gsi));
2013 location_t loc[2];
2014 tree arg = gimple_return_retval (stmt);
2015 /* infer_nonnull_range needs flag_delete_null_pointer_checks set,
2016 while for nonnull return sanitization it is clear. */
2017 int save_flag_delete_null_pointer_checks = flag_delete_null_pointer_checks;
2018 flag_delete_null_pointer_checks = 1;
2019 loc[0] = gimple_location (stmt);
2020 loc[1] = UNKNOWN_LOCATION;
2021 if (arg
2022 && POINTER_TYPE_P (TREE_TYPE (arg))
2023 && is_gimple_val (arg)
2024 && infer_nonnull_range_by_attribute (stmt, arg))
2026 basic_block then_bb, fallthru_bb;
2027 *gsi = create_cond_insert_point (gsi, true, false, true,
2028 &then_bb, &fallthru_bb);
2029 gimple *g = gimple_build_cond (EQ_EXPR, arg,
2030 build_zero_cst (TREE_TYPE (arg)),
2031 NULL_TREE, NULL_TREE);
2032 gimple_set_location (g, loc[0]);
2033 gsi_insert_after (gsi, g, GSI_NEW_STMT);
2035 *gsi = gsi_after_labels (then_bb);
2036 if (flag_sanitize_undefined_trap_on_error)
2037 g = gimple_build_call (builtin_decl_explicit (BUILT_IN_TRAP), 0);
2038 else
2040 tree data = ubsan_create_data ("__ubsan_nonnull_return_data",
2041 1, &loc[1], NULL_TREE, NULL_TREE);
2042 data = build_fold_addr_expr_loc (loc[0], data);
2043 tree data2 = ubsan_create_data ("__ubsan_nonnull_return_data",
2044 1, &loc[0], NULL_TREE, NULL_TREE);
2045 data2 = build_fold_addr_expr_loc (loc[0], data2);
2046 enum built_in_function bcode
2047 = (flag_sanitize_recover & SANITIZE_RETURNS_NONNULL_ATTRIBUTE)
2048 ? BUILT_IN_UBSAN_HANDLE_NONNULL_RETURN_V1
2049 : BUILT_IN_UBSAN_HANDLE_NONNULL_RETURN_V1_ABORT;
2050 tree fn = builtin_decl_explicit (bcode);
2052 g = gimple_build_call (fn, 2, data, data2);
2054 gimple_set_location (g, loc[0]);
2055 gsi_insert_before (gsi, g, GSI_SAME_STMT);
2056 ubsan_create_edge (g);
2057 *gsi = gsi_for_stmt (stmt);
2059 flag_delete_null_pointer_checks = save_flag_delete_null_pointer_checks;
2062 /* Instrument memory references. Here we check whether the pointer
2063 points to an out-of-bounds location. */
2065 static void
2066 instrument_object_size (gimple_stmt_iterator *gsi, tree t, bool is_lhs)
2068 gimple *stmt = gsi_stmt (*gsi);
2069 location_t loc = gimple_location (stmt);
2070 tree type;
2071 tree index = NULL_TREE;
2072 HOST_WIDE_INT size_in_bytes;
2074 type = TREE_TYPE (t);
2075 if (VOID_TYPE_P (type))
2076 return;
2078 switch (TREE_CODE (t))
2080 case COMPONENT_REF:
2081 if (TREE_CODE (t) == COMPONENT_REF
2082 && DECL_BIT_FIELD_REPRESENTATIVE (TREE_OPERAND (t, 1)) != NULL_TREE)
2084 tree repr = DECL_BIT_FIELD_REPRESENTATIVE (TREE_OPERAND (t, 1));
2085 t = build3 (COMPONENT_REF, TREE_TYPE (repr), TREE_OPERAND (t, 0),
2086 repr, TREE_OPERAND (t, 2));
2088 break;
2089 case ARRAY_REF:
2090 index = TREE_OPERAND (t, 1);
2091 break;
2092 case INDIRECT_REF:
2093 case MEM_REF:
2094 case VAR_DECL:
2095 case PARM_DECL:
2096 case RESULT_DECL:
2097 break;
2098 default:
2099 return;
2102 size_in_bytes = int_size_in_bytes (type);
2103 if (size_in_bytes <= 0)
2104 return;
2106 poly_int64 bitsize, bitpos;
2107 tree offset;
2108 machine_mode mode;
2109 int volatilep = 0, reversep, unsignedp = 0;
2110 tree inner = get_inner_reference (t, &bitsize, &bitpos, &offset, &mode,
2111 &unsignedp, &reversep, &volatilep);
2113 if (!multiple_p (bitpos, BITS_PER_UNIT)
2114 || maybe_ne (bitsize, size_in_bytes * BITS_PER_UNIT))
2115 return;
2117 bool decl_p = DECL_P (inner);
2118 tree base;
2119 if (decl_p)
2121 if ((VAR_P (inner)
2122 || TREE_CODE (inner) == PARM_DECL
2123 || TREE_CODE (inner) == RESULT_DECL)
2124 && DECL_REGISTER (inner))
2125 return;
2126 base = inner;
2128 else if (TREE_CODE (inner) == MEM_REF)
2129 base = TREE_OPERAND (inner, 0);
2130 else
2131 return;
2132 tree ptr = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (t)), t);
2134 while (TREE_CODE (base) == SSA_NAME)
2136 gimple *def_stmt = SSA_NAME_DEF_STMT (base);
2137 if (gimple_assign_ssa_name_copy_p (def_stmt)
2138 || (gimple_assign_cast_p (def_stmt)
2139 && POINTER_TYPE_P (TREE_TYPE (gimple_assign_rhs1 (def_stmt))))
2140 || (is_gimple_assign (def_stmt)
2141 && gimple_assign_rhs_code (def_stmt) == POINTER_PLUS_EXPR))
2143 tree rhs1 = gimple_assign_rhs1 (def_stmt);
2144 if (TREE_CODE (rhs1) == SSA_NAME
2145 && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (rhs1))
2146 break;
2147 else
2148 base = rhs1;
2150 else
2151 break;
2154 if (!POINTER_TYPE_P (TREE_TYPE (base)) && !DECL_P (base))
2155 return;
2157 tree sizet;
2158 tree base_addr = base;
2159 gimple *bos_stmt = NULL;
2160 if (decl_p)
2161 base_addr = build1 (ADDR_EXPR,
2162 build_pointer_type (TREE_TYPE (base)), base);
2163 unsigned HOST_WIDE_INT size;
2164 if (compute_builtin_object_size (base_addr, 0, &size))
2165 sizet = build_int_cst (sizetype, size);
2166 else if (optimize)
2168 if (LOCATION_LOCUS (loc) == UNKNOWN_LOCATION)
2169 loc = input_location;
2170 /* Generate __builtin_object_size call. */
2171 sizet = builtin_decl_explicit (BUILT_IN_OBJECT_SIZE);
2172 sizet = build_call_expr_loc (loc, sizet, 2, base_addr,
2173 integer_zero_node);
2174 sizet = force_gimple_operand_gsi (gsi, sizet, false, NULL_TREE, true,
2175 GSI_SAME_STMT);
2176 /* If the call above didn't end up being an integer constant, go one
2177 statement back and get the __builtin_object_size stmt. Save it,
2178 we might need it later. */
2179 if (SSA_VAR_P (sizet))
2181 gsi_prev (gsi);
2182 bos_stmt = gsi_stmt (*gsi);
2184 /* Move on to where we were. */
2185 gsi_next (gsi);
2188 else
2189 return;
2191 /* Generate UBSAN_OBJECT_SIZE (ptr, ptr+sizeof(*ptr)-base, objsize, ckind)
2192 call. */
2193 /* ptr + sizeof (*ptr) - base */
2194 t = fold_build2 (MINUS_EXPR, sizetype,
2195 fold_convert (pointer_sized_int_node, ptr),
2196 fold_convert (pointer_sized_int_node, base_addr));
2197 t = fold_build2 (PLUS_EXPR, sizetype, t, TYPE_SIZE_UNIT (type));
2199 /* Perhaps we can omit the check. */
2200 if (TREE_CODE (t) == INTEGER_CST
2201 && TREE_CODE (sizet) == INTEGER_CST
2202 && tree_int_cst_le (t, sizet))
2203 return;
2205 if (index != NULL_TREE
2206 && TREE_CODE (index) == SSA_NAME
2207 && TREE_CODE (sizet) == INTEGER_CST)
2209 gimple *def = SSA_NAME_DEF_STMT (index);
2210 if (is_gimple_assign (def)
2211 && gimple_assign_rhs_code (def) == BIT_AND_EXPR
2212 && TREE_CODE (gimple_assign_rhs2 (def)) == INTEGER_CST)
2214 tree cst = gimple_assign_rhs2 (def);
2215 tree sz = fold_build2 (EXACT_DIV_EXPR, sizetype, sizet,
2216 TYPE_SIZE_UNIT (type));
2217 if (tree_int_cst_sgn (cst) >= 0
2218 && tree_int_cst_lt (cst, sz))
2219 return;
2223 if (bos_stmt && gimple_call_builtin_p (bos_stmt, BUILT_IN_OBJECT_SIZE))
2224 ubsan_create_edge (bos_stmt);
2226 /* We have to emit the check. */
2227 t = force_gimple_operand_gsi (gsi, t, true, NULL_TREE, true,
2228 GSI_SAME_STMT);
2229 ptr = force_gimple_operand_gsi (gsi, ptr, true, NULL_TREE, true,
2230 GSI_SAME_STMT);
2231 tree ckind = build_int_cst (unsigned_char_type_node,
2232 is_lhs ? UBSAN_STORE_OF : UBSAN_LOAD_OF);
2233 gimple *g = gimple_build_call_internal (IFN_UBSAN_OBJECT_SIZE, 4,
2234 ptr, t, sizet, ckind);
2235 gimple_set_location (g, loc);
2236 gsi_insert_before (gsi, g, GSI_SAME_STMT);
2239 /* Instrument values passed to builtin functions. */
2241 static void
2242 instrument_builtin (gimple_stmt_iterator *gsi)
2244 gimple *stmt = gsi_stmt (*gsi);
2245 location_t loc = gimple_location (stmt);
2246 tree arg;
2247 enum built_in_function fcode
2248 = DECL_FUNCTION_CODE (gimple_call_fndecl (stmt));
2249 int kind = 0;
2250 switch (fcode)
2252 CASE_INT_FN (BUILT_IN_CLZ):
2253 kind = 1;
2254 gcc_fallthrough ();
2255 CASE_INT_FN (BUILT_IN_CTZ):
2256 arg = gimple_call_arg (stmt, 0);
2257 if (!integer_nonzerop (arg))
2259 gimple *g;
2260 if (!is_gimple_val (arg))
2262 g = gimple_build_assign (make_ssa_name (TREE_TYPE (arg)), arg);
2263 gimple_set_location (g, loc);
2264 gsi_insert_before (gsi, g, GSI_SAME_STMT);
2265 arg = gimple_assign_lhs (g);
2268 basic_block then_bb, fallthru_bb;
2269 *gsi = create_cond_insert_point (gsi, true, false, true,
2270 &then_bb, &fallthru_bb);
2271 g = gimple_build_cond (EQ_EXPR, arg,
2272 build_zero_cst (TREE_TYPE (arg)),
2273 NULL_TREE, NULL_TREE);
2274 gimple_set_location (g, loc);
2275 gsi_insert_after (gsi, g, GSI_NEW_STMT);
2277 *gsi = gsi_after_labels (then_bb);
2278 if (flag_sanitize_undefined_trap_on_error)
2279 g = gimple_build_call (builtin_decl_explicit (BUILT_IN_TRAP), 0);
2280 else
2282 tree t = build_int_cst (unsigned_char_type_node, kind);
2283 tree data = ubsan_create_data ("__ubsan_builtin_data",
2284 1, &loc, NULL_TREE, t, NULL_TREE);
2285 data = build_fold_addr_expr_loc (loc, data);
2286 enum built_in_function bcode
2287 = (flag_sanitize_recover & SANITIZE_BUILTIN)
2288 ? BUILT_IN_UBSAN_HANDLE_INVALID_BUILTIN
2289 : BUILT_IN_UBSAN_HANDLE_INVALID_BUILTIN_ABORT;
2290 tree fn = builtin_decl_explicit (bcode);
2292 g = gimple_build_call (fn, 1, data);
2294 gimple_set_location (g, loc);
2295 gsi_insert_before (gsi, g, GSI_SAME_STMT);
2296 ubsan_create_edge (g);
2298 *gsi = gsi_for_stmt (stmt);
2299 break;
2300 default:
2301 break;
2305 namespace {
2307 const pass_data pass_data_ubsan =
2309 GIMPLE_PASS, /* type */
2310 "ubsan", /* name */
2311 OPTGROUP_NONE, /* optinfo_flags */
2312 TV_TREE_UBSAN, /* tv_id */
2313 ( PROP_cfg | PROP_ssa ), /* properties_required */
2314 0, /* properties_provided */
2315 0, /* properties_destroyed */
2316 0, /* todo_flags_start */
2317 TODO_update_ssa, /* todo_flags_finish */
2320 class pass_ubsan : public gimple_opt_pass
2322 public:
2323 pass_ubsan (gcc::context *ctxt)
2324 : gimple_opt_pass (pass_data_ubsan, ctxt)
2327 /* opt_pass methods: */
2328 virtual bool gate (function *)
2330 return sanitize_flags_p ((SANITIZE_NULL | SANITIZE_SI_OVERFLOW
2331 | SANITIZE_BOOL | SANITIZE_ENUM
2332 | SANITIZE_ALIGNMENT
2333 | SANITIZE_NONNULL_ATTRIBUTE
2334 | SANITIZE_RETURNS_NONNULL_ATTRIBUTE
2335 | SANITIZE_OBJECT_SIZE
2336 | SANITIZE_POINTER_OVERFLOW
2337 | SANITIZE_BUILTIN));
2340 virtual unsigned int execute (function *);
2342 }; // class pass_ubsan
2344 unsigned int
2345 pass_ubsan::execute (function *fun)
2347 basic_block bb;
2348 gimple_stmt_iterator gsi;
2349 unsigned int ret = 0;
2351 initialize_sanitizer_builtins ();
2353 FOR_EACH_BB_FN (bb, fun)
2355 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi);)
2357 gimple *stmt = gsi_stmt (gsi);
2358 if (is_gimple_debug (stmt) || gimple_clobber_p (stmt))
2360 gsi_next (&gsi);
2361 continue;
2364 if ((sanitize_flags_p (SANITIZE_SI_OVERFLOW, fun->decl))
2365 && is_gimple_assign (stmt))
2366 instrument_si_overflow (gsi);
2368 if (sanitize_flags_p (SANITIZE_NULL | SANITIZE_ALIGNMENT, fun->decl))
2370 if (gimple_store_p (stmt))
2371 instrument_null (gsi, gimple_get_lhs (stmt), true);
2372 if (gimple_assign_single_p (stmt))
2373 instrument_null (gsi, gimple_assign_rhs1 (stmt), false);
2374 if (is_gimple_call (stmt))
2376 unsigned args_num = gimple_call_num_args (stmt);
2377 for (unsigned i = 0; i < args_num; ++i)
2379 tree arg = gimple_call_arg (stmt, i);
2380 if (is_gimple_reg (arg) || is_gimple_min_invariant (arg))
2381 continue;
2382 instrument_null (gsi, arg, false);
2387 if (sanitize_flags_p (SANITIZE_BOOL | SANITIZE_ENUM, fun->decl)
2388 && gimple_assign_load_p (stmt))
2390 instrument_bool_enum_load (&gsi);
2391 bb = gimple_bb (stmt);
2394 if (sanitize_flags_p (SANITIZE_NONNULL_ATTRIBUTE, fun->decl)
2395 && is_gimple_call (stmt)
2396 && !gimple_call_internal_p (stmt))
2398 instrument_nonnull_arg (&gsi);
2399 bb = gimple_bb (stmt);
2402 if (sanitize_flags_p (SANITIZE_BUILTIN, fun->decl)
2403 && gimple_call_builtin_p (stmt, BUILT_IN_NORMAL))
2405 instrument_builtin (&gsi);
2406 bb = gimple_bb (stmt);
2409 if (sanitize_flags_p (SANITIZE_RETURNS_NONNULL_ATTRIBUTE, fun->decl)
2410 && gimple_code (stmt) == GIMPLE_RETURN)
2412 instrument_nonnull_return (&gsi);
2413 bb = gimple_bb (stmt);
2416 if (sanitize_flags_p (SANITIZE_OBJECT_SIZE, fun->decl))
2418 if (gimple_store_p (stmt))
2419 instrument_object_size (&gsi, gimple_get_lhs (stmt), true);
2420 if (gimple_assign_load_p (stmt))
2421 instrument_object_size (&gsi, gimple_assign_rhs1 (stmt),
2422 false);
2423 if (is_gimple_call (stmt))
2425 unsigned args_num = gimple_call_num_args (stmt);
2426 for (unsigned i = 0; i < args_num; ++i)
2428 tree arg = gimple_call_arg (stmt, i);
2429 if (is_gimple_reg (arg) || is_gimple_min_invariant (arg))
2430 continue;
2431 instrument_object_size (&gsi, arg, false);
2436 if (sanitize_flags_p (SANITIZE_POINTER_OVERFLOW, fun->decl))
2438 if (is_gimple_assign (stmt)
2439 && gimple_assign_rhs_code (stmt) == POINTER_PLUS_EXPR)
2440 instrument_pointer_overflow (&gsi,
2441 gimple_assign_rhs1 (stmt),
2442 gimple_assign_rhs2 (stmt));
2443 if (gimple_store_p (stmt))
2444 maybe_instrument_pointer_overflow (&gsi,
2445 gimple_get_lhs (stmt));
2446 if (gimple_assign_single_p (stmt))
2447 maybe_instrument_pointer_overflow (&gsi,
2448 gimple_assign_rhs1 (stmt));
2449 if (is_gimple_call (stmt))
2451 unsigned args_num = gimple_call_num_args (stmt);
2452 for (unsigned i = 0; i < args_num; ++i)
2454 tree arg = gimple_call_arg (stmt, i);
2455 if (is_gimple_reg (arg))
2456 continue;
2457 maybe_instrument_pointer_overflow (&gsi, arg);
2462 gsi_next (&gsi);
2464 if (gimple_purge_dead_eh_edges (bb))
2465 ret = TODO_cleanup_cfg;
2467 return ret;
2470 } // anon namespace
2472 gimple_opt_pass *
2473 make_pass_ubsan (gcc::context *ctxt)
2475 return new pass_ubsan (ctxt);
2478 #include "gt-ubsan.h"