* tsan.c (instrument_expr): corrected previous checkin.
[official-gcc.git] / gcc / tsan.c
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1 /* GCC instrumentation plugin for ThreadSanitizer.
2 Copyright (C) 2011-2014 Free Software Foundation, Inc.
3 Contributed by Dmitry Vyukov <dvyukov@google.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/>. */
22 #include "config.h"
23 #include "system.h"
24 #include "coretypes.h"
25 #include "tree.h"
26 #include "expr.h"
27 #include "intl.h"
28 #include "tm.h"
29 #include "predict.h"
30 #include "vec.h"
31 #include "hashtab.h"
32 #include "hash-set.h"
33 #include "machmode.h"
34 #include "hard-reg-set.h"
35 #include "input.h"
36 #include "function.h"
37 #include "dominance.h"
38 #include "cfg.h"
39 #include "basic-block.h"
40 #include "tree-ssa-alias.h"
41 #include "internal-fn.h"
42 #include "gimple-expr.h"
43 #include "is-a.h"
44 #include "gimple.h"
45 #include "gimplify.h"
46 #include "gimple-iterator.h"
47 #include "gimple-ssa.h"
48 #include "hash-map.h"
49 #include "plugin-api.h"
50 #include "ipa-ref.h"
51 #include "cgraph.h"
52 #include "tree-cfg.h"
53 #include "stringpool.h"
54 #include "tree-ssanames.h"
55 #include "tree-pass.h"
56 #include "tree-iterator.h"
57 #include "langhooks.h"
58 #include "output.h"
59 #include "options.h"
60 #include "target.h"
61 #include "diagnostic.h"
62 #include "tree-ssa-propagate.h"
63 #include "tsan.h"
64 #include "asan.h"
65 #include "builtins.h"
67 /* Number of instrumented memory accesses in the current function. */
69 /* Builds the following decl
70 void __tsan_read/writeX (void *addr); */
72 static tree
73 get_memory_access_decl (bool is_write, unsigned size)
75 enum built_in_function fcode;
77 if (size <= 1)
78 fcode = is_write ? BUILT_IN_TSAN_WRITE1
79 : BUILT_IN_TSAN_READ1;
80 else if (size <= 3)
81 fcode = is_write ? BUILT_IN_TSAN_WRITE2
82 : BUILT_IN_TSAN_READ2;
83 else if (size <= 7)
84 fcode = is_write ? BUILT_IN_TSAN_WRITE4
85 : BUILT_IN_TSAN_READ4;
86 else if (size <= 15)
87 fcode = is_write ? BUILT_IN_TSAN_WRITE8
88 : BUILT_IN_TSAN_READ8;
89 else
90 fcode = is_write ? BUILT_IN_TSAN_WRITE16
91 : BUILT_IN_TSAN_READ16;
93 return builtin_decl_implicit (fcode);
96 /* Check as to whether EXPR refers to a store to vptr. */
98 static tree
99 is_vptr_store (gimple stmt, tree expr, bool is_write)
101 if (is_write == true
102 && gimple_assign_single_p (stmt)
103 && TREE_CODE (expr) == COMPONENT_REF)
105 tree field = TREE_OPERAND (expr, 1);
106 if (TREE_CODE (field) == FIELD_DECL
107 && DECL_VIRTUAL_P (field))
108 return gimple_assign_rhs1 (stmt);
110 return NULL;
113 /* Instruments EXPR if needed. If any instrumentation is inserted,
114 return true. */
116 static bool
117 instrument_expr (gimple_stmt_iterator gsi, tree expr, bool is_write)
119 tree base, rhs, expr_ptr, builtin_decl;
120 basic_block bb;
121 HOST_WIDE_INT size;
122 gimple stmt, g;
123 gimple_seq seq;
124 location_t loc;
125 unsigned int align;
127 size = int_size_in_bytes (TREE_TYPE (expr));
128 if (size <= 0)
129 return false;
131 HOST_WIDE_INT bitsize, bitpos;
132 tree offset;
133 machine_mode mode;
134 int volatilep = 0, unsignedp = 0;
135 base = get_inner_reference (expr, &bitsize, &bitpos, &offset,
136 &mode, &unsignedp, &volatilep, false);
138 /* No need to instrument accesses to decls that don't escape,
139 they can't escape to other threads then. */
140 if (DECL_P (base))
142 struct pt_solution pt;
143 memset (&pt, 0, sizeof (pt));
144 pt.escaped = 1;
145 pt.ipa_escaped = flag_ipa_pta != 0;
146 pt.nonlocal = 1;
147 if (!pt_solution_includes (&pt, base))
148 return false;
149 if (!is_global_var (base) && !may_be_aliased (base))
150 return false;
153 if (TREE_READONLY (base)
154 || (TREE_CODE (base) == VAR_DECL
155 && DECL_HARD_REGISTER (base)))
156 return false;
158 stmt = gsi_stmt (gsi);
159 loc = gimple_location (stmt);
160 rhs = is_vptr_store (stmt, expr, is_write);
161 seq = NULL;
163 if ((TREE_CODE (expr) == COMPONENT_REF
164 && DECL_BIT_FIELD_TYPE (TREE_OPERAND (expr, 1)))
165 || TREE_CODE (expr) == BIT_FIELD_REF)
167 base = TREE_OPERAND (expr, 0);
168 if (TREE_CODE (expr) == COMPONENT_REF)
170 expr = TREE_OPERAND (expr, 1);
171 if (is_write && DECL_BIT_FIELD_REPRESENTATIVE (expr))
172 expr = DECL_BIT_FIELD_REPRESENTATIVE (expr);
173 if (!tree_fits_uhwi_p (DECL_FIELD_OFFSET (expr))
174 || !tree_fits_uhwi_p (DECL_FIELD_BIT_OFFSET (expr))
175 || !tree_fits_uhwi_p (DECL_SIZE (expr)))
176 return false;
177 bitpos = tree_to_uhwi (DECL_FIELD_OFFSET (expr)) * BITS_PER_UNIT
178 + tree_to_uhwi (DECL_FIELD_BIT_OFFSET (expr));
179 bitsize = tree_to_uhwi (DECL_SIZE (expr));
181 else
183 if (!tree_fits_uhwi_p (TREE_OPERAND (expr, 2))
184 || !tree_fits_uhwi_p (TREE_OPERAND (expr, 1)))
185 return false;
186 bitpos = tree_to_uhwi (TREE_OPERAND (expr, 2));
187 bitsize = tree_to_uhwi (TREE_OPERAND (expr, 1));
189 if (bitpos < 0 || bitsize <= 0)
190 return false;
191 size = (bitpos % BITS_PER_UNIT + bitsize + BITS_PER_UNIT - 1)
192 / BITS_PER_UNIT;
193 align = get_object_alignment (base);
194 if (align < BITS_PER_UNIT)
195 return false;
196 bitpos = bitpos & ~(BITS_PER_UNIT - 1);
197 if ((align - 1) & bitpos)
199 align = (align - 1) & bitpos;
200 align = align & -align;
202 gcc_checking_assert (is_gimple_addressable (base));
203 expr = build_fold_addr_expr (unshare_expr (base));
204 if (!is_gimple_mem_ref_addr (expr))
206 g = gimple_build_assign (make_ssa_name (TREE_TYPE (expr)), expr);
207 expr = gimple_assign_lhs (g);
208 gimple_set_location (g, loc);
209 gimple_seq_add_stmt_without_update (&seq, g);
211 expr = build2 (MEM_REF, char_type_node, expr,
212 build_int_cst (TREE_TYPE (expr), bitpos / BITS_PER_UNIT));
213 expr_ptr = build_fold_addr_expr (expr);
215 else
217 align = get_object_alignment (expr);
218 if (align < BITS_PER_UNIT)
219 return false;
220 gcc_checking_assert (is_gimple_addressable (expr));
221 expr_ptr = build_fold_addr_expr (unshare_expr (expr));
223 if (!is_gimple_val (expr_ptr))
225 g = gimple_build_assign (make_ssa_name (TREE_TYPE (expr_ptr)), expr_ptr);
226 expr_ptr = gimple_assign_lhs (g);
227 gimple_set_location (g, loc);
228 gimple_seq_add_stmt_without_update (&seq, g);
230 if ((size & (size - 1)) != 0 || size > 16
231 || align < MIN (size, 8) * BITS_PER_UNIT)
233 builtin_decl = builtin_decl_implicit (is_write
234 ? BUILT_IN_TSAN_WRITE_RANGE
235 : BUILT_IN_TSAN_READ_RANGE);
236 g = gimple_build_call (builtin_decl, 2, expr_ptr, size_int (size));
238 else if (rhs == NULL)
239 g = gimple_build_call (get_memory_access_decl (is_write, size),
240 1, expr_ptr);
241 else
243 builtin_decl = builtin_decl_implicit (BUILT_IN_TSAN_VPTR_UPDATE);
244 g = gimple_build_call (builtin_decl, 1, expr_ptr);
246 gimple_set_location (g, loc);
247 gimple_seq_add_stmt_without_update (&seq, g);
248 /* Instrumentation for assignment of a function result
249 must be inserted after the call. Instrumentation for
250 reads of function arguments must be inserted before the call.
251 That's because the call can contain synchronization. */
252 if (is_gimple_call (stmt) && is_write)
254 /* If the call can throw, it must be the last stmt in
255 a basic block, so the instrumented stmts need to be
256 inserted in successor bbs. */
257 if (is_ctrl_altering_stmt (stmt))
259 edge e;
261 bb = gsi_bb (gsi);
262 e = find_fallthru_edge (bb->succs);
263 if (e)
264 gsi_insert_seq_on_edge_immediate (e, seq);
266 else
267 gsi_insert_seq_after (&gsi, seq, GSI_NEW_STMT);
269 else
270 gsi_insert_seq_before (&gsi, seq, GSI_SAME_STMT);
272 return true;
275 /* Actions for sync/atomic builtin transformations. */
276 enum tsan_atomic_action
278 check_last, add_seq_cst, add_acquire, weak_cas, strong_cas,
279 bool_cas, val_cas, lock_release, fetch_op, fetch_op_seq_cst
282 /* Table how to map sync/atomic builtins to their corresponding
283 tsan equivalents. */
284 static const struct tsan_map_atomic
286 enum built_in_function fcode, tsan_fcode;
287 enum tsan_atomic_action action;
288 enum tree_code code;
289 } tsan_atomic_table[] =
291 #define TRANSFORM(fcode, tsan_fcode, action, code) \
292 { BUILT_IN_##fcode, BUILT_IN_##tsan_fcode, action, code }
293 #define CHECK_LAST(fcode, tsan_fcode) \
294 TRANSFORM (fcode, tsan_fcode, check_last, ERROR_MARK)
295 #define ADD_SEQ_CST(fcode, tsan_fcode) \
296 TRANSFORM (fcode, tsan_fcode, add_seq_cst, ERROR_MARK)
297 #define ADD_ACQUIRE(fcode, tsan_fcode) \
298 TRANSFORM (fcode, tsan_fcode, add_acquire, ERROR_MARK)
299 #define WEAK_CAS(fcode, tsan_fcode) \
300 TRANSFORM (fcode, tsan_fcode, weak_cas, ERROR_MARK)
301 #define STRONG_CAS(fcode, tsan_fcode) \
302 TRANSFORM (fcode, tsan_fcode, strong_cas, ERROR_MARK)
303 #define BOOL_CAS(fcode, tsan_fcode) \
304 TRANSFORM (fcode, tsan_fcode, bool_cas, ERROR_MARK)
305 #define VAL_CAS(fcode, tsan_fcode) \
306 TRANSFORM (fcode, tsan_fcode, val_cas, ERROR_MARK)
307 #define LOCK_RELEASE(fcode, tsan_fcode) \
308 TRANSFORM (fcode, tsan_fcode, lock_release, ERROR_MARK)
309 #define FETCH_OP(fcode, tsan_fcode, code) \
310 TRANSFORM (fcode, tsan_fcode, fetch_op, code)
311 #define FETCH_OPS(fcode, tsan_fcode, code) \
312 TRANSFORM (fcode, tsan_fcode, fetch_op_seq_cst, code)
314 CHECK_LAST (ATOMIC_LOAD_1, TSAN_ATOMIC8_LOAD),
315 CHECK_LAST (ATOMIC_LOAD_2, TSAN_ATOMIC16_LOAD),
316 CHECK_LAST (ATOMIC_LOAD_4, TSAN_ATOMIC32_LOAD),
317 CHECK_LAST (ATOMIC_LOAD_8, TSAN_ATOMIC64_LOAD),
318 CHECK_LAST (ATOMIC_LOAD_16, TSAN_ATOMIC128_LOAD),
319 CHECK_LAST (ATOMIC_STORE_1, TSAN_ATOMIC8_STORE),
320 CHECK_LAST (ATOMIC_STORE_2, TSAN_ATOMIC16_STORE),
321 CHECK_LAST (ATOMIC_STORE_4, TSAN_ATOMIC32_STORE),
322 CHECK_LAST (ATOMIC_STORE_8, TSAN_ATOMIC64_STORE),
323 CHECK_LAST (ATOMIC_STORE_16, TSAN_ATOMIC128_STORE),
324 CHECK_LAST (ATOMIC_EXCHANGE_1, TSAN_ATOMIC8_EXCHANGE),
325 CHECK_LAST (ATOMIC_EXCHANGE_2, TSAN_ATOMIC16_EXCHANGE),
326 CHECK_LAST (ATOMIC_EXCHANGE_4, TSAN_ATOMIC32_EXCHANGE),
327 CHECK_LAST (ATOMIC_EXCHANGE_8, TSAN_ATOMIC64_EXCHANGE),
328 CHECK_LAST (ATOMIC_EXCHANGE_16, TSAN_ATOMIC128_EXCHANGE),
329 CHECK_LAST (ATOMIC_FETCH_ADD_1, TSAN_ATOMIC8_FETCH_ADD),
330 CHECK_LAST (ATOMIC_FETCH_ADD_2, TSAN_ATOMIC16_FETCH_ADD),
331 CHECK_LAST (ATOMIC_FETCH_ADD_4, TSAN_ATOMIC32_FETCH_ADD),
332 CHECK_LAST (ATOMIC_FETCH_ADD_8, TSAN_ATOMIC64_FETCH_ADD),
333 CHECK_LAST (ATOMIC_FETCH_ADD_16, TSAN_ATOMIC128_FETCH_ADD),
334 CHECK_LAST (ATOMIC_FETCH_SUB_1, TSAN_ATOMIC8_FETCH_SUB),
335 CHECK_LAST (ATOMIC_FETCH_SUB_2, TSAN_ATOMIC16_FETCH_SUB),
336 CHECK_LAST (ATOMIC_FETCH_SUB_4, TSAN_ATOMIC32_FETCH_SUB),
337 CHECK_LAST (ATOMIC_FETCH_SUB_8, TSAN_ATOMIC64_FETCH_SUB),
338 CHECK_LAST (ATOMIC_FETCH_SUB_16, TSAN_ATOMIC128_FETCH_SUB),
339 CHECK_LAST (ATOMIC_FETCH_AND_1, TSAN_ATOMIC8_FETCH_AND),
340 CHECK_LAST (ATOMIC_FETCH_AND_2, TSAN_ATOMIC16_FETCH_AND),
341 CHECK_LAST (ATOMIC_FETCH_AND_4, TSAN_ATOMIC32_FETCH_AND),
342 CHECK_LAST (ATOMIC_FETCH_AND_8, TSAN_ATOMIC64_FETCH_AND),
343 CHECK_LAST (ATOMIC_FETCH_AND_16, TSAN_ATOMIC128_FETCH_AND),
344 CHECK_LAST (ATOMIC_FETCH_OR_1, TSAN_ATOMIC8_FETCH_OR),
345 CHECK_LAST (ATOMIC_FETCH_OR_2, TSAN_ATOMIC16_FETCH_OR),
346 CHECK_LAST (ATOMIC_FETCH_OR_4, TSAN_ATOMIC32_FETCH_OR),
347 CHECK_LAST (ATOMIC_FETCH_OR_8, TSAN_ATOMIC64_FETCH_OR),
348 CHECK_LAST (ATOMIC_FETCH_OR_16, TSAN_ATOMIC128_FETCH_OR),
349 CHECK_LAST (ATOMIC_FETCH_XOR_1, TSAN_ATOMIC8_FETCH_XOR),
350 CHECK_LAST (ATOMIC_FETCH_XOR_2, TSAN_ATOMIC16_FETCH_XOR),
351 CHECK_LAST (ATOMIC_FETCH_XOR_4, TSAN_ATOMIC32_FETCH_XOR),
352 CHECK_LAST (ATOMIC_FETCH_XOR_8, TSAN_ATOMIC64_FETCH_XOR),
353 CHECK_LAST (ATOMIC_FETCH_XOR_16, TSAN_ATOMIC128_FETCH_XOR),
354 CHECK_LAST (ATOMIC_FETCH_NAND_1, TSAN_ATOMIC8_FETCH_NAND),
355 CHECK_LAST (ATOMIC_FETCH_NAND_2, TSAN_ATOMIC16_FETCH_NAND),
356 CHECK_LAST (ATOMIC_FETCH_NAND_4, TSAN_ATOMIC32_FETCH_NAND),
357 CHECK_LAST (ATOMIC_FETCH_NAND_8, TSAN_ATOMIC64_FETCH_NAND),
358 CHECK_LAST (ATOMIC_FETCH_NAND_16, TSAN_ATOMIC128_FETCH_NAND),
360 CHECK_LAST (ATOMIC_THREAD_FENCE, TSAN_ATOMIC_THREAD_FENCE),
361 CHECK_LAST (ATOMIC_SIGNAL_FENCE, TSAN_ATOMIC_SIGNAL_FENCE),
363 FETCH_OP (ATOMIC_ADD_FETCH_1, TSAN_ATOMIC8_FETCH_ADD, PLUS_EXPR),
364 FETCH_OP (ATOMIC_ADD_FETCH_2, TSAN_ATOMIC16_FETCH_ADD, PLUS_EXPR),
365 FETCH_OP (ATOMIC_ADD_FETCH_4, TSAN_ATOMIC32_FETCH_ADD, PLUS_EXPR),
366 FETCH_OP (ATOMIC_ADD_FETCH_8, TSAN_ATOMIC64_FETCH_ADD, PLUS_EXPR),
367 FETCH_OP (ATOMIC_ADD_FETCH_16, TSAN_ATOMIC128_FETCH_ADD, PLUS_EXPR),
368 FETCH_OP (ATOMIC_SUB_FETCH_1, TSAN_ATOMIC8_FETCH_SUB, MINUS_EXPR),
369 FETCH_OP (ATOMIC_SUB_FETCH_2, TSAN_ATOMIC16_FETCH_SUB, MINUS_EXPR),
370 FETCH_OP (ATOMIC_SUB_FETCH_4, TSAN_ATOMIC32_FETCH_SUB, MINUS_EXPR),
371 FETCH_OP (ATOMIC_SUB_FETCH_8, TSAN_ATOMIC64_FETCH_SUB, MINUS_EXPR),
372 FETCH_OP (ATOMIC_SUB_FETCH_16, TSAN_ATOMIC128_FETCH_SUB, MINUS_EXPR),
373 FETCH_OP (ATOMIC_AND_FETCH_1, TSAN_ATOMIC8_FETCH_AND, BIT_AND_EXPR),
374 FETCH_OP (ATOMIC_AND_FETCH_2, TSAN_ATOMIC16_FETCH_AND, BIT_AND_EXPR),
375 FETCH_OP (ATOMIC_AND_FETCH_4, TSAN_ATOMIC32_FETCH_AND, BIT_AND_EXPR),
376 FETCH_OP (ATOMIC_AND_FETCH_8, TSAN_ATOMIC64_FETCH_AND, BIT_AND_EXPR),
377 FETCH_OP (ATOMIC_AND_FETCH_16, TSAN_ATOMIC128_FETCH_AND, BIT_AND_EXPR),
378 FETCH_OP (ATOMIC_OR_FETCH_1, TSAN_ATOMIC8_FETCH_OR, BIT_IOR_EXPR),
379 FETCH_OP (ATOMIC_OR_FETCH_2, TSAN_ATOMIC16_FETCH_OR, BIT_IOR_EXPR),
380 FETCH_OP (ATOMIC_OR_FETCH_4, TSAN_ATOMIC32_FETCH_OR, BIT_IOR_EXPR),
381 FETCH_OP (ATOMIC_OR_FETCH_8, TSAN_ATOMIC64_FETCH_OR, BIT_IOR_EXPR),
382 FETCH_OP (ATOMIC_OR_FETCH_16, TSAN_ATOMIC128_FETCH_OR, BIT_IOR_EXPR),
383 FETCH_OP (ATOMIC_XOR_FETCH_1, TSAN_ATOMIC8_FETCH_XOR, BIT_XOR_EXPR),
384 FETCH_OP (ATOMIC_XOR_FETCH_2, TSAN_ATOMIC16_FETCH_XOR, BIT_XOR_EXPR),
385 FETCH_OP (ATOMIC_XOR_FETCH_4, TSAN_ATOMIC32_FETCH_XOR, BIT_XOR_EXPR),
386 FETCH_OP (ATOMIC_XOR_FETCH_8, TSAN_ATOMIC64_FETCH_XOR, BIT_XOR_EXPR),
387 FETCH_OP (ATOMIC_XOR_FETCH_16, TSAN_ATOMIC128_FETCH_XOR, BIT_XOR_EXPR),
388 FETCH_OP (ATOMIC_NAND_FETCH_1, TSAN_ATOMIC8_FETCH_NAND, BIT_NOT_EXPR),
389 FETCH_OP (ATOMIC_NAND_FETCH_2, TSAN_ATOMIC16_FETCH_NAND, BIT_NOT_EXPR),
390 FETCH_OP (ATOMIC_NAND_FETCH_4, TSAN_ATOMIC32_FETCH_NAND, BIT_NOT_EXPR),
391 FETCH_OP (ATOMIC_NAND_FETCH_8, TSAN_ATOMIC64_FETCH_NAND, BIT_NOT_EXPR),
392 FETCH_OP (ATOMIC_NAND_FETCH_16, TSAN_ATOMIC128_FETCH_NAND, BIT_NOT_EXPR),
394 ADD_ACQUIRE (SYNC_LOCK_TEST_AND_SET_1, TSAN_ATOMIC8_EXCHANGE),
395 ADD_ACQUIRE (SYNC_LOCK_TEST_AND_SET_2, TSAN_ATOMIC16_EXCHANGE),
396 ADD_ACQUIRE (SYNC_LOCK_TEST_AND_SET_4, TSAN_ATOMIC32_EXCHANGE),
397 ADD_ACQUIRE (SYNC_LOCK_TEST_AND_SET_8, TSAN_ATOMIC64_EXCHANGE),
398 ADD_ACQUIRE (SYNC_LOCK_TEST_AND_SET_16, TSAN_ATOMIC128_EXCHANGE),
400 ADD_SEQ_CST (SYNC_FETCH_AND_ADD_1, TSAN_ATOMIC8_FETCH_ADD),
401 ADD_SEQ_CST (SYNC_FETCH_AND_ADD_2, TSAN_ATOMIC16_FETCH_ADD),
402 ADD_SEQ_CST (SYNC_FETCH_AND_ADD_4, TSAN_ATOMIC32_FETCH_ADD),
403 ADD_SEQ_CST (SYNC_FETCH_AND_ADD_8, TSAN_ATOMIC64_FETCH_ADD),
404 ADD_SEQ_CST (SYNC_FETCH_AND_ADD_16, TSAN_ATOMIC128_FETCH_ADD),
405 ADD_SEQ_CST (SYNC_FETCH_AND_SUB_1, TSAN_ATOMIC8_FETCH_SUB),
406 ADD_SEQ_CST (SYNC_FETCH_AND_SUB_2, TSAN_ATOMIC16_FETCH_SUB),
407 ADD_SEQ_CST (SYNC_FETCH_AND_SUB_4, TSAN_ATOMIC32_FETCH_SUB),
408 ADD_SEQ_CST (SYNC_FETCH_AND_SUB_8, TSAN_ATOMIC64_FETCH_SUB),
409 ADD_SEQ_CST (SYNC_FETCH_AND_SUB_16, TSAN_ATOMIC128_FETCH_SUB),
410 ADD_SEQ_CST (SYNC_FETCH_AND_AND_1, TSAN_ATOMIC8_FETCH_AND),
411 ADD_SEQ_CST (SYNC_FETCH_AND_AND_2, TSAN_ATOMIC16_FETCH_AND),
412 ADD_SEQ_CST (SYNC_FETCH_AND_AND_4, TSAN_ATOMIC32_FETCH_AND),
413 ADD_SEQ_CST (SYNC_FETCH_AND_AND_8, TSAN_ATOMIC64_FETCH_AND),
414 ADD_SEQ_CST (SYNC_FETCH_AND_AND_16, TSAN_ATOMIC128_FETCH_AND),
415 ADD_SEQ_CST (SYNC_FETCH_AND_OR_1, TSAN_ATOMIC8_FETCH_OR),
416 ADD_SEQ_CST (SYNC_FETCH_AND_OR_2, TSAN_ATOMIC16_FETCH_OR),
417 ADD_SEQ_CST (SYNC_FETCH_AND_OR_4, TSAN_ATOMIC32_FETCH_OR),
418 ADD_SEQ_CST (SYNC_FETCH_AND_OR_8, TSAN_ATOMIC64_FETCH_OR),
419 ADD_SEQ_CST (SYNC_FETCH_AND_OR_16, TSAN_ATOMIC128_FETCH_OR),
420 ADD_SEQ_CST (SYNC_FETCH_AND_XOR_1, TSAN_ATOMIC8_FETCH_XOR),
421 ADD_SEQ_CST (SYNC_FETCH_AND_XOR_2, TSAN_ATOMIC16_FETCH_XOR),
422 ADD_SEQ_CST (SYNC_FETCH_AND_XOR_4, TSAN_ATOMIC32_FETCH_XOR),
423 ADD_SEQ_CST (SYNC_FETCH_AND_XOR_8, TSAN_ATOMIC64_FETCH_XOR),
424 ADD_SEQ_CST (SYNC_FETCH_AND_XOR_16, TSAN_ATOMIC128_FETCH_XOR),
425 ADD_SEQ_CST (SYNC_FETCH_AND_NAND_1, TSAN_ATOMIC8_FETCH_NAND),
426 ADD_SEQ_CST (SYNC_FETCH_AND_NAND_2, TSAN_ATOMIC16_FETCH_NAND),
427 ADD_SEQ_CST (SYNC_FETCH_AND_NAND_4, TSAN_ATOMIC32_FETCH_NAND),
428 ADD_SEQ_CST (SYNC_FETCH_AND_NAND_8, TSAN_ATOMIC64_FETCH_NAND),
429 ADD_SEQ_CST (SYNC_FETCH_AND_NAND_16, TSAN_ATOMIC128_FETCH_NAND),
431 ADD_SEQ_CST (SYNC_SYNCHRONIZE, TSAN_ATOMIC_THREAD_FENCE),
433 FETCH_OPS (SYNC_ADD_AND_FETCH_1, TSAN_ATOMIC8_FETCH_ADD, PLUS_EXPR),
434 FETCH_OPS (SYNC_ADD_AND_FETCH_2, TSAN_ATOMIC16_FETCH_ADD, PLUS_EXPR),
435 FETCH_OPS (SYNC_ADD_AND_FETCH_4, TSAN_ATOMIC32_FETCH_ADD, PLUS_EXPR),
436 FETCH_OPS (SYNC_ADD_AND_FETCH_8, TSAN_ATOMIC64_FETCH_ADD, PLUS_EXPR),
437 FETCH_OPS (SYNC_ADD_AND_FETCH_16, TSAN_ATOMIC128_FETCH_ADD, PLUS_EXPR),
438 FETCH_OPS (SYNC_SUB_AND_FETCH_1, TSAN_ATOMIC8_FETCH_SUB, MINUS_EXPR),
439 FETCH_OPS (SYNC_SUB_AND_FETCH_2, TSAN_ATOMIC16_FETCH_SUB, MINUS_EXPR),
440 FETCH_OPS (SYNC_SUB_AND_FETCH_4, TSAN_ATOMIC32_FETCH_SUB, MINUS_EXPR),
441 FETCH_OPS (SYNC_SUB_AND_FETCH_8, TSAN_ATOMIC64_FETCH_SUB, MINUS_EXPR),
442 FETCH_OPS (SYNC_SUB_AND_FETCH_16, TSAN_ATOMIC128_FETCH_SUB, MINUS_EXPR),
443 FETCH_OPS (SYNC_AND_AND_FETCH_1, TSAN_ATOMIC8_FETCH_AND, BIT_AND_EXPR),
444 FETCH_OPS (SYNC_AND_AND_FETCH_2, TSAN_ATOMIC16_FETCH_AND, BIT_AND_EXPR),
445 FETCH_OPS (SYNC_AND_AND_FETCH_4, TSAN_ATOMIC32_FETCH_AND, BIT_AND_EXPR),
446 FETCH_OPS (SYNC_AND_AND_FETCH_8, TSAN_ATOMIC64_FETCH_AND, BIT_AND_EXPR),
447 FETCH_OPS (SYNC_AND_AND_FETCH_16, TSAN_ATOMIC128_FETCH_AND, BIT_AND_EXPR),
448 FETCH_OPS (SYNC_OR_AND_FETCH_1, TSAN_ATOMIC8_FETCH_OR, BIT_IOR_EXPR),
449 FETCH_OPS (SYNC_OR_AND_FETCH_2, TSAN_ATOMIC16_FETCH_OR, BIT_IOR_EXPR),
450 FETCH_OPS (SYNC_OR_AND_FETCH_4, TSAN_ATOMIC32_FETCH_OR, BIT_IOR_EXPR),
451 FETCH_OPS (SYNC_OR_AND_FETCH_8, TSAN_ATOMIC64_FETCH_OR, BIT_IOR_EXPR),
452 FETCH_OPS (SYNC_OR_AND_FETCH_16, TSAN_ATOMIC128_FETCH_OR, BIT_IOR_EXPR),
453 FETCH_OPS (SYNC_XOR_AND_FETCH_1, TSAN_ATOMIC8_FETCH_XOR, BIT_XOR_EXPR),
454 FETCH_OPS (SYNC_XOR_AND_FETCH_2, TSAN_ATOMIC16_FETCH_XOR, BIT_XOR_EXPR),
455 FETCH_OPS (SYNC_XOR_AND_FETCH_4, TSAN_ATOMIC32_FETCH_XOR, BIT_XOR_EXPR),
456 FETCH_OPS (SYNC_XOR_AND_FETCH_8, TSAN_ATOMIC64_FETCH_XOR, BIT_XOR_EXPR),
457 FETCH_OPS (SYNC_XOR_AND_FETCH_16, TSAN_ATOMIC128_FETCH_XOR, BIT_XOR_EXPR),
458 FETCH_OPS (SYNC_NAND_AND_FETCH_1, TSAN_ATOMIC8_FETCH_NAND, BIT_NOT_EXPR),
459 FETCH_OPS (SYNC_NAND_AND_FETCH_2, TSAN_ATOMIC16_FETCH_NAND, BIT_NOT_EXPR),
460 FETCH_OPS (SYNC_NAND_AND_FETCH_4, TSAN_ATOMIC32_FETCH_NAND, BIT_NOT_EXPR),
461 FETCH_OPS (SYNC_NAND_AND_FETCH_8, TSAN_ATOMIC64_FETCH_NAND, BIT_NOT_EXPR),
462 FETCH_OPS (SYNC_NAND_AND_FETCH_16, TSAN_ATOMIC128_FETCH_NAND, BIT_NOT_EXPR),
464 WEAK_CAS (ATOMIC_COMPARE_EXCHANGE_1, TSAN_ATOMIC8_COMPARE_EXCHANGE_WEAK),
465 WEAK_CAS (ATOMIC_COMPARE_EXCHANGE_2, TSAN_ATOMIC16_COMPARE_EXCHANGE_WEAK),
466 WEAK_CAS (ATOMIC_COMPARE_EXCHANGE_4, TSAN_ATOMIC32_COMPARE_EXCHANGE_WEAK),
467 WEAK_CAS (ATOMIC_COMPARE_EXCHANGE_8, TSAN_ATOMIC64_COMPARE_EXCHANGE_WEAK),
468 WEAK_CAS (ATOMIC_COMPARE_EXCHANGE_16, TSAN_ATOMIC128_COMPARE_EXCHANGE_WEAK),
470 STRONG_CAS (ATOMIC_COMPARE_EXCHANGE_1, TSAN_ATOMIC8_COMPARE_EXCHANGE_STRONG),
471 STRONG_CAS (ATOMIC_COMPARE_EXCHANGE_2,
472 TSAN_ATOMIC16_COMPARE_EXCHANGE_STRONG),
473 STRONG_CAS (ATOMIC_COMPARE_EXCHANGE_4,
474 TSAN_ATOMIC32_COMPARE_EXCHANGE_STRONG),
475 STRONG_CAS (ATOMIC_COMPARE_EXCHANGE_8,
476 TSAN_ATOMIC64_COMPARE_EXCHANGE_STRONG),
477 STRONG_CAS (ATOMIC_COMPARE_EXCHANGE_16,
478 TSAN_ATOMIC128_COMPARE_EXCHANGE_STRONG),
480 BOOL_CAS (SYNC_BOOL_COMPARE_AND_SWAP_1,
481 TSAN_ATOMIC8_COMPARE_EXCHANGE_STRONG),
482 BOOL_CAS (SYNC_BOOL_COMPARE_AND_SWAP_2,
483 TSAN_ATOMIC16_COMPARE_EXCHANGE_STRONG),
484 BOOL_CAS (SYNC_BOOL_COMPARE_AND_SWAP_4,
485 TSAN_ATOMIC32_COMPARE_EXCHANGE_STRONG),
486 BOOL_CAS (SYNC_BOOL_COMPARE_AND_SWAP_8,
487 TSAN_ATOMIC64_COMPARE_EXCHANGE_STRONG),
488 BOOL_CAS (SYNC_BOOL_COMPARE_AND_SWAP_16,
489 TSAN_ATOMIC128_COMPARE_EXCHANGE_STRONG),
491 VAL_CAS (SYNC_VAL_COMPARE_AND_SWAP_1, TSAN_ATOMIC8_COMPARE_EXCHANGE_STRONG),
492 VAL_CAS (SYNC_VAL_COMPARE_AND_SWAP_2, TSAN_ATOMIC16_COMPARE_EXCHANGE_STRONG),
493 VAL_CAS (SYNC_VAL_COMPARE_AND_SWAP_4, TSAN_ATOMIC32_COMPARE_EXCHANGE_STRONG),
494 VAL_CAS (SYNC_VAL_COMPARE_AND_SWAP_8, TSAN_ATOMIC64_COMPARE_EXCHANGE_STRONG),
495 VAL_CAS (SYNC_VAL_COMPARE_AND_SWAP_16,
496 TSAN_ATOMIC128_COMPARE_EXCHANGE_STRONG),
498 LOCK_RELEASE (SYNC_LOCK_RELEASE_1, TSAN_ATOMIC8_STORE),
499 LOCK_RELEASE (SYNC_LOCK_RELEASE_2, TSAN_ATOMIC16_STORE),
500 LOCK_RELEASE (SYNC_LOCK_RELEASE_4, TSAN_ATOMIC32_STORE),
501 LOCK_RELEASE (SYNC_LOCK_RELEASE_8, TSAN_ATOMIC64_STORE),
502 LOCK_RELEASE (SYNC_LOCK_RELEASE_16, TSAN_ATOMIC128_STORE)
505 /* Instrument an atomic builtin. */
507 static void
508 instrument_builtin_call (gimple_stmt_iterator *gsi)
510 gimple stmt = gsi_stmt (*gsi), g;
511 tree callee = gimple_call_fndecl (stmt), last_arg, args[6], t, lhs;
512 enum built_in_function fcode = DECL_FUNCTION_CODE (callee);
513 unsigned int i, num = gimple_call_num_args (stmt), j;
514 for (j = 0; j < 6 && j < num; j++)
515 args[j] = gimple_call_arg (stmt, j);
516 for (i = 0; i < ARRAY_SIZE (tsan_atomic_table); i++)
517 if (fcode != tsan_atomic_table[i].fcode)
518 continue;
519 else
521 tree decl = builtin_decl_implicit (tsan_atomic_table[i].tsan_fcode);
522 if (decl == NULL_TREE)
523 return;
524 switch (tsan_atomic_table[i].action)
526 case check_last:
527 case fetch_op:
528 last_arg = gimple_call_arg (stmt, num - 1);
529 if (!tree_fits_uhwi_p (last_arg)
530 || tree_to_uhwi (last_arg) > MEMMODEL_SEQ_CST)
531 return;
532 gimple_call_set_fndecl (stmt, decl);
533 update_stmt (stmt);
534 if (tsan_atomic_table[i].action == fetch_op)
536 args[1] = gimple_call_arg (stmt, 1);
537 goto adjust_result;
539 return;
540 case add_seq_cst:
541 case add_acquire:
542 case fetch_op_seq_cst:
543 gcc_assert (num <= 2);
544 for (j = 0; j < num; j++)
545 args[j] = gimple_call_arg (stmt, j);
546 for (; j < 2; j++)
547 args[j] = NULL_TREE;
548 args[num] = build_int_cst (NULL_TREE,
549 tsan_atomic_table[i].action
550 != add_acquire
551 ? MEMMODEL_SEQ_CST
552 : MEMMODEL_ACQUIRE);
553 update_gimple_call (gsi, decl, num + 1, args[0], args[1], args[2]);
554 stmt = gsi_stmt (*gsi);
555 if (tsan_atomic_table[i].action == fetch_op_seq_cst)
557 adjust_result:
558 lhs = gimple_call_lhs (stmt);
559 if (lhs == NULL_TREE)
560 return;
561 if (!useless_type_conversion_p (TREE_TYPE (lhs),
562 TREE_TYPE (args[1])))
564 tree var = make_ssa_name (TREE_TYPE (lhs));
565 g = gimple_build_assign (var, NOP_EXPR, args[1]);
566 gsi_insert_after (gsi, g, GSI_NEW_STMT);
567 args[1] = var;
569 gimple_call_set_lhs (stmt, make_ssa_name (TREE_TYPE (lhs)));
570 /* BIT_NOT_EXPR stands for NAND. */
571 if (tsan_atomic_table[i].code == BIT_NOT_EXPR)
573 tree var = make_ssa_name (TREE_TYPE (lhs));
574 g = gimple_build_assign (var, BIT_AND_EXPR,
575 gimple_call_lhs (stmt), args[1]);
576 gsi_insert_after (gsi, g, GSI_NEW_STMT);
577 g = gimple_build_assign (lhs, BIT_NOT_EXPR, var);
579 else
580 g = gimple_build_assign (lhs, tsan_atomic_table[i].code,
581 gimple_call_lhs (stmt), args[1]);
582 update_stmt (stmt);
583 gsi_insert_after (gsi, g, GSI_NEW_STMT);
585 return;
586 case weak_cas:
587 if (!integer_nonzerop (gimple_call_arg (stmt, 3)))
588 continue;
589 /* FALLTHRU */
590 case strong_cas:
591 gcc_assert (num == 6);
592 for (j = 0; j < 6; j++)
593 args[j] = gimple_call_arg (stmt, j);
594 if (!tree_fits_uhwi_p (args[4])
595 || tree_to_uhwi (args[4]) > MEMMODEL_SEQ_CST)
596 return;
597 if (!tree_fits_uhwi_p (args[5])
598 || tree_to_uhwi (args[5]) > MEMMODEL_SEQ_CST)
599 return;
600 update_gimple_call (gsi, decl, 5, args[0], args[1], args[2],
601 args[4], args[5]);
602 return;
603 case bool_cas:
604 case val_cas:
605 gcc_assert (num == 3);
606 for (j = 0; j < 3; j++)
607 args[j] = gimple_call_arg (stmt, j);
608 t = TYPE_ARG_TYPES (TREE_TYPE (decl));
609 t = TREE_VALUE (TREE_CHAIN (TREE_CHAIN (t)));
610 t = create_tmp_var (t);
611 mark_addressable (t);
612 if (!useless_type_conversion_p (TREE_TYPE (t),
613 TREE_TYPE (args[1])))
615 g = gimple_build_assign (make_ssa_name (TREE_TYPE (t)),
616 NOP_EXPR, args[1]);
617 gsi_insert_before (gsi, g, GSI_SAME_STMT);
618 args[1] = gimple_assign_lhs (g);
620 g = gimple_build_assign (t, args[1]);
621 gsi_insert_before (gsi, g, GSI_SAME_STMT);
622 lhs = gimple_call_lhs (stmt);
623 update_gimple_call (gsi, decl, 5, args[0],
624 build_fold_addr_expr (t), args[2],
625 build_int_cst (NULL_TREE,
626 MEMMODEL_SEQ_CST),
627 build_int_cst (NULL_TREE,
628 MEMMODEL_SEQ_CST));
629 if (tsan_atomic_table[i].action == val_cas && lhs)
631 tree cond;
632 stmt = gsi_stmt (*gsi);
633 g = gimple_build_assign (make_ssa_name (TREE_TYPE (t)), t);
634 gsi_insert_after (gsi, g, GSI_NEW_STMT);
635 t = make_ssa_name (TREE_TYPE (TREE_TYPE (decl)), stmt);
636 cond = build2 (NE_EXPR, boolean_type_node, t,
637 build_int_cst (TREE_TYPE (t), 0));
638 g = gimple_build_assign (lhs, COND_EXPR, cond, args[1],
639 gimple_assign_lhs (g));
640 gimple_call_set_lhs (stmt, t);
641 update_stmt (stmt);
642 gsi_insert_after (gsi, g, GSI_NEW_STMT);
644 return;
645 case lock_release:
646 gcc_assert (num == 1);
647 t = TYPE_ARG_TYPES (TREE_TYPE (decl));
648 t = TREE_VALUE (TREE_CHAIN (t));
649 update_gimple_call (gsi, decl, 3, gimple_call_arg (stmt, 0),
650 build_int_cst (t, 0),
651 build_int_cst (NULL_TREE,
652 MEMMODEL_RELEASE));
653 return;
654 default:
655 continue;
660 /* Instruments the gimple pointed to by GSI. Return
661 true if func entry/exit should be instrumented. */
663 static bool
664 instrument_gimple (gimple_stmt_iterator *gsi)
666 gimple stmt;
667 tree rhs, lhs;
668 bool instrumented = false;
670 stmt = gsi_stmt (*gsi);
671 if (is_gimple_call (stmt)
672 && (gimple_call_fndecl (stmt)
673 != builtin_decl_implicit (BUILT_IN_TSAN_INIT)))
675 if (gimple_call_builtin_p (stmt, BUILT_IN_NORMAL))
676 instrument_builtin_call (gsi);
677 return true;
679 else if (is_gimple_assign (stmt)
680 && !gimple_clobber_p (stmt))
682 if (gimple_store_p (stmt))
684 lhs = gimple_assign_lhs (stmt);
685 instrumented = instrument_expr (*gsi, lhs, true);
687 if (gimple_assign_load_p (stmt))
689 rhs = gimple_assign_rhs1 (stmt);
690 instrumented = instrument_expr (*gsi, rhs, false);
693 return instrumented;
696 /* Instruments all interesting memory accesses in the current function.
697 Return true if func entry/exit should be instrumented. */
699 static bool
700 instrument_memory_accesses (void)
702 basic_block bb;
703 gimple_stmt_iterator gsi;
704 bool fentry_exit_instrument = false;
706 FOR_EACH_BB_FN (bb, cfun)
707 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
708 fentry_exit_instrument |= instrument_gimple (&gsi);
709 return fentry_exit_instrument;
712 /* Instruments function entry. */
714 static void
715 instrument_func_entry (void)
717 tree ret_addr, builtin_decl;
718 gimple g;
719 gimple_seq seq = NULL;
721 builtin_decl = builtin_decl_implicit (BUILT_IN_RETURN_ADDRESS);
722 g = gimple_build_call (builtin_decl, 1, integer_zero_node);
723 ret_addr = make_ssa_name (ptr_type_node);
724 gimple_call_set_lhs (g, ret_addr);
725 gimple_set_location (g, cfun->function_start_locus);
726 gimple_seq_add_stmt_without_update (&seq, g);
728 builtin_decl = builtin_decl_implicit (BUILT_IN_TSAN_FUNC_ENTRY);
729 g = gimple_build_call (builtin_decl, 1, ret_addr);
730 gimple_set_location (g, cfun->function_start_locus);
731 gimple_seq_add_stmt_without_update (&seq, g);
733 edge e = single_succ_edge (ENTRY_BLOCK_PTR_FOR_FN (cfun));
734 gsi_insert_seq_on_edge_immediate (e, seq);
737 /* Instruments function exits. */
739 static void
740 instrument_func_exit (void)
742 location_t loc;
743 basic_block exit_bb;
744 gimple_stmt_iterator gsi;
745 gimple stmt, g;
746 tree builtin_decl;
747 edge e;
748 edge_iterator ei;
750 /* Find all function exits. */
751 exit_bb = EXIT_BLOCK_PTR_FOR_FN (cfun);
752 FOR_EACH_EDGE (e, ei, exit_bb->preds)
754 gsi = gsi_last_bb (e->src);
755 stmt = gsi_stmt (gsi);
756 gcc_assert (gimple_code (stmt) == GIMPLE_RETURN
757 || gimple_call_builtin_p (stmt, BUILT_IN_RETURN));
758 loc = gimple_location (stmt);
759 builtin_decl = builtin_decl_implicit (BUILT_IN_TSAN_FUNC_EXIT);
760 g = gimple_build_call (builtin_decl, 0);
761 gimple_set_location (g, loc);
762 gsi_insert_before (&gsi, g, GSI_SAME_STMT);
766 /* ThreadSanitizer instrumentation pass. */
768 static unsigned
769 tsan_pass (void)
771 initialize_sanitizer_builtins ();
772 if (instrument_memory_accesses ())
774 instrument_func_entry ();
775 instrument_func_exit ();
777 return 0;
780 /* Inserts __tsan_init () into the list of CTORs. */
782 void
783 tsan_finish_file (void)
785 tree ctor_statements = NULL_TREE;
787 initialize_sanitizer_builtins ();
788 tree init_decl = builtin_decl_implicit (BUILT_IN_TSAN_INIT);
789 append_to_statement_list (build_call_expr (init_decl, 0),
790 &ctor_statements);
791 cgraph_build_static_cdtor ('I', ctor_statements,
792 MAX_RESERVED_INIT_PRIORITY - 1);
795 /* The pass descriptor. */
797 namespace {
799 const pass_data pass_data_tsan =
801 GIMPLE_PASS, /* type */
802 "tsan", /* name */
803 OPTGROUP_NONE, /* optinfo_flags */
804 TV_NONE, /* tv_id */
805 ( PROP_ssa | PROP_cfg ), /* properties_required */
806 0, /* properties_provided */
807 0, /* properties_destroyed */
808 0, /* todo_flags_start */
809 TODO_update_ssa, /* todo_flags_finish */
812 class pass_tsan : public gimple_opt_pass
814 public:
815 pass_tsan (gcc::context *ctxt)
816 : gimple_opt_pass (pass_data_tsan, ctxt)
819 /* opt_pass methods: */
820 opt_pass * clone () { return new pass_tsan (m_ctxt); }
821 virtual bool gate (function *)
823 return (flag_sanitize & SANITIZE_THREAD) != 0;
826 virtual unsigned int execute (function *) { return tsan_pass (); }
828 }; // class pass_tsan
830 } // anon namespace
832 gimple_opt_pass *
833 make_pass_tsan (gcc::context *ctxt)
835 return new pass_tsan (ctxt);
838 namespace {
840 const pass_data pass_data_tsan_O0 =
842 GIMPLE_PASS, /* type */
843 "tsan0", /* name */
844 OPTGROUP_NONE, /* optinfo_flags */
845 TV_NONE, /* tv_id */
846 ( PROP_ssa | PROP_cfg ), /* properties_required */
847 0, /* properties_provided */
848 0, /* properties_destroyed */
849 0, /* todo_flags_start */
850 TODO_update_ssa, /* todo_flags_finish */
853 class pass_tsan_O0 : public gimple_opt_pass
855 public:
856 pass_tsan_O0 (gcc::context *ctxt)
857 : gimple_opt_pass (pass_data_tsan_O0, ctxt)
860 /* opt_pass methods: */
861 virtual bool gate (function *)
863 return (flag_sanitize & SANITIZE_THREAD) != 0 && !optimize;
866 virtual unsigned int execute (function *) { return tsan_pass (); }
868 }; // class pass_tsan_O0
870 } // anon namespace
872 gimple_opt_pass *
873 make_pass_tsan_O0 (gcc::context *ctxt)
875 return new pass_tsan_O0 (ctxt);