a7cad4fcb7
This patch allows the Swift compiler to emit calls to `__tsan_external_write` before starting any modifying access, which will cause TSan to detect races on arrays, dictionaries and other classes defined in non-instrumented modules. Races on collections from the Swift standard library and user-defined structs and a frequent cause of subtle bugs and it's important that TSan detects those on top of existing LLVM IR instrumentation, which already detects races in direct memory accesses. Differential Revision: https://reviews.llvm.org/D31630 llvm-svn: 302050
59 lines
1.4 KiB
C++
59 lines
1.4 KiB
C++
// RUN: %clangxx_tsan %s -o %t
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// RUN: %deflake %run %t 2>&1 | FileCheck %s
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#include <thread>
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#import "../test.h"
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void *tag;
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__attribute__((no_sanitize("thread")))
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void ExternalWrite(void *addr) {
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__tsan_external_write(addr, __builtin_return_address(0), tag);
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}
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int main(int argc, char *argv[]) {
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barrier_init(&barrier, 2);
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tag = __tsan_external_register_tag("HelloWorld");
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fprintf(stderr, "Start.\n");
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// CHECK: Start.
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for (int i = 0; i < 4; i++) {
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void *opaque_object = malloc(16);
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std::thread t1([opaque_object] {
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ExternalWrite(opaque_object);
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barrier_wait(&barrier);
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});
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std::thread t2([opaque_object] {
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barrier_wait(&barrier);
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ExternalWrite(opaque_object);
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});
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// CHECK: WARNING: ThreadSanitizer: race on HelloWorld
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t1.join();
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t2.join();
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}
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fprintf(stderr, "First phase done.\n");
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// CHECK: First phase done.
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for (int i = 0; i < 4; i++) {
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void *opaque_object = malloc(16);
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std::thread t1([opaque_object] {
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ExternalWrite(opaque_object);
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barrier_wait(&barrier);
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});
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std::thread t2([opaque_object] {
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barrier_wait(&barrier);
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ExternalWrite(opaque_object);
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});
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// CHECK: WARNING: ThreadSanitizer: race on HelloWorld
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t1.join();
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t2.join();
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}
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fprintf(stderr, "Second phase done.\n");
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// CHECK: Second phase done.
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}
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// CHECK: ThreadSanitizer: reported 2 warnings
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