1// RUN: %clang_tsan -O1 %s -o %t && %run %t 2>&1 | FileCheck %s
2// REQUIRES: x86_64-target-arch
3// UNSUPPORTED: tvos, watchos
4#include "test.h"
5
6struct ucontext {
7 void *sp;
8 void *fiber;
9};
10
11extern "C" {
12 void ucontext_do_switch(void **save, void **load);
13 void ucontext_trampoline();
14}
15
16__asm__(".global " ASM_SYMBOL(ucontext_do_switch) "\n"
17 ASM_SYMBOL(ucontext_do_switch) ":\n\t"
18 "pushq %rbp\n\t"
19 "pushq %r15\n\t"
20 "pushq %r14\n\t"
21 "pushq %r13\n\t"
22 "pushq %r12\n\t"
23 "pushq %rbx\n\t"
24 "movq %rsp, (%rdi)\n\t"
25 "movq (%rsi), %rsp\n\t"
26 "popq %rbx\n\t"
27 "popq %r12\n\t"
28 "popq %r13\n\t"
29 "popq %r14\n\t"
30 "popq %r15\n\t"
31 "popq %rbp\n\t"
32 "retq");
33
34__asm__(".global " ASM_SYMBOL(ucontext_trampoline) "\n"
35 ASM_SYMBOL(ucontext_trampoline) ":\n\t"
36 ".cfi_startproc\n\t"
37 ".cfi_undefined rip\n\t"
38 "movq %r12, %rdi\n\t"
39 "jmpq *%rbx\n\t"
40 ".cfi_endproc");
41
42void ucontext_init(ucontext *context, void *stack, unsigned stack_sz,
43 void (*func)(void*), void *arg) {
44 void **sp = reinterpret_cast<void **>(static_cast<char *>(stack) + stack_sz);
45 *(--sp) = 0;
46 *(--sp) = reinterpret_cast<void *>(ucontext_trampoline);
47 *(--sp) = 0; // rbp
48 *(--sp) = 0; // r15
49 *(--sp) = 0; // r14
50 *(--sp) = 0; // r13
51 *(--sp) = arg; // r12
52 *(--sp) = reinterpret_cast<void *>(func); // rbx
53 context->sp = sp;
54 context->fiber = __tsan_create_fiber(0);
55}
56
57void ucontext_free(ucontext *context) {
58 __tsan_destroy_fiber(context->fiber);
59}
60
61__attribute__((no_sanitize_thread))
62void ucontext_switch(ucontext *save, ucontext *load) {
63 save->fiber = __tsan_get_current_fiber();
64 __tsan_switch_to_fiber(load->fiber, 0);
65 ucontext_do_switch(&save->sp, &load->sp);
66}
67
68char stack[64 * 1024] __attribute__((aligned(16)));
69
70ucontext uc, orig_uc;
71
72void func(void *arg) {
73 __asm__ __volatile__(".cfi_undefined rip");
74 ucontext_switch(&uc, &orig_uc);
75}
76
77int main() {
78 ucontext_init(&uc, stack, sizeof(stack), func, 0);
79 ucontext_switch(&orig_uc, &uc);
80 ucontext_free(&uc);
81 fprintf(stderr, "PASS\n");
82 return 0;
83}
84
85// CHECK-NOT: WARNING: ThreadSanitizer:
86// CHECK: PASS
87