| 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 | |
| 6 | struct ucontext { |
| 7 | void *sp; |
| 8 | void *fiber; |
| 9 | }; |
| 10 | |
| 11 | extern "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 | |
| 42 | void 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(flags: 0); |
| 55 | } |
| 56 | |
| 57 | void ucontext_free(ucontext *context) { |
| 58 | __tsan_destroy_fiber(fiber: context->fiber); |
| 59 | } |
| 60 | |
| 61 | __attribute__((no_sanitize_thread)) |
| 62 | void ucontext_switch(ucontext *save, ucontext *load) { |
| 63 | save->fiber = __tsan_get_current_fiber(); |
| 64 | __tsan_switch_to_fiber(fiber: load->fiber, flags: 0); |
| 65 | ucontext_do_switch(save: &save->sp, load: &load->sp); |
| 66 | } |
| 67 | |
| 68 | char stack[64 * 1024] __attribute__((aligned(16))); |
| 69 | |
| 70 | ucontext uc, orig_uc; |
| 71 | |
| 72 | void func(void *arg) { |
| 73 | __asm__ __volatile__(".cfi_undefined rip" ); |
| 74 | ucontext_switch(save: &uc, load: &orig_uc); |
| 75 | } |
| 76 | |
| 77 | int main() { |
| 78 | ucontext_init(context: &uc, stack, stack_sz: sizeof(stack), func, arg: 0); |
| 79 | ucontext_switch(save: &orig_uc, load: &uc); |
| 80 | ucontext_free(context: &uc); |
| 81 | fprintf(stderr, format: "PASS\n" ); |
| 82 | return 0; |
| 83 | } |
| 84 | |
| 85 | // CHECK-NOT: WARNING: ThreadSanitizer: |
| 86 | // CHECK: PASS |
| 87 | |