compiler-rt/test/tsan/fiber_asm.cpp

   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(0);
  55 }
  56
  57 void ucontext_free(ucontext *context) {
  58   __tsan_destroy_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(load->fiber, 0);
  65   ucontext_do_switch(&save->sp, &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(&uc, &orig_uc);
  75 }
  76
  77 int 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