1 files changed, 86 insertions, 0 deletions
diff --git a/test/tsan/fiber_asm.cc b/test/tsan/fiber_asm.cc
new file mode 100644
index 000000000..63b63d382
--- /dev/null
+++ b/test/tsan/fiber_asm.cc
@@ -0,0 +1,86 @@
+// RUN: %clang_tsan -O1 %s -o %t && %run %t 2>&1 | FileCheck %s
+// REQUIRES: x86_64-target-arch
+// UNSUPPORTED: tvos, watchos
+#include "test.h"
+
+struct ucontext {
+  void *sp;
+  void *fiber;
+};
+
+extern "C" {
+  void ucontext_do_switch(void **save, void **load);
+  void ucontext_trampoline();
+}
+
+__asm__(".global " ASM_SYMBOL(ucontext_do_switch) "\n"
+        ASM_SYMBOL(ucontext_do_switch) ":\n\t"
+        "pushq %rbp\n\t"
+        "pushq %r15\n\t"
+        "pushq %r14\n\t"
+        "pushq %r13\n\t"
+        "pushq %r12\n\t"
+        "pushq %rbx\n\t"
+        "movq %rsp, (%rdi)\n\t"
+        "movq (%rsi), %rsp\n\t"
+        "popq %rbx\n\t"
+        "popq %r12\n\t"
+        "popq %r13\n\t"
+        "popq %r14\n\t"
+        "popq %r15\n\t"
+        "popq %rbp\n\t"
+        "retq");
+
+__asm__(".global " ASM_SYMBOL(ucontext_trampoline) "\n"
+        ASM_SYMBOL(ucontext_trampoline) ":\n\t"
+        ".cfi_startproc\n\t"
+        ".cfi_undefined rip\n\t"
+        "movq %r12, %rdi\n\t"
+        "jmpq *%rbx\n\t"
+        ".cfi_endproc");
+
+void ucontext_init(ucontext *context, void *stack, unsigned stack_sz,
+                   void (*func)(void*), void *arg) {
+  void **sp = reinterpret_cast<void **>(static_cast<char *>(stack) + stack_sz);
+  *(--sp) = 0;
+  *(--sp) = reinterpret_cast<void *>(ucontext_trampoline);
+  *(--sp) = 0;   // rbp
+  *(--sp) = 0;   // r15
+  *(--sp) = 0;   // r14
+  *(--sp) = 0;   // r13
+  *(--sp) = arg; // r12
+  *(--sp) = reinterpret_cast<void *>(func); // rbx
+  context->sp = sp;
+  context->fiber = __tsan_create_fiber(0);
+}
+
+void ucontext_free(ucontext *context) {
+  __tsan_destroy_fiber(context->fiber);
+}
+
+__attribute__((no_sanitize_thread))
+void ucontext_switch(ucontext *save, ucontext *load) {
+  save->fiber = __tsan_get_current_fiber();
+  __tsan_switch_to_fiber(load->fiber, 0);
+  ucontext_do_switch(&save->sp, &load->sp);
+}
+
+char stack[64 * 1024] __attribute__((aligned(16)));
+
+ucontext uc, orig_uc;
+
+void func(void *arg) {
+  __asm__ __volatile__(".cfi_undefined rip");
+  ucontext_switch(&uc, &orig_uc);
+}
+
+int main() {
+  ucontext_init(&uc, stack, sizeof(stack), func, 0);
+  ucontext_switch(&orig_uc, &uc);
+  ucontext_free(&uc);
+  fprintf(stderr, "PASS\n");
+  return 0;
+}
+
+// CHECK-NOT: WARNING: ThreadSanitizer:
+// CHECK: PASS