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| // 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
|