libcxxabi/test/native/AArch64/ra_sign_state.pass.cpp

   1 // -*- C++ -*-
   2 //===----------------------------------------------------------------------===//
   3 //
   4 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   5 // See https://llvm.org/LICENSE.txt for license information.
   6 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   7 //
   8 //===----------------------------------------------------------------------===//
   9
  10 // REQUIRES: linux && target={{aarch64-.+}}
  11 // XFAIL: no-exceptions
  12
  13 // This test ensures the .cfi_negate_ra_state the RA_SIGN_STATE pseudo register
  14 // could be set directly set by a DWARF expression and the unwinder handles it
  15 // correctly. The two directives can't be mixed in one CIE/FDE sqeuence.
  16
  17 #include <stdlib.h>
  18
  19 __attribute__((noinline, target("branch-protection=pac-ret+leaf")))
  20 void bar() {
  21   // ".cfi_negate_ra_state" is emitted by the compiler.
  22   throw 1;
  23 }
  24
  25 __attribute__((noinline, target("branch-protection=none")))
  26 void foo() {
  27   // Here a DWARF expression sets RA_SIGN_STATE.
  28   // The LR is signed manually and stored on the stack.
  29   asm volatile(
  30       ".cfi_escape 0x16,"    // DW_CFA_val_expression
  31                     "34,"    // REG_34(RA_SIGN_STATE)
  32                      "1,"    // expression_length(1)
  33                     "0x31\n" // DW_OP_lit1
  34       "add sp, sp, 16\n"     // Restore SP's value before the stack frame is
  35                              // created.
  36       "paciasp\n"            // Sign the LR.
  37       "str lr, [sp, -0x8]\n" // Overwrite LR on the stack.
  38       "sub sp, sp, 16\n"     // Restore SP's value.
  39   );
  40   bar();
  41   _Exit(-1);
  42 }
  43
  44 __attribute__((noinline, target("branch-protection=pac-ret")))
  45 void bazz() {
  46   // ".cfi_negate_ra_state" is emitted by the compiler.
  47   try {
  48     foo();
  49   } catch (int i) {
  50     if (i == 1)
  51       throw i;
  52     throw 2;
  53   }
  54 }
  55
  56 int main() {
  57   try {
  58     bazz();
  59   } catch (int i) {
  60     if (i == 1)
  61       _Exit(0);
  62   }
  63   return -1;
  64 }