libunwind/src/cet_unwind.h

   1 //===----------------------------------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //
   8 //===----------------------------------------------------------------------===//
   9
  10 #ifndef LIBUNWIND_CET_UNWIND_H
  11 #define LIBUNWIND_CET_UNWIND_H
  12
  13 #include "libunwind.h"
  14
  15 // Currently, CET is implemented on Linux x86 platforms.
  16 #if defined(_LIBUNWIND_TARGET_LINUX) && defined(__CET__) && defined(__SHSTK__)
  17 #define _LIBUNWIND_USE_CET 1
  18 #endif
  19
  20 #if defined(_LIBUNWIND_USE_CET)
  21 #include <cet.h>
  22 #include <immintrin.h>
  23
  24 #define _LIBUNWIND_POP_CET_SSP(x)                                              \
  25   do {                                                                         \
  26     unsigned long ssp = _get_ssp();                                            \
  27     if (ssp != 0) {                                                            \
  28       unsigned int tmp = (x);                                                  \
  29       while (tmp > 255) {                                                      \
  30         _inc_ssp(255);                                                         \
  31         tmp -= 255;                                                            \
  32       }                                                                        \
  33       _inc_ssp(tmp);                                                           \
  34     }                                                                          \
  35   } while (0)
  36 #endif
  37
  38 extern void *__libunwind_cet_get_registers(unw_cursor_t *);
  39 extern void *__libunwind_cet_get_jump_target(void);
  40
  41 #endif