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 // On AArch64 we use _LIBUNWIND_USE_GCS to indicate that GCS is supported. We 39 // need to guard any use of GCS instructions with __chkfeat though, as GCS may 40 // not be enabled. 41 #if defined(_LIBUNWIND_TARGET_AARCH64) && defined(__ARM_FEATURE_GCS_DEFAULT) 42 #include <arm_acle.h> 43 44 // We can only use GCS if arm_acle.h defines the GCS intrinsics. 45 #ifdef _CHKFEAT_GCS 46 #define _LIBUNWIND_USE_GCS 1 47 #endif 48 49 #define _LIBUNWIND_POP_CET_SSP(x) \ 50 do { \ 51 if (__chkfeat(_CHKFEAT_GCS)) { \ 52 unsigned tmp = (x); \ 53 while (tmp--) \ 54 __gcspopm(); \ 55 } \ 56 } while (0) 57 58 #endif 59 60 extern void *__libunwind_cet_get_registers(unw_cursor_t *); 61 extern void *__libunwind_cet_get_jump_target(void); 62 63 #endif 64