1  //===-- sanitizer_asm.h -----------------------------------------*- C++ -*-===//
       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  // Various support for assembler.
      10  //
      11  //===----------------------------------------------------------------------===//
      12  
      13  // Some toolchains do not support .cfi asm directives, so we have to hide
      14  // them inside macros.
      15  #if defined(__clang__) ||                                                      \
      16      (defined(__GNUC__) && defined(__GCC_HAVE_DWARF2_CFI_ASM))
      17    // GCC defined __GCC_HAVE_DWARF2_CFI_ASM if it supports CFI.
      18    // Clang seems to support CFI by default (or not?).
      19    // We need two versions of macros: for inline asm and standalone asm files.
      20  # define CFI_INL_ADJUST_CFA_OFFSET(n) ".cfi_adjust_cfa_offset " #n ";"
      21  
      22  # define CFI_STARTPROC .cfi_startproc
      23  # define CFI_ENDPROC .cfi_endproc
      24  # define CFI_ADJUST_CFA_OFFSET(n) .cfi_adjust_cfa_offset n
      25  # define CFI_DEF_CFA_OFFSET(n) .cfi_def_cfa_offset n
      26  # define CFI_REL_OFFSET(reg, n) .cfi_rel_offset reg, n
      27  # define CFI_OFFSET(reg, n) .cfi_offset reg, n
      28  # define CFI_DEF_CFA_REGISTER(reg) .cfi_def_cfa_register reg
      29  # define CFI_DEF_CFA(reg, n) .cfi_def_cfa reg, n
      30  # define CFI_RESTORE(reg) .cfi_restore reg
      31  
      32  #else  // No CFI
      33  # define CFI_INL_ADJUST_CFA_OFFSET(n)
      34  # define CFI_STARTPROC
      35  # define CFI_ENDPROC
      36  # define CFI_ADJUST_CFA_OFFSET(n)
      37  # define CFI_DEF_CFA_OFFSET(n)
      38  # define CFI_REL_OFFSET(reg, n)
      39  # define CFI_OFFSET(reg, n)
      40  # define CFI_DEF_CFA_REGISTER(reg)
      41  # define CFI_DEF_CFA(reg, n)
      42  # define CFI_RESTORE(reg)
      43  #endif
      44  
      45  #if !defined(__APPLE__)
      46  # define ASM_HIDDEN(symbol) .hidden symbol
      47  # define ASM_TYPE_FUNCTION(symbol) .type symbol, %function
      48  # define ASM_SIZE(symbol) .size symbol, .-symbol
      49  # define ASM_SYMBOL(symbol) symbol
      50  # define ASM_SYMBOL_INTERCEPTOR(symbol) symbol
      51  # define ASM_WRAPPER_NAME(symbol) __interceptor_##symbol
      52  #else
      53  # define ASM_HIDDEN(symbol)
      54  # define ASM_TYPE_FUNCTION(symbol)
      55  # define ASM_SIZE(symbol)
      56  # define ASM_SYMBOL(symbol) _##symbol
      57  # define ASM_SYMBOL_INTERCEPTOR(symbol) _wrap_##symbol
      58  # define ASM_WRAPPER_NAME(symbol) __interceptor_##symbol
      59  #endif
      60  
      61  #if defined(__ELF__) && (defined(__GNU__) || defined(__FreeBSD__) || \
      62                           defined(__Fuchsia__) || defined(__linux__))
      63  // clang-format off
      64  #define NO_EXEC_STACK_DIRECTIVE .section .note.GNU-stack,"",%progbits
      65  // clang-format on
      66  #else
      67  #define NO_EXEC_STACK_DIRECTIVE
      68  #endif
      69  
      70  #if (defined(__x86_64__) || defined(__i386__)) && defined(__has_include) && __has_include(<cet.h>)
      71  #include <cet.h>
      72  #endif
      73  #ifndef _CET_ENDBR
      74  #define _CET_ENDBR
      75  #endif