| //===-- sanitizer_asm.h -----------------------------------------*- C++ -*-===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // Various support for assembler. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| // Some toolchains do not support .cfi asm directives, so we have to hide |
| // them inside macros. |
| #if defined(__clang__) || \ |
| (defined(__GNUC__) && defined(__GCC_HAVE_DWARF2_CFI_ASM)) |
| // GCC defined __GCC_HAVE_DWARF2_CFI_ASM if it supports CFI. |
| // Clang seems to support CFI by default (or not?). |
| // We need two versions of macros: for inline asm and standalone asm files. |
| # define CFI_INL_ADJUST_CFA_OFFSET(n) ".cfi_adjust_cfa_offset " #n ";" |
| |
| # define CFI_STARTPROC .cfi_startproc |
| # define CFI_ENDPROC .cfi_endproc |
| # define CFI_ADJUST_CFA_OFFSET(n) .cfi_adjust_cfa_offset n |
| # define CFI_DEF_CFA_OFFSET(n) .cfi_def_cfa_offset n |
| # define CFI_REL_OFFSET(reg, n) .cfi_rel_offset reg, n |
| # define CFI_OFFSET(reg, n) .cfi_offset reg, n |
| # define CFI_DEF_CFA_REGISTER(reg) .cfi_def_cfa_register reg |
| # define CFI_DEF_CFA(reg, n) .cfi_def_cfa reg, n |
| # define CFI_RESTORE(reg) .cfi_restore reg |
| |
| #else // No CFI |
| # define CFI_INL_ADJUST_CFA_OFFSET(n) |
| # define CFI_STARTPROC |
| # define CFI_ENDPROC |
| # define CFI_ADJUST_CFA_OFFSET(n) |
| # define CFI_DEF_CFA_OFFSET(n) |
| # define CFI_REL_OFFSET(reg, n) |
| # define CFI_OFFSET(reg, n) |
| # define CFI_DEF_CFA_REGISTER(reg) |
| # define CFI_DEF_CFA(reg, n) |
| # define CFI_RESTORE(reg) |
| #endif |
| |
| #if defined(__x86_64__) || defined(__i386__) || defined(__sparc__) |
| # define ASM_TAIL_CALL jmp |
| #elif defined(__arm__) || defined(__aarch64__) || defined(__mips__) || \ |
| defined(__powerpc__) || defined(__loongarch_lp64) |
| # define ASM_TAIL_CALL b |
| #elif defined(__s390__) |
| # define ASM_TAIL_CALL jg |
| #elif defined(__riscv) |
| # define ASM_TAIL_CALL tail |
| #endif |
| |
| #if defined(__ELF__) && defined(__x86_64__) || defined(__i386__) || \ |
| defined(__riscv) |
| # define ASM_PREEMPTIBLE_SYM(sym) sym@plt |
| #else |
| # define ASM_PREEMPTIBLE_SYM(sym) sym |
| #endif |
| |
| #if !defined(__APPLE__) |
| # define ASM_HIDDEN(symbol) .hidden symbol |
| # if defined(__arm__) || defined(__aarch64__) |
| # define ASM_TYPE_FUNCTION(symbol) .type symbol, %function |
| # else |
| # define ASM_TYPE_FUNCTION(symbol) .type symbol, @function |
| # endif |
| # define ASM_SIZE(symbol) .size symbol, .-symbol |
| # define ASM_SYMBOL(symbol) symbol |
| # define ASM_SYMBOL_INTERCEPTOR(symbol) symbol |
| # if defined(__i386__) || defined(__powerpc__) || defined(__s390__) || \ |
| defined(__sparc__) |
| // For details, see interception.h |
| # define ASM_WRAPPER_NAME(symbol) __interceptor_##symbol |
| # define ASM_TRAMPOLINE_ALIAS(symbol, name) \ |
| .weak symbol; \ |
| .set symbol, ASM_WRAPPER_NAME(name) |
| # define ASM_INTERCEPTOR_TRAMPOLINE(name) |
| # define ASM_INTERCEPTOR_TRAMPOLINE_SUPPORT 0 |
| # else // Architecture supports interceptor trampoline |
| // Keep trampoline implementation in sync with interception/interception.h |
| # define ASM_WRAPPER_NAME(symbol) ___interceptor_##symbol |
| # define ASM_TRAMPOLINE_ALIAS(symbol, name) \ |
| .weak symbol; \ |
| .set symbol, __interceptor_trampoline_##name |
| # define ASM_INTERCEPTOR_TRAMPOLINE(name) \ |
| .weak __interceptor_##name; \ |
| .set __interceptor_##name, ASM_WRAPPER_NAME(name); \ |
| .globl __interceptor_trampoline_##name; \ |
| ASM_TYPE_FUNCTION(__interceptor_trampoline_##name); \ |
| __interceptor_trampoline_##name: \ |
| CFI_STARTPROC; \ |
| ASM_TAIL_CALL ASM_PREEMPTIBLE_SYM(__interceptor_##name); \ |
| CFI_ENDPROC; \ |
| ASM_SIZE(__interceptor_trampoline_##name) |
| # define ASM_INTERCEPTOR_TRAMPOLINE_SUPPORT 1 |
| # endif // Architecture supports interceptor trampoline |
| #else |
| # define ASM_HIDDEN(symbol) |
| # define ASM_TYPE_FUNCTION(symbol) |
| # define ASM_SIZE(symbol) |
| # define ASM_SYMBOL(symbol) _##symbol |
| # define ASM_SYMBOL_INTERCEPTOR(symbol) _wrap_##symbol |
| # define ASM_WRAPPER_NAME(symbol) __interceptor_##symbol |
| #endif |
| |
| #if defined(__ELF__) && (defined(__GNU__) || defined(__FreeBSD__) || \ |
| defined(__Fuchsia__) || defined(__linux__)) |
| // clang-format off |
| #define NO_EXEC_STACK_DIRECTIVE .section .note.GNU-stack,"",%progbits |
| // clang-format on |
| #else |
| #define NO_EXEC_STACK_DIRECTIVE |
| #endif |
| |
| #if (defined(__x86_64__) || defined(__i386__)) && defined(__has_include) && __has_include(<cet.h>) |
| #include <cet.h> |
| #endif |
| #ifndef _CET_ENDBR |
| #define _CET_ENDBR |
| #endif |