platform_bionic/libc/private/bionic_asm.h
Elliott Hughes d7831208b2 Fix assembler warnings.
clang complains if you define a symbol and _then_ make it weak, rather
than the other way round:

  /tmp/setjmp-c3c977.s:90:1: warning: sigsetjmp changed binding to STB_WEAK
  .weak sigsetjmp;
  ^

Test: treehugger
Change-Id: Iee6b0ea456bb2e92aea810ce45f171caabaa89d2
2024-01-23 22:06:19 +00:00

113 lines
4.2 KiB
C

/*
* Copyright (C) 2013 The Android Open Source Project
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#pragma once
/* https://github.com/android/ndk/issues/1422 */
#include <features.h>
#include <asm/unistd.h> /* For system call numbers. */
#define MAX_ERRNO 4095 /* For recognizing system call error returns. */
#define __bionic_asm_custom_entry(f)
#define __bionic_asm_custom_end(f)
#define __bionic_asm_function_type @function
#define __bionic_asm_custom_note_gnu_section()
#if defined(__aarch64__)
#include <private/bionic_asm_arm64.h>
#elif defined(__arm__)
#include <private/bionic_asm_arm.h>
#elif defined(__i386__)
#include <private/bionic_asm_x86.h>
#elif defined(__riscv)
#include <private/bionic_asm_riscv64.h>
#elif defined(__x86_64__)
#include <private/bionic_asm_x86_64.h>
#endif
// Starts a normal assembler routine.
#define ENTRY(__f) __ENTRY_WITH_BINDING(__f, .globl)
// Starts an assembler routine with hidden visibility.
#define ENTRY_PRIVATE(__f) \
__ENTRY_WITH_BINDING(__f, .globl); \
.hidden __f;
// Starts an assembler routine that's weak so native bridges can override it.
#define ENTRY_WEAK_FOR_NATIVE_BRIDGE(__f) __ENTRY_WITH_BINDING(__f, .weak)
// Starts an assembler routine with hidden visibility and no DWARF information.
// Only used for internal functions passed via sa_restorer.
// TODO: can't we just delete all those and let the kernel do its thing?
#define ENTRY_NO_DWARF_PRIVATE(__f) \
__ENTRY_NO_DWARF(__f, .globl); \
.hidden __f;
// (Implementation detail.)
#define __ENTRY_NO_DWARF(__f, __binding) \
.text; \
__binding __f; \
.balign __bionic_asm_align; \
.type __f, __bionic_asm_function_type; \
__f: \
__bionic_asm_custom_entry(__f);
// (Implementation detail.)
#define __ENTRY_WITH_BINDING(__f, __binding) \
__ENTRY_NO_DWARF(__f, __binding); \
.cfi_startproc;
// Ends a normal assembler routine.
#define END(__f) \
.cfi_endproc; \
END_NO_DWARF(__f)
// Ends an assembler routine with no DWARF information.
// Only used for internal functions passed via sa_restorer.
// TODO: can't we just delete all those and let the kernel do its thing?
#define END_NO_DWARF(__f) \
.size __f, .- __f; \
__bionic_asm_custom_end(__f)
// Creates an alias `alias` for the symbol `original`.
#define ALIAS_SYMBOL(alias, original) \
.globl alias; \
.equ alias, original
// Creates an alias `alias` for the symbol `original` that's weak so it can be
// separately overridden by native bridges.
#define ALIAS_SYMBOL_WEAK_FOR_NATIVE_BRIDGE(alias, original) \
.weak alias; \
.equ alias, original
// Adds a GNU property ELF note. Important on arm64 to declare PAC/BTI support.
#define NOTE_GNU_PROPERTY() __bionic_asm_custom_note_gnu_section()
// Gives local labels a more convenient and readable syntax.
#define L(__label) .L##__label