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//===-- assembly.h - compiler-rt assembler support macros -----------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
//
// This file defines macros for use in compiler-rt assembler source.
// This file is not part of the interface of this library.
//
//===----------------------------------------------------------------------===//
#ifndef COMPILERRT_ASSEMBLY_H
#define COMPILERRT_ASSEMBLY_H
#if defined(__linux__) && defined(__CET__)
#if __has_include(<cet.h>)
#include <cet.h>
#endif
#endif
#if defined(__APPLE__) && defined(__aarch64__)
#define SEPARATOR %%
#else
#define SEPARATOR ;
#endif
#if defined(__APPLE__)
#define HIDDEN(name) .private_extern name
#define LOCAL_LABEL(name) L_##name
// tell linker it can break up file at label boundaries
#define FILE_LEVEL_DIRECTIVE .subsections_via_symbols
#define SYMBOL_IS_FUNC(name)
#define CONST_SECTION .const
#define NO_EXEC_STACK_DIRECTIVE
#elif defined(__ELF__)
#define HIDDEN(name) .hidden name
#define LOCAL_LABEL(name) .L_##name
#define FILE_LEVEL_DIRECTIVE
#if defined(__arm__) || defined(__aarch64__)
#define SYMBOL_IS_FUNC(name) .type name,%function
#else
#define SYMBOL_IS_FUNC(name) .type name,@function
#endif
#define CONST_SECTION .section .rodata
#if defined(__GNU__) || defined(__FreeBSD__) || defined(__Fuchsia__) || \
defined(__linux__)
#define NO_EXEC_STACK_DIRECTIVE .section .note.GNU-stack,"",%progbits
#else
#define NO_EXEC_STACK_DIRECTIVE
#endif
#else // !__APPLE__ && !__ELF__
#define HIDDEN(name)
#define LOCAL_LABEL(name) .L ## name
#define FILE_LEVEL_DIRECTIVE
#define SYMBOL_IS_FUNC(name) \
.def name SEPARATOR \
.scl 2 SEPARATOR \
.type 32 SEPARATOR \
.endef
#define CONST_SECTION .section .rdata,"rd"
#define NO_EXEC_STACK_DIRECTIVE
#endif
#if defined(__arm__) || defined(__aarch64__)
#define FUNC_ALIGN \
.text SEPARATOR \
.balign 16 SEPARATOR
#else
#define FUNC_ALIGN
#endif
// BTI and PAC gnu property note
#define NT_GNU_PROPERTY_TYPE_0 5
#define GNU_PROPERTY_AARCH64_FEATURE_1_AND 0xc0000000
#define GNU_PROPERTY_AARCH64_FEATURE_1_BTI 1
#define GNU_PROPERTY_AARCH64_FEATURE_1_PAC 2
#if defined(__ARM_FEATURE_BTI_DEFAULT)
#define BTI_FLAG GNU_PROPERTY_AARCH64_FEATURE_1_BTI
#else
#define BTI_FLAG 0
#endif
#if __ARM_FEATURE_PAC_DEFAULT & 3
#define PAC_FLAG GNU_PROPERTY_AARCH64_FEATURE_1_PAC
#else
#define PAC_FLAG 0
#endif
#define GNU_PROPERTY(type, value) \
.pushsection .note.gnu.property, "a" SEPARATOR \
.p2align 3 SEPARATOR \
.word 4 SEPARATOR \
.word 16 SEPARATOR \
.word NT_GNU_PROPERTY_TYPE_0 SEPARATOR \
.asciz "GNU" SEPARATOR \
.word type SEPARATOR \
.word 4 SEPARATOR \
.word value SEPARATOR \
.word 0 SEPARATOR \
.popsection
#if BTI_FLAG != 0
#define BTI_C hint #34
#define BTI_J hint #36
#else
#define BTI_C
#define BTI_J
#endif
#if (BTI_FLAG | PAC_FLAG) != 0
#define GNU_PROPERTY_BTI_PAC \
GNU_PROPERTY(GNU_PROPERTY_AARCH64_FEATURE_1_AND, BTI_FLAG | PAC_FLAG)
#else
#define GNU_PROPERTY_BTI_PAC
#endif
#if defined(__clang__) || defined(__GCC_HAVE_DWARF2_CFI_ASM)
#define CFI_START .cfi_startproc
#define CFI_END .cfi_endproc
#else
#define CFI_START
#define CFI_END
#endif
#if defined(__arm__)
// Determine actual [ARM][THUMB[1][2]] ISA using compiler predefined macros:
// - for '-mthumb -march=armv6' compiler defines '__thumb__'
// - for '-mthumb -march=armv7' compiler defines '__thumb__' and '__thumb2__'
#if defined(__thumb2__) || defined(__thumb__)
#define DEFINE_CODE_STATE .thumb SEPARATOR
#define DECLARE_FUNC_ENCODING .thumb_func SEPARATOR
#if defined(__thumb2__)
#define USE_THUMB_2
#define IT(cond) it cond
#define ITT(cond) itt cond
#define ITE(cond) ite cond
#else
#define USE_THUMB_1
#define IT(cond)
#define ITT(cond)
#define ITE(cond)
#endif // defined(__thumb__2)
#else // !defined(__thumb2__) && !defined(__thumb__)
#define DEFINE_CODE_STATE .arm SEPARATOR
#define DECLARE_FUNC_ENCODING
#define IT(cond)
#define ITT(cond)
#define ITE(cond)
#endif
#if defined(USE_THUMB_1) && defined(USE_THUMB_2)
#error "USE_THUMB_1 and USE_THUMB_2 can't be defined together."
#endif
#if defined(__ARM_ARCH_4T__) || __ARM_ARCH >= 5
#define ARM_HAS_BX
#endif
#if !defined(__ARM_FEATURE_CLZ) && !defined(USE_THUMB_1) && \
(__ARM_ARCH >= 6 || (__ARM_ARCH == 5 && !defined(__ARM_ARCH_5__)))
#define __ARM_FEATURE_CLZ
#endif
#ifdef ARM_HAS_BX
#define JMP(r) bx r
#define JMPc(r, c) bx##c r
#else
#define JMP(r) mov pc, r
#define JMPc(r, c) mov##c pc, r
#endif
// pop {pc} can't switch Thumb mode on ARMv4T
#if __ARM_ARCH >= 5
#define POP_PC() pop {pc}
#else
#define POP_PC() \
pop {ip}; \
JMP(ip)
#endif
#if defined(USE_THUMB_2)
#define WIDE(op) op.w
#else
#define WIDE(op) op
#endif
#else // !defined(__arm)
#define DECLARE_FUNC_ENCODING
#define DEFINE_CODE_STATE
#endif
#define GLUE2_(a, b) a##b
#define GLUE(a, b) GLUE2_(a, b)
#define GLUE2(a, b) GLUE2_(a, b)
#define GLUE3_(a, b, c) a##b##c
#define GLUE3(a, b, c) GLUE3_(a, b, c)
#define GLUE4_(a, b, c, d) a##b##c##d
#define GLUE4(a, b, c, d) GLUE4_(a, b, c, d)
#define SYMBOL_NAME(name) GLUE(__USER_LABEL_PREFIX__, name)
#ifdef VISIBILITY_HIDDEN
#define DECLARE_SYMBOL_VISIBILITY(name) \
HIDDEN(SYMBOL_NAME(name)) SEPARATOR
#define DECLARE_SYMBOL_VISIBILITY_UNMANGLED(name) \
HIDDEN(name) SEPARATOR
#else
#define DECLARE_SYMBOL_VISIBILITY(name)
#define DECLARE_SYMBOL_VISIBILITY_UNMANGLED(name)
#endif
#define DEFINE_COMPILERRT_FUNCTION(name) \
DEFINE_CODE_STATE \
FILE_LEVEL_DIRECTIVE SEPARATOR \
.globl SYMBOL_NAME(name) SEPARATOR \
SYMBOL_IS_FUNC(SYMBOL_NAME(name)) SEPARATOR \
DECLARE_SYMBOL_VISIBILITY(name) \
DECLARE_FUNC_ENCODING \
SYMBOL_NAME(name):
#define DEFINE_COMPILERRT_THUMB_FUNCTION(name) \
DEFINE_CODE_STATE \
FILE_LEVEL_DIRECTIVE SEPARATOR \
.globl SYMBOL_NAME(name) SEPARATOR \
SYMBOL_IS_FUNC(SYMBOL_NAME(name)) SEPARATOR \
DECLARE_SYMBOL_VISIBILITY(name) SEPARATOR \
.thumb_func SEPARATOR \
SYMBOL_NAME(name):
#define DEFINE_COMPILERRT_PRIVATE_FUNCTION(name) \
DEFINE_CODE_STATE \
FILE_LEVEL_DIRECTIVE SEPARATOR \
.globl SYMBOL_NAME(name) SEPARATOR \
SYMBOL_IS_FUNC(SYMBOL_NAME(name)) SEPARATOR \
HIDDEN(SYMBOL_NAME(name)) SEPARATOR \
DECLARE_FUNC_ENCODING \
SYMBOL_NAME(name):
#define DEFINE_COMPILERRT_PRIVATE_FUNCTION_UNMANGLED(name) \
DEFINE_CODE_STATE \
.globl name SEPARATOR \
SYMBOL_IS_FUNC(name) SEPARATOR \
HIDDEN(name) SEPARATOR \
DECLARE_FUNC_ENCODING \
name:
#define DEFINE_COMPILERRT_OUTLINE_FUNCTION_UNMANGLED(name) \
DEFINE_CODE_STATE \
FUNC_ALIGN \
.globl name SEPARATOR \
SYMBOL_IS_FUNC(name) SEPARATOR \
DECLARE_SYMBOL_VISIBILITY_UNMANGLED(name) SEPARATOR \
DECLARE_FUNC_ENCODING \
name: \
SEPARATOR CFI_START \
SEPARATOR BTI_C
#define DEFINE_COMPILERRT_FUNCTION_ALIAS(name, target) \
.globl SYMBOL_NAME(name) SEPARATOR \
SYMBOL_IS_FUNC(SYMBOL_NAME(name)) SEPARATOR \
DECLARE_SYMBOL_VISIBILITY(name) SEPARATOR \
.set SYMBOL_NAME(name), SYMBOL_NAME(target) SEPARATOR
#if defined(__ARM_EABI__)
#define DEFINE_AEABI_FUNCTION_ALIAS(aeabi_name, name) \
DEFINE_COMPILERRT_FUNCTION_ALIAS(aeabi_name, name)
#else
#define DEFINE_AEABI_FUNCTION_ALIAS(aeabi_name, name)
#endif
#ifdef __ELF__
#define END_COMPILERRT_FUNCTION(name) \
.size SYMBOL_NAME(name), . - SYMBOL_NAME(name)
#define END_COMPILERRT_OUTLINE_FUNCTION(name) \
CFI_END SEPARATOR \
.size SYMBOL_NAME(name), . - SYMBOL_NAME(name)
#else
#define END_COMPILERRT_FUNCTION(name)
#define END_COMPILERRT_OUTLINE_FUNCTION(name) \
CFI_END
#endif
#endif // COMPILERRT_ASSEMBLY_H