libsanitizer/builtins/assembly.h

   1 //===-- assembly.h - compiler-rt assembler support macros -----------------===//
   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 // This file defines macros for use in compiler-rt assembler source.
  10 // This file is not part of the interface of this library.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #ifndef COMPILERRT_ASSEMBLY_H
  15 #define COMPILERRT_ASSEMBLY_H
  16
  17 #if defined(__POWERPC__) || defined(__powerpc__) || defined(__ppc__)
  18 #define SEPARATOR @
  19 #else
  20 #define SEPARATOR ;
  21 #endif
  22
  23 #if defined(__APPLE__)
  24 #define HIDDEN(name) .private_extern name
  25 #define LOCAL_LABEL(name) L_##name
  26 // tell linker it can break up file at label boundaries
  27 #define FILE_LEVEL_DIRECTIVE .subsections_via_symbols
  28 #define SYMBOL_IS_FUNC(name)
  29 #define CONST_SECTION .const
  30
  31 #define NO_EXEC_STACK_DIRECTIVE
  32
  33 #elif defined(__ELF__)
  34
  35 #define HIDDEN(name) .hidden name
  36 #define LOCAL_LABEL(name) .L_##name
  37 #define FILE_LEVEL_DIRECTIVE
  38 #if defined(__arm__)
  39 #define SYMBOL_IS_FUNC(name) .type name,%function
  40 #else
  41 #define SYMBOL_IS_FUNC(name) .type name,@function
  42 #endif
  43 #define CONST_SECTION .section .rodata
  44
  45 #if defined(__GNU__) || defined(__FreeBSD__) || defined(__Fuchsia__) || \
  46     defined(__linux__)
  47 #define NO_EXEC_STACK_DIRECTIVE .section .note.GNU-stack,"",%progbits
  48 #else
  49 #define NO_EXEC_STACK_DIRECTIVE
  50 #endif
  51
  52 #else // !__APPLE__ && !__ELF__
  53
  54 #define HIDDEN(name)
  55 #define LOCAL_LABEL(name) .L ## name
  56 #define FILE_LEVEL_DIRECTIVE
  57 #define SYMBOL_IS_FUNC(name)                                                   \
  58   .def name SEPARATOR                                                          \
  59     .scl 2 SEPARATOR                                                           \
  60     .type 32 SEPARATOR                                                         \
  61   .endef
  62 #define CONST_SECTION .section .rdata,"rd"
  63
  64 #define NO_EXEC_STACK_DIRECTIVE
  65
  66 #endif
  67
  68 #if defined(__arm__)
  69
  70 // Determine actual [ARM][THUMB[1][2]] ISA using compiler predefined macros:
  71 // - for '-mthumb -march=armv6' compiler defines '__thumb__'
  72 // - for '-mthumb -march=armv7' compiler defines '__thumb__' and '__thumb2__'
  73 #if defined(__thumb2__) || defined(__thumb__)
  74 #define DEFINE_CODE_STATE .thumb SEPARATOR
  75 #define DECLARE_FUNC_ENCODING    .thumb_func SEPARATOR
  76 #if defined(__thumb2__)
  77 #define USE_THUMB_2
  78 #define IT(cond)  it cond
  79 #define ITT(cond) itt cond
  80 #define ITE(cond) ite cond
  81 #else
  82 #define USE_THUMB_1
  83 #define IT(cond)
  84 #define ITT(cond)
  85 #define ITE(cond)
  86 #endif // defined(__thumb__2)
  87 #else // !defined(__thumb2__) && !defined(__thumb__)
  88 #define DEFINE_CODE_STATE .arm SEPARATOR
  89 #define DECLARE_FUNC_ENCODING
  90 #define IT(cond)
  91 #define ITT(cond)
  92 #define ITE(cond)
  93 #endif
  94
  95 #if defined(USE_THUMB_1) && defined(USE_THUMB_2)
  96 #error "USE_THUMB_1 and USE_THUMB_2 can't be defined together."
  97 #endif
  98
  99 #if defined(__ARM_ARCH_4T__) || __ARM_ARCH >= 5
 100 #define ARM_HAS_BX
 101 #endif
 102 #if !defined(__ARM_FEATURE_CLZ) && !defined(USE_THUMB_1) &&  \
 103     (__ARM_ARCH >= 6 || (__ARM_ARCH == 5 && !defined(__ARM_ARCH_5__)))
 104 #define __ARM_FEATURE_CLZ
 105 #endif
 106
 107 #ifdef ARM_HAS_BX
 108 #define JMP(r) bx r
 109 #define JMPc(r, c) bx##c r
 110 #else
 111 #define JMP(r) mov pc, r
 112 #define JMPc(r, c) mov##c pc, r
 113 #endif
 114
 115 // pop {pc} can't switch Thumb mode on ARMv4T
 116 #if __ARM_ARCH >= 5
 117 #define POP_PC() pop {pc}
 118 #else
 119 #define POP_PC()                                                               \
 120   pop {ip};                                                                    \
 121   JMP(ip)
 122 #endif
 123
 124 #if defined(USE_THUMB_2)
 125 #define WIDE(op) op.w
 126 #else
 127 #define WIDE(op) op
 128 #endif
 129 #else // !defined(__arm)
 130 #define DECLARE_FUNC_ENCODING
 131 #define DEFINE_CODE_STATE
 132 #endif
 133
 134 #define GLUE2(a, b) a##b
 135 #define GLUE(a, b) GLUE2(a, b)
 136 #define SYMBOL_NAME(name) GLUE(__USER_LABEL_PREFIX__, name)
 137
 138 #ifdef VISIBILITY_HIDDEN
 139 #define DECLARE_SYMBOL_VISIBILITY(name)                                        \
 140   HIDDEN(SYMBOL_NAME(name)) SEPARATOR
 141 #else
 142 #define DECLARE_SYMBOL_VISIBILITY(name)
 143 #endif
 144
 145 #define DEFINE_COMPILERRT_FUNCTION(name)                                       \
 146   DEFINE_CODE_STATE                                                            \
 147   FILE_LEVEL_DIRECTIVE SEPARATOR                                               \
 148   .globl SYMBOL_NAME(name) SEPARATOR                                           \
 149   SYMBOL_IS_FUNC(SYMBOL_NAME(name)) SEPARATOR                                  \
 150   DECLARE_SYMBOL_VISIBILITY(name)                                              \
 151   DECLARE_FUNC_ENCODING                                                        \
 152   SYMBOL_NAME(name):
 153
 154 #define DEFINE_COMPILERRT_THUMB_FUNCTION(name)                                 \
 155   DEFINE_CODE_STATE                                                            \
 156   FILE_LEVEL_DIRECTIVE SEPARATOR                                               \
 157   .globl SYMBOL_NAME(name) SEPARATOR                                           \
 158   SYMBOL_IS_FUNC(SYMBOL_NAME(name)) SEPARATOR                                  \
 159   DECLARE_SYMBOL_VISIBILITY(name) SEPARATOR                                    \
 160   .thumb_func SEPARATOR                                                        \
 161   SYMBOL_NAME(name):
 162
 163 #define DEFINE_COMPILERRT_PRIVATE_FUNCTION(name)                               \
 164   DEFINE_CODE_STATE                                                            \
 165   FILE_LEVEL_DIRECTIVE SEPARATOR                                               \
 166   .globl SYMBOL_NAME(name) SEPARATOR                                           \
 167   SYMBOL_IS_FUNC(SYMBOL_NAME(name)) SEPARATOR                                  \
 168   HIDDEN(SYMBOL_NAME(name)) SEPARATOR                                          \
 169   DECLARE_FUNC_ENCODING                                                        \
 170   SYMBOL_NAME(name):
 171
 172 #define DEFINE_COMPILERRT_PRIVATE_FUNCTION_UNMANGLED(name)                     \
 173   DEFINE_CODE_STATE                                                            \
 174   .globl name SEPARATOR                                                        \
 175   SYMBOL_IS_FUNC(name) SEPARATOR                                               \
 176   HIDDEN(name) SEPARATOR                                                       \
 177   DECLARE_FUNC_ENCODING                                                        \
 178   name:
 179
 180 #define DEFINE_COMPILERRT_FUNCTION_ALIAS(name, target)                         \
 181   .globl SYMBOL_NAME(name) SEPARATOR                                           \
 182   SYMBOL_IS_FUNC(SYMBOL_NAME(name)) SEPARATOR                                  \
 183   DECLARE_SYMBOL_VISIBILITY(SYMBOL_NAME(name)) SEPARATOR                       \
 184   .set SYMBOL_NAME(name), SYMBOL_NAME(target) SEPARATOR
 185
 186 #if defined(__ARM_EABI__)
 187 #define DEFINE_AEABI_FUNCTION_ALIAS(aeabi_name, name)                          \
 188   DEFINE_COMPILERRT_FUNCTION_ALIAS(aeabi_name, name)
 189 #else
 190 #define DEFINE_AEABI_FUNCTION_ALIAS(aeabi_name, name)
 191 #endif
 192
 193 #ifdef __ELF__
 194 #define END_COMPILERRT_FUNCTION(name)                                          \
 195   .size SYMBOL_NAME(name), . - SYMBOL_NAME(name)
 196 #else
 197 #define END_COMPILERRT_FUNCTION(name)
 198 #endif
 199
 200 #endif // COMPILERRT_ASSEMBLY_H