libunwind/src/assembly.h

   1 /* ===-- assembly.h - libUnwind 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 libUnwind assembler source.
  10  * This file is not part of the interface of this library.
  11  *
  12  * ===----------------------------------------------------------------------===
  13  */
  14
  15 #ifndef UNWIND_ASSEMBLY_H
  16 #define UNWIND_ASSEMBLY_H
  17
  18 #if defined(__linux__) && defined(__CET__)
  19 #include <cet.h>
  20 #define _LIBUNWIND_CET_ENDBR _CET_ENDBR
  21 #else
  22 #define _LIBUNWIND_CET_ENDBR
  23 #endif
  24
  25 #if defined(__powerpc64__)
  26 #define SEPARATOR ;
  27 #define PPC64_OFFS_SRR0   0
  28 #define PPC64_OFFS_CR     272
  29 #define PPC64_OFFS_XER    280
  30 #define PPC64_OFFS_LR     288
  31 #define PPC64_OFFS_CTR    296
  32 #define PPC64_OFFS_VRSAVE 304
  33 #define PPC64_OFFS_FP     312
  34 #define PPC64_OFFS_V      824
  35 #elif defined(__APPLE__) && defined(__aarch64__)
  36 #define SEPARATOR %%
  37 #elif defined(__riscv)
  38 # define RISCV_ISIZE (__riscv_xlen / 8)
  39 # define RISCV_FOFFSET (RISCV_ISIZE * 32)
  40 # if defined(__riscv_flen)
  41 #  define RISCV_FSIZE (__riscv_flen / 8)
  42 # endif
  43
  44 # if __riscv_xlen == 64
  45 #  define ILOAD ld
  46 #  define ISTORE sd
  47 # elif __riscv_xlen == 32
  48 #  define ILOAD lw
  49 #  define ISTORE sw
  50 # else
  51 #  error "Unsupported __riscv_xlen"
  52 # endif
  53
  54 # if defined(__riscv_flen)
  55 #  if __riscv_flen == 64
  56 #   define FLOAD fld
  57 #   define FSTORE fsd
  58 #  elif __riscv_flen == 32
  59 #   define FLOAD flw
  60 #   define FSTORE fsw
  61 #  else
  62 #   error "Unsupported __riscv_flen"
  63 #  endif
  64 # endif
  65 # define SEPARATOR ;
  66 #else
  67 #define SEPARATOR ;
  68 #endif
  69
  70 #if defined(__powerpc64__) && (!defined(_CALL_ELF) || _CALL_ELF == 1) &&       \
  71     !defined(_AIX)
  72 #define PPC64_OPD1 .section .opd,"aw",@progbits SEPARATOR
  73 #define PPC64_OPD2 SEPARATOR \
  74   .p2align 3 SEPARATOR \
  75   .quad .Lfunc_begin0 SEPARATOR \
  76   .quad .TOC.@tocbase SEPARATOR \
  77   .quad 0 SEPARATOR \
  78   .text SEPARATOR \
  79 .Lfunc_begin0:
  80 #else
  81 #define PPC64_OPD1
  82 #define PPC64_OPD2
  83 #endif
  84
  85 #if defined(__aarch64__)
  86 #if defined(__ARM_FEATURE_GCS_DEFAULT) && defined(__ARM_FEATURE_BTI_DEFAULT)
  87 // Set BTI, PAC, and GCS gnu property bits
  88 #define GNU_PROPERTY 7
  89 // We indirectly branch to __libunwind_Registers_arm64_jumpto from
  90 // __unw_phase2_resume, so we need to use bti jc.
  91 #define AARCH64_BTI bti jc
  92 #elif defined(__ARM_FEATURE_GCS_DEFAULT)
  93 // Set GCS gnu property bit
  94 #define GNU_PROPERTY 4
  95 #elif defined(__ARM_FEATURE_BTI_DEFAULT)
  96 // Set BTI and PAC gnu property bits
  97 #define GNU_PROPERTY 3
  98 #define AARCH64_BTI bti c
  99 #endif
 100 #ifdef GNU_PROPERTY
 101   .pushsection ".note.gnu.property", "a" SEPARATOR                             \
 102   .balign 8 SEPARATOR                                                          \
 103   .long 4 SEPARATOR                                                            \
 104   .long 0x10 SEPARATOR                                                         \
 105   .long 0x5 SEPARATOR                                                          \
 106   .asciz "GNU" SEPARATOR                                                       \
 107   .long 0xc0000000 SEPARATOR /* GNU_PROPERTY_AARCH64_FEATURE_1_AND */          \
 108   .long 4 SEPARATOR                                                            \
 109   .long GNU_PROPERTY SEPARATOR                                                 \
 110   .long 0 SEPARATOR                                                            \
 111   .popsection SEPARATOR
 112 #endif
 113 #endif
 114 #if !defined(AARCH64_BTI)
 115 #define AARCH64_BTI
 116 #endif
 117
 118 #if !defined(__aarch64__)
 119 #ifdef __ARM_FEATURE_PAC_DEFAULT
 120   .eabi_attribute Tag_PAC_extension, 2
 121   .eabi_attribute Tag_PACRET_use, 1
 122 #endif
 123 #ifdef __ARM_FEATURE_BTI_DEFAULT
 124   .eabi_attribute Tag_BTI_extension, 1
 125   .eabi_attribute Tag_BTI_use, 1
 126 #endif
 127 #endif
 128
 129 #define GLUE2(a, b) a ## b
 130 #define GLUE(a, b) GLUE2(a, b)
 131 #define SYMBOL_NAME(name) GLUE(__USER_LABEL_PREFIX__, name)
 132
 133 #if defined(__APPLE__)
 134
 135 #define SYMBOL_IS_FUNC(name)
 136 #define HIDDEN_SYMBOL(name) .private_extern name
 137 #if defined(_LIBUNWIND_HIDE_SYMBOLS)
 138 #define EXPORT_SYMBOL(name) HIDDEN_SYMBOL(name)
 139 #else
 140 #define EXPORT_SYMBOL(name)
 141 #endif
 142 #define WEAK_ALIAS(name, aliasname)                                            \
 143   .globl SYMBOL_NAME(aliasname) SEPARATOR                                      \
 144   EXPORT_SYMBOL(SYMBOL_NAME(aliasname)) SEPARATOR                              \
 145   SYMBOL_NAME(aliasname) = SYMBOL_NAME(name)
 146
 147 #define NO_EXEC_STACK_DIRECTIVE
 148
 149 #elif defined(__ELF__)
 150
 151 #if defined(__arm__)
 152 #define SYMBOL_IS_FUNC(name) .type name,%function
 153 #else
 154 #define SYMBOL_IS_FUNC(name) .type name,@function
 155 #endif
 156 #define HIDDEN_SYMBOL(name) .hidden name
 157 #if defined(_LIBUNWIND_HIDE_SYMBOLS)
 158 #define EXPORT_SYMBOL(name) HIDDEN_SYMBOL(name)
 159 #else
 160 #define EXPORT_SYMBOL(name)
 161 #endif
 162 #define WEAK_SYMBOL(name) .weak name
 163
 164 #if defined(__hexagon__)
 165 #define WEAK_ALIAS(name, aliasname)                                            \
 166   EXPORT_SYMBOL(SYMBOL_NAME(aliasname)) SEPARATOR                              \
 167   WEAK_SYMBOL(SYMBOL_NAME(aliasname)) SEPARATOR                                \
 168   .equiv SYMBOL_NAME(aliasname), SYMBOL_NAME(name)
 169 #else
 170 #define WEAK_ALIAS(name, aliasname)                                            \
 171   EXPORT_SYMBOL(SYMBOL_NAME(aliasname)) SEPARATOR                              \
 172   WEAK_SYMBOL(SYMBOL_NAME(aliasname)) SEPARATOR                                \
 173   SYMBOL_NAME(aliasname) = SYMBOL_NAME(name)
 174 #endif
 175
 176 #if defined(__GNU__) || defined(__FreeBSD__) || defined(__Fuchsia__) || \
 177     defined(__linux__)
 178 #define NO_EXEC_STACK_DIRECTIVE .section .note.GNU-stack,"",%progbits
 179 #else
 180 #define NO_EXEC_STACK_DIRECTIVE
 181 #endif
 182
 183 #elif defined(_WIN32)
 184
 185 #define SYMBOL_IS_FUNC(name)                                                   \
 186   .def name SEPARATOR                                                          \
 187     .scl 2 SEPARATOR                                                           \
 188     .type 32 SEPARATOR                                                         \
 189   .endef
 190 #define EXPORT_SYMBOL2(name)                                                   \
 191   .section .drectve,"yn" SEPARATOR                                             \
 192   .ascii "-export:", #name, "\0" SEPARATOR                                     \
 193   .text
 194 #if defined(_LIBUNWIND_HIDE_SYMBOLS)
 195 #define EXPORT_SYMBOL(name)
 196 #else
 197 #define EXPORT_SYMBOL(name) EXPORT_SYMBOL2(name)
 198 #endif
 199 #define HIDDEN_SYMBOL(name)
 200
 201 #if defined(__MINGW32__)
 202 #define WEAK_ALIAS(name, aliasname)                                            \
 203   .globl SYMBOL_NAME(aliasname) SEPARATOR                                      \
 204   EXPORT_SYMBOL(aliasname) SEPARATOR                                           \
 205   SYMBOL_NAME(aliasname) = SYMBOL_NAME(name)
 206 #else
 207 #define WEAK_ALIAS3(name, aliasname)                                           \
 208   .section .drectve,"yn" SEPARATOR                                             \
 209   .ascii "-alternatename:", #aliasname, "=", #name, "\0" SEPARATOR             \
 210   .text
 211 #define WEAK_ALIAS2(name, aliasname)                                           \
 212   WEAK_ALIAS3(name, aliasname)
 213 #define WEAK_ALIAS(name, aliasname)                                            \
 214   EXPORT_SYMBOL(SYMBOL_NAME(aliasname)) SEPARATOR                              \
 215   WEAK_ALIAS2(SYMBOL_NAME(name), SYMBOL_NAME(aliasname))
 216 #endif
 217
 218 #define NO_EXEC_STACK_DIRECTIVE
 219
 220 #elif defined(__sparc__)
 221
 222 #elif defined(_AIX)
 223
 224 #if defined(__powerpc64__)
 225 #define VBYTE_LEN 8
 226 #define CSECT_ALIGN 3
 227 #else
 228 #define VBYTE_LEN 4
 229 #define CSECT_ALIGN 2
 230 #endif
 231
 232 // clang-format off
 233 #define DEFINE_LIBUNWIND_FUNCTION_AND_WEAK_ALIAS(name, aliasname)              \
 234   .csect .text[PR], 2 SEPARATOR                                                \
 235   .csect .name[PR], 2 SEPARATOR                                                \
 236   .globl name[DS] SEPARATOR                                                    \
 237   .globl .name[PR] SEPARATOR                                                   \
 238   .align 4 SEPARATOR                                                           \
 239   .csect name[DS], CSECT_ALIGN SEPARATOR                                       \
 240 aliasname:                                                                     \
 241   .vbyte VBYTE_LEN, .name[PR] SEPARATOR                                        \
 242   .vbyte VBYTE_LEN, TOC[TC0] SEPARATOR                                         \
 243   .vbyte VBYTE_LEN, 0 SEPARATOR                                                \
 244   .weak  aliasname SEPARATOR                                                   \
 245   .weak  .aliasname SEPARATOR                                                  \
 246   .csect .name[PR], 2 SEPARATOR                                                \
 247 .aliasname:                                                                    \
 248
 249 #define WEAK_ALIAS(name, aliasname)
 250 #define NO_EXEC_STACK_DIRECTIVE
 251
 252 // clang-format on
 253 #else
 254
 255 #error Unsupported target
 256
 257 #endif
 258
 259 #if defined(_AIX)
 260   // clang-format off
 261 #define DEFINE_LIBUNWIND_FUNCTION(name)                                        \
 262   .globl name[DS] SEPARATOR                                                    \
 263   .globl .name SEPARATOR                                                       \
 264   .align 4 SEPARATOR                                                           \
 265   .csect name[DS], CSECT_ALIGN SEPARATOR                                       \
 266   .vbyte VBYTE_LEN, .name SEPARATOR                                            \
 267   .vbyte VBYTE_LEN, TOC[TC0] SEPARATOR                                         \
 268   .vbyte VBYTE_LEN, 0 SEPARATOR                                                \
 269   .csect .text[PR], 2 SEPARATOR                                                \
 270 .name:
 271   // clang-format on
 272 #else
 273 #define DEFINE_LIBUNWIND_FUNCTION(name)                                        \
 274   .globl SYMBOL_NAME(name) SEPARATOR                                           \
 275   HIDDEN_SYMBOL(SYMBOL_NAME(name)) SEPARATOR                                   \
 276   SYMBOL_IS_FUNC(SYMBOL_NAME(name)) SEPARATOR                                  \
 277   PPC64_OPD1                                                                   \
 278   SYMBOL_NAME(name):                                                           \
 279   PPC64_OPD2                                                                   \
 280   AARCH64_BTI
 281 #endif
 282
 283 #if defined(__arm__)
 284 #if !defined(__ARM_ARCH)
 285 #define __ARM_ARCH 4
 286 #endif
 287
 288 #if defined(__ARM_ARCH_4T__) || __ARM_ARCH >= 5
 289 #define ARM_HAS_BX
 290 #endif
 291
 292 #ifdef ARM_HAS_BX
 293 #define JMP(r) bx r
 294 #else
 295 #define JMP(r) mov pc, r
 296 #endif
 297 #endif /* __arm__ */
 298
 299 #if defined(__powerpc__)
 300 #define PPC_LEFT_SHIFT(index) << (index)
 301 #endif
 302
 303 #endif /* UNWIND_ASSEMBLY_H */