aom_ports/x86_abi_support.asm

   1 ;
   2 ; Copyright (c) 2016, Alliance for Open Media. All rights reserved
   3 ;
   4 ; This source code is subject to the terms of the BSD 2 Clause License and
   5 ; the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
   6 ; was not distributed with this source code in the LICENSE file, you can
   7 ; obtain it at www.aomedia.org/license/software. If the Alliance for Open
   8 ; Media Patent License 1.0 was not distributed with this source code in the
   9 ; PATENTS file, you can obtain it at www.aomedia.org/license/patent.
  10 ;
  11
  12 ;
  13
  14
  15 %include "config/aom_config.asm"
  16
  17 ; 32/64 bit compatibility macros
  18 ;
  19 ; In general, we make the source use 64 bit syntax, then twiddle with it using
  20 ; the preprocessor to get the 32 bit syntax on 32 bit platforms.
  21 ;
  22 %ifidn __OUTPUT_FORMAT__,elf32
  23 %define ABI_IS_32BIT 1
  24 %elifidn __OUTPUT_FORMAT__,macho32
  25 %define ABI_IS_32BIT 1
  26 %elifidn __OUTPUT_FORMAT__,win32
  27 %define ABI_IS_32BIT 1
  28 %elifidn __OUTPUT_FORMAT__,aout
  29 %define ABI_IS_32BIT 1
  30 %else
  31 %define ABI_IS_32BIT 0
  32 %endif
  33
  34 %if ABI_IS_32BIT
  35 %define rax eax
  36 %define rbx ebx
  37 %define rcx ecx
  38 %define rdx edx
  39 %define rsi esi
  40 %define rdi edi
  41 %define rsp esp
  42 %define rbp ebp
  43 %define movsxd mov
  44 %macro movq 2
  45   %ifidn %1,eax
  46     movd %1,%2
  47   %elifidn %2,eax
  48     movd %1,%2
  49   %elifidn %1,ebx
  50     movd %1,%2
  51   %elifidn %2,ebx
  52     movd %1,%2
  53   %elifidn %1,ecx
  54     movd %1,%2
  55   %elifidn %2,ecx
  56     movd %1,%2
  57   %elifidn %1,edx
  58     movd %1,%2
  59   %elifidn %2,edx
  60     movd %1,%2
  61   %elifidn %1,esi
  62     movd %1,%2
  63   %elifidn %2,esi
  64     movd %1,%2
  65   %elifidn %1,edi
  66     movd %1,%2
  67   %elifidn %2,edi
  68     movd %1,%2
  69   %elifidn %1,esp
  70     movd %1,%2
  71   %elifidn %2,esp
  72     movd %1,%2
  73   %elifidn %1,ebp
  74     movd %1,%2
  75   %elifidn %2,ebp
  76     movd %1,%2
  77   %else
  78     movq %1,%2
  79   %endif
  80 %endmacro
  81 %endif
  82
  83
  84 ; LIBAOM_YASM_WIN64
  85 ; Set LIBAOM_YASM_WIN64 if output is Windows 64bit so the code will work if x64
  86 ; or win64 is defined on the Yasm command line.
  87 %ifidn __OUTPUT_FORMAT__,win64
  88 %define LIBAOM_YASM_WIN64 1
  89 %elifidn __OUTPUT_FORMAT__,x64
  90 %define LIBAOM_YASM_WIN64 1
  91 %else
  92 %define LIBAOM_YASM_WIN64 0
  93 %endif
  94
  95 ; Declare groups of platforms
  96 %ifidn   __OUTPUT_FORMAT__,elf32
  97   %define LIBAOM_ELF 1
  98 %elifidn   __OUTPUT_FORMAT__,elfx32
  99   %define LIBAOM_ELF 1
 100 %elifidn   __OUTPUT_FORMAT__,elf64
 101   %define LIBAOM_ELF 1
 102 %else
 103   %define LIBAOM_ELF 0
 104 %endif
 105
 106 %ifidn __OUTPUT_FORMAT__,macho32
 107   %define LIBAOM_MACHO 1
 108 %elifidn __OUTPUT_FORMAT__,macho64
 109   %define LIBAOM_MACHO 1
 110 %else
 111   %define LIBAOM_MACHO 0
 112 %endif
 113
 114 ; sym()
 115 ; Return the proper symbol name for the target ABI.
 116 ;
 117 ; Certain ABIs, notably MS COFF and Darwin MACH-O, require that symbols
 118 ; with C linkage be prefixed with an underscore.
 119 ;
 120 %if LIBAOM_ELF || LIBAOM_YASM_WIN64
 121   %define sym(x) x
 122 %else
 123   ; Mach-O / COFF
 124   %define sym(x) _ %+ x
 125 %endif
 126
 127 ; globalsym()
 128 ; Return a global declaration with the proper decoration for the target ABI.
 129 ;
 130 ; When CHROMIUM is defined, include attributes to hide the symbol from the
 131 ; global namespace.
 132 ;
 133 ; Chromium doesn't like exported global symbols due to symbol clashing with
 134 ; plugins among other things.
 135 ;
 136 ; Requires Chromium's patched copy of yasm:
 137 ;   http://src.chromium.org/viewvc/chrome?view=rev&revision=73761
 138 ;   http://www.tortall.net/projects/yasm/ticket/236
 139 ; or nasm > 2.14.
 140 ;
 141 %ifdef CHROMIUM
 142   %ifdef __NASM_VER__
 143     %if __NASM_VERSION_ID__ < 0x020e0000 ; 2.14
 144       ; nasm < 2.14 does not support :private_extern directive
 145       %fatal Must use nasm 2.14 or newer
 146     %endif
 147   %endif
 148
 149   %if LIBAOM_ELF
 150     %define globalsym(x) global sym(x) %+ :function hidden
 151   %elif LIBAOM_MACHO
 152     %define globalsym(x) global sym(x) %+ :private_extern
 153   %else
 154     ; COFF / PE32+
 155     %define globalsym(x) global sym(x)
 156   %endif
 157 %else
 158   %define globalsym(x) global sym(x)
 159 %endif
 160
 161 ; arg()
 162 ; Return the address specification of the given argument
 163 ;
 164 %if ABI_IS_32BIT
 165   %define arg(x) [ebp+8+4*x]
 166 %else
 167   ; 64 bit ABI passes arguments in registers. This is a workaround to get up
 168   ; and running quickly. Relies on SHADOW_ARGS_TO_STACK
 169   %if LIBAOM_YASM_WIN64
 170     %define arg(x) [rbp+16+8*x]
 171   %else
 172     %define arg(x) [rbp-8-8*x]
 173   %endif
 174 %endif
 175
 176 ; REG_SZ_BYTES, REG_SZ_BITS
 177 ; Size of a register
 178 %if ABI_IS_32BIT
 179 %define REG_SZ_BYTES 4
 180 %define REG_SZ_BITS  32
 181 %else
 182 %define REG_SZ_BYTES 8
 183 %define REG_SZ_BITS  64
 184 %endif
 185
 186
 187 ; ALIGN_STACK <alignment> <register>
 188 ; This macro aligns the stack to the given alignment (in bytes). The stack
 189 ; is left such that the previous value of the stack pointer is the first
 190 ; argument on the stack (ie, the inverse of this macro is 'pop rsp.')
 191 ; This macro uses one temporary register, which is not preserved, and thus
 192 ; must be specified as an argument.
 193 %macro ALIGN_STACK 2
 194     mov         %2, rsp
 195     and         rsp, -%1
 196     lea         rsp, [rsp - (%1 - REG_SZ_BYTES)]
 197     push        %2
 198 %endmacro
 199
 200
 201 ;
 202 ; The Microsoft assembler tries to impose a certain amount of type safety in
 203 ; its register usage. YASM doesn't recognize these directives, so we just
 204 ; %define them away to maintain as much compatibility as possible with the
 205 ; original inline assembler we're porting from.
 206 ;
 207 %idefine PTR
 208 %idefine XMMWORD
 209 %idefine MMWORD
 210
 211 ; PIC macros
 212 ;
 213 %if ABI_IS_32BIT
 214   %if CONFIG_PIC=1
 215   %ifidn __OUTPUT_FORMAT__,elf32
 216     %define WRT_PLT wrt ..plt
 217     %macro GET_GOT 1
 218       extern _GLOBAL_OFFSET_TABLE_
 219       push %1
 220       call %%get_got
 221       %%sub_offset:
 222       jmp %%exitGG
 223       %%get_got:
 224       mov %1, [esp]
 225       add %1, _GLOBAL_OFFSET_TABLE_ + $$ - %%sub_offset wrt ..gotpc
 226       ret
 227       %%exitGG:
 228       %undef GLOBAL
 229       %define GLOBAL(x) x + %1 wrt ..gotoff
 230       %undef RESTORE_GOT
 231       %define RESTORE_GOT pop %1
 232     %endmacro
 233   %elifidn __OUTPUT_FORMAT__,macho32
 234     %macro GET_GOT 1
 235       push %1
 236       call %%get_got
 237       %%get_got:
 238       pop  %1
 239       %undef GLOBAL
 240       %define GLOBAL(x) x + %1 - %%get_got
 241       %undef RESTORE_GOT
 242       %define RESTORE_GOT pop %1
 243     %endmacro
 244   %endif
 245   %endif
 246
 247   %ifdef CHROMIUM
 248     %ifidn __OUTPUT_FORMAT__,macho32
 249       %define HIDDEN_DATA(x) x:private_extern
 250     %else
 251       %define HIDDEN_DATA(x) x
 252     %endif
 253   %else
 254     %define HIDDEN_DATA(x) x
 255   %endif
 256 %else
 257   %macro GET_GOT 1
 258   %endmacro
 259   %define GLOBAL(x) rel x
 260   %ifidn __OUTPUT_FORMAT__,elf64
 261     %define WRT_PLT wrt ..plt
 262     %define HIDDEN_DATA(x) x:data hidden
 263   %elifidn __OUTPUT_FORMAT__,elfx32
 264     %define WRT_PLT wrt ..plt
 265     %define HIDDEN_DATA(x) x:data hidden
 266   %elifidn __OUTPUT_FORMAT__,macho64
 267     %ifdef CHROMIUM
 268       %define HIDDEN_DATA(x) x:private_extern
 269     %else
 270       %define HIDDEN_DATA(x) x
 271     %endif
 272   %else
 273     %define HIDDEN_DATA(x) x
 274   %endif
 275 %endif
 276 %ifnmacro GET_GOT
 277     %macro GET_GOT 1
 278     %endmacro
 279     %define GLOBAL(x) x
 280 %endif
 281 %ifndef RESTORE_GOT
 282 %define RESTORE_GOT
 283 %endif
 284 %ifndef WRT_PLT
 285 %define WRT_PLT
 286 %endif
 287
 288 %if ABI_IS_32BIT
 289   %macro SHADOW_ARGS_TO_STACK 1
 290   %endm
 291   %define UNSHADOW_ARGS
 292 %else
 293 %if LIBAOM_YASM_WIN64
 294   %macro SHADOW_ARGS_TO_STACK 1 ; argc
 295     %if %1 > 0
 296         mov arg(0),rcx
 297     %endif
 298     %if %1 > 1
 299         mov arg(1),rdx
 300     %endif
 301     %if %1 > 2
 302         mov arg(2),r8
 303     %endif
 304     %if %1 > 3
 305         mov arg(3),r9
 306     %endif
 307   %endm
 308 %else
 309   %macro SHADOW_ARGS_TO_STACK 1 ; argc
 310     %if %1 > 0
 311         push rdi
 312     %endif
 313     %if %1 > 1
 314         push rsi
 315     %endif
 316     %if %1 > 2
 317         push rdx
 318     %endif
 319     %if %1 > 3
 320         push rcx
 321     %endif
 322     %if %1 > 4
 323         push r8
 324     %endif
 325     %if %1 > 5
 326         push r9
 327     %endif
 328     %if %1 > 6
 329       %assign i %1-6
 330       %assign off 16
 331       %rep i
 332         mov rax,[rbp+off]
 333         push rax
 334         %assign off off+8
 335       %endrep
 336     %endif
 337   %endm
 338 %endif
 339   %define UNSHADOW_ARGS mov rsp, rbp
 340 %endif
 341
 342 ; Win64 ABI requires that XMM6:XMM15 are callee saved
 343 ; SAVE_XMM n, [u]
 344 ; store registers 6-n on the stack
 345 ; if u is specified, use unaligned movs.
 346 ; Win64 ABI requires 16 byte stack alignment, but then pushes an 8 byte return
 347 ; value. Typically we follow this up with 'push rbp' - re-aligning the stack -
 348 ; but in some cases this is not done and unaligned movs must be used.
 349 %if LIBAOM_YASM_WIN64
 350 %macro SAVE_XMM 1-2 a
 351   %if %1 < 6
 352     %error Only xmm registers 6-15 must be preserved
 353   %else
 354     %assign last_xmm %1
 355     %define movxmm movdq %+ %2
 356     %assign xmm_stack_space ((last_xmm - 5) * 16)
 357     sub rsp, xmm_stack_space
 358     %assign i 6
 359     %rep (last_xmm - 5)
 360       movxmm [rsp + ((i - 6) * 16)], xmm %+ i
 361       %assign i i+1
 362     %endrep
 363   %endif
 364 %endmacro
 365 %macro RESTORE_XMM 0
 366   %ifndef last_xmm
 367     %error RESTORE_XMM must be paired with SAVE_XMM n
 368   %else
 369     %assign i last_xmm
 370     %rep (last_xmm - 5)
 371       movxmm xmm %+ i, [rsp +((i - 6) * 16)]
 372       %assign i i-1
 373     %endrep
 374     add rsp, xmm_stack_space
 375     ; there are a couple functions which return from multiple places.
 376     ; otherwise, we could uncomment these:
 377     ; %undef last_xmm
 378     ; %undef xmm_stack_space
 379     ; %undef movxmm
 380   %endif
 381 %endmacro
 382 %else
 383 %macro SAVE_XMM 1-2
 384 %endmacro
 385 %macro RESTORE_XMM 0
 386 %endmacro
 387 %endif
 388
 389 ; Name of the rodata section
 390 ;
 391 ; .rodata seems to be an elf-ism, as it doesn't work on OSX.
 392 ;
 393 %ifidn __OUTPUT_FORMAT__,macho64
 394 %define SECTION_RODATA section .text
 395 %elifidn __OUTPUT_FORMAT__,macho32
 396 %macro SECTION_RODATA 0
 397 section .text
 398 %endmacro
 399 %elifidn __OUTPUT_FORMAT__,aout
 400 %define SECTION_RODATA section .data
 401 %else
 402 %define SECTION_RODATA section .rodata
 403 %endif
 404
 405
 406 ; Tell GNU ld that we don't require an executable stack.
 407 %ifidn __OUTPUT_FORMAT__,elf32
 408 section .note.GNU-stack noalloc noexec nowrite progbits
 409 section .text
 410 %elifidn __OUTPUT_FORMAT__,elf64
 411 section .note.GNU-stack noalloc noexec nowrite progbits
 412 section .text
 413 %elifidn __OUTPUT_FORMAT__,elfx32
 414 section .note.GNU-stack noalloc noexec nowrite progbits
 415 section .text
 416 %endif