vpx_ports/x86_abi_support.asm

   1 ;
   2 ;  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
   3 ;
   4 ;  Use of this source code is governed by a BSD-style license
   5 ;  that can be found in the LICENSE file in the root of the source
   6 ;  tree. An additional intellectual property rights grant can be found
   7 ;  in the file PATENTS.  All contributing project authors may
   8 ;  be found in the AUTHORS file in the root of the source tree.
   9 ;
  10
  11
  12 %include "vpx_config.asm"
  13
  14 ; 32/64 bit compatibility macros
  15 ;
  16 ; In general, we make the source use 64 bit syntax, then twiddle with it using
  17 ; the preprocessor to get the 32 bit syntax on 32 bit platforms.
  18 ;
  19 %ifidn __OUTPUT_FORMAT__,elf32
  20 %define ABI_IS_32BIT 1
  21 %elifidn __OUTPUT_FORMAT__,macho32
  22 %define ABI_IS_32BIT 1
  23 %elifidn __OUTPUT_FORMAT__,win32
  24 %define ABI_IS_32BIT 1
  25 %else
  26 %define ABI_IS_32BIT 0
  27 %endif
  28
  29 %if ABI_IS_32BIT
  30 %define rax eax
  31 %define rbx ebx
  32 %define rcx ecx
  33 %define rdx edx
  34 %define rsi esi
  35 %define rdi edi
  36 %define rsp esp
  37 %define rbp ebp
  38 %define movsxd mov
  39 %macro movq 2
  40   %ifidn %1,eax
  41     movd %1,%2
  42   %elifidn %2,eax
  43     movd %1,%2
  44   %elifidn %1,ebx
  45     movd %1,%2
  46   %elifidn %2,ebx
  47     movd %1,%2
  48   %elifidn %1,ecx
  49     movd %1,%2
  50   %elifidn %2,ecx
  51     movd %1,%2
  52   %elifidn %1,edx
  53     movd %1,%2
  54   %elifidn %2,edx
  55     movd %1,%2
  56   %elifidn %1,esi
  57     movd %1,%2
  58   %elifidn %2,esi
  59     movd %1,%2
  60   %elifidn %1,edi
  61     movd %1,%2
  62   %elifidn %2,edi
  63     movd %1,%2
  64   %elifidn %1,esp
  65     movd %1,%2
  66   %elifidn %2,esp
  67     movd %1,%2
  68   %elifidn %1,ebp
  69     movd %1,%2
  70   %elifidn %2,ebp
  71     movd %1,%2
  72   %else
  73     movq %1,%2
  74   %endif
  75 %endmacro
  76 %endif
  77
  78
  79 ; sym()
  80 ; Return the proper symbol name for the target ABI.
  81 ;
  82 ; Certain ABIs, notably MS COFF and Darwin MACH-O, require that symbols
  83 ; with C linkage be prefixed with an underscore.
  84 ;
  85 %ifidn   __OUTPUT_FORMAT__,elf32
  86 %define sym(x) x
  87 %elifidn __OUTPUT_FORMAT__,elf64
  88 %define sym(x) x
  89 %elifidn __OUTPUT_FORMAT__,x64
  90 %define sym(x) x
  91 %else
  92 %define sym(x) _ %+ x
  93 %endif
  94
  95 ; arg()
  96 ; Return the address specification of the given argument
  97 ;
  98 %if ABI_IS_32BIT
  99   %define arg(x) [ebp+8+4*x]
 100 %else
 101   ; 64 bit ABI passes arguments in registers. This is a workaround to get up
 102   ; and running quickly. Relies on SHADOW_ARGS_TO_STACK
 103   %ifidn __OUTPUT_FORMAT__,x64
 104     %define arg(x) [rbp+16+8*x]
 105   %else
 106     %define arg(x) [rbp-8-8*x]
 107   %endif
 108 %endif
 109
 110 ; REG_SZ_BYTES, REG_SZ_BITS
 111 ; Size of a register
 112 %if ABI_IS_32BIT
 113 %define REG_SZ_BYTES 4
 114 %define REG_SZ_BITS  32
 115 %else
 116 %define REG_SZ_BYTES 8
 117 %define REG_SZ_BITS  64
 118 %endif
 119
 120
 121 ; ALIGN_STACK <alignment> <register>
 122 ; This macro aligns the stack to the given alignment (in bytes). The stack
 123 ; is left such that the previous value of the stack pointer is the first
 124 ; argument on the stack (ie, the inverse of this macro is 'pop rsp.')
 125 ; This macro uses one temporary register, which is not preserved, and thus
 126 ; must be specified as an argument.
 127 %macro ALIGN_STACK 2
 128     mov         %2, rsp
 129     and         rsp, -%1
 130     lea         rsp, [rsp - (%1 - REG_SZ_BYTES)]
 131     push        %2
 132 %endmacro
 133
 134
 135 ;
 136 ; The Microsoft assembler tries to impose a certain amount of type safety in
 137 ; its register usage. YASM doesn't recognize these directives, so we just
 138 ; %define them away to maintain as much compatibility as possible with the
 139 ; original inline assembler we're porting from.
 140 ;
 141 %idefine PTR
 142 %idefine XMMWORD
 143 %idefine MMWORD
 144
 145 ; PIC macros
 146 ;
 147 %if ABI_IS_32BIT
 148   %if CONFIG_PIC=1
 149   %ifidn __OUTPUT_FORMAT__,elf32
 150     %define WRT_PLT wrt ..plt
 151     %macro GET_GOT 1
 152       extern _GLOBAL_OFFSET_TABLE_
 153       push %1
 154       call %%get_got
 155       %%sub_offset:
 156       jmp %%exitGG
 157       %%get_got:
 158       mov %1, [esp]
 159       add %1, _GLOBAL_OFFSET_TABLE_ + $$ - %%sub_offset wrt ..gotpc
 160       ret
 161       %%exitGG:
 162       %undef GLOBAL
 163       %define GLOBAL(x) x + %1 wrt ..gotoff
 164       %undef RESTORE_GOT
 165       %define RESTORE_GOT pop %1
 166     %endmacro
 167   %elifidn __OUTPUT_FORMAT__,macho32
 168     %macro GET_GOT 1
 169       push %1
 170       call %%get_got
 171       %%sub_offset:
 172       jmp  %%exitGG
 173       %%get_got:
 174       mov  %1, [esp]
 175       add %1, fake_got - %%sub_offset
 176       ret
 177       %%exitGG:
 178       %undef GLOBAL
 179       %define GLOBAL(x) x + %1 - fake_got
 180       %undef RESTORE_GOT
 181       %define RESTORE_GOT pop %1
 182     %endmacro
 183   %endif
 184   %endif
 185   %define HIDDEN_DATA(x) x
 186 %else
 187   %macro GET_GOT 1
 188   %endmacro
 189   %define GLOBAL(x) rel x
 190   %ifidn __OUTPUT_FORMAT__,elf64
 191     %define WRT_PLT wrt ..plt
 192     %define HIDDEN_DATA(x) x:data hidden
 193   %else
 194     %define HIDDEN_DATA(x) x
 195   %endif
 196 %endif
 197 %ifnmacro GET_GOT
 198     %macro GET_GOT 1
 199     %endmacro
 200     %define GLOBAL(x) x
 201 %endif
 202 %ifndef RESTORE_GOT
 203 %define RESTORE_GOT
 204 %endif
 205 %ifndef WRT_PLT
 206 %define WRT_PLT
 207 %endif
 208
 209 %if ABI_IS_32BIT
 210   %macro SHADOW_ARGS_TO_STACK 1
 211   %endm
 212   %define UNSHADOW_ARGS
 213 %else
 214 %ifidn __OUTPUT_FORMAT__,x64
 215   %macro SHADOW_ARGS_TO_STACK 1 ; argc
 216     %if %1 > 0
 217         mov arg(0),rcx
 218     %endif
 219     %if %1 > 1
 220         mov arg(1),rdx
 221     %endif
 222     %if %1 > 2
 223         mov arg(2),r8
 224     %endif
 225     %if %1 > 3
 226         mov arg(3),r9
 227     %endif
 228   %endm
 229 %else
 230   %macro SHADOW_ARGS_TO_STACK 1 ; argc
 231     %if %1 > 0
 232         push rdi
 233     %endif
 234     %if %1 > 1
 235         push rsi
 236     %endif
 237     %if %1 > 2
 238         push rdx
 239     %endif
 240     %if %1 > 3
 241         push rcx
 242     %endif
 243     %if %1 > 4
 244         push r8
 245     %endif
 246     %if %1 > 5
 247         push r9
 248     %endif
 249     %if %1 > 6
 250       %assign i %1-6
 251       %assign off 16
 252       %rep i
 253         mov rax,[rbp+off]
 254         push rax
 255         %assign off off+8
 256       %endrep
 257     %endif
 258   %endm
 259 %endif
 260   %define UNSHADOW_ARGS mov rsp, rbp
 261 %endif
 262
 263 ; must keep XMM6:XMM15 (libvpx uses XMM6 and XMM7) on Win64 ABI
 264 ; rsp register has to be aligned
 265 %ifidn __OUTPUT_FORMAT__,x64
 266 %macro SAVE_XMM 0
 267   sub rsp, 32
 268   movdqa XMMWORD PTR [rsp], xmm6
 269   movdqa XMMWORD PTR [rsp+16], xmm7
 270 %endmacro
 271 %macro RESTORE_XMM 0
 272   movdqa xmm6, XMMWORD PTR [rsp]
 273   movdqa xmm7, XMMWORD PTR [rsp+16]
 274   add rsp, 32
 275 %endmacro
 276 %else
 277 %macro SAVE_XMM 0
 278 %endmacro
 279 %macro RESTORE_XMM 0
 280 %endmacro
 281 %endif
 282
 283 ; Name of the rodata section
 284 ;
 285 ; .rodata seems to be an elf-ism, as it doesn't work on OSX.
 286 ;
 287 %ifidn __OUTPUT_FORMAT__,macho64
 288 %define SECTION_RODATA section .text
 289 %elifidn __OUTPUT_FORMAT__,macho32
 290 %macro SECTION_RODATA 0
 291 section .text
 292 fake_got:
 293 %endmacro
 294 %else
 295 %define SECTION_RODATA section .rodata
 296 %endif
 297
 298
 299 ; Tell GNU ld that we don't require an executable stack.
 300 %ifidn __OUTPUT_FORMAT__,elf32
 301 section .note.GNU-stack noalloc noexec nowrite progbits
 302 section .text
 303 %elifidn __OUTPUT_FORMAT__,elf64
 304 section .note.GNU-stack noalloc noexec nowrite progbits
 305 section .text
 306 %endif
 307