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 ;

 ;  Copyright (c) 2010 The WebM project authors. All Rights Reserved.

 ;

 ;  Use of this source code is governed by a BSD-style license

 ;  that can be found in the LICENSE file in the root of the source

 ;  tree. An additional intellectual property rights grant can be found

 ;  in the file PATENTS.  All contributing project authors may

 ;  be found in the AUTHORS file in the root of the source tree.

 ;

 %include "vpx_config.asm"

 ; 32/64 bit compatibility macros

 ;

 ; In general, we make the source use 64 bit syntax, then twiddle with it using

 ; the preprocessor to get the 32 bit syntax on 32 bit platforms.

 ;

 %ifidn __OUTPUT_FORMAT__,elf32

 %define ABI_IS_32BIT 1

 %elifidn __OUTPUT_FORMAT__,macho32

 %define ABI_IS_32BIT 1

 %elifidn __OUTPUT_FORMAT__,win32

 %define ABI_IS_32BIT 1

 %elifidn __OUTPUT_FORMAT__,aout

 %define ABI_IS_32BIT 1

 %else

 %define ABI_IS_32BIT 0

 %endif

 %if ABI_IS_32BIT

 %define rax eax

 %define rbx ebx

 %define rcx ecx

 %define rdx edx

 %define rsi esi

 %define rdi edi

 %define rsp esp

 %define rbp ebp

 %define movsxd mov

 %macro movq 2

   %ifidn %1,eax

     movd %1,%2

   %elifidn %2,eax

     movd %1,%2

   %elifidn %1,ebx

     movd %1,%2

   %elifidn %2,ebx

     movd %1,%2

   %elifidn %1,ecx

     movd %1,%2

   %elifidn %2,ecx

     movd %1,%2

   %elifidn %1,edx

     movd %1,%2

   %elifidn %2,edx

     movd %1,%2

   %elifidn %1,esi

     movd %1,%2

   %elifidn %2,esi

     movd %1,%2

   %elifidn %1,edi

     movd %1,%2

   %elifidn %2,edi

     movd %1,%2

   %elifidn %1,esp

     movd %1,%2

   %elifidn %2,esp

     movd %1,%2

   %elifidn %1,ebp

     movd %1,%2

   %elifidn %2,ebp

     movd %1,%2

   %else

     movq %1,%2

   %endif

 %endmacro

 %endif

 ; LIBVPX_YASM_WIN64

 ; Set LIBVPX_YASM_WIN64 if output is Windows 64bit so the code will work if x64

 ; or win64 is defined on the Yasm command line.

 %ifidn __OUTPUT_FORMAT__,win64

 %define LIBVPX_YASM_WIN64 1

 %elifidn __OUTPUT_FORMAT__,x64

 %define LIBVPX_YASM_WIN64 1

 %else

 %define LIBVPX_YASM_WIN64 0

 %endif

 ; sym()

 ; Return the proper symbol name for the target ABI.

 ;

 ; Certain ABIs, notably MS COFF and Darwin MACH-O, require that symbols

 ; with C linkage be prefixed with an underscore.

 ;

 %ifidn   __OUTPUT_FORMAT__,elf32

 %define sym(x) x

 %elifidn __OUTPUT_FORMAT__,elf64

 %define sym(x) x

 %elifidn __OUTPUT_FORMAT__,elfx32

 %define sym(x) x

 %elif LIBVPX_YASM_WIN64

 %define sym(x) x

 %else

 %define sym(x) _ %+ x

 %endif

 ;  PRIVATE

 ;  Macro for the attribute to hide a global symbol for the target ABI.

 ;  This is only active if CHROMIUM is defined.

 ;

 ;  Chromium doesn't like exported global symbols due to symbol clashing with

 ;  plugins among other things.

 ;

 ;  Requires Chromium's patched copy of yasm:

 ;    http://src.chromium.org/viewvc/chrome?view=rev&revision=73761

 ;    http://www.tortall.net/projects/yasm/ticket/236

 ;

 %ifdef CHROMIUM

   %ifidn   __OUTPUT_FORMAT__,elf32

     %define PRIVATE :hidden

   %elifidn __OUTPUT_FORMAT__,elf64

     %define PRIVATE :hidden

   %elifidn __OUTPUT_FORMAT__,elfx32

     %define PRIVATE :hidden

   %elif LIBVPX_YASM_WIN64

     %define PRIVATE

   %else

     %define PRIVATE :private_extern

   %endif

 %else

   %define PRIVATE

 %endif

 ; arg()

 ; Return the address specification of the given argument

 ;

 %if ABI_IS_32BIT

   %define arg(x) [ebp+8+4*x]

 %else

   ; 64 bit ABI passes arguments in registers. This is a workaround to get up

   ; and running quickly. Relies on SHADOW_ARGS_TO_STACK

   %if LIBVPX_YASM_WIN64

     %define arg(x) [rbp+16+8*x]

   %else

     %define arg(x) [rbp-8-8*x]

   %endif

 %endif

 ; REG_SZ_BYTES, REG_SZ_BITS

 ; Size of a register

 %if ABI_IS_32BIT

 %define REG_SZ_BYTES 4

 %define REG_SZ_BITS  32

 %else

 %define REG_SZ_BYTES 8

 %define REG_SZ_BITS  64

 %endif

 ; ALIGN_STACK <alignment> <register>

 ; This macro aligns the stack to the given alignment (in bytes). The stack

 ; is left such that the previous value of the stack pointer is the first

 ; argument on the stack (ie, the inverse of this macro is 'pop rsp.')

 ; This macro uses one temporary register, which is not preserved, and thus

 ; must be specified as an argument.

 %macro ALIGN_STACK 2

     mov         %2, rsp

     and         rsp, -%1

     lea         rsp, [rsp - (%1 - REG_SZ_BYTES)]

     push        %2

 %endmacro

 ;

 ; The Microsoft assembler tries to impose a certain amount of type safety in

 ; its register usage. YASM doesn't recognize these directives, so we just

 ; %define them away to maintain as much compatibility as possible with the

 ; original inline assembler we're porting from.

 ;

 %idefine PTR

 %idefine XMMWORD

 %idefine MMWORD

 ; PIC macros

 ;

 %if ABI_IS_32BIT

   %if CONFIG_PIC=1

   %ifidn __OUTPUT_FORMAT__,elf32

     %define GET_GOT_SAVE_ARG 1

     %define WRT_PLT wrt ..plt

     %macro GET_GOT 1

       extern _GLOBAL_OFFSET_TABLE_

       push %1

       call %%get_got

       %%sub_offset:

       jmp %%exitGG

       %%get_got:

       mov %1, [esp]

       add %1, _GLOBAL_OFFSET_TABLE_ + $$ - %%sub_offset wrt ..gotpc

       ret

       %%exitGG:

       %undef GLOBAL

       %define GLOBAL(x) x + %1 wrt ..gotoff

       %undef RESTORE_GOT

       %define RESTORE_GOT pop %1

     %endmacro

   %elifidn __OUTPUT_FORMAT__,macho32

     %define GET_GOT_SAVE_ARG 1

     %macro GET_GOT 1

       push %1

       call %%get_got

       %%get_got:

       pop  %1

       %undef GLOBAL

       %define GLOBAL(x) x + %1 - %%get_got

       %undef RESTORE_GOT

       %define RESTORE_GOT pop %1

     %endmacro

   %endif

   %endif

   %ifdef CHROMIUM

     %ifidn __OUTPUT_FORMAT__,macho32

       %define HIDDEN_DATA(x) x:private_extern

     %else

       %define HIDDEN_DATA(x) x

     %endif

   %else

     %define HIDDEN_DATA(x) x

   %endif

 %else

   %macro GET_GOT 1

   %endmacro

   %define GLOBAL(x) rel x

   %ifidn __OUTPUT_FORMAT__,elf64

     %define WRT_PLT wrt ..plt

     %define HIDDEN_DATA(x) x:data hidden

   %elifidn __OUTPUT_FORMAT__,elfx32

     %define WRT_PLT wrt ..plt

     %define HIDDEN_DATA(x) x:data hidden

   %elifidn __OUTPUT_FORMAT__,macho64

     %ifdef CHROMIUM

       %define HIDDEN_DATA(x) x:private_extern

     %else

       %define HIDDEN_DATA(x) x

     %endif

   %else

     %define HIDDEN_DATA(x) x

   %endif

 %endif

 %ifnmacro GET_GOT

     %macro GET_GOT 1

     %endmacro

     %define GLOBAL(x) x

 %endif

 %ifndef RESTORE_GOT

 %define RESTORE_GOT

 %endif

 %ifndef WRT_PLT

 %define WRT_PLT

 %endif

 %if ABI_IS_32BIT

   %macro SHADOW_ARGS_TO_STACK 1

   %endm

   %define UNSHADOW_ARGS

 %else

 %if LIBVPX_YASM_WIN64

   %macro SHADOW_ARGS_TO_STACK 1 ; argc

     %if %1 > 0

         mov arg(0),rcx

     %endif

     %if %1 > 1

         mov arg(1),rdx

     %endif

     %if %1 > 2

         mov arg(2),r8

     %endif

     %if %1 > 3

         mov arg(3),r9

     %endif

   %endm

 %else

   %macro SHADOW_ARGS_TO_STACK 1 ; argc

     %if %1 > 0

         push rdi

     %endif

     %if %1 > 1

         push rsi

     %endif

     %if %1 > 2

         push rdx

     %endif

     %if %1 > 3

         push rcx

     %endif

     %if %1 > 4

         push r8

     %endif

     %if %1 > 5

         push r9

     %endif

     %if %1 > 6

       %assign i %1-6

       %assign off 16

       %rep i

         mov rax,[rbp+off]

         push rax

         %assign off off+8

       %endrep

     %endif

   %endm

 %endif

   %define UNSHADOW_ARGS mov rsp, rbp

 %endif

 ; Win64 ABI requires that XMM6:XMM15 are callee saved

 ; SAVE_XMM n, [u]

 ; store registers 6-n on the stack

 ; if u is specified, use unaligned movs.

 ; Win64 ABI requires 16 byte stack alignment, but then pushes an 8 byte return

 ; value. Typically we follow this up with 'push rbp' - re-aligning the stack -

 ; but in some cases this is not done and unaligned movs must be used.

 %if LIBVPX_YASM_WIN64

 %macro SAVE_XMM 1-2 a

   %if %1 < 6

     %error Only xmm registers 6-15 must be preserved

   %else

     %assign last_xmm %1

     %define movxmm movdq %+ %2

     %assign xmm_stack_space ((last_xmm - 5) * 16)

     sub rsp, xmm_stack_space

     %assign i 6

     %rep (last_xmm - 5)

       movxmm [rsp + ((i - 6) * 16)], xmm %+ i

       %assign i i+1

     %endrep

   %endif

 %endmacro

 %macro RESTORE_XMM 0

   %ifndef last_xmm

     %error RESTORE_XMM must be paired with SAVE_XMM n

   %else

     %assign i last_xmm

     %rep (last_xmm - 5)

       movxmm xmm %+ i, [rsp +((i - 6) * 16)]

       %assign i i-1

     %endrep

     add rsp, xmm_stack_space

     ; there are a couple functions which return from multiple places.

     ; otherwise, we could uncomment these:

     ; %undef last_xmm

     ; %undef xmm_stack_space

     ; %undef movxmm

   %endif

 %endmacro

 %else

 %macro SAVE_XMM 1-2

 %endmacro

 %macro RESTORE_XMM 0

 %endmacro

 %endif

 ; Name of the rodata section

 ;

 ; .rodata seems to be an elf-ism, as it doesn't work on OSX.

 ;

 %ifidn __OUTPUT_FORMAT__,macho64

 %define SECTION_RODATA section .text

 %elifidn __OUTPUT_FORMAT__,macho32

 %macro SECTION_RODATA 0

 section .text

 %endmacro

 %elifidn __OUTPUT_FORMAT__,aout

 %define SECTION_RODATA section .data

 %else

 %define SECTION_RODATA section .rodata

 %endif

 ; Tell GNU ld that we don't require an executable stack.

 %ifidn __OUTPUT_FORMAT__,elf32

 section .note.GNU-stack noalloc noexec nowrite progbits

 section .text

 %elifidn __OUTPUT_FORMAT__,elf64

 section .note.GNU-stack noalloc noexec nowrite progbits

 section .text

 %elifidn __OUTPUT_FORMAT__,elfx32

 section .note.GNU-stack noalloc noexec nowrite progbits

 section .text

 %endif