ref: 0fc9abfbfd28f5cc423e286691aa8824cf3966c2
dir: /vpx_ports/x86_abi_support.asm/
;
; Copyright (c) 2010 The VP8 project authors. All Rights Reserved.
;
; Use of this source code is governed by a BSD-style license and patent
; grant that can be found in the LICENSE file in the root of the source
; tree. 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
%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
%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__,x64
%define sym(x) x
%else
%define sym(x) _ %+ x
%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
%ifidn __OUTPUT_FORMAT__,x64
%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
sub 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 WRT_PLT wrt ..plt
%macro GET_GOT 1
extern _GLOBAL_OFFSET_TABLE_
push %1
call %%get_got
%%get_got:
pop %1
add %1, _GLOBAL_OFFSET_TABLE_ + $$ - %%get_got wrt ..gotpc
%undef GLOBAL
%define GLOBAL + %1 wrt ..gotoff
%undef RESTORE_GOT
%define RESTORE_GOT pop %1
%endmacro
%elifidn __OUTPUT_FORMAT__,macho32
%macro GET_GOT 1
push %1
call %%get_got
%%get_got:
pop %1
add %1, fake_got - %%get_got
%undef GLOBAL
%define GLOBAL + %1 - fake_got
%undef RESTORE_GOT
%define RESTORE_GOT pop %1
%endmacro
%endif
%endif
%else
%macro GET_GOT 1
%endmacro
%define GLOBAL wrt rip
%ifidn __OUTPUT_FORMAT__,elf64
%define WRT_PLT wrt ..plt
%endif
%endif
%ifnmacro GET_GOT
%macro GET_GOT 1
%endmacro
%define GLOBAL
%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
%ifidn __OUTPUT_FORMAT__,x64
%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
mov rax,[rbp+16]
push rax
%endif
%if %1 > 7
mov rax,[rbp+24]
push rax
%endif
%if %1 > 8
mov rax,[rbp+32]
push rax
%endif
%endm
%endif
%define UNSHADOW_ARGS mov rsp, rbp
%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
fake_got:
%endmacro
%else
%define SECTION_RODATA section .rodata
%endif