import yasm macros from x264

Originally committed as revision 14697 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 546 insertions, 0 deletions

diff --git a/libavcodec/i386/x86inc.asm b/libavcodec/i386/x86inc.asm
new file mode 100644
index 0000000000..54c4679669
--- /dev/null
+++ b/libavcodec/i386/x86inc.asm
@@ -0,0 +1,546 @@
+;*****************************************************************************
+;* x86inc.asm
+;*****************************************************************************
+;* Copyright (C) 2005-2008 Loren Merritt <lorenm@u.washington.edu>
+;*
+;* This file is part of FFmpeg.
+;*
+;* FFmpeg is free software; you can redistribute it and/or
+;* modify it under the terms of the GNU Lesser General Public
+;* License as published by the Free Software Foundation; either
+;* version 2.1 of the License, or (at your option) any later version.
+;*
+;* FFmpeg is distributed in the hope that it will be useful,
+;* but WITHOUT ANY WARRANTY; without even the implied warranty of
+;* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+;* Lesser General Public License for more details.
+;*
+;* You should have received a copy of the GNU Lesser General Public
+;* License along with FFmpeg; if not, write to the Free Software
+;* 51, Inc., Foundation Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+;*****************************************************************************
+
+; FIXME: All of the 64bit asm functions that take a stride as an argument
+; via register, assume that the high dword of that register is filled with 0.
+; This is true in practice (since we never do any 64bit arithmetic on strides,
+; and x264's strides are all positive), but is not guaranteed by the ABI.
+
+; Name of the .rodata section.
+; Kludge: Something on OS X fails to align .rodata even given an align attribute,
+; so use a different read-only section.
+%macro SECTION_RODATA 0
+    %ifidn __OUTPUT_FORMAT__,macho64
+        SECTION .text align=16
+    %elifidn __OUTPUT_FORMAT__,macho
+        SECTION .text align=16
+        fakegot:
+    %else
+        SECTION .rodata align=16
+    %endif
+%endmacro
+
+; PIC support macros. All these macros are totally harmless when PIC is
+; not defined but can ruin everything if misused in PIC mode. On x86_32, shared
+; objects cannot directly access global variables by address, they need to
+; go through the GOT (global offset table). Most OSes do not care about it
+; and let you load non-shared .so objects (Linux, Win32...). However, OS X
+; requires PIC code in its .dylib objects.
+;
+; - GLOBAL should be used as a suffix for global addressing, eg.
+;     picgetgot ebx
+;     mov eax, [foo GLOBAL]
+;   instead of
+;     mov eax, [foo]
+;
+; - picgetgot computes the GOT address into the given register in PIC
+;   mode, otherwise does nothing. You need to do this before using GLOBAL.
+;   Before in both execution order and compiled code order (so GLOBAL knows
+;   which register the GOT is in).
+
+%ifndef PIC
+    %define GLOBAL
+    %macro picgetgot 1
+    %endmacro
+%elifdef ARCH_X86_64
+    %define PIC64
+    %define GLOBAL wrt rip
+    %macro picgetgot 1
+    %endmacro
+%else
+    %define PIC32
+    %ifidn __OUTPUT_FORMAT__,macho
+        ; There is no real global offset table on OS X, but we still
+        ; need to reference our variables by offset.
+        %macro picgetgot 1
+            call %%getgot
+          %%getgot:
+            pop %1
+            add %1, $$ - %%getgot
+            %undef GLOBAL
+            %define GLOBAL + %1 - fakegot
+        %endmacro
+    %else ; elf
+        extern _GLOBAL_OFFSET_TABLE_
+        %macro picgetgot 1
+            call %%getgot
+          %%getgot:
+            pop %1
+            add %1, _GLOBAL_OFFSET_TABLE_ + $$ - %%getgot wrt ..gotpc
+            %undef GLOBAL
+            %define GLOBAL + %1 wrt ..gotoff
+        %endmacro
+    %endif
+%endif
+
+; Macros to eliminate most code duplication between x86_32 and x86_64:
+; Currently this works only for leaf functions which load all their arguments
+; into registers at the start, and make no other use of the stack. Luckily that
+; covers most of x264's asm.
+
+; PROLOGUE:
+; %1 = number of arguments. loads them from stack if needed.
+; %2 = number of registers used, not including PIC. pushes callee-saved regs if needed.
+; %3 = whether global constants are used in this function. inits x86_32 PIC if needed.
+; %4 = list of names to define to registers
+; PROLOGUE can also be invoked by adding the same options to cglobal
+
+; e.g.
+; cglobal foo, 2,3,0, dst, src, tmp
+; declares a function (foo), taking two args (dst and src), one local variable (tmp), and not using globals
+
+; TODO Some functions can use some args directly from the stack. If they're the
+; last args then you can just not declare them, but if they're in the middle
+; we need more flexible macro.
+
+; RET:
+; Pops anything that was pushed by PROLOGUE
+
+; REP_RET:
+; Same, but if it doesn't pop anything it becomes a 2-byte ret, for athlons
+; which are slow when a normal ret follows a branch.
+
+%macro DECLARE_REG 6
+    %define r%1q %2
+    %define r%1d %3
+    %define r%1w %4
+    %define r%1b %5
+    %define r%1m %6
+    %define r%1  %2
+%endmacro
+
+%macro DECLARE_REG_SIZE 2
+    %define r%1q r%1
+    %define e%1q r%1
+    %define r%1d e%1
+    %define e%1d e%1
+    %define r%1w %1
+    %define e%1w %1
+    %define r%1b %2
+    %define e%1b %2
+%ifndef ARCH_X86_64
+    %define r%1  e%1
+%endif
+%endmacro
+
+DECLARE_REG_SIZE ax, al
+DECLARE_REG_SIZE bx, bl
+DECLARE_REG_SIZE cx, cl
+DECLARE_REG_SIZE dx, dl
+DECLARE_REG_SIZE si, sil
+DECLARE_REG_SIZE di, dil
+DECLARE_REG_SIZE bp, bpl
+
+%ifdef ARCH_X86_64
+    %define gprsize 8
+%else
+    %define gprsize 4
+%endif
+
+%macro PUSH 1
+    push %1
+    %assign stack_offset stack_offset+gprsize
+%endmacro
+
+%macro POP 1
+    pop %1
+    %assign stack_offset stack_offset-gprsize
+%endmacro
+
+%macro SUB 2
+    sub %1, %2
+    %ifidn %1, rsp
+        %assign stack_offset stack_offset+(%2)
+    %endif
+%endmacro
+
+%macro ADD 2
+    add %1, %2
+    %ifidn %1, rsp
+        %assign stack_offset stack_offset-(%2)
+    %endif
+%endmacro
+
+%macro movifnidn 2
+    %ifnidn %1, %2
+        mov %1, %2
+    %endif
+%endmacro
+
+%macro movsxdifnidn 2
+    %ifnidn %1, %2
+        movsxd %1, %2
+    %endif
+%endmacro
+
+%macro ASSERT 1
+    %if (%1) == 0
+        %error assert failed
+    %endif
+%endmacro
+
+%macro DEFINE_ARGS 0-*
+    %ifdef n_arg_names
+        %assign %%i 0
+        %rep n_arg_names
+            CAT_UNDEF arg_name %+ %%i, q
+            CAT_UNDEF arg_name %+ %%i, d
+            CAT_UNDEF arg_name %+ %%i, w
+            CAT_UNDEF arg_name %+ %%i, b
+            CAT_UNDEF arg_name, %%i
+            %assign %%i %%i+1
+        %endrep
+    %endif
+
+    %assign %%i 0
+    %rep %0
+        %xdefine %1q r %+ %%i %+ q
+        %xdefine %1d r %+ %%i %+ d
+        %xdefine %1w r %+ %%i %+ w
+        %xdefine %1b r %+ %%i %+ b
+        CAT_XDEFINE arg_name, %%i, %1
+        %assign %%i %%i+1
+        %rotate 1
+    %endrep
+    %assign n_arg_names %%i
+%endmacro
+
+%ifdef ARCH_X86_64 ;==========================================================
+%ifidn __OUTPUT_FORMAT__,win32
+
+DECLARE_REG 0, rcx, ecx, cx,  cl,  ecx
+DECLARE_REG 1, rdx, edx, dx,  dl,  edx
+DECLARE_REG 2, r8,  r8d, r8w, r8b, r8d
+DECLARE_REG 3, r9,  r9d, r9w, r9b, r9d
+DECLARE_REG 4, rdi, edi, di,  dil, [rsp + stack_offset + 40]
+DECLARE_REG 5, rsi, esi, si,  sil, [rsp + stack_offset + 48]
+DECLARE_REG 6, rax, eax, ax,  al,  [rsp + stack_offset + 56]
+%define r7m [rsp + stack_offset + 64]
+%define r8m [rsp + stack_offset + 72]
+
+%macro LOAD_IF_USED 2 ; reg_id, number_of_args
+    %if %1 < %2
+        mov r%1, [rsp + 8 + %1*8]
+    %endif
+%endmacro
+
+%else ;=======================================================================
+
+DECLARE_REG 0, rdi, edi, di,  dil, edi
+DECLARE_REG 1, rsi, esi, si,  sil, esi
+DECLARE_REG 2, rdx, edx, dx,  dl,  edx
+DECLARE_REG 3, rcx, ecx, cx,  cl,  ecx
+DECLARE_REG 4, r8,  r8d, r8w, r8b, r8d
+DECLARE_REG 5, r9,  r9d, r9w, r9b, r9d
+DECLARE_REG 6, rax, eax, ax,  al,  [rsp + stack_offset + 8]
+%define r7m [rsp + stack_offset + 16]
+%define r8m [rsp + stack_offset + 24]
+
+%macro LOAD_IF_USED 2 ; reg_id, number_of_args
+    %if %1 < %2
+        mov r%1, [rsp - 40 + %1*8]
+    %endif
+%endmacro
+
+%endif ; !WIN64
+
+%macro PROLOGUE 2-4+ 0 ; #args, #regs, pic, arg_names...
+    ASSERT %2 >= %1
+    ASSERT %2 <= 7
+    %assign stack_offset 0
+%ifidn __OUTPUT_FORMAT__,win32
+    LOAD_IF_USED 4, %1
+    LOAD_IF_USED 5, %1
+%endif
+    LOAD_IF_USED 6, %1
+    DEFINE_ARGS %4
+%endmacro
+
+%macro RET 0
+    ret
+%endmacro
+
+%macro REP_RET 0
+    rep ret
+%endmacro
+
+%else ; X86_32 ;==============================================================
+
+DECLARE_REG 0, eax, eax, ax, al,   [esp + stack_offset + 4]
+DECLARE_REG 1, ecx, ecx, cx, cl,   [esp + stack_offset + 8]
+DECLARE_REG 2, edx, edx, dx, dl,   [esp + stack_offset + 12]
+DECLARE_REG 3, ebx, ebx, bx, bl,   [esp + stack_offset + 16]
+DECLARE_REG 4, esi, esi, si, null, [esp + stack_offset + 20]
+DECLARE_REG 5, edi, edi, di, null, [esp + stack_offset + 24]
+DECLARE_REG 6, ebp, ebp, bp, null, [esp + stack_offset + 28]
+%define r7m [esp + stack_offset + 32]
+%define r8m [esp + stack_offset + 36]
+%define rsp esp
+
+%macro PUSH_IF_USED 1 ; reg_id
+    %if %1 < regs_used
+        push r%1
+        %assign stack_offset stack_offset+4
+    %endif
+%endmacro
+
+%macro POP_IF_USED 1 ; reg_id
+    %if %1 < regs_used
+        pop r%1
+    %endif
+%endmacro
+
+%macro LOAD_IF_USED 2 ; reg_id, number_of_args
+    %if %1 < %2
+        mov r%1, [esp + stack_offset + 4 + %1*4]
+    %endif
+%endmacro
+
+%macro PROLOGUE 2-4+ 0 ; #args, #regs, pic, arg_names...
+    ASSERT %2 >= %1
+    %assign stack_offset 0
+    %assign regs_used %2
+    %ifdef PIC
+    %if %3
+        %assign regs_used regs_used+1
+    %endif
+    %endif
+    ASSERT regs_used <= 7
+    PUSH_IF_USED 3
+    PUSH_IF_USED 4
+    PUSH_IF_USED 5
+    PUSH_IF_USED 6
+    LOAD_IF_USED 0, %1
+    LOAD_IF_USED 1, %1
+    LOAD_IF_USED 2, %1
+    LOAD_IF_USED 3, %1
+    LOAD_IF_USED 4, %1
+    LOAD_IF_USED 5, %1
+    LOAD_IF_USED 6, %1
+    %if %3
+        picgetgot r%2
+    %endif
+    DEFINE_ARGS %4
+%endmacro
+
+%macro RET 0
+    POP_IF_USED 6
+    POP_IF_USED 5
+    POP_IF_USED 4
+    POP_IF_USED 3
+    ret
+%endmacro
+
+%macro REP_RET 0
+    %if regs_used > 3
+        RET
+    %else
+        rep ret
+    %endif
+%endmacro
+
+%endif ;======================================================================
+
+
+
+;=============================================================================
+; arch-independent part
+;=============================================================================
+
+%assign function_align 16
+
+; Symbol prefix for C linkage
+%macro cglobal 1-2+
+    %ifidn __OUTPUT_FORMAT__,elf
+        %ifdef PREFIX
+            global _%1:function hidden
+            %define %1 _%1
+        %else
+            global %1:function hidden
+        %endif
+    %else
+        %ifdef PREFIX
+            global _%1
+            %define %1 _%1
+        %else
+            global %1
+        %endif
+    %endif
+    align function_align
+    %1:
+    RESET_MM_PERMUTATION ; not really needed, but makes disassembly somewhat nicer
+    %if %0 > 1
+        PROLOGUE %2
+    %endif
+%endmacro
+
+%macro cextern 1
+    %ifdef PREFIX
+        extern _%1
+        %define %1 _%1
+    %else
+        extern %1
+    %endif
+%endmacro
+
+; This is needed for ELF, otherwise the GNU linker assumes the stack is
+; executable by default.
+%ifidn __OUTPUT_FORMAT__,elf
+SECTION .note.GNU-stack noalloc noexec nowrite progbits
+%endif
+
+%assign FENC_STRIDE 16
+%assign FDEC_STRIDE 32
+
+; merge mmx and sse*
+
+%macro CAT_XDEFINE 3
+    %xdefine %1%2 %3
+%endmacro
+
+%macro CAT_UNDEF 2
+    %undef %1%2
+%endmacro
+
+%macro INIT_MMX 0
+    %define RESET_MM_PERMUTATION INIT_MMX
+    %define mmsize 8
+    %define num_mmregs 8
+    %define mova movq
+    %define movu movq
+    %define movh movd
+    %define movnt movntq
+    %assign %%i 0
+    %rep 8
+    CAT_XDEFINE m, %%i, mm %+ %%i
+    CAT_XDEFINE nmm, %%i, %%i
+    %assign %%i %%i+1
+    %endrep
+    %rep 8
+    CAT_UNDEF m, %%i
+    CAT_UNDEF nmm, %%i
+    %assign %%i %%i+1
+    %endrep
+%endmacro
+
+%macro INIT_XMM 0
+    %define RESET_MM_PERMUTATION INIT_XMM
+    %define mmsize 16
+    %define num_mmregs 8
+    %ifdef ARCH_X86_64
+    %define num_mmregs 16
+    %endif
+    %define mova movdqa
+    %define movu movdqu
+    %define movh movq
+    %define movnt movntdq
+    %assign %%i 0
+    %rep num_mmregs
+    CAT_XDEFINE m, %%i, xmm %+ %%i
+    CAT_XDEFINE nxmm, %%i, %%i
+    %assign %%i %%i+1
+    %endrep
+%endmacro
+
+INIT_MMX
+
+; I often want to use macros that permute their arguments. e.g. there's no
+; efficient way to implement butterfly or transpose or dct without swapping some
+; arguments.
+;
+; I would like to not have to manually keep track of the permutations:
+; If I insert a permutation in the middle of a function, it should automatically
+; change everything that follows. For more complex macros I may also have multiple
+; implementations, e.g. the SSE2 and SSSE3 versions may have different permutations.
+;
+; Hence these macros. Insert a PERMUTE or some SWAPs at the end of a macro that
+; permutes its arguments. It's equivalent to exchanging the contents of the
+; registers, except that this way you exchange the register names instead, so it
+; doesn't cost any cycles.
+
+%macro PERMUTE 2-* ; takes a list of pairs to swap
+%rep %0/2
+    %xdefine tmp%2 m%2
+    %xdefine ntmp%2 nm%2
+    %rotate 2
+%endrep
+%rep %0/2
+    %xdefine m%1 tmp%2
+    %xdefine nm%1 ntmp%2
+    %undef tmp%2
+    %undef ntmp%2
+    %rotate 2
+%endrep
+%endmacro
+
+%macro SWAP 2-* ; swaps a single chain (sometimes more concise than pairs)
+%rep %0-1
+%ifdef m%1
+    %xdefine tmp m%1
+    %xdefine m%1 m%2
+    %xdefine m%2 tmp
+    CAT_XDEFINE n, m%1, %1
+    CAT_XDEFINE n, m%2, %2
+%else
+    ; If we were called as "SWAP m0,m1" rather than "SWAP 0,1" infer the original numbers here.
+    ; Be careful using this mode in nested macros though, as in some cases there may be
+    ; other copies of m# that have already been dereferenced and don't get updated correctly.
+    %xdefine %%n1 n %+ %1
+    %xdefine %%n2 n %+ %2
+    %xdefine tmp m %+ %%n1
+    CAT_XDEFINE m, %%n1, m %+ %%n2
+    CAT_XDEFINE m, %%n2, tmp
+    CAT_XDEFINE n, m %+ %%n1, %%n1
+    CAT_XDEFINE n, m %+ %%n2, %%n2
+%endif
+    %undef tmp
+    %rotate 1
+%endrep
+%endmacro
+
+%macro SAVE_MM_PERMUTATION 1
+    %assign %%i 0
+    %rep num_mmregs
+    CAT_XDEFINE %1_m, %%i, m %+ %%i
+    %assign %%i %%i+1
+    %endrep
+%endmacro
+
+%macro LOAD_MM_PERMUTATION 1
+    %assign %%i 0
+    %rep num_mmregs
+    CAT_XDEFINE m, %%i, %1_m %+ %%i
+    %assign %%i %%i+1
+    %endrep
+%endmacro
+
+%macro call 1
+    call %1
+    %ifdef %1_m0
+        LOAD_MM_PERMUTATION %1
+    %endif
+%endmacro
+
+; substitutions which are functionally identical but reduce code size
+%define movdqa movaps
+%define movdqu movups
+