With rare exceptions ...
- Always separate line continuation characters by one space from
preceding code.
- Always use two-space indentation. Never use tabs.
- Always use K&R-style conditional blocks.
- Always surround operators with spaces, except in raw assembly code.
- Always put a space after, but not before, a comma.
- Never put a space between type casts and variables/function calls.
- Never put a space between the function name and the argument list in
function declarations and prototypes.
- Always surround braces ('{' and '}') with spaces.
- Always surround statements (if, for, else, catch, while, do, switch)
with spaces.
- Always attach pointer symbols ('*' and '**') to the variable or
function name.
- Always precede pointer symbols ('*' and '**') by a space in type
casts.
- Use the MIN() macro from jpegint.h within the libjpeg and TurboJPEG
API libraries (using min() from tjutil.h is still necessary for
TJBench.)
- Where it makes sense (particularly in the TurboJPEG code), put a blank
line after variable declaration blocks.
- Always separate statements in one-liners by two spaces.
The purpose of this was to ease maintenance on my part and also to make
it easier for contributors to figure out how to format patch
submissions. This was admittedly confusing (even to me sometimes) when
we had 3 or 4 different style conventions in the same source tree. The
new convention is more consistent with the formatting of other OSS code
bases.
This commit corrects deviations from the chosen formatting style in the
libjpeg API code and reformats the TurboJPEG API code such that it
conforms to the same standard.
NOTES:
- Although it is no longer necessary for the function name in function
declarations to begin in Column 1 (this was historically necessary
because of the ansi2knr utility, which allowed libjpeg to be built
with non-ANSI compilers), we retain that formatting for the libjpeg
code because it improves readability when using libjpeg's function
attribute macros (GLOBAL(), etc.)
- This reformatting project was accomplished with the help of AStyle and
Uncrustify, although neither was completely up to the task, and thus
a great deal of manual tweaking was required. Note to developers of
code formatting utilities: the libjpeg-turbo code base is an
excellent test bed, because AFAICT, it breaks every single one of the
utilities that are currently available.
- The legacy (MMX, SSE, 3DNow!) assembly code for i386 has been
formatted to match the SSE2 code (refer to
ff5685d5344273df321eb63a005eaae19d2496e3.) I hadn't intended to
bother with this, but the Loongson MMI implementation demonstrated
that there is still academic value to the MMX implementation, as an
algorithmic model for other 64-bit vector implementations. Thus, it
is desirable to improve its readability in the same manner as that of
the SSE2 implementation.
398 lines
15 KiB
NASM
398 lines
15 KiB
NASM
;
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; jfdctfst.asm - fast integer FDCT (MMX)
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;
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; Copyright 2009 Pierre Ossman <ossman@cendio.se> for Cendio AB
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; Copyright (C) 2016, D. R. Commander.
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;
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; Based on the x86 SIMD extension for IJG JPEG library
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; Copyright (C) 1999-2006, MIYASAKA Masaru.
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; For conditions of distribution and use, see copyright notice in jsimdext.inc
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;
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; This file should be assembled with NASM (Netwide Assembler),
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; can *not* be assembled with Microsoft's MASM or any compatible
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; assembler (including Borland's Turbo Assembler).
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; NASM is available from http://nasm.sourceforge.net/ or
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; http://sourceforge.net/project/showfiles.php?group_id=6208
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;
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; This file contains a fast, not so accurate integer implementation of
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; the forward DCT (Discrete Cosine Transform). The following code is
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; based directly on the IJG's original jfdctfst.c; see the jfdctfst.c
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; for more details.
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;
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; [TAB8]
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%include "jsimdext.inc"
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%include "jdct.inc"
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; --------------------------------------------------------------------------
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%define CONST_BITS 8 ; 14 is also OK.
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%if CONST_BITS == 8
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F_0_382 equ 98 ; FIX(0.382683433)
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F_0_541 equ 139 ; FIX(0.541196100)
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F_0_707 equ 181 ; FIX(0.707106781)
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F_1_306 equ 334 ; FIX(1.306562965)
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%else
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; NASM cannot do compile-time arithmetic on floating-point constants.
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%define DESCALE(x, n) (((x) + (1 << ((n) - 1))) >> (n))
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F_0_382 equ DESCALE( 410903207, 30 - CONST_BITS) ; FIX(0.382683433)
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F_0_541 equ DESCALE( 581104887, 30 - CONST_BITS) ; FIX(0.541196100)
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F_0_707 equ DESCALE( 759250124, 30 - CONST_BITS) ; FIX(0.707106781)
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F_1_306 equ DESCALE(1402911301, 30 - CONST_BITS) ; FIX(1.306562965)
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%endif
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; --------------------------------------------------------------------------
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SECTION SEG_CONST
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; PRE_MULTIPLY_SCALE_BITS <= 2 (to avoid overflow)
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; CONST_BITS + CONST_SHIFT + PRE_MULTIPLY_SCALE_BITS == 16 (for pmulhw)
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%define PRE_MULTIPLY_SCALE_BITS 2
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%define CONST_SHIFT (16 - PRE_MULTIPLY_SCALE_BITS - CONST_BITS)
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alignz 32
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GLOBAL_DATA(jconst_fdct_ifast_mmx)
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EXTN(jconst_fdct_ifast_mmx):
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PW_F0707 times 4 dw F_0_707 << CONST_SHIFT
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PW_F0382 times 4 dw F_0_382 << CONST_SHIFT
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PW_F0541 times 4 dw F_0_541 << CONST_SHIFT
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PW_F1306 times 4 dw F_1_306 << CONST_SHIFT
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alignz 32
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; --------------------------------------------------------------------------
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SECTION SEG_TEXT
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BITS 32
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;
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; Perform the forward DCT on one block of samples.
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;
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; GLOBAL(void)
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; jsimd_fdct_ifast_mmx(DCTELEM *data)
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;
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%define data(b) (b) + 8 ; DCTELEM *data
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%define original_ebp ebp + 0
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%define wk(i) ebp - (WK_NUM - (i)) * SIZEOF_MMWORD ; mmword wk[WK_NUM]
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%define WK_NUM 2
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align 32
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GLOBAL_FUNCTION(jsimd_fdct_ifast_mmx)
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EXTN(jsimd_fdct_ifast_mmx):
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push ebp
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mov eax, esp ; eax = original ebp
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sub esp, byte 4
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and esp, byte (-SIZEOF_MMWORD) ; align to 64 bits
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mov [esp], eax
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mov ebp, esp ; ebp = aligned ebp
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lea esp, [wk(0)]
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pushpic ebx
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; push ecx ; need not be preserved
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; push edx ; need not be preserved
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; push esi ; unused
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; push edi ; unused
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get_GOT ebx ; get GOT address
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; ---- Pass 1: process rows.
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mov edx, POINTER [data(eax)] ; (DCTELEM *)
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mov ecx, DCTSIZE/4
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alignx 16, 7
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.rowloop:
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movq mm0, MMWORD [MMBLOCK(2,0,edx,SIZEOF_DCTELEM)]
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movq mm1, MMWORD [MMBLOCK(3,0,edx,SIZEOF_DCTELEM)]
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movq mm2, MMWORD [MMBLOCK(2,1,edx,SIZEOF_DCTELEM)]
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movq mm3, MMWORD [MMBLOCK(3,1,edx,SIZEOF_DCTELEM)]
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; mm0=(20 21 22 23), mm2=(24 25 26 27)
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; mm1=(30 31 32 33), mm3=(34 35 36 37)
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movq mm4, mm0 ; transpose coefficients(phase 1)
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punpcklwd mm0, mm1 ; mm0=(20 30 21 31)
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punpckhwd mm4, mm1 ; mm4=(22 32 23 33)
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movq mm5, mm2 ; transpose coefficients(phase 1)
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punpcklwd mm2, mm3 ; mm2=(24 34 25 35)
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punpckhwd mm5, mm3 ; mm5=(26 36 27 37)
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movq mm6, MMWORD [MMBLOCK(0,0,edx,SIZEOF_DCTELEM)]
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movq mm7, MMWORD [MMBLOCK(1,0,edx,SIZEOF_DCTELEM)]
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movq mm1, MMWORD [MMBLOCK(0,1,edx,SIZEOF_DCTELEM)]
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movq mm3, MMWORD [MMBLOCK(1,1,edx,SIZEOF_DCTELEM)]
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; mm6=(00 01 02 03), mm1=(04 05 06 07)
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; mm7=(10 11 12 13), mm3=(14 15 16 17)
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movq MMWORD [wk(0)], mm4 ; wk(0)=(22 32 23 33)
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movq MMWORD [wk(1)], mm2 ; wk(1)=(24 34 25 35)
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movq mm4, mm6 ; transpose coefficients(phase 1)
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punpcklwd mm6, mm7 ; mm6=(00 10 01 11)
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punpckhwd mm4, mm7 ; mm4=(02 12 03 13)
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movq mm2, mm1 ; transpose coefficients(phase 1)
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punpcklwd mm1, mm3 ; mm1=(04 14 05 15)
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punpckhwd mm2, mm3 ; mm2=(06 16 07 17)
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movq mm7, mm6 ; transpose coefficients(phase 2)
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punpckldq mm6, mm0 ; mm6=(00 10 20 30)=data0
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punpckhdq mm7, mm0 ; mm7=(01 11 21 31)=data1
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movq mm3, mm2 ; transpose coefficients(phase 2)
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punpckldq mm2, mm5 ; mm2=(06 16 26 36)=data6
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punpckhdq mm3, mm5 ; mm3=(07 17 27 37)=data7
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movq mm0, mm7
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movq mm5, mm6
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psubw mm7, mm2 ; mm7=data1-data6=tmp6
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psubw mm6, mm3 ; mm6=data0-data7=tmp7
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paddw mm0, mm2 ; mm0=data1+data6=tmp1
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paddw mm5, mm3 ; mm5=data0+data7=tmp0
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movq mm2, MMWORD [wk(0)] ; mm2=(22 32 23 33)
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movq mm3, MMWORD [wk(1)] ; mm3=(24 34 25 35)
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movq MMWORD [wk(0)], mm7 ; wk(0)=tmp6
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movq MMWORD [wk(1)], mm6 ; wk(1)=tmp7
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movq mm7, mm4 ; transpose coefficients(phase 2)
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punpckldq mm4, mm2 ; mm4=(02 12 22 32)=data2
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punpckhdq mm7, mm2 ; mm7=(03 13 23 33)=data3
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movq mm6, mm1 ; transpose coefficients(phase 2)
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punpckldq mm1, mm3 ; mm1=(04 14 24 34)=data4
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punpckhdq mm6, mm3 ; mm6=(05 15 25 35)=data5
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movq mm2, mm7
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movq mm3, mm4
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paddw mm7, mm1 ; mm7=data3+data4=tmp3
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paddw mm4, mm6 ; mm4=data2+data5=tmp2
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psubw mm2, mm1 ; mm2=data3-data4=tmp4
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psubw mm3, mm6 ; mm3=data2-data5=tmp5
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; -- Even part
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movq mm1, mm5
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movq mm6, mm0
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psubw mm5, mm7 ; mm5=tmp13
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psubw mm0, mm4 ; mm0=tmp12
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paddw mm1, mm7 ; mm1=tmp10
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paddw mm6, mm4 ; mm6=tmp11
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paddw mm0, mm5
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psllw mm0, PRE_MULTIPLY_SCALE_BITS
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pmulhw mm0, [GOTOFF(ebx,PW_F0707)] ; mm0=z1
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movq mm7, mm1
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movq mm4, mm5
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psubw mm1, mm6 ; mm1=data4
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psubw mm5, mm0 ; mm5=data6
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paddw mm7, mm6 ; mm7=data0
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paddw mm4, mm0 ; mm4=data2
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movq MMWORD [MMBLOCK(0,1,edx,SIZEOF_DCTELEM)], mm1
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movq MMWORD [MMBLOCK(2,1,edx,SIZEOF_DCTELEM)], mm5
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movq MMWORD [MMBLOCK(0,0,edx,SIZEOF_DCTELEM)], mm7
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movq MMWORD [MMBLOCK(2,0,edx,SIZEOF_DCTELEM)], mm4
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; -- Odd part
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movq mm6, MMWORD [wk(0)] ; mm6=tmp6
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movq mm0, MMWORD [wk(1)] ; mm0=tmp7
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paddw mm2, mm3 ; mm2=tmp10
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paddw mm3, mm6 ; mm3=tmp11
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paddw mm6, mm0 ; mm6=tmp12, mm0=tmp7
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psllw mm2, PRE_MULTIPLY_SCALE_BITS
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psllw mm6, PRE_MULTIPLY_SCALE_BITS
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psllw mm3, PRE_MULTIPLY_SCALE_BITS
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pmulhw mm3, [GOTOFF(ebx,PW_F0707)] ; mm3=z3
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movq mm1, mm2 ; mm1=tmp10
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psubw mm2, mm6
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pmulhw mm2, [GOTOFF(ebx,PW_F0382)] ; mm2=z5
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pmulhw mm1, [GOTOFF(ebx,PW_F0541)] ; mm1=MULTIPLY(tmp10,FIX_0_54119610)
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pmulhw mm6, [GOTOFF(ebx,PW_F1306)] ; mm6=MULTIPLY(tmp12,FIX_1_30656296)
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paddw mm1, mm2 ; mm1=z2
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paddw mm6, mm2 ; mm6=z4
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movq mm5, mm0
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psubw mm0, mm3 ; mm0=z13
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paddw mm5, mm3 ; mm5=z11
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movq mm7, mm0
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movq mm4, mm5
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psubw mm0, mm1 ; mm0=data3
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psubw mm5, mm6 ; mm5=data7
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paddw mm7, mm1 ; mm7=data5
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paddw mm4, mm6 ; mm4=data1
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movq MMWORD [MMBLOCK(3,0,edx,SIZEOF_DCTELEM)], mm0
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movq MMWORD [MMBLOCK(3,1,edx,SIZEOF_DCTELEM)], mm5
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movq MMWORD [MMBLOCK(1,1,edx,SIZEOF_DCTELEM)], mm7
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movq MMWORD [MMBLOCK(1,0,edx,SIZEOF_DCTELEM)], mm4
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add edx, byte 4*DCTSIZE*SIZEOF_DCTELEM
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dec ecx
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jnz near .rowloop
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; ---- Pass 2: process columns.
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mov edx, POINTER [data(eax)] ; (DCTELEM *)
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mov ecx, DCTSIZE/4
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alignx 16, 7
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.columnloop:
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movq mm0, MMWORD [MMBLOCK(2,0,edx,SIZEOF_DCTELEM)]
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movq mm1, MMWORD [MMBLOCK(3,0,edx,SIZEOF_DCTELEM)]
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movq mm2, MMWORD [MMBLOCK(6,0,edx,SIZEOF_DCTELEM)]
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movq mm3, MMWORD [MMBLOCK(7,0,edx,SIZEOF_DCTELEM)]
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; mm0=(02 12 22 32), mm2=(42 52 62 72)
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; mm1=(03 13 23 33), mm3=(43 53 63 73)
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movq mm4, mm0 ; transpose coefficients(phase 1)
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punpcklwd mm0, mm1 ; mm0=(02 03 12 13)
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punpckhwd mm4, mm1 ; mm4=(22 23 32 33)
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movq mm5, mm2 ; transpose coefficients(phase 1)
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punpcklwd mm2, mm3 ; mm2=(42 43 52 53)
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punpckhwd mm5, mm3 ; mm5=(62 63 72 73)
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movq mm6, MMWORD [MMBLOCK(0,0,edx,SIZEOF_DCTELEM)]
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movq mm7, MMWORD [MMBLOCK(1,0,edx,SIZEOF_DCTELEM)]
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movq mm1, MMWORD [MMBLOCK(4,0,edx,SIZEOF_DCTELEM)]
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movq mm3, MMWORD [MMBLOCK(5,0,edx,SIZEOF_DCTELEM)]
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; mm6=(00 10 20 30), mm1=(40 50 60 70)
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; mm7=(01 11 21 31), mm3=(41 51 61 71)
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movq MMWORD [wk(0)], mm4 ; wk(0)=(22 23 32 33)
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movq MMWORD [wk(1)], mm2 ; wk(1)=(42 43 52 53)
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movq mm4, mm6 ; transpose coefficients(phase 1)
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punpcklwd mm6, mm7 ; mm6=(00 01 10 11)
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punpckhwd mm4, mm7 ; mm4=(20 21 30 31)
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movq mm2, mm1 ; transpose coefficients(phase 1)
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punpcklwd mm1, mm3 ; mm1=(40 41 50 51)
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punpckhwd mm2, mm3 ; mm2=(60 61 70 71)
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movq mm7, mm6 ; transpose coefficients(phase 2)
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punpckldq mm6, mm0 ; mm6=(00 01 02 03)=data0
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punpckhdq mm7, mm0 ; mm7=(10 11 12 13)=data1
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movq mm3, mm2 ; transpose coefficients(phase 2)
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punpckldq mm2, mm5 ; mm2=(60 61 62 63)=data6
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punpckhdq mm3, mm5 ; mm3=(70 71 72 73)=data7
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movq mm0, mm7
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movq mm5, mm6
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psubw mm7, mm2 ; mm7=data1-data6=tmp6
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psubw mm6, mm3 ; mm6=data0-data7=tmp7
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paddw mm0, mm2 ; mm0=data1+data6=tmp1
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paddw mm5, mm3 ; mm5=data0+data7=tmp0
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movq mm2, MMWORD [wk(0)] ; mm2=(22 23 32 33)
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movq mm3, MMWORD [wk(1)] ; mm3=(42 43 52 53)
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movq MMWORD [wk(0)], mm7 ; wk(0)=tmp6
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movq MMWORD [wk(1)], mm6 ; wk(1)=tmp7
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movq mm7, mm4 ; transpose coefficients(phase 2)
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punpckldq mm4, mm2 ; mm4=(20 21 22 23)=data2
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punpckhdq mm7, mm2 ; mm7=(30 31 32 33)=data3
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movq mm6, mm1 ; transpose coefficients(phase 2)
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punpckldq mm1, mm3 ; mm1=(40 41 42 43)=data4
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punpckhdq mm6, mm3 ; mm6=(50 51 52 53)=data5
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movq mm2, mm7
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movq mm3, mm4
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paddw mm7, mm1 ; mm7=data3+data4=tmp3
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paddw mm4, mm6 ; mm4=data2+data5=tmp2
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psubw mm2, mm1 ; mm2=data3-data4=tmp4
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psubw mm3, mm6 ; mm3=data2-data5=tmp5
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; -- Even part
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movq mm1, mm5
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movq mm6, mm0
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psubw mm5, mm7 ; mm5=tmp13
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psubw mm0, mm4 ; mm0=tmp12
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paddw mm1, mm7 ; mm1=tmp10
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paddw mm6, mm4 ; mm6=tmp11
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paddw mm0, mm5
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psllw mm0, PRE_MULTIPLY_SCALE_BITS
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pmulhw mm0, [GOTOFF(ebx,PW_F0707)] ; mm0=z1
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movq mm7, mm1
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movq mm4, mm5
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psubw mm1, mm6 ; mm1=data4
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psubw mm5, mm0 ; mm5=data6
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paddw mm7, mm6 ; mm7=data0
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paddw mm4, mm0 ; mm4=data2
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movq MMWORD [MMBLOCK(4,0,edx,SIZEOF_DCTELEM)], mm1
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movq MMWORD [MMBLOCK(6,0,edx,SIZEOF_DCTELEM)], mm5
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movq MMWORD [MMBLOCK(0,0,edx,SIZEOF_DCTELEM)], mm7
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movq MMWORD [MMBLOCK(2,0,edx,SIZEOF_DCTELEM)], mm4
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; -- Odd part
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movq mm6, MMWORD [wk(0)] ; mm6=tmp6
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movq mm0, MMWORD [wk(1)] ; mm0=tmp7
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paddw mm2, mm3 ; mm2=tmp10
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paddw mm3, mm6 ; mm3=tmp11
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paddw mm6, mm0 ; mm6=tmp12, mm0=tmp7
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psllw mm2, PRE_MULTIPLY_SCALE_BITS
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psllw mm6, PRE_MULTIPLY_SCALE_BITS
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psllw mm3, PRE_MULTIPLY_SCALE_BITS
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pmulhw mm3, [GOTOFF(ebx,PW_F0707)] ; mm3=z3
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movq mm1, mm2 ; mm1=tmp10
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psubw mm2, mm6
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pmulhw mm2, [GOTOFF(ebx,PW_F0382)] ; mm2=z5
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pmulhw mm1, [GOTOFF(ebx,PW_F0541)] ; mm1=MULTIPLY(tmp10,FIX_0_54119610)
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pmulhw mm6, [GOTOFF(ebx,PW_F1306)] ; mm6=MULTIPLY(tmp12,FIX_1_30656296)
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paddw mm1, mm2 ; mm1=z2
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paddw mm6, mm2 ; mm6=z4
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movq mm5, mm0
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psubw mm0, mm3 ; mm0=z13
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paddw mm5, mm3 ; mm5=z11
|
|
|
|
movq mm7, mm0
|
|
movq mm4, mm5
|
|
psubw mm0, mm1 ; mm0=data3
|
|
psubw mm5, mm6 ; mm5=data7
|
|
paddw mm7, mm1 ; mm7=data5
|
|
paddw mm4, mm6 ; mm4=data1
|
|
|
|
movq MMWORD [MMBLOCK(3,0,edx,SIZEOF_DCTELEM)], mm0
|
|
movq MMWORD [MMBLOCK(7,0,edx,SIZEOF_DCTELEM)], mm5
|
|
movq MMWORD [MMBLOCK(5,0,edx,SIZEOF_DCTELEM)], mm7
|
|
movq MMWORD [MMBLOCK(1,0,edx,SIZEOF_DCTELEM)], mm4
|
|
|
|
add edx, byte 4*SIZEOF_DCTELEM
|
|
dec ecx
|
|
jnz near .columnloop
|
|
|
|
emms ; empty MMX state
|
|
|
|
; pop edi ; unused
|
|
; pop esi ; unused
|
|
; pop edx ; need not be preserved
|
|
; pop ecx ; need not be preserved
|
|
poppic ebx
|
|
mov esp, ebp ; esp <- aligned ebp
|
|
pop esp ; esp <- original ebp
|
|
pop ebp
|
|
ret
|
|
|
|
; For some reason, the OS X linker does not honor the request to align the
|
|
; segment unless we do this.
|
|
align 32
|