Add MMX SIMD implementation of computationally intensive routines.


git-svn-id: svn://svn.code.sf.net/p/tigervnc/code/trunk@3648 3789f03b-4d11-0410-bbf8-ca57d06f2519
diff --git a/common/jpeg/simd/jfmmxint.asm b/common/jpeg/simd/jfmmxint.asm
new file mode 100644
index 0000000..87935a9
--- /dev/null
+++ b/common/jpeg/simd/jfmmxint.asm
@@ -0,0 +1,619 @@
+;
+; jfmmxint.asm - accurate integer FDCT (MMX)
+;
+; Copyright 2009 Pierre Ossman <ossman@cendio.se> for Cendio AB
+;
+; Based on
+; x86 SIMD extension for IJG JPEG library
+; Copyright (C) 1999-2006, MIYASAKA Masaru.
+; For conditions of distribution and use, see copyright notice in jsimdext.inc
+;
+; This file should be assembled with NASM (Netwide Assembler),
+; can *not* be assembled with Microsoft's MASM or any compatible
+; assembler (including Borland's Turbo Assembler).
+; NASM is available from http://nasm.sourceforge.net/ or
+; http://sourceforge.net/project/showfiles.php?group_id=6208
+;
+; This file contains a slow-but-accurate integer implementation of the
+; forward DCT (Discrete Cosine Transform). The following code is based
+; directly on the IJG's original jfdctint.c; see the jfdctint.c for
+; more details.
+;
+; [TAB8]
+
+%include "simd/jsimdext.inc"
+%include "simd/jdct.inc"
+
+; --------------------------------------------------------------------------
+
+%define CONST_BITS	13
+%define PASS1_BITS	2
+
+%define DESCALE_P1	(CONST_BITS-PASS1_BITS)
+%define DESCALE_P2	(CONST_BITS+PASS1_BITS)
+
+%if CONST_BITS == 13
+F_0_298	equ	 2446		; FIX(0.298631336)
+F_0_390	equ	 3196		; FIX(0.390180644)
+F_0_541	equ	 4433		; FIX(0.541196100)
+F_0_765	equ	 6270		; FIX(0.765366865)
+F_0_899	equ	 7373		; FIX(0.899976223)
+F_1_175	equ	 9633		; FIX(1.175875602)
+F_1_501	equ	12299		; FIX(1.501321110)
+F_1_847	equ	15137		; FIX(1.847759065)
+F_1_961	equ	16069		; FIX(1.961570560)
+F_2_053	equ	16819		; FIX(2.053119869)
+F_2_562	equ	20995		; FIX(2.562915447)
+F_3_072	equ	25172		; FIX(3.072711026)
+%else
+; NASM cannot do compile-time arithmetic on floating-point constants.
+%define DESCALE(x,n)  (((x)+(1<<((n)-1)))>>(n))
+F_0_298	equ	DESCALE( 320652955,30-CONST_BITS)	; FIX(0.298631336)
+F_0_390	equ	DESCALE( 418953276,30-CONST_BITS)	; FIX(0.390180644)
+F_0_541	equ	DESCALE( 581104887,30-CONST_BITS)	; FIX(0.541196100)
+F_0_765	equ	DESCALE( 821806413,30-CONST_BITS)	; FIX(0.765366865)
+F_0_899	equ	DESCALE( 966342111,30-CONST_BITS)	; FIX(0.899976223)
+F_1_175	equ	DESCALE(1262586813,30-CONST_BITS)	; FIX(1.175875602)
+F_1_501	equ	DESCALE(1612031267,30-CONST_BITS)	; FIX(1.501321110)
+F_1_847	equ	DESCALE(1984016188,30-CONST_BITS)	; FIX(1.847759065)
+F_1_961	equ	DESCALE(2106220350,30-CONST_BITS)	; FIX(1.961570560)
+F_2_053	equ	DESCALE(2204520673,30-CONST_BITS)	; FIX(2.053119869)
+F_2_562	equ	DESCALE(2751909506,30-CONST_BITS)	; FIX(2.562915447)
+F_3_072	equ	DESCALE(3299298341,30-CONST_BITS)	; FIX(3.072711026)
+%endif
+
+; --------------------------------------------------------------------------
+	SECTION	SEG_CONST
+
+	alignz	16
+	global	EXTN(jconst_fdct_islow_mmx)
+
+EXTN(jconst_fdct_islow_mmx):
+
+PW_F130_F054	times 2 dw  (F_0_541+F_0_765), F_0_541
+PW_F054_MF130	times 2 dw  F_0_541, (F_0_541-F_1_847)
+PW_MF078_F117	times 2 dw  (F_1_175-F_1_961), F_1_175
+PW_F117_F078	times 2 dw  F_1_175, (F_1_175-F_0_390)
+PW_MF060_MF089	times 2 dw  (F_0_298-F_0_899),-F_0_899
+PW_MF089_F060	times 2 dw -F_0_899, (F_1_501-F_0_899)
+PW_MF050_MF256	times 2 dw  (F_2_053-F_2_562),-F_2_562
+PW_MF256_F050	times 2 dw -F_2_562, (F_3_072-F_2_562)
+PD_DESCALE_P1	times 2 dd  1 << (DESCALE_P1-1)
+PD_DESCALE_P2	times 2 dd  1 << (DESCALE_P2-1)
+PW_DESCALE_P2X	times 4 dw  1 << (PASS1_BITS-1)
+
+	alignz	16
+
+; --------------------------------------------------------------------------
+	SECTION	SEG_TEXT
+	BITS	32
+;
+; Perform the forward DCT on one block of samples.
+;
+; GLOBAL(void)
+; jsimd_fdct_islow_mmx (DCTELEM * data)
+;
+
+%define data(b)		(b)+8		; DCTELEM * data
+
+%define original_ebp	ebp+0
+%define wk(i)		ebp-(WK_NUM-(i))*SIZEOF_MMWORD	; mmword wk[WK_NUM]
+%define WK_NUM		2
+
+	align	16
+	global	EXTN(jsimd_fdct_islow_mmx)
+
+EXTN(jsimd_fdct_islow_mmx):
+	push	ebp
+	mov	eax,esp				; eax = original ebp
+	sub	esp, byte 4
+	and	esp, byte (-SIZEOF_MMWORD)	; align to 64 bits
+	mov	[esp],eax
+	mov	ebp,esp				; ebp = aligned ebp
+	lea	esp, [wk(0)]
+	pushpic	ebx
+;	push	ecx		; need not be preserved
+;	push	edx		; need not be preserved
+;	push	esi		; unused
+;	push	edi		; unused
+
+	get_GOT	ebx		; get GOT address
+
+	; ---- Pass 1: process rows.
+
+	mov	edx, POINTER [data(eax)]	; (DCTELEM *)
+	mov	ecx, DCTSIZE/4
+	alignx	16,7
+.rowloop:
+
+	movq	mm0, MMWORD [MMBLOCK(2,0,edx,SIZEOF_DCTELEM)]
+	movq	mm1, MMWORD [MMBLOCK(3,0,edx,SIZEOF_DCTELEM)]
+	movq	mm2, MMWORD [MMBLOCK(2,1,edx,SIZEOF_DCTELEM)]
+	movq	mm3, MMWORD [MMBLOCK(3,1,edx,SIZEOF_DCTELEM)]
+
+	; mm0=(20 21 22 23), mm2=(24 25 26 27)
+	; mm1=(30 31 32 33), mm3=(34 35 36 37)
+
+	movq      mm4,mm0		; transpose coefficients(phase 1)
+	punpcklwd mm0,mm1		; mm0=(20 30 21 31)
+	punpckhwd mm4,mm1		; mm4=(22 32 23 33)
+	movq      mm5,mm2		; transpose coefficients(phase 1)
+	punpcklwd mm2,mm3		; mm2=(24 34 25 35)
+	punpckhwd mm5,mm3		; mm5=(26 36 27 37)
+
+	movq	mm6, MMWORD [MMBLOCK(0,0,edx,SIZEOF_DCTELEM)]
+	movq	mm7, MMWORD [MMBLOCK(1,0,edx,SIZEOF_DCTELEM)]
+	movq	mm1, MMWORD [MMBLOCK(0,1,edx,SIZEOF_DCTELEM)]
+	movq	mm3, MMWORD [MMBLOCK(1,1,edx,SIZEOF_DCTELEM)]
+
+	; mm6=(00 01 02 03), mm1=(04 05 06 07)
+	; mm7=(10 11 12 13), mm3=(14 15 16 17)
+
+	movq	MMWORD [wk(0)], mm4	; wk(0)=(22 32 23 33)
+	movq	MMWORD [wk(1)], mm2	; wk(1)=(24 34 25 35)
+
+	movq      mm4,mm6		; transpose coefficients(phase 1)
+	punpcklwd mm6,mm7		; mm6=(00 10 01 11)
+	punpckhwd mm4,mm7		; mm4=(02 12 03 13)
+	movq      mm2,mm1		; transpose coefficients(phase 1)
+	punpcklwd mm1,mm3		; mm1=(04 14 05 15)
+	punpckhwd mm2,mm3		; mm2=(06 16 07 17)
+
+	movq      mm7,mm6		; transpose coefficients(phase 2)
+	punpckldq mm6,mm0		; mm6=(00 10 20 30)=data0
+	punpckhdq mm7,mm0		; mm7=(01 11 21 31)=data1
+	movq      mm3,mm2		; transpose coefficients(phase 2)
+	punpckldq mm2,mm5		; mm2=(06 16 26 36)=data6
+	punpckhdq mm3,mm5		; mm3=(07 17 27 37)=data7
+
+	movq	mm0,mm7
+	movq	mm5,mm6
+	psubw	mm7,mm2			; mm7=data1-data6=tmp6
+	psubw	mm6,mm3			; mm6=data0-data7=tmp7
+	paddw	mm0,mm2			; mm0=data1+data6=tmp1
+	paddw	mm5,mm3			; mm5=data0+data7=tmp0
+
+	movq	mm2, MMWORD [wk(0)]	; mm2=(22 32 23 33)
+	movq	mm3, MMWORD [wk(1)]	; mm3=(24 34 25 35)
+	movq	MMWORD [wk(0)], mm7	; wk(0)=tmp6
+	movq	MMWORD [wk(1)], mm6	; wk(1)=tmp7
+
+	movq      mm7,mm4		; transpose coefficients(phase 2)
+	punpckldq mm4,mm2		; mm4=(02 12 22 32)=data2
+	punpckhdq mm7,mm2		; mm7=(03 13 23 33)=data3
+	movq      mm6,mm1		; transpose coefficients(phase 2)
+	punpckldq mm1,mm3		; mm1=(04 14 24 34)=data4
+	punpckhdq mm6,mm3		; mm6=(05 15 25 35)=data5
+
+	movq	mm2,mm7
+	movq	mm3,mm4
+	paddw	mm7,mm1			; mm7=data3+data4=tmp3
+	paddw	mm4,mm6			; mm4=data2+data5=tmp2
+	psubw	mm2,mm1			; mm2=data3-data4=tmp4
+	psubw	mm3,mm6			; mm3=data2-data5=tmp5
+
+	; -- Even part
+
+	movq	mm1,mm5
+	movq	mm6,mm0
+	paddw	mm5,mm7			; mm5=tmp10
+	paddw	mm0,mm4			; mm0=tmp11
+	psubw	mm1,mm7			; mm1=tmp13
+	psubw	mm6,mm4			; mm6=tmp12
+
+	movq	mm7,mm5
+	paddw	mm5,mm0			; mm5=tmp10+tmp11
+	psubw	mm7,mm0			; mm7=tmp10-tmp11
+
+	psllw	mm5,PASS1_BITS		; mm5=data0
+	psllw	mm7,PASS1_BITS		; mm7=data4
+
+	movq	MMWORD [MMBLOCK(0,0,edx,SIZEOF_DCTELEM)], mm5
+	movq	MMWORD [MMBLOCK(0,1,edx,SIZEOF_DCTELEM)], mm7
+
+	; (Original)
+	; z1 = (tmp12 + tmp13) * 0.541196100;
+	; data2 = z1 + tmp13 * 0.765366865;
+	; data6 = z1 + tmp12 * -1.847759065;
+	;
+	; (This implementation)
+	; data2 = tmp13 * (0.541196100 + 0.765366865) + tmp12 * 0.541196100;
+	; data6 = tmp13 * 0.541196100 + tmp12 * (0.541196100 - 1.847759065);
+
+	movq      mm4,mm1		; mm1=tmp13
+	movq      mm0,mm1
+	punpcklwd mm4,mm6		; mm6=tmp12
+	punpckhwd mm0,mm6
+	movq      mm1,mm4
+	movq      mm6,mm0
+	pmaddwd   mm4,[GOTOFF(ebx,PW_F130_F054)]	; mm4=data2L
+	pmaddwd   mm0,[GOTOFF(ebx,PW_F130_F054)]	; mm0=data2H
+	pmaddwd   mm1,[GOTOFF(ebx,PW_F054_MF130)]	; mm1=data6L
+	pmaddwd   mm6,[GOTOFF(ebx,PW_F054_MF130)]	; mm6=data6H
+
+	paddd	mm4,[GOTOFF(ebx,PD_DESCALE_P1)]
+	paddd	mm0,[GOTOFF(ebx,PD_DESCALE_P1)]
+	psrad	mm4,DESCALE_P1
+	psrad	mm0,DESCALE_P1
+	paddd	mm1,[GOTOFF(ebx,PD_DESCALE_P1)]
+	paddd	mm6,[GOTOFF(ebx,PD_DESCALE_P1)]
+	psrad	mm1,DESCALE_P1
+	psrad	mm6,DESCALE_P1
+
+	packssdw  mm4,mm0		; mm4=data2
+	packssdw  mm1,mm6		; mm1=data6
+
+	movq	MMWORD [MMBLOCK(2,0,edx,SIZEOF_DCTELEM)], mm4
+	movq	MMWORD [MMBLOCK(2,1,edx,SIZEOF_DCTELEM)], mm1
+
+	; -- Odd part
+
+	movq	mm5, MMWORD [wk(0)]	; mm5=tmp6
+	movq	mm7, MMWORD [wk(1)]	; mm7=tmp7
+
+	movq	mm0,mm2			; mm2=tmp4
+	movq	mm6,mm3			; mm3=tmp5
+	paddw	mm0,mm5			; mm0=z3
+	paddw	mm6,mm7			; mm6=z4
+
+	; (Original)
+	; z5 = (z3 + z4) * 1.175875602;
+	; z3 = z3 * -1.961570560;  z4 = z4 * -0.390180644;
+	; z3 += z5;  z4 += z5;
+	;
+	; (This implementation)
+	; z3 = z3 * (1.175875602 - 1.961570560) + z4 * 1.175875602;
+	; z4 = z3 * 1.175875602 + z4 * (1.175875602 - 0.390180644);
+
+	movq      mm4,mm0
+	movq      mm1,mm0
+	punpcklwd mm4,mm6
+	punpckhwd mm1,mm6
+	movq      mm0,mm4
+	movq      mm6,mm1
+	pmaddwd   mm4,[GOTOFF(ebx,PW_MF078_F117)]	; mm4=z3L
+	pmaddwd   mm1,[GOTOFF(ebx,PW_MF078_F117)]	; mm1=z3H
+	pmaddwd   mm0,[GOTOFF(ebx,PW_F117_F078)]	; mm0=z4L
+	pmaddwd   mm6,[GOTOFF(ebx,PW_F117_F078)]	; mm6=z4H
+
+	movq	MMWORD [wk(0)], mm4	; wk(0)=z3L
+	movq	MMWORD [wk(1)], mm1	; wk(1)=z3H
+
+	; (Original)
+	; z1 = tmp4 + tmp7;  z2 = tmp5 + tmp6;
+	; tmp4 = tmp4 * 0.298631336;  tmp5 = tmp5 * 2.053119869;
+	; tmp6 = tmp6 * 3.072711026;  tmp7 = tmp7 * 1.501321110;
+	; z1 = z1 * -0.899976223;  z2 = z2 * -2.562915447;
+	; data7 = tmp4 + z1 + z3;  data5 = tmp5 + z2 + z4;
+	; data3 = tmp6 + z2 + z3;  data1 = tmp7 + z1 + z4;
+	;
+	; (This implementation)
+	; tmp4 = tmp4 * (0.298631336 - 0.899976223) + tmp7 * -0.899976223;
+	; tmp5 = tmp5 * (2.053119869 - 2.562915447) + tmp6 * -2.562915447;
+	; tmp6 = tmp5 * -2.562915447 + tmp6 * (3.072711026 - 2.562915447);
+	; tmp7 = tmp4 * -0.899976223 + tmp7 * (1.501321110 - 0.899976223);
+	; data7 = tmp4 + z3;  data5 = tmp5 + z4;
+	; data3 = tmp6 + z3;  data1 = tmp7 + z4;
+
+	movq      mm4,mm2
+	movq      mm1,mm2
+	punpcklwd mm4,mm7
+	punpckhwd mm1,mm7
+	movq      mm2,mm4
+	movq      mm7,mm1
+	pmaddwd   mm4,[GOTOFF(ebx,PW_MF060_MF089)]	; mm4=tmp4L
+	pmaddwd   mm1,[GOTOFF(ebx,PW_MF060_MF089)]	; mm1=tmp4H
+	pmaddwd   mm2,[GOTOFF(ebx,PW_MF089_F060)]	; mm2=tmp7L
+	pmaddwd   mm7,[GOTOFF(ebx,PW_MF089_F060)]	; mm7=tmp7H
+
+	paddd	mm4, MMWORD [wk(0)]	; mm4=data7L
+	paddd	mm1, MMWORD [wk(1)]	; mm1=data7H
+	paddd	mm2,mm0			; mm2=data1L
+	paddd	mm7,mm6			; mm7=data1H
+
+	paddd	mm4,[GOTOFF(ebx,PD_DESCALE_P1)]
+	paddd	mm1,[GOTOFF(ebx,PD_DESCALE_P1)]
+	psrad	mm4,DESCALE_P1
+	psrad	mm1,DESCALE_P1
+	paddd	mm2,[GOTOFF(ebx,PD_DESCALE_P1)]
+	paddd	mm7,[GOTOFF(ebx,PD_DESCALE_P1)]
+	psrad	mm2,DESCALE_P1
+	psrad	mm7,DESCALE_P1
+
+	packssdw  mm4,mm1		; mm4=data7
+	packssdw  mm2,mm7		; mm2=data1
+
+	movq	MMWORD [MMBLOCK(3,1,edx,SIZEOF_DCTELEM)], mm4
+	movq	MMWORD [MMBLOCK(1,0,edx,SIZEOF_DCTELEM)], mm2
+
+	movq      mm1,mm3
+	movq      mm7,mm3
+	punpcklwd mm1,mm5
+	punpckhwd mm7,mm5
+	movq      mm3,mm1
+	movq      mm5,mm7
+	pmaddwd   mm1,[GOTOFF(ebx,PW_MF050_MF256)]	; mm1=tmp5L
+	pmaddwd   mm7,[GOTOFF(ebx,PW_MF050_MF256)]	; mm7=tmp5H
+	pmaddwd   mm3,[GOTOFF(ebx,PW_MF256_F050)]	; mm3=tmp6L
+	pmaddwd   mm5,[GOTOFF(ebx,PW_MF256_F050)]	; mm5=tmp6H
+
+	paddd	mm1,mm0			; mm1=data5L
+	paddd	mm7,mm6			; mm7=data5H
+	paddd	mm3, MMWORD [wk(0)]	; mm3=data3L
+	paddd	mm5, MMWORD [wk(1)]	; mm5=data3H
+
+	paddd	mm1,[GOTOFF(ebx,PD_DESCALE_P1)]
+	paddd	mm7,[GOTOFF(ebx,PD_DESCALE_P1)]
+	psrad	mm1,DESCALE_P1
+	psrad	mm7,DESCALE_P1
+	paddd	mm3,[GOTOFF(ebx,PD_DESCALE_P1)]
+	paddd	mm5,[GOTOFF(ebx,PD_DESCALE_P1)]
+	psrad	mm3,DESCALE_P1
+	psrad	mm5,DESCALE_P1
+
+	packssdw  mm1,mm7		; mm1=data5
+	packssdw  mm3,mm5		; mm3=data3
+
+	movq	MMWORD [MMBLOCK(1,1,edx,SIZEOF_DCTELEM)], mm1
+	movq	MMWORD [MMBLOCK(3,0,edx,SIZEOF_DCTELEM)], mm3
+
+	add	edx, byte 4*DCTSIZE*SIZEOF_DCTELEM
+	dec	ecx
+	jnz	near .rowloop
+
+	; ---- Pass 2: process columns.
+
+	mov	edx, POINTER [data(eax)]	; (DCTELEM *)
+	mov	ecx, DCTSIZE/4
+	alignx	16,7
+.columnloop:
+
+	movq	mm0, MMWORD [MMBLOCK(2,0,edx,SIZEOF_DCTELEM)]
+	movq	mm1, MMWORD [MMBLOCK(3,0,edx,SIZEOF_DCTELEM)]
+	movq	mm2, MMWORD [MMBLOCK(6,0,edx,SIZEOF_DCTELEM)]
+	movq	mm3, MMWORD [MMBLOCK(7,0,edx,SIZEOF_DCTELEM)]
+
+	; mm0=(02 12 22 32), mm2=(42 52 62 72)
+	; mm1=(03 13 23 33), mm3=(43 53 63 73)
+
+	movq      mm4,mm0		; transpose coefficients(phase 1)
+	punpcklwd mm0,mm1		; mm0=(02 03 12 13)
+	punpckhwd mm4,mm1		; mm4=(22 23 32 33)
+	movq      mm5,mm2		; transpose coefficients(phase 1)
+	punpcklwd mm2,mm3		; mm2=(42 43 52 53)
+	punpckhwd mm5,mm3		; mm5=(62 63 72 73)
+
+	movq	mm6, MMWORD [MMBLOCK(0,0,edx,SIZEOF_DCTELEM)]
+	movq	mm7, MMWORD [MMBLOCK(1,0,edx,SIZEOF_DCTELEM)]
+	movq	mm1, MMWORD [MMBLOCK(4,0,edx,SIZEOF_DCTELEM)]
+	movq	mm3, MMWORD [MMBLOCK(5,0,edx,SIZEOF_DCTELEM)]
+
+	; mm6=(00 10 20 30), mm1=(40 50 60 70)
+	; mm7=(01 11 21 31), mm3=(41 51 61 71)
+
+	movq	MMWORD [wk(0)], mm4	; wk(0)=(22 23 32 33)
+	movq	MMWORD [wk(1)], mm2	; wk(1)=(42 43 52 53)
+
+	movq      mm4,mm6		; transpose coefficients(phase 1)
+	punpcklwd mm6,mm7		; mm6=(00 01 10 11)
+	punpckhwd mm4,mm7		; mm4=(20 21 30 31)
+	movq      mm2,mm1		; transpose coefficients(phase 1)
+	punpcklwd mm1,mm3		; mm1=(40 41 50 51)
+	punpckhwd mm2,mm3		; mm2=(60 61 70 71)
+
+	movq      mm7,mm6		; transpose coefficients(phase 2)
+	punpckldq mm6,mm0		; mm6=(00 01 02 03)=data0
+	punpckhdq mm7,mm0		; mm7=(10 11 12 13)=data1
+	movq      mm3,mm2		; transpose coefficients(phase 2)
+	punpckldq mm2,mm5		; mm2=(60 61 62 63)=data6
+	punpckhdq mm3,mm5		; mm3=(70 71 72 73)=data7
+
+	movq	mm0,mm7
+	movq	mm5,mm6
+	psubw	mm7,mm2			; mm7=data1-data6=tmp6
+	psubw	mm6,mm3			; mm6=data0-data7=tmp7
+	paddw	mm0,mm2			; mm0=data1+data6=tmp1
+	paddw	mm5,mm3			; mm5=data0+data7=tmp0
+
+	movq	mm2, MMWORD [wk(0)]	; mm2=(22 23 32 33)
+	movq	mm3, MMWORD [wk(1)]	; mm3=(42 43 52 53)
+	movq	MMWORD [wk(0)], mm7	; wk(0)=tmp6
+	movq	MMWORD [wk(1)], mm6	; wk(1)=tmp7
+
+	movq      mm7,mm4		; transpose coefficients(phase 2)
+	punpckldq mm4,mm2		; mm4=(20 21 22 23)=data2
+	punpckhdq mm7,mm2		; mm7=(30 31 32 33)=data3
+	movq      mm6,mm1		; transpose coefficients(phase 2)
+	punpckldq mm1,mm3		; mm1=(40 41 42 43)=data4
+	punpckhdq mm6,mm3		; mm6=(50 51 52 53)=data5
+
+	movq	mm2,mm7
+	movq	mm3,mm4
+	paddw	mm7,mm1			; mm7=data3+data4=tmp3
+	paddw	mm4,mm6			; mm4=data2+data5=tmp2
+	psubw	mm2,mm1			; mm2=data3-data4=tmp4
+	psubw	mm3,mm6			; mm3=data2-data5=tmp5
+
+	; -- Even part
+
+	movq	mm1,mm5
+	movq	mm6,mm0
+	paddw	mm5,mm7			; mm5=tmp10
+	paddw	mm0,mm4			; mm0=tmp11
+	psubw	mm1,mm7			; mm1=tmp13
+	psubw	mm6,mm4			; mm6=tmp12
+
+	movq	mm7,mm5
+	paddw	mm5,mm0			; mm5=tmp10+tmp11
+	psubw	mm7,mm0			; mm7=tmp10-tmp11
+
+	paddw	mm5,[GOTOFF(ebx,PW_DESCALE_P2X)]
+	paddw	mm7,[GOTOFF(ebx,PW_DESCALE_P2X)]
+	psraw	mm5,PASS1_BITS		; mm5=data0
+	psraw	mm7,PASS1_BITS		; mm7=data4
+
+	movq	MMWORD [MMBLOCK(0,0,edx,SIZEOF_DCTELEM)], mm5
+	movq	MMWORD [MMBLOCK(4,0,edx,SIZEOF_DCTELEM)], mm7
+
+	; (Original)
+	; z1 = (tmp12 + tmp13) * 0.541196100;
+	; data2 = z1 + tmp13 * 0.765366865;
+	; data6 = z1 + tmp12 * -1.847759065;
+	;
+	; (This implementation)
+	; data2 = tmp13 * (0.541196100 + 0.765366865) + tmp12 * 0.541196100;
+	; data6 = tmp13 * 0.541196100 + tmp12 * (0.541196100 - 1.847759065);
+
+	movq      mm4,mm1		; mm1=tmp13
+	movq      mm0,mm1
+	punpcklwd mm4,mm6		; mm6=tmp12
+	punpckhwd mm0,mm6
+	movq      mm1,mm4
+	movq      mm6,mm0
+	pmaddwd   mm4,[GOTOFF(ebx,PW_F130_F054)]	; mm4=data2L
+	pmaddwd   mm0,[GOTOFF(ebx,PW_F130_F054)]	; mm0=data2H
+	pmaddwd   mm1,[GOTOFF(ebx,PW_F054_MF130)]	; mm1=data6L
+	pmaddwd   mm6,[GOTOFF(ebx,PW_F054_MF130)]	; mm6=data6H
+
+	paddd	mm4,[GOTOFF(ebx,PD_DESCALE_P2)]
+	paddd	mm0,[GOTOFF(ebx,PD_DESCALE_P2)]
+	psrad	mm4,DESCALE_P2
+	psrad	mm0,DESCALE_P2
+	paddd	mm1,[GOTOFF(ebx,PD_DESCALE_P2)]
+	paddd	mm6,[GOTOFF(ebx,PD_DESCALE_P2)]
+	psrad	mm1,DESCALE_P2
+	psrad	mm6,DESCALE_P2
+
+	packssdw  mm4,mm0		; mm4=data2
+	packssdw  mm1,mm6		; mm1=data6
+
+	movq	MMWORD [MMBLOCK(2,0,edx,SIZEOF_DCTELEM)], mm4
+	movq	MMWORD [MMBLOCK(6,0,edx,SIZEOF_DCTELEM)], mm1
+
+	; -- Odd part
+
+	movq	mm5, MMWORD [wk(0)]	; mm5=tmp6
+	movq	mm7, MMWORD [wk(1)]	; mm7=tmp7
+
+	movq	mm0,mm2			; mm2=tmp4
+	movq	mm6,mm3			; mm3=tmp5
+	paddw	mm0,mm5			; mm0=z3
+	paddw	mm6,mm7			; mm6=z4
+
+	; (Original)
+	; z5 = (z3 + z4) * 1.175875602;
+	; z3 = z3 * -1.961570560;  z4 = z4 * -0.390180644;
+	; z3 += z5;  z4 += z5;
+	;
+	; (This implementation)
+	; z3 = z3 * (1.175875602 - 1.961570560) + z4 * 1.175875602;
+	; z4 = z3 * 1.175875602 + z4 * (1.175875602 - 0.390180644);
+
+	movq      mm4,mm0
+	movq      mm1,mm0
+	punpcklwd mm4,mm6
+	punpckhwd mm1,mm6
+	movq      mm0,mm4
+	movq      mm6,mm1
+	pmaddwd   mm4,[GOTOFF(ebx,PW_MF078_F117)]	; mm4=z3L
+	pmaddwd   mm1,[GOTOFF(ebx,PW_MF078_F117)]	; mm1=z3H
+	pmaddwd   mm0,[GOTOFF(ebx,PW_F117_F078)]	; mm0=z4L
+	pmaddwd   mm6,[GOTOFF(ebx,PW_F117_F078)]	; mm6=z4H
+
+	movq	MMWORD [wk(0)], mm4	; wk(0)=z3L
+	movq	MMWORD [wk(1)], mm1	; wk(1)=z3H
+
+	; (Original)
+	; z1 = tmp4 + tmp7;  z2 = tmp5 + tmp6;
+	; tmp4 = tmp4 * 0.298631336;  tmp5 = tmp5 * 2.053119869;
+	; tmp6 = tmp6 * 3.072711026;  tmp7 = tmp7 * 1.501321110;
+	; z1 = z1 * -0.899976223;  z2 = z2 * -2.562915447;
+	; data7 = tmp4 + z1 + z3;  data5 = tmp5 + z2 + z4;
+	; data3 = tmp6 + z2 + z3;  data1 = tmp7 + z1 + z4;
+	;
+	; (This implementation)
+	; tmp4 = tmp4 * (0.298631336 - 0.899976223) + tmp7 * -0.899976223;
+	; tmp5 = tmp5 * (2.053119869 - 2.562915447) + tmp6 * -2.562915447;
+	; tmp6 = tmp5 * -2.562915447 + tmp6 * (3.072711026 - 2.562915447);
+	; tmp7 = tmp4 * -0.899976223 + tmp7 * (1.501321110 - 0.899976223);
+	; data7 = tmp4 + z3;  data5 = tmp5 + z4;
+	; data3 = tmp6 + z3;  data1 = tmp7 + z4;
+
+	movq      mm4,mm2
+	movq      mm1,mm2
+	punpcklwd mm4,mm7
+	punpckhwd mm1,mm7
+	movq      mm2,mm4
+	movq      mm7,mm1
+	pmaddwd   mm4,[GOTOFF(ebx,PW_MF060_MF089)]	; mm4=tmp4L
+	pmaddwd   mm1,[GOTOFF(ebx,PW_MF060_MF089)]	; mm1=tmp4H
+	pmaddwd   mm2,[GOTOFF(ebx,PW_MF089_F060)]	; mm2=tmp7L
+	pmaddwd   mm7,[GOTOFF(ebx,PW_MF089_F060)]	; mm7=tmp7H
+
+	paddd	mm4, MMWORD [wk(0)]	; mm4=data7L
+	paddd	mm1, MMWORD [wk(1)]	; mm1=data7H
+	paddd	mm2,mm0			; mm2=data1L
+	paddd	mm7,mm6			; mm7=data1H
+
+	paddd	mm4,[GOTOFF(ebx,PD_DESCALE_P2)]
+	paddd	mm1,[GOTOFF(ebx,PD_DESCALE_P2)]
+	psrad	mm4,DESCALE_P2
+	psrad	mm1,DESCALE_P2
+	paddd	mm2,[GOTOFF(ebx,PD_DESCALE_P2)]
+	paddd	mm7,[GOTOFF(ebx,PD_DESCALE_P2)]
+	psrad	mm2,DESCALE_P2
+	psrad	mm7,DESCALE_P2
+
+	packssdw  mm4,mm1		; mm4=data7
+	packssdw  mm2,mm7		; mm2=data1
+
+	movq	MMWORD [MMBLOCK(7,0,edx,SIZEOF_DCTELEM)], mm4
+	movq	MMWORD [MMBLOCK(1,0,edx,SIZEOF_DCTELEM)], mm2
+
+	movq      mm1,mm3
+	movq      mm7,mm3
+	punpcklwd mm1,mm5
+	punpckhwd mm7,mm5
+	movq      mm3,mm1
+	movq      mm5,mm7
+	pmaddwd   mm1,[GOTOFF(ebx,PW_MF050_MF256)]	; mm1=tmp5L
+	pmaddwd   mm7,[GOTOFF(ebx,PW_MF050_MF256)]	; mm7=tmp5H
+	pmaddwd   mm3,[GOTOFF(ebx,PW_MF256_F050)]	; mm3=tmp6L
+	pmaddwd   mm5,[GOTOFF(ebx,PW_MF256_F050)]	; mm5=tmp6H
+
+	paddd	mm1,mm0			; mm1=data5L
+	paddd	mm7,mm6			; mm7=data5H
+	paddd	mm3, MMWORD [wk(0)]	; mm3=data3L
+	paddd	mm5, MMWORD [wk(1)]	; mm5=data3H
+
+	paddd	mm1,[GOTOFF(ebx,PD_DESCALE_P2)]
+	paddd	mm7,[GOTOFF(ebx,PD_DESCALE_P2)]
+	psrad	mm1,DESCALE_P2
+	psrad	mm7,DESCALE_P2
+	paddd	mm3,[GOTOFF(ebx,PD_DESCALE_P2)]
+	paddd	mm5,[GOTOFF(ebx,PD_DESCALE_P2)]
+	psrad	mm3,DESCALE_P2
+	psrad	mm5,DESCALE_P2
+
+	packssdw  mm1,mm7		; mm1=data5
+	packssdw  mm3,mm5		; mm3=data3
+
+	movq	MMWORD [MMBLOCK(5,0,edx,SIZEOF_DCTELEM)], mm1
+	movq	MMWORD [MMBLOCK(3,0,edx,SIZEOF_DCTELEM)], mm3
+
+	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
+