;
; jcgryss2.asm - grayscale colorspace conversion (SSE2)
;
; x86 SIMD extension for IJG JPEG library
; Copyright (C) 1999-2006, MIYASAKA Masaru.
; Copyright (C) 2011, D. R. Commander.
; 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
;
; [TAB8]

%include "jcolsamp.inc"

; --------------------------------------------------------------------------
;
; Convert some rows of samples to the output colorspace.
;
; GLOBAL(void)
; jsimd_rgb_gray_convert_sse2 (JDIMENSION img_width,
;                              JSAMPARRAY input_buf, JSAMPIMAGE output_buf,
;                              JDIMENSION output_row, int num_rows);
;

%define img_width(b)	(b)+8			; JDIMENSION img_width
%define input_buf(b)	(b)+12		; JSAMPARRAY input_buf
%define output_buf(b)	(b)+16		; JSAMPIMAGE output_buf
%define output_row(b)	(b)+20		; JDIMENSION output_row
%define num_rows(b)	(b)+24		; int num_rows

%define original_ebp	ebp+0
%define wk(i)		ebp-(WK_NUM-(i))*SIZEOF_XMMWORD	; xmmword wk[WK_NUM]
%define WK_NUM		2
%define gotptr		wk(0)-SIZEOF_POINTER	; void * gotptr

	align	16

	global	EXTN(jsimd_rgb_gray_convert_sse2) PRIVATE

EXTN(jsimd_rgb_gray_convert_sse2):
	push	ebp
	mov	eax,esp				; eax = original ebp
	sub	esp, byte 4
	and	esp, byte (-SIZEOF_XMMWORD)	; align to 128 bits
	mov	[esp],eax
	mov	ebp,esp				; ebp = aligned ebp
	lea	esp, [wk(0)]
	pushpic	eax		; make a room for GOT address
	push	ebx
;	push	ecx		; need not be preserved
;	push	edx		; need not be preserved
	push	esi
	push	edi

	get_GOT	ebx			; get GOT address
	movpic	POINTER [gotptr], ebx	; save GOT address

	mov	ecx, JDIMENSION [img_width(eax)]
	test	ecx,ecx
	jz	near .return

	push	ecx

	mov	esi, JSAMPIMAGE [output_buf(eax)]
	mov	ecx, JDIMENSION [output_row(eax)]
	mov	edi, JSAMPARRAY [esi+0*SIZEOF_JSAMPARRAY]
	lea	edi, [edi+ecx*SIZEOF_JSAMPROW]

	pop	ecx

	mov	esi, JSAMPARRAY [input_buf(eax)]
	mov	eax, INT [num_rows(eax)]
	test	eax,eax
	jle	near .return
	alignx	16,7
.rowloop:
	pushpic	eax
	push	edi
	push	esi
	push	ecx			; col

	mov	esi, JSAMPROW [esi]	; inptr
	mov	edi, JSAMPROW [edi]	; outptr0
	movpic	eax, POINTER [gotptr]	; load GOT address (eax)

	cmp	ecx, byte SIZEOF_XMMWORD
	jae	near .columnloop
	alignx	16,7

%if RGB_PIXELSIZE == 3 ; ---------------

.column_ld1:
	push	eax
	push	edx
	lea	ecx,[ecx+ecx*2]		; imul ecx,RGB_PIXELSIZE
	test	cl, SIZEOF_BYTE
	jz	short .column_ld2
	sub	ecx, byte SIZEOF_BYTE
	movzx	eax, BYTE [esi+ecx]
.column_ld2:
	test	cl, SIZEOF_WORD
	jz	short .column_ld4
	sub	ecx, byte SIZEOF_WORD
	movzx	edx, WORD [esi+ecx]
	shl	eax, WORD_BIT
	or	eax,edx
.column_ld4:
	movd	xmmA,eax
	pop	edx
	pop	eax
	test	cl, SIZEOF_DWORD
	jz	short .column_ld8
	sub	ecx, byte SIZEOF_DWORD
	movd	xmmF, XMM_DWORD [esi+ecx]
	pslldq	xmmA, SIZEOF_DWORD
	por	xmmA,xmmF
.column_ld8:
	test	cl, SIZEOF_MMWORD
	jz	short .column_ld16
	sub	ecx, byte SIZEOF_MMWORD
	movq	xmmB, XMM_MMWORD [esi+ecx]
	pslldq	xmmA, SIZEOF_MMWORD
	por	xmmA,xmmB
.column_ld16:
	test	cl, SIZEOF_XMMWORD
	jz	short .column_ld32
	movdqa	xmmF,xmmA
	movdqu	xmmA, XMMWORD [esi+0*SIZEOF_XMMWORD]
	mov	ecx, SIZEOF_XMMWORD
	jmp	short .rgb_gray_cnv
.column_ld32:
	test	cl, 2*SIZEOF_XMMWORD
	mov	ecx, SIZEOF_XMMWORD
	jz	short .rgb_gray_cnv
	movdqa	xmmB,xmmA
	movdqu	xmmA, XMMWORD [esi+0*SIZEOF_XMMWORD]
	movdqu	xmmF, XMMWORD [esi+1*SIZEOF_XMMWORD]
	jmp	short .rgb_gray_cnv
	alignx	16,7

.columnloop:
	movdqu	xmmA, XMMWORD [esi+0*SIZEOF_XMMWORD]
	movdqu	xmmF, XMMWORD [esi+1*SIZEOF_XMMWORD]
	movdqu	xmmB, XMMWORD [esi+2*SIZEOF_XMMWORD]

.rgb_gray_cnv:
	; xmmA=(00 10 20 01 11 21 02 12 22 03 13 23 04 14 24 05)
	; xmmF=(15 25 06 16 26 07 17 27 08 18 28 09 19 29 0A 1A)
	; xmmB=(2A 0B 1B 2B 0C 1C 2C 0D 1D 2D 0E 1E 2E 0F 1F 2F)

	movdqa    xmmG,xmmA
	pslldq    xmmA,8	; xmmA=(-- -- -- -- -- -- -- -- 00 10 20 01 11 21 02 12)
	psrldq    xmmG,8	; xmmG=(22 03 13 23 04 14 24 05 -- -- -- -- -- -- -- --)

	punpckhbw xmmA,xmmF	; xmmA=(00 08 10 18 20 28 01 09 11 19 21 29 02 0A 12 1A)
	pslldq    xmmF,8	; xmmF=(-- -- -- -- -- -- -- -- 15 25 06 16 26 07 17 27)

	punpcklbw xmmG,xmmB	; xmmG=(22 2A 03 0B 13 1B 23 2B 04 0C 14 1C 24 2C 05 0D)
	punpckhbw xmmF,xmmB	; xmmF=(15 1D 25 2D 06 0E 16 1E 26 2E 07 0F 17 1F 27 2F)

	movdqa    xmmD,xmmA
	pslldq    xmmA,8	; xmmA=(-- -- -- -- -- -- -- -- 00 08 10 18 20 28 01 09)
	psrldq    xmmD,8	; xmmD=(11 19 21 29 02 0A 12 1A -- -- -- -- -- -- -- --)

	punpckhbw xmmA,xmmG	; xmmA=(00 04 08 0C 10 14 18 1C 20 24 28 2C 01 05 09 0D)
	pslldq    xmmG,8	; xmmG=(-- -- -- -- -- -- -- -- 22 2A 03 0B 13 1B 23 2B)

	punpcklbw xmmD,xmmF	; xmmD=(11 15 19 1D 21 25 29 2D 02 06 0A 0E 12 16 1A 1E)
	punpckhbw xmmG,xmmF	; xmmG=(22 26 2A 2E 03 07 0B 0F 13 17 1B 1F 23 27 2B 2F)

	movdqa    xmmE,xmmA
	pslldq    xmmA,8	; xmmA=(-- -- -- -- -- -- -- -- 00 04 08 0C 10 14 18 1C)
	psrldq    xmmE,8	; xmmE=(20 24 28 2C 01 05 09 0D -- -- -- -- -- -- -- --)

	punpckhbw xmmA,xmmD	; xmmA=(00 02 04 06 08 0A 0C 0E 10 12 14 16 18 1A 1C 1E)
	pslldq    xmmD,8	; xmmD=(-- -- -- -- -- -- -- -- 11 15 19 1D 21 25 29 2D)

	punpcklbw xmmE,xmmG	; xmmE=(20 22 24 26 28 2A 2C 2E 01 03 05 07 09 0B 0D 0F)
	punpckhbw xmmD,xmmG	; xmmD=(11 13 15 17 19 1B 1D 1F 21 23 25 27 29 2B 2D 2F)

	pxor      xmmH,xmmH

	movdqa    xmmC,xmmA
	punpcklbw xmmA,xmmH	; xmmA=(00 02 04 06 08 0A 0C 0E)
	punpckhbw xmmC,xmmH	; xmmC=(10 12 14 16 18 1A 1C 1E)

	movdqa    xmmB,xmmE
	punpcklbw xmmE,xmmH	; xmmE=(20 22 24 26 28 2A 2C 2E)
	punpckhbw xmmB,xmmH	; xmmB=(01 03 05 07 09 0B 0D 0F)

	movdqa    xmmF,xmmD
	punpcklbw xmmD,xmmH	; xmmD=(11 13 15 17 19 1B 1D 1F)
	punpckhbw xmmF,xmmH	; xmmF=(21 23 25 27 29 2B 2D 2F)

%else ; RGB_PIXELSIZE == 4 ; -----------

.column_ld1:
	test	cl, SIZEOF_XMMWORD/16
	jz	short .column_ld2
	sub	ecx, byte SIZEOF_XMMWORD/16
	movd	xmmA, XMM_DWORD [esi+ecx*RGB_PIXELSIZE]
.column_ld2:
	test	cl, SIZEOF_XMMWORD/8
	jz	short .column_ld4
	sub	ecx, byte SIZEOF_XMMWORD/8
	movq	xmmE, XMM_MMWORD [esi+ecx*RGB_PIXELSIZE]
	pslldq	xmmA, SIZEOF_MMWORD
	por	xmmA,xmmE
.column_ld4:
	test	cl, SIZEOF_XMMWORD/4
	jz	short .column_ld8
	sub	ecx, byte SIZEOF_XMMWORD/4
	movdqa	xmmE,xmmA
	movdqu	xmmA, XMMWORD [esi+ecx*RGB_PIXELSIZE]
.column_ld8:
	test	cl, SIZEOF_XMMWORD/2
	mov	ecx, SIZEOF_XMMWORD
	jz	short .rgb_gray_cnv
	movdqa	xmmF,xmmA
	movdqa	xmmH,xmmE
	movdqu	xmmA, XMMWORD [esi+0*SIZEOF_XMMWORD]
	movdqu	xmmE, XMMWORD [esi+1*SIZEOF_XMMWORD]
	jmp	short .rgb_gray_cnv
	alignx	16,7

.columnloop:
	movdqu	xmmA, XMMWORD [esi+0*SIZEOF_XMMWORD]
	movdqu	xmmE, XMMWORD [esi+1*SIZEOF_XMMWORD]
	movdqu	xmmF, XMMWORD [esi+2*SIZEOF_XMMWORD]
	movdqu	xmmH, XMMWORD [esi+3*SIZEOF_XMMWORD]

.rgb_gray_cnv:
	; xmmA=(00 10 20 30 01 11 21 31 02 12 22 32 03 13 23 33)
	; xmmE=(04 14 24 34 05 15 25 35 06 16 26 36 07 17 27 37)
	; xmmF=(08 18 28 38 09 19 29 39 0A 1A 2A 3A 0B 1B 2B 3B)
	; xmmH=(0C 1C 2C 3C 0D 1D 2D 3D 0E 1E 2E 3E 0F 1F 2F 3F)

	movdqa    xmmD,xmmA
	punpcklbw xmmA,xmmE	; xmmA=(00 04 10 14 20 24 30 34 01 05 11 15 21 25 31 35)
	punpckhbw xmmD,xmmE	; xmmD=(02 06 12 16 22 26 32 36 03 07 13 17 23 27 33 37)

	movdqa    xmmC,xmmF
	punpcklbw xmmF,xmmH	; xmmF=(08 0C 18 1C 28 2C 38 3C 09 0D 19 1D 29 2D 39 3D)
	punpckhbw xmmC,xmmH	; xmmC=(0A 0E 1A 1E 2A 2E 3A 3E 0B 0F 1B 1F 2B 2F 3B 3F)

	movdqa    xmmB,xmmA
	punpcklwd xmmA,xmmF	; xmmA=(00 04 08 0C 10 14 18 1C 20 24 28 2C 30 34 38 3C)
	punpckhwd xmmB,xmmF	; xmmB=(01 05 09 0D 11 15 19 1D 21 25 29 2D 31 35 39 3D)

	movdqa    xmmG,xmmD
	punpcklwd xmmD,xmmC	; xmmD=(02 06 0A 0E 12 16 1A 1E 22 26 2A 2E 32 36 3A 3E)
	punpckhwd xmmG,xmmC	; xmmG=(03 07 0B 0F 13 17 1B 1F 23 27 2B 2F 33 37 3B 3F)

	movdqa    xmmE,xmmA
	punpcklbw xmmA,xmmD	; xmmA=(00 02 04 06 08 0A 0C 0E 10 12 14 16 18 1A 1C 1E)
	punpckhbw xmmE,xmmD	; xmmE=(20 22 24 26 28 2A 2C 2E 30 32 34 36 38 3A 3C 3E)

	movdqa    xmmH,xmmB
	punpcklbw xmmB,xmmG	; xmmB=(01 03 05 07 09 0B 0D 0F 11 13 15 17 19 1B 1D 1F)
	punpckhbw xmmH,xmmG	; xmmH=(21 23 25 27 29 2B 2D 2F 31 33 35 37 39 3B 3D 3F)

	pxor      xmmF,xmmF

	movdqa    xmmC,xmmA
	punpcklbw xmmA,xmmF	; xmmA=(00 02 04 06 08 0A 0C 0E)
	punpckhbw xmmC,xmmF	; xmmC=(10 12 14 16 18 1A 1C 1E)

	movdqa    xmmD,xmmB
	punpcklbw xmmB,xmmF	; xmmB=(01 03 05 07 09 0B 0D 0F)
	punpckhbw xmmD,xmmF	; xmmD=(11 13 15 17 19 1B 1D 1F)

	movdqa    xmmG,xmmE
	punpcklbw xmmE,xmmF	; xmmE=(20 22 24 26 28 2A 2C 2E)
	punpckhbw xmmG,xmmF	; xmmG=(30 32 34 36 38 3A 3C 3E)

	punpcklbw xmmF,xmmH
	punpckhbw xmmH,xmmH
	psrlw     xmmF,BYTE_BIT	; xmmF=(21 23 25 27 29 2B 2D 2F)
	psrlw     xmmH,BYTE_BIT	; xmmH=(31 33 35 37 39 3B 3D 3F)

%endif ; RGB_PIXELSIZE ; ---------------

	; xmm0=R(02468ACE)=RE, xmm2=G(02468ACE)=GE, xmm4=B(02468ACE)=BE
	; xmm1=R(13579BDF)=RO, xmm3=G(13579BDF)=GO, xmm5=B(13579BDF)=BO

	; (Original)
	; Y  =  0.29900 * R + 0.58700 * G + 0.11400 * B
	;
	; (This implementation)
	; Y  =  0.29900 * R + 0.33700 * G + 0.11400 * B + 0.25000 * G

	movdqa    xmm6,xmm1
	punpcklwd xmm1,xmm3
	punpckhwd xmm6,xmm3
	pmaddwd   xmm1,[GOTOFF(eax,PW_F0299_F0337)] ; xmm1=ROL*FIX(0.299)+GOL*FIX(0.337)
	pmaddwd   xmm6,[GOTOFF(eax,PW_F0299_F0337)] ; xmm6=ROH*FIX(0.299)+GOH*FIX(0.337)

	movdqa    xmm7, xmm6	; xmm7=ROH*FIX(0.299)+GOH*FIX(0.337)

	movdqa    xmm6,xmm0
	punpcklwd xmm0,xmm2
	punpckhwd xmm6,xmm2
	pmaddwd   xmm0,[GOTOFF(eax,PW_F0299_F0337)] ; xmm0=REL*FIX(0.299)+GEL*FIX(0.337)
	pmaddwd   xmm6,[GOTOFF(eax,PW_F0299_F0337)] ; xmm6=REH*FIX(0.299)+GEH*FIX(0.337)

	movdqa    XMMWORD [wk(0)], xmm0	; wk(0)=REL*FIX(0.299)+GEL*FIX(0.337)
	movdqa    XMMWORD [wk(1)], xmm6	; wk(1)=REH*FIX(0.299)+GEH*FIX(0.337)

	movdqa    xmm0, xmm5	; xmm0=BO
	movdqa    xmm6, xmm4	; xmm6=BE

	movdqa    xmm4,xmm0
	punpcklwd xmm0,xmm3
	punpckhwd xmm4,xmm3
	pmaddwd   xmm0,[GOTOFF(eax,PW_F0114_F0250)] ; xmm0=BOL*FIX(0.114)+GOL*FIX(0.250)
	pmaddwd   xmm4,[GOTOFF(eax,PW_F0114_F0250)] ; xmm4=BOH*FIX(0.114)+GOH*FIX(0.250)

	movdqa    xmm3,[GOTOFF(eax,PD_ONEHALF)]	; xmm3=[PD_ONEHALF]

	paddd     xmm0, xmm1
	paddd     xmm4, xmm7
	paddd     xmm0,xmm3
	paddd     xmm4,xmm3
	psrld     xmm0,SCALEBITS	; xmm0=YOL
	psrld     xmm4,SCALEBITS	; xmm4=YOH
	packssdw  xmm0,xmm4		; xmm0=YO

	movdqa    xmm4,xmm6
	punpcklwd xmm6,xmm2
	punpckhwd xmm4,xmm2
	pmaddwd   xmm6,[GOTOFF(eax,PW_F0114_F0250)] ; xmm6=BEL*FIX(0.114)+GEL*FIX(0.250)
	pmaddwd   xmm4,[GOTOFF(eax,PW_F0114_F0250)] ; xmm4=BEH*FIX(0.114)+GEH*FIX(0.250)

	movdqa    xmm2,[GOTOFF(eax,PD_ONEHALF)]	; xmm2=[PD_ONEHALF]

	paddd     xmm6, XMMWORD [wk(0)]
	paddd     xmm4, XMMWORD [wk(1)]
	paddd     xmm6,xmm2
	paddd     xmm4,xmm2
	psrld     xmm6,SCALEBITS	; xmm6=YEL
	psrld     xmm4,SCALEBITS	; xmm4=YEH
	packssdw  xmm6,xmm4		; xmm6=YE

	psllw     xmm0,BYTE_BIT
	por       xmm6,xmm0		; xmm6=Y
	movdqa    XMMWORD [edi], xmm6	; Save Y

	sub	ecx, byte SIZEOF_XMMWORD
	add	esi, byte RGB_PIXELSIZE*SIZEOF_XMMWORD	; inptr
	add	edi, byte SIZEOF_XMMWORD		; outptr0
	cmp	ecx, byte SIZEOF_XMMWORD
	jae	near .columnloop
	test	ecx,ecx
	jnz	near .column_ld1

	pop	ecx			; col
	pop	esi
	pop	edi
	poppic	eax

	add	esi, byte SIZEOF_JSAMPROW	; input_buf
	add	edi, byte SIZEOF_JSAMPROW
	dec	eax				; num_rows
	jg	near .rowloop

.return:
	pop	edi
	pop	esi
;	pop	edx		; need not be preserved
;	pop	ecx		; need not be preserved
	pop	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	16