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1;
2; jdcolext.asm - colorspace conversion (SSE2)
3;
4; Copyright 2009, 2012 Pierre Ossman <ossman@cendio.se> for Cendio AB
5; Copyright 2012 D. R. Commander
6;
7; Based on
8; x86 SIMD extension for IJG JPEG library
9; Copyright (C) 1999-2006, MIYASAKA Masaru.
10; For conditions of distribution and use, see copyright notice in jsimdext.inc
11;
12; This file should be assembled with NASM (Netwide Assembler),
13; can *not* be assembled with Microsoft's MASM or any compatible
14; assembler (including Borland's Turbo Assembler).
15; NASM is available from http://nasm.sourceforge.net/ or
16; http://sourceforge.net/project/showfiles.php?group_id=6208
17;
18; [TAB8]
19
20%include "jcolsamp.inc"
21
22; --------------------------------------------------------------------------
23;
24; Convert some rows of samples to the output colorspace.
25;
26; GLOBAL(void)
27; jsimd_ycc_rgb_convert_sse2 (JDIMENSION out_width,
28;                             JSAMPIMAGE input_buf, JDIMENSION input_row,
29;                             JSAMPARRAY output_buf, int num_rows)
30;
31
32%define out_width(b)    (b)+8           ; JDIMENSION out_width
33%define input_buf(b)    (b)+12          ; JSAMPIMAGE input_buf
34%define input_row(b)    (b)+16          ; JDIMENSION input_row
35%define output_buf(b)   (b)+20          ; JSAMPARRAY output_buf
36%define num_rows(b)     (b)+24          ; int num_rows
37
38%define original_ebp    ebp+0
39%define wk(i)           ebp-(WK_NUM-(i))*SIZEOF_XMMWORD ; xmmword wk[WK_NUM]
40%define WK_NUM          2
41%define gotptr          wk(0)-SIZEOF_POINTER    ; void * gotptr
42
43        align   16
44        global  EXTN(jsimd_ycc_rgb_convert_sse2)
45
46EXTN(jsimd_ycc_rgb_convert_sse2):
47        push    ebp
48        mov     eax,esp                         ; eax = original ebp
49        sub     esp, byte 4
50        and     esp, byte (-SIZEOF_XMMWORD)     ; align to 128 bits
51        mov     [esp],eax
52        mov     ebp,esp                         ; ebp = aligned ebp
53        lea     esp, [wk(0)]
54        pushpic eax             ; make a room for GOT address
55        push    ebx
56;       push    ecx             ; need not be preserved
57;       push    edx             ; need not be preserved
58        push    esi
59        push    edi
60
61        get_GOT ebx                     ; get GOT address
62        movpic  POINTER [gotptr], ebx   ; save GOT address
63
64        mov     ecx, JDIMENSION [out_width(eax)]        ; num_cols
65        test    ecx,ecx
66        jz      near .return
67
68        push    ecx
69
70        mov     edi, JSAMPIMAGE [input_buf(eax)]
71        mov     ecx, JDIMENSION [input_row(eax)]
72        mov     esi, JSAMPARRAY [edi+0*SIZEOF_JSAMPARRAY]
73        mov     ebx, JSAMPARRAY [edi+1*SIZEOF_JSAMPARRAY]
74        mov     edx, JSAMPARRAY [edi+2*SIZEOF_JSAMPARRAY]
75        lea     esi, [esi+ecx*SIZEOF_JSAMPROW]
76        lea     ebx, [ebx+ecx*SIZEOF_JSAMPROW]
77        lea     edx, [edx+ecx*SIZEOF_JSAMPROW]
78
79        pop     ecx
80
81        mov     edi, JSAMPARRAY [output_buf(eax)]
82        mov     eax, INT [num_rows(eax)]
83        test    eax,eax
84        jle     near .return
85        alignx  16,7
86.rowloop:
87        push    eax
88        push    edi
89        push    edx
90        push    ebx
91        push    esi
92        push    ecx                     ; col
93
94        mov     esi, JSAMPROW [esi]     ; inptr0
95        mov     ebx, JSAMPROW [ebx]     ; inptr1
96        mov     edx, JSAMPROW [edx]     ; inptr2
97        mov     edi, JSAMPROW [edi]     ; outptr
98        movpic  eax, POINTER [gotptr]   ; load GOT address (eax)
99        alignx  16,7
100.columnloop:
101
102        movdqa  xmm5, XMMWORD [ebx]     ; xmm5=Cb(0123456789ABCDEF)
103        movdqa  xmm1, XMMWORD [edx]     ; xmm1=Cr(0123456789ABCDEF)
104
105        pcmpeqw xmm4,xmm4
106        pcmpeqw xmm7,xmm7
107        psrlw   xmm4,BYTE_BIT
108        psllw   xmm7,7                  ; xmm7={0xFF80 0xFF80 0xFF80 0xFF80 ..}
109        movdqa  xmm0,xmm4               ; xmm0=xmm4={0xFF 0x00 0xFF 0x00 ..}
110
111        pand    xmm4,xmm5               ; xmm4=Cb(02468ACE)=CbE
112        psrlw   xmm5,BYTE_BIT           ; xmm5=Cb(13579BDF)=CbO
113        pand    xmm0,xmm1               ; xmm0=Cr(02468ACE)=CrE
114        psrlw   xmm1,BYTE_BIT           ; xmm1=Cr(13579BDF)=CrO
115
116        paddw   xmm4,xmm7
117        paddw   xmm5,xmm7
118        paddw   xmm0,xmm7
119        paddw   xmm1,xmm7
120
121        ; (Original)
122        ; R = Y                + 1.40200 * Cr
123        ; G = Y - 0.34414 * Cb - 0.71414 * Cr
124        ; B = Y + 1.77200 * Cb
125        ;
126        ; (This implementation)
127        ; R = Y                + 0.40200 * Cr + Cr
128        ; G = Y - 0.34414 * Cb + 0.28586 * Cr - Cr
129        ; B = Y - 0.22800 * Cb + Cb + Cb
130
131        movdqa  xmm2,xmm4               ; xmm2=CbE
132        movdqa  xmm3,xmm5               ; xmm3=CbO
133        paddw   xmm4,xmm4               ; xmm4=2*CbE
134        paddw   xmm5,xmm5               ; xmm5=2*CbO
135        movdqa  xmm6,xmm0               ; xmm6=CrE
136        movdqa  xmm7,xmm1               ; xmm7=CrO
137        paddw   xmm0,xmm0               ; xmm0=2*CrE
138        paddw   xmm1,xmm1               ; xmm1=2*CrO
139
140        pmulhw  xmm4,[GOTOFF(eax,PW_MF0228)]    ; xmm4=(2*CbE * -FIX(0.22800))
141        pmulhw  xmm5,[GOTOFF(eax,PW_MF0228)]    ; xmm5=(2*CbO * -FIX(0.22800))
142        pmulhw  xmm0,[GOTOFF(eax,PW_F0402)]     ; xmm0=(2*CrE * FIX(0.40200))
143        pmulhw  xmm1,[GOTOFF(eax,PW_F0402)]     ; xmm1=(2*CrO * FIX(0.40200))
144
145        paddw   xmm4,[GOTOFF(eax,PW_ONE)]
146        paddw   xmm5,[GOTOFF(eax,PW_ONE)]
147        psraw   xmm4,1                  ; xmm4=(CbE * -FIX(0.22800))
148        psraw   xmm5,1                  ; xmm5=(CbO * -FIX(0.22800))
149        paddw   xmm0,[GOTOFF(eax,PW_ONE)]
150        paddw   xmm1,[GOTOFF(eax,PW_ONE)]
151        psraw   xmm0,1                  ; xmm0=(CrE * FIX(0.40200))
152        psraw   xmm1,1                  ; xmm1=(CrO * FIX(0.40200))
153
154        paddw   xmm4,xmm2
155        paddw   xmm5,xmm3
156        paddw   xmm4,xmm2               ; xmm4=(CbE * FIX(1.77200))=(B-Y)E
157        paddw   xmm5,xmm3               ; xmm5=(CbO * FIX(1.77200))=(B-Y)O
158        paddw   xmm0,xmm6               ; xmm0=(CrE * FIX(1.40200))=(R-Y)E
159        paddw   xmm1,xmm7               ; xmm1=(CrO * FIX(1.40200))=(R-Y)O
160
161        movdqa  XMMWORD [wk(0)], xmm4   ; wk(0)=(B-Y)E
162        movdqa  XMMWORD [wk(1)], xmm5   ; wk(1)=(B-Y)O
163
164        movdqa    xmm4,xmm2
165        movdqa    xmm5,xmm3
166        punpcklwd xmm2,xmm6
167        punpckhwd xmm4,xmm6
168        pmaddwd   xmm2,[GOTOFF(eax,PW_MF0344_F0285)]
169        pmaddwd   xmm4,[GOTOFF(eax,PW_MF0344_F0285)]
170        punpcklwd xmm3,xmm7
171        punpckhwd xmm5,xmm7
172        pmaddwd   xmm3,[GOTOFF(eax,PW_MF0344_F0285)]
173        pmaddwd   xmm5,[GOTOFF(eax,PW_MF0344_F0285)]
174
175        paddd     xmm2,[GOTOFF(eax,PD_ONEHALF)]
176        paddd     xmm4,[GOTOFF(eax,PD_ONEHALF)]
177        psrad     xmm2,SCALEBITS
178        psrad     xmm4,SCALEBITS
179        paddd     xmm3,[GOTOFF(eax,PD_ONEHALF)]
180        paddd     xmm5,[GOTOFF(eax,PD_ONEHALF)]
181        psrad     xmm3,SCALEBITS
182        psrad     xmm5,SCALEBITS
183
184        packssdw  xmm2,xmm4     ; xmm2=CbE*-FIX(0.344)+CrE*FIX(0.285)
185        packssdw  xmm3,xmm5     ; xmm3=CbO*-FIX(0.344)+CrO*FIX(0.285)
186        psubw     xmm2,xmm6     ; xmm2=CbE*-FIX(0.344)+CrE*-FIX(0.714)=(G-Y)E
187        psubw     xmm3,xmm7     ; xmm3=CbO*-FIX(0.344)+CrO*-FIX(0.714)=(G-Y)O
188
189        movdqa    xmm5, XMMWORD [esi]   ; xmm5=Y(0123456789ABCDEF)
190
191        pcmpeqw   xmm4,xmm4
192        psrlw     xmm4,BYTE_BIT         ; xmm4={0xFF 0x00 0xFF 0x00 ..}
193        pand      xmm4,xmm5             ; xmm4=Y(02468ACE)=YE
194        psrlw     xmm5,BYTE_BIT         ; xmm5=Y(13579BDF)=YO
195
196        paddw     xmm0,xmm4             ; xmm0=((R-Y)E+YE)=RE=R(02468ACE)
197        paddw     xmm1,xmm5             ; xmm1=((R-Y)O+YO)=RO=R(13579BDF)
198        packuswb  xmm0,xmm0             ; xmm0=R(02468ACE********)
199        packuswb  xmm1,xmm1             ; xmm1=R(13579BDF********)
200
201        paddw     xmm2,xmm4             ; xmm2=((G-Y)E+YE)=GE=G(02468ACE)
202        paddw     xmm3,xmm5             ; xmm3=((G-Y)O+YO)=GO=G(13579BDF)
203        packuswb  xmm2,xmm2             ; xmm2=G(02468ACE********)
204        packuswb  xmm3,xmm3             ; xmm3=G(13579BDF********)
205
206        paddw     xmm4, XMMWORD [wk(0)] ; xmm4=(YE+(B-Y)E)=BE=B(02468ACE)
207        paddw     xmm5, XMMWORD [wk(1)] ; xmm5=(YO+(B-Y)O)=BO=B(13579BDF)
208        packuswb  xmm4,xmm4             ; xmm4=B(02468ACE********)
209        packuswb  xmm5,xmm5             ; xmm5=B(13579BDF********)
210
211%if RGB_PIXELSIZE == 3 ; ---------------
212
213        ; xmmA=(00 02 04 06 08 0A 0C 0E **), xmmB=(01 03 05 07 09 0B 0D 0F **)
214        ; xmmC=(10 12 14 16 18 1A 1C 1E **), xmmD=(11 13 15 17 19 1B 1D 1F **)
215        ; xmmE=(20 22 24 26 28 2A 2C 2E **), xmmF=(21 23 25 27 29 2B 2D 2F **)
216        ; xmmG=(** ** ** ** ** ** ** ** **), xmmH=(** ** ** ** ** ** ** ** **)
217
218        punpcklbw xmmA,xmmC     ; xmmA=(00 10 02 12 04 14 06 16 08 18 0A 1A 0C 1C 0E 1E)
219        punpcklbw xmmE,xmmB     ; xmmE=(20 01 22 03 24 05 26 07 28 09 2A 0B 2C 0D 2E 0F)
220        punpcklbw xmmD,xmmF     ; xmmD=(11 21 13 23 15 25 17 27 19 29 1B 2B 1D 2D 1F 2F)
221
222        movdqa    xmmG,xmmA
223        movdqa    xmmH,xmmA
224        punpcklwd xmmA,xmmE     ; xmmA=(00 10 20 01 02 12 22 03 04 14 24 05 06 16 26 07)
225        punpckhwd xmmG,xmmE     ; xmmG=(08 18 28 09 0A 1A 2A 0B 0C 1C 2C 0D 0E 1E 2E 0F)
226
227        psrldq    xmmH,2        ; xmmH=(02 12 04 14 06 16 08 18 0A 1A 0C 1C 0E 1E -- --)
228        psrldq    xmmE,2        ; xmmE=(22 03 24 05 26 07 28 09 2A 0B 2C 0D 2E 0F -- --)
229
230        movdqa    xmmC,xmmD
231        movdqa    xmmB,xmmD
232        punpcklwd xmmD,xmmH     ; xmmD=(11 21 02 12 13 23 04 14 15 25 06 16 17 27 08 18)
233        punpckhwd xmmC,xmmH     ; xmmC=(19 29 0A 1A 1B 2B 0C 1C 1D 2D 0E 1E 1F 2F -- --)
234
235        psrldq    xmmB,2        ; xmmB=(13 23 15 25 17 27 19 29 1B 2B 1D 2D 1F 2F -- --)
236
237        movdqa    xmmF,xmmE
238        punpcklwd xmmE,xmmB     ; xmmE=(22 03 13 23 24 05 15 25 26 07 17 27 28 09 19 29)
239        punpckhwd xmmF,xmmB     ; xmmF=(2A 0B 1B 2B 2C 0D 1D 2D 2E 0F 1F 2F -- -- -- --)
240
241        pshufd    xmmH,xmmA,0x4E; xmmH=(04 14 24 05 06 16 26 07 00 10 20 01 02 12 22 03)
242        movdqa    xmmB,xmmE
243        punpckldq xmmA,xmmD     ; xmmA=(00 10 20 01 11 21 02 12 02 12 22 03 13 23 04 14)
244        punpckldq xmmE,xmmH     ; xmmE=(22 03 13 23 04 14 24 05 24 05 15 25 06 16 26 07)
245        punpckhdq xmmD,xmmB     ; xmmD=(15 25 06 16 26 07 17 27 17 27 08 18 28 09 19 29)
246
247        pshufd    xmmH,xmmG,0x4E; xmmH=(0C 1C 2C 0D 0E 1E 2E 0F 08 18 28 09 0A 1A 2A 0B)
248        movdqa    xmmB,xmmF
249        punpckldq xmmG,xmmC     ; xmmG=(08 18 28 09 19 29 0A 1A 0A 1A 2A 0B 1B 2B 0C 1C)
250        punpckldq xmmF,xmmH     ; xmmF=(2A 0B 1B 2B 0C 1C 2C 0D 2C 0D 1D 2D 0E 1E 2E 0F)
251        punpckhdq xmmC,xmmB     ; xmmC=(1D 2D 0E 1E 2E 0F 1F 2F 1F 2F -- -- -- -- -- --)
252
253        punpcklqdq xmmA,xmmE    ; xmmA=(00 10 20 01 11 21 02 12 22 03 13 23 04 14 24 05)
254        punpcklqdq xmmD,xmmG    ; xmmD=(15 25 06 16 26 07 17 27 08 18 28 09 19 29 0A 1A)
255        punpcklqdq xmmF,xmmC    ; xmmF=(2A 0B 1B 2B 0C 1C 2C 0D 1D 2D 0E 1E 2E 0F 1F 2F)
256
257        cmp     ecx, byte SIZEOF_XMMWORD
258        jb      short .column_st32
259
260        test    edi, SIZEOF_XMMWORD-1
261        jnz     short .out1
262        ; --(aligned)-------------------
263        movntdq XMMWORD [edi+0*SIZEOF_XMMWORD], xmmA
264        movntdq XMMWORD [edi+1*SIZEOF_XMMWORD], xmmD
265        movntdq XMMWORD [edi+2*SIZEOF_XMMWORD], xmmF
266        jmp     short .out0
267.out1:  ; --(unaligned)-----------------
268        movdqu  XMMWORD [edi+0*SIZEOF_XMMWORD], xmmA
269        movdqu  XMMWORD [edi+1*SIZEOF_XMMWORD], xmmD
270        movdqu  XMMWORD [edi+2*SIZEOF_XMMWORD], xmmF
271.out0:
272        add     edi, byte RGB_PIXELSIZE*SIZEOF_XMMWORD  ; outptr
273        sub     ecx, byte SIZEOF_XMMWORD
274        jz      near .nextrow
275
276        add     esi, byte SIZEOF_XMMWORD        ; inptr0
277        add     ebx, byte SIZEOF_XMMWORD        ; inptr1
278        add     edx, byte SIZEOF_XMMWORD        ; inptr2
279        jmp     near .columnloop
280        alignx  16,7
281
282.column_st32:
283        lea     ecx, [ecx+ecx*2]                ; imul ecx, RGB_PIXELSIZE
284        cmp     ecx, byte 2*SIZEOF_XMMWORD
285        jb      short .column_st16
286        movdqu  XMMWORD [edi+0*SIZEOF_XMMWORD], xmmA
287        movdqu  XMMWORD [edi+1*SIZEOF_XMMWORD], xmmD
288        add     edi, byte 2*SIZEOF_XMMWORD      ; outptr
289        movdqa  xmmA,xmmF
290        sub     ecx, byte 2*SIZEOF_XMMWORD
291        jmp     short .column_st15
292.column_st16:
293        cmp     ecx, byte SIZEOF_XMMWORD
294        jb      short .column_st15
295        movdqu  XMMWORD [edi+0*SIZEOF_XMMWORD], xmmA
296        add     edi, byte SIZEOF_XMMWORD        ; outptr
297        movdqa  xmmA,xmmD
298        sub     ecx, byte SIZEOF_XMMWORD
299.column_st15:
300        ; Store the lower 8 bytes of xmmA to the output when it has enough
301        ; space.
302        cmp     ecx, byte SIZEOF_MMWORD
303        jb      short .column_st7
304        movq    XMM_MMWORD [edi], xmmA
305        add     edi, byte SIZEOF_MMWORD
306        sub     ecx, byte SIZEOF_MMWORD
307        psrldq  xmmA, SIZEOF_MMWORD
308.column_st7:
309        ; Store the lower 4 bytes of xmmA to the output when it has enough
310        ; space.
311        cmp     ecx, byte SIZEOF_DWORD
312        jb      short .column_st3
313        movd    XMM_DWORD [edi], xmmA
314        add     edi, byte SIZEOF_DWORD
315        sub     ecx, byte SIZEOF_DWORD
316        psrldq  xmmA, SIZEOF_DWORD
317.column_st3:
318        ; Store the lower 2 bytes of eax to the output when it has enough
319        ; space.
320        movd    eax, xmmA
321        cmp     ecx, byte SIZEOF_WORD
322        jb      short .column_st1
323        mov     WORD [edi], ax
324        add     edi, byte SIZEOF_WORD
325        sub     ecx, byte SIZEOF_WORD
326        shr     eax, 16
327.column_st1:
328        ; Store the lower 1 byte of eax to the output when it has enough
329        ; space.
330        test    ecx, ecx
331        jz      short .nextrow
332        mov     BYTE [edi], al
333
334%else ; RGB_PIXELSIZE == 4 ; -----------
335
336%ifdef RGBX_FILLER_0XFF
337        pcmpeqb   xmm6,xmm6             ; xmm6=XE=X(02468ACE********)
338        pcmpeqb   xmm7,xmm7             ; xmm7=XO=X(13579BDF********)
339%else
340        pxor      xmm6,xmm6             ; xmm6=XE=X(02468ACE********)
341        pxor      xmm7,xmm7             ; xmm7=XO=X(13579BDF********)
342%endif
343        ; xmmA=(00 02 04 06 08 0A 0C 0E **), xmmB=(01 03 05 07 09 0B 0D 0F **)
344        ; xmmC=(10 12 14 16 18 1A 1C 1E **), xmmD=(11 13 15 17 19 1B 1D 1F **)
345        ; xmmE=(20 22 24 26 28 2A 2C 2E **), xmmF=(21 23 25 27 29 2B 2D 2F **)
346        ; xmmG=(30 32 34 36 38 3A 3C 3E **), xmmH=(31 33 35 37 39 3B 3D 3F **)
347
348        punpcklbw xmmA,xmmC     ; xmmA=(00 10 02 12 04 14 06 16 08 18 0A 1A 0C 1C 0E 1E)
349        punpcklbw xmmE,xmmG     ; xmmE=(20 30 22 32 24 34 26 36 28 38 2A 3A 2C 3C 2E 3E)
350        punpcklbw xmmB,xmmD     ; xmmB=(01 11 03 13 05 15 07 17 09 19 0B 1B 0D 1D 0F 1F)
351        punpcklbw xmmF,xmmH     ; xmmF=(21 31 23 33 25 35 27 37 29 39 2B 3B 2D 3D 2F 3F)
352
353        movdqa    xmmC,xmmA
354        punpcklwd xmmA,xmmE     ; xmmA=(00 10 20 30 02 12 22 32 04 14 24 34 06 16 26 36)
355        punpckhwd xmmC,xmmE     ; xmmC=(08 18 28 38 0A 1A 2A 3A 0C 1C 2C 3C 0E 1E 2E 3E)
356        movdqa    xmmG,xmmB
357        punpcklwd xmmB,xmmF     ; xmmB=(01 11 21 31 03 13 23 33 05 15 25 35 07 17 27 37)
358        punpckhwd xmmG,xmmF     ; xmmG=(09 19 29 39 0B 1B 2B 3B 0D 1D 2D 3D 0F 1F 2F 3F)
359
360        movdqa    xmmD,xmmA
361        punpckldq xmmA,xmmB     ; xmmA=(00 10 20 30 01 11 21 31 02 12 22 32 03 13 23 33)
362        punpckhdq xmmD,xmmB     ; xmmD=(04 14 24 34 05 15 25 35 06 16 26 36 07 17 27 37)
363        movdqa    xmmH,xmmC
364        punpckldq xmmC,xmmG     ; xmmC=(08 18 28 38 09 19 29 39 0A 1A 2A 3A 0B 1B 2B 3B)
365        punpckhdq xmmH,xmmG     ; xmmH=(0C 1C 2C 3C 0D 1D 2D 3D 0E 1E 2E 3E 0F 1F 2F 3F)
366
367        cmp     ecx, byte SIZEOF_XMMWORD
368        jb      short .column_st32
369
370        test    edi, SIZEOF_XMMWORD-1
371        jnz     short .out1
372        ; --(aligned)-------------------
373        movntdq XMMWORD [edi+0*SIZEOF_XMMWORD], xmmA
374        movntdq XMMWORD [edi+1*SIZEOF_XMMWORD], xmmD
375        movntdq XMMWORD [edi+2*SIZEOF_XMMWORD], xmmC
376        movntdq XMMWORD [edi+3*SIZEOF_XMMWORD], xmmH
377        jmp     short .out0
378.out1:  ; --(unaligned)-----------------
379        movdqu  XMMWORD [edi+0*SIZEOF_XMMWORD], xmmA
380        movdqu  XMMWORD [edi+1*SIZEOF_XMMWORD], xmmD
381        movdqu  XMMWORD [edi+2*SIZEOF_XMMWORD], xmmC
382        movdqu  XMMWORD [edi+3*SIZEOF_XMMWORD], xmmH
383.out0:
384        add     edi, byte RGB_PIXELSIZE*SIZEOF_XMMWORD  ; outptr
385        sub     ecx, byte SIZEOF_XMMWORD
386        jz      near .nextrow
387
388        add     esi, byte SIZEOF_XMMWORD        ; inptr0
389        add     ebx, byte SIZEOF_XMMWORD        ; inptr1
390        add     edx, byte SIZEOF_XMMWORD        ; inptr2
391        jmp     near .columnloop
392        alignx  16,7
393
394.column_st32:
395        cmp     ecx, byte SIZEOF_XMMWORD/2
396        jb      short .column_st16
397        movdqu  XMMWORD [edi+0*SIZEOF_XMMWORD], xmmA
398        movdqu  XMMWORD [edi+1*SIZEOF_XMMWORD], xmmD
399        add     edi, byte 2*SIZEOF_XMMWORD      ; outptr
400        movdqa  xmmA,xmmC
401        movdqa  xmmD,xmmH
402        sub     ecx, byte SIZEOF_XMMWORD/2
403.column_st16:
404        cmp     ecx, byte SIZEOF_XMMWORD/4
405        jb      short .column_st15
406        movdqu  XMMWORD [edi+0*SIZEOF_XMMWORD], xmmA
407        add     edi, byte SIZEOF_XMMWORD        ; outptr
408        movdqa  xmmA,xmmD
409        sub     ecx, byte SIZEOF_XMMWORD/4
410.column_st15:
411        ; Store two pixels (8 bytes) of xmmA to the output when it has enough
412        ; space.
413        cmp     ecx, byte SIZEOF_XMMWORD/8
414        jb      short .column_st7
415        movq    XMM_MMWORD [edi], xmmA
416        add     edi, byte SIZEOF_XMMWORD/8*4
417        sub     ecx, byte SIZEOF_XMMWORD/8
418        psrldq  xmmA, SIZEOF_XMMWORD/8*4
419.column_st7:
420        ; Store one pixel (4 bytes) of xmmA to the output when it has enough
421        ; space.
422        test    ecx, ecx
423        jz      short .nextrow
424        movd    XMM_DWORD [edi], xmmA
425
426%endif ; RGB_PIXELSIZE ; ---------------
427
428        alignx  16,7
429
430.nextrow:
431        pop     ecx
432        pop     esi
433        pop     ebx
434        pop     edx
435        pop     edi
436        pop     eax
437
438        add     esi, byte SIZEOF_JSAMPROW
439        add     ebx, byte SIZEOF_JSAMPROW
440        add     edx, byte SIZEOF_JSAMPROW
441        add     edi, byte SIZEOF_JSAMPROW       ; output_buf
442        dec     eax                             ; num_rows
443        jg      near .rowloop
444
445        sfence          ; flush the write buffer
446
447.return:
448        pop     edi
449        pop     esi
450;       pop     edx             ; need not be preserved
451;       pop     ecx             ; need not be preserved
452        pop     ebx
453        mov     esp,ebp         ; esp <- aligned ebp
454        pop     esp             ; esp <- original ebp
455        pop     ebp
456        ret
457
458; For some reason, the OS X linker does not honor the request to align the
459; segment unless we do this.
460        align   16
461