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