summaryrefslogtreecommitdiff
path: root/media/libjpeg/simd/i386/jfdctint-sse2.asm
blob: 6f8e18cb9d052f3a3285c66b684e96ca5d974e74 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
;
; jfdctint.asm - accurate integer FDCT (SSE2)
;
; Copyright 2009 Pierre Ossman <ossman@cendio.se> for Cendio AB
; Copyright (C) 2016, 2020, D. R. Commander.
;
; Based on the 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 slower but more 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.

%include "jsimdext.inc"
%include "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      32
    GLOBAL_DATA(jconst_fdct_islow_sse2)

EXTN(jconst_fdct_islow_sse2):

PW_F130_F054   times 4 dw  (F_0_541 + F_0_765),  F_0_541
PW_F054_MF130  times 4 dw  F_0_541, (F_0_541 - F_1_847)
PW_MF078_F117  times 4 dw  (F_1_175 - F_1_961),  F_1_175
PW_F117_F078   times 4 dw  F_1_175, (F_1_175 - F_0_390)
PW_MF060_MF089 times 4 dw  (F_0_298 - F_0_899), -F_0_899
PW_MF089_F060  times 4 dw -F_0_899, (F_1_501 - F_0_899)
PW_MF050_MF256 times 4 dw  (F_2_053 - F_2_562), -F_2_562
PW_MF256_F050  times 4 dw -F_2_562, (F_3_072 - F_2_562)
PD_DESCALE_P1  times 4 dd  1 << (DESCALE_P1 - 1)
PD_DESCALE_P2  times 4 dd  1 << (DESCALE_P2 - 1)
PW_DESCALE_P2X times 8 dw  1 << (PASS1_BITS - 1)

    alignz      32

; --------------------------------------------------------------------------
    SECTION     SEG_TEXT
    BITS        32
;
; Perform the forward DCT on one block of samples.
;
; GLOBAL(void)
; jsimd_fdct_islow_sse2(DCTELEM *data)
;

%define data(b)       (b) + 8           ; DCTELEM *data

%define original_ebp  ebp + 0
%define wk(i)         ebp - (WK_NUM - (i)) * SIZEOF_XMMWORD
                                        ; xmmword wk[WK_NUM]
%define WK_NUM        6

    align       32
    GLOBAL_FUNCTION(jsimd_fdct_islow_sse2)

EXTN(jsimd_fdct_islow_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     ebx
;   push        ecx                     ; unused
;   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 *)

    movdqa      xmm0, XMMWORD [XMMBLOCK(0,0,edx,SIZEOF_DCTELEM)]
    movdqa      xmm1, XMMWORD [XMMBLOCK(1,0,edx,SIZEOF_DCTELEM)]
    movdqa      xmm2, XMMWORD [XMMBLOCK(2,0,edx,SIZEOF_DCTELEM)]
    movdqa      xmm3, XMMWORD [XMMBLOCK(3,0,edx,SIZEOF_DCTELEM)]

    ; xmm0=(00 01 02 03 04 05 06 07), xmm2=(20 21 22 23 24 25 26 27)
    ; xmm1=(10 11 12 13 14 15 16 17), xmm3=(30 31 32 33 34 35 36 37)

    movdqa      xmm4, xmm0              ; transpose coefficients(phase 1)
    punpcklwd   xmm0, xmm1              ; xmm0=(00 10 01 11 02 12 03 13)
    punpckhwd   xmm4, xmm1              ; xmm4=(04 14 05 15 06 16 07 17)
    movdqa      xmm5, xmm2              ; transpose coefficients(phase 1)
    punpcklwd   xmm2, xmm3              ; xmm2=(20 30 21 31 22 32 23 33)
    punpckhwd   xmm5, xmm3              ; xmm5=(24 34 25 35 26 36 27 37)

    movdqa      xmm6, XMMWORD [XMMBLOCK(4,0,edx,SIZEOF_DCTELEM)]
    movdqa      xmm7, XMMWORD [XMMBLOCK(5,0,edx,SIZEOF_DCTELEM)]
    movdqa      xmm1, XMMWORD [XMMBLOCK(6,0,edx,SIZEOF_DCTELEM)]
    movdqa      xmm3, XMMWORD [XMMBLOCK(7,0,edx,SIZEOF_DCTELEM)]

    ; xmm6=( 4 12 20 28 36 44 52 60), xmm1=( 6 14 22 30 38 46 54 62)
    ; xmm7=( 5 13 21 29 37 45 53 61), xmm3=( 7 15 23 31 39 47 55 63)

    movdqa      XMMWORD [wk(0)], xmm2   ; wk(0)=(20 30 21 31 22 32 23 33)
    movdqa      XMMWORD [wk(1)], xmm5   ; wk(1)=(24 34 25 35 26 36 27 37)

    movdqa      xmm2, xmm6              ; transpose coefficients(phase 1)
    punpcklwd   xmm6, xmm7              ; xmm6=(40 50 41 51 42 52 43 53)
    punpckhwd   xmm2, xmm7              ; xmm2=(44 54 45 55 46 56 47 57)
    movdqa      xmm5, xmm1              ; transpose coefficients(phase 1)
    punpcklwd   xmm1, xmm3              ; xmm1=(60 70 61 71 62 72 63 73)
    punpckhwd   xmm5, xmm3              ; xmm5=(64 74 65 75 66 76 67 77)

    movdqa      xmm7, xmm6              ; transpose coefficients(phase 2)
    punpckldq   xmm6, xmm1              ; xmm6=(40 50 60 70 41 51 61 71)
    punpckhdq   xmm7, xmm1              ; xmm7=(42 52 62 72 43 53 63 73)
    movdqa      xmm3, xmm2              ; transpose coefficients(phase 2)
    punpckldq   xmm2, xmm5              ; xmm2=(44 54 64 74 45 55 65 75)
    punpckhdq   xmm3, xmm5              ; xmm3=(46 56 66 76 47 57 67 77)

    movdqa      xmm1, XMMWORD [wk(0)]   ; xmm1=(20 30 21 31 22 32 23 33)
    movdqa      xmm5, XMMWORD [wk(1)]   ; xmm5=(24 34 25 35 26 36 27 37)
    movdqa      XMMWORD [wk(2)], xmm7   ; wk(2)=(42 52 62 72 43 53 63 73)
    movdqa      XMMWORD [wk(3)], xmm2   ; wk(3)=(44 54 64 74 45 55 65 75)

    movdqa      xmm7, xmm0              ; transpose coefficients(phase 2)
    punpckldq   xmm0, xmm1              ; xmm0=(00 10 20 30 01 11 21 31)
    punpckhdq   xmm7, xmm1              ; xmm7=(02 12 22 32 03 13 23 33)
    movdqa      xmm2, xmm4              ; transpose coefficients(phase 2)
    punpckldq   xmm4, xmm5              ; xmm4=(04 14 24 34 05 15 25 35)
    punpckhdq   xmm2, xmm5              ; xmm2=(06 16 26 36 07 17 27 37)

    movdqa      xmm1, xmm0              ; transpose coefficients(phase 3)
    punpcklqdq  xmm0, xmm6              ; xmm0=(00 10 20 30 40 50 60 70)=data0
    punpckhqdq  xmm1, xmm6              ; xmm1=(01 11 21 31 41 51 61 71)=data1
    movdqa      xmm5, xmm2              ; transpose coefficients(phase 3)
    punpcklqdq  xmm2, xmm3              ; xmm2=(06 16 26 36 46 56 66 76)=data6
    punpckhqdq  xmm5, xmm3              ; xmm5=(07 17 27 37 47 57 67 77)=data7

    movdqa      xmm6, xmm1
    movdqa      xmm3, xmm0
    psubw       xmm1, xmm2              ; xmm1=data1-data6=tmp6
    psubw       xmm0, xmm5              ; xmm0=data0-data7=tmp7
    paddw       xmm6, xmm2              ; xmm6=data1+data6=tmp1
    paddw       xmm3, xmm5              ; xmm3=data0+data7=tmp0

    movdqa      xmm2, XMMWORD [wk(2)]   ; xmm2=(42 52 62 72 43 53 63 73)
    movdqa      xmm5, XMMWORD [wk(3)]   ; xmm5=(44 54 64 74 45 55 65 75)
    movdqa      XMMWORD [wk(0)], xmm1   ; wk(0)=tmp6
    movdqa      XMMWORD [wk(1)], xmm0   ; wk(1)=tmp7

    movdqa      xmm1, xmm7              ; transpose coefficients(phase 3)
    punpcklqdq  xmm7, xmm2              ; xmm7=(02 12 22 32 42 52 62 72)=data2
    punpckhqdq  xmm1, xmm2              ; xmm1=(03 13 23 33 43 53 63 73)=data3
    movdqa      xmm0, xmm4              ; transpose coefficients(phase 3)
    punpcklqdq  xmm4, xmm5              ; xmm4=(04 14 24 34 44 54 64 74)=data4
    punpckhqdq  xmm0, xmm5              ; xmm0=(05 15 25 35 45 55 65 75)=data5

    movdqa      xmm2, xmm1
    movdqa      xmm5, xmm7
    paddw       xmm1, xmm4              ; xmm1=data3+data4=tmp3
    paddw       xmm7, xmm0              ; xmm7=data2+data5=tmp2
    psubw       xmm2, xmm4              ; xmm2=data3-data4=tmp4
    psubw       xmm5, xmm0              ; xmm5=data2-data5=tmp5

    ; -- Even part

    movdqa      xmm4, xmm3
    movdqa      xmm0, xmm6
    paddw       xmm3, xmm1              ; xmm3=tmp10
    paddw       xmm6, xmm7              ; xmm6=tmp11
    psubw       xmm4, xmm1              ; xmm4=tmp13
    psubw       xmm0, xmm7              ; xmm0=tmp12

    movdqa      xmm1, xmm3
    paddw       xmm3, xmm6              ; xmm3=tmp10+tmp11
    psubw       xmm1, xmm6              ; xmm1=tmp10-tmp11

    psllw       xmm3, PASS1_BITS        ; xmm3=data0
    psllw       xmm1, PASS1_BITS        ; xmm1=data4

    movdqa      XMMWORD [wk(2)], xmm3   ; wk(2)=data0
    movdqa      XMMWORD [wk(3)], xmm1   ; wk(3)=data4

    ; (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);

    movdqa      xmm7, xmm4              ; xmm4=tmp13
    movdqa      xmm6, xmm4
    punpcklwd   xmm7, xmm0              ; xmm0=tmp12
    punpckhwd   xmm6, xmm0
    movdqa      xmm4, xmm7
    movdqa      xmm0, xmm6
    pmaddwd     xmm7, [GOTOFF(ebx,PW_F130_F054)]   ; xmm7=data2L
    pmaddwd     xmm6, [GOTOFF(ebx,PW_F130_F054)]   ; xmm6=data2H
    pmaddwd     xmm4, [GOTOFF(ebx,PW_F054_MF130)]  ; xmm4=data6L
    pmaddwd     xmm0, [GOTOFF(ebx,PW_F054_MF130)]  ; xmm0=data6H

    paddd       xmm7, [GOTOFF(ebx,PD_DESCALE_P1)]
    paddd       xmm6, [GOTOFF(ebx,PD_DESCALE_P1)]
    psrad       xmm7, DESCALE_P1
    psrad       xmm6, DESCALE_P1
    paddd       xmm4, [GOTOFF(ebx,PD_DESCALE_P1)]
    paddd       xmm0, [GOTOFF(ebx,PD_DESCALE_P1)]
    psrad       xmm4, DESCALE_P1
    psrad       xmm0, DESCALE_P1

    packssdw    xmm7, xmm6              ; xmm7=data2
    packssdw    xmm4, xmm0              ; xmm4=data6

    movdqa      XMMWORD [wk(4)], xmm7   ; wk(4)=data2
    movdqa      XMMWORD [wk(5)], xmm4   ; wk(5)=data6

    ; -- Odd part

    movdqa      xmm3, XMMWORD [wk(0)]   ; xmm3=tmp6
    movdqa      xmm1, XMMWORD [wk(1)]   ; xmm1=tmp7

    movdqa      xmm6, xmm2              ; xmm2=tmp4
    movdqa      xmm0, xmm5              ; xmm5=tmp5
    paddw       xmm6, xmm3              ; xmm6=z3
    paddw       xmm0, xmm1              ; xmm0=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);

    movdqa      xmm7, xmm6
    movdqa      xmm4, xmm6
    punpcklwd   xmm7, xmm0
    punpckhwd   xmm4, xmm0
    movdqa      xmm6, xmm7
    movdqa      xmm0, xmm4
    pmaddwd     xmm7, [GOTOFF(ebx,PW_MF078_F117)]  ; xmm7=z3L
    pmaddwd     xmm4, [GOTOFF(ebx,PW_MF078_F117)]  ; xmm4=z3H
    pmaddwd     xmm6, [GOTOFF(ebx,PW_F117_F078)]   ; xmm6=z4L
    pmaddwd     xmm0, [GOTOFF(ebx,PW_F117_F078)]   ; xmm0=z4H

    movdqa      XMMWORD [wk(0)], xmm7   ; wk(0)=z3L
    movdqa      XMMWORD [wk(1)], xmm4   ; 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;

    movdqa      xmm7, xmm2
    movdqa      xmm4, xmm2
    punpcklwd   xmm7, xmm1
    punpckhwd   xmm4, xmm1
    movdqa      xmm2, xmm7
    movdqa      xmm1, xmm4
    pmaddwd     xmm7, [GOTOFF(ebx,PW_MF060_MF089)]  ; xmm7=tmp4L
    pmaddwd     xmm4, [GOTOFF(ebx,PW_MF060_MF089)]  ; xmm4=tmp4H
    pmaddwd     xmm2, [GOTOFF(ebx,PW_MF089_F060)]   ; xmm2=tmp7L
    pmaddwd     xmm1, [GOTOFF(ebx,PW_MF089_F060)]   ; xmm1=tmp7H

    paddd       xmm7, XMMWORD [wk(0)]   ; xmm7=data7L
    paddd       xmm4, XMMWORD [wk(1)]   ; xmm4=data7H
    paddd       xmm2, xmm6              ; xmm2=data1L
    paddd       xmm1, xmm0              ; xmm1=data1H

    paddd       xmm7, [GOTOFF(ebx,PD_DESCALE_P1)]
    paddd       xmm4, [GOTOFF(ebx,PD_DESCALE_P1)]
    psrad       xmm7, DESCALE_P1
    psrad       xmm4, DESCALE_P1
    paddd       xmm2, [GOTOFF(ebx,PD_DESCALE_P1)]
    paddd       xmm1, [GOTOFF(ebx,PD_DESCALE_P1)]
    psrad       xmm2, DESCALE_P1
    psrad       xmm1, DESCALE_P1

    packssdw    xmm7, xmm4              ; xmm7=data7
    packssdw    xmm2, xmm1              ; xmm2=data1

    movdqa      xmm4, xmm5
    movdqa      xmm1, xmm5
    punpcklwd   xmm4, xmm3
    punpckhwd   xmm1, xmm3
    movdqa      xmm5, xmm4
    movdqa      xmm3, xmm1
    pmaddwd     xmm4, [GOTOFF(ebx,PW_MF050_MF256)]  ; xmm4=tmp5L
    pmaddwd     xmm1, [GOTOFF(ebx,PW_MF050_MF256)]  ; xmm1=tmp5H
    pmaddwd     xmm5, [GOTOFF(ebx,PW_MF256_F050)]   ; xmm5=tmp6L
    pmaddwd     xmm3, [GOTOFF(ebx,PW_MF256_F050)]   ; xmm3=tmp6H

    paddd       xmm4, xmm6              ; xmm4=data5L
    paddd       xmm1, xmm0              ; xmm1=data5H
    paddd       xmm5, XMMWORD [wk(0)]   ; xmm5=data3L
    paddd       xmm3, XMMWORD [wk(1)]   ; xmm3=data3H

    paddd       xmm4, [GOTOFF(ebx,PD_DESCALE_P1)]
    paddd       xmm1, [GOTOFF(ebx,PD_DESCALE_P1)]
    psrad       xmm4, DESCALE_P1
    psrad       xmm1, DESCALE_P1
    paddd       xmm5, [GOTOFF(ebx,PD_DESCALE_P1)]
    paddd       xmm3, [GOTOFF(ebx,PD_DESCALE_P1)]
    psrad       xmm5, DESCALE_P1
    psrad       xmm3, DESCALE_P1

    packssdw    xmm4, xmm1              ; xmm4=data5
    packssdw    xmm5, xmm3              ; xmm5=data3

    ; ---- Pass 2: process columns.

;   mov         edx, POINTER [data(eax)]  ; (DCTELEM *)

    movdqa      xmm6, XMMWORD [wk(2)]   ; xmm6=col0
    movdqa      xmm0, XMMWORD [wk(4)]   ; xmm0=col2

    ; xmm6=(00 10 20 30 40 50 60 70), xmm0=(02 12 22 32 42 52 62 72)
    ; xmm2=(01 11 21 31 41 51 61 71), xmm5=(03 13 23 33 43 53 63 73)

    movdqa      xmm1, xmm6              ; transpose coefficients(phase 1)
    punpcklwd   xmm6, xmm2              ; xmm6=(00 01 10 11 20 21 30 31)
    punpckhwd   xmm1, xmm2              ; xmm1=(40 41 50 51 60 61 70 71)
    movdqa      xmm3, xmm0              ; transpose coefficients(phase 1)
    punpcklwd   xmm0, xmm5              ; xmm0=(02 03 12 13 22 23 32 33)
    punpckhwd   xmm3, xmm5              ; xmm3=(42 43 52 53 62 63 72 73)

    movdqa      xmm2, XMMWORD [wk(3)]   ; xmm2=col4
    movdqa      xmm5, XMMWORD [wk(5)]   ; xmm5=col6

    ; xmm2=(04 14 24 34 44 54 64 74), xmm5=(06 16 26 36 46 56 66 76)
    ; xmm4=(05 15 25 35 45 55 65 75), xmm7=(07 17 27 37 47 57 67 77)

    movdqa      XMMWORD [wk(0)], xmm0   ; wk(0)=(02 03 12 13 22 23 32 33)
    movdqa      XMMWORD [wk(1)], xmm3   ; wk(1)=(42 43 52 53 62 63 72 73)

    movdqa      xmm0, xmm2              ; transpose coefficients(phase 1)
    punpcklwd   xmm2, xmm4              ; xmm2=(04 05 14 15 24 25 34 35)
    punpckhwd   xmm0, xmm4              ; xmm0=(44 45 54 55 64 65 74 75)
    movdqa      xmm3, xmm5              ; transpose coefficients(phase 1)
    punpcklwd   xmm5, xmm7              ; xmm5=(06 07 16 17 26 27 36 37)
    punpckhwd   xmm3, xmm7              ; xmm3=(46 47 56 57 66 67 76 77)

    movdqa      xmm4, xmm2              ; transpose coefficients(phase 2)
    punpckldq   xmm2, xmm5              ; xmm2=(04 05 06 07 14 15 16 17)
    punpckhdq   xmm4, xmm5              ; xmm4=(24 25 26 27 34 35 36 37)
    movdqa      xmm7, xmm0              ; transpose coefficients(phase 2)
    punpckldq   xmm0, xmm3              ; xmm0=(44 45 46 47 54 55 56 57)
    punpckhdq   xmm7, xmm3              ; xmm7=(64 65 66 67 74 75 76 77)

    movdqa      xmm5, XMMWORD [wk(0)]   ; xmm5=(02 03 12 13 22 23 32 33)
    movdqa      xmm3, XMMWORD [wk(1)]   ; xmm3=(42 43 52 53 62 63 72 73)
    movdqa      XMMWORD [wk(2)], xmm4   ; wk(2)=(24 25 26 27 34 35 36 37)
    movdqa      XMMWORD [wk(3)], xmm0   ; wk(3)=(44 45 46 47 54 55 56 57)

    movdqa      xmm4, xmm6              ; transpose coefficients(phase 2)
    punpckldq   xmm6, xmm5              ; xmm6=(00 01 02 03 10 11 12 13)
    punpckhdq   xmm4, xmm5              ; xmm4=(20 21 22 23 30 31 32 33)
    movdqa      xmm0, xmm1              ; transpose coefficients(phase 2)
    punpckldq   xmm1, xmm3              ; xmm1=(40 41 42 43 50 51 52 53)
    punpckhdq   xmm0, xmm3              ; xmm0=(60 61 62 63 70 71 72 73)

    movdqa      xmm5, xmm6              ; transpose coefficients(phase 3)
    punpcklqdq  xmm6, xmm2              ; xmm6=(00 01 02 03 04 05 06 07)=data0
    punpckhqdq  xmm5, xmm2              ; xmm5=(10 11 12 13 14 15 16 17)=data1
    movdqa      xmm3, xmm0              ; transpose coefficients(phase 3)
    punpcklqdq  xmm0, xmm7              ; xmm0=(60 61 62 63 64 65 66 67)=data6
    punpckhqdq  xmm3, xmm7              ; xmm3=(70 71 72 73 74 75 76 77)=data7

    movdqa      xmm2, xmm5
    movdqa      xmm7, xmm6
    psubw       xmm5, xmm0              ; xmm5=data1-data6=tmp6
    psubw       xmm6, xmm3              ; xmm6=data0-data7=tmp7
    paddw       xmm2, xmm0              ; xmm2=data1+data6=tmp1
    paddw       xmm7, xmm3              ; xmm7=data0+data7=tmp0

    movdqa      xmm0, XMMWORD [wk(2)]   ; xmm0=(24 25 26 27 34 35 36 37)
    movdqa      xmm3, XMMWORD [wk(3)]   ; xmm3=(44 45 46 47 54 55 56 57)
    movdqa      XMMWORD [wk(0)], xmm5   ; wk(0)=tmp6
    movdqa      XMMWORD [wk(1)], xmm6   ; wk(1)=tmp7

    movdqa      xmm5, xmm4              ; transpose coefficients(phase 3)
    punpcklqdq  xmm4, xmm0              ; xmm4=(20 21 22 23 24 25 26 27)=data2
    punpckhqdq  xmm5, xmm0              ; xmm5=(30 31 32 33 34 35 36 37)=data3
    movdqa      xmm6, xmm1              ; transpose coefficients(phase 3)
    punpcklqdq  xmm1, xmm3              ; xmm1=(40 41 42 43 44 45 46 47)=data4
    punpckhqdq  xmm6, xmm3              ; xmm6=(50 51 52 53 54 55 56 57)=data5

    movdqa      xmm0, xmm5
    movdqa      xmm3, xmm4
    paddw       xmm5, xmm1              ; xmm5=data3+data4=tmp3
    paddw       xmm4, xmm6              ; xmm4=data2+data5=tmp2
    psubw       xmm0, xmm1              ; xmm0=data3-data4=tmp4
    psubw       xmm3, xmm6              ; xmm3=data2-data5=tmp5

    ; -- Even part

    movdqa      xmm1, xmm7
    movdqa      xmm6, xmm2
    paddw       xmm7, xmm5              ; xmm7=tmp10
    paddw       xmm2, xmm4              ; xmm2=tmp11
    psubw       xmm1, xmm5              ; xmm1=tmp13
    psubw       xmm6, xmm4              ; xmm6=tmp12

    movdqa      xmm5, xmm7
    paddw       xmm7, xmm2              ; xmm7=tmp10+tmp11
    psubw       xmm5, xmm2              ; xmm5=tmp10-tmp11

    paddw       xmm7, [GOTOFF(ebx,PW_DESCALE_P2X)]
    paddw       xmm5, [GOTOFF(ebx,PW_DESCALE_P2X)]
    psraw       xmm7, PASS1_BITS        ; xmm7=data0
    psraw       xmm5, PASS1_BITS        ; xmm5=data4

    movdqa      XMMWORD [XMMBLOCK(0,0,edx,SIZEOF_DCTELEM)], xmm7
    movdqa      XMMWORD [XMMBLOCK(4,0,edx,SIZEOF_DCTELEM)], xmm5

    ; (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);

    movdqa      xmm4, xmm1              ; xmm1=tmp13
    movdqa      xmm2, xmm1
    punpcklwd   xmm4, xmm6              ; xmm6=tmp12
    punpckhwd   xmm2, xmm6
    movdqa      xmm1, xmm4
    movdqa      xmm6, xmm2
    pmaddwd     xmm4, [GOTOFF(ebx,PW_F130_F054)]   ; xmm4=data2L
    pmaddwd     xmm2, [GOTOFF(ebx,PW_F130_F054)]   ; xmm2=data2H
    pmaddwd     xmm1, [GOTOFF(ebx,PW_F054_MF130)]  ; xmm1=data6L
    pmaddwd     xmm6, [GOTOFF(ebx,PW_F054_MF130)]  ; xmm6=data6H

    paddd       xmm4, [GOTOFF(ebx,PD_DESCALE_P2)]
    paddd       xmm2, [GOTOFF(ebx,PD_DESCALE_P2)]
    psrad       xmm4, DESCALE_P2
    psrad       xmm2, DESCALE_P2
    paddd       xmm1, [GOTOFF(ebx,PD_DESCALE_P2)]
    paddd       xmm6, [GOTOFF(ebx,PD_DESCALE_P2)]
    psrad       xmm1, DESCALE_P2
    psrad       xmm6, DESCALE_P2

    packssdw    xmm4, xmm2              ; xmm4=data2
    packssdw    xmm1, xmm6              ; xmm1=data6

    movdqa      XMMWORD [XMMBLOCK(2,0,edx,SIZEOF_DCTELEM)], xmm4
    movdqa      XMMWORD [XMMBLOCK(6,0,edx,SIZEOF_DCTELEM)], xmm1

    ; -- Odd part

    movdqa      xmm7, XMMWORD [wk(0)]   ; xmm7=tmp6
    movdqa      xmm5, XMMWORD [wk(1)]   ; xmm5=tmp7

    movdqa      xmm2, xmm0              ; xmm0=tmp4
    movdqa      xmm6, xmm3              ; xmm3=tmp5
    paddw       xmm2, xmm7              ; xmm2=z3
    paddw       xmm6, xmm5              ; xmm6=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);

    movdqa      xmm4, xmm2
    movdqa      xmm1, xmm2
    punpcklwd   xmm4, xmm6
    punpckhwd   xmm1, xmm6
    movdqa      xmm2, xmm4
    movdqa      xmm6, xmm1
    pmaddwd     xmm4, [GOTOFF(ebx,PW_MF078_F117)]  ; xmm4=z3L
    pmaddwd     xmm1, [GOTOFF(ebx,PW_MF078_F117)]  ; xmm1=z3H
    pmaddwd     xmm2, [GOTOFF(ebx,PW_F117_F078)]   ; xmm2=z4L
    pmaddwd     xmm6, [GOTOFF(ebx,PW_F117_F078)]   ; xmm6=z4H

    movdqa      XMMWORD [wk(0)], xmm4   ; wk(0)=z3L
    movdqa      XMMWORD [wk(1)], xmm1   ; 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;

    movdqa      xmm4, xmm0
    movdqa      xmm1, xmm0
    punpcklwd   xmm4, xmm5
    punpckhwd   xmm1, xmm5
    movdqa      xmm0, xmm4
    movdqa      xmm5, xmm1
    pmaddwd     xmm4, [GOTOFF(ebx,PW_MF060_MF089)]  ; xmm4=tmp4L
    pmaddwd     xmm1, [GOTOFF(ebx,PW_MF060_MF089)]  ; xmm1=tmp4H
    pmaddwd     xmm0, [GOTOFF(ebx,PW_MF089_F060)]   ; xmm0=tmp7L
    pmaddwd     xmm5, [GOTOFF(ebx,PW_MF089_F060)]   ; xmm5=tmp7H

    paddd       xmm4,  XMMWORD [wk(0)]  ; xmm4=data7L
    paddd       xmm1,  XMMWORD [wk(1)]  ; xmm1=data7H
    paddd       xmm0, xmm2              ; xmm0=data1L
    paddd       xmm5, xmm6              ; xmm5=data1H

    paddd       xmm4, [GOTOFF(ebx,PD_DESCALE_P2)]
    paddd       xmm1, [GOTOFF(ebx,PD_DESCALE_P2)]
    psrad       xmm4, DESCALE_P2
    psrad       xmm1, DESCALE_P2
    paddd       xmm0, [GOTOFF(ebx,PD_DESCALE_P2)]
    paddd       xmm5, [GOTOFF(ebx,PD_DESCALE_P2)]
    psrad       xmm0, DESCALE_P2
    psrad       xmm5, DESCALE_P2

    packssdw    xmm4, xmm1              ; xmm4=data7
    packssdw    xmm0, xmm5              ; xmm0=data1

    movdqa      XMMWORD [XMMBLOCK(7,0,edx,SIZEOF_DCTELEM)], xmm4
    movdqa      XMMWORD [XMMBLOCK(1,0,edx,SIZEOF_DCTELEM)], xmm0

    movdqa      xmm1, xmm3
    movdqa      xmm5, xmm3
    punpcklwd   xmm1, xmm7
    punpckhwd   xmm5, xmm7
    movdqa      xmm3, xmm1
    movdqa      xmm7, xmm5
    pmaddwd     xmm1, [GOTOFF(ebx,PW_MF050_MF256)]  ; xmm1=tmp5L
    pmaddwd     xmm5, [GOTOFF(ebx,PW_MF050_MF256)]  ; xmm5=tmp5H
    pmaddwd     xmm3, [GOTOFF(ebx,PW_MF256_F050)]   ; xmm3=tmp6L
    pmaddwd     xmm7, [GOTOFF(ebx,PW_MF256_F050)]   ; xmm7=tmp6H

    paddd       xmm1, xmm2              ; xmm1=data5L
    paddd       xmm5, xmm6              ; xmm5=data5H
    paddd       xmm3, XMMWORD [wk(0)]   ; xmm3=data3L
    paddd       xmm7, XMMWORD [wk(1)]   ; xmm7=data3H

    paddd       xmm1, [GOTOFF(ebx,PD_DESCALE_P2)]
    paddd       xmm5, [GOTOFF(ebx,PD_DESCALE_P2)]
    psrad       xmm1, DESCALE_P2
    psrad       xmm5, DESCALE_P2
    paddd       xmm3, [GOTOFF(ebx,PD_DESCALE_P2)]
    paddd       xmm7, [GOTOFF(ebx,PD_DESCALE_P2)]
    psrad       xmm3, DESCALE_P2
    psrad       xmm7, DESCALE_P2

    packssdw    xmm1, xmm5              ; xmm1=data5
    packssdw    xmm3, xmm7              ; xmm3=data3

    movdqa      XMMWORD [XMMBLOCK(5,0,edx,SIZEOF_DCTELEM)], xmm1
    movdqa      XMMWORD [XMMBLOCK(3,0,edx,SIZEOF_DCTELEM)], xmm3

;   pop         edi                     ; unused
;   pop         esi                     ; unused
;   pop         edx                     ; need not be preserved
;   pop         ecx                     ; unused
    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