aboutsummaryrefslogtreecommitdiffstats
path: root/libavcodec/arm/simple_idct_armv6.S
blob: f95c20d29531230ea5c4845074c4d829b3fdd6e9 (plain) (blame)
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
/*
 * Simple IDCT
 *
 * Copyright (c) 2001 Michael Niedermayer <michaelni@gmx.at>
 * Copyright (c) 2007 Mans Rullgard <mans@mansr.com>
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include "libavutil/arm/asm.S"

#define W1  22725   /* cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5 */
#define W2  21407   /* cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5 */
#define W3  19266   /* cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5 */
#define W4  16383   /* cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5 */
#define W5  12873   /* cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5 */
#define W6  8867    /* cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5 */
#define W7  4520    /* cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5 */
#define ROW_SHIFT 11
#define COL_SHIFT 20

#define W13 (W1 | (W3 << 16))
#define W26 (W2 | (W6 << 16))
#define W42 (W4 | (W2 << 16))
#define W42n (-W4&0xffff | (-W2 << 16))
#define W46 (W4 | (W6 << 16))
#define W57 (W5 | (W7 << 16))

/*
  Compute partial IDCT of single row.
  shift = left-shift amount
  r0 = source address
  r2 = row[2,0] <= 2 cycles
  r3 = row[3,1]
  ip = w42      <= 2 cycles

  Output in registers r4--r11
*/
        .macro idct_row shift
        ldr    lr, =W46              /* lr  = W4 | (W6 << 16) */
        mov    r1, #(1<<(\shift-1))
        smlad  r4, r2, ip, r1
        smlsd  r7, r2, ip, r1
        ldr    ip, =W13              /* ip  = W1 | (W3 << 16) */
        ldr    r10,=W57              /* r10 = W5 | (W7 << 16) */
        smlad  r5, r2, lr, r1
        smlsd  r6, r2, lr, r1

        smuad  r8, r3, ip            /* r8  =  B0 = W1*row[1] + W3*row[3] */
        smusdx r11,r3, r10           /* r11 =  B3 = W7*row[1] - W5*row[3] */
        ldr    lr, [r0, #12]         /* lr  =  row[7,5] */
        pkhtb  r2, ip, r10,asr #16   /* r3  =  W7 | (W3 << 16) */
        pkhbt  r1, ip, r10,lsl #16   /* r1  =  W1 | (W5 << 16) */
        smusdx r9, r2, r3            /* r9  = -B1 = W7*row[3] - W3*row[1] */
        smlad  r8, lr, r10,r8        /* B0  +=      W5*row[5] + W7*row[7] */
        smusdx r10,r3, r1            /* r10 =  B2 = W5*row[1] - W1*row[3] */

        ldr    r3, =W42n             /* r3 =  -W4 | (-W2 << 16) */
        smlad  r10,lr, r2, r10       /* B2 +=  W7*row[5] + W3*row[7] */
        ldr    r2, [r0, #4]          /* r2 =   row[6,4] */
        smlsdx r11,lr, ip, r11       /* B3 +=  W3*row[5] - W1*row[7] */
        ldr    ip, =W46              /* ip =   W4 | (W6 << 16) */
        smlad  r9, lr, r1, r9        /* B1 -=  W1*row[5] + W5*row[7] */

        smlad  r5, r2, r3, r5        /* A1 += -W4*row[4] - W2*row[6] */
        smlsd  r6, r2, r3, r6        /* A2 += -W4*row[4] + W2*row[6] */
        smlad  r4, r2, ip, r4        /* A0 +=  W4*row[4] + W6*row[6] */
        smlsd  r7, r2, ip, r7        /* A3 +=  W4*row[4] - W6*row[6] */
        .endm

/*
  Compute partial IDCT of half row.
  shift = left-shift amount
  r2 = row[2,0]
  r3 = row[3,1]
  ip = w42

  Output in registers r4--r11
*/
        .macro idct_row4 shift
        ldr    lr, =W46              /* lr =  W4 | (W6 << 16) */
        ldr    r10,=W57              /* r10 = W5 | (W7 << 16) */
        mov    r1, #(1<<(\shift-1))
        smlad  r4, r2, ip, r1
        smlsd  r7, r2, ip, r1
        ldr    ip, =W13              /* ip =  W1 | (W3 << 16) */
        smlad  r5, r2, lr, r1
        smlsd  r6, r2, lr, r1
        smusdx r11,r3, r10           /* r11 =  B3 = W7*row[1] - W5*row[3] */
        smuad  r8, r3, ip            /* r8  =  B0 = W1*row[1] + W3*row[3] */
        pkhtb  r2, ip, r10,asr #16   /* r3  =  W7 | (W3 << 16) */
        pkhbt  r1, ip, r10,lsl #16   /* r1  =  W1 | (W5 << 16) */
        smusdx r9, r2, r3            /* r9  = -B1 = W7*row[3] - W3*row[1] */
        smusdx r10,r3, r1            /* r10 =  B2 = W5*row[1] - W1*row[3] */
        .endm

/*
  Compute final part of IDCT single row without shift.
  Input in registers r4--r11
  Output in registers ip, r4--r6, lr, r8--r10
*/
        .macro idct_finish
        add    ip, r4, r8            /* r1 = A0 + B0 */
        sub    lr, r4, r8            /* r2 = A0 - B0 */
        sub    r4, r5, r9            /* r2 = A1 + B1 */
        add    r8, r5, r9            /* r2 = A1 - B1 */
        add    r5, r6, r10           /* r1 = A2 + B2 */
        sub    r9, r6, r10           /* r1 = A2 - B2 */
        add    r6, r7, r11           /* r2 = A3 + B3 */
        sub    r10,r7, r11           /* r2 = A3 - B3 */
        .endm

/*
  Compute final part of IDCT single row.
  shift = right-shift amount
  Input/output in registers r4--r11
*/
        .macro idct_finish_shift shift
        add    r3, r4, r8            /* r3 = A0 + B0 */
        sub    r2, r4, r8            /* r2 = A0 - B0 */
        mov    r4, r3, asr #\shift
        mov    r8, r2, asr #\shift

        sub    r3, r5, r9            /* r3 = A1 + B1 */
        add    r2, r5, r9            /* r2 = A1 - B1 */
        mov    r5, r3, asr #\shift
        mov    r9, r2, asr #\shift

        add    r3, r6, r10           /* r3 = A2 + B2 */
        sub    r2, r6, r10           /* r2 = A2 - B2 */
        mov    r6, r3, asr #\shift
        mov    r10,r2, asr #\shift

        add    r3, r7, r11           /* r3 = A3 + B3 */
        sub    r2, r7, r11           /* r2 = A3 - B3 */
        mov    r7, r3, asr #\shift
        mov    r11,r2, asr #\shift
        .endm

/*
  Compute final part of IDCT single row, saturating results at 8 bits.
  shift = right-shift amount
  Input/output in registers r4--r11
*/
        .macro idct_finish_shift_sat shift
        add    r3, r4, r8            /* r3 = A0 + B0 */
        sub    ip, r4, r8            /* ip = A0 - B0 */
        usat   r4, #8, r3, asr #\shift
        usat   r8, #8, ip, asr #\shift

        sub    r3, r5, r9            /* r3 = A1 + B1 */
        add    ip, r5, r9            /* ip = A1 - B1 */
        usat   r5, #8, r3, asr #\shift
        usat   r9, #8, ip, asr #\shift

        add    r3, r6, r10           /* r3 = A2 + B2 */
        sub    ip, r6, r10           /* ip = A2 - B2 */
        usat   r6, #8, r3, asr #\shift
        usat   r10,#8, ip, asr #\shift

        add    r3, r7, r11           /* r3 = A3 + B3 */
        sub    ip, r7, r11           /* ip = A3 - B3 */
        usat   r7, #8, r3, asr #\shift
        usat   r11,#8, ip, asr #\shift
        .endm

/*
  Compute IDCT of single row, storing as column.
  r0 = source
  r1 = dest
*/
function idct_row_armv6
        push   {lr}

        ldr    lr, [r0, #12]         /* lr = row[7,5] */
        ldr    ip, [r0, #4]          /* ip = row[6,4] */
        ldr    r3, [r0, #8]          /* r3 = row[3,1] */
        ldr    r2, [r0]              /* r2 = row[2,0] */
        orrs   lr, lr, ip
        itt    eq
        cmpeq  lr, r3
        cmpeq  lr, r2, lsr #16
        beq    1f
        push   {r1}
        ldr    ip, =W42              /* ip = W4 | (W2 << 16) */
        cmp    lr, #0
        beq    2f

        idct_row   ROW_SHIFT
        b      3f

2:      idct_row4  ROW_SHIFT

3:      pop    {r1}
        idct_finish_shift ROW_SHIFT

        strh   r4, [r1]
        strh   r5, [r1, #(16*2)]
        strh   r6, [r1, #(16*4)]
        strh   r7, [r1, #(16*6)]
        strh   r11,[r1, #(16*1)]
        strh   r10,[r1, #(16*3)]
        strh   r9, [r1, #(16*5)]
        strh   r8, [r1, #(16*7)]

        pop    {pc}

1:      mov    r2, r2, lsl #3
        strh   r2, [r1]
        strh   r2, [r1, #(16*2)]
        strh   r2, [r1, #(16*4)]
        strh   r2, [r1, #(16*6)]
        strh   r2, [r1, #(16*1)]
        strh   r2, [r1, #(16*3)]
        strh   r2, [r1, #(16*5)]
        strh   r2, [r1, #(16*7)]
        pop    {pc}
endfunc

/*
  Compute IDCT of single column, read as row.
  r0 = source
  r1 = dest
*/
function idct_col_armv6
        push   {r1, lr}

        ldr    r2, [r0]              /* r2 = row[2,0] */
        ldr    ip, =W42              /* ip = W4 | (W2 << 16) */
        ldr    r3, [r0, #8]          /* r3 = row[3,1] */
        idct_row COL_SHIFT
        pop    {r1}
        idct_finish_shift COL_SHIFT

        strh   r4, [r1]
        strh   r5, [r1, #(16*1)]
        strh   r6, [r1, #(16*2)]
        strh   r7, [r1, #(16*3)]
        strh   r11,[r1, #(16*4)]
        strh   r10,[r1, #(16*5)]
        strh   r9, [r1, #(16*6)]
        strh   r8, [r1, #(16*7)]

        pop    {pc}
endfunc

/*
  Compute IDCT of single column, read as row, store saturated 8-bit.
  r0 = source
  r1 = dest
  r2 = line size
*/
function idct_col_put_armv6
        push   {r1, r2, lr}

        ldr    r2, [r0]              /* r2 = row[2,0] */
        ldr    ip, =W42              /* ip = W4 | (W2 << 16) */
        ldr    r3, [r0, #8]          /* r3 = row[3,1] */
        idct_row COL_SHIFT
        pop    {r1, r2}
        idct_finish_shift_sat COL_SHIFT

        strb_post r4, r1, r2
        strb_post r5, r1, r2
        strb_post r6, r1, r2
        strb_post r7, r1, r2
        strb_post r11,r1, r2
        strb_post r10,r1, r2
        strb_post r9, r1, r2
        strb_post r8, r1, r2

        sub    r1, r1, r2, lsl #3

        pop    {pc}
endfunc

/*
  Compute IDCT of single column, read as row, add/store saturated 8-bit.
  r0 = source
  r1 = dest
  r2 = line size
*/
function idct_col_add_armv6
        push   {r1, r2, lr}

        ldr    r2, [r0]              /* r2 = row[2,0] */
        ldr    ip, =W42              /* ip = W4 | (W2 << 16) */
        ldr    r3, [r0, #8]          /* r3 = row[3,1] */
        idct_row COL_SHIFT
        pop    {r1, r2}
        idct_finish

        ldrb   r3, [r1]
        ldrb   r7, [r1, r2]
        ldrb   r11,[r1, r2, lsl #2]
        add    ip, r3, ip, asr #COL_SHIFT
        usat   ip, #8, ip
        add    r4, r7, r4, asr #COL_SHIFT
        strb_post ip, r1, r2
        ldrb   ip, [r1, r2]
        usat   r4, #8, r4
        ldrb   r11,[r1, r2, lsl #2]
        add    r5, ip, r5, asr #COL_SHIFT
        usat   r5, #8, r5
        strb_post r4, r1, r2
        ldrb   r3, [r1, r2]
        ldrb   ip, [r1, r2, lsl #2]
        strb_post r5, r1, r2
        ldrb   r7, [r1, r2]
        ldrb   r4, [r1, r2, lsl #2]
        add    r6, r3, r6, asr #COL_SHIFT
        usat   r6, #8, r6
        add    r10,r7, r10,asr #COL_SHIFT
        usat   r10,#8, r10
        add    r9, r11,r9, asr #COL_SHIFT
        usat   r9, #8, r9
        add    r8, ip, r8, asr #COL_SHIFT
        usat   r8, #8, r8
        add    lr, r4, lr, asr #COL_SHIFT
        usat   lr, #8, lr
        strb_post r6, r1, r2
        strb_post r10,r1, r2
        strb_post r9, r1, r2
        strb_post r8, r1, r2
        strb_post lr, r1, r2

        sub    r1, r1, r2, lsl #3

        pop    {pc}
endfunc

/*
  Compute 8 IDCT row transforms.
  func = IDCT row->col function
  width = width of columns in bytes
*/
        .macro idct_rows func width
        bl     \func
        add    r0, r0, #(16*2)
        add    r1, r1, #\width
        bl     \func
        add    r0, r0, #(16*2)
        add    r1, r1, #\width
        bl     \func
        add    r0, r0, #(16*2)
        add    r1, r1, #\width
        bl     \func
        sub    r0, r0, #(16*5)
        add    r1, r1, #\width
        bl     \func
        add    r0, r0, #(16*2)
        add    r1, r1, #\width
        bl     \func
        add    r0, r0, #(16*2)
        add    r1, r1, #\width
        bl     \func
        add    r0, r0, #(16*2)
        add    r1, r1, #\width
        bl     \func

        sub    r0, r0, #(16*7)
        .endm

/* void ff_simple_idct_armv6(int16_t *data); */
function ff_simple_idct_armv6, export=1
        push   {r4-r11, lr}
        sub    sp, sp, #128

        mov    r1, sp
        idct_rows idct_row_armv6, 2
        mov    r1, r0
        mov    r0, sp
        idct_rows idct_col_armv6, 2

        add    sp, sp, #128
        pop    {r4-r11, pc}
endfunc

/* ff_simple_idct_add_armv6(uint8_t *dest, ptrdiff_t line_size, int16_t *data); */
function ff_simple_idct_add_armv6, export=1
        push   {r0, r1, r4-r11, lr}
        sub    sp, sp, #128

        mov    r0, r2
        mov    r1, sp
        idct_rows idct_row_armv6, 2
        mov    r0, sp
        ldr    r1, [sp, #128]
        ldr    r2, [sp, #(128+4)]
        idct_rows idct_col_add_armv6, 1

        add    sp, sp, #(128+8)
        pop    {r4-r11, pc}
endfunc

/* ff_simple_idct_put_armv6(uint8_t *dest, ptrdiff_t line_size, int16_t *data); */
function ff_simple_idct_put_armv6, export=1
        push   {r0, r1, r4-r11, lr}
        sub    sp, sp, #128

        mov    r0, r2
        mov    r1, sp
        idct_rows idct_row_armv6, 2
        mov    r0, sp
        ldr    r1, [sp, #128]
        ldr    r2, [sp, #(128+4)]
        idct_rows idct_col_put_armv6, 1

        add    sp, sp, #(128+8)
        pop    {r4-r11, pc}
endfunc