1;
2; jidctfst.asm - fast integer IDCT (64-bit SSE2)
3;
4; Copyright 2009 Pierre Ossman <ossman@cendio.se> for Cendio AB
5; Copyright (C) 2009, 2016, 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; This file contains a fast, not so accurate integer implementation of
18; the inverse DCT (Discrete Cosine Transform). The following code is
19; based directly on the IJG's original jidctfst.c; see the jidctfst.c
20; for more details.
21;
22; [TAB8]
23
24%include "jsimdext.inc"
25%include "jdct.inc"
26
27; --------------------------------------------------------------------------
28
29%define CONST_BITS  8  ; 14 is also OK.
30%define PASS1_BITS  2
31
32%if IFAST_SCALE_BITS != PASS1_BITS
33%error "'IFAST_SCALE_BITS' must be equal to 'PASS1_BITS'."
34%endif
35
36%if CONST_BITS == 8
37F_1_082 equ 277              ; FIX(1.082392200)
38F_1_414 equ 362              ; FIX(1.414213562)
39F_1_847 equ 473              ; FIX(1.847759065)
40F_2_613 equ 669              ; FIX(2.613125930)
41F_1_613 equ (F_2_613 - 256)  ; FIX(2.613125930) - FIX(1)
42%else
43; NASM cannot do compile-time arithmetic on floating-point constants.
44%define DESCALE(x, n)  (((x) + (1 << ((n) - 1))) >> (n))
45F_1_082 equ DESCALE(1162209775, 30 - CONST_BITS)  ; FIX(1.082392200)
46F_1_414 equ DESCALE(1518500249, 30 - CONST_BITS)  ; FIX(1.414213562)
47F_1_847 equ DESCALE(1984016188, 30 - CONST_BITS)  ; FIX(1.847759065)
48F_2_613 equ DESCALE(2805822602, 30 - CONST_BITS)  ; FIX(2.613125930)
49F_1_613 equ (F_2_613 - (1 << CONST_BITS))         ; FIX(2.613125930) - FIX(1)
50%endif
51
52; --------------------------------------------------------------------------
53    SECTION     SEG_CONST
54
55; PRE_MULTIPLY_SCALE_BITS <= 2 (to avoid overflow)
56; CONST_BITS + CONST_SHIFT + PRE_MULTIPLY_SCALE_BITS == 16 (for pmulhw)
57
58%define PRE_MULTIPLY_SCALE_BITS  2
59%define CONST_SHIFT              (16 - PRE_MULTIPLY_SCALE_BITS - CONST_BITS)
60
61    alignz      32
62    GLOBAL_DATA(jconst_idct_ifast_sse2)
63
64EXTN(jconst_idct_ifast_sse2):
65
66PW_F1414       times 8  dw  F_1_414 << CONST_SHIFT
67PW_F1847       times 8  dw  F_1_847 << CONST_SHIFT
68PW_MF1613      times 8  dw -F_1_613 << CONST_SHIFT
69PW_F1082       times 8  dw  F_1_082 << CONST_SHIFT
70PB_CENTERJSAMP times 16 db  CENTERJSAMPLE
71
72    alignz      32
73
74; --------------------------------------------------------------------------
75    SECTION     SEG_TEXT
76    BITS        64
77;
78; Perform dequantization and inverse DCT on one block of coefficients.
79;
80; GLOBAL(void)
81; jsimd_idct_ifast_sse2(void *dct_table, JCOEFPTR coef_block,
82;                      JSAMPARRAY output_buf, JDIMENSION output_col)
83;
84
85; r10 = jpeg_component_info *compptr
86; r11 = JCOEFPTR coef_block
87; r12 = JSAMPARRAY output_buf
88; r13d = JDIMENSION output_col
89
90%define original_rbp  rbp + 0
91%define wk(i)         rbp - (WK_NUM - (i)) * SIZEOF_XMMWORD
92                                        ; xmmword wk[WK_NUM]
93%define WK_NUM        2
94
95    align       32
96    GLOBAL_FUNCTION(jsimd_idct_ifast_sse2)
97
98EXTN(jsimd_idct_ifast_sse2):
99    push        rbp
100    mov         rax, rsp                     ; rax = original rbp
101    sub         rsp, byte 4
102    and         rsp, byte (-SIZEOF_XMMWORD)  ; align to 128 bits
103    mov         [rsp], rax
104    mov         rbp, rsp                     ; rbp = aligned rbp
105    lea         rsp, [wk(0)]
106    collect_args 4
107
108    ; ---- Pass 1: process columns from input.
109
110    mov         rdx, r10                ; quantptr
111    mov         rsi, r11                ; inptr
112
113%ifndef NO_ZERO_COLUMN_TEST_IFAST_SSE2
114    mov         eax, DWORD [DWBLOCK(1,0,rsi,SIZEOF_JCOEF)]
115    or          eax, DWORD [DWBLOCK(2,0,rsi,SIZEOF_JCOEF)]
116    jnz         near .columnDCT
117
118    movdqa      xmm0, XMMWORD [XMMBLOCK(1,0,rsi,SIZEOF_JCOEF)]
119    movdqa      xmm1, XMMWORD [XMMBLOCK(2,0,rsi,SIZEOF_JCOEF)]
120    por         xmm0, XMMWORD [XMMBLOCK(3,0,rsi,SIZEOF_JCOEF)]
121    por         xmm1, XMMWORD [XMMBLOCK(4,0,rsi,SIZEOF_JCOEF)]
122    por         xmm0, XMMWORD [XMMBLOCK(5,0,rsi,SIZEOF_JCOEF)]
123    por         xmm1, XMMWORD [XMMBLOCK(6,0,rsi,SIZEOF_JCOEF)]
124    por         xmm0, XMMWORD [XMMBLOCK(7,0,rsi,SIZEOF_JCOEF)]
125    por         xmm1, xmm0
126    packsswb    xmm1, xmm1
127    packsswb    xmm1, xmm1
128    movd        eax, xmm1
129    test        rax, rax
130    jnz         short .columnDCT
131
132    ; -- AC terms all zero
133
134    movdqa      xmm0, XMMWORD [XMMBLOCK(0,0,rsi,SIZEOF_JCOEF)]
135    pmullw      xmm0, XMMWORD [XMMBLOCK(0,0,rdx,SIZEOF_ISLOW_MULT_TYPE)]
136
137    movdqa      xmm7, xmm0              ; xmm0=in0=(00 01 02 03 04 05 06 07)
138    punpcklwd   xmm0, xmm0              ; xmm0=(00 00 01 01 02 02 03 03)
139    punpckhwd   xmm7, xmm7              ; xmm7=(04 04 05 05 06 06 07 07)
140
141    pshufd      xmm6, xmm0, 0x00        ; xmm6=col0=(00 00 00 00 00 00 00 00)
142    pshufd      xmm2, xmm0, 0x55        ; xmm2=col1=(01 01 01 01 01 01 01 01)
143    pshufd      xmm5, xmm0, 0xAA        ; xmm5=col2=(02 02 02 02 02 02 02 02)
144    pshufd      xmm0, xmm0, 0xFF        ; xmm0=col3=(03 03 03 03 03 03 03 03)
145    pshufd      xmm1, xmm7, 0x00        ; xmm1=col4=(04 04 04 04 04 04 04 04)
146    pshufd      xmm4, xmm7, 0x55        ; xmm4=col5=(05 05 05 05 05 05 05 05)
147    pshufd      xmm3, xmm7, 0xAA        ; xmm3=col6=(06 06 06 06 06 06 06 06)
148    pshufd      xmm7, xmm7, 0xFF        ; xmm7=col7=(07 07 07 07 07 07 07 07)
149
150    movdqa      XMMWORD [wk(0)], xmm2   ; wk(0)=col1
151    movdqa      XMMWORD [wk(1)], xmm0   ; wk(1)=col3
152    jmp         near .column_end
153%endif
154.columnDCT:
155
156    ; -- Even part
157
158    movdqa      xmm0, XMMWORD [XMMBLOCK(0,0,rsi,SIZEOF_JCOEF)]
159    movdqa      xmm1, XMMWORD [XMMBLOCK(2,0,rsi,SIZEOF_JCOEF)]
160    pmullw      xmm0, XMMWORD [XMMBLOCK(0,0,rdx,SIZEOF_IFAST_MULT_TYPE)]
161    pmullw      xmm1, XMMWORD [XMMBLOCK(2,0,rdx,SIZEOF_IFAST_MULT_TYPE)]
162    movdqa      xmm2, XMMWORD [XMMBLOCK(4,0,rsi,SIZEOF_JCOEF)]
163    movdqa      xmm3, XMMWORD [XMMBLOCK(6,0,rsi,SIZEOF_JCOEF)]
164    pmullw      xmm2, XMMWORD [XMMBLOCK(4,0,rdx,SIZEOF_IFAST_MULT_TYPE)]
165    pmullw      xmm3, XMMWORD [XMMBLOCK(6,0,rdx,SIZEOF_IFAST_MULT_TYPE)]
166
167    movdqa      xmm4, xmm0
168    movdqa      xmm5, xmm1
169    psubw       xmm0, xmm2              ; xmm0=tmp11
170    psubw       xmm1, xmm3
171    paddw       xmm4, xmm2              ; xmm4=tmp10
172    paddw       xmm5, xmm3              ; xmm5=tmp13
173
174    psllw       xmm1, PRE_MULTIPLY_SCALE_BITS
175    pmulhw      xmm1, [rel PW_F1414]
176    psubw       xmm1, xmm5              ; xmm1=tmp12
177
178    movdqa      xmm6, xmm4
179    movdqa      xmm7, xmm0
180    psubw       xmm4, xmm5              ; xmm4=tmp3
181    psubw       xmm0, xmm1              ; xmm0=tmp2
182    paddw       xmm6, xmm5              ; xmm6=tmp0
183    paddw       xmm7, xmm1              ; xmm7=tmp1
184
185    movdqa      XMMWORD [wk(1)], xmm4   ; wk(1)=tmp3
186    movdqa      XMMWORD [wk(0)], xmm0   ; wk(0)=tmp2
187
188    ; -- Odd part
189
190    movdqa      xmm2, XMMWORD [XMMBLOCK(1,0,rsi,SIZEOF_JCOEF)]
191    movdqa      xmm3, XMMWORD [XMMBLOCK(3,0,rsi,SIZEOF_JCOEF)]
192    pmullw      xmm2, XMMWORD [XMMBLOCK(1,0,rdx,SIZEOF_IFAST_MULT_TYPE)]
193    pmullw      xmm3, XMMWORD [XMMBLOCK(3,0,rdx,SIZEOF_IFAST_MULT_TYPE)]
194    movdqa      xmm5, XMMWORD [XMMBLOCK(5,0,rsi,SIZEOF_JCOEF)]
195    movdqa      xmm1, XMMWORD [XMMBLOCK(7,0,rsi,SIZEOF_JCOEF)]
196    pmullw      xmm5, XMMWORD [XMMBLOCK(5,0,rdx,SIZEOF_IFAST_MULT_TYPE)]
197    pmullw      xmm1, XMMWORD [XMMBLOCK(7,0,rdx,SIZEOF_IFAST_MULT_TYPE)]
198
199    movdqa      xmm4, xmm2
200    movdqa      xmm0, xmm5
201    psubw       xmm2, xmm1              ; xmm2=z12
202    psubw       xmm5, xmm3              ; xmm5=z10
203    paddw       xmm4, xmm1              ; xmm4=z11
204    paddw       xmm0, xmm3              ; xmm0=z13
205
206    movdqa      xmm1, xmm5              ; xmm1=z10(unscaled)
207    psllw       xmm2, PRE_MULTIPLY_SCALE_BITS
208    psllw       xmm5, PRE_MULTIPLY_SCALE_BITS
209
210    movdqa      xmm3, xmm4
211    psubw       xmm4, xmm0
212    paddw       xmm3, xmm0              ; xmm3=tmp7
213
214    psllw       xmm4, PRE_MULTIPLY_SCALE_BITS
215    pmulhw      xmm4, [rel PW_F1414]    ; xmm4=tmp11
216
217    ; To avoid overflow...
218    ;
219    ; (Original)
220    ; tmp12 = -2.613125930 * z10 + z5;
221    ;
222    ; (This implementation)
223    ; tmp12 = (-1.613125930 - 1) * z10 + z5;
224    ;       = -1.613125930 * z10 - z10 + z5;
225
226    movdqa      xmm0, xmm5
227    paddw       xmm5, xmm2
228    pmulhw      xmm5, [rel PW_F1847]    ; xmm5=z5
229    pmulhw      xmm0, [rel PW_MF1613]
230    pmulhw      xmm2, [rel PW_F1082]
231    psubw       xmm0, xmm1
232    psubw       xmm2, xmm5              ; xmm2=tmp10
233    paddw       xmm0, xmm5              ; xmm0=tmp12
234
235    ; -- Final output stage
236
237    psubw       xmm0, xmm3              ; xmm0=tmp6
238    movdqa      xmm1, xmm6
239    movdqa      xmm5, xmm7
240    paddw       xmm6, xmm3              ; xmm6=data0=(00 01 02 03 04 05 06 07)
241    paddw       xmm7, xmm0              ; xmm7=data1=(10 11 12 13 14 15 16 17)
242    psubw       xmm1, xmm3              ; xmm1=data7=(70 71 72 73 74 75 76 77)
243    psubw       xmm5, xmm0              ; xmm5=data6=(60 61 62 63 64 65 66 67)
244    psubw       xmm4, xmm0              ; xmm4=tmp5
245
246    movdqa      xmm3, xmm6              ; transpose coefficients(phase 1)
247    punpcklwd   xmm6, xmm7              ; xmm6=(00 10 01 11 02 12 03 13)
248    punpckhwd   xmm3, xmm7              ; xmm3=(04 14 05 15 06 16 07 17)
249    movdqa      xmm0, xmm5              ; transpose coefficients(phase 1)
250    punpcklwd   xmm5, xmm1              ; xmm5=(60 70 61 71 62 72 63 73)
251    punpckhwd   xmm0, xmm1              ; xmm0=(64 74 65 75 66 76 67 77)
252
253    movdqa      xmm7, XMMWORD [wk(0)]   ; xmm7=tmp2
254    movdqa      xmm1, XMMWORD [wk(1)]   ; xmm1=tmp3
255
256    movdqa      XMMWORD [wk(0)], xmm5   ; wk(0)=(60 70 61 71 62 72 63 73)
257    movdqa      XMMWORD [wk(1)], xmm0   ; wk(1)=(64 74 65 75 66 76 67 77)
258
259    paddw       xmm2, xmm4              ; xmm2=tmp4
260    movdqa      xmm5, xmm7
261    movdqa      xmm0, xmm1
262    paddw       xmm7, xmm4              ; xmm7=data2=(20 21 22 23 24 25 26 27)
263    paddw       xmm1, xmm2              ; xmm1=data4=(40 41 42 43 44 45 46 47)
264    psubw       xmm5, xmm4              ; xmm5=data5=(50 51 52 53 54 55 56 57)
265    psubw       xmm0, xmm2              ; xmm0=data3=(30 31 32 33 34 35 36 37)
266
267    movdqa      xmm4, xmm7              ; transpose coefficients(phase 1)
268    punpcklwd   xmm7, xmm0              ; xmm7=(20 30 21 31 22 32 23 33)
269    punpckhwd   xmm4, xmm0              ; xmm4=(24 34 25 35 26 36 27 37)
270    movdqa      xmm2, xmm1              ; transpose coefficients(phase 1)
271    punpcklwd   xmm1, xmm5              ; xmm1=(40 50 41 51 42 52 43 53)
272    punpckhwd   xmm2, xmm5              ; xmm2=(44 54 45 55 46 56 47 57)
273
274    movdqa      xmm0, xmm3              ; transpose coefficients(phase 2)
275    punpckldq   xmm3, xmm4              ; xmm3=(04 14 24 34 05 15 25 35)
276    punpckhdq   xmm0, xmm4              ; xmm0=(06 16 26 36 07 17 27 37)
277    movdqa      xmm5, xmm6              ; transpose coefficients(phase 2)
278    punpckldq   xmm6, xmm7              ; xmm6=(00 10 20 30 01 11 21 31)
279    punpckhdq   xmm5, xmm7              ; xmm5=(02 12 22 32 03 13 23 33)
280
281    movdqa      xmm4, XMMWORD [wk(0)]   ; xmm4=(60 70 61 71 62 72 63 73)
282    movdqa      xmm7, XMMWORD [wk(1)]   ; xmm7=(64 74 65 75 66 76 67 77)
283
284    movdqa      XMMWORD [wk(0)], xmm3   ; wk(0)=(04 14 24 34 05 15 25 35)
285    movdqa      XMMWORD [wk(1)], xmm0   ; wk(1)=(06 16 26 36 07 17 27 37)
286
287    movdqa      xmm3, xmm1              ; transpose coefficients(phase 2)
288    punpckldq   xmm1, xmm4              ; xmm1=(40 50 60 70 41 51 61 71)
289    punpckhdq   xmm3, xmm4              ; xmm3=(42 52 62 72 43 53 63 73)
290    movdqa      xmm0, xmm2              ; transpose coefficients(phase 2)
291    punpckldq   xmm2, xmm7              ; xmm2=(44 54 64 74 45 55 65 75)
292    punpckhdq   xmm0, xmm7              ; xmm0=(46 56 66 76 47 57 67 77)
293
294    movdqa      xmm4, xmm6              ; transpose coefficients(phase 3)
295    punpcklqdq  xmm6, xmm1              ; xmm6=col0=(00 10 20 30 40 50 60 70)
296    punpckhqdq  xmm4, xmm1              ; xmm4=col1=(01 11 21 31 41 51 61 71)
297    movdqa      xmm7, xmm5              ; transpose coefficients(phase 3)
298    punpcklqdq  xmm5, xmm3              ; xmm5=col2=(02 12 22 32 42 52 62 72)
299    punpckhqdq  xmm7, xmm3              ; xmm7=col3=(03 13 23 33 43 53 63 73)
300
301    movdqa      xmm1, XMMWORD [wk(0)]   ; xmm1=(04 14 24 34 05 15 25 35)
302    movdqa      xmm3, XMMWORD [wk(1)]   ; xmm3=(06 16 26 36 07 17 27 37)
303
304    movdqa      XMMWORD [wk(0)], xmm4   ; wk(0)=col1
305    movdqa      XMMWORD [wk(1)], xmm7   ; wk(1)=col3
306
307    movdqa      xmm4, xmm1              ; transpose coefficients(phase 3)
308    punpcklqdq  xmm1, xmm2              ; xmm1=col4=(04 14 24 34 44 54 64 74)
309    punpckhqdq  xmm4, xmm2              ; xmm4=col5=(05 15 25 35 45 55 65 75)
310    movdqa      xmm7, xmm3              ; transpose coefficients(phase 3)
311    punpcklqdq  xmm3, xmm0              ; xmm3=col6=(06 16 26 36 46 56 66 76)
312    punpckhqdq  xmm7, xmm0              ; xmm7=col7=(07 17 27 37 47 57 67 77)
313.column_end:
314
315    ; -- Prefetch the next coefficient block
316
317    prefetchnta [rsi + DCTSIZE2*SIZEOF_JCOEF + 0*32]
318    prefetchnta [rsi + DCTSIZE2*SIZEOF_JCOEF + 1*32]
319    prefetchnta [rsi + DCTSIZE2*SIZEOF_JCOEF + 2*32]
320    prefetchnta [rsi + DCTSIZE2*SIZEOF_JCOEF + 3*32]
321
322    ; ---- Pass 2: process rows from work array, store into output array.
323
324    mov         rax, [original_rbp]
325    mov         rdi, r12                ; (JSAMPROW *)
326    mov         eax, r13d
327
328    ; -- Even part
329
330    ; xmm6=col0, xmm5=col2, xmm1=col4, xmm3=col6
331
332    movdqa      xmm2, xmm6
333    movdqa      xmm0, xmm5
334    psubw       xmm6, xmm1              ; xmm6=tmp11
335    psubw       xmm5, xmm3
336    paddw       xmm2, xmm1              ; xmm2=tmp10
337    paddw       xmm0, xmm3              ; xmm0=tmp13
338
339    psllw       xmm5, PRE_MULTIPLY_SCALE_BITS
340    pmulhw      xmm5, [rel PW_F1414]
341    psubw       xmm5, xmm0              ; xmm5=tmp12
342
343    movdqa      xmm1, xmm2
344    movdqa      xmm3, xmm6
345    psubw       xmm2, xmm0              ; xmm2=tmp3
346    psubw       xmm6, xmm5              ; xmm6=tmp2
347    paddw       xmm1, xmm0              ; xmm1=tmp0
348    paddw       xmm3, xmm5              ; xmm3=tmp1
349
350    movdqa      xmm0, XMMWORD [wk(0)]   ; xmm0=col1
351    movdqa      xmm5, XMMWORD [wk(1)]   ; xmm5=col3
352
353    movdqa      XMMWORD [wk(0)], xmm2   ; wk(0)=tmp3
354    movdqa      XMMWORD [wk(1)], xmm6   ; wk(1)=tmp2
355
356    ; -- Odd part
357
358    ; xmm0=col1, xmm5=col3, xmm4=col5, xmm7=col7
359
360    movdqa      xmm2, xmm0
361    movdqa      xmm6, xmm4
362    psubw       xmm0, xmm7              ; xmm0=z12
363    psubw       xmm4, xmm5              ; xmm4=z10
364    paddw       xmm2, xmm7              ; xmm2=z11
365    paddw       xmm6, xmm5              ; xmm6=z13
366
367    movdqa      xmm7, xmm4              ; xmm7=z10(unscaled)
368    psllw       xmm0, PRE_MULTIPLY_SCALE_BITS
369    psllw       xmm4, PRE_MULTIPLY_SCALE_BITS
370
371    movdqa      xmm5, xmm2
372    psubw       xmm2, xmm6
373    paddw       xmm5, xmm6              ; xmm5=tmp7
374
375    psllw       xmm2, PRE_MULTIPLY_SCALE_BITS
376    pmulhw      xmm2, [rel PW_F1414]    ; xmm2=tmp11
377
378    ; To avoid overflow...
379    ;
380    ; (Original)
381    ; tmp12 = -2.613125930 * z10 + z5;
382    ;
383    ; (This implementation)
384    ; tmp12 = (-1.613125930 - 1) * z10 + z5;
385    ;       = -1.613125930 * z10 - z10 + z5;
386
387    movdqa      xmm6, xmm4
388    paddw       xmm4, xmm0
389    pmulhw      xmm4, [rel PW_F1847]    ; xmm4=z5
390    pmulhw      xmm6, [rel PW_MF1613]
391    pmulhw      xmm0, [rel PW_F1082]
392    psubw       xmm6, xmm7
393    psubw       xmm0, xmm4              ; xmm0=tmp10
394    paddw       xmm6, xmm4              ; xmm6=tmp12
395
396    ; -- Final output stage
397
398    psubw       xmm6, xmm5              ; xmm6=tmp6
399    movdqa      xmm7, xmm1
400    movdqa      xmm4, xmm3
401    paddw       xmm1, xmm5              ; xmm1=data0=(00 10 20 30 40 50 60 70)
402    paddw       xmm3, xmm6              ; xmm3=data1=(01 11 21 31 41 51 61 71)
403    psraw       xmm1, (PASS1_BITS+3)    ; descale
404    psraw       xmm3, (PASS1_BITS+3)    ; descale
405    psubw       xmm7, xmm5              ; xmm7=data7=(07 17 27 37 47 57 67 77)
406    psubw       xmm4, xmm6              ; xmm4=data6=(06 16 26 36 46 56 66 76)
407    psraw       xmm7, (PASS1_BITS+3)    ; descale
408    psraw       xmm4, (PASS1_BITS+3)    ; descale
409    psubw       xmm2, xmm6              ; xmm2=tmp5
410
411    packsswb    xmm1, xmm4        ; xmm1=(00 10 20 30 40 50 60 70 06 16 26 36 46 56 66 76)
412    packsswb    xmm3, xmm7        ; xmm3=(01 11 21 31 41 51 61 71 07 17 27 37 47 57 67 77)
413
414    movdqa      xmm5, XMMWORD [wk(1)]   ; xmm5=tmp2
415    movdqa      xmm6, XMMWORD [wk(0)]   ; xmm6=tmp3
416
417    paddw       xmm0, xmm2              ; xmm0=tmp4
418    movdqa      xmm4, xmm5
419    movdqa      xmm7, xmm6
420    paddw       xmm5, xmm2              ; xmm5=data2=(02 12 22 32 42 52 62 72)
421    paddw       xmm6, xmm0              ; xmm6=data4=(04 14 24 34 44 54 64 74)
422    psraw       xmm5, (PASS1_BITS+3)    ; descale
423    psraw       xmm6, (PASS1_BITS+3)    ; descale
424    psubw       xmm4, xmm2              ; xmm4=data5=(05 15 25 35 45 55 65 75)
425    psubw       xmm7, xmm0              ; xmm7=data3=(03 13 23 33 43 53 63 73)
426    psraw       xmm4, (PASS1_BITS+3)    ; descale
427    psraw       xmm7, (PASS1_BITS+3)    ; descale
428
429    movdqa      xmm2, [rel PB_CENTERJSAMP]  ; xmm2=[rel PB_CENTERJSAMP]
430
431    packsswb    xmm5, xmm6        ; xmm5=(02 12 22 32 42 52 62 72 04 14 24 34 44 54 64 74)
432    packsswb    xmm7, xmm4        ; xmm7=(03 13 23 33 43 53 63 73 05 15 25 35 45 55 65 75)
433
434    paddb       xmm1, xmm2
435    paddb       xmm3, xmm2
436    paddb       xmm5, xmm2
437    paddb       xmm7, xmm2
438
439    movdqa      xmm0, xmm1        ; transpose coefficients(phase 1)
440    punpcklbw   xmm1, xmm3        ; xmm1=(00 01 10 11 20 21 30 31 40 41 50 51 60 61 70 71)
441    punpckhbw   xmm0, xmm3        ; xmm0=(06 07 16 17 26 27 36 37 46 47 56 57 66 67 76 77)
442    movdqa      xmm6, xmm5        ; transpose coefficients(phase 1)
443    punpcklbw   xmm5, xmm7        ; xmm5=(02 03 12 13 22 23 32 33 42 43 52 53 62 63 72 73)
444    punpckhbw   xmm6, xmm7        ; xmm6=(04 05 14 15 24 25 34 35 44 45 54 55 64 65 74 75)
445
446    movdqa      xmm4, xmm1        ; transpose coefficients(phase 2)
447    punpcklwd   xmm1, xmm5        ; xmm1=(00 01 02 03 10 11 12 13 20 21 22 23 30 31 32 33)
448    punpckhwd   xmm4, xmm5        ; xmm4=(40 41 42 43 50 51 52 53 60 61 62 63 70 71 72 73)
449    movdqa      xmm2, xmm6        ; transpose coefficients(phase 2)
450    punpcklwd   xmm6, xmm0        ; xmm6=(04 05 06 07 14 15 16 17 24 25 26 27 34 35 36 37)
451    punpckhwd   xmm2, xmm0        ; xmm2=(44 45 46 47 54 55 56 57 64 65 66 67 74 75 76 77)
452
453    movdqa      xmm3, xmm1        ; transpose coefficients(phase 3)
454    punpckldq   xmm1, xmm6        ; xmm1=(00 01 02 03 04 05 06 07 10 11 12 13 14 15 16 17)
455    punpckhdq   xmm3, xmm6        ; xmm3=(20 21 22 23 24 25 26 27 30 31 32 33 34 35 36 37)
456    movdqa      xmm7, xmm4        ; transpose coefficients(phase 3)
457    punpckldq   xmm4, xmm2        ; xmm4=(40 41 42 43 44 45 46 47 50 51 52 53 54 55 56 57)
458    punpckhdq   xmm7, xmm2        ; xmm7=(60 61 62 63 64 65 66 67 70 71 72 73 74 75 76 77)
459
460    pshufd      xmm5, xmm1, 0x4E  ; xmm5=(10 11 12 13 14 15 16 17 00 01 02 03 04 05 06 07)
461    pshufd      xmm0, xmm3, 0x4E  ; xmm0=(30 31 32 33 34 35 36 37 20 21 22 23 24 25 26 27)
462    pshufd      xmm6, xmm4, 0x4E  ; xmm6=(50 51 52 53 54 55 56 57 40 41 42 43 44 45 46 47)
463    pshufd      xmm2, xmm7, 0x4E  ; xmm2=(70 71 72 73 74 75 76 77 60 61 62 63 64 65 66 67)
464
465    mov         rdx, JSAMPROW [rdi+0*SIZEOF_JSAMPROW]
466    mov         rsi, JSAMPROW [rdi+2*SIZEOF_JSAMPROW]
467    movq        XMM_MMWORD [rdx+rax*SIZEOF_JSAMPLE], xmm1
468    movq        XMM_MMWORD [rsi+rax*SIZEOF_JSAMPLE], xmm3
469    mov         rdx, JSAMPROW [rdi+4*SIZEOF_JSAMPROW]
470    mov         rsi, JSAMPROW [rdi+6*SIZEOF_JSAMPROW]
471    movq        XMM_MMWORD [rdx+rax*SIZEOF_JSAMPLE], xmm4
472    movq        XMM_MMWORD [rsi+rax*SIZEOF_JSAMPLE], xmm7
473
474    mov         rdx, JSAMPROW [rdi+1*SIZEOF_JSAMPROW]
475    mov         rsi, JSAMPROW [rdi+3*SIZEOF_JSAMPROW]
476    movq        XMM_MMWORD [rdx+rax*SIZEOF_JSAMPLE], xmm5
477    movq        XMM_MMWORD [rsi+rax*SIZEOF_JSAMPLE], xmm0
478    mov         rdx, JSAMPROW [rdi+5*SIZEOF_JSAMPROW]
479    mov         rsi, JSAMPROW [rdi+7*SIZEOF_JSAMPROW]
480    movq        XMM_MMWORD [rdx+rax*SIZEOF_JSAMPLE], xmm6
481    movq        XMM_MMWORD [rsi+rax*SIZEOF_JSAMPLE], xmm2
482
483    uncollect_args 4
484    mov         rsp, rbp                ; rsp <- aligned rbp
485    pop         rsp                     ; rsp <- original rbp
486    pop         rbp
487    ret
488    ret
489
490; For some reason, the OS X linker does not honor the request to align the
491; segment unless we do this.
492    align       32
493