1;
2; jquanti.asm - sample data conversion and quantization (SSE2)
3;
4; Copyright 2009 Pierre Ossman <ossman@cendio.se> for Cendio AB
5;
6; Based on
7; 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 "jsimdext.inc"
20%include "jdct.inc"
21
22; --------------------------------------------------------------------------
23        SECTION SEG_TEXT
24        BITS    32
25;
26; Load data into workspace, applying unsigned->signed conversion
27;
28; GLOBAL(void)
29; jsimd_convsamp_sse2 (JSAMPARRAY sample_data, JDIMENSION start_col,
30;                      DCTELEM * workspace);
31;
32
33%define sample_data     ebp+8           ; JSAMPARRAY sample_data
34%define start_col       ebp+12          ; JDIMENSION start_col
35%define workspace       ebp+16          ; DCTELEM * workspace
36
37        align   16
38        global  EXTN(jsimd_convsamp_sse2)
39
40EXTN(jsimd_convsamp_sse2):
41        push    ebp
42        mov     ebp,esp
43        push    ebx
44;       push    ecx             ; need not be preserved
45;       push    edx             ; need not be preserved
46        push    esi
47        push    edi
48
49        pxor    xmm6,xmm6               ; xmm6=(all 0's)
50        pcmpeqw xmm7,xmm7
51        psllw   xmm7,7                  ; xmm7={0xFF80 0xFF80 0xFF80 0xFF80 ..}
52
53        mov     esi, JSAMPARRAY [sample_data]   ; (JSAMPROW *)
54        mov     eax, JDIMENSION [start_col]
55        mov     edi, POINTER [workspace]        ; (DCTELEM *)
56        mov     ecx, DCTSIZE/4
57        alignx  16,7
58.convloop:
59        mov     ebx, JSAMPROW [esi+0*SIZEOF_JSAMPROW]   ; (JSAMPLE *)
60        mov     edx, JSAMPROW [esi+1*SIZEOF_JSAMPROW]   ; (JSAMPLE *)
61
62        movq    xmm0, XMM_MMWORD [ebx+eax*SIZEOF_JSAMPLE]       ; xmm0=(01234567)
63        movq    xmm1, XMM_MMWORD [edx+eax*SIZEOF_JSAMPLE]       ; xmm1=(89ABCDEF)
64
65        mov     ebx, JSAMPROW [esi+2*SIZEOF_JSAMPROW]   ; (JSAMPLE *)
66        mov     edx, JSAMPROW [esi+3*SIZEOF_JSAMPROW]   ; (JSAMPLE *)
67
68        movq    xmm2, XMM_MMWORD [ebx+eax*SIZEOF_JSAMPLE]       ; xmm2=(GHIJKLMN)
69        movq    xmm3, XMM_MMWORD [edx+eax*SIZEOF_JSAMPLE]       ; xmm3=(OPQRSTUV)
70
71        punpcklbw xmm0,xmm6             ; xmm0=(01234567)
72        punpcklbw xmm1,xmm6             ; xmm1=(89ABCDEF)
73        paddw     xmm0,xmm7
74        paddw     xmm1,xmm7
75        punpcklbw xmm2,xmm6             ; xmm2=(GHIJKLMN)
76        punpcklbw xmm3,xmm6             ; xmm3=(OPQRSTUV)
77        paddw     xmm2,xmm7
78        paddw     xmm3,xmm7
79
80        movdqa  XMMWORD [XMMBLOCK(0,0,edi,SIZEOF_DCTELEM)], xmm0
81        movdqa  XMMWORD [XMMBLOCK(1,0,edi,SIZEOF_DCTELEM)], xmm1
82        movdqa  XMMWORD [XMMBLOCK(2,0,edi,SIZEOF_DCTELEM)], xmm2
83        movdqa  XMMWORD [XMMBLOCK(3,0,edi,SIZEOF_DCTELEM)], xmm3
84
85        add     esi, byte 4*SIZEOF_JSAMPROW
86        add     edi, byte 4*DCTSIZE*SIZEOF_DCTELEM
87        dec     ecx
88        jnz     short .convloop
89
90        pop     edi
91        pop     esi
92;       pop     edx             ; need not be preserved
93;       pop     ecx             ; need not be preserved
94        pop     ebx
95        pop     ebp
96        ret
97
98; --------------------------------------------------------------------------
99;
100; Quantize/descale the coefficients, and store into coef_block
101;
102; This implementation is based on an algorithm described in
103;   "How to optimize for the Pentium family of microprocessors"
104;   (http://www.agner.org/assem/).
105;
106; GLOBAL(void)
107; jsimd_quantize_sse2 (JCOEFPTR coef_block, DCTELEM * divisors,
108;                      DCTELEM * workspace);
109;
110
111%define RECIPROCAL(m,n,b) XMMBLOCK(DCTSIZE*0+(m),(n),(b),SIZEOF_DCTELEM)
112%define CORRECTION(m,n,b) XMMBLOCK(DCTSIZE*1+(m),(n),(b),SIZEOF_DCTELEM)
113%define SCALE(m,n,b)      XMMBLOCK(DCTSIZE*2+(m),(n),(b),SIZEOF_DCTELEM)
114
115%define coef_block      ebp+8           ; JCOEFPTR coef_block
116%define divisors        ebp+12          ; DCTELEM * divisors
117%define workspace       ebp+16          ; DCTELEM * workspace
118
119        align   16
120        global  EXTN(jsimd_quantize_sse2)
121
122EXTN(jsimd_quantize_sse2):
123        push    ebp
124        mov     ebp,esp
125;       push    ebx             ; unused
126;       push    ecx             ; unused
127;       push    edx             ; need not be preserved
128        push    esi
129        push    edi
130
131        mov     esi, POINTER [workspace]
132        mov     edx, POINTER [divisors]
133        mov     edi, JCOEFPTR [coef_block]
134        mov     eax, DCTSIZE2/32
135        alignx  16,7
136.quantloop:
137        movdqa  xmm4, XMMWORD [XMMBLOCK(0,0,esi,SIZEOF_DCTELEM)]
138        movdqa  xmm5, XMMWORD [XMMBLOCK(1,0,esi,SIZEOF_DCTELEM)]
139        movdqa  xmm6, XMMWORD [XMMBLOCK(2,0,esi,SIZEOF_DCTELEM)]
140        movdqa  xmm7, XMMWORD [XMMBLOCK(3,0,esi,SIZEOF_DCTELEM)]
141        movdqa  xmm0,xmm4
142        movdqa  xmm1,xmm5
143        movdqa  xmm2,xmm6
144        movdqa  xmm3,xmm7
145        psraw   xmm4,(WORD_BIT-1)
146        psraw   xmm5,(WORD_BIT-1)
147        psraw   xmm6,(WORD_BIT-1)
148        psraw   xmm7,(WORD_BIT-1)
149        pxor    xmm0,xmm4
150        pxor    xmm1,xmm5
151        pxor    xmm2,xmm6
152        pxor    xmm3,xmm7
153        psubw   xmm0,xmm4               ; if (xmm0 < 0) xmm0 = -xmm0;
154        psubw   xmm1,xmm5               ; if (xmm1 < 0) xmm1 = -xmm1;
155        psubw   xmm2,xmm6               ; if (xmm2 < 0) xmm2 = -xmm2;
156        psubw   xmm3,xmm7               ; if (xmm3 < 0) xmm3 = -xmm3;
157
158        paddw   xmm0, XMMWORD [CORRECTION(0,0,edx)]  ; correction + roundfactor
159        paddw   xmm1, XMMWORD [CORRECTION(1,0,edx)]
160        paddw   xmm2, XMMWORD [CORRECTION(2,0,edx)]
161        paddw   xmm3, XMMWORD [CORRECTION(3,0,edx)]
162        pmulhuw xmm0, XMMWORD [RECIPROCAL(0,0,edx)]  ; reciprocal
163        pmulhuw xmm1, XMMWORD [RECIPROCAL(1,0,edx)]
164        pmulhuw xmm2, XMMWORD [RECIPROCAL(2,0,edx)]
165        pmulhuw xmm3, XMMWORD [RECIPROCAL(3,0,edx)]
166        pmulhuw xmm0, XMMWORD [SCALE(0,0,edx)]  ; scale
167        pmulhuw xmm1, XMMWORD [SCALE(1,0,edx)]
168        pmulhuw xmm2, XMMWORD [SCALE(2,0,edx)]
169        pmulhuw xmm3, XMMWORD [SCALE(3,0,edx)]
170
171        pxor    xmm0,xmm4
172        pxor    xmm1,xmm5
173        pxor    xmm2,xmm6
174        pxor    xmm3,xmm7
175        psubw   xmm0,xmm4
176        psubw   xmm1,xmm5
177        psubw   xmm2,xmm6
178        psubw   xmm3,xmm7
179        movdqa  XMMWORD [XMMBLOCK(0,0,edi,SIZEOF_DCTELEM)], xmm0
180        movdqa  XMMWORD [XMMBLOCK(1,0,edi,SIZEOF_DCTELEM)], xmm1
181        movdqa  XMMWORD [XMMBLOCK(2,0,edi,SIZEOF_DCTELEM)], xmm2
182        movdqa  XMMWORD [XMMBLOCK(3,0,edi,SIZEOF_DCTELEM)], xmm3
183
184        add     esi, byte 32*SIZEOF_DCTELEM
185        add     edx, byte 32*SIZEOF_DCTELEM
186        add     edi, byte 32*SIZEOF_JCOEF
187        dec     eax
188        jnz     near .quantloop
189
190        pop     edi
191        pop     esi
192;       pop     edx             ; need not be preserved
193;       pop     ecx             ; unused
194;       pop     ebx             ; unused
195        pop     ebp
196        ret
197
198; For some reason, the OS X linker does not honor the request to align the
199; segment unless we do this.
200        align   16
201