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comparison: media/libjpeg/simd/jcqntmmx.asm
media/libjpeg/simd/jcqntmmx.asm
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| -1:000000000000 | 0:3165fa83b286 |
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| 1 ; | |
| 2 ; jcqntmmx.asm - sample data conversion and quantization (MMX) | |
| 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_mmx (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_mmx) | |
| 39 | |
| 40 EXTN(jsimd_convsamp_mmx): | |
| 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 mm6,mm6 ; mm6=(all 0's) | |
| 50 pcmpeqw mm7,mm7 | |
| 51 psllw mm7,7 ; mm7={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 mm0, MMWORD [ebx+eax*SIZEOF_JSAMPLE] ; mm0=(01234567) | |
| 63 movq mm1, MMWORD [edx+eax*SIZEOF_JSAMPLE] ; mm1=(89ABCDEF) | |
| 64 | |
| 65 mov ebx, JSAMPROW [esi+2*SIZEOF_JSAMPROW] ; (JSAMPLE *) | |
| 66 mov edx, JSAMPROW [esi+3*SIZEOF_JSAMPROW] ; (JSAMPLE *) | |
| 67 | |
| 68 movq mm2, MMWORD [ebx+eax*SIZEOF_JSAMPLE] ; mm2=(GHIJKLMN) | |
| 69 movq mm3, MMWORD [edx+eax*SIZEOF_JSAMPLE] ; mm3=(OPQRSTUV) | |
| 70 | |
| 71 movq mm4,mm0 | |
| 72 punpcklbw mm0,mm6 ; mm0=(0123) | |
| 73 punpckhbw mm4,mm6 ; mm4=(4567) | |
| 74 movq mm5,mm1 | |
| 75 punpcklbw mm1,mm6 ; mm1=(89AB) | |
| 76 punpckhbw mm5,mm6 ; mm5=(CDEF) | |
| 77 | |
| 78 paddw mm0,mm7 | |
| 79 paddw mm4,mm7 | |
| 80 paddw mm1,mm7 | |
| 81 paddw mm5,mm7 | |
| 82 | |
| 83 movq MMWORD [MMBLOCK(0,0,edi,SIZEOF_DCTELEM)], mm0 | |
| 84 movq MMWORD [MMBLOCK(0,1,edi,SIZEOF_DCTELEM)], mm4 | |
| 85 movq MMWORD [MMBLOCK(1,0,edi,SIZEOF_DCTELEM)], mm1 | |
| 86 movq MMWORD [MMBLOCK(1,1,edi,SIZEOF_DCTELEM)], mm5 | |
| 87 | |
| 88 movq mm0,mm2 | |
| 89 punpcklbw mm2,mm6 ; mm2=(GHIJ) | |
| 90 punpckhbw mm0,mm6 ; mm0=(KLMN) | |
| 91 movq mm4,mm3 | |
| 92 punpcklbw mm3,mm6 ; mm3=(OPQR) | |
| 93 punpckhbw mm4,mm6 ; mm4=(STUV) | |
| 94 | |
| 95 paddw mm2,mm7 | |
| 96 paddw mm0,mm7 | |
| 97 paddw mm3,mm7 | |
| 98 paddw mm4,mm7 | |
| 99 | |
| 100 movq MMWORD [MMBLOCK(2,0,edi,SIZEOF_DCTELEM)], mm2 | |
| 101 movq MMWORD [MMBLOCK(2,1,edi,SIZEOF_DCTELEM)], mm0 | |
| 102 movq MMWORD [MMBLOCK(3,0,edi,SIZEOF_DCTELEM)], mm3 | |
| 103 movq MMWORD [MMBLOCK(3,1,edi,SIZEOF_DCTELEM)], mm4 | |
| 104 | |
| 105 add esi, byte 4*SIZEOF_JSAMPROW | |
| 106 add edi, byte 4*DCTSIZE*SIZEOF_DCTELEM | |
| 107 dec ecx | |
| 108 jnz short .convloop | |
| 109 | |
| 110 emms ; empty MMX state | |
| 111 | |
| 112 pop edi | |
| 113 pop esi | |
| 114 ; pop edx ; need not be preserved | |
| 115 ; pop ecx ; need not be preserved | |
| 116 pop ebx | |
| 117 pop ebp | |
| 118 ret | |
| 119 | |
| 120 ; -------------------------------------------------------------------------- | |
| 121 ; | |
| 122 ; Quantize/descale the coefficients, and store into coef_block | |
| 123 ; | |
| 124 ; This implementation is based on an algorithm described in | |
| 125 ; "How to optimize for the Pentium family of microprocessors" | |
| 126 ; (http://www.agner.org/assem/). | |
| 127 ; | |
| 128 ; GLOBAL(void) | |
| 129 ; jsimd_quantize_mmx (JCOEFPTR coef_block, DCTELEM * divisors, | |
| 130 ; DCTELEM * workspace); | |
| 131 ; | |
| 132 | |
| 133 %define RECIPROCAL(m,n,b) MMBLOCK(DCTSIZE*0+(m),(n),(b),SIZEOF_DCTELEM) | |
| 134 %define CORRECTION(m,n,b) MMBLOCK(DCTSIZE*1+(m),(n),(b),SIZEOF_DCTELEM) | |
| 135 %define SCALE(m,n,b) MMBLOCK(DCTSIZE*2+(m),(n),(b),SIZEOF_DCTELEM) | |
| 136 %define SHIFT(m,n,b) MMBLOCK(DCTSIZE*3+(m),(n),(b),SIZEOF_DCTELEM) | |
| 137 | |
| 138 %define coef_block ebp+8 ; JCOEFPTR coef_block | |
| 139 %define divisors ebp+12 ; DCTELEM * divisors | |
| 140 %define workspace ebp+16 ; DCTELEM * workspace | |
| 141 | |
| 142 align 16 | |
| 143 global EXTN(jsimd_quantize_mmx) | |
| 144 | |
| 145 EXTN(jsimd_quantize_mmx): | |
| 146 push ebp | |
| 147 mov ebp,esp | |
| 148 ; push ebx ; unused | |
| 149 ; push ecx ; unused | |
| 150 ; push edx ; need not be preserved | |
| 151 push esi | |
| 152 push edi | |
| 153 | |
| 154 mov esi, POINTER [workspace] | |
| 155 mov edx, POINTER [divisors] | |
| 156 mov edi, JCOEFPTR [coef_block] | |
| 157 mov ah, 2 | |
| 158 alignx 16,7 | |
| 159 .quantloop1: | |
| 160 mov al, DCTSIZE2/8/2 | |
| 161 alignx 16,7 | |
| 162 .quantloop2: | |
| 163 movq mm2, MMWORD [MMBLOCK(0,0,esi,SIZEOF_DCTELEM)] | |
| 164 movq mm3, MMWORD [MMBLOCK(0,1,esi,SIZEOF_DCTELEM)] | |
| 165 | |
| 166 movq mm0,mm2 | |
| 167 movq mm1,mm3 | |
| 168 | |
| 169 psraw mm2,(WORD_BIT-1) ; -1 if value < 0, 0 otherwise | |
| 170 psraw mm3,(WORD_BIT-1) | |
| 171 | |
| 172 pxor mm0,mm2 ; val = -val | |
| 173 pxor mm1,mm3 | |
| 174 psubw mm0,mm2 | |
| 175 psubw mm1,mm3 | |
| 176 | |
| 177 ; | |
| 178 ; MMX is an annoyingly crappy instruction set. It has two | |
| 179 ; misfeatures that are causing problems here: | |
| 180 ; | |
| 181 ; - All multiplications are signed. | |
| 182 ; | |
| 183 ; - The second operand for the shifts is not treated as packed. | |
| 184 ; | |
| 185 ; | |
| 186 ; We work around the first problem by implementing this algorithm: | |
| 187 ; | |
| 188 ; unsigned long unsigned_multiply(unsigned short x, unsigned short y) | |
| 189 ; { | |
| 190 ; enum { SHORT_BIT = 16 }; | |
| 191 ; signed short sx = (signed short) x; | |
| 192 ; signed short sy = (signed short) y; | |
| 193 ; signed long sz; | |
| 194 ; | |
| 195 ; sz = (long) sx * (long) sy; /* signed multiply */ | |
| 196 ; | |
| 197 ; if (sx < 0) sz += (long) sy << SHORT_BIT; | |
| 198 ; if (sy < 0) sz += (long) sx << SHORT_BIT; | |
| 199 ; | |
| 200 ; return (unsigned long) sz; | |
| 201 ; } | |
| 202 ; | |
| 203 ; (note that a negative sx adds _sy_ and vice versa) | |
| 204 ; | |
| 205 ; For the second problem, we replace the shift by a multiplication. | |
| 206 ; Unfortunately that means we have to deal with the signed issue again. | |
| 207 ; | |
| 208 | |
| 209 paddw mm0, MMWORD [CORRECTION(0,0,edx)] ; correction + roundfactor | |
| 210 paddw mm1, MMWORD [CORRECTION(0,1,edx)] | |
| 211 | |
| 212 movq mm4,mm0 ; store current value for later | |
| 213 movq mm5,mm1 | |
| 214 pmulhw mm0, MMWORD [RECIPROCAL(0,0,edx)] ; reciprocal | |
| 215 pmulhw mm1, MMWORD [RECIPROCAL(0,1,edx)] | |
| 216 paddw mm0,mm4 ; reciprocal is always negative (MSB=1), | |
| 217 paddw mm1,mm5 ; so we always need to add the initial value | |
| 218 ; (input value is never negative as we | |
| 219 ; inverted it at the start of this routine) | |
| 220 | |
| 221 ; here it gets a bit tricky as both scale | |
| 222 ; and mm0/mm1 can be negative | |
| 223 movq mm6, MMWORD [SCALE(0,0,edx)] ; scale | |
| 224 movq mm7, MMWORD [SCALE(0,1,edx)] | |
| 225 movq mm4,mm0 | |
| 226 movq mm5,mm1 | |
| 227 pmulhw mm0,mm6 | |
| 228 pmulhw mm1,mm7 | |
| 229 | |
| 230 psraw mm6,(WORD_BIT-1) ; determine if scale is negative | |
| 231 psraw mm7,(WORD_BIT-1) | |
| 232 | |
| 233 pand mm6,mm4 ; and add input if it is | |
| 234 pand mm7,mm5 | |
| 235 paddw mm0,mm6 | |
| 236 paddw mm1,mm7 | |
| 237 | |
| 238 psraw mm4,(WORD_BIT-1) ; then check if negative input | |
| 239 psraw mm5,(WORD_BIT-1) | |
| 240 | |
| 241 pand mm4, MMWORD [SCALE(0,0,edx)] ; and add scale if it is | |
| 242 pand mm5, MMWORD [SCALE(0,1,edx)] | |
| 243 paddw mm0,mm4 | |
| 244 paddw mm1,mm5 | |
| 245 | |
| 246 pxor mm0,mm2 ; val = -val | |
| 247 pxor mm1,mm3 | |
| 248 psubw mm0,mm2 | |
| 249 psubw mm1,mm3 | |
| 250 | |
| 251 movq MMWORD [MMBLOCK(0,0,edi,SIZEOF_DCTELEM)], mm0 | |
| 252 movq MMWORD [MMBLOCK(0,1,edi,SIZEOF_DCTELEM)], mm1 | |
| 253 | |
| 254 add esi, byte 8*SIZEOF_DCTELEM | |
| 255 add edx, byte 8*SIZEOF_DCTELEM | |
| 256 add edi, byte 8*SIZEOF_JCOEF | |
| 257 dec al | |
| 258 jnz near .quantloop2 | |
| 259 dec ah | |
| 260 jnz near .quantloop1 ; to avoid branch misprediction | |
| 261 | |
| 262 emms ; empty MMX state | |
| 263 | |
| 264 pop edi | |
| 265 pop esi | |
| 266 ; pop edx ; need not be preserved | |
| 267 ; pop ecx ; unused | |
| 268 ; pop ebx ; unused | |
| 269 pop ebp | |
| 270 ret | |
| 271 | |
| 272 ; For some reason, the OS X linker does not honor the request to align the | |
| 273 ; segment unless we do this. | |
| 274 align 16 |
