1; 2; jchuff-sse2.asm - Huffman entropy encoding (SSE2) 3; 4; Copyright (C) 2009-2011, 2014-2016, D. R. Commander. 5; Copyright (C) 2015, Matthieu Darbois. 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 an SSE2 implementation for Huffman coding of one block. 18; The following code is based directly on jchuff.c; see jchuff.c for more 19; details. 20; 21; [TAB8] 22 23%include "jsimdext.inc" 24 25; -------------------------------------------------------------------------- 26 SECTION SEG_CONST 27 28 alignz 16 29 global EXTN(jconst_huff_encode_one_block) 30 31EXTN(jconst_huff_encode_one_block): 32 33%include "jpeg_nbits_table.inc" 34 35 alignz 16 36 37; -------------------------------------------------------------------------- 38 SECTION SEG_TEXT 39 BITS 32 40 41; These macros perform the same task as the emit_bits() function in the 42; original libjpeg code. In addition to reducing overhead by explicitly 43; inlining the code, additional performance is achieved by taking into 44; account the size of the bit buffer and waiting until it is almost full 45; before emptying it. This mostly benefits 64-bit platforms, since 6 46; bytes can be stored in a 64-bit bit buffer before it has to be emptied. 47 48%macro EMIT_BYTE 0 49 sub put_bits, 8 ; put_bits -= 8; 50 mov edx, put_buffer 51 mov ecx, put_bits 52 shr edx, cl ; c = (JOCTET)GETJOCTET(put_buffer >> put_bits); 53 mov byte [eax], dl ; *buffer++ = c; 54 add eax, 1 55 cmp dl, 0xFF ; need to stuff a zero byte? 56 jne %%.EMIT_BYTE_END 57 mov byte [eax], 0 ; *buffer++ = 0; 58 add eax, 1 59%%.EMIT_BYTE_END: 60%endmacro 61 62%macro PUT_BITS 1 63 add put_bits, ecx ; put_bits += size; 64 shl put_buffer, cl ; put_buffer = (put_buffer << size); 65 or put_buffer, %1 66%endmacro 67 68%macro CHECKBUF15 0 69 cmp put_bits, 16 ; if (put_bits > 31) { 70 jl %%.CHECKBUF15_END 71 mov eax, POINTER [esp+buffer] 72 EMIT_BYTE 73 EMIT_BYTE 74 mov POINTER [esp+buffer], eax 75%%.CHECKBUF15_END: 76%endmacro 77 78%macro EMIT_BITS 1 79 PUT_BITS %1 80 CHECKBUF15 81%endmacro 82 83%macro kloop_prepare 37 ;(ko, jno0, ..., jno31, xmm0, xmm1, xmm2, xmm3) 84 pxor xmm4, xmm4 ; __m128i neg = _mm_setzero_si128(); 85 pxor xmm5, xmm5 ; __m128i neg = _mm_setzero_si128(); 86 pxor xmm6, xmm6 ; __m128i neg = _mm_setzero_si128(); 87 pxor xmm7, xmm7 ; __m128i neg = _mm_setzero_si128(); 88 pinsrw %34, word [esi + %2 * SIZEOF_WORD], 0 ; xmm_shadow[0] = block[jno0]; 89 pinsrw %35, word [esi + %10 * SIZEOF_WORD], 0 ; xmm_shadow[8] = block[jno8]; 90 pinsrw %36, word [esi + %18 * SIZEOF_WORD], 0 ; xmm_shadow[16] = block[jno16]; 91 pinsrw %37, word [esi + %26 * SIZEOF_WORD], 0 ; xmm_shadow[24] = block[jno24]; 92 pinsrw %34, word [esi + %3 * SIZEOF_WORD], 1 ; xmm_shadow[1] = block[jno1]; 93 pinsrw %35, word [esi + %11 * SIZEOF_WORD], 1 ; xmm_shadow[9] = block[jno9]; 94 pinsrw %36, word [esi + %19 * SIZEOF_WORD], 1 ; xmm_shadow[17] = block[jno17]; 95 pinsrw %37, word [esi + %27 * SIZEOF_WORD], 1 ; xmm_shadow[25] = block[jno25]; 96 pinsrw %34, word [esi + %4 * SIZEOF_WORD], 2 ; xmm_shadow[2] = block[jno2]; 97 pinsrw %35, word [esi + %12 * SIZEOF_WORD], 2 ; xmm_shadow[10] = block[jno10]; 98 pinsrw %36, word [esi + %20 * SIZEOF_WORD], 2 ; xmm_shadow[18] = block[jno18]; 99 pinsrw %37, word [esi + %28 * SIZEOF_WORD], 2 ; xmm_shadow[26] = block[jno26]; 100 pinsrw %34, word [esi + %5 * SIZEOF_WORD], 3 ; xmm_shadow[3] = block[jno3]; 101 pinsrw %35, word [esi + %13 * SIZEOF_WORD], 3 ; xmm_shadow[11] = block[jno11]; 102 pinsrw %36, word [esi + %21 * SIZEOF_WORD], 3 ; xmm_shadow[19] = block[jno19]; 103 pinsrw %37, word [esi + %29 * SIZEOF_WORD], 3 ; xmm_shadow[27] = block[jno27]; 104 pinsrw %34, word [esi + %6 * SIZEOF_WORD], 4 ; xmm_shadow[4] = block[jno4]; 105 pinsrw %35, word [esi + %14 * SIZEOF_WORD], 4 ; xmm_shadow[12] = block[jno12]; 106 pinsrw %36, word [esi + %22 * SIZEOF_WORD], 4 ; xmm_shadow[20] = block[jno20]; 107 pinsrw %37, word [esi + %30 * SIZEOF_WORD], 4 ; xmm_shadow[28] = block[jno28]; 108 pinsrw %34, word [esi + %7 * SIZEOF_WORD], 5 ; xmm_shadow[5] = block[jno5]; 109 pinsrw %35, word [esi + %15 * SIZEOF_WORD], 5 ; xmm_shadow[13] = block[jno13]; 110 pinsrw %36, word [esi + %23 * SIZEOF_WORD], 5 ; xmm_shadow[21] = block[jno21]; 111 pinsrw %37, word [esi + %31 * SIZEOF_WORD], 5 ; xmm_shadow[29] = block[jno29]; 112 pinsrw %34, word [esi + %8 * SIZEOF_WORD], 6 ; xmm_shadow[6] = block[jno6]; 113 pinsrw %35, word [esi + %16 * SIZEOF_WORD], 6 ; xmm_shadow[14] = block[jno14]; 114 pinsrw %36, word [esi + %24 * SIZEOF_WORD], 6 ; xmm_shadow[22] = block[jno22]; 115 pinsrw %37, word [esi + %32 * SIZEOF_WORD], 6 ; xmm_shadow[30] = block[jno30]; 116 pinsrw %34, word [esi + %9 * SIZEOF_WORD], 7 ; xmm_shadow[7] = block[jno7]; 117 pinsrw %35, word [esi + %17 * SIZEOF_WORD], 7 ; xmm_shadow[15] = block[jno15]; 118 pinsrw %36, word [esi + %25 * SIZEOF_WORD], 7 ; xmm_shadow[23] = block[jno23]; 119%if %1 != 32 120 pinsrw %37, word [esi + %33 * SIZEOF_WORD], 7 ; xmm_shadow[31] = block[jno31]; 121%else 122 pinsrw %37, ecx, 7 ; xmm_shadow[31] = block[jno31]; 123%endif 124 pcmpgtw xmm4, %34 ; neg = _mm_cmpgt_epi16(neg, x1); 125 pcmpgtw xmm5, %35 ; neg = _mm_cmpgt_epi16(neg, x1); 126 pcmpgtw xmm6, %36 ; neg = _mm_cmpgt_epi16(neg, x1); 127 pcmpgtw xmm7, %37 ; neg = _mm_cmpgt_epi16(neg, x1); 128 paddw %34, xmm4 ; x1 = _mm_add_epi16(x1, neg); 129 paddw %35, xmm5 ; x1 = _mm_add_epi16(x1, neg); 130 paddw %36, xmm6 ; x1 = _mm_add_epi16(x1, neg); 131 paddw %37, xmm7 ; x1 = _mm_add_epi16(x1, neg); 132 pxor %34, xmm4 ; x1 = _mm_xor_si128(x1, neg); 133 pxor %35, xmm5 ; x1 = _mm_xor_si128(x1, neg); 134 pxor %36, xmm6 ; x1 = _mm_xor_si128(x1, neg); 135 pxor %37, xmm7 ; x1 = _mm_xor_si128(x1, neg); 136 pxor xmm4, %34 ; neg = _mm_xor_si128(neg, x1); 137 pxor xmm5, %35 ; neg = _mm_xor_si128(neg, x1); 138 pxor xmm6, %36 ; neg = _mm_xor_si128(neg, x1); 139 pxor xmm7, %37 ; neg = _mm_xor_si128(neg, x1); 140 movdqa XMMWORD [esp + t1 + %1 * SIZEOF_WORD], %34 ; _mm_storeu_si128((__m128i *)(t1 + ko), x1); 141 movdqa XMMWORD [esp + t1 + (%1 + 8) * SIZEOF_WORD], %35 ; _mm_storeu_si128((__m128i *)(t1 + ko + 8), x1); 142 movdqa XMMWORD [esp + t1 + (%1 + 16) * SIZEOF_WORD], %36 ; _mm_storeu_si128((__m128i *)(t1 + ko + 16), x1); 143 movdqa XMMWORD [esp + t1 + (%1 + 24) * SIZEOF_WORD], %37 ; _mm_storeu_si128((__m128i *)(t1 + ko + 24), x1); 144 movdqa XMMWORD [esp + t2 + %1 * SIZEOF_WORD], xmm4 ; _mm_storeu_si128((__m128i *)(t2 + ko), neg); 145 movdqa XMMWORD [esp + t2 + (%1 + 8) * SIZEOF_WORD], xmm5 ; _mm_storeu_si128((__m128i *)(t2 + ko + 8), neg); 146 movdqa XMMWORD [esp + t2 + (%1 + 16) * SIZEOF_WORD], xmm6 ; _mm_storeu_si128((__m128i *)(t2 + ko + 16), neg); 147 movdqa XMMWORD [esp + t2 + (%1 + 24) * SIZEOF_WORD], xmm7 ; _mm_storeu_si128((__m128i *)(t2 + ko + 24), neg); 148%endmacro 149 150; 151; Encode a single block's worth of coefficients. 152; 153; GLOBAL(JOCTET*) 154; jsimd_huff_encode_one_block_sse2 (working_state *state, JOCTET *buffer, 155; JCOEFPTR block, int last_dc_val, 156; c_derived_tbl *dctbl, c_derived_tbl *actbl) 157; 158 159; eax + 8 = working_state *state 160; eax + 12 = JOCTET *buffer 161; eax + 16 = JCOEFPTR block 162; eax + 20 = int last_dc_val 163; eax + 24 = c_derived_tbl *dctbl 164; eax + 28 = c_derived_tbl *actbl 165 166%define pad 6*SIZEOF_DWORD ; Align to 16 bytes 167%define t1 pad 168%define t2 t1+(DCTSIZE2*SIZEOF_WORD) 169%define block t2+(DCTSIZE2*SIZEOF_WORD) 170%define actbl block+SIZEOF_DWORD 171%define buffer actbl+SIZEOF_DWORD 172%define temp buffer+SIZEOF_DWORD 173%define temp2 temp+SIZEOF_DWORD 174%define temp3 temp2+SIZEOF_DWORD 175%define temp4 temp3+SIZEOF_DWORD 176%define temp5 temp4+SIZEOF_DWORD 177%define gotptr temp5+SIZEOF_DWORD ; void *gotptr 178%define put_buffer ebx 179%define put_bits edi 180 181 align 16 182 global EXTN(jsimd_huff_encode_one_block_sse2) 183 184EXTN(jsimd_huff_encode_one_block_sse2): 185 push ebp 186 mov eax,esp ; eax = original ebp 187 sub esp, byte 4 188 and esp, byte (-SIZEOF_XMMWORD) ; align to 128 bits 189 mov [esp],eax 190 mov ebp,esp ; ebp = aligned ebp 191 sub esp, temp5+9*SIZEOF_DWORD-pad 192 push ebx 193 push ecx 194; push edx ; need not be preserved 195 push esi 196 push edi 197 push ebp 198 199 mov esi, POINTER [eax+8] ; (working_state *state) 200 mov put_buffer, DWORD [esi+8] ; put_buffer = state->cur.put_buffer; 201 mov put_bits, DWORD [esi+12] ; put_bits = state->cur.put_bits; 202 push esi ; esi is now scratch 203 204 get_GOT edx ; get GOT address 205 movpic POINTER [esp+gotptr], edx ; save GOT address 206 207 mov ecx, POINTER [eax+28] 208 mov edx, POINTER [eax+16] 209 mov esi, POINTER [eax+12] 210 mov POINTER [esp+actbl], ecx 211 mov POINTER [esp+block], edx 212 mov POINTER [esp+buffer], esi 213 214 ; Encode the DC coefficient difference per section F.1.2.1 215 mov esi, POINTER [esp+block] ; block 216 movsx ecx, word [esi] ; temp = temp2 = block[0] - last_dc_val; 217 sub ecx, DWORD [eax+20] 218 mov esi, ecx 219 220 ; This is a well-known technique for obtaining the absolute value 221 ; without a branch. It is derived from an assembly language technique 222 ; presented in "How to Optimize for the Pentium Processors", 223 ; Copyright (c) 1996, 1997 by Agner Fog. 224 mov edx, ecx 225 sar edx, 31 ; temp3 = temp >> (CHAR_BIT * sizeof(int) - 1); 226 xor ecx, edx ; temp ^= temp3; 227 sub ecx, edx ; temp -= temp3; 228 229 ; For a negative input, want temp2 = bitwise complement of abs(input) 230 ; This code assumes we are on a two's complement machine 231 add esi, edx ; temp2 += temp3; 232 mov DWORD [esp+temp], esi ; backup temp2 in temp 233 234 ; Find the number of bits needed for the magnitude of the coefficient 235 movpic ebp, POINTER [esp+gotptr] ; load GOT address (ebp) 236 movzx edx, byte [GOTOFF(ebp, jpeg_nbits_table + ecx)] ; nbits = JPEG_NBITS(temp); 237 mov DWORD [esp+temp2], edx ; backup nbits in temp2 238 239 ; Emit the Huffman-coded symbol for the number of bits 240 mov ebp, POINTER [eax+24] ; After this point, arguments are not accessible anymore 241 mov eax, INT [ebp + edx * 4] ; code = dctbl->ehufco[nbits]; 242 movzx ecx, byte [ebp + edx + 1024] ; size = dctbl->ehufsi[nbits]; 243 EMIT_BITS eax ; EMIT_BITS(code, size) 244 245 mov ecx, DWORD [esp+temp2] ; restore nbits 246 247 ; Mask off any extra bits in code 248 mov eax, 1 249 shl eax, cl 250 dec eax 251 and eax, DWORD [esp+temp] ; temp2 &= (((JLONG) 1)<<nbits) - 1; 252 253 ; Emit that number of bits of the value, if positive, 254 ; or the complement of its magnitude, if negative. 255 EMIT_BITS eax ; EMIT_BITS(temp2, nbits) 256 257 ; Prepare data 258 xor ecx, ecx 259 mov esi, POINTER [esp+block] 260 kloop_prepare 0, 1, 8, 16, 9, 2, 3, 10, 17, 24, 32, 25, \ 261 18, 11, 4, 5, 12, 19, 26, 33, 40, 48, 41, 34, \ 262 27, 20, 13, 6, 7, 14, 21, 28, 35, \ 263 xmm0, xmm1, xmm2, xmm3 264 kloop_prepare 32, 42, 49, 56, 57, 50, 43, 36, 29, 22, 15, 23, \ 265 30, 37, 44, 51, 58, 59, 52, 45, 38, 31, 39, 46, \ 266 53, 60, 61, 54, 47, 55, 62, 63, 63, \ 267 xmm0, xmm1, xmm2, xmm3 268 269 pxor xmm7, xmm7 270 movdqa xmm0, XMMWORD [esp + t1 + 0 * SIZEOF_WORD] ; __m128i tmp0 = _mm_loadu_si128((__m128i *)(t1 + 0)); 271 movdqa xmm1, XMMWORD [esp + t1 + 8 * SIZEOF_WORD] ; __m128i tmp1 = _mm_loadu_si128((__m128i *)(t1 + 8)); 272 movdqa xmm2, XMMWORD [esp + t1 + 16 * SIZEOF_WORD] ; __m128i tmp2 = _mm_loadu_si128((__m128i *)(t1 + 16)); 273 movdqa xmm3, XMMWORD [esp + t1 + 24 * SIZEOF_WORD] ; __m128i tmp3 = _mm_loadu_si128((__m128i *)(t1 + 24)); 274 pcmpeqw xmm0, xmm7 ; tmp0 = _mm_cmpeq_epi16(tmp0, zero); 275 pcmpeqw xmm1, xmm7 ; tmp1 = _mm_cmpeq_epi16(tmp1, zero); 276 pcmpeqw xmm2, xmm7 ; tmp2 = _mm_cmpeq_epi16(tmp2, zero); 277 pcmpeqw xmm3, xmm7 ; tmp3 = _mm_cmpeq_epi16(tmp3, zero); 278 packsswb xmm0, xmm1 ; tmp0 = _mm_packs_epi16(tmp0, tmp1); 279 packsswb xmm2, xmm3 ; tmp2 = _mm_packs_epi16(tmp2, tmp3); 280 pmovmskb edx, xmm0 ; index = ((uint64_t)_mm_movemask_epi8(tmp0)) << 0; 281 pmovmskb ecx, xmm2 ; index = ((uint64_t)_mm_movemask_epi8(tmp2)) << 16; 282 shl ecx, 16 283 or edx, ecx 284 not edx ; index = ~index; 285 286 lea esi, [esp+t1] 287 mov ebp, POINTER [esp+actbl] ; ebp = actbl 288 289.BLOOP: 290 bsf ecx, edx ; r = __builtin_ctzl(index); 291 jz .ELOOP 292 lea esi, [esi+ecx*2] ; k += r; 293 shr edx, cl ; index >>= r; 294 mov DWORD [esp+temp3], edx 295.BRLOOP: 296 cmp ecx, 16 ; while (r > 15) { 297 jl .ERLOOP 298 sub ecx, 16 ; r -= 16; 299 mov DWORD [esp+temp], ecx 300 mov eax, INT [ebp + 240 * 4] ; code_0xf0 = actbl->ehufco[0xf0]; 301 movzx ecx, byte [ebp + 1024 + 240] ; size_0xf0 = actbl->ehufsi[0xf0]; 302 EMIT_BITS eax ; EMIT_BITS(code_0xf0, size_0xf0) 303 mov ecx, DWORD [esp+temp] 304 jmp .BRLOOP 305.ERLOOP: 306 movsx eax, word [esi] ; temp = t1[k]; 307 movpic edx, POINTER [esp+gotptr] ; load GOT address (edx) 308 movzx eax, byte [GOTOFF(edx, jpeg_nbits_table + eax)] ; nbits = JPEG_NBITS(temp); 309 mov DWORD [esp+temp2], eax 310 ; Emit Huffman symbol for run length / number of bits 311 shl ecx, 4 ; temp3 = (r << 4) + nbits; 312 add ecx, eax 313 mov eax, INT [ebp + ecx * 4] ; code = actbl->ehufco[temp3]; 314 movzx ecx, byte [ebp + ecx + 1024] ; size = actbl->ehufsi[temp3]; 315 EMIT_BITS eax 316 317 movsx edx, word [esi+DCTSIZE2*2] ; temp2 = t2[k]; 318 ; Mask off any extra bits in code 319 mov ecx, DWORD [esp+temp2] 320 mov eax, 1 321 shl eax, cl 322 dec eax 323 and eax, edx ; temp2 &= (((JLONG) 1)<<nbits) - 1; 324 EMIT_BITS eax ; PUT_BITS(temp2, nbits) 325 mov edx, DWORD [esp+temp3] 326 add esi, 2 ; ++k; 327 shr edx, 1 ; index >>= 1; 328 329 jmp .BLOOP 330.ELOOP: 331 movdqa xmm0, XMMWORD [esp + t1 + 32 * SIZEOF_WORD] ; __m128i tmp0 = _mm_loadu_si128((__m128i *)(t1 + 0)); 332 movdqa xmm1, XMMWORD [esp + t1 + 40 * SIZEOF_WORD] ; __m128i tmp1 = _mm_loadu_si128((__m128i *)(t1 + 8)); 333 movdqa xmm2, XMMWORD [esp + t1 + 48 * SIZEOF_WORD] ; __m128i tmp2 = _mm_loadu_si128((__m128i *)(t1 + 16)); 334 movdqa xmm3, XMMWORD [esp + t1 + 56 * SIZEOF_WORD] ; __m128i tmp3 = _mm_loadu_si128((__m128i *)(t1 + 24)); 335 pcmpeqw xmm0, xmm7 ; tmp0 = _mm_cmpeq_epi16(tmp0, zero); 336 pcmpeqw xmm1, xmm7 ; tmp1 = _mm_cmpeq_epi16(tmp1, zero); 337 pcmpeqw xmm2, xmm7 ; tmp2 = _mm_cmpeq_epi16(tmp2, zero); 338 pcmpeqw xmm3, xmm7 ; tmp3 = _mm_cmpeq_epi16(tmp3, zero); 339 packsswb xmm0, xmm1 ; tmp0 = _mm_packs_epi16(tmp0, tmp1); 340 packsswb xmm2, xmm3 ; tmp2 = _mm_packs_epi16(tmp2, tmp3); 341 pmovmskb edx, xmm0 ; index = ((uint64_t)_mm_movemask_epi8(tmp0)) << 0; 342 pmovmskb ecx, xmm2 ; index = ((uint64_t)_mm_movemask_epi8(tmp2)) << 16; 343 shl ecx, 16 344 or edx, ecx 345 not edx ; index = ~index; 346 347 lea eax, [esp + t1 + (DCTSIZE2/2) * 2] 348 sub eax, esi 349 shr eax, 1 350 bsf ecx, edx ; r = __builtin_ctzl(index); 351 jz .ELOOP2 352 shr edx, cl ; index >>= r; 353 add ecx, eax 354 lea esi, [esi+ecx*2] ; k += r; 355 mov DWORD [esp+temp3], edx 356 jmp .BRLOOP2 357.BLOOP2: 358 bsf ecx, edx ; r = __builtin_ctzl(index); 359 jz .ELOOP2 360 lea esi, [esi+ecx*2] ; k += r; 361 shr edx, cl ; index >>= r; 362 mov DWORD [esp+temp3], edx 363.BRLOOP2: 364 cmp ecx, 16 ; while (r > 15) { 365 jl .ERLOOP2 366 sub ecx, 16 ; r -= 16; 367 mov DWORD [esp+temp], ecx 368 mov eax, INT [ebp + 240 * 4] ; code_0xf0 = actbl->ehufco[0xf0]; 369 movzx ecx, byte [ebp + 1024 + 240] ; size_0xf0 = actbl->ehufsi[0xf0]; 370 EMIT_BITS eax ; EMIT_BITS(code_0xf0, size_0xf0) 371 mov ecx, DWORD [esp+temp] 372 jmp .BRLOOP2 373.ERLOOP2: 374 movsx eax, word [esi] ; temp = t1[k]; 375 bsr eax, eax ; nbits = 32 - __builtin_clz(temp); 376 inc eax 377 mov DWORD [esp+temp2], eax 378 ; Emit Huffman symbol for run length / number of bits 379 shl ecx, 4 ; temp3 = (r << 4) + nbits; 380 add ecx, eax 381 mov eax, INT [ebp + ecx * 4] ; code = actbl->ehufco[temp3]; 382 movzx ecx, byte [ebp + ecx + 1024] ; size = actbl->ehufsi[temp3]; 383 EMIT_BITS eax 384 385 movsx edx, word [esi+DCTSIZE2*2] ; temp2 = t2[k]; 386 ; Mask off any extra bits in code 387 mov ecx, DWORD [esp+temp2] 388 mov eax, 1 389 shl eax, cl 390 dec eax 391 and eax, edx ; temp2 &= (((JLONG) 1)<<nbits) - 1; 392 EMIT_BITS eax ; PUT_BITS(temp2, nbits) 393 mov edx, DWORD [esp+temp3] 394 add esi, 2 ; ++k; 395 shr edx, 1 ; index >>= 1; 396 397 jmp .BLOOP2 398.ELOOP2: 399 ; If the last coef(s) were zero, emit an end-of-block code 400 lea edx, [esp + t1 + (DCTSIZE2-1) * 2] ; r = DCTSIZE2-1-k; 401 cmp edx, esi ; if (r > 0) { 402 je .EFN 403 mov eax, INT [ebp] ; code = actbl->ehufco[0]; 404 movzx ecx, byte [ebp + 1024] ; size = actbl->ehufsi[0]; 405 EMIT_BITS eax 406.EFN: 407 mov eax, [esp+buffer] 408 pop esi 409 ; Save put_buffer & put_bits 410 mov DWORD [esi+8], put_buffer ; state->cur.put_buffer = put_buffer; 411 mov DWORD [esi+12], put_bits ; state->cur.put_bits = put_bits; 412 413 pop ebp 414 pop edi 415 pop esi 416; pop edx ; need not be preserved 417 pop ecx 418 pop ebx 419 mov esp,ebp ; esp <- aligned ebp 420 pop esp ; esp <- original ebp 421 pop ebp 422 ret 423 424; For some reason, the OS X linker does not honor the request to align the 425; segment unless we do this. 426 align 16 427