source/libs/zlib/zlib-src/contrib/masmx64/inffasx64.asm

   1 ; inffasx64.asm is a hand tuned assembler version of inffast.c - fast decoding
   2 ; version for AMD64 on Windows using Microsoft C compiler
   3 ;
   4 ; inffasx64.asm is automatically convert from AMD64 portion of inffas86.c
   5 ; inffasx64.asm is called by inffas8664.c, which contain more info.
   6
   7
   8 ; to compile this file, I use option
   9 ;   ml64.exe /Flinffasx64 /c /Zi inffasx64.asm
  10 ;   with Microsoft Macro Assembler (x64) for AMD64
  11 ;
  12
  13 ; This file compile with Microsoft Macro Assembler (x64) for AMD64
  14 ;
  15 ;   ml64.exe is given with Visual Studio 2005/2008/2010 and Windows WDK
  16 ;
  17 ;   (you can get Windows WDK with ml64 for AMD64 from
  18 ;      http://www.microsoft.com/whdc/Devtools/wdk/default.mspx for low price)
  19 ;
  20
  21
  22 .code
  23 inffas8664fnc PROC
  24
  25 ; see http://weblogs.asp.net/oldnewthing/archive/2004/01/14/58579.aspx and
  26 ; http://msdn.microsoft.com/library/en-us/kmarch/hh/kmarch/64bitAMD_8e951dd2-ee77-4728-8702-55ce4b5dd24a.xml.asp
  27 ;
  28 ; All registers must be preserved across the call, except for
  29 ;   rax, rcx, rdx, r8, r-9, r10, and r11, which are scratch.
  30
  31
  32         mov [rsp-8],rsi
  33         mov [rsp-16],rdi
  34         mov [rsp-24],r12
  35         mov [rsp-32],r13
  36         mov [rsp-40],r14
  37         mov [rsp-48],r15
  38         mov [rsp-56],rbx
  39
  40         mov rax,rcx
  41
  42         mov     [rax+8], rbp       ; /* save regs rbp and rsp */
  43         mov     [rax], rsp
  44
  45         mov     rsp, rax          ; /* make rsp point to &ar */
  46
  47         mov     rsi, [rsp+16]      ; /* rsi  = in */
  48         mov     rdi, [rsp+32]      ; /* rdi  = out */
  49         mov     r9, [rsp+24]       ; /* r9   = last */
  50         mov     r10, [rsp+48]      ; /* r10  = end */
  51         mov     rbp, [rsp+64]      ; /* rbp  = lcode */
  52         mov     r11, [rsp+72]      ; /* r11  = dcode */
  53         mov     rdx, [rsp+80]      ; /* rdx  = hold */
  54         mov     ebx, [rsp+88]      ; /* ebx  = bits */
  55         mov     r12d, [rsp+100]    ; /* r12d = lmask */
  56         mov     r13d, [rsp+104]    ; /* r13d = dmask */
  57                                           ; /* r14d = len */
  58                                           ; /* r15d = dist */
  59
  60
  61         cld
  62         cmp     r10, rdi
  63         je      L_one_time           ; /* if only one decode left */
  64         cmp     r9, rsi
  65
  66     jne L_do_loop
  67
  68
  69 L_one_time:
  70         mov     r8, r12           ; /* r8 = lmask */
  71         cmp     bl, 32
  72         ja      L_get_length_code_one_time
  73
  74         lodsd                         ; /* eax = *(uint *)in++ */
  75         mov     cl, bl            ; /* cl = bits, needs it for shifting */
  76         add     bl, 32             ; /* bits += 32 */
  77         shl     rax, cl
  78         or      rdx, rax          ; /* hold |= *((uint *)in)++ << bits */
  79         jmp     L_get_length_code_one_time
  80
  81 ALIGN 4
  82 L_while_test:
  83         cmp     r10, rdi
  84         jbe     L_break_loop
  85         cmp     r9, rsi
  86         jbe     L_break_loop
  87
  88 L_do_loop:
  89         mov     r8, r12           ; /* r8 = lmask */
  90         cmp     bl, 32
  91         ja      L_get_length_code    ; /* if (32 < bits) */
  92
  93         lodsd                         ; /* eax = *(uint *)in++ */
  94         mov     cl, bl            ; /* cl = bits, needs it for shifting */
  95         add     bl, 32             ; /* bits += 32 */
  96         shl     rax, cl
  97         or      rdx, rax          ; /* hold |= *((uint *)in)++ << bits */
  98
  99 L_get_length_code:
 100         and     r8, rdx            ; /* r8 &= hold */
 101         mov     eax, [rbp+r8*4]  ; /* eax = lcode[hold & lmask] */
 102
 103         mov     cl, ah            ; /* cl = this.bits */
 104         sub     bl, ah            ; /* bits -= this.bits */
 105         shr     rdx, cl           ; /* hold >>= this.bits */
 106
 107         test    al, al
 108         jnz     L_test_for_length_base ; /* if (op != 0) 45.7% */
 109
 110         mov     r8, r12            ; /* r8 = lmask */
 111         shr     eax, 16            ; /* output this.val char */
 112         stosb
 113
 114 L_get_length_code_one_time:
 115         and     r8, rdx            ; /* r8 &= hold */
 116         mov     eax, [rbp+r8*4] ; /* eax = lcode[hold & lmask] */
 117
 118 L_dolen:
 119         mov     cl, ah            ; /* cl = this.bits */
 120         sub     bl, ah            ; /* bits -= this.bits */
 121         shr     rdx, cl           ; /* hold >>= this.bits */
 122
 123         test    al, al
 124         jnz     L_test_for_length_base ; /* if (op != 0) 45.7% */
 125
 126         shr     eax, 16            ; /* output this.val char */
 127         stosb
 128         jmp     L_while_test
 129
 130 ALIGN 4
 131 L_test_for_length_base:
 132         mov     r14d, eax         ; /* len = this */
 133         shr     r14d, 16           ; /* len = this.val */
 134         mov     cl, al
 135
 136         test    al, 16
 137         jz      L_test_for_second_level_length ; /* if ((op & 16) == 0) 8% */
 138         and     cl, 15             ; /* op &= 15 */
 139         jz      L_decode_distance    ; /* if (!op) */
 140
 141 L_add_bits_to_len:
 142         sub     bl, cl
 143         xor     eax, eax
 144         inc     eax
 145         shl     eax, cl
 146         dec     eax
 147         and     eax, edx          ; /* eax &= hold */
 148         shr     rdx, cl
 149         add     r14d, eax         ; /* len += hold & mask[op] */
 150
 151 L_decode_distance:
 152         mov     r8, r13           ; /* r8 = dmask */
 153         cmp     bl, 32
 154         ja      L_get_distance_code  ; /* if (32 < bits) */
 155
 156         lodsd                         ; /* eax = *(uint *)in++ */
 157         mov     cl, bl            ; /* cl = bits, needs it for shifting */
 158         add     bl, 32             ; /* bits += 32 */
 159         shl     rax, cl
 160         or      rdx, rax          ; /* hold |= *((uint *)in)++ << bits */
 161
 162 L_get_distance_code:
 163         and     r8, rdx           ; /* r8 &= hold */
 164         mov     eax, [r11+r8*4] ; /* eax = dcode[hold & dmask] */
 165
 166 L_dodist:
 167         mov     r15d, eax         ; /* dist = this */
 168         shr     r15d, 16           ; /* dist = this.val */
 169         mov     cl, ah
 170         sub     bl, ah            ; /* bits -= this.bits */
 171         shr     rdx, cl           ; /* hold >>= this.bits */
 172         mov     cl, al            ; /* cl = this.op */
 173
 174         test    al, 16             ; /* if ((op & 16) == 0) */
 175         jz      L_test_for_second_level_dist
 176         and     cl, 15             ; /* op &= 15 */
 177         jz      L_check_dist_one
 178
 179 L_add_bits_to_dist:
 180         sub     bl, cl
 181         xor     eax, eax
 182         inc     eax
 183         shl     eax, cl
 184         dec     eax                 ; /* (1 << op) - 1 */
 185         and     eax, edx          ; /* eax &= hold */
 186         shr     rdx, cl
 187         add     r15d, eax         ; /* dist += hold & ((1 << op) - 1) */
 188
 189 L_check_window:
 190         mov     r8, rsi           ; /* save in so from can use it's reg */
 191         mov     rax, rdi
 192         sub     rax, [rsp+40]      ; /* nbytes = out - beg */
 193
 194         cmp     eax, r15d
 195         jb      L_clip_window        ; /* if (dist > nbytes) 4.2% */
 196
 197         mov     ecx, r14d         ; /* ecx = len */
 198         mov     rsi, rdi
 199         sub     rsi, r15          ; /* from = out - dist */
 200
 201         sar     ecx, 1
 202         jnc     L_copy_two           ; /* if len % 2 == 0 */
 203
 204         rep     movsw
 205         mov     al, [rsi]
 206         mov     [rdi], al
 207         inc     rdi
 208
 209         mov     rsi, r8           ; /* move in back to %rsi, toss from */
 210         jmp     L_while_test
 211
 212 L_copy_two:
 213         rep     movsw
 214         mov     rsi, r8           ; /* move in back to %rsi, toss from */
 215         jmp     L_while_test
 216
 217 ALIGN 4
 218 L_check_dist_one:
 219         cmp     r15d, 1            ; /* if dist 1, is a memset */
 220         jne     L_check_window
 221         cmp     [rsp+40], rdi      ; /* if out == beg, outside window */
 222         je      L_check_window
 223
 224         mov     ecx, r14d         ; /* ecx = len */
 225         mov     al, [rdi-1]
 226         mov     ah, al
 227
 228         sar     ecx, 1
 229         jnc     L_set_two
 230         mov     [rdi], al
 231         inc     rdi
 232
 233 L_set_two:
 234         rep     stosw
 235         jmp     L_while_test
 236
 237 ALIGN 4
 238 L_test_for_second_level_length:
 239         test    al, 64
 240         jnz     L_test_for_end_of_block ; /* if ((op & 64) != 0) */
 241
 242         xor     eax, eax
 243         inc     eax
 244         shl     eax, cl
 245         dec     eax
 246         and     eax, edx         ; /* eax &= hold */
 247         add     eax, r14d        ; /* eax += len */
 248         mov     eax, [rbp+rax*4] ; /* eax = lcode[val+(hold&mask[op])]*/
 249         jmp     L_dolen
 250
 251 ALIGN 4
 252 L_test_for_second_level_dist:
 253         test    al, 64
 254         jnz     L_invalid_distance_code ; /* if ((op & 64) != 0) */
 255
 256         xor     eax, eax
 257         inc     eax
 258         shl     eax, cl
 259         dec     eax
 260         and     eax, edx         ; /* eax &= hold */
 261         add     eax, r15d        ; /* eax += dist */
 262         mov     eax, [r11+rax*4] ; /* eax = dcode[val+(hold&mask[op])]*/
 263         jmp     L_dodist
 264
 265 ALIGN 4
 266 L_clip_window:
 267         mov     ecx, eax         ; /* ecx = nbytes */
 268         mov     eax, [rsp+92]     ; /* eax = wsize, prepare for dist cmp */
 269         neg     ecx                ; /* nbytes = -nbytes */
 270
 271         cmp     eax, r15d
 272         jb      L_invalid_distance_too_far ; /* if (dist > wsize) */
 273
 274         add     ecx, r15d         ; /* nbytes = dist - nbytes */
 275         cmp     dword ptr [rsp+96], 0
 276         jne     L_wrap_around_window ; /* if (write != 0) */
 277
 278         mov     rsi, [rsp+56]     ; /* from  = window */
 279         sub     eax, ecx         ; /* eax  -= nbytes */
 280         add     rsi, rax         ; /* from += wsize - nbytes */
 281
 282         mov     eax, r14d        ; /* eax = len */
 283         cmp     r14d, ecx
 284         jbe     L_do_copy           ; /* if (nbytes >= len) */
 285
 286         sub     eax, ecx         ; /* eax -= nbytes */
 287         rep     movsb
 288         mov     rsi, rdi
 289         sub     rsi, r15         ; /* from = &out[ -dist ] */
 290         jmp     L_do_copy
 291
 292 ALIGN 4
 293 L_wrap_around_window:
 294         mov     eax, [rsp+96]     ; /* eax = write */
 295         cmp     ecx, eax
 296         jbe     L_contiguous_in_window ; /* if (write >= nbytes) */
 297
 298         mov     esi, [rsp+92]     ; /* from  = wsize */
 299         add     rsi, [rsp+56]     ; /* from += window */
 300         add     rsi, rax         ; /* from += write */
 301         sub     rsi, rcx         ; /* from -= nbytes */
 302         sub     ecx, eax         ; /* nbytes -= write */
 303
 304         mov     eax, r14d        ; /* eax = len */
 305         cmp     eax, ecx
 306         jbe     L_do_copy           ; /* if (nbytes >= len) */
 307
 308         sub     eax, ecx         ; /* len -= nbytes */
 309         rep     movsb
 310         mov     rsi, [rsp+56]     ; /* from = window */
 311         mov     ecx, [rsp+96]     ; /* nbytes = write */
 312         cmp     eax, ecx
 313         jbe     L_do_copy           ; /* if (nbytes >= len) */
 314
 315         sub     eax, ecx         ; /* len -= nbytes */
 316         rep     movsb
 317         mov     rsi, rdi
 318         sub     rsi, r15         ; /* from = out - dist */
 319         jmp     L_do_copy
 320
 321 ALIGN 4
 322 L_contiguous_in_window:
 323         mov     rsi, [rsp+56]     ; /* rsi = window */
 324         add     rsi, rax
 325         sub     rsi, rcx         ; /* from += write - nbytes */
 326
 327         mov     eax, r14d        ; /* eax = len */
 328         cmp     eax, ecx
 329         jbe     L_do_copy           ; /* if (nbytes >= len) */
 330
 331         sub     eax, ecx         ; /* len -= nbytes */
 332         rep     movsb
 333         mov     rsi, rdi
 334         sub     rsi, r15         ; /* from = out - dist */
 335         jmp     L_do_copy           ; /* if (nbytes >= len) */
 336
 337 ALIGN 4
 338 L_do_copy:
 339         mov     ecx, eax         ; /* ecx = len */
 340         rep     movsb
 341
 342         mov     rsi, r8          ; /* move in back to %esi, toss from */
 343         jmp     L_while_test
 344
 345 L_test_for_end_of_block:
 346         test    al, 32
 347         jz      L_invalid_literal_length_code
 348         mov     dword ptr [rsp+116], 1
 349         jmp     L_break_loop_with_status
 350
 351 L_invalid_literal_length_code:
 352         mov     dword ptr [rsp+116], 2
 353         jmp     L_break_loop_with_status
 354
 355 L_invalid_distance_code:
 356         mov     dword ptr [rsp+116], 3
 357         jmp     L_break_loop_with_status
 358
 359 L_invalid_distance_too_far:
 360         mov     dword ptr [rsp+116], 4
 361         jmp     L_break_loop_with_status
 362
 363 L_break_loop:
 364         mov     dword ptr [rsp+116], 0
 365
 366 L_break_loop_with_status:
 367 ; /* put in, out, bits, and hold back into ar and pop esp */
 368         mov     [rsp+16], rsi     ; /* in */
 369         mov     [rsp+32], rdi     ; /* out */
 370         mov     [rsp+88], ebx     ; /* bits */
 371         mov     [rsp+80], rdx     ; /* hold */
 372
 373         mov     rax, [rsp]       ; /* restore rbp and rsp */
 374         mov     rbp, [rsp+8]
 375         mov     rsp, rax
 376
 377
 378
 379         mov rsi,[rsp-8]
 380         mov rdi,[rsp-16]
 381         mov r12,[rsp-24]
 382         mov r13,[rsp-32]
 383         mov r14,[rsp-40]
 384         mov r15,[rsp-48]
 385         mov rbx,[rsp-56]
 386
 387     ret 0
 388 ;          :
 389 ;          : "m" (ar)
 390 ;          : "memory", "%rax", "%rbx", "%rcx", "%rdx", "%rsi", "%rdi",
 391 ;            "%r8", "%r9", "%r10", "%r11", "%r12", "%r13", "%r14", "%r15"
 392 ;    );
 393
 394 inffas8664fnc   ENDP
 395 ;_TEXT  ENDS
 396 END