/* inffas86.c is a hand tuned assembler version of * * inffast.c -- fast decoding * Copyright (C) 1995-2003 Mark Adler * For conditions of distribution and use, see copyright notice in zlib.h * * Copyright (C) 2003 Chris Anderson <christop@charm.net> * Please use the copyright conditions above. * * Dec-29-2003 -- I added AMD64 inflate asm support.  This version is also * slightly quicker on x86 systems because, instead of using rep movsb to copy * data, it uses rep movsw, which moves data in 2-byte chunks instead of single * bytes.  I've tested the AMD64 code on a Fedora Core 1 + the x86_64 updates * from http://fedora.linux.duke.edu/fc1_x86_64 * which is running on an Athlon 64 3000+ / Gigabyte GA-K8VT800M system with * 1GB ram.  The 64-bit version is about 4% faster than the 32-bit version, * when decompressing mozilla-source-1.3.tar.gz. * * Mar-13-2003 -- Most of this is derived from inffast.S which is derived from * the gcc -S output of zlib-1.2.0/inffast.c.  Zlib-1.2.0 is in beta release at * the moment.  I have successfully compiled and tested this code with gcc2.96, * gcc3.2, icc5.0, msvc6.0.  It is very close to the speed of inffast.S * compiled with gcc -DNO_MMX, but inffast.S is still faster on the P3 with MMX * enabled.  I will attempt to merge the MMX code into this version.  Newer * versions of this and inffast.S can be found at * http://www.eetbeetee.com/zlib/ and http://www.charm.net/~christop/zlib/ */#include "zutil.h"#include "inftrees.h"#include "inflate.h"#include "inffast.h"/* Mark Adler's comments from inffast.c: *//*   Decode literal, length, and distance codes and write out the resulting   literal and match bytes until either not enough input or output is   available, an end-of-block is encountered, or a data error is encountered.   When large enough input and output buffers are supplied to inflate(), for   example, a 16K input buffer and a 64K output buffer, more than 95% of the   inflate execution time is spent in this routine.   Entry assumptions:        state->mode == LEN        strm->avail_in >= 6        strm->avail_out >= 258        start >= strm->avail_out        state->bits < 8   On return, state->mode is one of:        LEN -- ran out of enough output space or enough available input        TYPE -- reached end of block code, inflate() to interpret next block        BAD -- error in block data   Notes:    - The maximum input bits used by a length/distance pair is 15 bits for the      length code, 5 bits for the length extra, 15 bits for the distance code,      and 13 bits for the distance extra.  This totals 48 bits, or six bytes.      Therefore if strm->avail_in >= 6, then there is enough input to avoid      checking for available input while decoding.    - The maximum bytes that a single length/distance pair can output is 258      bytes, which is the maximum length that can be coded.  inflate_fast()      requires strm->avail_out >= 258 for each loop to avoid checking for      output space. */void inflate_fast(strm, start)z_streamp strm;unsigned start;         /* inflate()'s starting value for strm->avail_out */{    struct inflate_state FAR *state;    struct inffast_ar {/* 64   32                               x86  x86_64 *//* ar offset                              register *//*  0    0 */ void *esp;                /* esp save *//*  8    4 */ void *ebp;                /* ebp save *//* 16    8 */ unsigned char FAR *in;    /* esi rsi  local strm->next_in *//* 24   12 */ unsigned char FAR *last;  /*     r9   while in < last *//* 32   16 */ unsigned char FAR *out;   /* edi rdi  local strm->next_out *//* 40   20 */ unsigned char FAR *beg;   /*          inflate()'s init next_out *//* 48   24 */ unsigned char FAR *end;   /*     r10  while out < end *//* 56   28 */ unsigned char FAR *window;/*          size of window, wsize!=0 *//* 64   32 */ code const FAR *lcode;    /* ebp rbp  local strm->lencode *//* 72   36 */ code const FAR *dcode;    /*     r11  local strm->distcode *//* 80   40 */ unsigned long hold;       /* edx rdx  local strm->hold *//* 88   44 */ unsigned bits;            /* ebx rbx  local strm->bits *//* 92   48 */ unsigned wsize;           /*          window size *//* 96   52 */ unsigned write;           /*          window write index *//*100   56 */ unsigned lmask;           /*     r12  mask for lcode *//*104   60 */ unsigned dmask;           /*     r13  mask for dcode *//*108   64 */ unsigned len;             /*     r14  match length *//*112   68 */ unsigned dist;            /*     r15  match distance *//*116   72 */ unsigned status;          /*          set when state chng*/    } ar;#if defined( __GNUC__ ) && defined( __amd64__ ) && ! defined( __i386 )#define PAD_AVAIL_IN 6#define PAD_AVAIL_OUT 258#else#define PAD_AVAIL_IN 5#define PAD_AVAIL_OUT 257#endif    /* copy state to local variables */    state = (struct inflate_state FAR *)strm->state;    ar.in = strm->next_in;    ar.last = ar.in + (strm->avail_in - PAD_AVAIL_IN);    ar.out = strm->next_out;    ar.beg = ar.out - (start - strm->avail_out);    ar.end = ar.out + (strm->avail_out - PAD_AVAIL_OUT);    ar.wsize = state->wsize;    ar.write = state->write;    ar.window = state->window;    ar.hold = state->hold;    ar.bits = state->bits;    ar.lcode = state->lencode;    ar.dcode = state->distcode;    ar.lmask = (1U << state->lenbits) - 1;    ar.dmask = (1U << state->distbits) - 1;    /* decode literals and length/distances until end-of-block or not enough       input data or output space */    /* align in on 1/2 hold size boundary */    while (((unsigned long)(void *)ar.in & (sizeof(ar.hold) / 2 - 1)) != 0) {        ar.hold += (unsigned long)*ar.in++ << ar.bits;        ar.bits += 8;    }#if defined( __GNUC__ ) && defined( __amd64__ ) && ! defined( __i386 )    __asm__ __volatile__ ("        leaq    %0, %%rax\n""        movq    %%rbp, 8(%%rax)\n"       /* save regs rbp and rsp */"        movq    %%rsp, (%%rax)\n""        movq    %%rax, %%rsp\n"          /* make rsp point to &ar */"        movq    16(%%rsp), %%rsi\n"      /* rsi  = in */"        movq    32(%%rsp), %%rdi\n"      /* rdi  = out */"        movq    24(%%rsp), %%r9\n"       /* r9   = last */"        movq    48(%%rsp), %%r10\n"      /* r10  = end */"        movq    64(%%rsp), %%rbp\n"      /* rbp  = lcode */"        movq    72(%%rsp), %%r11\n"      /* r11  = dcode */"        movq    80(%%rsp), %%rdx\n"      /* rdx  = hold */"        movl    88(%%rsp), %%ebx\n"      /* ebx  = bits */"        movl    100(%%rsp), %%r12d\n"    /* r12d = lmask */"        movl    104(%%rsp), %%r13d\n"    /* r13d = dmask */                                          /* r14d = len */                                          /* r15d = dist */"        cld\n""        cmpq    %%rdi, %%r10\n""        je      .L_one_time\n"           /* if only one decode left */"        cmpq    %%rsi, %%r9\n""        je      .L_one_time\n""        jmp     .L_do_loop\n"".L_one_time:\n""        movq    %%r12, %%r8\n"           /* r8 = lmask */"        cmpb    $32, %%bl\n""        ja      .L_get_length_code_one_time\n""        lodsl\n"                         /* eax = *(uint *)in++ */"        movb    %%bl, %%cl\n"            /* cl = bits, needs it for shifting */"        addb    $32, %%bl\n"             /* bits += 32 */"        shlq    %%cl, %%rax\n""        orq     %%rax, %%rdx\n"          /* hold |= *((uint *)in)++ << bits */"        jmp     .L_get_length_code_one_time\n"".align 32,0x90\n"".L_while_test:\n""        cmpq    %%rdi, %%r10\n""        jbe     .L_break_loop\n""        cmpq    %%rsi, %%r9\n""        jbe     .L_break_loop\n"".L_do_loop:\n""        movq    %%r12, %%r8\n"           /* r8 = lmask */"        cmpb    $32, %%bl\n""        ja      .L_get_length_code\n"    /* if (32 < bits) */"        lodsl\n"                         /* eax = *(uint *)in++ */"        movb    %%bl, %%cl\n"            /* cl = bits, needs it for shifting */"        addb    $32, %%bl\n"             /* bits += 32 */"        shlq    %%cl, %%rax\n""        orq     %%rax, %%rdx\n"          /* hold |= *((uint *)in)++ << bits */".L_get_length_code:\n""        andq    %%rdx, %%r8\n"            /* r8 &= hold */"        movl    (%%rbp,%%r8,4), %%eax\n"  /* eax = lcode[hold & lmask] */"        movb    %%ah, %%cl\n"            /* cl = this.bits */"        subb    %%ah, %%bl\n"            /* bits -= this.bits */"        shrq    %%cl, %%rdx\n"           /* hold >>= this.bits */"        testb   %%al, %%al\n""        jnz     .L_test_for_length_base\n" /* if (op != 0) 45.7% */"        movq    %%r12, %%r8\n"            /* r8 = lmask */"        shrl    $16, %%eax\n"            /* output this.val char */"        stosb\n"".L_get_length_code_one_time:\n""        andq    %%rdx, %%r8\n"            /* r8 &= hold */"        movl    (%%rbp,%%r8,4), %%eax\n" /* eax = lcode[hold & lmask] */".L_dolen:\n""        movb    %%ah, %%cl\n"            /* cl = this.bits */"        subb    %%ah, %%bl\n"            /* bits -= this.bits */"        shrq    %%cl, %%rdx\n"           /* hold >>= this.bits */"        testb   %%al, %%al\n""        jnz     .L_test_for_length_base\n" /* if (op != 0) 45.7% */"        shrl    $16, %%eax\n"            /* output this.val char */"        stosb\n""        jmp     .L_while_test\n"".align 32,0x90\n"".L_test_for_length_base:\n""        movl    %%eax, %%r14d\n"         /* len = this */"        shrl    $16, %%r14d\n"           /* len = this.val */"        movb    %%al, %%cl\n""        testb   $16, %%al\n""        jz      .L_test_for_second_level_length\n" /* if ((op & 16) == 0) 8% */"        andb    $15, %%cl\n"             /* op &= 15 */"        jz      .L_decode_distance\n"    /* if (!op) */".L_add_bits_to_len:\n""        subb    %%cl, %%bl\n""        xorl    %%eax, %%eax\n""        incl    %%eax\n""        shll    %%cl, %%eax\n""        decl    %%eax\n""        andl    %%edx, %%eax\n"          /* eax &= hold */"        shrq    %%cl, %%rdx\n""        addl    %%eax, %%r14d\n"         /* len += hold & mask[op] */".L_decode_distance:\n""        movq    %%r13, %%r8\n"           /* r8 = dmask */"        cmpb    $32, %%bl\n""        ja      .L_get_distance_code\n"  /* if (32 < bits) */"        lodsl\n"                         /* eax = *(uint *)in++ */"        movb    %%bl, %%cl\n"            /* cl = bits, needs it for shifting */"        addb    $32, %%bl\n"             /* bits += 32 */"        shlq    %%cl, %%rax\n""        orq     %%rax, %%rdx\n"          /* hold |= *((uint *)in)++ << bits */".L_get_distance_code:\n""        andq    %%rdx, %%r8\n"           /* r8 &= hold */"        movl    (%%r11,%%r8,4), %%eax\n" /* eax = dcode[hold & dmask] */".L_dodist:\n""        movl    %%eax, %%r15d\n"         /* dist = this */"        shrl    $16, %%r15d\n"           /* dist = this.val */"        movb    %%ah, %%cl\n""        subb    %%ah, %%bl\n"            /* bits -= this.bits */"        shrq    %%cl, %%rdx\n"           /* hold >>= this.bits */"        movb    %%al, %%cl\n"            /* cl = this.op */"        testb   $16, %%al\n"             /* if ((op & 16) == 0) */"        jz      .L_test_for_second_level_dist\n""        andb    $15, %%cl\n"             /* op &= 15 */"        jz      .L_check_dist_one\n"".L_add_bits_to_dist:\n""        subb    %%cl, %%bl\n""        xorl    %%eax, %%eax\n""        incl    %%eax\n""        shll    %%cl, %%eax\n""        decl    %%eax\n"                 /* (1 << op) - 1 */"        andl    %%edx, %%eax\n"          /* eax &= hold */"        shrq    %%cl, %%rdx\n""        addl    %%eax, %%r15d\n"         /* dist += hold & ((1 << op) - 1) */".L_check_window:\n""        movq    %%rsi, %%r8\n"           /* save in so from can use it's reg */"        movq    %%rdi, %%rax\n""        subq    40(%%rsp), %%rax\n"      /* nbytes = out - beg */"        cmpl    %%r15d, %%eax\n""        jb      .L_clip_window\n"        /* if (dist > nbytes) 4.2% */"        movl    %%r14d, %%ecx\n"         /* ecx = len */"        movq    %%rdi, %%rsi\n""        subq    %%r15, %%rsi\n"          /* from = out - dist */"        sarl    %%ecx\n""        jnc     .L_copy_two\n"           /* if len % 2 == 0 */"        rep     movsw\n""        movb    (%%rsi), %%al\n""        movb    %%al, (%%rdi)\n""        incq    %%rdi\n""        movq    %%r8, %%rsi\n"           /* move in back to %rsi, toss from */"        jmp     .L_while_test\n"".L_copy_two:\n""        rep     movsw\n""        movq    %%r8, %%rsi\n"           /* move in back to %rsi, toss from */"        jmp     .L_while_test\n"".align 32,0x90\n"".L_check_dist_one:\n""        cmpl    $1, %%r15d\n"            /* if dist 1, is a memset */"        jne     .L_check_window\n""        cmpq    %%rdi, 40(%%rsp)\n"      /* if out == beg, outside window */"        je      .L_check_window\n""        movl    %%r14d, %%ecx\n"         /* ecx = len */"        movb    -1(%%rdi), %%al\n""        movb    %%al, %%ah\n""        sarl    %%ecx\n""        jnc     .L_set_two\n""        movb    %%al, (%%rdi)\n""        incq    %%rdi\n"".L_set_two:\n""        rep     stosw\n""        jmp     .L_while_test\n"".align 32,0x90\n"".L_test_for_second_level_length:\n""        testb   $64, %%al\n""        jnz     .L_test_for_end_of_block\n" /* if ((op & 64) != 0) */"        xorl    %%eax, %%eax\n""        incl    %%eax\n""        shll    %%cl, %%eax\n""        decl    %%eax\n""        andl    %%edx, %%eax\n"         /* eax &= hold */"        addl    %%r14d, %%eax\n"        /* eax += len */"        movl    (%%rbp,%%rax,4), %%eax\n" /* eax = lcode[val+(hold&mask[op])]*/"        jmp     .L_dolen\n"".align 32,0x90\n"".L_test_for_second_level_dist:\n""        testb   $64, %%al\n""        jnz     .L_invalid_distance_code\n" /* if ((op & 64) != 0) */"        xorl    %%eax, %%eax\n""        incl    %%eax\n""        shll    %%cl, %%eax\n""        decl    %%eax\n""        andl    %%edx, %%eax\n"         /* eax &= hold */"        addl    %%r15d, %%eax\n"        /* eax += dist */"        movl    (%%r11,%%rax,4), %%eax\n" /* eax = dcode[val+(hold&mask[op])]*/"        jmp     .L_dodist\n"".align 32,0x90\n"".L_clip_window:\n""        movl    %%eax, %%ecx\n"         /* ecx = nbytes */"        movl    92(%%rsp), %%eax\n"     /* eax = wsize, prepare for dist cmp */"        negl    %%ecx\n"                /* nbytes = -nbytes */"        cmpl    %%r15d, %%eax\n""        jb      .L_invalid_distance_too_far\n" /* if (dist > wsize) */"        addl    %%r15d, %%ecx\n"         /* nbytes = dist - nbytes */"        cmpl    $0, 96(%%rsp)\n""        jne     .L_wrap_around_window\n" /* if (write != 0) */"        movq    56(%%rsp), %%rsi\n"     /* from  = window */"        subl    %%ecx, %%eax\n"         /* eax  -= nbytes */"        addq    %%rax, %%rsi\n"         /* from += wsize - nbytes */"        movl    %%r14d, %%eax\n"        /* eax = len */"        cmpl    %%ecx, %%r14d\n""        jbe     .L_do_copy\n"           /* if (nbytes >= len) */"        subl    %%ecx, %%eax\n"         /* eax -= nbytes */"        rep     movsb\n""        movq    %%rdi, %%rsi\n""        subq    %%r15, %%rsi\n"         /* from = &out[ -dist ] */"        jmp     .L_do_copy\n"".align 32,0x90\n"".L_wrap_around_window:\n""        movl    96(%%rsp), %%eax\n"     /* eax = write */"        cmpl    %%eax, %%ecx\n""        jbe     .L_contiguous_in_window\n" /* if (write >= nbytes) */