| /* 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. |
| * |
| * 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 { |
| void *esp; /* esp save */ |
| unsigned char FAR *in; /* local strm->next_in */ |
| unsigned char FAR *last; /* while in < last, enough input available */ |
| unsigned char FAR *out; /* local strm->next_out */ |
| unsigned char FAR *beg; /* inflate()'s initial strm->next_out */ |
| unsigned char FAR *end; /* while out < end, enough space available */ |
| unsigned wsize; /* window size or zero if not using window */ |
| unsigned write; /* window write index */ |
| unsigned char FAR *window; /* allocated sliding window, if wsize != 0 */ |
| unsigned long hold; /* local strm->hold */ |
| unsigned bits; /* local strm->bits */ |
| code const FAR *lcode; /* local strm->lencode */ |
| code const FAR *dcode; /* local strm->distcode */ |
| unsigned lmask; /* mask for first level of length codes */ |
| unsigned dmask; /* mask for first level of distance codes */ |
| unsigned len; /* match length, unused bytes */ |
| unsigned dist; /* match distance */ |
| unsigned status; /* this is set when state changes */ |
| } ar; |
| |
| /* copy state to local variables */ |
| state = (struct inflate_state FAR *)strm->state; |
| ar.in = strm->next_in; |
| ar.last = ar.in + (strm->avail_in - 5); |
| ar.out = strm->next_out; |
| ar.beg = ar.out - (start - strm->avail_out); |
| ar.end = ar.out + (strm->avail_out - 257); |
| 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 2 byte boundary */ |
| if (((unsigned long)(void *)ar.in & 0x1) != 0) { |
| ar.hold += (unsigned long)*ar.in++ << ar.bits; |
| ar.bits += 8; |
| } |
| |
| #if defined( __GNUC__ ) || defined( __ICC ) |
| __asm__ __volatile__ ( |
| " leal %0, %%eax\n" |
| " pushf\n" |
| " pushl %%ebp\n" |
| " movl %%esp, (%%eax)\n" |
| " movl %%eax, %%esp\n" |
| " movl 4(%%esp), %%esi\n" /* esi = in */ |
| " movl 12(%%esp), %%edi\n" /* edi = out */ |
| " movl 36(%%esp), %%edx\n" /* edx = hold */ |
| " movl 40(%%esp), %%ebx\n" /* ebx = bits */ |
| " movl 44(%%esp), %%ebp\n" /* ebp = lcode */ |
| |
| " cld\n" |
| " jmp .L_do_loop\n" |
| |
| ".L_while_test:\n" |
| " cmpl %%edi, 20(%%esp)\n" |
| " jbe .L_break_loop\n" |
| " cmpl %%esi, 8(%%esp)\n" |
| " jbe .L_break_loop\n" |
| |
| ".L_do_loop:\n" |
| " cmpb $15, %%bl\n" |
| " ja .L_get_length_code\n" /* if (15 < bits) */ |
| |
| " xorl %%eax, %%eax\n" |
| " lodsw\n" /* al = *(ushort *)in++ */ |
| " movb %%bl, %%cl\n" /* cl = bits, needs it for shifting */ |
| " addb $16, %%bl\n" /* bits += 16 */ |
| " shll %%cl, %%eax\n" |
| " orl %%eax, %%edx\n" /* hold |= *((ushort *)in)++ << bits */ |
| |
| ".L_get_length_code:\n" |
| " movl 52(%%esp), %%eax\n" /* eax = lmask */ |
| " andl %%edx, %%eax\n" /* eax &= hold */ |
| " movl (%%ebp,%%eax,4), %%eax\n" /* eax = lcode[hold & lmask] */ |
| |
| ".L_dolen:\n" |
| " movb %%ah, %%cl\n" /* cl = this.bits */ |
| " subb %%ah, %%bl\n" /* bits -= this.bits */ |
| " shrl %%cl, %%edx\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" |
| |
| ".L_test_for_length_base:\n" |
| " movl %%eax, %%ecx\n" /* len = this */ |
| " shrl $16, %%ecx\n" /* len = this.val */ |
| " movl %%ecx, 60(%%esp)\n" /* len = this */ |
| " 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) */ |
| " cmpb %%cl, %%bl\n" |
| " jae .L_add_bits_to_len\n" /* if (op <= bits) */ |
| |
| " movb %%cl, %%ch\n" /* stash op in ch, freeing cl */ |
| " xorl %%eax, %%eax\n" |
| " lodsw\n" /* al = *(ushort *)in++ */ |
| " movb %%bl, %%cl\n" /* cl = bits, needs it for shifting */ |
| " addb $16, %%bl\n" /* bits += 16 */ |
| " shll %%cl, %%eax\n" |
| " orl %%eax, %%edx\n" /* hold |= *((ushort *)in)++ << bits */ |
| " movb %%ch, %%cl\n" /* move op back to ecx */ |
| |
| ".L_add_bits_to_len:\n" |
| " movl $1, %%eax\n" |
| " shll %%cl, %%eax\n" |
| " decl %%eax\n" |
| " subb %%cl, %%bl\n" |
| " andl %%edx, %%eax\n" /* eax &= hold */ |
| " shrl %%cl, %%edx\n" |
| " addl %%eax, 60(%%esp)\n" /* len += hold & mask[op] */ |
| |
| ".L_decode_distance:\n" |
| " cmpb $15, %%bl\n" |
| " ja .L_get_distance_code\n" /* if (15 < bits) */ |
| |
| " xorl %%eax, %%eax\n" |
| " lodsw\n" /* al = *(ushort *)in++ */ |
| " movb %%bl, %%cl\n" /* cl = bits, needs it for shifting */ |
| " addb $16, %%bl\n" /* bits += 16 */ |
| " shll %%cl, %%eax\n" |
| " orl %%eax, %%edx\n" /* hold |= *((ushort *)in)++ << bits */ |
| |
| ".L_get_distance_code:\n" |
| " movl 56(%%esp), %%eax\n" /* eax = dmask */ |
| " movl 48(%%esp), %%ecx\n" /* ecx = dcode */ |
| " andl %%edx, %%eax\n" /* eax &= hold */ |
| " movl (%%ecx,%%eax,4), %%eax\n"/* eax = dcode[hold & dmask] */ |
| |
| ".L_dodist:\n" |
| " movl %%eax, %%ebp\n" /* dist = this */ |
| " shrl $16, %%ebp\n" /* dist = this.val */ |
| " movb %%ah, %%cl\n" |
| " subb %%ah, %%bl\n" /* bits -= this.bits */ |
| " shrl %%cl, %%edx\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" |
| " cmpb %%cl, %%bl\n" |
| " jae .L_add_bits_to_dist\n" /* if (op <= bits) 97.6% */ |
| |
| " movb %%cl, %%ch\n" /* stash op in ch, freeing cl */ |
| " xorl %%eax, %%eax\n" |
| " lodsw\n" /* al = *(ushort *)in++ */ |
| " movb %%bl, %%cl\n" /* cl = bits, needs it for shifting */ |
| " addb $16, %%bl\n" /* bits += 16 */ |
| " shll %%cl, %%eax\n" |
| " orl %%eax, %%edx\n" /* hold |= *((ushort *)in)++ << bits */ |
| " movb %%ch, %%cl\n" /* move op back to ecx */ |
| |
| ".L_add_bits_to_dist:\n" |
| " movl $1, %%eax\n" |
| " shll %%cl, %%eax\n" |
| " decl %%eax\n" /* (1 << op) - 1 */ |
| " subb %%cl, %%bl\n" |
| " andl %%edx, %%eax\n" /* eax &= hold */ |
| " shrl %%cl, %%edx\n" |
| " addl %%eax, %%ebp\n" /* dist += hold & ((1 << op) - 1) */ |
| |
| ".L_check_window:\n" |
| " movl %%esi, 4(%%esp)\n" /* save in so from can use it's reg */ |
| " movl %%edi, %%eax\n" |
| " subl 16(%%esp), %%eax\n" /* nbytes = out - beg */ |
| |
| " cmpl %%ebp, %%eax\n" |
| " jb .L_clip_window\n" /* if (dist > nbytes) 4.2% */ |
| |
| " movl 60(%%esp), %%ecx\n" |
| " movl %%edi, %%esi\n" |
| " subl %%ebp, %%esi\n" /* from = out - dist */ |
| |
| " subl $3, %%ecx\n" /* copy from to out */ |
| " movb (%%esi), %%al\n" |
| " movb %%al, (%%edi)\n" |
| " movb 1(%%esi), %%al\n" |
| " movb 2(%%esi), %%ah\n" |
| " addl $3, %%esi\n" |
| " movb %%al, 1(%%edi)\n" |
| " movb %%ah, 2(%%edi)\n" |
| " addl $3, %%edi\n" |
| " rep movsb\n" |
| |
| " movl 4(%%esp), %%esi\n" /* move in back to %esi, toss from */ |
| " movl 44(%%esp), %%ebp\n" /* ebp = lcode */ |
| " jmp .L_while_test\n" |
| |
| ".L_check_dist_one:\n" |
| " cmpl $1, %%ebp\n" /* if dist 1, is a memset */ |
| " jne .L_check_window\n" |
| " cmpl %%edi, 16(%%esp)\n" |
| " je .L_check_window\n" |
| |
| " decl %%edi\n" |
| " movl 60(%%esp), %%ecx\n" |
| " movb (%%edi), %%al\n" |
| " subl $3, %%ecx\n" |
| |
| " movb %%al, 1(%%edi)\n" /* memset out with from[-1] */ |
| " movb %%al, 2(%%edi)\n" |
| " movb %%al, 3(%%edi)\n" |
| " addl $4, %%edi\n" |
| " rep stosb\n" |
| " movl 44(%%esp), %%ebp\n" /* ebp = lcode */ |
| " jmp .L_while_test\n" |
| |
| ".L_test_for_second_level_length:\n" |
| " testb $64, %%al\n" |
| " jnz .L_test_for_end_of_block\n" /* if ((op & 64) != 0) */ |
| |
| " movl $1, %%eax\n" |
| " shll %%cl, %%eax\n" |
| " decl %%eax\n" |
| " andl %%edx, %%eax\n" /* eax &= hold */ |
| " addl 60(%%esp), %%eax\n" /* eax += this.val */ |
| " movl (%%ebp,%%eax,4), %%eax\n" /* eax = lcode[val+(hold&mask[op])]*/ |
| " jmp .L_dolen\n" |
| |
| ".L_test_for_second_level_dist:\n" |
| " testb $64, %%al\n" |
| " jnz .L_invalid_distance_code\n" /* if ((op & 64) != 0) */ |
| |
| " movl $1, %%eax\n" |
| " shll %%cl, %%eax\n" |
| " decl %%eax\n" |
| " andl %%edx, %%eax\n" /* eax &= hold */ |
| " addl %%ebp, %%eax\n" /* eax += this.val */ |
| " movl 48(%%esp), %%ecx\n" /* ecx = dcode */ |
| " movl (%%ecx,%%eax,4), %%eax\n" /* eax = dcode[val+(hold&mask[op])]*/ |
| " jmp .L_dodist\n" |
| |
| ".L_clip_window:\n" |
| " movl %%eax, %%ecx\n" |
| " movl 24(%%esp), %%eax\n" /* prepare for dist compare */ |
| " negl %%ecx\n" /* nbytes = -nbytes */ |
| " movl 32(%%esp), %%esi\n" /* from = window */ |
| |
| " cmpl %%ebp, %%eax\n" |
| " jb .L_invalid_distance_too_far\n" /* if (dist > wsize) */ |
| |
| " addl %%ebp, %%ecx\n" /* nbytes = dist - nbytes */ |
| " cmpl $0, 28(%%esp)\n" |
| " jne .L_wrap_around_window\n" /* if (write != 0) */ |
| |
| " subl %%ecx, %%eax\n" |
| " addl %%eax, %%esi\n" /* from += wsize - nbytes */ |
| |
| " movl 60(%%esp), %%eax\n" |
| " cmpl %%ecx, %%eax\n" |
| " jbe .L_do_copy1\n" /* if (nbytes >= len) */ |
| |
| " subl %%ecx, %%eax\n" /* len -= nbytes */ |
| " rep movsb\n" |
| " movl %%edi, %%esi\n" |
| " subl %%ebp, %%esi\n" /* from = out - dist */ |
| " jmp .L_do_copy1\n" |
| |
| " cmpl %%ecx, %%eax\n" |
| " jbe .L_do_copy1\n" /* if (nbytes >= len) */ |
| |
| " subl %%ecx, %%eax\n" /* len -= nbytes */ |
| " rep movsb\n" |
| " movl %%edi, %%esi\n" |
| " subl %%ebp, %%esi\n" /* from = out - dist */ |
| " jmp .L_do_copy1\n" |
| |
| ".L_wrap_around_window:\n" |
| " movl 28(%%esp), %%eax\n" |
| " cmpl %%eax, %%ecx\n" |
| " jbe .L_contiguous_in_window\n" /* if (write >= nbytes) */ |
| |
| " addl 24(%%esp), %%esi\n" |
| " addl %%eax, %%esi\n" |
| " subl %%ecx, %%esi\n" /* from += wsize + write - nbytes */ |
| " subl %%eax, %%ecx\n" /* nbytes -= write */ |
| |
| " movl 60(%%esp), %%eax\n" |
| " cmpl %%ecx, %%eax\n" |
| " jbe .L_do_copy1\n" /* if (nbytes >= len) */ |
| |
| " subl %%ecx, %%eax\n" /* len -= nbytes */ |
| " rep movsb\n" |
| " movl 32(%%esp), %%esi\n" /* from = window */ |
| " movl 28(%%esp), %%ecx\n" /* nbytes = write */ |
| " cmpl %%ecx, %%eax\n" |
| " jbe .L_do_copy1\n" /* if (nbytes >= len) */ |
| |
| " subl %%ecx, %%eax\n" /* len -= nbytes */ |
| " rep movsb\n" |
| " movl %%edi, %%esi\n" |
| " subl %%ebp, %%esi\n" /* from = out - dist */ |
| " jmp .L_do_copy1\n" |
| |
| ".L_contiguous_in_window:\n" |
| " addl %%eax, %%esi\n" |
| " subl %%ecx, %%esi\n" /* from += write - nbytes */ |
| |
| " movl 60(%%esp), %%eax\n" |
| " cmpl %%ecx, %%eax\n" |
| " jbe .L_do_copy1\n" /* if (nbytes >= len) */ |
| |
| " subl %%ecx, %%eax\n" /* len -= nbytes */ |
| " rep movsb\n" |
| " movl %%edi, %%esi\n" |
| " subl %%ebp, %%esi\n" /* from = out - dist */ |
| |
| ".L_do_copy1:\n" |
| " movl %%eax, %%ecx\n" |
| " rep movsb\n" |
| |
| " movl 4(%%esp), %%esi\n" /* move in back to %esi, toss from */ |
| " movl 44(%%esp), %%ebp\n" /* ebp = lcode */ |
| " jmp .L_while_test\n" |
| |
| ".L_test_for_end_of_block:\n" |
| " testb $32, %%al\n" |
| " jz .L_invalid_literal_length_code\n" |
| " movl $1, 68(%%esp)\n" |
| " jmp .L_break_loop_with_status\n" |
| |
| ".L_invalid_literal_length_code:\n" |
| " movl $2, 68(%%esp)\n" |
| " jmp .L_break_loop_with_status\n" |
| |
| ".L_invalid_distance_code:\n" |
| " movl $3, 68(%%esp)\n" |
| " jmp .L_break_loop_with_status\n" |
| |
| ".L_invalid_distance_too_far:\n" |
| " movl 4(%%esp), %%esi\n" |
| " movl $4, 68(%%esp)\n" |
| " jmp .L_break_loop_with_status\n" |
| |
| ".L_break_loop:\n" |
| " movl $0, 68(%%esp)\n" |
| |
| ".L_break_loop_with_status:\n" |
| /* put in, out, bits, and hold back into ar and pop esp */ |
| " movl %%esi, 4(%%esp)\n" |
| " movl %%edi, 12(%%esp)\n" |
| " movl %%ebx, 40(%%esp)\n" |
| " movl %%edx, 36(%%esp)\n" |
| " movl (%%esp), %%esp\n" |
| " popl %%ebp\n" |
| " popf\n" |
| : |
| : "m" (ar) |
| : "memory", "%eax", "%ebx", "%ecx", "%edx", "%esi", "%edi" |
| ); |
| #elif defined( _MSC_VER ) |
| __asm { |
| lea eax, ar |
| pushfd |
| push ebp |
| mov [eax], esp |
| mov esp, eax |
| mov esi, [esp+4] /* esi = in */ |
| mov edi, [esp+12] /* edi = out */ |
| mov edx, [esp+36] /* edx = hold */ |
| mov ebx, [esp+40] /* ebx = bits */ |
| mov ebp, [esp+44] /* ebp = lcode */ |
| |
| cld |
| jmp L_do_loop |
| |
| L_while_test: |
| cmp [esp+20], edi |
| jbe L_break_loop |
| cmp [esp+8], esi |
| jbe L_break_loop |
| |
| L_do_loop: |
| cmp bl, 15 |
| ja L_get_length_code /* if (15 < bits) */ |
| |
| xor eax, eax |
| lodsw /* al = *(ushort *)in++ */ |
| mov cl, bl /* cl = bits, needs it for shifting */ |
| add bl, 16 /* bits += 16 */ |
| shl eax, cl |
| or edx, eax /* hold |= *((ushort *)in)++ << bits */ |
| |
| L_get_length_code: |
| mov eax, [esp+52] /* eax = lmask */ |
| and eax, edx /* eax &= hold */ |
| mov eax, [ebp+eax*4] /* eax = lcode[hold & lmask] */ |
| |
| L_dolen: |
| mov cl, ah /* cl = this.bits */ |
| sub bl, ah /* bits -= this.bits */ |
| shr edx, cl /* hold >>= this.bits */ |
| |
| test al, al |
| jnz L_test_for_length_base /* if (op != 0) 45.7% */ |
| |
| shr eax, 16 /* output this.val char */ |
| stosb |
| jmp L_while_test |
| |
| L_test_for_length_base: |
| mov ecx, eax /* len = this */ |
| shr ecx, 16 /* len = this.val */ |
| mov [esp+60], ecx /* len = this */ |
| mov cl, al |
| |
| test al, 16 |
| jz L_test_for_second_level_length /* if ((op & 16) == 0) 8% */ |
| and cl, 15 /* op &= 15 */ |
| jz L_decode_distance /* if (!op) */ |
| cmp bl, cl |
| jae L_add_bits_to_len /* if (op <= bits) */ |
| |
| mov ch, cl /* stash op in ch, freeing cl */ |
| xor eax, eax |
| lodsw /* al = *(ushort *)in++ */ |
| mov cl, bl /* cl = bits, needs it for shifting */ |
| add bl, 16 /* bits += 16 */ |
| shl eax, cl |
| or edx, eax /* hold |= *((ushort *)in)++ << bits */ |
| mov cl, ch /* move op back to ecx */ |
| |
| L_add_bits_to_len: |
| mov eax, 1 |
| shl eax, cl |
| dec eax |
| sub bl, cl |
| and eax, edx /* eax &= hold */ |
| shr edx, cl |
| add [esp+60], eax /* len += hold & mask[op] */ |
| |
| L_decode_distance: |
| cmp bl, 15 |
| ja L_get_distance_code /* if (15 < bits) */ |
| |
| xor eax, eax |
| lodsw /* al = *(ushort *)in++ */ |
| mov cl, bl /* cl = bits, needs it for shifting */ |
| add bl, 16 /* bits += 16 */ |
| shl eax, cl |
| or edx, eax /* hold |= *((ushort *)in)++ << bits */ |
| |
| L_get_distance_code: |
| mov eax, [esp+56] /* eax = dmask */ |
| mov ecx, [esp+48] /* ecx = dcode */ |
| and eax, edx /* eax &= hold */ |
| mov eax, [ecx+eax*4]/* eax = dcode[hold & dmask] */ |
| |
| L_dodist: |
| mov ebp, eax /* dist = this */ |
| shr ebp, 16 /* dist = this.val */ |
| mov cl, ah |
| sub bl, ah /* bits -= this.bits */ |
| shr edx, cl /* hold >>= this.bits */ |
| mov cl, al /* cl = this.op */ |
| |
| test al, 16 /* if ((op & 16) == 0) */ |
| jz L_test_for_second_level_dist |
| and cl, 15 /* op &= 15 */ |
| jz L_check_dist_one |
| cmp bl, cl |
| jae L_add_bits_to_dist /* if (op <= bits) 97.6% */ |
| |
| mov ch, cl /* stash op in ch, freeing cl */ |
| xor eax, eax |
| lodsw /* al = *(ushort *)in++ */ |
| mov cl, bl /* cl = bits, needs it for shifting */ |
| add bl, 16 /* bits += 16 */ |
| shl eax, cl |
| or edx, eax /* hold |= *((ushort *)in)++ << bits */ |
| mov cl, ch /* move op back to ecx */ |
| |
| L_add_bits_to_dist: |
| mov eax, 1 |
| shl eax, cl |
| dec eax /* (1 << op) - 1 */ |
| sub bl, cl |
| and eax, edx /* eax &= hold */ |
| shr edx, cl |
| add ebp, eax /* dist += hold & ((1 << op) - 1) */ |
| |
| L_check_window: |
| mov [esp+4], esi /* save in so from can use it's reg */ |
| mov eax, edi |
| sub eax, [esp+16] /* nbytes = out - beg */ |
| |
| cmp eax, ebp |
| jb L_clip_window /* if (dist > nbytes) 4.2% */ |
| |
| mov ecx, [esp+60] |
| mov esi, edi |
| sub esi, ebp /* from = out - dist */ |
| |
| sub ecx, 3 /* copy from to out */ |
| mov al, [esi] |
| mov [edi], al |
| mov al, [esi+1] |
| mov ah, [esi+2] |
| add esi, 3 |
| mov [edi+1], al |
| mov [edi+2], ah |
| add edi, 3 |
| rep movsb |
| |
| mov esi, [esp+4] /* move in back to %esi, toss from */ |
| mov ebp, [esp+44] /* ebp = lcode */ |
| jmp L_while_test |
| |
| L_check_dist_one: |
| cmp ebp, 1 /* if dist 1, is a memset */ |
| jne L_check_window |
| cmp [esp+16], edi |
| je L_check_window |
| |
| dec edi |
| mov ecx, [esp+60] |
| mov al, [edi] |
| sub ecx, 3 |
| |
| mov [edi+1], al /* memset out with from[-1] */ |
| mov [edi+2], al |
| mov [edi+3], al |
| add edi, 4 |
| rep stosb |
| mov ebp, [esp+44] /* ebp = lcode */ |
| jmp L_while_test |
| |
| L_test_for_second_level_length: |
| test al, 64 |
| jnz L_test_for_end_of_block /* if ((op & 64) != 0) */ |
| |
| mov eax, 1 |
| shl eax, cl |
| dec eax |
| and eax, edx /* eax &= hold */ |
| add eax, [esp+60] /* eax += this.val */ |
| mov eax, [ebp+eax*4] /* eax = lcode[val+(hold&mask[op])]*/ |
| jmp L_dolen |
| |
| L_test_for_second_level_dist: |
| test al, 64 |
| jnz L_invalid_distance_code /* if ((op & 64) != 0) */ |
| |
| mov eax, 1 |
| shl eax, cl |
| dec eax |
| and eax, edx /* eax &= hold */ |
| add eax, ebp /* eax += this.val */ |
| mov ecx, [esp+48] /* ecx = dcode */ |
| mov eax, [ecx+eax*4] /* eax = dcode[val+(hold&mask[op])]*/ |
| jmp L_dodist |
| |
| L_clip_window: |
| mov ecx, eax |
| mov eax, [esp+24] /* prepare for dist compare */ |
| neg ecx /* nbytes = -nbytes */ |
| mov esi, [esp+32] /* from = window */ |
| |
| cmp eax, ebp |
| jb L_invalid_distance_too_far /* if (dist > wsize) */ |
| |
| add ecx, ebp /* nbytes = dist - nbytes */ |
| cmp dword ptr [esp+28], 0 |
| jne L_wrap_around_window /* if (write != 0) */ |
| |
| sub eax, ecx |
| add esi, eax /* from += wsize - nbytes */ |
| |
| mov eax, [esp+60] |
| cmp eax, ecx |
| jbe L_do_copy1 /* if (nbytes >= len) */ |
| |
| sub eax, ecx /* len -= nbytes */ |
| rep movsb |
| mov esi, edi |
| sub esi, ebp /* from = out - dist */ |
| jmp L_do_copy1 |
| |
| cmp eax, ecx |
| jbe L_do_copy1 /* if (nbytes >= len) */ |
| |
| sub eax, ecx /* len -= nbytes */ |
| rep movsb |
| mov esi, edi |
| sub esi, ebp /* from = out - dist */ |
| jmp L_do_copy1 |
| |
| L_wrap_around_window: |
| mov eax, [esp+28] |
| cmp ecx, eax |
| jbe L_contiguous_in_window /* if (write >= nbytes) */ |
| |
| add esi, [esp+24] |
| add esi, eax |
| sub esi, ecx /* from += wsize + write - nbytes */ |
| sub ecx, eax /* nbytes -= write */ |
| |
| mov eax, [esp+60] |
| cmp eax, ecx |
| jbe L_do_copy1 /* if (nbytes >= len) */ |
| |
| sub eax, ecx /* len -= nbytes */ |
| rep movsb |
| mov esi, [esp+32] /* from = window */ |
| mov ecx, [esp+28] /* nbytes = write */ |
| cmp eax, ecx |
| jbe L_do_copy1 /* if (nbytes >= len) */ |
| |
| sub eax, ecx /* len -= nbytes */ |
| rep movsb |
| mov esi, edi |
| sub esi, ebp /* from = out - dist */ |
| jmp L_do_copy1 |
| |
| L_contiguous_in_window: |
| add esi, eax |
| sub esi, ecx /* from += write - nbytes */ |
| |
| mov eax, [esp+60] |
| cmp eax, ecx |
| jbe L_do_copy1 /* if (nbytes >= len) */ |
| |
| sub eax, ecx /* len -= nbytes */ |
| rep movsb |
| mov esi, edi |
| sub esi, ebp /* from = out - dist */ |
| |
| L_do_copy1: |
| mov ecx, eax |
| rep movsb |
| |
| mov esi, [esp+4] /* move in back to %esi, toss from */ |
| mov ebp, [esp+44] /* ebp = lcode */ |
| jmp L_while_test |
| |
| L_test_for_end_of_block: |
| test al, 32 |
| jz L_invalid_literal_length_code |
| mov dword ptr [esp+68], 1 |
| jmp L_break_loop_with_status |
| |
| L_invalid_literal_length_code: |
| mov dword ptr [esp+68], 2 |
| jmp L_break_loop_with_status |
| |
| L_invalid_distance_code: |
| mov dword ptr [esp+68], 3 |
| jmp L_break_loop_with_status |
| |
| L_invalid_distance_too_far: |
| mov esi, [esp+4] |
| mov dword ptr [esp+68], 4 |
| jmp L_break_loop_with_status |
| |
| L_break_loop: |
| mov dword ptr [esp+68], 0 |
| |
| L_break_loop_with_status: |
| /* put in, out, bits, and hold back into ar and pop esp */ |
| mov [esp+4], esi |
| mov [esp+12], edi |
| mov [esp+40], ebx |
| mov [esp+36], edx |
| mov esp, [esp] |
| pop ebp |
| popfd |
| } |
| #endif |
| |
| if (ar.status > 1) { |
| if (ar.status == 2) |
| strm->msg = "invalid literal/length code"; |
| else if (ar.status == 3) |
| strm->msg = "invalid distance code"; |
| else |
| strm->msg = "invalid distance too far back"; |
| state->mode = BAD; |
| } |
| else if ( ar.status == 1 ) { |
| state->mode = TYPE; |
| } |
| |
| /* return unused bytes (on entry, bits < 8, so in won't go too far back) */ |
| ar.len = ar.bits >> 3; |
| ar.in -= ar.len; |
| ar.bits -= ar.len << 3; |
| ar.hold &= (1U << ar.bits) - 1; |
| |
| /* update state and return */ |
| strm->next_in = ar.in; |
| strm->next_out = ar.out; |
| strm->avail_in = (unsigned)(ar.in < ar.last ? 5 + (ar.last - ar.in) : |
| 5 - (ar.in - ar.last)); |
| strm->avail_out = (unsigned)(ar.out < ar.end ? 257 + (ar.end - ar.out) : |
| 257 - (ar.out - ar.end)); |
| state->hold = ar.hold; |
| state->bits = ar.bits; |
| return; |
| } |
| |
