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-rw-r--r--compat/zlib/contrib/masmx86/match686.asm956
1 files changed, 478 insertions, 478 deletions
diff --git a/compat/zlib/contrib/masmx86/match686.asm b/compat/zlib/contrib/masmx86/match686.asm
index 21ae704..1eaf555 100644
--- a/compat/zlib/contrib/masmx86/match686.asm
+++ b/compat/zlib/contrib/masmx86/match686.asm
@@ -1,478 +1,478 @@
-; match686.asm -- Asm portion of the optimized longest_match for 32 bits x86
-; Copyright (C) 1995-1996 Jean-loup Gailly, Brian Raiter and Gilles Vollant.
-; File written by Gilles Vollant, by converting match686.S from Brian Raiter
-; for MASM. This is as assembly version of longest_match
-; from Jean-loup Gailly in deflate.c
-;
-; http://www.zlib.net
-; http://www.winimage.com/zLibDll
-; http://www.muppetlabs.com/~breadbox/software/assembly.html
-;
-; For Visual C++ 4.x and higher and ML 6.x and higher
-; ml.exe is distributed in
-; http://www.microsoft.com/downloads/details.aspx?FamilyID=7a1c9da0-0510-44a2-b042-7ef370530c64
-;
-; this file contain two implementation of longest_match
-;
-; this longest_match was written by Brian raiter (1998), optimized for Pentium Pro
-; (and the faster known version of match_init on modern Core 2 Duo and AMD Phenom)
-;
-; for using an assembly version of longest_match, you need define ASMV in project
-;
-; compile the asm file running
-; ml /coff /Zi /c /Flmatch686.lst match686.asm
-; and do not include match686.obj in your project
-;
-; note: contrib of zLib 1.2.3 and earlier contained both a deprecated version for
-; Pentium (prior Pentium Pro) and this version for Pentium Pro and modern processor
-; with autoselect (with cpu detection code)
-; if you want support the old pentium optimization, you can still use these version
-;
-; this file is not optimized for old pentium, but it compatible with all x86 32 bits
-; processor (starting 80386)
-;
-;
-; see below : zlib1222add must be adjuster if you use a zlib version < 1.2.2.2
-
-;uInt longest_match(s, cur_match)
-; deflate_state *s;
-; IPos cur_match; /* current match */
-
- NbStack equ 76
- cur_match equ dword ptr[esp+NbStack-0]
- str_s equ dword ptr[esp+NbStack-4]
-; 5 dword on top (ret,ebp,esi,edi,ebx)
- adrret equ dword ptr[esp+NbStack-8]
- pushebp equ dword ptr[esp+NbStack-12]
- pushedi equ dword ptr[esp+NbStack-16]
- pushesi equ dword ptr[esp+NbStack-20]
- pushebx equ dword ptr[esp+NbStack-24]
-
- chain_length equ dword ptr [esp+NbStack-28]
- limit equ dword ptr [esp+NbStack-32]
- best_len equ dword ptr [esp+NbStack-36]
- window equ dword ptr [esp+NbStack-40]
- prev equ dword ptr [esp+NbStack-44]
- scan_start equ word ptr [esp+NbStack-48]
- wmask equ dword ptr [esp+NbStack-52]
- match_start_ptr equ dword ptr [esp+NbStack-56]
- nice_match equ dword ptr [esp+NbStack-60]
- scan equ dword ptr [esp+NbStack-64]
-
- windowlen equ dword ptr [esp+NbStack-68]
- match_start equ dword ptr [esp+NbStack-72]
- strend equ dword ptr [esp+NbStack-76]
- NbStackAdd equ (NbStack-24)
-
- .386p
-
- name gvmatch
- .MODEL FLAT
-
-
-
-; all the +zlib1222add offsets are due to the addition of fields
-; in zlib in the deflate_state structure since the asm code was first written
-; (if you compile with zlib 1.0.4 or older, use "zlib1222add equ (-4)").
-; (if you compile with zlib between 1.0.5 and 1.2.2.1, use "zlib1222add equ 0").
-; if you compile with zlib 1.2.2.2 or later , use "zlib1222add equ 8").
-
- zlib1222add equ 8
-
-; Note : these value are good with a 8 bytes boundary pack structure
- dep_chain_length equ 74h+zlib1222add
- dep_window equ 30h+zlib1222add
- dep_strstart equ 64h+zlib1222add
- dep_prev_length equ 70h+zlib1222add
- dep_nice_match equ 88h+zlib1222add
- dep_w_size equ 24h+zlib1222add
- dep_prev equ 38h+zlib1222add
- dep_w_mask equ 2ch+zlib1222add
- dep_good_match equ 84h+zlib1222add
- dep_match_start equ 68h+zlib1222add
- dep_lookahead equ 6ch+zlib1222add
-
-
-_TEXT segment
-
-IFDEF NOUNDERLINE
- public longest_match
- public match_init
-ELSE
- public _longest_match
- public _match_init
-ENDIF
-
- MAX_MATCH equ 258
- MIN_MATCH equ 3
- MIN_LOOKAHEAD equ (MAX_MATCH+MIN_MATCH+1)
-
-
-
-MAX_MATCH equ 258
-MIN_MATCH equ 3
-MIN_LOOKAHEAD equ (MAX_MATCH + MIN_MATCH + 1)
-MAX_MATCH_8_ equ ((MAX_MATCH + 7) AND 0FFF0h)
-
-
-;;; stack frame offsets
-
-chainlenwmask equ esp + 0 ; high word: current chain len
- ; low word: s->wmask
-window equ esp + 4 ; local copy of s->window
-windowbestlen equ esp + 8 ; s->window + bestlen
-scanstart equ esp + 16 ; first two bytes of string
-scanend equ esp + 12 ; last two bytes of string
-scanalign equ esp + 20 ; dword-misalignment of string
-nicematch equ esp + 24 ; a good enough match size
-bestlen equ esp + 28 ; size of best match so far
-scan equ esp + 32 ; ptr to string wanting match
-
-LocalVarsSize equ 36
-; saved ebx byte esp + 36
-; saved edi byte esp + 40
-; saved esi byte esp + 44
-; saved ebp byte esp + 48
-; return address byte esp + 52
-deflatestate equ esp + 56 ; the function arguments
-curmatch equ esp + 60
-
-;;; Offsets for fields in the deflate_state structure. These numbers
-;;; are calculated from the definition of deflate_state, with the
-;;; assumption that the compiler will dword-align the fields. (Thus,
-;;; changing the definition of deflate_state could easily cause this
-;;; program to crash horribly, without so much as a warning at
-;;; compile time. Sigh.)
-
-dsWSize equ 36+zlib1222add
-dsWMask equ 44+zlib1222add
-dsWindow equ 48+zlib1222add
-dsPrev equ 56+zlib1222add
-dsMatchLen equ 88+zlib1222add
-dsPrevMatch equ 92+zlib1222add
-dsStrStart equ 100+zlib1222add
-dsMatchStart equ 104+zlib1222add
-dsLookahead equ 108+zlib1222add
-dsPrevLen equ 112+zlib1222add
-dsMaxChainLen equ 116+zlib1222add
-dsGoodMatch equ 132+zlib1222add
-dsNiceMatch equ 136+zlib1222add
-
-
-;;; match686.asm -- Pentium-Pro-optimized version of longest_match()
-;;; Written for zlib 1.1.2
-;;; Copyright (C) 1998 Brian Raiter <breadbox@muppetlabs.com>
-;;; You can look at http://www.muppetlabs.com/~breadbox/software/assembly.html
-;;;
-;;
-;; This software is provided 'as-is', without any express or implied
-;; warranty. In no event will the authors be held liable for any damages
-;; arising from the use of this software.
-;;
-;; Permission is granted to anyone to use this software for any purpose,
-;; including commercial applications, and to alter it and redistribute it
-;; freely, subject to the following restrictions:
-;;
-;; 1. The origin of this software must not be misrepresented; you must not
-;; claim that you wrote the original software. If you use this software
-;; in a product, an acknowledgment in the product documentation would be
-;; appreciated but is not required.
-;; 2. Altered source versions must be plainly marked as such, and must not be
-;; misrepresented as being the original software
-;; 3. This notice may not be removed or altered from any source distribution.
-;;
-
-;GLOBAL _longest_match, _match_init
-
-
-;SECTION .text
-
-;;; uInt longest_match(deflate_state *deflatestate, IPos curmatch)
-
-;_longest_match:
- IFDEF NOUNDERLINE
- longest_match proc near
- ELSE
- _longest_match proc near
- ENDIF
-
-;;; Save registers that the compiler may be using, and adjust esp to
-;;; make room for our stack frame.
-
- push ebp
- push edi
- push esi
- push ebx
- sub esp, LocalVarsSize
-
-;;; Retrieve the function arguments. ecx will hold cur_match
-;;; throughout the entire function. edx will hold the pointer to the
-;;; deflate_state structure during the function's setup (before
-;;; entering the main loop.
-
- mov edx, [deflatestate]
- mov ecx, [curmatch]
-
-;;; uInt wmask = s->w_mask;
-;;; unsigned chain_length = s->max_chain_length;
-;;; if (s->prev_length >= s->good_match) {
-;;; chain_length >>= 2;
-;;; }
-
- mov eax, [edx + dsPrevLen]
- mov ebx, [edx + dsGoodMatch]
- cmp eax, ebx
- mov eax, [edx + dsWMask]
- mov ebx, [edx + dsMaxChainLen]
- jl LastMatchGood
- shr ebx, 2
-LastMatchGood:
-
-;;; chainlen is decremented once beforehand so that the function can
-;;; use the sign flag instead of the zero flag for the exit test.
-;;; It is then shifted into the high word, to make room for the wmask
-;;; value, which it will always accompany.
-
- dec ebx
- shl ebx, 16
- or ebx, eax
- mov [chainlenwmask], ebx
-
-;;; if ((uInt)nice_match > s->lookahead) nice_match = s->lookahead;
-
- mov eax, [edx + dsNiceMatch]
- mov ebx, [edx + dsLookahead]
- cmp ebx, eax
- jl LookaheadLess
- mov ebx, eax
-LookaheadLess: mov [nicematch], ebx
-
-;;; register Bytef *scan = s->window + s->strstart;
-
- mov esi, [edx + dsWindow]
- mov [window], esi
- mov ebp, [edx + dsStrStart]
- lea edi, [esi + ebp]
- mov [scan], edi
-
-;;; Determine how many bytes the scan ptr is off from being
-;;; dword-aligned.
-
- mov eax, edi
- neg eax
- and eax, 3
- mov [scanalign], eax
-
-;;; IPos limit = s->strstart > (IPos)MAX_DIST(s) ?
-;;; s->strstart - (IPos)MAX_DIST(s) : NIL;
-
- mov eax, [edx + dsWSize]
- sub eax, MIN_LOOKAHEAD
- sub ebp, eax
- jg LimitPositive
- xor ebp, ebp
-LimitPositive:
-
-;;; int best_len = s->prev_length;
-
- mov eax, [edx + dsPrevLen]
- mov [bestlen], eax
-
-;;; Store the sum of s->window + best_len in esi locally, and in esi.
-
- add esi, eax
- mov [windowbestlen], esi
-
-;;; register ush scan_start = *(ushf*)scan;
-;;; register ush scan_end = *(ushf*)(scan+best_len-1);
-;;; Posf *prev = s->prev;
-
- movzx ebx, word ptr [edi]
- mov [scanstart], ebx
- movzx ebx, word ptr [edi + eax - 1]
- mov [scanend], ebx
- mov edi, [edx + dsPrev]
-
-;;; Jump into the main loop.
-
- mov edx, [chainlenwmask]
- jmp short LoopEntry
-
-align 4
-
-;;; do {
-;;; match = s->window + cur_match;
-;;; if (*(ushf*)(match+best_len-1) != scan_end ||
-;;; *(ushf*)match != scan_start) continue;
-;;; [...]
-;;; } while ((cur_match = prev[cur_match & wmask]) > limit
-;;; && --chain_length != 0);
-;;;
-;;; Here is the inner loop of the function. The function will spend the
-;;; majority of its time in this loop, and majority of that time will
-;;; be spent in the first ten instructions.
-;;;
-;;; Within this loop:
-;;; ebx = scanend
-;;; ecx = curmatch
-;;; edx = chainlenwmask - i.e., ((chainlen << 16) | wmask)
-;;; esi = windowbestlen - i.e., (window + bestlen)
-;;; edi = prev
-;;; ebp = limit
-
-LookupLoop:
- and ecx, edx
- movzx ecx, word ptr [edi + ecx*2]
- cmp ecx, ebp
- jbe LeaveNow
- sub edx, 00010000h
- js LeaveNow
-LoopEntry: movzx eax, word ptr [esi + ecx - 1]
- cmp eax, ebx
- jnz LookupLoop
- mov eax, [window]
- movzx eax, word ptr [eax + ecx]
- cmp eax, [scanstart]
- jnz LookupLoop
-
-;;; Store the current value of chainlen.
-
- mov [chainlenwmask], edx
-
-;;; Point edi to the string under scrutiny, and esi to the string we
-;;; are hoping to match it up with. In actuality, esi and edi are
-;;; both pointed (MAX_MATCH_8 - scanalign) bytes ahead, and edx is
-;;; initialized to -(MAX_MATCH_8 - scanalign).
-
- mov esi, [window]
- mov edi, [scan]
- add esi, ecx
- mov eax, [scanalign]
- mov edx, 0fffffef8h; -(MAX_MATCH_8)
- lea edi, [edi + eax + 0108h] ;MAX_MATCH_8]
- lea esi, [esi + eax + 0108h] ;MAX_MATCH_8]
-
-;;; Test the strings for equality, 8 bytes at a time. At the end,
-;;; adjust edx so that it is offset to the exact byte that mismatched.
-;;;
-;;; We already know at this point that the first three bytes of the
-;;; strings match each other, and they can be safely passed over before
-;;; starting the compare loop. So what this code does is skip over 0-3
-;;; bytes, as much as necessary in order to dword-align the edi
-;;; pointer. (esi will still be misaligned three times out of four.)
-;;;
-;;; It should be confessed that this loop usually does not represent
-;;; much of the total running time. Replacing it with a more
-;;; straightforward "rep cmpsb" would not drastically degrade
-;;; performance.
-
-LoopCmps:
- mov eax, [esi + edx]
- xor eax, [edi + edx]
- jnz LeaveLoopCmps
- mov eax, [esi + edx + 4]
- xor eax, [edi + edx + 4]
- jnz LeaveLoopCmps4
- add edx, 8
- jnz LoopCmps
- jmp short LenMaximum
-LeaveLoopCmps4: add edx, 4
-LeaveLoopCmps: test eax, 0000FFFFh
- jnz LenLower
- add edx, 2
- shr eax, 16
-LenLower: sub al, 1
- adc edx, 0
-
-;;; Calculate the length of the match. If it is longer than MAX_MATCH,
-;;; then automatically accept it as the best possible match and leave.
-
- lea eax, [edi + edx]
- mov edi, [scan]
- sub eax, edi
- cmp eax, MAX_MATCH
- jge LenMaximum
-
-;;; If the length of the match is not longer than the best match we
-;;; have so far, then forget it and return to the lookup loop.
-
- mov edx, [deflatestate]
- mov ebx, [bestlen]
- cmp eax, ebx
- jg LongerMatch
- mov esi, [windowbestlen]
- mov edi, [edx + dsPrev]
- mov ebx, [scanend]
- mov edx, [chainlenwmask]
- jmp LookupLoop
-
-;;; s->match_start = cur_match;
-;;; best_len = len;
-;;; if (len >= nice_match) break;
-;;; scan_end = *(ushf*)(scan+best_len-1);
-
-LongerMatch: mov ebx, [nicematch]
- mov [bestlen], eax
- mov [edx + dsMatchStart], ecx
- cmp eax, ebx
- jge LeaveNow
- mov esi, [window]
- add esi, eax
- mov [windowbestlen], esi
- movzx ebx, word ptr [edi + eax - 1]
- mov edi, [edx + dsPrev]
- mov [scanend], ebx
- mov edx, [chainlenwmask]
- jmp LookupLoop
-
-;;; Accept the current string, with the maximum possible length.
-
-LenMaximum: mov edx, [deflatestate]
- mov dword ptr [bestlen], MAX_MATCH
- mov [edx + dsMatchStart], ecx
-
-;;; if ((uInt)best_len <= s->lookahead) return (uInt)best_len;
-;;; return s->lookahead;
-
-LeaveNow:
- mov edx, [deflatestate]
- mov ebx, [bestlen]
- mov eax, [edx + dsLookahead]
- cmp ebx, eax
- jg LookaheadRet
- mov eax, ebx
-LookaheadRet:
-
-;;; Restore the stack and return from whence we came.
-
- add esp, LocalVarsSize
- pop ebx
- pop esi
- pop edi
- pop ebp
-
- ret
-; please don't remove this string !
-; Your can freely use match686 in any free or commercial app if you don't remove the string in the binary!
- db 0dh,0ah,"asm686 with masm, optimised assembly code from Brian Raiter, written 1998",0dh,0ah
-
-
- IFDEF NOUNDERLINE
- longest_match endp
- ELSE
- _longest_match endp
- ENDIF
-
- IFDEF NOUNDERLINE
- match_init proc near
- ret
- match_init endp
- ELSE
- _match_init proc near
- ret
- _match_init endp
- ENDIF
-
-
-_TEXT ends
-end
+; match686.asm -- Asm portion of the optimized longest_match for 32 bits x86
+; Copyright (C) 1995-1996 Jean-loup Gailly, Brian Raiter and Gilles Vollant.
+; File written by Gilles Vollant, by converting match686.S from Brian Raiter
+; for MASM. This is as assembly version of longest_match
+; from Jean-loup Gailly in deflate.c
+;
+; http://www.zlib.net
+; http://www.winimage.com/zLibDll
+; http://www.muppetlabs.com/~breadbox/software/assembly.html
+;
+; For Visual C++ 4.x and higher and ML 6.x and higher
+; ml.exe is distributed in
+; http://www.microsoft.com/downloads/details.aspx?FamilyID=7a1c9da0-0510-44a2-b042-7ef370530c64
+;
+; this file contain two implementation of longest_match
+;
+; this longest_match was written by Brian raiter (1998), optimized for Pentium Pro
+; (and the faster known version of match_init on modern Core 2 Duo and AMD Phenom)
+;
+; for using an assembly version of longest_match, you need define ASMV in project
+;
+; compile the asm file running
+; ml /coff /Zi /c /Flmatch686.lst match686.asm
+; and do not include match686.obj in your project
+;
+; note: contrib of zLib 1.2.3 and earlier contained both a deprecated version for
+; Pentium (prior Pentium Pro) and this version for Pentium Pro and modern processor
+; with autoselect (with cpu detection code)
+; if you want support the old pentium optimization, you can still use these version
+;
+; this file is not optimized for old pentium, but it compatible with all x86 32 bits
+; processor (starting 80386)
+;
+;
+; see below : zlib1222add must be adjuster if you use a zlib version < 1.2.2.2
+
+;uInt longest_match(s, cur_match)
+; deflate_state *s;
+; IPos cur_match; /* current match */
+
+ NbStack equ 76
+ cur_match equ dword ptr[esp+NbStack-0]
+ str_s equ dword ptr[esp+NbStack-4]
+; 5 dword on top (ret,ebp,esi,edi,ebx)
+ adrret equ dword ptr[esp+NbStack-8]
+ pushebp equ dword ptr[esp+NbStack-12]
+ pushedi equ dword ptr[esp+NbStack-16]
+ pushesi equ dword ptr[esp+NbStack-20]
+ pushebx equ dword ptr[esp+NbStack-24]
+
+ chain_length equ dword ptr [esp+NbStack-28]
+ limit equ dword ptr [esp+NbStack-32]
+ best_len equ dword ptr [esp+NbStack-36]
+ window equ dword ptr [esp+NbStack-40]
+ prev equ dword ptr [esp+NbStack-44]
+ scan_start equ word ptr [esp+NbStack-48]
+ wmask equ dword ptr [esp+NbStack-52]
+ match_start_ptr equ dword ptr [esp+NbStack-56]
+ nice_match equ dword ptr [esp+NbStack-60]
+ scan equ dword ptr [esp+NbStack-64]
+
+ windowlen equ dword ptr [esp+NbStack-68]
+ match_start equ dword ptr [esp+NbStack-72]
+ strend equ dword ptr [esp+NbStack-76]
+ NbStackAdd equ (NbStack-24)
+
+ .386p
+
+ name gvmatch
+ .MODEL FLAT
+
+
+
+; all the +zlib1222add offsets are due to the addition of fields
+; in zlib in the deflate_state structure since the asm code was first written
+; (if you compile with zlib 1.0.4 or older, use "zlib1222add equ (-4)").
+; (if you compile with zlib between 1.0.5 and 1.2.2.1, use "zlib1222add equ 0").
+; if you compile with zlib 1.2.2.2 or later , use "zlib1222add equ 8").
+
+ zlib1222add equ 8
+
+; Note : these value are good with a 8 bytes boundary pack structure
+ dep_chain_length equ 74h+zlib1222add
+ dep_window equ 30h+zlib1222add
+ dep_strstart equ 64h+zlib1222add
+ dep_prev_length equ 70h+zlib1222add
+ dep_nice_match equ 88h+zlib1222add
+ dep_w_size equ 24h+zlib1222add
+ dep_prev equ 38h+zlib1222add
+ dep_w_mask equ 2ch+zlib1222add
+ dep_good_match equ 84h+zlib1222add
+ dep_match_start equ 68h+zlib1222add
+ dep_lookahead equ 6ch+zlib1222add
+
+
+_TEXT segment
+
+IFDEF NOUNDERLINE
+ public longest_match
+ public match_init
+ELSE
+ public _longest_match
+ public _match_init
+ENDIF
+
+ MAX_MATCH equ 258
+ MIN_MATCH equ 3
+ MIN_LOOKAHEAD equ (MAX_MATCH+MIN_MATCH+1)
+
+
+
+MAX_MATCH equ 258
+MIN_MATCH equ 3
+MIN_LOOKAHEAD equ (MAX_MATCH + MIN_MATCH + 1)
+MAX_MATCH_8_ equ ((MAX_MATCH + 7) AND 0FFF0h)
+
+
+;;; stack frame offsets
+
+chainlenwmask equ esp + 0 ; high word: current chain len
+ ; low word: s->wmask
+window equ esp + 4 ; local copy of s->window
+windowbestlen equ esp + 8 ; s->window + bestlen
+scanstart equ esp + 16 ; first two bytes of string
+scanend equ esp + 12 ; last two bytes of string
+scanalign equ esp + 20 ; dword-misalignment of string
+nicematch equ esp + 24 ; a good enough match size
+bestlen equ esp + 28 ; size of best match so far
+scan equ esp + 32 ; ptr to string wanting match
+
+LocalVarsSize equ 36
+; saved ebx byte esp + 36
+; saved edi byte esp + 40
+; saved esi byte esp + 44
+; saved ebp byte esp + 48
+; return address byte esp + 52
+deflatestate equ esp + 56 ; the function arguments
+curmatch equ esp + 60
+
+;;; Offsets for fields in the deflate_state structure. These numbers
+;;; are calculated from the definition of deflate_state, with the
+;;; assumption that the compiler will dword-align the fields. (Thus,
+;;; changing the definition of deflate_state could easily cause this
+;;; program to crash horribly, without so much as a warning at
+;;; compile time. Sigh.)
+
+dsWSize equ 36+zlib1222add
+dsWMask equ 44+zlib1222add
+dsWindow equ 48+zlib1222add
+dsPrev equ 56+zlib1222add
+dsMatchLen equ 88+zlib1222add
+dsPrevMatch equ 92+zlib1222add
+dsStrStart equ 100+zlib1222add
+dsMatchStart equ 104+zlib1222add
+dsLookahead equ 108+zlib1222add
+dsPrevLen equ 112+zlib1222add
+dsMaxChainLen equ 116+zlib1222add
+dsGoodMatch equ 132+zlib1222add
+dsNiceMatch equ 136+zlib1222add
+
+
+;;; match686.asm -- Pentium-Pro-optimized version of longest_match()
+;;; Written for zlib 1.1.2
+;;; Copyright (C) 1998 Brian Raiter <breadbox@muppetlabs.com>
+;;; You can look at http://www.muppetlabs.com/~breadbox/software/assembly.html
+;;;
+;;
+;; This software is provided 'as-is', without any express or implied
+;; warranty. In no event will the authors be held liable for any damages
+;; arising from the use of this software.
+;;
+;; Permission is granted to anyone to use this software for any purpose,
+;; including commercial applications, and to alter it and redistribute it
+;; freely, subject to the following restrictions:
+;;
+;; 1. The origin of this software must not be misrepresented; you must not
+;; claim that you wrote the original software. If you use this software
+;; in a product, an acknowledgment in the product documentation would be
+;; appreciated but is not required.
+;; 2. Altered source versions must be plainly marked as such, and must not be
+;; misrepresented as being the original software
+;; 3. This notice may not be removed or altered from any source distribution.
+;;
+
+;GLOBAL _longest_match, _match_init
+
+
+;SECTION .text
+
+;;; uInt longest_match(deflate_state *deflatestate, IPos curmatch)
+
+;_longest_match:
+ IFDEF NOUNDERLINE
+ longest_match proc near
+ ELSE
+ _longest_match proc near
+ ENDIF
+
+;;; Save registers that the compiler may be using, and adjust esp to
+;;; make room for our stack frame.
+
+ push ebp
+ push edi
+ push esi
+ push ebx
+ sub esp, LocalVarsSize
+
+;;; Retrieve the function arguments. ecx will hold cur_match
+;;; throughout the entire function. edx will hold the pointer to the
+;;; deflate_state structure during the function's setup (before
+;;; entering the main loop.
+
+ mov edx, [deflatestate]
+ mov ecx, [curmatch]
+
+;;; uInt wmask = s->w_mask;
+;;; unsigned chain_length = s->max_chain_length;
+;;; if (s->prev_length >= s->good_match) {
+;;; chain_length >>= 2;
+;;; }
+
+ mov eax, [edx + dsPrevLen]
+ mov ebx, [edx + dsGoodMatch]
+ cmp eax, ebx
+ mov eax, [edx + dsWMask]
+ mov ebx, [edx + dsMaxChainLen]
+ jl LastMatchGood
+ shr ebx, 2
+LastMatchGood:
+
+;;; chainlen is decremented once beforehand so that the function can
+;;; use the sign flag instead of the zero flag for the exit test.
+;;; It is then shifted into the high word, to make room for the wmask
+;;; value, which it will always accompany.
+
+ dec ebx
+ shl ebx, 16
+ or ebx, eax
+ mov [chainlenwmask], ebx
+
+;;; if ((uInt)nice_match > s->lookahead) nice_match = s->lookahead;
+
+ mov eax, [edx + dsNiceMatch]
+ mov ebx, [edx + dsLookahead]
+ cmp ebx, eax
+ jl LookaheadLess
+ mov ebx, eax
+LookaheadLess: mov [nicematch], ebx
+
+;;; register Bytef *scan = s->window + s->strstart;
+
+ mov esi, [edx + dsWindow]
+ mov [window], esi
+ mov ebp, [edx + dsStrStart]
+ lea edi, [esi + ebp]
+ mov [scan], edi
+
+;;; Determine how many bytes the scan ptr is off from being
+;;; dword-aligned.
+
+ mov eax, edi
+ neg eax
+ and eax, 3
+ mov [scanalign], eax
+
+;;; IPos limit = s->strstart > (IPos)MAX_DIST(s) ?
+;;; s->strstart - (IPos)MAX_DIST(s) : NIL;
+
+ mov eax, [edx + dsWSize]
+ sub eax, MIN_LOOKAHEAD
+ sub ebp, eax
+ jg LimitPositive
+ xor ebp, ebp
+LimitPositive:
+
+;;; int best_len = s->prev_length;
+
+ mov eax, [edx + dsPrevLen]
+ mov [bestlen], eax
+
+;;; Store the sum of s->window + best_len in esi locally, and in esi.
+
+ add esi, eax
+ mov [windowbestlen], esi
+
+;;; register ush scan_start = *(ushf*)scan;
+;;; register ush scan_end = *(ushf*)(scan+best_len-1);
+;;; Posf *prev = s->prev;
+
+ movzx ebx, word ptr [edi]
+ mov [scanstart], ebx
+ movzx ebx, word ptr [edi + eax - 1]
+ mov [scanend], ebx
+ mov edi, [edx + dsPrev]
+
+;;; Jump into the main loop.
+
+ mov edx, [chainlenwmask]
+ jmp short LoopEntry
+
+align 4
+
+;;; do {
+;;; match = s->window + cur_match;
+;;; if (*(ushf*)(match+best_len-1) != scan_end ||
+;;; *(ushf*)match != scan_start) continue;
+;;; [...]
+;;; } while ((cur_match = prev[cur_match & wmask]) > limit
+;;; && --chain_length != 0);
+;;;
+;;; Here is the inner loop of the function. The function will spend the
+;;; majority of its time in this loop, and majority of that time will
+;;; be spent in the first ten instructions.
+;;;
+;;; Within this loop:
+;;; ebx = scanend
+;;; ecx = curmatch
+;;; edx = chainlenwmask - i.e., ((chainlen << 16) | wmask)
+;;; esi = windowbestlen - i.e., (window + bestlen)
+;;; edi = prev
+;;; ebp = limit
+
+LookupLoop:
+ and ecx, edx
+ movzx ecx, word ptr [edi + ecx*2]
+ cmp ecx, ebp
+ jbe LeaveNow
+ sub edx, 00010000h
+ js LeaveNow
+LoopEntry: movzx eax, word ptr [esi + ecx - 1]
+ cmp eax, ebx
+ jnz LookupLoop
+ mov eax, [window]
+ movzx eax, word ptr [eax + ecx]
+ cmp eax, [scanstart]
+ jnz LookupLoop
+
+;;; Store the current value of chainlen.
+
+ mov [chainlenwmask], edx
+
+;;; Point edi to the string under scrutiny, and esi to the string we
+;;; are hoping to match it up with. In actuality, esi and edi are
+;;; both pointed (MAX_MATCH_8 - scanalign) bytes ahead, and edx is
+;;; initialized to -(MAX_MATCH_8 - scanalign).
+
+ mov esi, [window]
+ mov edi, [scan]
+ add esi, ecx
+ mov eax, [scanalign]
+ mov edx, 0fffffef8h; -(MAX_MATCH_8)
+ lea edi, [edi + eax + 0108h] ;MAX_MATCH_8]
+ lea esi, [esi + eax + 0108h] ;MAX_MATCH_8]
+
+;;; Test the strings for equality, 8 bytes at a time. At the end,
+;;; adjust edx so that it is offset to the exact byte that mismatched.
+;;;
+;;; We already know at this point that the first three bytes of the
+;;; strings match each other, and they can be safely passed over before
+;;; starting the compare loop. So what this code does is skip over 0-3
+;;; bytes, as much as necessary in order to dword-align the edi
+;;; pointer. (esi will still be misaligned three times out of four.)
+;;;
+;;; It should be confessed that this loop usually does not represent
+;;; much of the total running time. Replacing it with a more
+;;; straightforward "rep cmpsb" would not drastically degrade
+;;; performance.
+
+LoopCmps:
+ mov eax, [esi + edx]
+ xor eax, [edi + edx]
+ jnz LeaveLoopCmps
+ mov eax, [esi + edx + 4]
+ xor eax, [edi + edx + 4]
+ jnz LeaveLoopCmps4
+ add edx, 8
+ jnz LoopCmps
+ jmp short LenMaximum
+LeaveLoopCmps4: add edx, 4
+LeaveLoopCmps: test eax, 0000FFFFh
+ jnz LenLower
+ add edx, 2
+ shr eax, 16
+LenLower: sub al, 1
+ adc edx, 0
+
+;;; Calculate the length of the match. If it is longer than MAX_MATCH,
+;;; then automatically accept it as the best possible match and leave.
+
+ lea eax, [edi + edx]
+ mov edi, [scan]
+ sub eax, edi
+ cmp eax, MAX_MATCH
+ jge LenMaximum
+
+;;; If the length of the match is not longer than the best match we
+;;; have so far, then forget it and return to the lookup loop.
+
+ mov edx, [deflatestate]
+ mov ebx, [bestlen]
+ cmp eax, ebx
+ jg LongerMatch
+ mov esi, [windowbestlen]
+ mov edi, [edx + dsPrev]
+ mov ebx, [scanend]
+ mov edx, [chainlenwmask]
+ jmp LookupLoop
+
+;;; s->match_start = cur_match;
+;;; best_len = len;
+;;; if (len >= nice_match) break;
+;;; scan_end = *(ushf*)(scan+best_len-1);
+
+LongerMatch: mov ebx, [nicematch]
+ mov [bestlen], eax
+ mov [edx + dsMatchStart], ecx
+ cmp eax, ebx
+ jge LeaveNow
+ mov esi, [window]
+ add esi, eax
+ mov [windowbestlen], esi
+ movzx ebx, word ptr [edi + eax - 1]
+ mov edi, [edx + dsPrev]
+ mov [scanend], ebx
+ mov edx, [chainlenwmask]
+ jmp LookupLoop
+
+;;; Accept the current string, with the maximum possible length.
+
+LenMaximum: mov edx, [deflatestate]
+ mov dword ptr [bestlen], MAX_MATCH
+ mov [edx + dsMatchStart], ecx
+
+;;; if ((uInt)best_len <= s->lookahead) return (uInt)best_len;
+;;; return s->lookahead;
+
+LeaveNow:
+ mov edx, [deflatestate]
+ mov ebx, [bestlen]
+ mov eax, [edx + dsLookahead]
+ cmp ebx, eax
+ jg LookaheadRet
+ mov eax, ebx
+LookaheadRet:
+
+;;; Restore the stack and return from whence we came.
+
+ add esp, LocalVarsSize
+ pop ebx
+ pop esi
+ pop edi
+ pop ebp
+
+ ret
+; please don't remove this string !
+; Your can freely use match686 in any free or commercial app if you don't remove the string in the binary!
+ db 0dh,0ah,"asm686 with masm, optimised assembly code from Brian Raiter, written 1998",0dh,0ah
+
+
+ IFDEF NOUNDERLINE
+ longest_match endp
+ ELSE
+ _longest_match endp
+ ENDIF
+
+ IFDEF NOUNDERLINE
+ match_init proc near
+ ret
+ match_init endp
+ ELSE
+ _match_init proc near
+ ret
+ _match_init endp
+ ENDIF
+
+
+_TEXT ends
+end
generated by cgit v0.12 at 2024-11-18 17:36:46 (GMT)