554 lines
		
	
	
		
			16 KiB
		
	
	
	
		
			NASM
		
	
	
	
	
	
			
		
		
	
	
			554 lines
		
	
	
		
			16 KiB
		
	
	
	
		
			NASM
		
	
	
	
	
	
;uInt longest_match_x64(
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;    deflate_state *s,
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;    IPos cur_match);                             /* current match */
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; gvmat64.asm -- Asm portion of the optimized longest_match for 32 bits x86_64
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;  (AMD64 on Athlon 64, Opteron, Phenom
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;     and Intel EM64T on Pentium 4 with EM64T, Pentium D, Core 2 Duo, Core I5/I7)
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; Copyright (C) 1995-2010 Jean-loup Gailly, Brian Raiter and Gilles Vollant.
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;
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; File written by Gilles Vollant, by converting to assembly the longest_match
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;  from Jean-loup Gailly in deflate.c of zLib and infoZip zip.
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;
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;  and by taking inspiration on asm686 with masm, optimised assembly code
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;        from Brian Raiter, written 1998
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;
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;  This software is provided 'as-is', without any express or implied
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;  warranty.  In no event will the authors be held liable for any damages
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;  arising from the use of this software.
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;
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;  Permission is granted to anyone to use this software for any purpose,
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;  including commercial applications, and to alter it and redistribute it
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;  freely, subject to the following restrictions:
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;
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;  1. The origin of this software must not be misrepresented; you must not
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;     claim that you wrote the original software. If you use this software
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;     in a product, an acknowledgment in the product documentation would be
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;     appreciated but is not required.
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;  2. Altered source versions must be plainly marked as such, and must not be
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;     misrepresented as being the original software
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;  3. This notice may not be removed or altered from any source distribution.
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;
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;
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;
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;         http://www.zlib.net
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;         http://www.winimage.com/zLibDll
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;         http://www.muppetlabs.com/~breadbox/software/assembly.html
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;
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; to compile this file for infozip Zip, I use option:
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;   ml64.exe /Flgvmat64 /c /Zi /DINFOZIP gvmat64.asm
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;
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; to compile this file for zLib, I use option:
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;   ml64.exe /Flgvmat64 /c /Zi gvmat64.asm
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; Be carrefull to adapt zlib1222add below to your version of zLib
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;   (if you use a version of zLib before 1.0.4 or after 1.2.2.2, change
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;    value of zlib1222add later)
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;
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; This file compile with Microsoft Macro Assembler (x64) for AMD64
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;
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;   ml64.exe is given with Visual Studio 2005/2008/2010 and Windows WDK
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;
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;   (you can get Windows WDK with ml64 for AMD64 from
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;      http://www.microsoft.com/whdc/Devtools/wdk/default.mspx for low price)
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;
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;uInt longest_match(s, cur_match)
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;    deflate_state *s;
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;    IPos cur_match;                             /* current match */
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.code
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longest_match PROC
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;LocalVarsSize   equ 88
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 LocalVarsSize   equ 72
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; register used : rax,rbx,rcx,rdx,rsi,rdi,r8,r9,r10,r11,r12
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; free register :  r14,r15
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; register can be saved : rsp
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 chainlenwmask   equ  rsp + 8 - LocalVarsSize    ; high word: current chain len
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                                                 ; low word: s->wmask
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;window          equ  rsp + xx - LocalVarsSize   ; local copy of s->window ; stored in r10
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;windowbestlen   equ  rsp + xx - LocalVarsSize   ; s->window + bestlen , use r10+r11
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;scanstart       equ  rsp + xx - LocalVarsSize   ; first two bytes of string ; stored in r12w
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;scanend         equ  rsp + xx - LocalVarsSize   ; last two bytes of string use ebx
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;scanalign       equ  rsp + xx - LocalVarsSize   ; dword-misalignment of string r13
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;bestlen         equ  rsp + xx - LocalVarsSize   ; size of best match so far -> r11d
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;scan            equ  rsp + xx - LocalVarsSize   ; ptr to string wanting match -> r9
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IFDEF INFOZIP
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ELSE
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 nicematch       equ  (rsp + 16 - LocalVarsSize) ; a good enough match size
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ENDIF
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save_rdi        equ  rsp + 24 - LocalVarsSize
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save_rsi        equ  rsp + 32 - LocalVarsSize
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save_rbx        equ  rsp + 40 - LocalVarsSize
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save_rbp        equ  rsp + 48 - LocalVarsSize
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save_r12        equ  rsp + 56 - LocalVarsSize
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save_r13        equ  rsp + 64 - LocalVarsSize
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;save_r14        equ  rsp + 72 - LocalVarsSize
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;save_r15        equ  rsp + 80 - LocalVarsSize
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; summary of register usage
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; scanend     ebx
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; scanendw    bx
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; chainlenwmask   edx
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; curmatch    rsi
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; curmatchd   esi
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; windowbestlen   r8
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; scanalign   r9
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; scanalignd  r9d
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; window      r10
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; bestlen     r11
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; bestlend    r11d
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; scanstart   r12d
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; scanstartw  r12w
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; scan        r13
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; nicematch   r14d
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; limit       r15
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; limitd      r15d
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; prev        rcx
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;  all the +4 offsets are due to the addition of pending_buf_size (in zlib
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;  in the deflate_state structure since the asm code was first written
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;  (if you compile with zlib 1.0.4 or older, remove the +4).
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;  Note : these value are good with a 8 bytes boundary pack structure
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    MAX_MATCH           equ     258
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    MIN_MATCH           equ     3
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    MIN_LOOKAHEAD       equ     (MAX_MATCH+MIN_MATCH+1)
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;;; Offsets for fields in the deflate_state structure. These numbers
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;;; are calculated from the definition of deflate_state, with the
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;;; assumption that the compiler will dword-align the fields. (Thus,
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;;; changing the definition of deflate_state could easily cause this
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;;; program to crash horribly, without so much as a warning at
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;;; compile time. Sigh.)
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;  all the +zlib1222add offsets are due to the addition of fields
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;  in zlib in the deflate_state structure since the asm code was first written
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;  (if you compile with zlib 1.0.4 or older, use "zlib1222add equ (-4)").
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;  (if you compile with zlib between 1.0.5 and 1.2.2.1, use "zlib1222add equ 0").
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;  if you compile with zlib 1.2.2.2 or later , use "zlib1222add equ 8").
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IFDEF INFOZIP
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_DATA   SEGMENT
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COMM    window_size:DWORD
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; WMask ; 7fff
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COMM    window:BYTE:010040H
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COMM    prev:WORD:08000H
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; MatchLen : unused
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; PrevMatch : unused
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COMM    strstart:DWORD
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COMM    match_start:DWORD
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; Lookahead : ignore
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COMM    prev_length:DWORD ; PrevLen
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COMM    max_chain_length:DWORD
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COMM    good_match:DWORD
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COMM    nice_match:DWORD
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prev_ad equ OFFSET prev
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window_ad equ OFFSET window
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nicematch equ nice_match
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_DATA ENDS
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WMask equ 07fffh
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ELSE
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  IFNDEF zlib1222add
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    zlib1222add equ 8
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  ENDIF
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dsWSize         equ 56+zlib1222add+(zlib1222add/2)
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dsWMask         equ 64+zlib1222add+(zlib1222add/2)
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dsWindow        equ 72+zlib1222add
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dsPrev          equ 88+zlib1222add
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dsMatchLen      equ 128+zlib1222add
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dsPrevMatch     equ 132+zlib1222add
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dsStrStart      equ 140+zlib1222add
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dsMatchStart    equ 144+zlib1222add
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dsLookahead     equ 148+zlib1222add
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dsPrevLen       equ 152+zlib1222add
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dsMaxChainLen   equ 156+zlib1222add
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dsGoodMatch     equ 172+zlib1222add
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dsNiceMatch     equ 176+zlib1222add
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window_size     equ [ rcx + dsWSize]
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WMask           equ [ rcx + dsWMask]
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window_ad       equ [ rcx + dsWindow]
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prev_ad         equ [ rcx + dsPrev]
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strstart        equ [ rcx + dsStrStart]
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match_start     equ [ rcx + dsMatchStart]
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Lookahead       equ [ rcx + dsLookahead] ; 0ffffffffh on infozip
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prev_length     equ [ rcx + dsPrevLen]
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max_chain_length equ [ rcx + dsMaxChainLen]
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good_match      equ [ rcx + dsGoodMatch]
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nice_match      equ [ rcx + dsNiceMatch]
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ENDIF
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; parameter 1 in r8(deflate state s), param 2 in rdx (cur match)
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; see http://weblogs.asp.net/oldnewthing/archive/2004/01/14/58579.aspx and
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; http://msdn.microsoft.com/library/en-us/kmarch/hh/kmarch/64bitAMD_8e951dd2-ee77-4728-8702-55ce4b5dd24a.xml.asp
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;
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; All registers must be preserved across the call, except for
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;   rax, rcx, rdx, r8, r9, r10, and r11, which are scratch.
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;;; Save registers that the compiler may be using, and adjust esp to
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;;; make room for our stack frame.
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;;; Retrieve the function arguments. r8d will hold cur_match
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;;; throughout the entire function. edx will hold the pointer to the
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;;; deflate_state structure during the function's setup (before
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;;; entering the main loop.
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; parameter 1 in rcx (deflate_state* s), param 2 in edx -> r8 (cur match)
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; this clear high 32 bits of r8, which can be garbage in both r8 and rdx
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        mov [save_rdi],rdi
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        mov [save_rsi],rsi
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        mov [save_rbx],rbx
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        mov [save_rbp],rbp
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IFDEF INFOZIP
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        mov r8d,ecx
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ELSE
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        mov r8d,edx
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ENDIF
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        mov [save_r12],r12
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        mov [save_r13],r13
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;        mov [save_r14],r14
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;        mov [save_r15],r15
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;;; uInt wmask = s->w_mask;
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;;; unsigned chain_length = s->max_chain_length;
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;;; if (s->prev_length >= s->good_match) {
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;;;     chain_length >>= 2;
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;;; }
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        mov edi, prev_length
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        mov esi, good_match
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        mov eax, WMask
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        mov ebx, max_chain_length
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        cmp edi, esi
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        jl  LastMatchGood
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        shr ebx, 2
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LastMatchGood:
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;;; chainlen is decremented once beforehand so that the function can
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;;; use the sign flag instead of the zero flag for the exit test.
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;;; It is then shifted into the high word, to make room for the wmask
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;;; value, which it will always accompany.
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        dec ebx
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        shl ebx, 16
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        or  ebx, eax
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;;; on zlib only
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;;; if ((uInt)nice_match > s->lookahead) nice_match = s->lookahead;
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IFDEF INFOZIP
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        mov [chainlenwmask], ebx
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; on infozip nice_match = [nice_match]
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ELSE
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        mov eax, nice_match
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        mov [chainlenwmask], ebx
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        mov r10d, Lookahead
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        cmp r10d, eax
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        cmovnl r10d, eax
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        mov [nicematch],r10d
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ENDIF
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;;; register Bytef *scan = s->window + s->strstart;
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        mov r10, window_ad
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        mov ebp, strstart
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        lea r13, [r10 + rbp]
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;;; Determine how many bytes the scan ptr is off from being
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;;; dword-aligned.
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         mov r9,r13
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         neg r13
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         and r13,3
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;;; IPos limit = s->strstart > (IPos)MAX_DIST(s) ?
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;;;     s->strstart - (IPos)MAX_DIST(s) : NIL;
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IFDEF INFOZIP
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        mov eax,07efah ; MAX_DIST = (WSIZE-MIN_LOOKAHEAD) (0x8000-(3+8+1))
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ELSE
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        mov eax, window_size
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        sub eax, MIN_LOOKAHEAD
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ENDIF
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        xor edi,edi
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        sub ebp, eax
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        mov r11d, prev_length
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        cmovng ebp,edi
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;;; int best_len = s->prev_length;
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;;; Store the sum of s->window + best_len in esi locally, and in esi.
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       lea  rsi,[r10+r11]
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;;; register ush scan_start = *(ushf*)scan;
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;;; register ush scan_end   = *(ushf*)(scan+best_len-1);
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;;; Posf *prev = s->prev;
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        movzx r12d,word ptr [r9]
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        movzx ebx, word ptr [r9 + r11 - 1]
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        mov rdi, prev_ad
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;;; Jump into the main loop.
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        mov edx, [chainlenwmask]
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        cmp bx,word ptr [rsi + r8 - 1]
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        jz  LookupLoopIsZero
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LookupLoop1:
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        and r8d, edx
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        movzx   r8d, word ptr [rdi + r8*2]
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        cmp r8d, ebp
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        jbe LeaveNow
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        sub edx, 00010000h
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        js  LeaveNow
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LoopEntry1:
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        cmp bx,word ptr [rsi + r8 - 1]
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        jz  LookupLoopIsZero
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LookupLoop2:
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        and r8d, edx
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        movzx   r8d, word ptr [rdi + r8*2]
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        cmp r8d, ebp
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        jbe LeaveNow
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        sub edx, 00010000h
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        js  LeaveNow
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LoopEntry2:
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        cmp bx,word ptr [rsi + r8 - 1]
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        jz  LookupLoopIsZero
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LookupLoop4:
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        and r8d, edx
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        movzx   r8d, word ptr [rdi + r8*2]
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        cmp r8d, ebp
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        jbe LeaveNow
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        sub edx, 00010000h
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        js  LeaveNow
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LoopEntry4:
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        cmp bx,word ptr [rsi + r8 - 1]
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        jnz LookupLoop1
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        jmp LookupLoopIsZero
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;;; do {
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;;;     match = s->window + cur_match;
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;;;     if (*(ushf*)(match+best_len-1) != scan_end ||
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;;;         *(ushf*)match != scan_start) continue;
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;;;     [...]
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;;; } while ((cur_match = prev[cur_match & wmask]) > limit
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;;;          && --chain_length != 0);
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;;;
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;;; Here is the inner loop of the function. The function will spend the
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;;; majority of its time in this loop, and majority of that time will
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;;; be spent in the first ten instructions.
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;;;
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;;; Within this loop:
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;;; ebx = scanend
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;;; r8d = curmatch
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;;; edx = chainlenwmask - i.e., ((chainlen << 16) | wmask)
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;;; esi = windowbestlen - i.e., (window + bestlen)
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;;; edi = prev
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;;; ebp = limit
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LookupLoop:
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        and r8d, edx
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        movzx   r8d, word ptr [rdi + r8*2]
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        cmp r8d, ebp
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        jbe LeaveNow
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        sub edx, 00010000h
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        js  LeaveNow
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LoopEntry:
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        cmp bx,word ptr [rsi + r8 - 1]
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        jnz LookupLoop1
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LookupLoopIsZero:
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        cmp     r12w, word ptr [r10 + r8]
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        jnz LookupLoop1
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;;; Store the current value of chainlen.
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        mov [chainlenwmask], edx
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;;; Point edi to the string under scrutiny, and esi to the string we
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;;; are hoping to match it up with. In actuality, esi and edi are
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;;; both pointed (MAX_MATCH_8 - scanalign) bytes ahead, and edx is
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;;; initialized to -(MAX_MATCH_8 - scanalign).
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        lea rsi,[r8+r10]
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        mov rdx, 0fffffffffffffef8h; -(MAX_MATCH_8)
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        lea rsi, [rsi + r13 + 0108h] ;MAX_MATCH_8]
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        lea rdi, [r9 + r13 + 0108h] ;MAX_MATCH_8]
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        prefetcht1 [rsi+rdx]
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        prefetcht1 [rdi+rdx]
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;;; Test the strings for equality, 8 bytes at a time. At the end,
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;;; adjust rdx so that it is offset to the exact byte that mismatched.
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;;;
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;;; We already know at this point that the first three bytes of the
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;;; strings match each other, and they can be safely passed over before
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;;; starting the compare loop. So what this code does is skip over 0-3
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;;; bytes, as much as necessary in order to dword-align the edi
 | 
						|
;;; pointer. (rsi 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 rax, [rsi + rdx]
 | 
						|
        xor rax, [rdi + rdx]
 | 
						|
        jnz LeaveLoopCmps
 | 
						|
 | 
						|
        mov rax, [rsi + rdx + 8]
 | 
						|
        xor rax, [rdi + rdx + 8]
 | 
						|
        jnz LeaveLoopCmps8
 | 
						|
 | 
						|
 | 
						|
        mov rax, [rsi + rdx + 8+8]
 | 
						|
        xor rax, [rdi + rdx + 8+8]
 | 
						|
        jnz LeaveLoopCmps16
 | 
						|
 | 
						|
        add rdx,8+8+8
 | 
						|
 | 
						|
        jnz short LoopCmps
 | 
						|
        jmp short LenMaximum
 | 
						|
LeaveLoopCmps16: add rdx,8
 | 
						|
LeaveLoopCmps8: add rdx,8
 | 
						|
LeaveLoopCmps:
 | 
						|
 | 
						|
        test    eax, 0000FFFFh
 | 
						|
        jnz LenLower
 | 
						|
 | 
						|
        test eax,0ffffffffh
 | 
						|
 | 
						|
        jnz LenLower32
 | 
						|
 | 
						|
        add rdx,4
 | 
						|
        shr rax,32
 | 
						|
        or ax,ax
 | 
						|
        jnz LenLower
 | 
						|
 | 
						|
LenLower32:
 | 
						|
        shr eax,16
 | 
						|
        add rdx,2
 | 
						|
LenLower:   sub al, 1
 | 
						|
        adc rdx, 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 rax, [rdi + rdx]
 | 
						|
        sub rax, r9
 | 
						|
        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.
 | 
						|
;///////////////////////////////////
 | 
						|
 | 
						|
        cmp eax, r11d
 | 
						|
        jg  LongerMatch
 | 
						|
 | 
						|
        lea rsi,[r10+r11]
 | 
						|
 | 
						|
        mov rdi, prev_ad
 | 
						|
        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 r11d, eax
 | 
						|
        mov match_start, r8d
 | 
						|
        cmp eax, [nicematch]
 | 
						|
        jge LeaveNow
 | 
						|
 | 
						|
        lea rsi,[r10+rax]
 | 
						|
 | 
						|
        movzx   ebx, word ptr [r9 + rax - 1]
 | 
						|
        mov rdi, prev_ad
 | 
						|
        mov edx, [chainlenwmask]
 | 
						|
        jmp LookupLoop
 | 
						|
 | 
						|
;;; Accept the current string, with the maximum possible length.
 | 
						|
 | 
						|
LenMaximum:
 | 
						|
        mov r11d,MAX_MATCH
 | 
						|
        mov match_start, r8d
 | 
						|
 | 
						|
;;; if ((uInt)best_len <= s->lookahead) return (uInt)best_len;
 | 
						|
;;; return s->lookahead;
 | 
						|
 | 
						|
LeaveNow:
 | 
						|
IFDEF INFOZIP
 | 
						|
        mov eax,r11d
 | 
						|
ELSE
 | 
						|
        mov eax, Lookahead
 | 
						|
        cmp r11d, eax
 | 
						|
        cmovng eax, r11d
 | 
						|
ENDIF
 | 
						|
 | 
						|
;;; Restore the stack and return from whence we came.
 | 
						|
 | 
						|
 | 
						|
        mov rsi,[save_rsi]
 | 
						|
        mov rdi,[save_rdi]
 | 
						|
        mov rbx,[save_rbx]
 | 
						|
        mov rbp,[save_rbp]
 | 
						|
        mov r12,[save_r12]
 | 
						|
        mov r13,[save_r13]
 | 
						|
;        mov r14,[save_r14]
 | 
						|
;        mov r15,[save_r15]
 | 
						|
 | 
						|
 | 
						|
        ret 0
 | 
						|
; please don't remove this string !
 | 
						|
; Your can freely use gvmat64 in any free or commercial app
 | 
						|
; but it is far better don't remove the string in the binary!
 | 
						|
    db     0dh,0ah,"asm686 with masm, optimised assembly code from Brian Raiter, written 1998, converted to amd 64 by Gilles Vollant 2005",0dh,0ah,0
 | 
						|
longest_match   ENDP
 | 
						|
 | 
						|
match_init PROC
 | 
						|
  ret 0
 | 
						|
match_init ENDP
 | 
						|
 | 
						|
 | 
						|
END
 |