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