.xX\$\$x. .x\$\$\$\$\$\$\$x. d\$\$\$\$\$\$\$\$\$\$\$ ,\$\$\$\$\$\$\$P' `P' , . \$\$\$\$\$\$P' ' .d b \$\$\$\$\$P b ,\$\$x ,\$\$x ,\$\$x ,\$\$b \$\$. Y\$\$\$\$' `\$. \$\$\$\$\$\$. \$\$\$\$\$\$ \$\$P~d\$. d\$\$\$b d d\$\$\$ `\$\$\$\$ ,\$\$ \$\$\$\$\$\$\$b \$\$\$P `\$ \$\$\$b.\$\$b `Y\$\$\$d\$d\$\$\$' . . a . a a .aa . a `\$\$\$ ,\$\$\$,\$\$' `\$\$\$ \$\$\$' ' \$\$P\$XX\$' `\$\$\$\$\$\$\$\$\$ .dP' `\$'\$ `\$'\$ , \$''\$ `\$'\$ `Y\$b ,d\$\$\$P `\$b,d\$P' `\$\$. `\$\$. , `\$\$P \$\$\$' Y \$. \$ \$ \$ Y..P \$ `\$\$\$\$\$\$\$' \$\$\$P' `\$\$b `\$\$\$P `P `\$' `Y'k. \$. \$. \$. \$\$' \$. Issue 7 November 27, 1995 ______________________________________________________________________________ Core_Warrior_ is a weekly newsletter promoting the game of corewar. Emphasis is placed on the most active hills--currently the '94 draft hill and the beginner hill. Coverage will follow where ever the action is. If you have no clue what I'm talking about then check out these five-star internet locals for more information: FAQs are available by anonymous FTP from rtfm.mit.edu as pub/usenet/news.answers/games/corewar-faq.Z FTP site is: ftp.csua.berkeley.edu /pub/corewar Web pages are at: http://www.stormking.com/~koth ;Stormking http://www.ecst.csuchico.edu/~pizza/koth ;Pizza http://pauillac.inria.fr/~doligez/corewar/ ;Planar ______________________________________________________________________________ Greetings. This week there is another juicy, at least in my hopes, number of Core warrior. The hint will cover bombers and bombs, including Paul Kline's contribute and Torch 18 code; Robert Mcrae introduces you to quickscannes secrets and Planar finishes the continual launch imps topic, and unveils his new warrior Impfinity 3i. Many thanks to them and to all contributing to the newsletter. Last minute new: big (CORESIZE 55440) hill has been reopened at Stormking server, address: ;redcode-94x Enjoy it and many thanks Tuc. ______________________________________________________________________________ Current Status of the Internet Pizza Server ICWS '94 Draft Hill: # %W/ %L/ %T Name Author Score Age 1 47/ 38/ 14 quiz Schitzo 156 78 2 43/ 34/ 23 test lp 2 Beppe Bezzi 152 4 3 38/ 25/ 37 La Bomba Beppe Bezzi 151 73 4 43/ 36/ 22 Derision M R Bremer 150 97 5 37/ 31/ 32 Torch t18 P.Kline 143 457 6 37/ 39/ 24 myVamp v3.7 Paulsson 135 425 7 36/ 37/ 27 endpoint . M R Bremer 134 102 8 38/ 43/ 19 Porch Swing + Randy Graham 134 158 9 26/ 20/ 54 Fly Fishing w/Plastic Wor Karl Lewin 131 55 10 38/ 45/ 17 Frontwards Steven Morrell 131 5 11 33/ 35/ 32 Phq Maurizio Vittuari 131 559 12 40/ 48/ 13 Leprechaun on speed Anders Ivner 131 253 13 33/ 35/ 32 Son & Father Maurizio Vittuari 130 108 14 36/ 44/ 20 myZizzor v2.0 Paulsson 128 8 15 27/ 27/ 46 Jack in the box Beppe Bezzi 128 445 16 20/ 12/ 67 Impfinity v3i Planar 128 7 17 31/ 34/ 36 Father & Son Maurizio Vittuari 127 107 18 33/ 41/ 25 Armory - A5 Wilkinson 126 596 19 24/ 22/ 54 juliet and paper M R Bremer, B. Bezzi 125 74 20 19/ 21/ 60 test4 Kurt Franke 118 1 After last week revolution we had a quiet one. Very little to report: quiz takes the head even if La Bomba is still in top positions, Morrell and Paulsson submitted new version of their warriors pushed off last week. Planar's new Impfinity enters the hill, you can see the code in Planar's corner, Kline attempted a new p-spacer without success. In the bottom Armory is shuffling a bit, but still resists junger warrior challenges. Franke, one of beginners hill top scorers, enters the bottom of 94 ______________________________________________________________________________ 94 - What's New 11 39/ 43/ 19 myZizzor v2.0 Paulsson 135 1 10 23/ 13/ 64 Impfinity v3i Planar 133 1 19 37/ 47/ 16 Frontwards Steven Morrell 128 1 20 19/ 21/ 60 test4 Kurt Franke 118 1 ______________________________________________________________________________ 94 - What's No More 21 34/ 49/ 17 Scissors v.a1 John K. Wilkinson 119 28 21 31/ 50/ 19 Scissors v.a4 John K. Wilkinson 113 4 21 20/ 17/ 63 TimeScape (1.7) J. Pohjalainen 122 17 21 14/ 11/ 75 Evolve 6.3 John Wilkinson 118 24 The calm after the tempest, no aged warrior has been pushed off. ______________________________________________________________________________ What's old 18 33/ 41/ 25 Armory - A5 Wilkinson 126 596 11 33/ 35/ 32 Phq Maurizio Vittuari 131 559 5 37/ 31/ 32 Torch t18 P.Kline 143 457 15 27/ 27/ 46 Jack in the box Beppe Bezzi 128 445 6 37/ 39/ 24 myVamp v3.7 Paulsson 135 425 12 40/ 48/ 13 Leprechaun on speed Anders Ivner 131 253 Veterans surviving last week carnage improve their scores a little. Armory and Jack in the box are having some problems, while Torch and myVamp are still very effective. _____________________________________________________________________________ Current Status of the Internet Pizza Server Beginner's Hill: # %W/ %L/ %T Name Author Score Age 1 45/ 35/ 20 Clear Sighted v1 JS Pulido 156 3 2 45/ 38/ 18 dualstrat v.0.2 Brian Haskin 152 2 3 36/ 22/ 41 teamwork? Kurt Franke 150 23 4 44/ 39/ 17 Fire Master v1.5 JS Pulido 148 6 5 36/ 33/ 31 Lurker 1.1 Kurt Franke 139 21 6 33/ 29/ 38 test L 9 Beppe Bezzi 136 4 7 26/ 20/ 54 Schizo J. Doster 132 53 8 31/ 31/ 38 Hint Test v4 M R Bremer 131 19 9 21/ 12/ 67 Impfinity v3c11 Planar 130 65 10 21/ 21/ 58 Trapper 1.1 Kurt Franke 121 1 11 20/ 19/ 61 Paper8-III G. Eadon 120 11 12 32/ 45/ 23 Look J. Doster 120 50 13 19/ 18/ 64 Sheet 1.0 J. Doster 120 63 14 14/ 9/ 77 RingWorm_v2.5 Calvin Loh 118 36 15 17/ 17/ 65 RingWorm_v2.4 Calvin Loh 118 51 16 12/ 7/ 81 Impfinity v1 Planar 116 97 17 28/ 41/ 31 Good old DJN Test Karl Lewin 115 16 18 20/ 26/ 53 Loh_tst_1.3 Calvin Loh 114 26 19 10/ 9/ 81 NewerPaper Kurt Franke 111 17 20 27/ 45/ 28 Paper Shredder 2.1 Kurt Franke 108 20 The very active beginners hill shows five new entries in the top ten positions. Pulido, Haskin and Franke seem ready to make the jump to veterans. Bezzi, a new author, at least from when I'm following beginners, enters in 6th position with a warrior that was 3rd in 94 hill :-) The morale of the story is that: The beginners hill level has grown in these weeks, perhaps it's higher than ever. All those who have a warrior doing well in -b hill have to try the -94, at worst you'll score 90 points finding 94 hill hostile to the warrior kind you are submitting, but with a little luck you can enter and begin making experience. _____________________________________________________________________________ HALL OF FAME * means the warrior is still running. Pos Name Author Age Strategy 1 Iron Gate 1.5 Wayne Sheppard 926 CMP scanner 2 Agony II Stefan Strack 912 CMP scanner 3 Blue Funk Steven Morrell 869 Stone/ imp 4 Thermite 1.0 Robert Macrae 802 Qscan -> bomber 5 Blue Funk 3 Steven Morrell 766 Stone/ imp 6 HeremScimitar A.Ivner,P.Kline 666 Bomber 7 Armory - A5 Wilkinson 596 * P-warrior 8 Phq Maurizio Vittuari 559 * Qscan -> replicator 9 B-Panama X Steven Morrell 518 Stone/ replicator 10 Torch t18 P.Kline 457 * Bomber 11 Jack in the box Beppe Bezzi 445 * P-warrior 12 myVamp v3.7 Paulsson 425 * Vampire 13 NC 94 Wayne Sheppard 387 Stone/ imp 14 Cannonade P.Kline 382 Stone/ imp 15 Torch t17 P.Kline 378 Bomber 16 Lucky 3 Stefan Strack 355 Stone/ imp 17 Request v2.0 Brant D. Thomsen 347 Qvamp -> vampire 18 Dragon Spear c w blue 346 CMP scanner 19 juliet storm M R Bremer 333 Stone/ imp 20 Frontwards Steven Morrell 323 One shot scanner Armory, very near 600 age now, and Phq consolidate their position in the hall of fame; Torch enters top ten trailing Jack and myVamp, all three well over 400 age. Frontwards enters bottom place pushing Timescape off. ______________________________________________________________________________ The Hint Hello folks, last week Myers introduced the bomber topic with two classic stones, Blue Funk and juliet storm; these guys are four-five lines long, and found their effectiveness on their small size and resilience more than on speed, they are both at 33% c, one bomb every three cycles, and effectiveness of their bombs, simple dat 0,0. There is another category of more complex bombers that balance the increased size with a greater speed and/or deadlier bombs. Who better than Paul Kline, Torch's author, can speak of this argument. ---------- Your basic 'stone' bomber is based on this fragment: incr spl #step,#-step <- self-splitter add incr,1 <- step up the pointers mov <0,0 <- decrement one and bomb the other djn -2,<-10 <- loop and sequential decrement Steven Morrell's discussion last issue showed how to optimize this for maximum bombing duration, but his comment about Emerald is too generous. I never realized or designed Emerald's pattern, it was just the best of a large number of step sizes I tried. Anyway, the above delivers one decrement and one bomb in three cycles. However it is possible for the opponent to immunify part of his code to decrements, and thereby reduce this bomber to something much less than 66% effective speed. A search through old programs (still a gold mine!) turns up this one by Paul Kilroy: ;name Ike v.21 ;author Paul S. Kilroy ;strategy A bomber with a cool twist bomb spl 0 ,jump ptr dat #0 ,#0 inc add #468,b start jmz inc ,@b b mov bomb,@464 mov bomb,@b jump jmp inc mov 10 ,<-2 end start Which is your basic spl-bombing b-scanner with, as he says "a cool twist". When he finds a non-zero location he uses it as a pointer and bombs through it, then bombs the found location. In other words, bombing two locations without an intermediate ADD. I was wanting to make this a pure non-scanning bomber, which is easy enough. But the results were not exceptional. With this code you get a nice 50% hard bomber: bomber add #step+step,2 mov bomb,@1 mov bomb,@0 jmp bomber bomb dat #0,step Unfortunately it is a little bigger than the 4-line version and not quite as fast, even though it delivers real bombs instead of decrements. It becomes a little more durable with a leading SPL which keeps single dat-bombs from killing it. And it still loses completely to paper. Anders Ivner's HeremII uses similar code to drop alternating spl and dat-bombs that are very widely spaced in core. HeremII works somewhat against old style paper, but is helpless against Silk. To kill paper requires some kind of spl-bomb that slows it down enough to give a sequential clear time to wipe the whole core. A split-carpet like Agony's works very well, but this bombing routine won't accomodate one. A spl-jmp could be delivered by alternating spl's and jmp's, with an eventual wrap-around to match spl's to jmp's. But single spl's and single jmp's are not only useless against today's paper, they are actually dangerous, since they can mutate the opponent into a whole lot of sequential core-clear/bombers. Enter the mov-spl ('incendiary') bomb, which is a little two-line program that you drop on the opponent causing him to write and execute his own spl-carpet. The important feature of this bomb is that the components can be well separated - hence alternating bombs. Here is the working part of Torch 18, which bombs extensively with mov-spl bombs, does one core wipe with a spl, then goes into a repeating forward core-clear with dat. It also has a nice feature in that if it is overrun with a djn-stream it immediately starts the forward dat-clear process, usually killing the nasty opponent. gate dat 0,0 for 3 dat 0,0 rof w2 dat -7,cp-gate+3 dat 0,0 wipe dat -7,cp-gate+3 sp spl #-1-step,-step ; spl half of the incendiary in sub #step+step,@msp msm mov sm,*tgt+(step*count)-17228 msp mov sp,@msm ; bomb alternately with spl & mov tgt jmz in,#0 ; bombed with spl to start clear clr mov @cp,>gate cp djn.b clr,{wipe+1 for 2 dat 0,0 rof sm mov step+1,>step+1 ; mov half of the incendiary Notice that in the inner loop the instructions are reversed from the example - instructions following a SPL execute in reverse order. Torch is bigger than a 4-line stone and will lose most of those battles. However, those stones are paper-bait even with supporting imps while Torch has the punch to stay on the Hill. The current version also uses a decoy to foil programs like Withershins Thrice and Porch Swing. Questions for thought: What is the best 1-line bomb? What is the best 2-line bomb? What is the best 3-line bomb? Answer correctly and you could go straight to the top of the heap .. uh Hill! Paul Kline pk6811s@acad.drake.edu ---------- Let's speak a bit of bombs; what is the best possible bomb? The answer to this question is another question: who are you shooting at? If our enemy is a single process, long warrior like a scanner the answer is easy, no bomb at all... yes no bomb, taking a cell from somewhere in the core, usually a dat 0,0 and throwing it in the middle of our enemy is enough to kill him, and we have no need to include the bomb in our code, reducing our size. This is the approach of Blue Funk and juliet. If our enemy is a replicator this is pointless; we have no chance to kill all paper bodies at the rate they spread. To kill them we have to slow them first and, at the end deliver our deadly blow at wounded enemy, yes a very evil act :-) This can be accomplished with more complex bombs either spl 0 followed by jmp -1, as Iron gate does when it finds a target, or with the so called incendiary, mov step, >step ;alternated with spl 0, -step+1 when the mov is executed it take the spl, step cells away, and moves it immediatly after the mov itself; if the mov is executed by a multiprocess paper the effect is creating a spl carpet. Devastating indeed. If our enemy is a coreclear, something with a very reduced footprint like: gate dat -20,20 wipe spl #-20,20 ... split spl 0,0 move mov @1,>gate jump djn -1,{wipe A dat 0,0 hit at the gate, split or jump instruction won't stop the clear running, we need something more effective like Tornado's bomb, (I have not invented it, it's due to Paul Kline if I'm not wrong, I just used it) mov step,1 ;step away there is another one Using this bomb we have added to our target the 'split' line and the 'gate' line, increasing our chances to kill. To finish bombers argument I'll introduce now Tornado, the faster pure bomber and, BTW, one of my favourite babies. It has never had a great success alone, its best version stayed on hill little more than 200 challenges, never climbing higher than 10th position, but proved very effective as component of successful warrior like Jack in the box. Tornado pushes the indirect bombing one step farther, he lays down two bombs and uses the second one as pointer for the third reaching a speed of 60% c, three bombs in a five instruction loop. This is the version included as scanner/clear killer in the p-warrior Jack in the box step equ 95 count equ 533 bomber mov bd, *stone mov bm @stone stone mov *step+2,*(2*step)+2 stone line is the hearth of the bomber. It can be changed slightly if we want to use bombs with fixed a or b fields of values different from the step What's important is that the bomb addressed by b field of stone had one of its fields with the value step add incr, stone jump djn.b bomber, #count Three bombs in a 5 instructions loop means 60% c speed, comparable with that of a cmp scanner (66%c) and without any problem of being delayed by decoys and bomb's color. In fact Tornado easily kills any scanner and clear incr spl #3*step,#3*step clr mov -12, }bomber+1 djmp jmp clr, clear to try catching imps, but is the best fit for the role of 'scanners/clears killer' in the p-warrior. Tweaking a litle the code Tornado can be armed with incendiary bombs too; the incendiary version has been submitted to the hill as Firestorm, and was included in the p-warrior Brain Wash. I won't tell you now, without a substantial payment to my bank account :-), what I have put in La Bomba, and how I use it; stay tuned near Christmas, with most chances I'll make you a gift. For next hint I'm waiting your suggestions. ______________________________________________________________________________ Tournament Time (details at http://www.stormking.com/~koth/nsfcwt.html) No tournament round this week, Thanksgiving break. This is the rank after round 6: Name 1 2 3 4 5 6 total Steven Morrell 5 10 9 13 14 10 61 P.Kline 7.5 9 7 11 11 12 57.5 Paulsson 7.5 11 11 9 2 5 45.5 Anders Ivner 5.5 8 4 0 10 14 41.5 Beppe Bezzi 7 7 13 2 8 3 40 M R Bremer 7 4 3.6 5 7 11 37.6 Maurizio Vittuari 6.5 5 6 3 9 8 37.5 John K. Wilkinson 4 6 12 0 13 2 37 Robert Macrae 0 0 0 12 12 13 37 Karl Lewin 0 0 10 4 6 10 30 Randy Graham 0 0 8 10 4 7 29 Derek Ross 3.5 3 3.3 7 3 6 25.8 G. Eadon 1.5 2 5 6 1 4 19.5 Kurt Franke 0 0 0 8 0 0 8 Michael Constant 0 0 0 0 5 0 5 Anders Scholl 0 1 2 1 0 0 4 John Lewis 0 0 3 0 0 0 3 Calvin Loh 0 0 1 0 0 1 2 ______________________________________________________________________________ Planar's Corner: Continuous imp-launching (final part) Impfinity v1 is now close to dying of old age, after being published in Core Warrior 4 and spending most of its life in the bottom half of the beginner hill. I was writing version 2 when I realized that binary launching is not the only way of launching a continuous spiral. The JMP/ADD launch can also be adapted. I'll first explain JMP/ADD launching. Old-timers may want to skip three paragraphs. This is a JMP/ADD launcher, taken from the FAQ: A spl 1, 0 B spl 1, 0 C spl E, 0 D jmp imp, 0 E add.a #step, D F dat 0, 0 imp mov.i #0, step This is how it works: [A] [B B] [C C C C] [D E D E D E D E] [imp F imp+step F imp+2*step F imp+3*step F] [imp+1 imp+step+1 imp+2*step+1 imp+3*step+1] It's pretty straightforward: we interleave processes at D and E, the processes at D jump to the spiral, and the processes at E increment the JMP at D to make it point to the right place for each jump. How do we convert this into a continuous launch ? We have to alternate ADDs and JMPs. The easiest way to do it: Z spl 0, 0 A add.a #step+1, J J jmp imp-step-1, 0 Here is what it does: [Z] [A Z] [J A Z] [imp J A Z] [imp+1 imp+step+1 J A Z] So this code will alternate ADDs and JMPs and add one process to the spiral at each turn. We have to ADD step+1 because the spiral will advance by one location before we add a process. The above piece of code is what I call the "pump", because it pumps processes into the spiral. There's one little problem because the pump only adds one process per round. An incomplete spiral is not viable, its processes will die within one round. So we have to keep the spiral alive until the first ring is completed. There are several ways of doing this. I've considered launching a complete ring with one of the three classical launchers, and synchronizing the pump to add processes at the right place. Finally, I've decided to use a little piece of code to prime the pump: instr mov.i #0, step primer spl 0, >1 mov.i instr, imp This will unroll a carpet of imp instructions under the tail of the spiral. If you locate the primer at the right place in front of the spiral, it will be overwritten by the spiral when its job is finished (or you can arrange for your stone to kill it, or whatever). Note that you have to do one MOV in each turn. A DJN loop will not work here. So this is it. Six lines of code, three of them can be located away from the three others, and they are only used for a few dozen cycles. What is left for scanners to find is just three lines. Pretty good, no ? A few ideas occured to me while I was writing this. I'll give them as exercises to the reader: - There may be a way of launching several processes per round with something like this: Z spl Z, }J A spl 1, 0 B spl 1, 0 C spl E, 0 J jmp imp, 0 E add.a #step, J F dat 0, 0 imp mov.i #0, step This will add 4 processes to the imp in each round, so it doesn't need a primer for a 3-point imp. It launches faster but it's longer. - We could incorporate the primer into the pump (build an auto-prime pump ?) like this: Z spl 0, >P P mov.i imp, imp A add.a #step+1, J J jmp imp-step-1, 0 imp mov.i #0, step Hmm, I think I'm going to integrate something like this into a future version of Impfinity. - Because in a core of size 55440 imp spirals have at least 13 points, launchers tend to be bigger and easier to kill. This is not true for this launcher, so this technique may be more useful in the experimental hill. Finally, I'll give you the latest version of Impfinity. I've provided a reasonable set of constants that are completely different from what I've sent to the hill. Impfinity v3i implements the ideas given by Magnus Paulsson in Core Warrior 2 about how Die Hard might be working. We now know that Die Hard has nothing to do with Magnus' guesses, but his ideas are still good. I'll quote him: >Now if you place two spirals on top of each other, and plan in which order >they and the rest of the code will be in the execution. In the coreclear the >spl processes will be like 4000 processes, spiral, 4000 processes, spiral. >That means the clear has to kill spiral in 4000 cycles which isn't possible >in a clear. Right. And since scanners were the real danger for Impfinity, I've interleaved the two spirals with two self-splitting stones that eat most of the processes (because they will be stunned anyway). When one of the stone is stunned, the other one keeps going at about the same speed because it splits almost as fast as the stunned one. In the real world, it's more like 2000 processes, spiral, 6000 processes, spiral. But it does give better protection against core-clears. >So, because there is a thing called gate which kills spirals. In order to tie >you have to have something like 100 processes in a spiral to slow it down as >much that it doesn't reach the gate. Now you can't launch such a monster >without getting killed before the launch is complete. Aha, but with continuous launching, you can launch a monster of any size with a 3-line launcher that scanners (and stones) will find hard to kill. And because the self-splitting stones eat most of the cycles, 60 processes in the spirals are largely enough: by the time the stones are killed and the spirals advance at full speed, the game is almost over. Impfinity v3i starts with an SPL that divides the cycles in half. Each half is doing the same thing (but with different offsets): bootstrap the pump, primer, and stone; launch the pump and primer. The primer will launch the stone after a (short) while. If I start the stone too early, the spiral is too short (it doesn't grow much, once the stone is started). So we have two stones and two spirals. The spirals are exactly on top of each other, so they help keep each other alive. The stones are synchronized with magic01, magic02, stnof01, and stnof02, so they won't kill each other (or themselves) until very late, and one of them turns itself into a core-clear (one-pass, unfortunately). Oh, and I have a 7-point spiral, so I can use anti-3-point bombs, but I have no idea how much good it does. Finally, I think the stone design warrants a few words. It is self-splitting, changes 3 core locations in 4 cycles, throws colored bombs, and turns itself into a suicidal core-clear if you use the right magic constant. And I can make it switch bombs in the middle of the bombing run (not shown here). Is it original ? I don't know. A little bit of version history: Version 3e7, which stayed on the bottom half of the '94 hill for some time, didn't have the twin spirals and stones, and had a slower bootstrap. Version 3c11 (sent to the beginner hill after it failed to enter the '94 hill) has a slower stone and an 11-point spiral. I'll put them both on my Web page, along with version 3i, when this issue of Core Warrior is posted. ;redcode-94 ;name Impfinity v3i ;author Planar ;strategy boot,imp,stone,clear ;assert CORESIZE == 8000 ; The constants on the lines marked with "C" are all different ; from the version on the hill. ; To synchronize the two stones, I had to do a lot of tweaking of ; magic01, magic02, stnof01, and stnof02. Thanks to cdb, it only ; took a few hours. istep equ 1143 bstep01 equ 2214 bstep02 equ 3285 magic01 equ (-2) ; C magic02 equ (-3) ; C fuse equ 13 ; C trash equ (Z-200) ; C impoff equ (Z+500) ; C prmof01 equ (impoff+2*istep+20) ; C prmof02 equ (impoff+5*istep+20) ; C pmpof01 equ (impoff+4*istep-20) ; C pmpof02 equ (impoff+1*istep-20) ; C stnof01 equ (impoff+3*istep-21) ; C stnof02 equ (impoff+6*istep-19) ; C org boot Z boot spl boot02 i FOR 2 boot&i mov.i {ppmp&i, trash-15-i*2, pstn&i spl @ppmp&i, >pprm&i mov.i >trash-i*2, ppmp&i spl @pprm&i, >trash-5-i*2 mov.i >trash-10-i*2, pprm&i ppmp&i dat ptr&i+1, pmpof&i+ptr&i+1-pump&i pprm&i dat prime&i+3, prmof&i+prime&i+3-instr&i pstn&i dat jump&i+1, stnof&i+jump&i+1-bomb&i pump&i spl #1, >ptr&i add.f #istep+1, ptr&i ptr&i jmp pump&i-pmpof&i+impoff-istep-1, {200 ; C instr&i mov.i #1, istep prime&i spl #instr&i-prmof&i+impoff, >23 ; C mov.i instr&i, }prime&i jmn.b instr&i-prmof&i+stnof&i+1, instr&i-prmof&i+impoff+fuse bomb&i dat <5334, <2667 stone&i spl #stone&i+bstep&i+magic&i, {-1000 ; C mov.i bomb&i, }stone&i add.f #bstep&i-1, stone&i jump&i djn.f stone&i, <-30 ; C ROF FOR (MAXLENGTH-CURLINE)/3 mov #1, 1 mov #1, @1 spl #1, 1 ROF FOR MAXLENGTH-CURLINE dat #1, 1 ROF end Unless I'm mistaken, Calvin Loh has not published his JMP/ADD continuous launching design yet. Does it look like the above ? ______________________________________________________________________________ Extra Extra: Quickscanners by Robert Mcrae Core_Warrior_#4 carried a description of scanners. 0.66c or 0.80c is fast, but they're not _quick_! Lets look at the central loop of a very basic 0.66c scanner and ask what baggage can be removed. ; Code loosely based on simplified Core_Warrior_#4 scanner inc add.f step, scan ; nudge scan along scan sne.i 100, 112 ; scan djn.b inc, #1000 ; repeat 1000 times attack step dat 24, 24 The main loop takes 3 cycles to check 2 locations, hence the 0.66c figure. INC nudges the locations which are compared by SEQ instruction, DJN is needed to jump back to INC -- this looks like about as fast as we can get. But... Quickscanners Use INLINE CODING. The essential instruction to the above code is the comparison SNE. If we "unwrap" the loop into a long list of SNEs with no ADDs (since we hard-code the addresses to be scanned) and no DJNs (because we are not looping) then the comparison speed hits 2c -- every (executed) instruction is a SNE comparing _2_ locations. The result might look like this: start sne.i start+100, start+112 mov.ab #100, target sne.i start+124, start+136 mov.ab #124, target sne.i start+148, start+160 mov.ab #148, target sne.i start+172, start+184 mov.ab #172, target sne.... etc where target is used by the attack code as a pointer to the locations which have failed the SNE test. These may be attacked by any method such as SPL carpet, incendiary etc, but before considering attacks, ask whether the above code gains more than it loses compared to the scanner we derived it from: Good We have scanned 8 locations in just 4 cycles (given no hits). Bad The code to scan 8 locations fills 8 locations, so we are very vulnerable to bombers and scanners. We don't know where we've hit till the end of the inline sequence. A maximum-length warrior (100 instruction) can only scan 100 locations, or 1.3% of core. What do we do then? These features make Quickscans rather specialised tools. They are always (AFAIK) used as the _first_ stage of a composite warrior. Scanning less than 100 locations they cannot guarantee to hit anything, so some fallback strategy is needed -- scanner, bomber, whatever -- to handle the warriors they miss. If they hit, you should win. If they miss, you've just lost a few tens of cycles. Since they are run once through and then discarded, the vulnerability to bombers is ameliorated. It is a good exercise to calculate how likely a c=0.33 bomber is to kill a Quickscanner (say) 80 words long. (No, I don't know either, but I'd like to :) Quickscanners will be scanning early in the battle, certainly in the first 100 cycles, before many bombs have been thrown or replicators sprouted. Anything they detect is quite likely to be the enemy warrior code or a decoy close to it. This means they can afford to invest a _lot_ of effort on damaging that area of core. This completes the outline and philosophy of Quickscanners (didn't take long:), so now onto practical tips. Actually, since asking the right kind of question is more useful than reading a recipe, most of the work is up to you... Where to Scan? You occupy 100 cells, and the enemy is at least 100 away. That gives you 7700 to examine; why not space them evenly? Where should the end points be? What Order to Scan? If you do enough scans so that the spacing between locations is less than 100, here is a minor gain to scanning 1st, 3rd, 5th .. n-1th before you do 2nd, 4th .. nth. To see why, imagine your target is 100 cells long. Once you have scanned the 3rd location and found it empty, you have eliminated _some_ of the possible positions of the enemy which would give rise to a hit in the 2nd and 4th locations. This makes them worse bets than other locations, so leave them till later. (How big is the gain here? Is there any cost?) Are There Other Forms of QS? Several. The most interesting makes somewhat more efficient use of space by a sequence: SNE.i start+150, start+250 SEQ.i start+350, start+450 MOV.ab #150, Target ... Speed is still 2c, but this method packs 4 comparisons into 3 locations at the cost of requiring more work in decoding exactly where the hit occurred. This method was used in Pyramid and Thermite, which aim to win via their thorough QS, but Paul Klein's recently-published Die Hard used the simpler SNE/MOV scheme for maximum speed in decoding. He was just aiming to hit often enough to do damage with his brainwash, so packing density came second to decoding speed. Randy Graham came up with a scheme intermediate between a QS and a scanner, in which a long block of DAT pointers were used. This scans at "only" c=1, but has benefits in robustness (why?) and packing. SNE.i @ListTop, *ListTop DJN.f -1, -1 List DAT #7750, #7850 ... ListTop DAT #150, #250 [BTW I should credit the rest of the article too. Most of the things I know about Quickscanners came from experimenting with Michael Constant's Sauron-T, which is in the 1993 competition archive. Pyramid, a later QS of Michael's, is an excellent basis for experiment because it is fully parameterised. Apologies for any missed names, mistakes, misrepresentations or misrecollections.] How Should I Attack? Big topic, vital to any warrior so I'm going to digress. Any attack has to pay off being deadly against being quick to deliver. Classic bombers go for fast delivery, but typically of a single <, DAT or SPL. Scanners only spend time attacking plausible targets, by ignoring blank areas, so when they find something they can afford to take more time and deliver bigger, nastier bombs -- SPL carpets, incendiaries etc. Right at the end of the quick-to-nasty spectrum come Quickscanners. These will usually only find one target, but it is very high quality, meaning that there is a good chance that the enemy has a substantial fraction of his processes working near to the scanned location. We should invest substantial time flattening the whole area. I've seen various schemes for this. I like launching vampiric JMP instructions which suck enemy processes into a prepared SPL pit. Multiple incendiaries could do the trick, and so could SPL carpets, though this gets slow if you want to carpet a large area. How large Should the Area Be? Well... not more than +-100 cells from the location scanned. (Why?) This decision interacts with the speed of the method of bombing you use. We _hope_ we have clobbered the opponents code before he can boot away, but we cannot assume it. Another salutary calculation is just how fast we have to be; big imps are easy meat (you should probably make that "extinct" meat) but a bomber can boot in 20 cycles and leave you pasting his decoy. If he has booted away, we can't waste too long bombing air before we fall back on our second strategy... +-50 cells is probably as long as is needed, and you certainly hit diminishing returns if you bomb more than every 4th cell. Using a 0.33c bomber and hitting every 6th cell takes about 50 cycles to complete. Die Hard hit a smaller range, every 8th cell, with a 0.4c bomber for 20 cycles or so. The best solution here, as usual, is to experiment. If you can get hold of likely opponents and work out how quickly they boot, this will help guide the choices. Thermite [Editor note: Thermite has been posted in Core warrior # 5; you can find it at Planar's home page - http://pauillac.inria.fr/~doligez/corewar/rc/Thermite.txt] I hope that these notes have given sufficient background so that the choices made in Thermite (Core_Warrior_#5) make sense. These notes go into a little more detail than the in-code comments but see #5 for the source. Most importantly, I use FOR/ROF rather than typing the addresses! Pyramid goes further, with adjustable parameters for number of scans etc. I use the SNE/SEQ form of scan to get the scan spacing down to 81 cells. When I have a hit, I scan through the 4 alternatives in a short loop. (Spot the weakness here; Randy pointed out a wasted cycle or two, but I don't remember where...) I launch an SPL bomb straight at my hit, before starting the main vampiric bomb run. I believe this reduces the chance of the enemy booting away before the bomb-run gets back to the original hit (but why not check?). The occasional JMN instructions check whether a hit has been made. If it has, I jump direct to the bombing routine saving a few wasted scanning cycles. The gain is not great, because each JMN test is guaranteed to cost one cycle but has a relatively small chance of saving any. (For _real_ enthusiasts, what is the spacing of the JMNs which optimises expected speed of hits? I think there are more JMNs near the beginning...) I bite at 0.33c, from about 50 after the hit to 100 before. The asymmetry arose because I was keen to bomb "near" the original hit quickly, but didn't mind spending a few extra cycles "making sure" on the far end. Does the asymmetry pay? What is the chance that I miss a kill by not biting +50 to +100? What is the (weak) reason for bombing from -81 to -100? I use fangs which do an indirect jump via a location well away from the trap. This is meant to help against indirect-bombing silks, because I have only 1 pointer to the trap which is shared by all the bites. My pit concentrates on splitting as fast as possible, but why not add a brainwash? Beppe pointed out that if you plan to use the QS with a paper, the pit should commit suicide eventually because the paper cannot guarantee to kill it. Perhaps use a DJN trail wrapping round core? Or should the pit work as a bomber? How many points do I lose not booting? There are lots of options to explore. It is easy to add a QS to most conventional warriors and the performance gain can be substantial. If you already have a reasonable warrior less than 70 cycles long, why not trade in the decoy for a QS, which will work for its living..? ______________________________________________________________________________ Questions? Concerns? Comments? Complaints? Mail them to: Beppe Bezzi or Myer R Bremer 