December 2011 - Pharo-dev - lists.pharo.org

Re: [Pharo-project] Two complement smallInteger question

by StÃ©phane Ducasse

I read somewhere that in C short int range value are -32767 to +32767 http://www.ericgiguere.com/articles/ansi-c-summary.html And I was wondering why it does not follow the $-1 * 2^{N-1}\ to\ 2^{N-1}-1$ range encoding Stef On Dec 23, 2011, at 11:35 AM, StÃ©phane Ducasse wrote: > Hi > > I'm doing a pass on the two complement chapter and small integer implementation and I wanted to check the SmallInteger>>primitiveAdd see below: > > stackIntegerValue extracts from a smalltalk integer the 31 encoding number bit. I imagine that this is correct. > > sqInt > stackIntegerValue(sqInt offset) { > DECL_MAYBE_SQ_GLOBAL_STRUCT > sqInt integerPointer; > integerPointer = longAt(GIV(stackPointer) + (offset * BytesPerWord)); > /* begin checkedIntegerValueOf: */ > if ((integerPointer & 1)) { > return (integerPointer >> 1); > } > else { > /* begin primitiveFail */ > if (GIV(primFailCode) == 0) { > GIV(primFailCode) = 1; > } > return 0; > } > } > > Now I have three questions: > - is two complement used to manage small integers at VM level? > I saw digitAdd on Integer and it deals with large integer. > > - integerResult = (stackIntegerValue(1)) + (stackIntegerValue(0)); > performs the real add. I imagine that it comes from plain C. Now does anybody has an idea > where I could find the definition of such + procedure? > In ANSI C > > - from the books, performing 54 - 5 is equivalent to adding the two complement > i.e. 54 + 5' (two complement) > this work well for 54 - 5 correct results and we can follow it looking at binary operations: > > (2r110110 - 2r101) bitString > --> '0000000000000000000000000110001' > (2r110110 bitString) > --> '0000000000000000000000000110110' > 2r101 bitString > --> '0000000000000000000000000000101' > 2r101 negated bitString > --> '1111111111111111111111111111011' > > Now doing 5 - 15 does not (or I miss something ilke always subtracting the smaller one and taking the two complement of the smallerâ¦) > so does anybody has the answer on how to perform 5 - 15 ? > > > > > > static void > primitiveAdd(void) { > DECL_MAYBE_SQ_GLOBAL_STRUCT > sqInt integerResult; > char *sp; > > /* begin pop2AndPushIntegerIfOK: */ > integerResult = (stackIntegerValue(1)) + (stackIntegerValue(0)); > if (GIV(primFailCode) == 0) { > if ((integerResult ^ (integerResult << 1)) >= 0) { > /* begin pop:thenPush: */ > longAtput(sp = GIV(stackPointer) + ((2 - 1) * BytesPerWord), ((integerResult << 1) | 1)); > GIV(stackPointer) = sp; > } > else { > /* begin success: */ > if (!(0)) { > if (GIV(primFailCode) == 0) { > > /* Don't overwrite an error code that has already been set. */ > > GIV(primFailCode) = 1; > } > } > } > } > } > > > Stef

Dec. 23, 2011

[Pharo-project] Two complement smallInteger question

by StÃ©phane Ducasse

Hi I'm doing a pass on the two complement chapter and small integer implementation and I wanted to check the SmallInteger>>primitiveAdd see below: stackIntegerValue extracts from a smalltalk integer the 31 encoding number bit. I imagine that this is correct. sqInt stackIntegerValue(sqInt offset) { DECL_MAYBE_SQ_GLOBAL_STRUCT sqInt integerPointer; integerPointer = longAt(GIV(stackPointer) + (offset * BytesPerWord)); /* begin checkedIntegerValueOf: */ if ((integerPointer & 1)) { return (integerPointer >> 1); } else { /* begin primitiveFail */ if (GIV(primFailCode) == 0) { GIV(primFailCode) = 1; } return 0; } } Now I have three questions: - is two complement used to manage small integers at VM level? I saw digitAdd on Integer and it deals with large integer. - integerResult = (stackIntegerValue(1)) + (stackIntegerValue(0)); performs the real add. I imagine that it comes from plain C. Now does anybody has an idea where I could find the definition of such + procedure? In ANSI C - from the books, performing 54 - 5 is equivalent to adding the two complement i.e. 54 + 5' (two complement) this work well for 54 - 5 correct results and we can follow it looking at binary operations: (2r110110 - 2r101) bitString --> '0000000000000000000000000110001' (2r110110 bitString) --> '0000000000000000000000000110110' 2r101 bitString --> '0000000000000000000000000000101' 2r101 negated bitString --> '1111111111111111111111111111011' Now doing 5 - 15 does not (or I miss something ilke always subtracting the smaller one and taking the two complement of the smallerâ¦) so does anybody has the answer on how to perform 5 - 15 ? static void primitiveAdd(void) { DECL_MAYBE_SQ_GLOBAL_STRUCT sqInt integerResult; char *sp; /* begin pop2AndPushIntegerIfOK: */ integerResult = (stackIntegerValue(1)) + (stackIntegerValue(0)); if (GIV(primFailCode) == 0) { if ((integerResult ^ (integerResult << 1)) >= 0) { /* begin pop:thenPush: */ longAtput(sp = GIV(stackPointer) + ((2 - 1) * BytesPerWord), ((integerResult << 1) | 1)); GIV(stackPointer) = sp; } else { /* begin success: */ if (!(0)) { if (GIV(primFailCode) == 0) { /* Don't overwrite an error code that has already been set. */ GIV(primFailCode) = 1; } } } } } Stef

Dec. 23, 2011

Re: [Pharo-project] Guess who is down?

by Fabrizio Perin

it will be up in minutes 2011/12/23 Luc Fabresse <luc.fabresse(a)gmail.com> > > 2011/12/14 Bernat Romagosa <tibabenfortlapalanca(a)gmail.com> > >> Could someone push that reset button again please? :) > > > up. > thx to whom will do it ;-) > > Luc > > >> >> >> -- >> Bernat Romagosa. >> > >

Dec. 23, 2011

Re: [Pharo-project] Guess who is down?

by Luc Fabresse

2011/12/14 Bernat Romagosa <tibabenfortlapalanca(a)gmail.com> > Could someone push that reset button again please? :) up. thx to whom will do it ;-) Luc > > > -- > Bernat Romagosa. >

Dec. 23, 2011

Re: [Pharo-project] gtinspector

by Tudor Girba

Hi, On 22 Dec 2011, at 10:05, Mariano Martinez Peck wrote: > > > On Thu, Dec 22, 2011 at 12:28 AM, Tudor Girba <tudor(a)tudorgirba.com> wrote: > Hi, > > On 21 Dec 2011, at 12:15, Mariano Martinez Peck wrote: > > > > > > > On Wed, Dec 21, 2011 at 9:01 AM, Tudor Girba <tudor(a)tudorgirba.com> wrote: > > Hi, > > > > Just out of curiosity: Does any of you use the GTInspector? > > > > I used to use it for my images. And it was pretty nice. Problem was the amount of dependencies it had, the time it took me to install it, and moreover, that since it depends on several dependencies it was always complicated to successfully install it. Apart from that, I really like it. > > Thanks. What do you mean by complicated to install it? > > That each time I tried I found a problem. I don't remember exactly now. First, it was a problem with RB (which was used from Grease I think) which was not even loading in the image. Then it was the Keymappings which was broken and annoying ;) These are all fixed now. Actually, these issues got fixed within max 1 day from when they got detected. The Glamorous Toolkit is used in all Moose builds, so there is a high incentive for us to fix those problems. > I like the GTInspector and I like Glamour and all its related tools, but I always wondered the same: isn't there a way to use Glamour just for the development part? What I mean is that in this example of the GTInspector, it would be nice if you can generate from Glamour a plain standalone Morphic UI that we can just load. Say I have developed using glamour and all its nice features and then as an output I get a running morphic. Then of course, there will be people who will always want the glamour version because they change the code or whatever. Anyway, does it sound crazy to have a way to "deploy" Glamour? I do not see how it would be possible to do that. Glamour is a runtime engine, and as a consequence it is required to run the browser :). Just to clarify: Most of the Glamour dependencies that are loaded by default are due to extra support like EyeSee, Mondrian and Magritte. If people do not want these, they do not have to be loaded. For example, to load just the basic Glamour, you can load it like: (ConfigurationOfGlamour project version: 'default') load: {'Core'. 'Morphic'} Cheers, Doru > Where did you encounter problems? > > Cheers, > Doru > > -- > www.tudorgirba.com > > "Speaking louder won't make the point worthier." > > > > > > -- > Mariano > http://marianopeck.wordpress.com > -- www.tudorgirba.com "Don't give to get. Just give."

Dec. 23, 2011

Re: [Pharo-project] gtinspector

by Tudor Girba

Hi, Yes. It will load: Glamour (which loads Mondrian, EyeSee, Magritte and some of its unnecessary dependencies :)), and the Glamorous Toolkit itself which also depends on RPackage so that one will be loaded as well. Cheers, Doru On 23 Dec 2011, at 00:30, Sean P. DeNigris wrote: > > Tudor Girba-2 wrote >> >> You can load it in a Pharo 1.3 image by... >> > > Is everything loaded by that command necessary for Glamour and its toolkit? > e.g. Mondrian, EyeSee, Magritte > > -- > View this message in context: http://forum.world.st/gtinspector-tp4220848p4226991.html > Sent from the Pharo Smalltalk mailing list archive at Nabble.com. > -- www.tudorgirba.com "Yesterday is a fact. Tomorrow is a possibility. Today is a challenge."

Dec. 23, 2011

Re: [Pharo-project] gtinspector

by Sean P. DeNigris

Tudor Girba-2 wrote > > You can load it in a Pharo 1.3 image by... > Is everything loaded by that command necessary for Glamour and its toolkit? e.g. Mondrian, EyeSee, Magritte -- View this message in context: http://forum.world.st/gtinspector-tp4220848p4226991.html Sent from the Pharo Smalltalk mailing list archive at Nabble.com.

Dec. 22, 2011

Re: [Pharo-project] COTDC

by StÃ©phane Ducasse

just continue On Dec 22, 2011, at 9:07 PM, Sean P. DeNigris wrote: > The last three classes got no responses. Do we not want to play anymore? > > -- > View this message in context: http://forum.world.st/COTDC-tp4226492p4226492.html > Sent from the Pharo Smalltalk mailing list archive at Nabble.com. >

Dec. 22, 2011

Re: [Pharo-project] IdentitySet but using #hash rather than #identityHash ?

by StÃ©phane Ducasse

I will :) Thanks mariano On Dec 22, 2011, at 9:11 PM, Mariano Martinez Peck wrote: > So...the fix for #pointsTo: and #instVarsInclude: is in inbox: > > http://code.google.com/p/pharo/issues/detail?id=5118 > > If anyone wants to take a look... > > Cheers > > On Tue, Dec 20, 2011 at 11:01 PM, Mariano Martinez Peck <marianopeck(a)gmail.com> wrote: > > > 2011/12/20 Levente Uzonyi <leves(a)elte.hu> > On Tue, 20 Dec 2011, Mariano Martinez Peck wrote: > > > Thanks Levente. Well, now all our tests and benchmarks pass like a charm > :) We will soon include it in the "trunk" of Fuel. Will them be available > in a repository for squeak? because if so, I can adapt ConfiguratioOfFuel > so that in Squeak it loads another collections. > > > The best would be to add the patch to Pharo, which fixes #pointsTo: and > adds #instVarsIncludes:. Then change the code to use #instVarsInclude: in > these collections. If that's all done, then this code should work in both > Pharo and Squeak. > > > Yes, I agree. But anyway, Fuel will load in previous versions of Pharo, > where such fix won't be integrated. So we will need to handle this. > > This can easily solved with a separate Metacello configuration. > > > Yes, I will do that. > > > > > > > > > So...from the benchmarks I can say that in large graphs the improve in > performance was 30% in serialization, and only use in one place the set > and > in another one the dictionary. > > > Great, hopefully the new primitive will increase this even more. :) > > > > Hopefully. Did you answer Eliot? he was asking what you needed... > > I did answer his private email about the primitive. > > > Ahh ok, excellent :) > > > > Ahh BTW, I found another small bug.. LargeIdentityDictionary sends > #keyNotFound but it is not implemented. Just adding: > > errorKeyNotFound: aKey > > KeyNotFound signalFor: aKey > > is enough. > > Go ahead. :) > > > Done > > > Levente > > > Cheers > > > > Levente > > > Thanks!!! > > > > > Levente > > > Cheers > > > > Levente > > > On Sun, Dec 18, 2011 at 7:17 PM, Mariano Martinez Peck < > > marianopeck(a)gmail.com> wrote: > > > > Now I noticed that SmallIntegers storing is really slow > > > > This is not entirely true. Every hash table can be made slow if > you > > know > how it's hash function works. Since in your example all numbers are > congruent to 1 modulo 4096 and the size of the array is also 4096, > therefore they will be mapped to the same slot (1). Try using > random > (or at > least more realistic) numbers in your test. If this is a real > problem, > then > it may be necessary to implement a new hash method, which uses the > primitive for general objects and does something else with > SmallIntegers > and that method shoul be used from these large collections. > > > I uploaded a new mcz to the FuelExperiments repository, which is > > unaffected by the identity hash differences between Pharo and Squeak > and > works better with SmallIntegers. It includes both the dictionary and > the > set and (in theory) has slightly better performance for > non-SmallInteger > objects. > > > Hi Levente. First let me say I really appreaciate your effort in > make > > it > work. It makes definitvly Fuel faster and it would make sense to > integrate > them also in Squeak and Pharo. > Now, I found another bug. To reproduce it: > > | dict | > dict := LargeIdentityDictionary new. > dict at: 16941057 put: 1035. > > Now, it seems 16941057 largeIdentityHash answers 4096 and the comment > of > #largeIdentityHash says ""Return an integer between 0 and 4095 based > on > all of my bits. Make sure that for nearby receivers the result will > not > be > nearby with high probability."" > > The thing is that LargeIdentityHashedCollection permuteHash: hash + 1 > answers 4096, and hence, when in #at:put: you do: > > at: key put: value > > | hash | > (keys at: (hash := key largeIdentityHash + 1)) > > then you get the out of bounds. > > Modyfing > > initialize > > | rng | > rng := Random seed: 664399324. > PermutationMap := (1 to: 4096) asArray shuffleBy: rng > > to 4095 make some tests to pass, but there are some other failing. > > I will try to continue to see if I find the error. > > Thanks! > > > Levente > > > > > > Levente > > > > numbers := OrderedCollection new. > > numbers add: 1. > numbers addAll: (1 to: 1 << 29 by: 1 << 14) asArray. > numbers addAll: ((1 to: 1 << 29 by: 1 << 14) asArray collect: > [:each > | > each negated] ). > > dict := LargeIdentityDictionary new. > [numbers do: [:each | > dict at: each put: dict size + 1. > ]. > ] timeToRun > -> 12657 > > > whereas with IdentityDictionary it is 37. I guess it could be > related > to > #identityHash or #basicIdentityHash. I tried in Squeak 4.3 and it > is > also > also there. > I will try to take a look into it during the next week. > > Thanks in advance > > > > Nicolas > > > > Thanks for any idea. > > > > > On Sat, Dec 17, 2011 at 1:50 PM, StÃ©phane Ducasse > <stephane.ducasse(a)inria.fr> wrote: > > > > On Dec 16, 2011, at 3:28 PM, Levente Uzonyi wrote: > > Cool. One more thing: in Squeak the method using primitive > 132 > > > directly > > > > was renamed to #instVarsInclude:, so now #pointsTo: works as > > > > > expected. If > > > > > this was also added to Pharo, then the #pointsTo: sends > should > > be > > > > changed to > > > > > #instVarsInclude:, otherwise Array can be reported as > included > > even > > > > if it > > > > > wasn't added. > > > > I'll upload my LargeIdentityDictionary implementation to the > same > > > > place > > > > this evening, since it's still 2-3 factor faster than other > > > > > solutionts and > > > > > there seem to be demand for it. > > > > > > Levente > > > "in Squeak the method using primitive 132 directly was > renamed > to > > #instVarsInclude:, so now #pointsTo: works as expected." > > > I do not get the following. Indeed pointTo: looks like > > instVarsInclude: > now I do not understand the rest of your paragraph. > > Stef > > > > > > -- > Mariano > http://marianopeck.wordpress.********com<http://marianopeck.** > wordpress.com <http://marianopeck.wordpress.****com< > http://marianopeck.**wordpress.com<http://marianopeck.wordpress.com> > > > > > > > > > -- > > Mariano > http://marianopeck.wordpress.********com < > http://marianopeck.wordpress.****** > com <http://marianopeck.wordpress.****com<http://marianopeck.** > wordpress.com <http://marianopeck.wordpress.com>> > > > > > > > -- > Mariano > http://marianopeck.wordpress.******com < > http://marianopeck.wordpress.**** > com <http://marianopeck.wordpress.**com<http://marianopeck.wordpress.com> > > > > > > -- > Mariano > http://marianopeck.wordpress.******com <http://marianopeck.wordpress. > > **** > com <http://marianopeck.wordpress.**com<http://marianopeck.wordpress.com> > > > > > > -- > Mariano > http://marianopeck.wordpress.****com <http://marianopeck.wordpress.** > com <http://marianopeck.wordpress.com>> > > > > > -- > Mariano > http://marianopeck.wordpress.**com <http://marianopeck.wordpress.com> > > > > > -- > Mariano > http://marianopeck.wordpress.com > > > > -- > Mariano > http://marianopeck.wordpress.com > > > > > -- > Mariano > http://marianopeck.wordpress.com >

Dec. 22, 2011

Re: [Pharo-project] [OT] Pharo and children

by StÃ©phane Ducasse

have a look at "cs unplugged" there is french version. Stef On Dec 22, 2011, at 6:53 PM, laurent laffont wrote: > Hi, > > my son will soon have 7 years old and starts to show interest in how all these things move on screen. I wonder what are your cool ways to teach programming with instant fun for kids. > > Any experience ? > > Cheers, > > Laurent Laffont - @lolgzs > > Blog: http://magaloma.blogspot.com/ > Developer group: http://www.cara74.org > Pharo Smalltalk Screencasts: http://www.pharocasts.com/ > Pharo web deployment: http://www.alpha.smallharbour.org

Dec. 22, 2011