Can you write code directly in CIL ???

[Willy Denoyette [MVP]]

Re: Can you write code directly in CIL ???


"Peter Olcott" <olcott@att.net > wrote in message
news:IEbsf.3796 5$QW2.18916@duk eread08...[color=blue]
>
> "Abubakar" <abubakarm@gmai l.com> wrote in message
> news:%23tiR4prC GHA.3820@TK2MSF TNGP12.phx.gbl. ..[color=green]
>> Hi,[color=darkred]
>>> Cab you write code directly in the Common Intermediate language? I need
>>> to
>>> optimize a critical real-time function.[/color]
>>
>> ofcourse you can, by now you may even have done it. Just write few *.il
>> lines and pass it to ilasm (that comes with the sdk) and you'll get the
>> managed binary.
>>
>> although Nicholas tried explaning. I have just few things to add.
>>
>> 1- If you look at the shared source implementation of .net, ie, SSCLI
>> (aka
>> ROTOR), you wont find a single *.il file that microsoft devs had to write
>> in
>> order to acheive better performance. The max they did to write fast code
>> as
>> a .net code was to write the unsafe C# code (which uses pointers). Beyond
>> that, places that needed to get maximum efficiency like JIT, they used a
>> pure c++ code and in very few places, x86 assembly code was used. I think
>> if
>> those developers could acheive anything significant by writing il
>> directly,
>> they would have done that.[/color]
> What I had in mind was to write the best possible code in C++ and have the
> best compiler translate this into assembly language. The best compiler so
> far seems to be Visual C++ 6.0. Some of the optimizations in 7.0 are
> disabled, in particular function inlining. Then I was going to hand tweak
> this generated assembly language. Then as a final step I was going to
> translate this into CIL.
>[color=green]
>> 2- C# compiler is as clever in generating msil as anyone can possibly
>> get. I[/color]
> False assumption when one examines the benchmarks of managed C++ against
> managed C#, Managed C++ does significantly better in at least some cases.
>[/color]

Not sure where you get this from? Did you actually run such benchmarks?
I did run many benchmarks, since v1.0 comparing both C# and Managed C++ (and
C++/CLI) and I never saw a delta (yes, for some C# is the winner) larger
than 5%, using v2 they are even smaller.



Willy.

[Nicholas Paldino [.NET/C# MVP]]

Re: Can you write code directly in CIL ???

That's laughable, honestly, to think that 100 lines of C++ code will
translate into 100 lines of C# code. It's a pretty blanket statement which
can be shot down in a number of different ways.

Why not post the C++ code? Are you sure that all of the facilities that
are available to you in that C++ code are available in .NET? Do you have to
call other APIs? Are you sure there are all managed equivalents?

I think it's time to either post the code, or let the thread die.


--
- Nicholas Paldino [.NET/C# MVP]
- mvp@spam.guard. caspershouse.co m

"Peter Olcott" <olcott@att.net > wrote in message
news:9ybsf.3795 1$QW2.24780@duk eread08...[color=blue]
>
> "Pohihihi" <noemail@hotmai l.com> wrote in message
> news:e5TKP%23qC GHA.516@TK2MSFT NGP15.phx.gbl.. .[color=green]
>> Your benchmarking on perfomance is bit off posting to posting. If it is
>> 100 lines of code in asm then surely it will be performing better but how
>> many lines of .NET conversion of it. But if you are saying 100 lines of
>> code in .Net then I wonder how many lines of instruction code your .net
>> code is creating to execute it several million times in a given second or
>> 10 of a second or which ever benchmark is correct.[/color]
> It is currently writtten is Visual C++ 6.0 I tried compiling it with
> Visual C++ 7.0, but this compiler produces poorer code quality by failing
> to inline functions. My discussion of .NET is hypothetical. I am going to
> translate the unmanaged C++ into managed C#. It is about 100 lines of
> unmanaged C++ now. This will translate into about 100 lines of managed C#.
>[color=green]
>>
>> Well anyways, seems like you know the ground you are playing on so for
>> the answer for your original question, yes you can write the whole
>> program in IL. I will be interested in knowing how you optimized it.
>>
>>
>>
>>
>> "Peter Olcott" <olcott@att.net > wrote in message
>> news:4S4sf.3793 7$QW2.7702@duke read08...[color=darkred]
>>> Not only will it run several million times every second, but, it will
>>> constantly access all of its memory. Can I write a .NET component using
>>> purely unmanaged code? That would seem to be a contradiction in terms.
>>>
>>> "Pohihihi" <noemail@hotmai l.com> wrote in message
>>> news:e6$JcnqCGH A.916@TK2MSFTNG P10.phx.gbl...
>>>> IMHO and according to the following link GC is way better than
>>>> traditional memory mgmt. If method is running many million times a
>>>> second (really??) then GC will keep it. But as Nicholas said, running
>>>> of GC is a overhead and it is in control of CLR. Just because your code
>>>> knows how much memory it needs it really do not mean that it will
>>>> always have that in hand. Again GC is god here. If you want control of
>>>> your code and how it behaves than leave managed environment and go for
>>>> traditional C++/C/ASM route, or as suggested Interop.
>>>>
>>>> http://msdn.microsoft.com/library/de...tperftechs.asp
>>>> section -->
>>>> "Myth: Garbage Colloction Is Always Slower Than Doing It by Hand"
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> "Nicholas Paldino [.NET/C# MVP]" <mvp@spam.guard .caspershouse.c om>
>>>> wrote in message news:%23YB$FaqC GHA.3820@TK2MSF TNGP12.phx.gbl. ..
>>>>> Peter,
>>>>>
>>>>> You are missing the point completely. If you implement your code
>>>>> as managed code, even in IL, you can't stop a GC no matter what. Your
>>>>> thread is going to be pre-empted (in most situations, except if you
>>>>> have the GC running on a separate thread) and it WILL stop and it WILL
>>>>> affect your performance when it happens.
>>>>>
>>>>> Just because your code knows how much memory it needs doesn't mean
>>>>> that you can pre-empt a GC. If it happens, it's going to happen, and
>>>>> there is nothing you can do about it. Your 100-line function isn't
>>>>> going to be able to stop it, and the CLR isn't going to care what your
>>>>> function is doing.
>>>>>
>>>>> You can't just pretend its not going to happen. It does, and it
>>>>> will, and you can't stop it. This isn't a choice you have if you are
>>>>> running managed code, whether you do it in IL or not.
>>>>>
>>>>> This is what it means to have ^managed^ code. The CLR is going to
>>>>> provide a good number of services, but you are going to have to pay
>>>>> for them, and should be aware of how they impact your code.
>>>>>
>>>>> This is why I recommended that you use interop with your unmanaged
>>>>> code. You will have your performance requirements fufilled, and not
>>>>> have to worry about doing something that will ultimately be
>>>>> self-defeating.
>>>>>
>>>>> --
>>>>> - Nicholas Paldino [.NET/C# MVP]
>>>>> - mvp@spam.guard. caspershouse.co m
>>>>>
>>>>> "Peter Olcott" <olcott@att.net > wrote in message
>>>>> news:GV3sf.3792 7$QW2.2410@duke read08...
>>>>>>
>>>>>> "Nicholas Paldino [.NET/C# MVP]" <mvp@spam.guard .caspershouse.c om>
>>>>>> wrote in message news:uvvaatpCGH A.4004@tk2msftn gp13.phx.gbl...
>>>>>>> Peter,
>>>>>>>
>>>>>>> You don't understand a fundamental concept to .NET and CIL. Yes,
>>>>>>> there are compilers that will perform optimization of IL to a
>>>>>>> certain degree.
>>>>>>>
>>>>>>> However, when the managed code is run, the CLR will take the CIL
>>>>>>> and then compile it into native code. At this point in time, it is
>>>>>>> free to optimize, or not optimize, or mangle your code in any way
>>>>>>> you want when making the transition from CIL to native code.
>>>>>>>
>>>>>>> When you are dealing with assembly language in general, you have
>>>>>>> complete control of what is going on, memory allocation,
>>>>>>> deallocation, execution, etc, etc. With the CLR, this is taken out
>>>>>>> of your hands to a degree.
>>>>>>
>>>>>> I don't care about these things they are not effecting my
>>>>>> performance. What is effecting my performance are things such as the
>>>>>> compiler failing to inline my functions code, and unnecessary
>>>>>> overhead in the translation of a switch statement. My function will
>>>>>> be always executed several million times every second. It must run
>>>>>> concurrently with other applications.
>>>>>>
>>>>>>>
>>>>>>> For example, have you considered, what happens when a Garbage
>>>>>>> Collection (GC) occurs while your function is running? If it is in
>>>>>>> complete managed code, then there is nothing that you can do about
>>>>>>> it, and your function will resume running when the GC is complete.
>>>>>>> Depending on what is happening on the machine at the time, combined
>>>>>>> with what your program is doing, etc, etc, it is very feasible that
>>>>>>> your code will take more than 1/10th of a second.
>>>>>> My code knows exactly how much memory it needs at load time. It needs
>>>>>> all of this memory the whole time that it executes. It would make no
>>>>>> sense to have any garbage collection of my code's memory in this
>>>>>> case. I want my code to be implemented as a .ET component.
>>>>>>
>>>>>>>
>>>>>>> Just because it looks like assembly language, don't assume that
>>>>>>> CIL is assembly language. There are some very different things
>>>>>>> going on under the hood.
>>>>>>>
>>>>>>> --
>>>>>>> - Nicholas Paldino [.NET/C# MVP]
>>>>>>> - mvp@spam.guard. caspershouse.co m
>>>>>>>
>>>>>>> "Peter Olcott" <olcott@att.net > wrote in message
>>>>>>> news:xj2sf.3790 6$QW2.34052@duk eread08...
>>>>>>>>I want to be able to stick with purely managed code, if possible. I
>>>>>>>>just need this 100 line function to run as fast as if it was hand
>>>>>>>>tweak ed assembly language. I have examined CIL, for the most part it
>>>>>>>>is essentially assembly language. From what I understand any
>>>>>>>>optimiz ations take place before the CIL is generated. When I
>>>>>>>>designe d this system (in 1998) I had hand tweaked assembly language
>>>>>>>>in mind for this crucial function all along.
>>>>>>>>
>>>>>>>> "Nicholas Paldino [.NET/C# MVP]" <mvp@spam.guard .caspershouse.c om>
>>>>>>>> wrote in message news:%23RjK3$oC GHA.2040@TK2MSF TNGP14.phx.gbl. ..
>>>>>>>>> Peter,
>>>>>>>>>
>>>>>>>>> Not at all. When the CLR gets a hold of the JIT, it is free to
>>>>>>>>> perform any optimizations it deems necessary, and that might not
>>>>>>>>> necessarily be in line with what you are expecting.
>>>>>>>>>
>>>>>>>>> My recommendation would be to use Managed C++ to create a
>>>>>>>>> wrapper to your unmanaged code which uses It Just Works (IJW,
>>>>>>>>> seriously). You should get a managed interface, and the best
>>>>>>>>> possible performance (for this specific situation, not all
>>>>>>>>> situations) between managed an unmanaged code.
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> --
>>>>>>>>> - Nicholas Paldino [.NET/C# MVP]
>>>>>>>>> - mvp@spam.guard. caspershouse.co m
>>>>>>>>>
>>>>>>>>> "Peter Olcott" <olcott@att.net > wrote in message
>>>>>>>>> news:_51sf.3789 8$QW2.37853@duk eread08...
>>>>>>>>>>I need the best possible execution speed. I have found that there
>>>>>>>>>>is a large difference in the quality of the code generated by the
>>>>>>>>>>vario us compilers. I have 16,000 hours of development time in my
>>>>>>>>>>curre nt project. There is a 100 line function that must take no
>>>>>>>>>>longe r than 1/10 second to execute. I can just barely achieve this
>>>>>>>>>>wit h MSVC++ 6.0. MSVC++ 7.0 has had some of its optimizations
>>>>>>>>>>disab led. I eventually will need to port this to C# .NET. This is
>>>>>>>>>>a case where hand tweaked assembly language would be appropriate.
>>>>>>>>>>I figured that hand tweaked CIL would be the .NET equivalent of
>>>>>>>>>>han d tweaked assembly language.
>>>>>>>>>>
>>>>>>>>>> "Nicholas Paldino [.NET/C# MVP]"
>>>>>>>>>> <mvp@spam.guard .caspershouse.c om> wrote in message
>>>>>>>>>> news:OCvd7unCGH A.2644@TK2MSFTN GP09.phx.gbl...
>>>>>>>>>>> Peter,
>>>>>>>>>>>
>>>>>>>>>>> You can write it, but you would have to create a module with
>>>>>>>>>>> IL, and then compile that into your assembly (or just write the
>>>>>>>>>>> whole assembly).
>>>>>>>>>>>
>>>>>>>>>>> Also, what optimizations do you think you can make?
>>>>>>>>>>> Ultimately, you suffer from the fact that Windows is not a
>>>>>>>>>>> real-time OS, and nothing you can do will change that. On top
>>>>>>>>>>> of that, the JIT is what's going to optimize your code again
>>>>>>>>>>> after you try to, so you might actually end up hurting yourself
>>>>>>>>>>> more than helping yourself.
>>>>>>>>>>>
>>>>>>>>>>> If you post the code you are trying to optimize, we can try
>>>>>>>>>>> and tell you where you might make some improvements, but dipping
>>>>>>>>>>> down to the IL level is most likely not going to help you much.
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> --
>>>>>>>>>>> - Nicholas Paldino [.NET/C# MVP]
>>>>>>>>>>> - mvp@spam.guard. caspershouse.co m
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> "Peter Olcott" <olcott@att.net > wrote in message
>>>>>>>>>>> news:7t%rf.3788 7$QW2.9998@duke read08...
>>>>>>>>>>>> Cab you write code directly in the Common Intermediate
>>>>>>>>>>>> language? I need to optimize a critical real-time function.
>>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>
>>>>>>
>>>>>
>>>>>
>>>>
>>>>
>>>
>>>[/color]
>>
>>[/color]
>
>[/color]

[Nicholas Paldino [.NET/C# MVP]]

Re: Can you write code directly in CIL ???

I will second that the C++ compiler is better at optimizing IL output
than the C# compiler. However, as Willy stated, it will not always produce
verifiable code... I believe the article you were looking for is in MSDN
magazine.

But as a general statement, the C++ compiler generally has the best
optimizations (and for unmanaged code, with the new profile-guided
optimization, it's even cooler).

--
- Nicholas Paldino [.NET/C# MVP]
- mvp@spam.guard. caspershouse.co m

"Jon Skeet [C# MVP]" <skeet@pobox.co m> wrote in message
news:MPG.1e1b36 c8c5e95e598cbe2 @msnews.microso ft.com...[color=blue]
> Abubakar <abubakarm@gmai l.com> wrote:[color=green][color=darkred]
>> > It's a shame I can't find the newsgroup thread I'm thinking about - I
>> > could give it a try with C# 2.0...[/color]
>>
>> btw what search engine are you using? It maybe socking for some people
>> but
>> few days back I was searching some thread and for the same keywords
>> google
>> could not find the post but msn search (search.msn.com ) did :)[/color]
>
> groups.google.c om, which is what I always use for newsgroup posts.
> (Note: not just "web google".) It'll be there somewhere, but I just
> can't find it at the moment...
>
> --
> Jon Skeet - <skeet@pobox.co m>
> http://www.pobox.com/~skeet Blog: http://www.msmvps.com/jon.skeet
> If replying to the group, please do not mail me too[/color]

[Jon Skeet [C# MVP]]

Re: Can you write code directly in CIL ???

Nicholas Paldino [.NET/C# MVP] <mvp@spam.guard .caspershouse.c om> wrote:[color=blue]
> I will second that the C++ compiler is better at optimizing IL output
> than the C# compiler. However, as Willy stated, it will not always produce
> verifiable code... I believe the article you were looking for is in MSDN
> magazine.[/color]

No, the article was definitely someone posting in this group saying, "I
want to be able to embed IL in my C# code, here's why." He then
produced some better IL (which I suspect *was* verifiable) which the C#
compiler "could" have produced from the source C# (i.e. the behaviour
was identical).

I'm sure this will improve over time, but to be honest it's usually the
JIT that has more to do with optimisation IMO.
[color=blue]
> But as a general statement, the C++ compiler generally has the best
> optimizations (and for unmanaged code, with the new profile-guided
> optimization, it's even cooler).[/color]

Right.

--
Jon Skeet - <skeet@pobox.co m>
http://www.pobox.com/~skeet Blog: http://www.msmvps.com/jon.skeet
If replying to the group, please do not mail me too

[Peter Olcott]

Re: Can you write code directly in CIL ???


"Willy Denoyette [MVP]" <willy.denoyett e@telenet.be> wrote in message
news:euZ6UfvCGH A.1028@TK2MSFTN GP11.phx.gbl...[color=blue]
>
> "Peter Olcott" <olcott@att.net > wrote in message
> news:YObsf.3796 8$QW2.21788@duk eread08...[color=green]
>>
>> "Willy Denoyette [MVP]" <willy.denoyett e@telenet.be> wrote in message
>> news:uy36QvtCGH A.3920@tk2msftn gp13.phx.gbl...[color=darkred]
>>>
>>> "Andreas Mueller" <me@privacy.net > wrote in message
>>> news:41cjpeF1cm 3s3U1@individua l.net...
>>>> Peter Olcott wrote:
>>>>
>>>>> "Nicholas Paldino [.NET/C# MVP]" <mvp@spam.guard .caspershouse.c om> wrote
>>>>> in message news:u3hVLnqCGH A.3064@TK2MSFTN GP10.phx.gbl...
>>>>>
>>>>>>Peter,
>>>>>>
>>>>>> I highly recommend that you read up on how Garbage Collection works
>>>>>> exactly.
>>>>>
>>>>>
>>>>> I already know this.
>>>>
>>>> No, you obviously don't. The problem is not that the GC will take any
>>>> memory from your method, but that it is running in a separate thread. So
>>>> lets say you method executes in 1/10 s. When garbage collection occurs, it
>>>> will take way longer, simply because your method will halt in the middle of
>>>> something and resume when the GC is done. So from inside your method, the
>>>> execution time was still 1/10, but from the outside the execution time is
>>>> way longer ( A little bit like theory of relativity :-) ).
>>>>
>>>> Relying on the GC to do or not to do something is a capital sin in .NET.
>>>>
>>>>> One thing that it can not do is to reclaim memory that is still in use.
>>>> Correct, it will not try to get you memory, however it will stop you thread
>>>> if it wants to
>>>>> I remember reading the algorithm. It is some sort of aging system. In any
>>>>> case even if my memory needs to be constantly checked to see if it is
>>>>> still in use, I only need a single monolithic large block.
>>>> Yea, and while t checks and sees that it is not allowed to touch you
>>>> monolithic large block, you method will pause and take longer than 1/10s.
>>>>> One thing that I do know about GC, is that it is ONLY invoked when memory
>>>>> runs out, and is needed, otherwise it is never invoked.
>>>> One thing that you must know when developing managed code, is that you
>>>> *never* know when the GC is invoked.
>>>> Watch your performance counters for garbage collection. You'll be surprised
>>>> how busy the area :-)
>>>>
>>>> [snip]
>>>>
>>>> HTH,
>>>> Andy
>>>> --
>>>> To email me directly, please remove the *NO*SPAM* parts below:
>>>> *NO*SPAM*xmen40 @*NO*SPAM*gmx.n et
>>>
>>> Andreas,
>>>
>>> The only time the GC runs (un-forced) is when the creation of an object on
>>> the GC heap would overrun the gen0 heap threshold. When this happens the GC
>>> runs on the same thread as the object creator. That means that the GC won't
>>> run as long as you don't create objects instances.
>>> Note that this assumes there is no external memory pressure when there are
>>> extra GC heap segments allocated, this would force the CLR to start a full
>>> collection.
>>>
>>> Willy.
>>>
>>>[/color]
>> So it is like I said. My program will not implicitly invoke a garbage
>> collection cycle after it begins executing, if it needs a single fixed block
>> of memory the whole time that it is executing.
>>[/color]
>
> Be careful, if your function allocates that "block of memory" from the GC
> heap, it may get pre-empted by the CLR to perform a GC. You could force a GC
> run by calling GC.Collect() before you call the method, but this won't
> necessarily prevent a GC when you allocate a very large object in that method.[/color]

I don't care about a GC before I begin running, or any other GC that I did not
invoke.[color=blue]
>
> Willy.
>
>[/color]

[Peter Olcott]

Re: Can you write code directly in CIL ???


"Willy Denoyette [MVP]" <willy.denoyett e@telenet.be> wrote in message
news:%233iWaovC GHA.1032@TK2MSF TNGP11.phx.gbl. ..[color=blue]
>
> "Peter Olcott" <olcott@att.net > wrote in message
> news:IEbsf.3796 5$QW2.18916@duk eread08...[color=green]
>>
>> "Abubakar" <abubakarm@gmai l.com> wrote in message
>> news:%23tiR4prC GHA.3820@TK2MSF TNGP12.phx.gbl. ..[color=darkred]
>>> Hi,
>>>> Cab you write code directly in the Common Intermediate language? I need to
>>>> optimize a critical real-time function.
>>>
>>> ofcourse you can, by now you may even have done it. Just write few *.il
>>> lines and pass it to ilasm (that comes with the sdk) and you'll get the
>>> managed binary.
>>>
>>> although Nicholas tried explaning. I have just few things to add.
>>>
>>> 1- If you look at the shared source implementation of .net, ie, SSCLI (aka
>>> ROTOR), you wont find a single *.il file that microsoft devs had to write in
>>> order to acheive better performance. The max they did to write fast code as
>>> a .net code was to write the unsafe C# code (which uses pointers). Beyond
>>> that, places that needed to get maximum efficiency like JIT, they used a
>>> pure c++ code and in very few places, x86 assembly code was used. I think if
>>> those developers could acheive anything significant by writing il directly,
>>> they would have done that.[/color]
>> What I had in mind was to write the best possible code in C++ and have the
>> best compiler translate this into assembly language. The best compiler so far
>> seems to be Visual C++ 6.0. Some of the optimizations in 7.0 are disabled, in
>> particular function inlining. Then I was going to hand tweak this generated
>> assembly language. Then as a final step I was going to translate this into
>> CIL.
>>[color=darkred]
>>> 2- C# compiler is as clever in generating msil as anyone can possibly get. I[/color]
>> False assumption when one examines the benchmarks of managed C++ against
>> managed C#, Managed C++ does significantly better in at least some cases.
>>[/color]
>
> Not sure where you get this from? Did you actually run such benchmarks?
> I did run many benchmarks, since v1.0 comparing both C# and Managed C++ (and
> C++/CLI) and I never saw a delta (yes, for some C# is the winner) larger than
> 5%, using v2 they are even smaller.
>
>
>
> Willy.
>
>[/color]
I found it on the web, some of the differences were several-fold. I don't know
which versions.

[Peter Olcott]

Re: Can you write code directly in CIL ???


"Nicholas Paldino [.NET/C# MVP]" <mvp@spam.guard .caspershouse.c om> wrote in
message news:eb7Cj3vCGH A.4016@TK2MSFTN GP11.phx.gbl...[color=blue]
> I will second that the C++ compiler is better at optimizing IL output than
> the C# compiler. However, as Willy stated, it will not always produce
> verifiable code... I believe the article you were looking for is in MSDN
> magazine.[/color]

What do you mean by verifiable code?
[color=blue]
>
> But as a general statement, the C++ compiler generally has the best
> optimizations (and for unmanaged code, with the new profile-guided
> optimization, it's even cooler).
>
> --
> - Nicholas Paldino [.NET/C# MVP]
> - mvp@spam.guard. caspershouse.co m
>
> "Jon Skeet [C# MVP]" <skeet@pobox.co m> wrote in message
> news:MPG.1e1b36 c8c5e95e598cbe2 @msnews.microso ft.com...[color=green]
>> Abubakar <abubakarm@gmai l.com> wrote:[color=darkred]
>>> > It's a shame I can't find the newsgroup thread I'm thinking about - I
>>> > could give it a try with C# 2.0...
>>>
>>> btw what search engine are you using? It maybe socking for some people but
>>> few days back I was searching some thread and for the same keywords google
>>> could not find the post but msn search (search.msn.com ) did :)[/color]
>>
>> groups.google.c om, which is what I always use for newsgroup posts.
>> (Note: not just "web google".) It'll be there somewhere, but I just
>> can't find it at the moment...
>>
>> --
>> Jon Skeet - <skeet@pobox.co m>
>> http://www.pobox.com/~skeet Blog: http://www.msmvps.com/jon.skeet
>> If replying to the group, please do not mail me too[/color]
>
>[/color]

[Peter Olcott]

Re: Can you write code directly in CIL ???


"Jon Skeet [C# MVP]" <skeet@pobox.co m> wrote in message
news:MPG.1e1b84 c73d78be9098cbe 4@msnews.micros oft.com...[color=blue]
> Nicholas Paldino [.NET/C# MVP] <mvp@spam.guard .caspershouse.c om> wrote:[color=green]
>> I will second that the C++ compiler is better at optimizing IL output
>> than the C# compiler. However, as Willy stated, it will not always produce
>> verifiable code... I believe the article you were looking for is in MSDN
>> magazine.[/color]
>
> No, the article was definitely someone posting in this group saying, "I
> want to be able to embed IL in my C# code, here's why." He then
> produced some better IL (which I suspect *was* verifiable) which the C#
> compiler "could" have produced from the source C# (i.e. the behaviour
> was identical).
>
> I'm sure this will improve over time, but to be honest it's usually the
> JIT that has more to do with optimisation IMO.[/color]

I wouldn't think that this would be the case for two reasons:
(1) CIL (for the most part) forms a one-to-one mapping with assembly language
(2) End users are waiting on the JIT to complete, no time to waste doing
optimizations that could have been done before the softwae shipped.
[color=blue]
>[color=green]
>> But as a general statement, the C++ compiler generally has the best
>> optimizations (and for unmanaged code, with the new profile-guided
>> optimization, it's even cooler).[/color]
>
> Right.
>
> --
> Jon Skeet - <skeet@pobox.co m>
> http://www.pobox.com/~skeet Blog: http://www.msmvps.com/jon.skeet
> If replying to the group, please do not mail me too[/color]

[Peter Olcott]

Re: Can you write code directly in CIL ???


"Nicholas Paldino [.NET/C# MVP]" <mvp@spam.guard .caspershouse.c om> wrote in
message news:uGfzi2vCGH A.2300@TK2MSFTN GP15.phx.gbl...[color=blue]
> That's laughable, honestly, to think that 100 lines of C++ code will
> translate into 100 lines of C# code. It's a pretty blanket statement which
> can be shot down in a number of different ways.[/color]

Not any possible 100 lines of code, only the specific 100 lines of code that I
am referring to in my function. No OS calls. No memory management, just looping
and comparing.
[color=blue]
>
> Why not post the C++ code? Are you sure that all of the facilities that
> are available to you in that C++ code are available in .NET? Do you have to
> call other APIs? Are you sure there are all managed equivalents?
>
> I think it's time to either post the code, or let the thread die.
>
>
> --
> - Nicholas Paldino [.NET/C# MVP]
> - mvp@spam.guard. caspershouse.co m
>
> "Peter Olcott" <olcott@att.net > wrote in message
> news:9ybsf.3795 1$QW2.24780@duk eread08...[color=green]
>>
>> "Pohihihi" <noemail@hotmai l.com> wrote in message
>> news:e5TKP%23qC GHA.516@TK2MSFT NGP15.phx.gbl.. .[color=darkred]
>>> Your benchmarking on perfomance is bit off posting to posting. If it is 100
>>> lines of code in asm then surely it will be performing better but how many
>>> lines of .NET conversion of it. But if you are saying 100 lines of code in
>>> .Net then I wonder how many lines of instruction code your .net code is
>>> creating to execute it several million times in a given second or 10 of a
>>> second or which ever benchmark is correct.[/color]
>> It is currently writtten is Visual C++ 6.0 I tried compiling it with Visual
>> C++ 7.0, but this compiler produces poorer code quality by failing to inline
>> functions. My discussion of .NET is hypothetical. I am going to translate the
>> unmanaged C++ into managed C#. It is about 100 lines of unmanaged C++ now.
>> This will translate into about 100 lines of managed C#.
>>[color=darkred]
>>>
>>> Well anyways, seems like you know the ground you are playing on so for the
>>> answer for your original question, yes you can write the whole program in
>>> IL. I will be interested in knowing how you optimized it.
>>>
>>>
>>>
>>>
>>> "Peter Olcott" <olcott@att.net > wrote in message
>>> news:4S4sf.3793 7$QW2.7702@duke read08...
>>>> Not only will it run several million times every second, but, it will
>>>> constantly access all of its memory. Can I write a .NET component using
>>>> purely unmanaged code? That would seem to be a contradiction in terms.
>>>>
>>>> "Pohihihi" <noemail@hotmai l.com> wrote in message
>>>> news:e6$JcnqCGH A.916@TK2MSFTNG P10.phx.gbl...
>>>>> IMHO and according to the following link GC is way better than traditional
>>>>> memory mgmt. If method is running many million times a second (really??)
>>>>> then GC will keep it. But as Nicholas said, running of GC is a overhead
>>>>> and it is in control of CLR. Just because your code knows how much memory
>>>>> it needs it really do not mean that it will always have that in hand.
>>>>> Again GC is god here. If you want control of your code and how it behaves
>>>>> than leave managed environment and go for traditional C++/C/ASM route, or
>>>>> as suggested Interop.
>>>>>
>>>>> http://msdn.microsoft.com/library/de...tperftechs.asp
>>>>> section -->
>>>>> "Myth: Garbage Colloction Is Always Slower Than Doing It by Hand"
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> "Nicholas Paldino [.NET/C# MVP]" <mvp@spam.guard .caspershouse.c om> wrote
>>>>> in message news:%23YB$FaqC GHA.3820@TK2MSF TNGP12.phx.gbl. ..
>>>>>> Peter,
>>>>>>
>>>>>> You are missing the point completely. If you implement your code as
>>>>>> managed code, even in IL, you can't stop a GC no matter what. Your
>>>>>> thread is going to be pre-empted (in most situations, except if you have
>>>>>> the GC running on a separate thread) and it WILL stop and it WILL affect
>>>>>> your performance when it happens.
>>>>>>
>>>>>> Just because your code knows how much memory it needs doesn't mean
>>>>>> that you can pre-empt a GC. If it happens, it's going to happen, and
>>>>>> there is nothing you can do about it. Your 100-line function isn't going
>>>>>> to be able to stop it, and the CLR isn't going to care what your function
>>>>>> is doing.
>>>>>>
>>>>>> You can't just pretend its not going to happen. It does, and it will,
>>>>>> and you can't stop it. This isn't a choice you have if you are running
>>>>>> managed code, whether you do it in IL or not.
>>>>>>
>>>>>> This is what it means to have ^managed^ code. The CLR is going to
>>>>>> provide a good number of services, but you are going to have to pay for
>>>>>> them, and should be aware of how they impact your code.
>>>>>>
>>>>>> This is why I recommended that you use interop with your unmanaged
>>>>>> code. You will have your performance requirements fufilled, and not have
>>>>>> to worry about doing something that will ultimately be self-defeating.
>>>>>>
>>>>>> --
>>>>>> - Nicholas Paldino [.NET/C# MVP]
>>>>>> - mvp@spam.guard. caspershouse.co m
>>>>>>
>>>>>> "Peter Olcott" <olcott@att.net > wrote in message
>>>>>> news:GV3sf.3792 7$QW2.2410@duke read08...
>>>>>>>
>>>>>>> "Nicholas Paldino [.NET/C# MVP]" <mvp@spam.guard .caspershouse.c om> wrote
>>>>>>> in message news:uvvaatpCGH A.4004@tk2msftn gp13.phx.gbl...
>>>>>>>> Peter,
>>>>>>>>
>>>>>>>> You don't understand a fundamental concept to .NET and CIL. Yes,
>>>>>>>> there are compilers that will perform optimization of IL to a certain
>>>>>>>> degree.
>>>>>>>>
>>>>>>>> However, when the managed code is run, the CLR will take the CIL and
>>>>>>>> then compile it into native code. At this point in time, it is free to
>>>>>>>> optimize, or not optimize, or mangle your code in any way you want when
>>>>>>>> making the transition from CIL to native code.
>>>>>>>>
>>>>>>>> When you are dealing with assembly language in general, you have
>>>>>>>> complete control of what is going on, memory allocation, deallocation,
>>>>>>>> execution, etc, etc. With the CLR, this is taken out of your hands to
>>>>>>>> a degree.
>>>>>>>
>>>>>>> I don't care about these things they are not effecting my performance.
>>>>>>> What is effecting my performance are things such as the compiler failing
>>>>>>> to inline my functions code, and unnecessary overhead in the translation
>>>>>>> of a switch statement. My function will be always executed several
>>>>>>> million times every second. It must run concurrently with other
>>>>>>> applications.
>>>>>>>
>>>>>>>>
>>>>>>>> For example, have you considered, what happens when a Garbage
>>>>>>>> Collection (GC) occurs while your function is running? If it is in
>>>>>>>> complete managed code, then there is nothing that you can do about it,
>>>>>>>> and your function will resume running when the GC is complete.
>>>>>>>> Depending on what is happening on the machine at the time, combined
>>>>>>>> with what your program is doing, etc, etc, it is very feasible that
>>>>>>>> your code will take more than 1/10th of a second.
>>>>>>> My code knows exactly how much memory it needs at load time. It needs
>>>>>>> all of this memory the whole time that it executes. It would make no
>>>>>>> sense to have any garbage collection of my code's memory in this case. I
>>>>>>> want my code to be implemented as a .ET component.
>>>>>>>
>>>>>>>>
>>>>>>>> Just because it looks like assembly language, don't assume that CIL
>>>>>>>> is assembly language. There are some very different things going on
>>>>>>>> under the hood.
>>>>>>>>
>>>>>>>> --
>>>>>>>> - Nicholas Paldino [.NET/C# MVP]
>>>>>>>> - mvp@spam.guard. caspershouse.co m
>>>>>>>>
>>>>>>>> "Peter Olcott" <olcott@att.net > wrote in message
>>>>>>>> news:xj2sf.3790 6$QW2.34052@duk eread08...
>>>>>>>>>I want to be able to stick with purely managed code, if possible. I
>>>>>>>>>just need this 100 line function to run as fast as if it was hand
>>>>>>>>>tweake d assembly language. I have examined CIL, for the most part it is
>>>>>>>>>essent ially assembly language. From what I understand any optimizations
>>>>>>>>>take place before the CIL is generated. When I designed this system (in
>>>>>>>>>1998 ) I had hand tweaked assembly language in mind for this crucial
>>>>>>>>>functi on all along.
>>>>>>>>>
>>>>>>>>> "Nicholas Paldino [.NET/C# MVP]" <mvp@spam.guard .caspershouse.c om>
>>>>>>>>> wrote in message news:%23RjK3$oC GHA.2040@TK2MSF TNGP14.phx.gbl. ..
>>>>>>>>>> Peter,
>>>>>>>>>>
>>>>>>>>>> Not at all. When the CLR gets a hold of the JIT, it is free to
>>>>>>>>>> perform any optimizations it deems necessary, and that might not
>>>>>>>>>> necessarily be in line with what you are expecting.
>>>>>>>>>>
>>>>>>>>>> My recommendation would be to use Managed C++ to create a wrapper
>>>>>>>>>> to your unmanaged code which uses It Just Works (IJW, seriously). You
>>>>>>>>>> should get a managed interface, and the best possible performance
>>>>>>>>>> (for this specific situation, not all situations) between managed an
>>>>>>>>>> unmanaged code.
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> --
>>>>>>>>>> - Nicholas Paldino [.NET/C# MVP]
>>>>>>>>>> - mvp@spam.guard. caspershouse.co m
>>>>>>>>>>
>>>>>>>>>> "Peter Olcott" <olcott@att.net > wrote in message
>>>>>>>>>> news:_51sf.3789 8$QW2.37853@duk eread08...
>>>>>>>>>>>I need the best possible execution speed. I have found that there is
>>>>>>>>>>>a large difference in the quality of the code generated by the
>>>>>>>>>>>vari ous compilers. I have 16,000 hours of development time in my
>>>>>>>>>>>curr ent project. There is a 100 line function that must take no
>>>>>>>>>>>long er than 1/10 second to execute. I can just barely achieve this
>>>>>>>>>>>wi th MSVC++ 6.0. MSVC++ 7.0 has had some of its optimizations
>>>>>>>>>>>disa bled. I eventually will need to port this to C# .NET. This is a
>>>>>>>>>>>ca se where hand tweaked assembly language would be appropriate. I
>>>>>>>>>>>figu red that hand tweaked CIL would be the .NET equivalent of hand
>>>>>>>>>>>twea ked assembly language.
>>>>>>>>>>>
>>>>>>>>>>> "Nicholas Paldino [.NET/C# MVP]" <mvp@spam.guard .caspershouse.c om>
>>>>>>>>>>> wrote in message news:OCvd7unCGH A.2644@TK2MSFTN GP09.phx.gbl...
>>>>>>>>>>>> Peter,
>>>>>>>>>>>>
>>>>>>>>>>>> You can write it, but you would have to create a module with IL,
>>>>>>>>>>>> and then compile that into your assembly (or just write the whole
>>>>>>>>>>>> assembly).
>>>>>>>>>>>>
>>>>>>>>>>>> Also, what optimizations do you think you can make? Ultimately,
>>>>>>>>>>>> you suffer from the fact that Windows is not a real-time OS, and
>>>>>>>>>>>> nothing you can do will change that. On top of that, the JIT is
>>>>>>>>>>>> what's going to optimize your code again after you try to, so you
>>>>>>>>>>>> might actually end up hurting yourself more than helping yourself.
>>>>>>>>>>>>
>>>>>>>>>>>> If you post the code you are trying to optimize, we can try and
>>>>>>>>>>>> tell you where you might make some improvements, but dipping down
>>>>>>>>>>>> to the IL level is most likely not going to help you much.
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> --
>>>>>>>>>>>> - Nicholas Paldino [.NET/C# MVP]
>>>>>>>>>>>> - mvp@spam.guard. caspershouse.co m
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> "Peter Olcott" <olcott@att.net > wrote in message
>>>>>>>>>>>> news:7t%rf.3788 7$QW2.9998@duke read08...
>>>>>>>>>>>>> Cab you write code directly in the Common Intermediate language? I
>>>>>>>>>>>>> need to optimize a critical real-time function.
>>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>
>>>>>>
>>>>>
>>>>>
>>>>
>>>>
>>>
>>>[/color]
>>
>>[/color]
>
>[/color]

[Nicholas Paldino [.NET/C# MVP]]

Re: Can you write code directly in CIL ???

I wouldn't worry about it, since you are not worried by the multiple
posts by multiple people in this thread telling you things that you don't
want to hear.

--
- Nicholas Paldino [.NET/C# MVP]
- mvp@spam.guard. caspershouse.co m

"Peter Olcott" <olcott@att.net > wrote in message
news:Xaksf.3800 6$QW2.8948@duke read08...[color=blue]
>
> "Nicholas Paldino [.NET/C# MVP]" <mvp@spam.guard .caspershouse.c om> wrote
> in message news:eb7Cj3vCGH A.4016@TK2MSFTN GP11.phx.gbl...[color=green]
>> I will second that the C++ compiler is better at optimizing IL output
>> than the C# compiler. However, as Willy stated, it will not always
>> produce verifiable code... I believe the article you were looking for is
>> in MSDN magazine.[/color]
>
> What do you mean by verifiable code?
>[color=green]
>>
>> But as a general statement, the C++ compiler generally has the best
>> optimizations (and for unmanaged code, with the new profile-guided
>> optimization, it's even cooler).
>>
>> --
>> - Nicholas Paldino [.NET/C# MVP]
>> - mvp@spam.guard. caspershouse.co m
>>
>> "Jon Skeet [C# MVP]" <skeet@pobox.co m> wrote in message
>> news:MPG.1e1b36 c8c5e95e598cbe2 @msnews.microso ft.com...[color=darkred]
>>> Abubakar <abubakarm@gmai l.com> wrote:
>>>> > It's a shame I can't find the newsgroup thread I'm thinking about - I
>>>> > could give it a try with C# 2.0...
>>>>
>>>> btw what search engine are you using? It maybe socking for some people
>>>> but
>>>> few days back I was searching some thread and for the same keywords
>>>> google
>>>> could not find the post but msn search (search.msn.com ) did :)
>>>
>>> groups.google.c om, which is what I always use for newsgroup posts.
>>> (Note: not just "web google".) It'll be there somewhere, but I just
>>> can't find it at the moment...
>>>
>>> --
>>> Jon Skeet - <skeet@pobox.co m>
>>> http://www.pobox.com/~skeet Blog: http://www.msmvps.com/jon.skeet
>>> If replying to the group, please do not mail me too[/color]
>>
>>[/color]
>
>[/color]

[Peter Olcott]

Re: Can you write code directly in CIL ???

I have to screen out the good advice from the advice that does not apply to my
needs. With 16,000 hours of development in the current project, and the speed of
a single 100 line function making or breaking the success of this project, many
of the typical rules would not apply. One poster said that hand tweaked CIL
doubled the speed, thus confirming my estimations.

"Nicholas Paldino [.NET/C# MVP]" <mvp@spam.guard .caspershouse.c om> wrote in
message news:upn6lJ1CGH A.4004@tk2msftn gp13.phx.gbl...[color=blue]
> I wouldn't worry about it, since you are not worried by the multiple posts
> by multiple people in this thread telling you things that you don't want to
> hear.
>
> --
> - Nicholas Paldino [.NET/C# MVP]
> - mvp@spam.guard. caspershouse.co m
>
> "Peter Olcott" <olcott@att.net > wrote in message
> news:Xaksf.3800 6$QW2.8948@duke read08...[color=green]
>>
>> "Nicholas Paldino [.NET/C# MVP]" <mvp@spam.guard .caspershouse.c om> wrote in
>> message news:eb7Cj3vCGH A.4016@TK2MSFTN GP11.phx.gbl...[color=darkred]
>>> I will second that the C++ compiler is better at optimizing IL output
>>> than the C# compiler. However, as Willy stated, it will not always produce
>>> verifiable code... I believe the article you were looking for is in MSDN
>>> magazine.[/color]
>>
>> What do you mean by verifiable code?
>>[color=darkred]
>>>
>>> But as a general statement, the C++ compiler generally has the best
>>> optimizations (and for unmanaged code, with the new profile-guided
>>> optimization, it's even cooler).
>>>
>>> --
>>> - Nicholas Paldino [.NET/C# MVP]
>>> - mvp@spam.guard. caspershouse.co m
>>>
>>> "Jon Skeet [C# MVP]" <skeet@pobox.co m> wrote in message
>>> news:MPG.1e1b36 c8c5e95e598cbe2 @msnews.microso ft.com...
>>>> Abubakar <abubakarm@gmai l.com> wrote:
>>>>> > It's a shame I can't find the newsgroup thread I'm thinking about - I
>>>>> > could give it a try with C# 2.0...
>>>>>
>>>>> btw what search engine are you using? It maybe socking for some people but
>>>>> few days back I was searching some thread and for the same keywords google
>>>>> could not find the post but msn search (search.msn.com ) did :)
>>>>
>>>> groups.google.c om, which is what I always use for newsgroup posts.
>>>> (Note: not just "web google".) It'll be there somewhere, but I just
>>>> can't find it at the moment...
>>>>
>>>> --
>>>> Jon Skeet - <skeet@pobox.co m>
>>>> http://www.pobox.com/~skeet Blog: http://www.msmvps.com/jon.skeet
>>>> If replying to the group, please do not mail me too
>>>
>>>[/color]
>>
>>[/color]
>
>[/color]

[Jon Skeet [C# MVP]]

Re: Can you write code directly in CIL ???

Peter Olcott <olcott@att.net > wrote:[color=blue]
> I have to screen out the good advice from the advice that does not apply to my
> needs. With 16,000 hours of development in the current project, and the speed of
> a single 100 line function making or breaking the success of this project, many
> of the typical rules would not apply. One poster said that hand tweaked CIL
> doubled the speed, thus confirming my estimations.[/color]

I said it doubled the speed for one particular case, which was only
about four instructions. I wouldn't expect there to be much difference
(if any) normally.

How much more performance do you need? Have you tried doing the
conversion and seeing how it performs *without* tweaking?

--
Jon Skeet - <skeet@pobox.co m>
http://www.pobox.com/~skeet Blog: http://www.msmvps.com/jon.skeet
If replying to the group, please do not mail me too

[Abubakar]

Re: Can you write code directly in CIL ???

> I have to screen out the good advice from the advice that does not apply
to my[color=blue]
> needs. With 16,000 hours of development in the current project, and the[/color]
speed of[color=blue]
> a single 100 line function making or breaking the success of this project,[/color]
many[color=blue]
> of the typical rules would not apply. One poster said that hand tweaked[/color]
CIL[color=blue]
> doubled the speed, thus confirming my estimations.[/color]

I want to advise that you first study the framework details. You are wanting
to write the IL yourself which would be better than the C# compiler
generated output, and you dont yet know about verified code, details of GC,
etc. I think you would yet have to go through the complete clr instruction
set in order to pick the best instructions to best optimise the code. By now
you must have got an idea that in .net world (as opposed to c++) its going
to be extremely difficult to find people who occasionally hand code *.il
files to acheive better performance.

Ab.

"Peter Olcott" <olcott@att.net > wrote in message
news:QNosf.3802 0$QW2.8997@duke read08...[color=blue]
>[/color]

[Peter Olcott]

Re: Can you write code directly in CIL ???


"Jon Skeet [C# MVP]" <skeet@pobox.co m> wrote in message
news:MPG.1e1c3e 6d3294046298cbe a@msnews.micros oft.com...[color=blue]
> Peter Olcott <olcott@att.net > wrote:[color=green]
>> I have to screen out the good advice from the advice that does not apply to
>> my
>> needs. With 16,000 hours of development in the current project, and the speed
>> of
>> a single 100 line function making or breaking the success of this project,
>> many
>> of the typical rules would not apply. One poster said that hand tweaked CIL
>> doubled the speed, thus confirming my estimations.[/color]
>
> I said it doubled the speed for one particular case, which was only
> about four instructions. I wouldn't expect there to be much difference
> (if any) normally.
>
> How much more performance do you need? Have you tried doing the
> conversion and seeing how it performs *without* tweaking?[/color]

The fastest algorithm with the best compilation just barely meets my target.
This is with MS Visual C++ 6.0. The project requirements call for a .NET
component. If I could double the speed of this I would be very pleased. In any
case more recent compilers do not meet my target even with the best algorithm,
so I must do at least as well as the best compiler. This should only be a matter
of translating the generated assembly language from the best unmanaged code into
CIL.

[color=blue]
>
> --
> Jon Skeet - <skeet@pobox.co m>
> http://www.pobox.com/~skeet Blog: http://www.msmvps.com/jon.skeet
> If replying to the group, please do not mail me too[/color]

[Peter Olcott]

Re: Can you write code directly in CIL ???


"Abubakar" <abubakarm@gmai l.com> wrote in message
news:eGGVda3CGH A.4016@TK2MSFTN GP11.phx.gbl...[color=blue][color=green]
>> I have to screen out the good advice from the advice that does not apply[/color]
> to my[color=green]
>> needs. With 16,000 hours of development in the current project, and the[/color]
> speed of[color=green]
>> a single 100 line function making or breaking the success of this project,[/color]
> many[color=green]
>> of the typical rules would not apply. One poster said that hand tweaked[/color]
> CIL[color=green]
>> doubled the speed, thus confirming my estimations.[/color]
>
> I want to advise that you first study the framework details. You are wanting
> to write the IL yourself which would be better than the C# compiler
> generated output, and you dont yet know about verified code, details of GC,
> etc. I think you would yet have to go through the complete clr instruction
> set in order to pick the best instructions to best optimise the code. By now
> you must have got an idea that in .net world (as opposed to c++) its going
> to be extremely difficult to find people who occasionally hand code *.il
> files to acheive better performance.[/color]

Yet when a project with 16,000 hours invested can be made or broken by the speed
of a single 100 line function, this kind of optimization would be completely
appropriate. I am only at the feasibility study stage now. It definitely looks
feasible.
[color=blue]
>
> Ab.
>
> "Peter Olcott" <olcott@att.net > wrote in message
> news:QNosf.3802 0$QW2.8997@duke read08...[color=green]
>>[/color]
>
>[/color]