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digitalmars.D - CT Intel's new language

reply janderson <askme me.com> writes:
Basically CT is C+++ which allows developers to write multicore code 
like they where programming for a single core.

http://www.informationweek.com/news/software/development/showArticle.jhtml?articleID=208403616

-Joel
Jun 13 2008
parent reply "Nick Sabalausky" <a a.a> writes:
"janderson" <askme me.com> wrote in message 
news:g2vdg7$2uls$1 digitalmars.com...

 Basically CT is C+++ which allows developers to write multicore code like 
 they where programming for a single core.

 http://www.informationweek.com/news/software/development/showArticle.jhtml?articleID=208403616

 -Joel


Another new natively-compiled C++ alternative? The cynic in me is tempted to 
say, "Watch that end up stealing all of D's potential user-base just because 
it has the backing of a major corporation."

But really, it'll be interesting to see how it pans out. And what exactly 
that "new 5%" is.
Jun 14 2008
parent reply Alix Pexton <_a_l_i_x_._p_e_x_t_o_n_ _g_m_a_i_l_._c_o_m_> writes:
Nick Sabalausky wrote:

 "janderson" <askme me.com> wrote in message 
 news:g2vdg7$2uls$1 digitalmars.com...

 Basically CT is C+++ which allows developers to write multicore code like 
 they where programming for a single core.

 http://www.informationweek.com/news/software/development/showArticle.jhtml?articleID=208403616

 -Joel


 
 Another new natively-compiled C++ alternative? The cynic in me is tempted to 
 say, "Watch that end up stealing all of D's potential user-base just because 
 it has the backing of a major corporation."
 
 But really, it'll be interesting to see how it pans out. And what exactly 
 that "new 5%" is. 
 
 


Maybe this article will help?

http://www.intel.com/technology/itj/2007/v11i4/7-future-proof/1-abstract.htm

I read about 5% before it went over my head ^^

A...
Jun 14 2008
parent reply janderson <askme me.com> writes:
Alix Pexton wrote:

 Nick Sabalausky wrote:

 "janderson" <askme me.com> wrote in message 
 news:g2vdg7$2uls$1 digitalmars.com...

 Basically CT is C+++ which allows developers to write multicore code 
 like they where programming for a single core.

 http://www.informationweek.com/news/software/development/showArticle.jhtml
articleID=208403616 


 -Joel


 Another new natively-compiled C++ alternative? The cynic in me is 
 tempted to say, "Watch that end up stealing all of D's potential 
 user-base just because it has the backing of a major corporation."

 But really, it'll be interesting to see how it pans out. And what 
 exactly that "new 5%" is.


 Maybe this article will help?
 
 http://www.intel.com/technology/itj/2007/v11i4/7-future-proof/1-abstract.htm 
 
 
 I read about 5% before it went over my head ^^
 
 A...


The main enhancement seems to be a vector class that can perform in 
Parallel.  That was on Walters to-do list for a long time, although it 
was taken out at some point.

CT doesn't have no pure functions so I think D will still come out on 
front eventually.  It would be nice when some benchmarks for the 
performance of pure functions can be demo straited.  If D could somehow 
tout it self as the next parallel programming language it has a real 
chance of taking off.

-Joel
Jun 14 2008
parent reply "Nick Sabalausky" <a a.a> writes:
"janderson" <askme me.com> wrote in message 
news:g311fe$fbl$1 digitalmars.com...

 The main enhancement seems to be a vector class that can perform in 
 Parallel.  That was on Walters to-do list for a long time, although it was 
 taken out at some point.


Hmm, yea, sounds like something D2 could already implement just by using 
some inline assembly (with proper use of "version()", of course) inside of 
the map/reduce/etc functions that already exist in a couple libraries.
Jun 14 2008
parent reply "Nick Sabalausky" <a a.a> writes:
"Nick Sabalausky" <a a.a> wrote in message 
news:g314r3$m01$1 digitalmars.com...

 "janderson" <askme me.com> wrote in message 
 news:g311fe$fbl$1 digitalmars.com...

 The main enhancement seems to be a vector class that can perform in 
 Parallel.  That was on Walters to-do list for a long time, although it 
 was taken out at some point.


 Hmm, yea, sounds like something D2 could already implement just by using 
 some inline assembly (with proper use of "version()", of course) inside of 
 the map/reduce/etc functions that already exist in a couple libraries.


Of course, couldn't the same thing be done in C++0x? (I dunno, it's been 
awhile since I've been up-to-date on the world of C++) So why make a new 
language out of it?

I just looked it up some more info. Looks like Ct is some sort of 
dynamically-compiled language/VM (hmm, maybe/maybe not a VM) that's 
callable/launchable through C++. The automatic adjustment of granularity 
sounds interesting. Although still don't think it's anything that couldn't 
be done in D (even if it meant writing a non-trivial new library).

From: http://techresearch.intel.com/articles/Tera-Scale/1514.htm
"How does it work?
In principal, Ct works with any standard C++ compiler because it is a 
standards-compliant C++ library (with a lot of runtime behind the scenes). 
When one initializes the Ct library, one loads a runtime that includes the 
compiler, threading runtime, memory manager — essentially all the components 
one needs for threaded and/or vectorized code generation. Ct code is 
dynamically compiled, so the runtime tries to aggregate as many smaller 
tasks or data parallel work quanta so that it can minimize threading 
overhead and control the granularity according to run-time conditions. With 
the Ct dynamic engine, one gets precise inter-procedural traces to compile, 
which is extremely useful in the highly modularized and indirect world of 
object-oriented programming."
Jun 14 2008
parent janderson <askme me.com> writes:
Nick Sabalausky wrote:

 "Nick Sabalausky" <a a.a> wrote in message 
 news:g314r3$m01$1 digitalmars.com...

 "janderson" <askme me.com> wrote in message 
 news:g311fe$fbl$1 digitalmars.com...

 The main enhancement seems to be a vector class that can perform in 
 Parallel.  That was on Walters to-do list for a long time, although it 
 was taken out at some point.


 Hmm, yea, sounds like something D2 could already implement just by using 
 some inline assembly (with proper use of "version()", of course) inside of 
 the map/reduce/etc functions that already exist in a couple libraries.


 
 Of course, couldn't the same thing be done in C++0x? (I dunno, it's been 
 awhile since I've been up-to-date on the world of C++) So why make a new 
 language out of it?
 
 I just looked it up some more info. Looks like Ct is some sort of 
 dynamically-compiled language/VM (hmm, maybe/maybe not a VM) that's 
 callable/launchable through C++. The automatic adjustment of granularity 
 sounds interesting. Although still don't think it's anything that couldn't 
 be done in D (even if it meant writing a non-trivial new library).
 
 From: http://techresearch.intel.com/articles/Tera-Scale/1514.htm
 "How does it work?
 In principal, Ct works with any standard C++ compiler because it is a 
 standards-compliant C++ library (with a lot of runtime behind the scenes). 
 When one initializes the Ct library, one loads a runtime that includes the 
 compiler, threading runtime, memory manager — essentially all the components 
 one needs for threaded and/or vectorized code generation. Ct code is 
 dynamically compiled, so the runtime tries to aggregate as many smaller 
 tasks or data parallel work quanta so that it can minimize threading 
 overhead and control the granularity according to run-time conditions. With 
 the Ct dynamic engine, one gets precise inter-procedural traces to compile, 
 which is extremely useful in the highly modularized and indirect world of 
 object-oriented programming."
 
 



Personally I'd like to simply do this:

float A[] = new float[100];
float B[] = new float[100];

A += B;
A *= B;

And have the compiler pick a good optimisation using SIMD, parallel 
processing / whatever.  It should be part of the standard or compiler, 
otherwise you can't say that D is any better then C++ in that regard.

I imagine there would be cases where the compiler could do better 
optimisation then a lib if it knew what these constructs means.

For instance, in its simplest form:

A = B - B; //Lib couldn't optimize this but D could

Note that something like this may be difficult for a user to optimize if 
it was spread across function boundaries, but D could as part of its 
inlining process.

Also SIMD and such offer mul and add operations that happen at the same 
time.  A compiler could easily pick these up automatically.  If it was 
in a lib the user would have to hand optimize each case which would make 
code harder to interpret.

ie in a lib user might go:

A.MulAdd(B, C)

If the compiler knew about this it could easily optimize:

A *= B;
A += B;


And something like:

A *= B;
A *= C;

Each line could be put in a separate thread.

The compiler would have to have some heretic which would decide what 
optimisation route to take.  It may even be able to hot-swap the code 
when the application begins.  Maybe eventually the heretic could be 
exposed to the programmer so they could optimize it and maybe eventually 
a reasonably optimal heretic would be created.

-Joel
Jun 14 2008