Re: [proto] Other methods for embedding DSL in C++
On 26/07/10 21:36, Manjunath Kudlur wrote: If you have to do heavy-weight things like optimizing the generated AST, you got to anyway do it at runtime. You can still inspect the code, transform it, etc at runtime. (Note : I am not trying to defend the runtime retained execution model. I am a big fan of Proto. I am just trying to understand the differences and see where each model makes sense). I'm biased as I mostly do HPC DSL but for me wastiung RT cycles to do stuff which are fully statis is useless. The only thign RT shoudl bring is specialization over RT onyl data (liek data set size etc). ___ proto mailing list proto@lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/proto
Re: [proto] Other methods for embedding DSL in C++
On 26/07/10 21:52, Eric Niebler wrote: I confess I'm having a hard time seeing how the code posted in Manjunath's original email could result in something that can be introspected at runtime. Does it generate byte code? A runtime polymorphic AST? And the JIT ... does it actually generate machine code that then gets executed? Yeah screw introspection. It usually generates C code in a string then JIT it using w/e compiler is lying around. Manjunath asked about why this technique is popular in industry. I don't know; I've never heard about it before. Is it because it's easier then programming with expression templates? Maybe had proto been available earlier we'd see more ET-based DSELs today. That could just be my ego talking. ;- Popular != pushed by Intel/Google. For me it's a bad solution. Hence why we look at CT-EDSL ___ proto mailing list proto@lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/proto
Re: [proto] Other methods for embedding DSL in C++
I confess I'm having a hard time seeing how the code posted in Manjunath's original email could result in something that can be introspected at runtime. Does it generate byte code? A runtime polymorphic AST? And the JIT ... does it actually generate machine code that then gets executed? At the end of the END block, you would have an AST. Yes, there will be a JIT and an associated run time to compile this and run on different platforms. P.S : Someone more familiar with Rapidmind or other variants, can you please explain how they do it in more detail? Rapidmind is one huge vaporware. Nobody ever saw it running ... Manjunath asked about why this technique is popular in industry. I don't know; I've never heard about it before. Is it because it's easier then programming with expression templates? Maybe had proto been available You wouldn't believe how many of my otherwise expert C++ programmer friends get a disgusted look on their face when they see templates. I couldn't figure out why :( That being said, I see one obvious advantage with proto. With proto, when you write an expression like if_(a b) [c = d + 2.0*a].else_[c = d-2.0*a] you can just natively execute it. But with RT-DSLs, you have to generate an AST by running the code, then JIT and only then you can execute it. If you wanted a system where you can just natively interpret you program, or generate code for different platforms, then proto makes the interpreter very fast. Whereas with RT-DSLs, even interpreting has to be differed to run time. Manjunath ___ proto mailing list proto@lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/proto
Re: [proto] Other methods for embedding DSL in C++
On 26/07/10 22:12, Eric Niebler wrote: Convincing people of what in your article? That C++ EDSL are good thanks to templae meta-programming in general That compile-time introspection is a Good Thing? Among other What are the complaints you hear most often? It's C++ ?!? Why not making a real compiler ? Seriously, you CAN NOT get that fast, you're cheating Who use C++ anyway ? Again Expression Tempaltes, ok, that's old, please move on how do you compare to insert JAVA based library, that's real industrial strength system ! authors should focus on real benchmarks (like dot product) insetad of this lengthy useless implementation description (Which article, btw?) Among other: http://dl.dropbox.com/u/3819406/edsl/parco_07.pdf http://dl.dropbox.com/u/3819406/edsl/europar_08.pdf http://dl.dropbox.com/u/3819406/edsl/pact_09.pdf Note that most predates proto but are basically hand made C++ EDSL with Expression Templates. The pact paper is made out of proto though. ___ proto mailing list proto@lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/proto
