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digitalmars.D.learn - CUDA with D?

reply Trass3r <mrmocool gmx.de> writes:
Is there any tutorial or code for using CUDA with D?
Feb 18 2009
parent reply Chris R Miller <lordsauronthegreat gmail.com> writes:
Trass3r wrote:

 Is there any tutorial or code for using CUDA with D?



Short answer: no.

I looked into writing CUDA with D a while back.  The problem is that the 
CUDA C runtime and the D runtime are 100% incompatible.  CUDA works by 
taking C-like code and compiling it with a special NVCC compiler, which 
emits code that's specifically for NVIDIA GPUs.

I found that it would be *possible* to take NVCC and write a D-frontend 
for it (The MathWorks did it for their MATLAB language), but that was a 
lot more work that I was willing to do in order to do stupid things like 
see how fast my graphics card can count to a million.

I hope you have better luck!  Maybe something has changed... maybe an 
LLVM->NVCC bridge (so you could take the LDC frontend and plug it into 
NVCC and there you go?  I don't know, it'd be cool, but I *highly* doubt 
it exists).
Feb 23 2009
next sibling parent reply Lutger <lutger.blijdestijn gmail.com> writes:
Chris R Miller wrote:


 Trass3r wrote:

 Is there any tutorial or code for using CUDA with D?



 Short answer: no.
 
 I looked into writing CUDA with D a while back.  The problem is that the 
 CUDA C runtime and the D runtime are 100% incompatible.  CUDA works by 
 taking C-like code and compiling it with a special NVCC compiler, which 
 emits code that's specifically for NVIDIA GPUs.
 
 I found that it would be *possible* to take NVCC and write a D-frontend 
 for it (The MathWorks did it for their MATLAB language), but that was a 
 lot more work that I was willing to do in order to do stupid things like 
 see how fast my graphics card can count to a million.
 
 I hope you have better luck!  Maybe something has changed... maybe an 
 LLVM->NVCC bridge (so you could take the LDC frontend and plug it into 
 NVCC and there you go?  I don't know, it'd be cool, but I *highly* doubt 
 it exists).



I think OpenCL will be easier and work om AMD to boot.
Feb 23 2009
parent Trass3r <mrmocool gmx.de> writes:
Lutger schrieb:

 I think OpenCL will be easier and work om AMD to boot.
 



If they ever release it in the next few months ;)
Feb 24 2009
prev sibling parent reply Trass3r <mrmocool gmx.de> writes:
Chris R Miller schrieb:

 Trass3r wrote:

 Is there any tutorial or code for using CUDA with D?



 Short answer: no.
 
 I looked into writing CUDA with D a while back.  The problem is that the 
 CUDA C runtime and the D runtime are 100% incompatible.  CUDA works by 
 taking C-like code and compiling it with a special NVCC compiler, which 
 emits code that's specifically for NVIDIA GPUs.
 



What a pity, just read that article and thought it might be possible to 
get it to work:
http://www.ddj.com/architect/211800683

But thanks for your answer. Saves me some time ;)
Feb 24 2009
parent reply Chris R Miller <lordsauronthegreat gmail.com> writes:
Trass3r wrote:

 Chris R Miller schrieb:

 Trass3r wrote:

 Is there any tutorial or code for using CUDA with D?



 Short answer: no.

 I looked into writing CUDA with D a while back. The problem is that
 the CUDA C runtime and the D runtime are 100% incompatible. CUDA works
 by taking C-like code and compiling it with a special NVCC compiler,
 which emits code that's specifically for NVIDIA GPUs.



 What a pity, just read that article and thought it might be possible to
 get it to work:
 http://www.ddj.com/architect/211800683

 But thanks for your answer. Saves me some time ;)



And I quote:

# A more flexible and powerful capability lies in the ability of many
# languages -- such as Python, Perl, and Java -- to be extended through
# modules written in C, or CUDA when programming for GPU environments.

You're still writing in C, just using D to make an (extern) function 
call.  So it's not exactly D on the GPU, so I don't think it counts - 
plus the build sequence to build the C part with GCC->NVCC pass-through 
(or the MSVC->NVCC pass-through) would be a absolute nightmare to work with.

I looked into OpenCL, which appears (at first glance) to be a funky way 
of stringing together assembler instructions using C function calls. 
I'm sure it's fast, but it's not the most friendly looking code to me 
(then again, I don't know ASM, so what do I know?)
Mar 01 2009
next sibling parent reply Lutger <lutger.blijdestijn gmail.com> writes:
Chris R Miller wrote:
...

 
 I looked into OpenCL, which appears (at first glance) to be a funky way 
 of stringing together assembler instructions using C function calls. 
 I'm sure it's fast, but it's not the most friendly looking code to me 
 (then again, I don't know ASM, so what do I know?)



It's at a higher level than that, basically shaders for more general purpose 
parallel computation BUT: the OpenCL runtime is supposed to take that code 
and load balance it over whatever processors it can find in your system, 
GPU's, multiple cores with or without SIMD instructions, whatever.
Mar 01 2009
next sibling parent Chris R Miller <lordsauronthegreat gmail.com> writes:
Lutger wrote:

 Chris R Miller wrote:
 ...

 I looked into OpenCL, which appears (at first glance) to be a funky way
 of stringing together assembler instructions using C function calls.
 I'm sure it's fast, but it's not the most friendly looking code to me
 (then again, I don't know ASM, so what do I know?)



 It's at a higher level than that, basically shaders for more general purpose
 parallel computation BUT: the OpenCL runtime is supposed to take that code
 and load balance it over whatever processors it can find in your system,
 GPU's, multiple cores with or without SIMD instructions, whatever.



Hmm, clever.
Mar 03 2009
prev sibling parent Trass3r <mrmocool gmx.de> writes:
Lutger schrieb:

 It's at a higher level than that, basically shaders for more general purpose 
 parallel computation BUT: the OpenCL runtime is supposed to take that code 
 and load balance it over whatever processors it can find in your system, 
 GPU's, multiple cores with or without SIMD instructions, whatever. 
 



I think that's not fully correct. You specify yourself which processor 
the code should run on.
May 05 2009
prev sibling parent Trass3r <mrmocool gmx.de> writes:
Chris R Miller schrieb:

 You're still writing in C, just using D to make an (extern) function 
 call.  So it's not exactly D on the GPU, so I don't think it counts - 
 plus the build sequence to build the C part with GCC->NVCC pass-through 
 (or the MSVC->NVCC pass-through) would be a absolute nightmare to work 
 with.
 



Well, that's what I thought about cause real D code on the GPU seems 
utopian.


 I looked into OpenCL, which appears (at first glance) to be a funky way 
 of stringing together assembler instructions using C function calls. I'm 
 sure it's fast, but it's not the most friendly looking code to me (then 
 again, I don't know ASM, so what do I know?)



OpenCL is really similar to CUDA, in fact nvidia will support it using CUDA.
It also uses an extended subset of C99 which will be somehow compiled. 
Still wondering how it will work, hopefully it won't have that same 
problem with the incompatible runtime :(
Mar 19 2009