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0 pointsCyberDildonics9y ago0 comments

You've almost described ISPC verbatim. If you don't already know about it you might want to check it out. http://ispc.github.io/index.html

It doesn't compile to a native executable, but since it produces .o files you should be able to just set your entry point and go from there.

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exDM699y ago

> You've almost described ISPC verbatim.

Thanks, I've read about it before, but haven't spent too much time looking at it.

However, this "single program, multiple data" isn't exactly what I'm looking for (it would solve the sin4f vs. sin8f issue mentioned above, though). I need explicit, low level access to SIMD, coupled with genericity over vector widths. This means doing almost assembly-style SIMD code with explicit shuffles, blending, etc as well as access to intrinsics where needed.

I also need portability (ispc is from Intel, it probably doesn't support ARM NEON) and targetting GPUs.

I'm very well aware that my needs are very specific. I need to do math stuff for 3d graphics and physics applications.

All I need is for a lot of free time to appear from out of nowhere and I can write a prototype compiler for this myself :)

CyberDildonicsOP9y ago

How would you use specific instructions yet have widths abstracted?

ISPC actually has some preliminary support for targeting Nvidia PTX btw. It compiles using LLVM.

exDM699y ago

See example above in this thread. In C + GCC vector extensions, I just use normal arithmetic operations (+, -, *, /).

However, when using specific intrinsics they are for a specific width. It might take some "library code" to take advantage of some instructions like dot products, etc.

j / k navigate · click thread line to collapse

0 comments

exDM699y ago

> You've almost described ISPC verbatim.

Thanks, I've read about it before, but haven't spent too much time looking at it.

I also need portability (ispc is from Intel, it probably doesn't support ARM NEON) and targetting GPUs.

I'm very well aware that my needs are very specific. I need to do math stuff for 3d graphics and physics applications.

All I need is for a lot of free time to appear from out of nowhere and I can write a prototype compiler for this myself :)

CyberDildonicsOP9y ago

How would you use specific instructions yet have widths abstracted?

ISPC actually has some preliminary support for targeting Nvidia PTX btw. It compiles using LLVM.

exDM699y ago

See example above in this thread. In C + GCC vector extensions, I just use normal arithmetic operations (+, -, *, /).

However, when using specific intrinsics they are for a specific width. It might take some "library code" to take advantage of some instructions like dot products, etc.

j / k navigate · click thread line to collapse