It's actually not the same thing. I've looked at the PTX disassembly and the difference is that the OpenCL code must perform a dereference while the CUDA code c

It's actually not the same thing. I've looked at the PTX disassembly and the difference is that the OpenCL code must perform a dereference while the CUDA code can use a fixed address, (relocatable of course.) The address is relocated based on the loaded base address of the kernel module. So there is a huge gain for certain types of code to save an instruction and possible warping, cache miss, register pressure, etc. Right, OpenCL runs on the Knights Corner/Bridge (PHI - what a piece of crap btw), CPUs, and many other devices, it has its place. And CUDA does too. I write CUDA when I'm on Nvidia devices because of the dereferencing performance as well as the slight speed gain that the double-buffering of workgroups that CUDA supports slightly better than OpenCL. All in all, they're pretty on par, I'm fond of CUDA a little more due to the clarity of its driver API and non-evented model. It's a little bit easier to work with. Anyhow, I think we're done here. I got you to admit that CUDA isn't a piece of monopolistic smudgenry. Which is really all I wanted :-)