[LLVMdev] Behaviour of NVPTX intrinsic

[Jingyue Wu]

I can't think of any NVPTX intrinsic that disallow even arithmetic
instructions.

If you are trying to read some special registers in PTX, can you use inline
assembly and mark it as having side effects? I think LLVM's optimizer is
very conservative about inline assembly marked with sideeffect, and will
probably solve your code motion issue.

Jingyue

On Tue Sep 30 2014 at 11:03:45 AM RAVI KORSA <ravi.korsa at gmail.com> wrote:

> The actual purpose that I wanted such an intrinsic is to solve a problem
> similar to this one in X86. Say I wanted to read the "mxcsr" register(which
> is the status register for SSE instructions) after a particular
> instruction, then I need a kind of barrier intrinsic which will not allow
> the arithmetic instructions to move around it. Or else I will be reading
> the status of some other instruction.
>
> Thanks
>
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