[llvm] [NVPTX] Add intrinsics for the szext instruction (PR #139126)

[Artem Belevich via llvm-commits]

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@@ -568,6 +568,99 @@ to left-shift the found bit into the most-significant bit position, otherwise
 the result is the shift amount needed to right-shift the found bit into the
 least-significant bit position. 0xffffffff is returned if no 1 bit is found.
 
+'``llvm.nvvm.zext.inreg.clamp``' Intrinsic
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Artem-B wrote:

Do we need the `inreg` part? 

It sounds like an implementation detail at best, and misleading, at worst. I.e. I'd assume that it implies in-place (i.e. in the same register) conversion, which is not the case. 

https://github.com/llvm/llvm-project/pull/139126