Many backends are missing either all tests for lrint, or specifically
those for f16, which currently crashes for `softPromoteHalf` targets.
For a number of popular backends, do the following:
* Ensure f16, f32, f64, and f128 are all covered
* Ensure both a 32- and 64-bit target are tested, if relevant
* Add `nounwind` to clean up CFI output
* Add a test covering the above if one did not exist
* Always specify the integer type in intrinsic calls
There are quite a few FIXMEs here, especially for `f16`, but much of
this will be resolved in the near future.
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