Strict fp-to-int and int-to-fp conversions can be handled in the same way that
the non-strict versions are (by using the appropriate instruction or converting
to a function call when we have no instruction).
Differential Revision: https://reviews.llvm.org/D73625
This started with adding a test to support get code coverage on
ScalarizeVecOp_UnaryOp_StrictFP by copying an existing AArch64 test
and using constrained sitofp/uitofp intrinsics.
This found 3 separate issues:
-ScalarizeVecOp_UnaryOp_StrictFP needs to do its own replacement
because the caller can't handle replacing multiple results.
-Missing integer promotion support for sitofp/uitofp
-Chain result not always assigned in ExpandLegalINT_TO_FP.
Committing them together so I can add the test case.