[llvm] [RFC][SPIR-V] Add llvm.arbitrary.fp.convert intrinsic (PR #164252)

[Matt Arsenault via llvm-commits]

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@@ -21406,6 +21406,69 @@ environment <floatenv>` *except* for the rounding mode.
 This intrinsic is not supported on all targets. Some targets may not support
 all rounding modes.
 
+'``llvm.arbitrary.fp.convert``' Intrinsic
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Syntax:
+"""""""
+
+::
+
+      declare <type> @llvm.arbitrary.fp.convert(
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arsenm wrote:

I don't like the arbitrary in the name 

https://github.com/llvm/llvm-project/pull/164252