[llvm] [ConstantFPRange] Add support for cast operations (PR #162686)

[Matt Arsenault via llvm-commits]

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@@ -391,3 +391,21 @@ ConstantFPRange ConstantFPRange::unionWith(const ConstantFPRange &CR) const {
   return ConstantFPRange(minnum(Lower, CR.Lower), maxnum(Upper, CR.Upper),
                          MayBeQNaN | CR.MayBeQNaN, MayBeSNaN | CR.MayBeSNaN);
 }
+
+ConstantFPRange ConstantFPRange::cast(const fltSemantics &DstSem) const {
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arsenm wrote:

Just pass through the rounding mode argument? Is there anything more to it necessary than just passing it through to convert? 

https://github.com/llvm/llvm-project/pull/162686