[llvm] Add support for DFP IR type. (PR #69718)

[Andy Kaylor via llvm-commits]

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@@ -207,9 +216,15 @@ int Type::getFPMantissaWidth() const {
   if (getTypeID() == HalfTyID) return 11;
   if (getTypeID() == BFloatTyID) return 8;
   if (getTypeID() == FloatTyID) return 24;
+  // TODO - Does this depend on the encoding format used (BID or DPD)?
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andykaylor wrote:

What I meant by "give them an explicit check" was something like "if (getTypeID() == Decimal32TyID) return -1;" It's functionally equivalent but I think it reads better.

https://github.com/llvm/llvm-project/pull/69718