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

[Andy Kaylor via llvm-commits]

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@@ -984,6 +987,9 @@ lltok::Kind LLLexer::LexIdentifier() {
 ///    HexPPC128Constant 0xM[0-9A-Fa-f]+
 ///    HexHalfConstant   0xH[0-9A-Fa-f]+
 ///    HexBFloatConstant 0xR[0-9A-Fa-f]+
+///    HexDecimal32Constant 0xR[0-9A-Fa-f]+
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andykaylor wrote:

You probably need three different prefixes where 0xR is used here. The same prefix is used for all IEEE FP constants. You might be able to use one encoding for all the decimal types, but the decimal format is a little tricky and I'm not sure that would work in this case. In fact, we might even need different encoding for BID and DPD constants. I'm not sure they are always directly convertible. I'd like to ask someone from the Numerics team about this.

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