[llvm] [RISCV][GISel] Support G_MERGE_VALUES/G_UNMERGE_VALUES with Zfa. (PR #120379)

[Matt Arsenault via llvm-commits]

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@@ -23,7 +23,9 @@ def SDT_RISCVSplitF64     : SDTypeProfile<2, 1, [SDTCisVT<0, i32>,
                                                  SDTCisVT<2, f64>]>;
 
 def RISCVBuildPairF64 : SDNode<"RISCVISD::BuildPairF64", SDT_RISCVBuildPairF64>;
+def : GINodeEquiv<G_MERGE_VALUES, RISCVBuildPairF64>;
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arsenm wrote:

If you have more variants of RISCVBuildPairF64, you'd eventually need some custom emitter code to differentiate them 

https://github.com/llvm/llvm-project/pull/120379