[clang] [llvm] [RISCV] Inline Assembly Support for GPR Pairs ('Pr') (PR #112983)

[Sam Elliott via cfe-commits]

lenary wrote:

Today's changes address all the CI failures, by adding better checking before turning BITCAST into `BuildPairF64` or `SplitF64` - the conditions are derived from the conditions on `setOperationAction(ISD::BITCAST, MVT::i64, Custom)` before this patch added more of the same. 

https://github.com/llvm/llvm-project/pull/112983