[llvm] Implement getIPRACSRegs hook for riscv (PR #125586)

[Craig Topper via llvm-commits]

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@@ -68,21 +68,25 @@ define internal void @foobar(ptr %live_throughout.0.val) norecurse nounwind {
 ; RV64-LABEL: foobar:
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topperc wrote:

Need to remove the FIXME

https://github.com/llvm/llvm-project/pull/125586