[clang] [llvm] [RISCV][VLS] Support RISCV VLS calling convention (PR #100346)

[Brandon Wu via llvm-commits]

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@@ -1333,6 +1333,15 @@ def Experimental
    : SubtargetFeature<"experimental", "HasExperimental",
                       "true", "Experimental intrinsics">;
 
+def FeatureABIVLen32B
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4vtomat wrote:

Yeah, that's a good idea since the backend doesn't use them~

https://github.com/llvm/llvm-project/pull/100346