[llvm] [RISCV][MC] Implement ISA mapping symbols (PR #67541)

[Craig Topper via llvm-commits]

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@@ -34,7 +34,7 @@ void RISCVTargetStreamer::emitDirectiveOptionNoRVC() {}
 void RISCVTargetStreamer::emitDirectiveOptionRelax() {}
 void RISCVTargetStreamer::emitDirectiveOptionNoRelax() {}
 void RISCVTargetStreamer::emitDirectiveOptionArch(
-    ArrayRef<RISCVOptionArchArg> Args) {}
+    const ArrayRef<RISCVOptionArchArg> &Args) {}
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topperc wrote:

ArrayRef should always be passed by value. It's cheap to copy. It's a pointer and size.

https://github.com/llvm/llvm-project/pull/67541