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

[Jessica Clarke via llvm-commits]

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@@ -140,7 +141,10 @@ void RISCVELFStreamer::emitDataMappingSymbol() {
 void RISCVELFStreamer::emitInstructionsMappingSymbol() {
   if (LastEMS == EMS_Instructions)
     return;
-  emitMappingSymbol("$x");
+  if (LastEMS == EMS_ChangeISA)
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jrtc27 wrote:

Why can't we just infer this in the ELF streamer rather than introduce this extra state?

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