[llvm] [MCA][RISCV]Enable latency instrument on RISCV (PR #160063)

[Min-Yih Hsu via llvm-commits]

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@@ -110,8 +111,9 @@ RISCVInstrumentManager::createInstrument(llvm::StringRef Desc,
     return std::make_unique<RISCVSEWInstrument>(Data);
   }
 
-  LLVM_DEBUG(dbgs() << "RVCB: Unknown instrumentation Desc: " << Desc << '\n');
-  return nullptr;
+  LLVM_DEBUG(dbgs() << "RVCB: Creating default instrument for Desc: " << Desc
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mshockwave wrote:

nit: `LDBG` was introduced recently (https://www.llvm.org/docs/ProgrammersManual.html#the-ldbg-and-llvm-debug-macros-and-debug-option) could we use that here?

https://github.com/llvm/llvm-project/pull/160063