[llvm] [Exegesis][RISCV] Add RISCV support for llvm-exegesis (PR #89047)

[via llvm-commits]

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@@ -133,6 +135,10 @@ struct CodeTemplate {
   // the pointer to this memory is passed in to the function.
   unsigned ScratchSpacePointerInReg = 0;
 
+  // Require to pre-store value of a given register (fisrt)
+  // to scratch memory with given offset (second)
+  SmallVector<std::pair<unsigned, unsigned>, 2> PreinitScratchMemory;
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AnastasiyaChernikova wrote:

It use in llvm/tools/llvm-exegesis/lib/SerialSnippetGenerator.cpp:
`151    CT.PreinitScratchMemory.emplace_back(ScratchMemoryRegister, /* Offset */ 0);`

https://github.com/llvm/llvm-project/pull/89047