[llvm] [BOLT][RISCV] Implement basic instrumentation (PR #71664)

[Amir Ayupov via llvm-commits]

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@@ -0,0 +1,94 @@
+#ifndef LLVM_TOOLS_LLVM_BOLT_SYS_RISCV64
+#define LLVM_TOOLS_LLVM_BOLT_SYS_RISCV64
+
+#include <dirent.h>
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aaupov wrote:

As I mentioned on another PR, the clean solution would probably be to move to `runtimes` build model (sanitizer, instrumentation runtimes etc). This should enable proper native and cross- compilation. But since we're not there yet, I'd stick with hard-coded definitions for syscall numbers.

https://github.com/llvm/llvm-project/pull/71664