[llvm] [BOLT][runtime] Add start & fini symbols (PR #68505)

[Vladislav Khmelevsky via llvm-commits]

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@@ -4568,6 +4568,26 @@ void RewriteInstance::updateELFSymbolTable(
     }
   }
 
+  // Add runtime library start and fini address symbols
+  if (RuntimeLibrary *RtLibrary = BC->getRuntimeLibrary()) {
+    auto AddSymbol = [&](StringRef Name, uint64_t Address) {
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yota9 wrote:

It is not a principal question, but is there a logic behind marking new inserted symbols as weak? Basically I don't mind to move it upper, but I was curious about the logic on this.

https://github.com/llvm/llvm-project/pull/68505