[lld] [llvm] [LLD][COFF] Add more `--time-trace` tags for ThinLTO linking (PR #156471)

[Teresa Johnson via llvm-commits]

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@@ -1440,8 +1440,12 @@ void SymbolTable::compileBitcodeFiles() {
   llvm::TimeTraceScope timeScope("Compile bitcode");
   ScopedTimer t(ctx.ltoTimer);
   lto.reset(new BitcodeCompiler(ctx));
-  for (BitcodeFile *f : bitcodeFileInstances)
-    lto->add(*f);
+  {
+    llvm::TimeTraceScope addScope("Add bitcode file instances");
+    for (BitcodeFile *f : bitcodeFileInstances)
+      lto->add(*f);
+  }
+  llvm::TimeTraceScope compileScope("LTO compile");
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teresajohnson wrote:

There's already a "Compile bitcode" TimeTraceScope just above in the same scope. Is this needed too?

https://github.com/llvm/llvm-project/pull/156471