[clang] [clang][analyzer] Make per-entry-point metric rows uniquely identifiable (PR #161663)

[Donát Nagy via cfe-commits]

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@@ -65,6 +65,15 @@ STAT_MAX(MaxCFGSize, "The maximum number of basic blocks in a function.");
 
 namespace {
 
+StringRef getMainFileName(const CompilerInvocation &Invocation) {
+  if (!Invocation.getFrontendOpts().Inputs.empty()) {
+    const FrontendInputFile &Input = Invocation.getFrontendOpts().Inputs[0];
+    return Input.isFile() ? Input.getFile()
+                          : Input.getBuffer().getBufferIdentifier();
+  }
+  return {};
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NagyDonat wrote:

What about returning a human-readable placeholder like `"<no input>"` in this case? I would guess that it would be more helpful (e.g. easier to search for) if someone runs into this rare corner case.

https://github.com/llvm/llvm-project/pull/161663