[llvm] llvm-dwarfdump --verify aggregated output to JSON file (PR #81762)

[Greg Clayton via llvm-commits]

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@@ -2026,12 +2028,36 @@ void OutputCategoryAggregator::EnumerateResults(
 }
 
 void DWARFVerifier::summarize() {
-  if (ErrorCategory.GetNumCategories() && DumpOpts.ShowAggregateErrors) {
+  if (!ErrorCategory.GetNumCategories())
+    return;
+  if (DumpOpts.ShowAggregateErrors) {
     error() << "Aggregated error counts:\n";
     ErrorCategory.EnumerateResults([&](StringRef s, unsigned count) {
       error() << s << " occurred " << count << " time(s).\n";
     });
   }
+  if (!DumpOpts.AggregateErrJsonFile.empty()) {
+    std::error_code EC;
+    raw_fd_ostream JsonStream(DumpOpts.AggregateErrJsonFile, EC,
+                              sys::fs::OF_Text);
+    if (EC) {
+      error() << "error opening aggregate error json file '"
+              << DumpOpts.AggregateErrJsonFile
+              << "' for writing: " << EC.message() << '\n';
+      return;
+    }
+    JsonStream << "{\"errors\":[\n";
+    bool prev = false;
+    ErrorCategory.EnumerateResults([&](StringRef category, unsigned count) {
+      if (prev)
+        JsonStream << ",\n";
+      JsonStream << "{\"category\":\"";
+      llvm::printEscapedString(category, JsonStream);
+      JsonStream << "\",\"count\":" << count << "}";
+      prev = true;
+    });
+    JsonStream << "\n]}\n";
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clayborg wrote:

Like gsym patch, use llvm::json objects to create the JSON, then convert to a string. This helps ensure that we emit valid JSON. Here if the category strings have special JSON reserved characters, it would create invalid JSON

https://github.com/llvm/llvm-project/pull/81762