1 files changed, 14 insertions, 0 deletions
diff --git a/llvm/lib/Analysis/ModuleSummaryAnalysis.cpp b/llvm/lib/Analysis/ModuleSummaryAnalysis.cpp
index 76a0b048493..58bf469493b 100644
--- a/llvm/lib/Analysis/ModuleSummaryAnalysis.cpp
+++ b/llvm/lib/Analysis/ModuleSummaryAnalysis.cpp
@@ -70,6 +70,11 @@ cl::opt<FunctionSummary::ForceSummaryHotnessType, true> FSEC(
                           "all-non-critical", "All non-critical edges."),
                clEnumValN(FunctionSummary::FSHT_All, "all", "All edges.")));
 
+cl::opt<std::string> ModuleSummaryDotFile(
+    "module-summary-dot-file", cl::init(""), cl::Hidden,
+    cl::value_desc("filename"),
+    cl::desc("File to emit dot graph of new summary into."));
+
 // Walk through the operands of a given User via worklist iteration and populate
 // the set of GlobalValue references encountered. Invoked either on an
 // Instruction or a GlobalVariable (which walks its initializer).
@@ -625,6 +630,15 @@ ModuleSummaryIndex llvm::buildModuleSummaryIndex(
     }
   }
 
+  if (!ModuleSummaryDotFile.empty()) {
+    std::error_code EC;
+    raw_fd_ostream OSDot(ModuleSummaryDotFile, EC, sys::fs::OpenFlags::F_None);
+    if (EC)
+      report_fatal_error(Twine("Failed to open dot file ") +
+                         ModuleSummaryDotFile + ": " + EC.message() + "\n");
+    Index.exportToDot(OSDot);
+  }
+
   return Index;
 }