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diff --git a/contrib/llvm-project/llvm/tools/opt/PrintSCC.cpp b/contrib/llvm-project/llvm/tools/opt/PrintSCC.cpp
new file mode 100644
index 000000000000..419886d6cc60
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+++ b/contrib/llvm-project/llvm/tools/opt/PrintSCC.cpp
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+//===- PrintSCC.cpp - Enumerate SCCs in some key graphs -------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file provides passes to print out SCCs in a CFG or a CallGraph.
+// Normally, you would not use these passes; instead, you would use the
+// scc_iterator directly to enumerate SCCs and process them in some way.  These
+// passes serve three purposes:
+//
+// (1) As a reference for how to use the scc_iterator.
+// (2) To print out the SCCs for a CFG or a CallGraph:
+//       analyze -print-cfg-sccs            to print the SCCs in each CFG of a module.
+//       analyze -print-cfg-sccs -stats     to print the #SCCs and the maximum SCC size.
+//       analyze -print-cfg-sccs -debug > /dev/null to watch the algorithm in action.
+//
+//     and similarly:
+//       analyze -print-callgraph-sccs [-stats] [-debug] to print SCCs in the CallGraph
+//
+// (3) To test the scc_iterator.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/ADT/SCCIterator.h"
+#include "llvm/Analysis/CallGraph.h"
+#include "llvm/IR/CFG.h"
+#include "llvm/IR/Module.h"
+#include "llvm/Pass.h"
+#include "llvm/Support/raw_ostream.h"
+using namespace llvm;
+
+namespace {
+  struct CFGSCC : public FunctionPass {
+    static char ID;  // Pass identification, replacement for typeid
+    CFGSCC() : FunctionPass(ID) {}
+    bool runOnFunction(Function& func) override;
+
+    void print(raw_ostream &O, const Module* = nullptr) const override { }
+
+    void getAnalysisUsage(AnalysisUsage &AU) const override {
+      AU.setPreservesAll();
+    }
+  };
+
+  struct CallGraphSCC : public ModulePass {
+    static char ID;  // Pass identification, replacement for typeid
+    CallGraphSCC() : ModulePass(ID) {}
+
+    // run - Print out SCCs in the call graph for the specified module.
+    bool runOnModule(Module &M) override;
+
+    void print(raw_ostream &O, const Module* = nullptr) const override { }
+
+    // getAnalysisUsage - This pass requires the CallGraph.
+    void getAnalysisUsage(AnalysisUsage &AU) const override {
+      AU.setPreservesAll();
+      AU.addRequired<CallGraphWrapperPass>();
+    }
+  };
+}
+
+char CFGSCC::ID = 0;
+static RegisterPass<CFGSCC>
+Y("print-cfg-sccs", "Print SCCs of each function CFG");
+
+char CallGraphSCC::ID = 0;
+static RegisterPass<CallGraphSCC>
+Z("print-callgraph-sccs", "Print SCCs of the Call Graph");
+
+bool CFGSCC::runOnFunction(Function &F) {
+  unsigned sccNum = 0;
+  errs() << "SCCs for Function " << F.getName() << " in PostOrder:";
+  for (scc_iterator<Function*> SCCI = scc_begin(&F); !SCCI.isAtEnd(); ++SCCI) {
+    const std::vector<BasicBlock *> &nextSCC = *SCCI;
+    errs() << "\nSCC #" << ++sccNum << " : ";
+    for (std::vector<BasicBlock*>::const_iterator I = nextSCC.begin(),
+           E = nextSCC.end(); I != E; ++I)
+      errs() << (*I)->getName() << ", ";
+    if (nextSCC.size() == 1 && SCCI.hasLoop())
+      errs() << " (Has self-loop).";
+  }
+  errs() << "\n";
+
+  return true;
+}
+
+
+// run - Print out SCCs in the call graph for the specified module.
+bool CallGraphSCC::runOnModule(Module &M) {
+  CallGraph &CG = getAnalysis<CallGraphWrapperPass>().getCallGraph();
+  unsigned sccNum = 0;
+  errs() << "SCCs for the program in PostOrder:";
+  for (scc_iterator<CallGraph*> SCCI = scc_begin(&CG); !SCCI.isAtEnd();
+       ++SCCI) {
+    const std::vector<CallGraphNode*> &nextSCC = *SCCI;
+    errs() << "\nSCC #" << ++sccNum << " : ";
+    for (std::vector<CallGraphNode*>::const_iterator I = nextSCC.begin(),
+           E = nextSCC.end(); I != E; ++I)
+      errs() << ((*I)->getFunction() ? (*I)->getFunction()->getName()
+                                     : "external node") << ", ";
+    if (nextSCC.size() == 1 && SCCI.hasLoop())
+      errs() << " (Has self-loop).";
+  }
+  errs() << "\n";
+
+  return true;
+}