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diff --git a/contrib/llvm/lib/CodeGen/ResetMachineFunctionPass.cpp b/contrib/llvm/lib/CodeGen/ResetMachineFunctionPass.cpp
new file mode 100644
index 0000000..4519641
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+++ b/contrib/llvm/lib/CodeGen/ResetMachineFunctionPass.cpp
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+//===-- ResetMachineFunctionPass.cpp - Reset Machine Function ----*- C++ -*-==//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+/// \file
+/// This file implements a pass that will conditionally reset a machine
+/// function as if it was just created. This is used to provide a fallback
+/// mechanism when GlobalISel fails, thus the condition for the reset to
+/// happen is that the MachineFunction has the FailedISel property.
+//===----------------------------------------------------------------------===//
+
+#include "llvm/ADT/Statistic.h"
+#include "llvm/CodeGen/Passes.h"
+#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/CodeGen/MachineFunctionPass.h"
+#include "llvm/IR/DiagnosticInfo.h"
+#include "llvm/Support/Debug.h"
+using namespace llvm;
+
+#define DEBUG_TYPE "reset-machine-function"
+
+STATISTIC(NumFunctionsReset, "Number of functions reset");
+
+namespace {
+  class ResetMachineFunction : public MachineFunctionPass {
+    /// Tells whether or not this pass should emit a fallback
+    /// diagnostic when it resets a function.
+    bool EmitFallbackDiag;
+
+  public:
+    static char ID; // Pass identification, replacement for typeid
+    ResetMachineFunction(bool EmitFallbackDiag = false)
+        : MachineFunctionPass(ID), EmitFallbackDiag(EmitFallbackDiag) {}
+
+    StringRef getPassName() const override { return "ResetMachineFunction"; }
+
+    bool runOnMachineFunction(MachineFunction &MF) override {
+      if (MF.getProperties().hasProperty(
+              MachineFunctionProperties::Property::FailedISel)) {
+        DEBUG(dbgs() << "Reseting: " << MF.getName() << '\n');
+        ++NumFunctionsReset;
+        MF.reset();
+        if (EmitFallbackDiag) {
+          const Function &F = *MF.getFunction();
+          DiagnosticInfoISelFallback DiagFallback(F);
+          F.getContext().diagnose(DiagFallback);
+        }
+        return true;
+      }
+      return false;
+    }
+
+  };
+} // end anonymous namespace
+
+char ResetMachineFunction::ID = 0;
+INITIALIZE_PASS(ResetMachineFunction, DEBUG_TYPE,
+                "reset machine function if ISel failed", false, false)
+
+MachineFunctionPass *
+llvm::createResetMachineFunctionPass(bool EmitFallbackDiag = false) {
+  return new ResetMachineFunction(EmitFallbackDiag);
+}