Index: include/llvm/CodeGen/TargetInstrInfo.h
===================================================================
--- include/llvm/CodeGen/TargetInstrInfo.h
+++ include/llvm/CodeGen/TargetInstrInfo.h
@@ -1602,9 +1602,6 @@
     return false;
   }
 
-  /// Returns true if the target implements the MachineOutliner.
-  virtual bool useMachineOutliner() const { return false; }
-
   /// Returns a \p outliner::TargetCostInfo struct containing target-specific
   /// information for a set of outlining candidates.
   virtual outliner::TargetCostInfo getOutlininingCandidateInfo(
Index: include/llvm/Target/TargetMachine.h
===================================================================
--- include/llvm/Target/TargetMachine.h
+++ include/llvm/Target/TargetMachine.h
@@ -202,6 +202,9 @@
   bool getO0WantsFastISel() { return O0WantsFastISel; }
   void setO0WantsFastISel(bool Enable) { O0WantsFastISel = Enable; }
   void setGlobalISel(bool Enable) { Options.EnableGlobalISel = Enable; }
+  void setMachineOutliner(bool Enable) {
+    Options.EnableMachineOutliner = Enable;
+  }
 
   bool shouldPrintMachineCode() const { return Options.PrintMachineCode; }
 
Index: include/llvm/Target/TargetOptions.h
===================================================================
--- include/llvm/Target/TargetOptions.h
+++ include/llvm/Target/TargetOptions.h
@@ -109,7 +109,8 @@
           FunctionSections(false), DataSections(false),
           UniqueSectionNames(true), TrapUnreachable(false),
           EmulatedTLS(false), ExplicitEmulatedTLS(false),
-          EnableIPRA(false), EmitStackSizeSection(false) {}
+          EnableIPRA(false), EmitStackSizeSection(false),
+          EnableMachineOutliner(false) {}
 
     /// PrintMachineCode - This flag is enabled when the -print-machineinstrs
     /// option is specified on the command line, and should enable debugging
@@ -226,6 +227,9 @@
     /// Emit section containing metadata on function stack sizes.
     unsigned EmitStackSizeSection : 1;
 
+    /// Enables the MachineOutliner pass.
+    unsigned EnableMachineOutliner : 1;
+
     /// FloatABIType - This setting is set by -float-abi=xxx option is specfied
     /// on the command line. This setting may either be Default, Soft, or Hard.
     /// Default selects the target's default behavior. Soft selects the ABI for
Index: lib/CodeGen/MachineOutliner.cpp
===================================================================
--- lib/CodeGen/MachineOutliner.cpp
+++ lib/CodeGen/MachineOutliner.cpp
@@ -1331,15 +1331,6 @@
   const TargetRegisterInfo *TRI = STI.getRegisterInfo();
   const TargetInstrInfo *TII = STI.getInstrInfo();
 
-  // Does the target implement the MachineOutliner? If it doesn't, quit here.
-  if (!TII->useMachineOutliner()) {
-    // No. So we're done.
-    LLVM_DEBUG(
-        dbgs()
-        << "Skipping pass: Target does not support the MachineOutliner.\n");
-    return false;
-  }
-
   // If the user specifies that they want to outline from linkonceodrs, set
   // it here.
   OutlineFromLinkOnceODRs = EnableLinkOnceODROutlining;
Index: lib/CodeGen/TargetPassConfig.cpp
===================================================================
--- lib/CodeGen/TargetPassConfig.cpp
+++ lib/CodeGen/TargetPassConfig.cpp
@@ -914,7 +914,9 @@
   addPass(&XRayInstrumentationID, false);
   addPass(&PatchableFunctionID, false);
 
-  if (EnableMachineOutliner == AlwaysOutline)
+  if (TM->Options.EnableMachineOutliner &&
+      getOptLevel() != CodeGenOpt::None &&
+      EnableMachineOutliner == AlwaysOutline)
     addPass(createMachineOutlinerPass());
 
   // Add passes that directly emit MI after all other MI passes.
Index: lib/Target/AArch64/AArch64InstrInfo.h
===================================================================
--- lib/Target/AArch64/AArch64InstrInfo.h
+++ lib/Target/AArch64/AArch64InstrInfo.h
@@ -236,8 +236,6 @@
   ArrayRef<std::pair<MachineMemOperand::Flags, const char *>>
   getSerializableMachineMemOperandTargetFlags() const override;
 
-  /// AArch64 supports the MachineOutliner.
-  bool useMachineOutliner() const override { return true; }
   bool isFunctionSafeToOutlineFrom(MachineFunction &MF,
                                    bool OutlineFromLinkOnceODRs) const override;
   outliner::TargetCostInfo getOutlininingCandidateInfo(
Index: lib/Target/AArch64/AArch64TargetMachine.cpp
===================================================================
--- lib/Target/AArch64/AArch64TargetMachine.cpp
+++ lib/Target/AArch64/AArch64TargetMachine.cpp
@@ -250,6 +250,9 @@
   // Enable GlobalISel at or below EnableGlobalISelAt0.
   if (getOptLevel() <= EnableGlobalISelAtO)
     setGlobalISel(true);
+
+  // AArch64 supports the MachineOutliner.
+  setMachineOutliner(true);
 }
 
 AArch64TargetMachine::~AArch64TargetMachine() = default;
Index: lib/Target/X86/X86InstrInfo.h
===================================================================
--- lib/Target/X86/X86InstrInfo.h
+++ lib/Target/X86/X86InstrInfo.h
@@ -553,9 +553,6 @@
   ArrayRef<std::pair<unsigned, const char *>>
   getSerializableDirectMachineOperandTargetFlags() const override;
 
-  /// X86 supports the MachineOutliner.
-  bool useMachineOutliner() const override { return true; }
-
   virtual outliner::TargetCostInfo getOutlininingCandidateInfo(
       std::vector<outliner::Candidate> &RepeatedSequenceLocs) const override;
 
Index: lib/Target/X86/X86TargetMachine.cpp
===================================================================
--- lib/Target/X86/X86TargetMachine.cpp
+++ lib/Target/X86/X86TargetMachine.cpp
@@ -232,6 +232,10 @@
       TT.isOSBinFormatMachO())
     this->Options.TrapUnreachable = true;
 
+  // Outlining is available for x86-64.
+  if (TT.getArch() == Triple::x86_64)
+    setMachineOutliner(true);
+
   initAsmInfo();
 }