Index: lib/Target/Mips/AsmParser/MipsAsmParser.cpp
===================================================================
--- lib/Target/Mips/AsmParser/MipsAsmParser.cpp
+++ lib/Target/Mips/AsmParser/MipsAsmParser.cpp
@@ -210,6 +210,7 @@
   bool parseDirectiveNaN();
   bool parseDirectiveSet();
   bool parseDirectiveOption();
+  bool parseInsnDirective();
 
   bool parseSetAtDirective();
   bool parseSetNoAtDirective();
@@ -4039,6 +4040,22 @@
   return false;
 }
 
+/// parseInsnDirective
+///  ::= .insn
+bool MipsAsmParser::parseInsnDirective() {
+  // If this is not the end of the statement, report an error.
+  if (getLexer().isNot(AsmToken::EndOfStatement)) {
+    reportParseError("unexpected token, expected end of statement");
+    return false;
+  }
+
+  // The actual label marking happens in MipsELFStreamer::markLabelsAsMicroMips.
+  getTargetStreamer().emitDirectiveInsn();
+
+  getParser().Lex(); // Eat EndOfStatement token.
+  return false;
+}
+
 /// parseDirectiveModule
 ///  ::= .module oddspreg
 ///  ::= .module nooddspreg
@@ -4429,6 +4446,9 @@
   if (IDVal == ".module")
     return parseDirectiveModule();
 
+  if (IDVal == ".insn")
+    return parseInsnDirective();
+
   return true;
 }
 
Index: lib/Target/Mips/MCTargetDesc/MipsELFStreamer.h
===================================================================
--- lib/Target/Mips/MCTargetDesc/MipsELFStreamer.h
+++ lib/Target/Mips/MCTargetDesc/MipsELFStreamer.h
@@ -65,6 +65,9 @@
 
   /// Emits all the option records stored up until the point it's called.
   void EmitMipsOptionRecords();
+
+  /// Mark labels as microMIPS.
+  void markLabelsAsMicroMips();
 };
 
 MCELFStreamer *createMipsELFStreamer(MCContext &Context, MCAsmBackend &MAB,
Index: lib/Target/Mips/MCTargetDesc/MipsELFStreamer.cpp
===================================================================
--- lib/Target/Mips/MCTargetDesc/MipsELFStreamer.cpp
+++ lib/Target/Mips/MCTargetDesc/MipsELFStreamer.cpp
@@ -34,16 +34,20 @@
     RegInfoRecord->SetPhysRegUsed(Reg, MCRegInfo);
   }
 
-  if (ELFTargetStreamer->isMicroMipsEnabled()) {
-    for (auto Label : Labels) {
-      MCSymbolData &Data = getOrCreateSymbolData(Label);
-      // The "other" values are stored in the last 6 bits of the second byte.
-      // The traditional defines for STO values assume the full byte and thus
-      // the shift to pack it.
-      MCELF::setOther(Data, ELF::STO_MIPS_MICROMIPS >> 2);
-    }
-  }
+  if (ELFTargetStreamer->isMicroMipsEnabled())
+    markLabelsAsMicroMips();
+  else
+    Labels.clear();
+}
 
+void MipsELFStreamer::markLabelsAsMicroMips() {
+  for (auto Label : Labels) {
+    MCSymbolData &Data = getOrCreateSymbolData(Label);
+    // The "other" values are stored in the last 6 bits of the second byte.
+    // The traditional defines for STO values assume the full byte and thus
+    // the shift to pack it.
+    MCELF::setOther(Data, ELF::STO_MIPS_MICROMIPS >> 2);
+  }
   Labels.clear();
 }
 
Index: lib/Target/Mips/MCTargetDesc/MipsTargetStreamer.cpp
===================================================================
--- lib/Target/Mips/MCTargetDesc/MipsTargetStreamer.cpp
+++ lib/Target/Mips/MCTargetDesc/MipsTargetStreamer.cpp
@@ -54,6 +54,7 @@
 void MipsTargetStreamer::emitDirectiveNaNLegacy() {}
 void MipsTargetStreamer::emitDirectiveOptionPic0() {}
 void MipsTargetStreamer::emitDirectiveOptionPic2() {}
+void MipsTargetStreamer::emitDirectiveInsn() { forbidModuleDirective(); }
 void MipsTargetStreamer::emitFrame(unsigned StackReg, unsigned StackSize,
                                    unsigned ReturnReg) {}
 void MipsTargetStreamer::emitMask(unsigned CPUBitmask, int CPUTopSavedRegOff) {}
@@ -185,6 +186,11 @@
   OS << "\t.option\tpic2\n";
 }
 
+void MipsTargetAsmStreamer::emitDirectiveInsn() {
+  MipsTargetStreamer::emitDirectiveInsn();
+  OS << "\t.insn\n";
+}
+
 void MipsTargetAsmStreamer::emitFrame(unsigned StackReg, unsigned StackSize,
                                       unsigned ReturnReg) {
   OS << "\t.frame\t$"
@@ -629,6 +635,15 @@
   MCA.setELFHeaderEFlags(Flags);
 }
 
+void MipsTargetELFStreamer::emitDirectiveInsn() {
+  MipsTargetStreamer::emitDirectiveInsn();
+  // FIXME: Also mark labels when in MIPS16 mode.
+  if (isMicroMipsEnabled()) {
+    MipsELFStreamer &MEF = static_cast<MipsELFStreamer &>(Streamer);
+    MEF.markLabelsAsMicroMips();
+  }
+}
+
 void MipsTargetELFStreamer::emitFrame(unsigned StackReg, unsigned StackSize,
                                       unsigned ReturnReg_) {
   MCContext &Context = getStreamer().getAssembler().getContext();
Index: lib/Target/Mips/MipsTargetStreamer.h
===================================================================
--- lib/Target/Mips/MipsTargetStreamer.h
+++ lib/Target/Mips/MipsTargetStreamer.h
@@ -45,6 +45,7 @@
   virtual void emitDirectiveNaNLegacy();
   virtual void emitDirectiveOptionPic0();
   virtual void emitDirectiveOptionPic2();
+  virtual void emitDirectiveInsn();
   virtual void emitFrame(unsigned StackReg, unsigned StackSize,
                          unsigned ReturnReg);
   virtual void emitMask(unsigned CPUBitmask, int CPUTopSavedRegOff);
@@ -160,6 +161,7 @@
   void emitDirectiveNaNLegacy() override;
   void emitDirectiveOptionPic0() override;
   void emitDirectiveOptionPic2() override;
+  void emitDirectiveInsn() override;
   void emitFrame(unsigned StackReg, unsigned StackSize,
                  unsigned ReturnReg) override;
   void emitMask(unsigned CPUBitmask, int CPUTopSavedRegOff) override;
@@ -228,6 +230,7 @@
   void emitDirectiveNaNLegacy() override;
   void emitDirectiveOptionPic0() override;
   void emitDirectiveOptionPic2() override;
+  void emitDirectiveInsn() override;
   void emitFrame(unsigned StackReg, unsigned StackSize,
                  unsigned ReturnReg) override;
   void emitMask(unsigned CPUBitmask, int CPUTopSavedRegOff) override;
Index: test/MC/Mips/insn-directive.s
===================================================================
--- /dev/null
+++ test/MC/Mips/insn-directive.s
@@ -0,0 +1,84 @@
+# RUN: llvm-mc %s -arch=mips -mcpu=mips32 | FileCheck %s --check-prefix=ASM
+
+# RUN: llvm-mc %s -arch=mips -mcpu=mips32 -filetype=obj -o - | \
+# RUN:   llvm-readobj -symbols - | FileCheck %s --check-prefix=OBJ
+
+  .set micromips
+
+  .global f_mm_insn_data
+  .type f_mm_insn_data, @function
+f_mm_insn_data:
+  .insn
+  .word 0x00e73910   # add $7, $7, $7
+
+  .global f_mm_insn_instr
+  .type f_mm_insn_instr, @function
+f_mm_insn_instr:
+  .insn
+  add $7, $7, $7
+
+  .global o_mm_insn_data
+  .type o_mm_insn_data, @object
+o_mm_insn_data:
+  .insn
+  .word 0x00e73910   # add $7, $7, $7
+
+  .global o_mm_insn_instr
+  .type o_mm_insn_instr, @object
+o_mm_insn_instr:
+  .insn
+  add $7, $7, $7
+
+  .set nomicromips
+
+  .global f_normal_insn_data
+  .type f_normal_insn_data, @function
+f_normal_insn_data:
+  .insn
+  .word 0x00e73820   # add $7, $7, $7
+
+  .global f_normal_insn_instr
+  .type f_normal_insn_instr, @function
+f_normal_insn_instr:
+  .insn
+  add $7, $7, $7
+
+  .global o_normal_insn_data
+  .type o_normal_insn_data, @object
+o_normal_insn_data:
+  .insn
+  .word 0x00e73820   # add $7, $7, $7
+
+  .global o_normal_insn_instr
+  .type o_normal_insn_instr, @object
+o_normal_insn_instr:
+  .insn
+  add $7, $7, $7
+
+# ASM: .insn
+
+# OBJ: Symbols [
+# OBJ: Name: f_mm_insn_data
+# OBJ: Other: 128
+
+# OBJ: Name: f_mm_insn_instr
+# OBJ: Other: 128
+
+# OBJ: Name: f_normal_insn_data
+# OBJ: Other: 0
+
+# OBJ: Name: f_normal_insn_instr
+# OBJ: Other: 0
+
+# OBJ: Name: o_mm_insn_data
+# OBJ: Other: 128
+
+# OBJ: Name: o_mm_insn_instr
+# OBJ: Other: 128
+
+# OBJ: Name: o_normal_insn_data
+# OBJ: Other: 0
+
+# OBJ: Name: o_normal_insn_instr
+# OBJ: Other: 0
+# OBJ: ]