Index: llvm/trunk/lib/Target/Mips/AsmParser/MipsAsmParser.cpp
===================================================================
--- llvm/trunk/lib/Target/Mips/AsmParser/MipsAsmParser.cpp
+++ llvm/trunk/lib/Target/Mips/AsmParser/MipsAsmParser.cpp
@@ -343,6 +343,8 @@
   bool parseSetPushDirective();
   bool parseSetSoftFloatDirective();
   bool parseSetHardFloatDirective();
+  bool parseSetMtDirective();
+  bool parseSetNoMtDirective();
 
   bool parseSetAssignment();
 
@@ -6333,6 +6335,39 @@
   return false;
 }
 
+bool MipsAsmParser::parseSetMtDirective() {
+  MCAsmParser &Parser = getParser();
+  Parser.Lex(); // Eat "mt".
+
+  // 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;
+  }
+
+  setFeatureBits(Mips::FeatureMT, "mt");
+  getTargetStreamer().emitDirectiveSetMt();
+  Parser.Lex(); // Consume the EndOfStatement.
+  return false;
+}
+
+bool MipsAsmParser::parseSetNoMtDirective() {
+  MCAsmParser &Parser = getParser();
+  Parser.Lex(); // Eat "nomt".
+
+  // 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;
+  }
+
+  clearFeatureBits(Mips::FeatureMT, "mt");
+
+  getTargetStreamer().emitDirectiveSetNoMt();
+  Parser.Lex(); // Consume the EndOfStatement.
+  return false;
+}
+
 bool MipsAsmParser::parseSetPopDirective() {
   MCAsmParser &Parser = getParser();
   SMLoc Loc = getLexer().getLoc();
@@ -6833,6 +6868,10 @@
     return parseSetMsaDirective();
   } else if (Tok.getString() == "nomsa") {
     return parseSetNoMsaDirective();
+  } else if (Tok.getString() == "mt") {
+    return parseSetMtDirective();
+  } else if (Tok.getString() == "nomt") {
+    return parseSetNoMtDirective();
   } else if (Tok.getString() == "softfloat") {
     return parseSetSoftFloatDirective();
   } else if (Tok.getString() == "hardfloat") {
@@ -7082,6 +7121,7 @@
 ///  ::= .module fp=value
 ///  ::= .module softfloat
 ///  ::= .module hardfloat
+///  ::= .module mt
 bool MipsAsmParser::parseDirectiveModule() {
   MCAsmParser &Parser = getParser();
   MCAsmLexer &Lexer = getLexer();
@@ -7181,6 +7221,25 @@
     }
 
     return false; // parseDirectiveModule has finished successfully.
+  } else if (Option == "mt") {
+    setModuleFeatureBits(Mips::FeatureMT, "mt");
+
+    // Synchronize the ABI Flags information with the FeatureBits information we
+    // updated above.
+    getTargetStreamer().updateABIInfo(*this);
+
+    // If priniing assembly, use the recently updated ABI Flags information.
+    // If generating ELF, don't do anything (the .MIPS.abiflags section gets
+    // emitted later).
+    getTargetStreamer().emitDirectiveModuleMT();
+
+    // 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;
+    }
+
+    return false; // parseDirectiveModule has finished successfully.
   } else {
     return Error(L, "'" + Twine(Option) + "' is not a valid .module option.");
   }
Index: llvm/trunk/lib/Target/Mips/MCTargetDesc/MipsTargetStreamer.cpp
===================================================================
--- llvm/trunk/lib/Target/Mips/MCTargetDesc/MipsTargetStreamer.cpp
+++ llvm/trunk/lib/Target/Mips/MCTargetDesc/MipsTargetStreamer.cpp
@@ -50,6 +50,8 @@
 void MipsTargetStreamer::emitDirectiveSetNoMacro() { forbidModuleDirective(); }
 void MipsTargetStreamer::emitDirectiveSetMsa() { forbidModuleDirective(); }
 void MipsTargetStreamer::emitDirectiveSetNoMsa() { forbidModuleDirective(); }
+void MipsTargetStreamer::emitDirectiveSetMt() {}
+void MipsTargetStreamer::emitDirectiveSetNoMt() { forbidModuleDirective(); }
 void MipsTargetStreamer::emitDirectiveSetAt() { forbidModuleDirective(); }
 void MipsTargetStreamer::emitDirectiveSetAtWithArg(unsigned RegNo) {
   forbidModuleDirective();
@@ -118,6 +120,7 @@
 }
 void MipsTargetStreamer::emitDirectiveModuleSoftFloat() {}
 void MipsTargetStreamer::emitDirectiveModuleHardFloat() {}
+void MipsTargetStreamer::emitDirectiveModuleMT() {}
 void MipsTargetStreamer::emitDirectiveSetFp(
     MipsABIFlagsSection::FpABIKind Value) {
   forbidModuleDirective();
@@ -392,6 +395,16 @@
   MipsTargetStreamer::emitDirectiveSetNoMsa();
 }
 
+void MipsTargetAsmStreamer::emitDirectiveSetMt() {
+  OS << "\t.set\tmt\n";
+  MipsTargetStreamer::emitDirectiveSetMt();
+}
+
+void MipsTargetAsmStreamer::emitDirectiveSetNoMt() {
+  OS << "\t.set\tnomt\n";
+  MipsTargetStreamer::emitDirectiveSetNoMt();
+}
+
 void MipsTargetAsmStreamer::emitDirectiveSetAt() {
   OS << "\t.set\tat\n";
   MipsTargetStreamer::emitDirectiveSetAt();
@@ -656,6 +669,10 @@
   OS << "\t.module\thardfloat\n";
 }
 
+void MipsTargetAsmStreamer::emitDirectiveModuleMT() {
+  OS << "\t.module\tmt\n";
+}
+
 // This part is for ELF object output.
 MipsTargetELFStreamer::MipsTargetELFStreamer(MCStreamer &S,
                                              const MCSubtargetInfo &STI)
Index: llvm/trunk/lib/Target/Mips/MipsTargetStreamer.h
===================================================================
--- llvm/trunk/lib/Target/Mips/MipsTargetStreamer.h
+++ llvm/trunk/lib/Target/Mips/MipsTargetStreamer.h
@@ -40,6 +40,8 @@
   virtual void emitDirectiveSetNoMacro();
   virtual void emitDirectiveSetMsa();
   virtual void emitDirectiveSetNoMsa();
+  virtual void emitDirectiveSetMt();
+  virtual void emitDirectiveSetNoMt();
   virtual void emitDirectiveSetAt();
   virtual void emitDirectiveSetAtWithArg(unsigned RegNo);
   virtual void emitDirectiveSetNoAt();
@@ -96,6 +98,7 @@
   virtual void emitDirectiveModuleOddSPReg();
   virtual void emitDirectiveModuleSoftFloat();
   virtual void emitDirectiveModuleHardFloat();
+  virtual void emitDirectiveModuleMT();
   virtual void emitDirectiveSetFp(MipsABIFlagsSection::FpABIKind Value);
   virtual void emitDirectiveSetOddSPReg();
   virtual void emitDirectiveSetNoOddSPReg();
@@ -204,6 +207,8 @@
   void emitDirectiveSetNoMacro() override;
   void emitDirectiveSetMsa() override;
   void emitDirectiveSetNoMsa() override;
+  void emitDirectiveSetMt() override;
+  void emitDirectiveSetNoMt() override;
   void emitDirectiveSetAt() override;
   void emitDirectiveSetAtWithArg(unsigned RegNo) override;
   void emitDirectiveSetNoAt() override;
@@ -267,6 +272,7 @@
   void emitDirectiveModuleOddSPReg() override;
   void emitDirectiveModuleSoftFloat() override;
   void emitDirectiveModuleHardFloat() override;
+  void emitDirectiveModuleMT() override;
   void emitDirectiveSetFp(MipsABIFlagsSection::FpABIKind Value) override;
   void emitDirectiveSetOddSPReg() override;
   void emitDirectiveSetNoOddSPReg() override;
Index: llvm/trunk/test/MC/Mips/mt/module-directive-invalid.s
===================================================================
--- llvm/trunk/test/MC/Mips/mt/module-directive-invalid.s
+++ llvm/trunk/test/MC/Mips/mt/module-directive-invalid.s
@@ -0,0 +1,6 @@
+# RUN: not llvm-mc -arch=mips -mcpu=mips32r5 < %s 2>&1 | FileCheck %s
+
+# CHECK: error: .module directive must appear before any code
+  .set  nomips16
+  .module mt
+  nop
Index: llvm/trunk/test/MC/Mips/mt/module-directive.s
===================================================================
--- llvm/trunk/test/MC/Mips/mt/module-directive.s
+++ llvm/trunk/test/MC/Mips/mt/module-directive.s
@@ -0,0 +1,16 @@
+# RUN: llvm-mc < %s -arch=mips -mcpu=mips32r2 -filetype=obj -o - | \
+# RUN:   llvm-readobj -mips-abi-flags | FileCheck --check-prefix=CHECK-OBJ %s
+# RUN: llvm-mc < %s -arch=mips -mcpu=mips32r2 -filetype=asm -o - | \
+# RUN:   FileCheck --check-prefix=CHECK-ASM %s
+
+# Test that the .module directive sets the MT flag in .MIPS.abiflags when
+# assembling to boject files.
+
+# Test that the .moodule directive is re-emitted when expanding assembly.
+
+# CHECK-OBJ: ASEs
+# CHECK-OBJ-NEXT: MT (0x40)
+
+# CHECK-ASM:  .module mt
+.module mt
+nop
Index: llvm/trunk/test/MC/Mips/mt/set-directive.s
===================================================================
--- llvm/trunk/test/MC/Mips/mt/set-directive.s
+++ llvm/trunk/test/MC/Mips/mt/set-directive.s
@@ -0,0 +1,14 @@
+# RUN: llvm-mc < %s -arch=mips -mcpu=mips32r2 -filetype=obj -o - | \
+# RUN:   llvm-readobj -mips-abi-flags | FileCheck %s --check-prefix=CHECK-OBJ
+# RUN: llvm-mc < %s -arch=mips -mcpu=mips32r2 -filetype=asm -o - | \
+# RUN:   FileCheck %s --check-prefix=CHECK-ASM
+
+# Test that the MT ASE flag in .MIPS.abiflags is _not_ set by .set.
+# Test that '.set mt' is emitted by the asm target streamer.
+
+# CHECK-OBJ: ASEs
+# CHECK-OBJ-NOT: MT (0x40)
+
+# CHECK-ASM: .set mt
+  .set  mt
+  nop