diff --git a/lib/Target/XCore/Disassembler/XCoreDisassembler.cpp b/lib/Target/XCore/Disassembler/XCoreDisassembler.cpp
index c995a9c3459..0bae15c0141 100644
--- a/lib/Target/XCore/Disassembler/XCoreDisassembler.cpp
+++ b/lib/Target/XCore/Disassembler/XCoreDisassembler.cpp
@@ -140,6 +140,11 @@ static DecodeStatus Decode3RInstruction(MCInst &Inst,
                                         uint64_t Address,
                                         const void *Decoder);
 
+static DecodeStatus Decode3RImmInstruction(MCInst &Inst,
+                                           unsigned Insn,
+                                           uint64_t Address,
+                                           const void *Decoder);
+
 static DecodeStatus Decode2RUSInstruction(MCInst &Inst,
                                           unsigned Insn,
                                           uint64_t Address,
@@ -313,6 +318,9 @@ Decode2OpInstructionFail(MCInst &Inst, unsigned Insn, uint64_t Address,
   case 0x16:
     Inst.setOpcode(XCore::EQ_2rus);
     return Decode2RUSInstruction(Inst, Insn, Address, Decoder);
+  case 0x17:
+    Inst.setOpcode(XCore::TSETR_3r);
+    return Decode3RImmInstruction(Inst, Insn, Address, Decoder);
   case 0x18:
     Inst.setOpcode(XCore::LSS_3r);
     return Decode3RInstruction(Inst, Insn, Address, Decoder);
@@ -515,6 +523,19 @@ Decode3RInstruction(MCInst &Inst, unsigned Insn, uint64_t Address,
   return S;
 }
 
+static DecodeStatus
+Decode3RImmInstruction(MCInst &Inst, unsigned Insn, uint64_t Address,
+                       const void *Decoder) {
+  unsigned Op1, Op2, Op3;
+  DecodeStatus S = Decode3OpInstruction(Insn, Op1, Op2, Op3);
+  if (S == MCDisassembler::Success) {
+    Inst.addOperand(MCOperand::CreateImm(Op1));
+    DecodeGRRegsRegisterClass(Inst, Op2, Address, Decoder);
+    DecodeGRRegsRegisterClass(Inst, Op3, Address, Decoder);
+  }
+  return S;
+}
+
 static DecodeStatus
 Decode2RUSInstruction(MCInst &Inst, unsigned Insn, uint64_t Address,
                       const void *Decoder) {
diff --git a/lib/Target/XCore/XCoreInstrFormats.td b/lib/Target/XCore/XCoreInstrFormats.td
index 8dceb30b0da..057721e4fa3 100644
--- a/lib/Target/XCore/XCoreInstrFormats.td
+++ b/lib/Target/XCore/XCoreInstrFormats.td
@@ -39,6 +39,14 @@ class _F3R<bits<5> opc, dag outs, dag ins, string asmstr, list<dag> pattern>
   let DecoderMethod = "Decode3RInstruction";
 }
 
+// 3R with first operand as an immediate. Used for TSETR where the first
+// operand is treated as an immediate since it refers to a register number in
+// another thread.
+class _F3RImm<bits<5> opc, dag outs, dag ins, string asmstr, list<dag> pattern>
+    : _F3R<opc, outs, ins, asmstr, pattern> {
+  let DecoderMethod = "Decode3RImmInstruction";
+}
+
 class _FL3R<bits<9> opc, dag outs, dag ins, string asmstr, list<dag> pattern>
     : InstXCore<4, outs, ins, asmstr, pattern> {
   let Inst{31-27} = opc{8-4};
diff --git a/lib/Target/XCore/XCoreInstrInfo.td b/lib/Target/XCore/XCoreInstrInfo.td
index 38e2fbc1db5..d3669195042 100644
--- a/lib/Target/XCore/XCoreInstrInfo.td
+++ b/lib/Target/XCore/XCoreInstrInfo.td
@@ -395,7 +395,11 @@ def STW_2rus : _F2RUS<0b0000, (outs),
 
 defm SHL : F3R_2RBITP<0b00100, 0b10100, "shl", shl>;
 defm SHR : F3R_2RBITP<0b00101, 0b10101, "shr", srl>;
-// TODO tsetr
+
+// The first operand is treated as an immediate since it refers to a register
+// number in another thread.
+def TSETR_3r : _F3RImm<0b10111, (outs), (ins i32imm:$a, GRRegs:$b, GRRegs:$c),
+                       "set t[$c]:r$a, $b", []>;
 
 // Three operand long
 def LDAWF_l3r : _FL3R<0b000111100, (outs GRRegs:$dst),
diff --git a/test/MC/Disassembler/XCore/xcore.txt b/test/MC/Disassembler/XCore/xcore.txt
index 52c20193885..132ae12fb5b 100644
--- a/test/MC/Disassembler/XCore/xcore.txt
+++ b/test/MC/Disassembler/XCore/xcore.txt
@@ -325,6 +325,9 @@
 # CHECK: sub r4, r2, r5
 0x89 0x1a
 
+# CHECK: set t[r0]:r1, r2
+0x18 0xb8
+
 # 2rus instructions
 
 # CHECK: add r10, r2, 5