Index: lib/Target/Mips/Disassembler/MipsDisassembler.cpp
===================================================================
--- lib/Target/Mips/Disassembler/MipsDisassembler.cpp
+++ lib/Target/Mips/Disassembler/MipsDisassembler.cpp
@@ -310,6 +310,15 @@
 static DecodeStatus DecodeSimm18Lsl3(MCInst &Inst, unsigned Insn,
                                      uint64_t Address, const void *Decoder);
 
+static DecodeStatus DecodeSimm9SP(MCInst &Inst, unsigned Insn,
+                                  uint64_t Address, const void *Decoder);
+
+static DecodeStatus DecodeANDI16Imm(MCInst &Inst, unsigned Insn,
+                                    uint64_t Address, const void *Decoder);
+
+static DecodeStatus DecodeUImm5lsl2(MCInst &Inst, unsigned Insn,
+                                   uint64_t Address, const void *Decoder);
+
 /// INSVE_[BHWD] have an implicit operand that the generated decoder doesn't
 /// handle.
 template <typename InsnType>
@@ -1446,6 +1455,36 @@
   return MCDisassembler::Success;
 }
 
+static DecodeStatus DecodeSimm9SP(MCInst &Inst, unsigned Insn,
+                                  uint64_t Address, const void *Decoder) {
+  int32_t DecodedValue;
+  switch (Insn) {
+  case 0: DecodedValue = SignExtend32<16>(0x100); break;
+  case 1: DecodedValue = SignExtend32<16>(0x101); break;
+  case 510: DecodedValue = SignExtend32<16>(0xfefe); break;
+  case 511: DecodedValue = SignExtend32<16>(0xfeff); break;
+  default: DecodedValue = SignExtend32<9>(Insn); break;
+  }
+  Inst.addOperand(MCOperand::CreateImm(DecodedValue << 2));
+  return MCDisassembler::Success;
+}
+
+static DecodeStatus DecodeANDI16Imm(MCInst &Inst, unsigned Insn,
+                                    uint64_t Address, const void *Decoder) {
+  // Insn must be >= 0, since it is unsigned that condition is always true.
+  assert(Insn < 16);
+  int32_t DecodedValues[] = {128, 1, 2, 3, 4, 7, 8, 15, 16, 31, 32, 63, 64,
+                             255, 32768, 65535};
+  Inst.addOperand(MCOperand::CreateImm(DecodedValues[Insn]));
+  return MCDisassembler::Success;
+}
+
+static DecodeStatus DecodeUImm5lsl2(MCInst &Inst, unsigned Insn,
+                                    uint64_t Address, const void *Decoder) {
+  Inst.addOperand(MCOperand::CreateImm(Insn << 2));
+  return MCDisassembler::Success;
+}
+
 static DecodeStatus DecodeRegListOperand(MCInst &Inst,
                                          unsigned Insn,
                                          uint64_t Address,
Index: lib/Target/Mips/MicroMipsInstrInfo.td
===================================================================
--- lib/Target/Mips/MicroMipsInstrInfo.td
+++ lib/Target/Mips/MicroMipsInstrInfo.td
@@ -9,6 +9,7 @@
 
 def uimm5_lsl2 : Operand<OtherVT> {
   let EncoderMethod = "getUImm5Lsl2Encoding";
+  let DecoderMethod = "DecodeUImm5lsl2";
 }
 
 def uimm6_lsl2 : Operand<i32> {
@@ -17,6 +18,7 @@
 
 def simm9_addiusp : Operand<i32> {
   let EncoderMethod = "getSImm9AddiuspValue";
+  let DecoderMethod = "DecodeSimm9SP";
 }
 
 def uimm3_shift : Operand<i32> {
@@ -29,6 +31,7 @@
 
 def uimm4_andi : Operand<i32> {
   let EncoderMethod = "getUImm4AndValue";
+  let DecoderMethod = "DecodeANDI16Imm";
 }
 
 def immSExtAddiur2 : ImmLeaf<i32, [{return Imm == 1 || Imm == -1 ||
Index: test/MC/Disassembler/Mips/micromips.txt
===================================================================
--- test/MC/Disassembler/Mips/micromips.txt
+++ test/MC/Disassembler/Mips/micromips.txt
@@ -16,6 +16,21 @@
 # CHECK: addiu $9, $6, -15001
 0x31 0x26 0xc5 0x67
 
+# CHECK: addiusp -16
+0x4f 0xf9
+
+# CHECK: addiusp -1028
+0x4f 0xff
+
+# CHECK: addiusp -1032
+0x4f 0xfd
+
+# CHECK: addiusp 1024
+0x4c 0x01
+
+# CHECK: addiusp 1028
+0x4c 0x03
+
 # CHECK: addu $9, $6, $7
 0x00 0xe6 0x49 0x50
 
@@ -61,6 +76,9 @@
 # CHECK: andi $9, $6, 17767
 0xd1 0x26 0x45 0x67
 
+# CHECK: andi16 $16, $2, 31
+0x2c 0x29
+
 # CHECK: or $3, $4, $5
 0x00 0xa4 0x1a 0x90
 
@@ -229,6 +247,9 @@
 # CHECK: jr $7
 0x00 0x07 0x0f 0x3c
 
+# CHECK: jraddiusp 20
+0x47 0x05
+
 # CHECK: beq $9, $6, 1332
 0x94 0xc9 0x02 0x9a
 
Index: test/MC/Disassembler/Mips/micromips_le.txt
===================================================================
--- test/MC/Disassembler/Mips/micromips_le.txt
+++ test/MC/Disassembler/Mips/micromips_le.txt
@@ -16,9 +16,27 @@
 # CHECK: addiu $9, $6, -15001
 0x26 0x31 0x67 0xc5
 
+# CHECK: addiusp -16
+0xf9 0x4f
+
+# CHECK: addiusp -1028
+0xff 0x4f
+
+# CHECK: addiusp -1032
+0xfd 0x4f
+
+# CHECK: addiusp 1024
+0x01 0x4c
+
+# CHECK: addiusp 1028
+0x03 0x4c
+
 # CHECK: addu $9, $6, $7
 0xe6 0x00 0x50 0x49
 
+# CHECK: andi16 $16, $2, 31
+0x29 0x2c
+
 # CHECK: sub $9, $6, $7
 0xe6 0x00 0x90 0x49
 
@@ -229,6 +247,9 @@
 # CHECK: jr $7
 0x07 0x00 0x3c 0x0f
 
+# CHECK: jraddiusp 20
+0x05 0x47
+
 # CHECK: beq $9, $6, 1332
 0xc9 0x94 0x9a 0x02
 
Index: test/MC/Mips/micromips-16-bit-instructions.s
===================================================================
--- test/MC/Mips/micromips-16-bit-instructions.s
+++ test/MC/Mips/micromips-16-bit-instructions.s
@@ -31,6 +31,10 @@
 # CHECK-EL: addiur2 $6, $7, -1      # encoding: [0x7e,0x6f]
 # CHECK-EL: addiur2 $6, $7, 12      # encoding: [0x76,0x6f]
 # CHECK-EL: addius5 $7, -2          # encoding: [0xfc,0x4c]
+# CHECK-EL: addiusp -1028           # encoding: [0xff,0x4f]
+# CHECK-EL: addiusp -1032           # encoding: [0xfd,0x4f]
+# CHECK-EL: addiusp 1024            # encoding: [0x01,0x4c]
+# CHECK-EL: addiusp 1028            # encoding: [0x03,0x4c]
 # CHECK-EL: addiusp -16             # encoding: [0xf9,0x4f]
 # CHECK-EL: mfhi    $9              # encoding: [0x09,0x46]
 # CHECK-EL: mflo    $9              # encoding: [0x49,0x46]
@@ -67,6 +71,10 @@
 # CHECK-EB: addiur2 $6, $7, -1      # encoding: [0x6f,0x7e]
 # CHECK-EB: addiur2 $6, $7, 12      # encoding: [0x6f,0x76]
 # CHECK-EB: addius5 $7, -2          # encoding: [0x4c,0xfc]
+# CHECK-EB: addiusp -1028           # encoding: [0x4f,0xff]
+# CHECK-EB: addiusp -1032           # encoding: [0x4f,0xfd]
+# CHECK-EB: addiusp 1024            # encoding: [0x4c,0x01]
+# CHECK-EB: addiusp 1028            # encoding: [0x4c,0x03]
 # CHECK-EB: addiusp -16             # encoding: [0x4f,0xf9]
 # CHECK-EB: mfhi    $9              # encoding: [0x46,0x09]
 # CHECK-EB: mflo    $9              # encoding: [0x46,0x49]
@@ -101,6 +109,10 @@
     addiur2 $6, $7, -1
     addiur2 $6, $7, 12
     addius5 $7, -2
+    addiusp -1028
+    addiusp -1032
+    addiusp 1024
+    addiusp 1028
     addiusp -16
     mfhi    $9
     mflo    $9