[mips][microMIPS] Implement MTC*, MTHC* and DMTC* instructions

[hvarga]

Summary

This patch implements microMIPSr6 MTC0, MTC1, MTC2, MTHC0, MTHC1, MTHC2, DMTC0, DMTC1, DMTC2 instructions.

[hvarga]

Fixed typo in instruction encoding in lib/Target/Mips/MicroMips64r6InstrInfo.td for dmtc1 and dmtc2.

[sdardis]

I believe the changes to test/MC/Mips/{mips32r5mips32r6,mips64r5,mips64r6}/invalid.s while welcome are unnecessary given that this patch deals with microMIPSR6. Those should be split out as a separate patch.

I've noticed a possible error in the documentation that shows dmtc2 as syntactically taking a selector but having no field for encoding it in the binary instruction. In contrast mtc2 and mthc2 do not syntactically have a selector. I'm awaiting clarification on that issue.

Thanks,
Simon

lib/Target/Mips/MicroMips32r6InstrInfo.td

556

Space after "NoItinerary,"

test/MC/Disassembler/Mips/micromips32r6/valid.txt

266

Missing instruction on the last line. I presume it's mthc2.

Also can you add the cases with no selector, i.e. "mtc0 $5, $9", "mthc0 $5, $9".

test/MC/Disassembler/Mips/micromips64r6/valid.txt

172

No selector case here too.

Also can you add the mt* cases as well here.

test/MC/Mips/micromips64r6/invalid.s

134

Add mtc0, mthc0 cases here.

test/MC/Mips/micromips64r6/valid.s

157

Can you add the mt* cases here too?

[dsanders]

In addition to Simon's comments ...

lib/Target/Mips/MicroMips32r6InstrInfo.td

580–581

As with the MFHC1 patch, we need a 64-bit FPU version of MTHC1.

[sdardis]

Instructions that access coprocessor 2 don't have a selector. The Impl field should be treated as a 5 bit register field for consistency with binutils.

[hvarga]

Patch modified according to comments.

[dsanders]

Instructions that access coprocessor 2 don't have a selector. The Impl field should be treated as a 5 bit register field for consistency with binutils.

I'm surprised by this but it's correct. It's worth mentioning that this only applies to microMIPS though. The assembler has traditionally accepted a sel operand for the other ISA's.

[sdardis]

LGTM.

lib/Target/Mips/MicroMips32r6InstrFormats.td

class POOL32F_CLASS_FM_MMR6<string instr_asm, bits<2> fmt, bits<9> funct>
 
   let Inst{31-26} = 0b010101;
   let Inst{25-21} = fs;
   let Inst{20-16} = fd;
   let Inst{15-11} = 0b00000;
   let Inst{10-9}  = fmt;
   let Inst{8-0}   = funct;
 }
+
+class POOL32A_MFTC0_FM_MMR6<string instr_asm, bits<5> funct, bits<6> opcode>
+    : MMR6Arch<instr_asm>, MipsR6Inst {
+  bits<5> rt;
+  bits<5> rs;
+  bits<3> sel;
+
+  bits<32> Inst;
+
+  let Inst{31-26} = 0b000000;
+  let Inst{25-21} = rt;
+  let Inst{20-16} = rs;
+  let Inst{15-14} = 0;
+  let Inst{13-11} = sel;
+  let Inst{10-6}  = funct;
+  let Inst{5-0}   = opcode;
+}
+
+class POOL32F_MFTC1_FM_MMR6<string instr_asm, bits<8> funct>
+    : MMR6Arch<instr_asm>, MipsR6Inst {
+  bits<5> rt;
+  bits<5> fs;
+
+  bits<32> Inst;
+
+  let Inst{31-26} = 0b010101;
+  let Inst{25-21} = rt;
+  let Inst{20-16} = fs;
+  let Inst{15-14} = 0;
+  let Inst{13-6}  = funct;
+  let Inst{5-0}   = 0b111011;
+}
+
+class POOL32A_MFTC2_FM_MMR6<string instr_asm, bits<10> funct>
+    : MMR6Arch<instr_asm>, MipsR6Inst {
+  bits<5> rt;
+  bits<5> impl;
+
+  bits<32> Inst;
+
+  let Inst{31-26} = 0b000000;
+  let Inst{25-21} = rt;
+  let Inst{20-16} = impl;
+  let Inst{15-6}  = funct;
+  let Inst{5-0}   = 0b111100;
+}

lib/Target/Mips/MicroMips32r6InstrInfo.td

 class LWPC_MMR6_ENC  : PCREL19_FM_MMR6<0b01>;
 class LWM16_MMR6_ENC : POOL16C_LWM_SWM_FM_MM16R6<0x2>;
 class MOD_MMR6_ENC : ARITH_FM_MMR6<"mod", 0x158>;
 class MODU_MMR6_ENC : ARITH_FM_MMR6<"modu", 0x1d8>;
 class MUL_MMR6_ENC : ARITH_FM_MMR6<"mul", 0x18>;
 class MUH_MMR6_ENC : ARITH_FM_MMR6<"muh", 0x58>;
 class MULU_MMR6_ENC : ARITH_FM_MMR6<"mulu", 0x98>;
 class MUHU_MMR6_ENC : ARITH_FM_MMR6<"muhu", 0xd8>;
+class MTC0_MMR6_ENC : POOL32A_MFTC0_FM_MMR6<"mtc0", 0b01011, 0b111100>;
+class MTC1_MMR6_ENC : POOL32F_MFTC1_FM_MMR6<"mtc1", 0b10100000>;
+class MTC2_MMR6_ENC : POOL32A_MFTC2_FM_MMR6<"mtc2", 0b0101110100>;
+class MTHC0_MMR6_ENC : POOL32A_MFTC0_FM_MMR6<"mthc0", 0b01011, 0b110100>;
+class MTHC1_MMR6_ENC : POOL32F_MFTC1_FM_MMR6<"mthc1", 0b11100000>;
+class MTHC2_MMR6_ENC : POOL32A_MFTC2_FM_MMR6<"mthc2", 0b1001110100>;
 class NOR_MMR6_ENC : ARITH_FM_MMR6<"nor", 0x2d0>;
 class OR_MMR6_ENC : ARITH_FM_MMR6<"or", 0x290>;
 class ORI_MMR6_ENC : ADDI_FM_MMR6<"ori", 0x14>;
 class PREF_MMR6_ENC : CACHE_PREF_FM_MMR6<0b011000, 0b0010>;
 class SB16_MMR6_ENC : LOAD_STORE_FM_MM16<0x22>;
 class SEB_MMR6_ENC : SIGN_EXTEND_FM_MMR6<"seb", 0b0010101100>;
 class SEH_MMR6_ENC : SIGN_EXTEND_FM_MMR6<"seh", 0b0011101100>;
 class SELEQZ_MMR6_ENC : POOL32A_FM_MMR6<0b0101000000>;
class WRPGPR_WSBH_MMR6_DESC_BASE<string instr_asm, RegisterOperand RO>
   list<dag> Pattern = [];
   Format f = FrmR;
   string BaseOpcode = instr_asm;
   bit hasSideEffects = 0;
 }
 class WRPGPR_MMR6_DESC : WRPGPR_WSBH_MMR6_DESC_BASE<"wrpgpr", GPR32Opnd>;
 class WSBH_MMR6_DESC : WRPGPR_WSBH_MMR6_DESC_BASE<"wsbh", GPR32Opnd>;
 
+class MTC0_MMR6_DESC_BASE<string instr_asm, RegisterOperand DstRC,
+                         RegisterOperand SrcRC> {
+  dag InOperandList = (ins SrcRC:$rt, uimm3:$sel);
+  dag OutOperandList = (outs DstRC:$rs);
+  string AsmString = !strconcat(instr_asm, "\t$rt, $rs, $sel");
+  list<dag> Pattern = [];
+  Format f = FrmFR;
+  string BaseOpcode = instr_asm;
+}
+class MTC1_MMR6_DESC_BASE<
+      string instr_asm, RegisterOperand DstRC, RegisterOperand SrcRC,
+      InstrItinClass Itin = NoItinerary,SDPatternOperator OpNode = null_frag> {
+  dag InOperandList = (ins SrcRC:$rt);
+  dag OutOperandList = (outs DstRC:$fs);
+  string AsmString = !strconcat(instr_asm, "\t$rt, $fs");
+  list<dag> Pattern = [(set DstRC:$fs, (OpNode SrcRC:$rt))];
+  Format f = FrmFR;
+  InstrItinClass Itinerary = Itin;
+  string BaseOpcode = instr_asm;
+}
+class MTC2_MMR6_DESC_BASE<string instr_asm, RegisterOperand DstRC,
+                         RegisterOperand SrcRC> {
+  dag InOperandList = (ins SrcRC:$rt);
+  dag OutOperandList = (outs DstRC:$impl);
+  string AsmString = !strconcat(instr_asm, "\t$rt, $impl");
+  list<dag> Pattern = [];
+  Format f = FrmFR;
+  string BaseOpcode = instr_asm;
+}
+
+class MTC0_MMR6_DESC : MTC0_MMR6_DESC_BASE<"mtc0", COP0Opnd, GPR32Opnd>;
+class MTC1_MMR6_DESC : MTC1_MMR6_DESC_BASE<"mtc1", FGR32Opnd, GPR32Opnd,
+                                           II_MTC1, bitconvert>, HARDFLOAT;
+class MTC2_MMR6_DESC : MTC2_MMR6_DESC_BASE<"mtc2", COP2Opnd, GPR32Opnd>;
+class MTHC0_MMR6_DESC : MTC0_MMR6_DESC_BASE<"mthc0", COP0Opnd, GPR32Opnd>;
+class MTHC1_MMR6_DESC : MTC1_MMR6_DESC_BASE<"mthc1", AFGR64Opnd, GPR32Opnd>,
+                        HARDFLOAT;
+class MTHC2_MMR6_DESC : MTC2_MMR6_DESC_BASE<"mthc2", COP2Opnd, GPR32Opnd>;
+
 /// Floating Point Instructions
 class FARITH_MMR6_DESC_BASE<string instr_asm, RegisterOperand RC,
                             InstrItinClass Itin, bit isComm,
                             SDPatternOperator OpNode = null_frag> : HARDFLOAT {
   dag OutOperandList = (outs RC:$fd);
   dag InOperandList = (ins RC:$ft, RC:$fs);
   string AsmString = !strconcat(instr_asm, "\t$fd, $fs, $ft");
   list<dag> Pattern = [(set RC:$fd, (OpNode RC:$fs, RC:$ft))];

 def JIALC_MMR6 : R6MMR6Rel, JIALC_MMR6_ENC, JIALC_MMR6_DESC, ISA_MICROMIPS32R6;
 def JIC_MMR6 : R6MMR6Rel, JIC_MMR6_ENC, JIC_MMR6_DESC, ISA_MICROMIPS32R6;
 def JRC16_MMR6 : R6MMR6Rel, JRC16_MMR6_DESC, JRC16_MMR6_ENC, ISA_MICROMIPS32R6;
 def JRCADDIUSP_MMR6 : R6MMR6Rel, JRCADDIUSP_MMR6_DESC, JRCADDIUSP_MMR6_ENC,
                       ISA_MICROMIPS32R6;
 def LSA_MMR6 : R6MMR6Rel, LSA_MMR6_ENC, LSA_MMR6_DESC, ISA_MICROMIPS32R6;
 def LWPC_MMR6 : R6MMR6Rel, LWPC_MMR6_ENC, LWPC_MMR6_DESC, ISA_MICROMIPS32R6;
 def LWM16_MMR6 : StdMMR6Rel, LWM16_MMR6_DESC, LWM16_MMR6_ENC, ISA_MICROMIPS32R6;
+def MTC0_MMR6 : StdMMR6Rel, MTC0_MMR6_ENC, MTC0_MMR6_DESC, ISA_MICROMIPS32R6;
+def MTC1_MMR6 : StdMMR6Rel, MTC1_MMR6_ENC, MTC1_MMR6_DESC, ISA_MICROMIPS32R6;
+def MTC2_MMR6 : StdMMR6Rel, MTC2_MMR6_ENC, MTC2_MMR6_DESC, ISA_MICROMIPS32R6;
+def MTHC0_MMR6 : R6MMR6Rel, MTHC0_MMR6_ENC, MTHC0_MMR6_DESC, ISA_MICROMIPS32R6;
+def MTHC1_MMR6 : StdMMR6Rel, MTHC1_MMR6_ENC, MTHC1_MMR6_DESC, ISA_MICROMIPS32R6;
+def MTHC2_MMR6 : StdMMR6Rel, MTHC2_MMR6_ENC, MTHC2_MMR6_DESC, ISA_MICROMIPS32R6;
 def MOD_MMR6 : R6MMR6Rel, MOD_MMR6_DESC, MOD_MMR6_ENC, ISA_MICROMIPS32R6;
 def MODU_MMR6 : R6MMR6Rel, MODU_MMR6_DESC, MODU_MMR6_ENC, ISA_MICROMIPS32R6;
 def MUL_MMR6 : R6MMR6Rel, MUL_MMR6_DESC, MUL_MMR6_ENC, ISA_MICROMIPS32R6;
 def MUH_MMR6 : R6MMR6Rel, MUH_MMR6_DESC, MUH_MMR6_ENC, ISA_MICROMIPS32R6;
 def MULU_MMR6 : R6MMR6Rel, MULU_MMR6_DESC, MULU_MMR6_ENC, ISA_MICROMIPS32R6;
 def MUHU_MMR6 : R6MMR6Rel, MUHU_MMR6_DESC, MUHU_MMR6_ENC, ISA_MICROMIPS32R6;
 def NOR_MMR6 : StdMMR6Rel, NOR_MMR6_DESC, NOR_MMR6_ENC, ISA_MICROMIPS32R6;
 def OR_MMR6 : StdMMR6Rel, OR_MMR6_DESC, OR_MMR6_ENC, ISA_MICROMIPS32R6;
def B_MMR6_Pseudo : MipsAsmPseudoInst<(outs), (ins brtarget_mm:$offset),
                                       !strconcat("b", "\t$offset")> {
   string DecoderNamespace = "MicroMipsR6";
 }
 def : MipsInstAlias<"sync", (SYNC_MMR6 0), 1>, ISA_MICROMIPS32R6;
 def : MipsInstAlias<"sdbbp", (SDBBP_MMR6 0), 1>, ISA_MICROMIPS32R6;
 def : MipsInstAlias<"rdhwr $rt, $rs",
                     (RDHWR_MMR6 GPR32Opnd:$rt, HWRegsOpnd:$rs, 0), 1>,
                     ISA_MICROMIPS32R6;
+def : MipsInstAlias<"mtc0 $rt, $rs",
+                    (MTC0_MMR6 COP0Opnd:$rs, GPR32Opnd:$rt, 0), 0>,
+                    ISA_MICROMIPS32R6;
+def : MipsInstAlias<"mthc0 $rt, $rs",
+                    (MTHC0_MMR6 COP0Opnd:$rs, GPR32Opnd:$rt, 0), 0>,
+                    ISA_MICROMIPS32R6;
 
 //===----------------------------------------------------------------------===//
 //
 // MicroMips arbitrary patterns that map to one or more instructions
 //
 //===----------------------------------------------------------------------===//
 
 def : MipsPat<(store GPRMM16:$src, addrimm4lsl2:$addr),
               (SW16_MMR6 GPRMM16:$src, addrimm4lsl2:$addr)>, ISA_MICROMIPS32R6;

lib/Target/Mips/MicroMips64r6InstrFormats.td

class POOL32A_DIVMOD_FM_MMR6<string instr_asm, bits<9> funct>
 
   let Inst{31-26} = 0b010110;
   let Inst{25-21} = rd;
   let Inst{20-16} = rs;
   let Inst{15-11} = rt;
   let Inst{10-9}  = 0b00;
   let Inst{8-0}  = funct;
 }
+
+class POOL32S_DMFTC0_FM_MMR6<string instr_asm, bits<5> funct>
+    : MMR6Arch<instr_asm>, MipsR6Inst {
+  bits<5> rt;
+  bits<5> rs;
+  bits<3> sel;
+
+  bits<32> Inst;
+
+  let Inst{31-26} = 0b010110;
+  let Inst{25-21} = rt;
+  let Inst{20-16} = rs;
+  let Inst{15-14} = 0;
+  let Inst{13-11} = sel;
+  let Inst{10-6}  = funct;
+  let Inst{5-0}   = 0b111100;
+}

lib/Target/Mips/MicroMips64r6InstrInfo.td

 class DEXT_MMR6_ENC : POOL32S_EXTBITS_FM_MMR6<0b101100>;
 class DEXTM_MMR6_ENC : POOL32S_EXTBITS_FM_MMR6<0b100100>;
 class DEXTU_MMR6_ENC : POOL32S_EXTBITS_FM_MMR6<0b010100>;
 class DALIGN_MMR6_ENC : POOL32S_DALIGN_FM_MMR6;
 class DDIV_MM64R6_ENC : POOL32A_DIVMOD_FM_MMR6<"ddiv", 0b100011000>;
 class DMOD_MM64R6_ENC : POOL32A_DIVMOD_FM_MMR6<"dmod", 0b101011000>;
 class DDIVU_MM64R6_ENC : POOL32A_DIVMOD_FM_MMR6<"ddivu", 0b110011000>;
 class DMODU_MM64R6_ENC : POOL32A_DIVMOD_FM_MMR6<"dmodu", 0b111011000>;
+class DMTC0_MM64R6_ENC : POOL32S_DMFTC0_FM_MMR6<"dmtc0", 0b01011>;
+class DMTC1_MM64R6_ENC : POOL32F_MFTC1_FM_MMR6<"dmtc1", 0b10110000>;
+class DMTC2_MM64R6_ENC : POOL32A_MFTC2_FM_MMR6<"dmtc2", 0b0111110100>;
 
 //===----------------------------------------------------------------------===//
 //
 // Instruction Descriptions
 //
 //===----------------------------------------------------------------------===//
 
 class DAUI_MMR6_DESC_BASE<string instr_asm, RegisterOperand GPROpnd>

 
 class DALIGN_MMR6_DESC : DALIGN_DESC_BASE<"dalign", GPR64Opnd, uimm3>;
 
 class DDIV_MM64R6_DESC : ArithLogicR<"ddiv", GPR32Opnd>;
 class DMOD_MM64R6_DESC : ArithLogicR<"dmod", GPR32Opnd>;
 class DDIVU_MM64R6_DESC : ArithLogicR<"ddivu", GPR32Opnd>;
 class DMODU_MM64R6_DESC : ArithLogicR<"dmodu", GPR32Opnd>;
 
+class DMTC0_MM64R6_DESC : MTC0_MMR6_DESC_BASE<"dmtc0", COP0Opnd, GPR64Opnd>;
+class DMTC1_MM64R6_DESC : MTC1_MMR6_DESC_BASE<"dmtc1", FGR64Opnd, GPR64Opnd,
+                                              II_DMTC1, bitconvert>;
+class DMTC2_MM64R6_DESC : MTC2_MMR6_DESC_BASE<"dmtc2", COP2Opnd, GPR64Opnd>;
+
 //===----------------------------------------------------------------------===//
 //
 // Instruction Definitions
 //
 //===----------------------------------------------------------------------===//
 
 let DecoderNamespace = "MicroMipsR6" in {
   def DAUI_MM64R6 : StdMMR6Rel, DAUI_MMR6_DESC, DAUI_MMR6_ENC, ISA_MICROMIPS64R6;
let DecoderNamespace = "MicroMipsR6" in {
   def DDIV_MM64R6 : R6MMR6Rel, DDIV_MM64R6_DESC, DDIV_MM64R6_ENC,
                     ISA_MICROMIPS64R6;
   def DMOD_MM64R6 : R6MMR6Rel, DMOD_MM64R6_DESC, DMOD_MM64R6_ENC,
                     ISA_MICROMIPS64R6;
   def DDIVU_MM64R6 : R6MMR6Rel, DDIVU_MM64R6_DESC, DDIVU_MM64R6_ENC,
                      ISA_MICROMIPS64R6;
   def DMODU_MM64R6 : R6MMR6Rel, DMODU_MM64R6_DESC, DMODU_MM64R6_ENC,
                      ISA_MICROMIPS64R6;
+  def DMTC0_MM64R6 : StdMMR6Rel, DMTC0_MM64R6_ENC, DMTC0_MM64R6_DESC,
+                     ISA_MICROMIPS64R6;
+  def DMTC1_MM64R6 : StdMMR6Rel, DMTC1_MM64R6_ENC, DMTC1_MM64R6_DESC,
+                     ISA_MICROMIPS64R6;
+  def DMTC2_MM64R6 : StdMMR6Rel, DMTC2_MM64R6_ENC, DMTC2_MM64R6_DESC,
+                     ISA_MICROMIPS64R6;
 }
+
+//===----------------------------------------------------------------------===//
+// Instruction aliases
+//===----------------------------------------------------------------------===//
+def : MipsInstAlias<"dmtc0 $rt, $rd",
+                    (DMTC0_MM64R6 COP0Opnd:$rd, GPR64Opnd:$rt, 0), 0>;

lib/Target/Mips/Mips64InstrInfo.td

def : MipsInstAlias<"dsra $rd, $rt, $rs",
                     (DSRAV GPR64Opnd:$rd, GPR64Opnd:$rt, GPR32Opnd:$rs), 0>,
                     ISA_MIPS3;
 def : MipsInstAlias<"dsrl $rd, $rt, $rs",
                     (DSRLV GPR64Opnd:$rd, GPR64Opnd:$rt, GPR32Opnd:$rs), 0>,
                     ISA_MIPS3;
 
 // Two operand (implicit 0 selector) versions:
 def : MipsInstAlias<"dmfc0 $rt, $rd", (DMFC0 GPR64Opnd:$rt, COP0Opnd:$rd, 0), 0>;
-def : MipsInstAlias<"dmtc0 $rt, $rd", (DMTC0 COP0Opnd:$rd, GPR64Opnd:$rt, 0), 0>;
+let AdditionalPredicates = [NotInMicroMips] in {
+  def : MipsInstAlias<"dmtc0 $rt, $rd",
+                      (DMTC0 COP0Opnd:$rd, GPR64Opnd:$rt, 0), 0>;
+}
 def : MipsInstAlias<"dmfc2 $rt, $rd", (DMFC2 GPR64Opnd:$rt, COP2Opnd:$rd, 0), 0>;
 def : MipsInstAlias<"dmtc2 $rt, $rd", (DMTC2 COP2Opnd:$rd, GPR64Opnd:$rt, 0), 0>;
 
 let Predicates = [HasMips64, HasCnMips] in {
 def : MipsInstAlias<"synciobdma", (SYNC 0x2), 0>;
 def : MipsInstAlias<"syncs",      (SYNC 0x6), 0>;
 def : MipsInstAlias<"syncw",      (SYNC 0x4), 0>;
 def : MipsInstAlias<"syncws",     (SYNC 0x5), 0>;

lib/Target/Mips/MipsInstrFPU.td

 def MTHC1_D32 : MMRel, MTC1_64_FT<"mthc1", AFGR64Opnd, GPR32Opnd, II_MTHC1>,
                 MFC1_FM<7>, ISA_MIPS32R2, FGR_32;
 def MTHC1_D64 : MTC1_64_FT<"mthc1", FGR64Opnd, GPR32Opnd, II_MTHC1>,
                 MFC1_FM<7>, ISA_MIPS32R2, FGR_64 {
   let DecoderNamespace = "Mips64";
 }
 def DMFC1 : MFC1_FT<"dmfc1", GPR64Opnd, FGR64Opnd, II_DMFC1,
             bitconvert>, MFC1_FM<1>, ISA_MIPS3;
+let AdditionalPredicates = [NotInMicroMips] in {
   def DMTC1 : MTC1_FT<"dmtc1", FGR64Opnd, GPR64Opnd, II_DMTC1,
               bitconvert>, MFC1_FM<5>, ISA_MIPS3;
+}
 
 def FMOV_S   : MMRel, ABSS_FT<"mov.s", FGR32Opnd, FGR32Opnd, II_MOV_S>,
                ABSS_FM<0x6, 16>;
 def FMOV_D32 : MMRel, ABSS_FT<"mov.d", AFGR64Opnd, AFGR64Opnd, II_MOV_D>,
                ABSS_FM<0x6, 17>, FGR_32;
 def FMOV_D64 : ABSS_FT<"mov.d", FGR64Opnd, FGR64Opnd, II_MOV_D>,
                ABSS_FM<0x6, 17>, FGR_64 {
                  let DecoderNamespace = "Mips64";

lib/Target/Mips/MipsInstrInfo.td

class SCBase<string opstr, RegisterOperand RO> :
   let Constraints = "$rt = $dst";
 }
 
 class MFC3OP<string asmstr, RegisterOperand RO, RegisterOperand RD> :
   InstSE<(outs RO:$rt), (ins RD:$rd, uimm16:$sel),
          !strconcat(asmstr, "\t$rt, $rd, $sel"), [], NoItinerary, FrmFR>;
 
 class MTC3OP<string asmstr, RegisterOperand RO, RegisterOperand RD> :
-  InstSE<(outs RO:$rd), (ins RD:$rt, uimm16:$sel),
+  InstSE<(outs RO:$rd), (ins RD:$rt, uimm3:$sel),
          !strconcat(asmstr, "\t$rt, $rd, $sel"), [], NoItinerary, FrmFR>;
 
 class TrapBase<Instruction RealInst>
   : PseudoSE<(outs), (ins), [(trap)], NoItinerary>,
     PseudoInstExpansion<(RealInst 0, 0)> {
   let isBarrier = 1;
   let isTerminator = 1;
   let isCodeGenOnly = 1;

 }
 // TODO: Add '0 < pos+size <= 32' constraint check to ext instruction
 def EXT : MMRel, ExtBase<"ext", GPR32Opnd, uimm5, uimm5_plus1, MipsExt>,
           EXT_FM<0>;
 def INS : MMRel, InsBase<"ins", GPR32Opnd, uimm5, MipsIns>, EXT_FM<4>;
 
 /// Move Control Registers From/To CPU Registers
 def MFC0 : MFC3OP<"mfc0", GPR32Opnd, COP0Opnd>, MFC3OP_FM<0x10, 0>, ISA_MIPS32;
-def MTC0 : MTC3OP<"mtc0", COP0Opnd, GPR32Opnd>, MFC3OP_FM<0x10, 4>, ISA_MIPS32;
+let AdditionalPredicates = [NotInMicroMips] in {
+  def MTC0 : MTC3OP<"mtc0", COP0Opnd, GPR32Opnd>, MFC3OP_FM<0x10, 4>,
+             ISA_MIPS32;
+}
 def MFC2 : MFC3OP<"mfc2", GPR32Opnd, COP2Opnd>, MFC3OP_FM<0x12, 0>;
 def MTC2 : MTC3OP<"mtc2", COP2Opnd, GPR32Opnd>, MFC3OP_FM<0x12, 4>;
 
 class Barrier<string asmstr> : InstSE<(outs), (ins), asmstr, [], NoItinerary,
                                       FrmOther, asmstr>;
 def SSNOP : MMRel, StdMMR6Rel, Barrier<"ssnop">, BARRIER_FM<1>;
 def EHB : MMRel, Barrier<"ehb">, BARRIER_FM<3>;
 def PAUSE : MMRel, StdMMR6Rel, Barrier<"pause">, BARRIER_FM<5>, ISA_MIPS32R2;

test/MC/Disassembler/Mips/micromips32r6/valid.txt

 0x54 0x62 0x08 0x38 # CHECK: seleqz.s $f1, $f2, $f3
 0x55 0x04 0x12 0x38 # CHECK: seleqz.d $f2, $f4, $f8
 0x54 0x62 0x08 0x78 # CHECK: selnez.s $f1, $f2, $f3
 0x55 0x04 0x12 0x78 # CHECK: selnez.d $f2, $f4, $f8
 0x54 0x62 0x00 0x60 # CHECK: class.s $f2, $f3
 0x54 0x82 0x02 0x60 # CHECK: class.d $f2, $f4
 0x00 0x00 0x47 0x7c # CHECK: di
 0x00 0x0f 0x47 0x7c # CHECK: di $15
+0x00 0xa9 0x02 0xfc # CHECK: mtc0 $5, $9, 0
+0x00 0x22 0x3a 0xfc # CHECK: mtc0 $1, $2, 7
+0x54 0x64 0x28 0x3b # CHECK: mtc1 $3, $f4
+0x00 0xa6 0x5d 0x3c # CHECK: mtc2 $5, $6
+0x00 0xe8 0x02 0xf4 # CHECK: mthc0 $7, $8, 0
+0x01 0x2a 0x0a 0xf4 # CHECK: mthc0 $9, $10, 1
+0x55 0x6c 0x38 0x3b # CHECK: mthc1 $11, $f12
+0x01 0xae 0x9d 0x3c # CHECK: $13, $14

test/MC/Disassembler/Mips/micromips64r6/valid.txt

 0x55 0x04 0x12 0x38 # CHECK: seleqz.d $f2, $f4, $f8
 0x54 0x62 0x08 0x78 # CHECK: selnez.s $f1, $f2, $f3
 0x55 0x04 0x12 0x78 # CHECK: selnez.d $f2, $f4, $f8
 0x54 0x62 0x00 0x60 # CHECK: class.s $f2, $f3
 0x54 0x82 0x02 0x60 # CHECK: class.d $f2, $f4
 0x00 0x00 0xe3 0x7c # CHECK: deret
 0x00 0x00 0x47 0x7c # CHECK: di
 0x00 0x0f 0x47 0x7c # CHECK: di $15
+0x59 0xf0 0x02 0xfc # CHECK: dmtc0 $15, $16, 0
+0x5a 0x32 0x2a 0xfc # CHECK: dmtc0 $17, $18, 5
+0x56 0x74 0x2c 0x3b # CHECK: dmtc1 $19, $f20
+0x02 0xb6 0x7d 0x3c # CHECK: dmtc2 $21, $22

test/MC/Mips/micromips32r6/invalid.s

# RUN: FileCheck %s < %t1
   swm16 $5, $6, $ra, 8($sp)   # CHECK: :[[@LINE]]:{{[0-9]+}}: error: $16 or $31 expected
   swm16 $16, $19, $ra, 8($sp) # CHECK: :[[@LINE]]:{{[0-9]+}}: error: consecutive register numbers expected
   swm16 $16-$25, $ra, 8($sp)  # CHECK: :[[@LINE]]:{{[0-9]+}}: error: invalid register operand
   swm16 $16, 8($sp)           # CHECK: :[[@LINE]]:{{[0-9]+}}: error: invalid operand for instruction
   swm16 $16, $17, 8($sp)      # CHECK: :[[@LINE]]:{{[0-9]+}}: error: invalid operand for instruction
   swm16 $16-$20, 8($sp)       # CHECK: :[[@LINE]]:{{[0-9]+}}: error: invalid operand for instruction
   swm16 $16, $17, $ra, 8($fp)  # CHECK: :[[@LINE]]:{{[0-9]+}}: error: invalid operand for instruction
   swm16 $16, $17, $ra, 64($sp) # CHECK: :[[@LINE]]:{{[0-9]+}}: error: invalid operand for instruction
+  mtc0  $4, $3, -1         # CHECK: :[[@LINE]]:17: error: expected 3-bit unsigned immediate
+  mtc0  $4, $3, 8          # CHECK: :[[@LINE]]:17: error: expected 3-bit unsigned immediate
+  mthc0 $4, $3, -1         # CHECK: :[[@LINE]]:17: error: expected 3-bit unsigned immediate
+  mthc0 $4, $3, 8          # CHECK: :[[@LINE]]:17: error: expected 3-bit unsigned immediate

test/MC/Mips/micromips32r6/valid.s

# RUN: llvm-mc %s -triple=mips-unknown-linux -show-encoding -mcpu=mips32r6 -mattr=micromips | FileCheck %s
   sel.d $f0, $f2, $f4      # CHECK: sel.d $f0, $f2, $f4 # encoding: [0x54,0x82,0x02,0xb8]
   seleqz.s $f1, $f2, $f3   # CHECK: seleqz.s $f1, $f2, $f3 # encoding: [0x54,0x62,0x08,0x38]
   seleqz.d $f2, $f4, $f8   # CHECK: seleqz.d $f2, $f4, $f8 # encoding: [0x55,0x04,0x12,0x38]
   selnez.s $f1, $f2, $f3   # CHECK: selnez.s $f1, $f2, $f3 # encoding: [0x54,0x62,0x08,0x78]
   selnez.d $f2, $f4, $f8   # CHECK: selnez.d $f2, $f4, $f8 # encoding: [0x55,0x04,0x12,0x78]
   class.s $f2, $f3         # CHECK: class.s $f2, $f3       # encoding: [0x54,0x62,0x00,0x60]
   class.d $f2, $f4         # CHECK: class.d $f2, $f4       # encoding: [0x54,0x82,0x02,0x60]
   deret                    # CHECK: deret                  # encoding: [0x00,0x00,0xe3,0x7c]
+  mtc0 $5, $9              # CHECK: mtc0 $5, $9, 0      # encoding: [0x00,0xa9,0x02,0xfc]
+  mtc0 $1, $2, 7           # CHECK: mtc0 $1, $2, 7      # encoding: [0x00,0x22,0x3a,0xfc]
+  mtc1 $3, $f4             # CHECK: mtc1 $3, $f4        # encoding: [0x54,0x64,0x28,0x3b]
+  mtc2 $5, $6              # CHECK: mtc2 $5, $6         # encoding: [0x00,0xa6,0x5d,0x3c]
+  mthc0 $7, $8             # CHECK: mthc0 $7, $8, 0     # encoding: [0x00,0xe8,0x02,0xf4]
+  mthc0 $9, $10, 1         # CHECK: mthc0 $9, $10, 1    # encoding: [0x01,0x2a,0x0a,0xf4]
+  mthc1 $11, $f12          # CHECK: mthc1 $11, $f12     # encoding: [0x55,0x6c,0x38,0x3b]
+  mthc2 $13, $14           # CHECK: mthc2 $13, $14      # encoding: [0x01,0xae,0x9d,0x3c]

test/MC/Mips/micromips64r6/invalid.s

# RUN: FileCheck %s < %t1
   swm16 $5, $6, $ra, 8($sp)   # CHECK: :[[@LINE]]:{{[0-9]+}}: error: $16 or $31 expected
   swm16 $16, $19, $ra, 8($sp) # CHECK: :[[@LINE]]:{{[0-9]+}}: error: consecutive register numbers expected
   swm16 $16-$25, $ra, 8($sp)  # CHECK: :[[@LINE]]:{{[0-9]+}}: error: invalid register operand
   swm16 $16, 8($sp)           # CHECK: :[[@LINE]]:{{[0-9]+}}: error: invalid operand for instruction
   swm16 $16, $17, 8($sp)      # CHECK: :[[@LINE]]:{{[0-9]+}}: error: invalid operand for instruction
   swm16 $16-$20, 8($sp)       # CHECK: :[[@LINE]]:{{[0-9]+}}: error: invalid operand for instruction
   swm16 $16, $17, $ra, 8($fp)  # CHECK: :[[@LINE]]:{{[0-9]+}}: error: invalid operand for instruction
   swm16 $16, $17, $ra, 64($sp) # CHECK: :[[@LINE]]:{{[0-9]+}}: error: invalid operand for instruction
+  dmtc0  $4, $3, -1        # CHECK: :[[@LINE]]:18: error: expected 3-bit unsigned immediate
+  dmtc0  $4, $3, 8         # CHECK: :[[@LINE]]:18: error: expected 3-bit unsigned immediate

test/MC/Mips/micromips64r6/valid.s

a:
         deret                    # CHECK: deret                   # encoding: [0x00,0x00,0xe3,0x7c]
         di                       # CHECK: di                      # encoding: [0x00,0x00,0x47,0x7c]
         di $0                    # CHECK: di                      # encoding: [0x00,0x00,0x47,0x7c]
         di $15                   # CHECK: di $15                  # encoding: [0x00,0x0f,0x47,0x7c]
         ceil.l.s $f1, $f3        # CHECK: ceil.l.s $f1, $f3       # encoding: [0x54,0x23,0x13,0x3b]
         ceil.l.d $f1, $f3        # CHECK: ceil.l.d $f1, $f3       # encoding: [0x54,0x23,0x53,0x3b]
         floor.l.s $f1, $f3       # CHECK: floor.l.s $f1, $f3      # encoding: [0x54,0x23,0x03,0x3b]
         floor.l.d $f1, $f3       # CHECK: floor.l.d $f1, $f3      # encoding: [0x54,0x23,0x43,0x3b]
+        dmtc0 $15, $16           # CHECK: dmtc0 $15, $16, 0       # encoding: [0x59,0xf0,0x02,0xfc]
+        dmtc0 $17, $18, 5        # CHECK: dmtc0 $17, $18, 5       # encoding: [0x5a,0x32,0x2a,0xfc]
+        dmtc1 $19, $f20          # CHECK: dmtc1 $19, $f20         # encoding: [0x56,0x74,0x2c,0x3b]
+        dmtc2 $21, $22           # CHECK: dmtc2 $21, $22          # encoding: [0x02,0xb6,0x7d,0x3c]
 
 1:

test/MC/Mips/mips32r5/invalid.s

 # Instructions that are valid for the current ISA but should be rejected by the assembler (e.g.
 # invalid set of operands or operand's restrictions not met).
 
 # RUN: not llvm-mc %s -triple=mips-unknown-linux -mcpu=mips32r5 2>%t1
 # RUN: FileCheck %s < %t1
 
         .text
         .set noreorder
         cache -1, 255($7)    # CHECK: :[[@LINE]]:15: error: expected 5-bit unsigned immediate
         cache 32, 255($7)    # CHECK: :[[@LINE]]:15: error: expected 5-bit unsigned immediate
         jalr.hb $31          # CHECK: :[[@LINE]]:9: error: source and destination must be different
         jalr.hb $31, $31     # CHECK: :[[@LINE]]:9: error: source and destination must be different
         pref -1, 255($7)     # CHECK: :[[@LINE]]:14: error: expected 5-bit unsigned immediate
         pref 32, 255($7)     # CHECK: :[[@LINE]]:14: error: expected 5-bit unsigned immediate
+        mtc0  $4, $3, -1     # CHECK: :[[@LINE]]:23: error: expected 3-bit unsigned immediate
+        mtc0  $4, $3, 8      # CHECK: :[[@LINE]]:23: error: expected 3-bit unsigned immediate
+        mthc0 $4, $3, -1     # CHECK: :[[@LINE]]:23: error: expected 3-bit unsigned immediate
+        mthc0 $4, $3, 8      # CHECK: :[[@LINE]]:23: error: expected 3-bit unsigned immediate
+        mtc2  $4, $3, -1     # CHECK: :[[@LINE]]:23: error: expected 3-bit unsigned immediate
+        mtc2  $4, $3, 8      # CHECK: :[[@LINE]]:23: error: expected 3-bit unsigned immediate

test/MC/Mips/mips32r6/invalid.s

local_label:
         cache -1, 255($7)    # CHECK: :[[@LINE]]:15: error: expected 5-bit unsigned immediate
         cache 32, 255($7)    # CHECK: :[[@LINE]]:15: error: expected 5-bit unsigned immediate
         jalr.hb $31          # CHECK: :[[@LINE]]:9: error: source and destination must be different
         jalr.hb $31, $31     # CHECK: :[[@LINE]]:9: error: source and destination must be different
         lsa $2, $3, $4, 0    # CHECK: :[[@LINE]]:25: error: expected immediate in range 1 .. 4
         lsa $2, $3, $4, 5    # CHECK: :[[@LINE]]:25: error: expected immediate in range 1 .. 4
         pref -1, 255($7)     # CHECK: :[[@LINE]]:14: error: expected 5-bit unsigned immediate
         pref 32, 255($7)     # CHECK: :[[@LINE]]:14: error: expected 5-bit unsigned immediate
+        mtc0  $4, $3, -1     # CHECK: :[[@LINE]]:23: error: expected 3-bit unsigned immediate
+        mtc0  $4, $3, 8      # CHECK: :[[@LINE]]:23: error: expected 3-bit unsigned immediate
+        mthc0 $4, $3, -1     # CHECK: :[[@LINE]]:23: error: expected 3-bit unsigned immediate
+        mthc0 $4, $3, 8      # CHECK: :[[@LINE]]:23: error: expected 3-bit unsigned immediate
+        mtc2  $4, $3, -1     # CHECK: :[[@LINE]]:23: error: expected 3-bit unsigned immediate
+        mtc2  $4, $3, 8      # CHECK: :[[@LINE]]:23: error: expected 3-bit unsigned immediate

test/MC/Mips/mips64r5/invalid.s

 # Instructions that are valid for the current ISA but should be rejected by the assembler (e.g.
 # invalid set of operands or operand's restrictions not met).
 
 # RUN: not llvm-mc %s -triple=mips64-unknown-linux -mcpu=mips64r5 2>%t1
 # RUN: FileCheck %s < %t1
 
         .text
         .set noreorder
         cache -1, 255($7)    # CHECK: :[[@LINE]]:15: error: expected 5-bit unsigned immediate
         cache 32, 255($7)    # CHECK: :[[@LINE]]:15: error: expected 5-bit unsigned immediate
         drotr32 $2, $3, -1   # CHECK: :[[@LINE]]:25: error: expected 5-bit unsigned immediate
         drotr32 $2, $3, 32   # CHECK: :[[@LINE]]:25: error: expected 5-bit unsigned immediate
         jalr.hb $31          # CHECK: :[[@LINE]]:{{[0-9]+}}: error: source and destination must be different
         jalr.hb $31, $31     # CHECK: :[[@LINE]]:{{[0-9]+}}: error: source and destination must be different
         pref -1, 255($7)     # CHECK: :[[@LINE]]:14: error: expected 5-bit unsigned immediate
         pref 32, 255($7)     # CHECK: :[[@LINE]]:14: error: expected 5-bit unsigned immediate
+        dmtc0  $4, $3, -1    # CHECK: :[[@LINE]]:24: error: expected 3-bit unsigned immediate
+        dmtc0  $4, $3, 8     # CHECK: :[[@LINE]]:24: error: expected 3-bit unsigned immediate
+        dmtc2  $4, $3, -1    # CHECK: :[[@LINE]]:24: error: expected 3-bit unsigned immediate
+        dmtc2  $4, $3, 8     # CHECK: :[[@LINE]]:24: error: expected 3-bit unsigned immediate

test/MC/Mips/mips64r6/invalid.s

.set noat
         drotr32 $2, $3, -1   # CHECK: :[[@LINE]]:25: error: expected 5-bit unsigned immediate
         drotr32 $2, $3, 32   # CHECK: :[[@LINE]]:25: error: expected 5-bit unsigned immediate
         jalr.hb $31          # CHECK: :[[@LINE]]:{{[0-9]+}}: error: source and destination must be different
         jalr.hb $31, $31     # CHECK: :[[@LINE]]:{{[0-9]+}}: error: source and destination must be different
         lsa     $2, $3, $4, 0     # CHECK: :[[@LINE]]:29: error: expected immediate in range 1 .. 4
         lsa     $2, $3, $4, 5     # CHECK: :[[@LINE]]:29: error: expected immediate in range 1 .. 4
         pref -1, 255($7)     # CHECK: :[[@LINE]]:14: error: expected 5-bit unsigned immediate
         pref 32, 255($7)     # CHECK: :[[@LINE]]:14: error: expected 5-bit unsigned immediate
+        dmtc0  $4, $3, -1    # CHECK: :[[@LINE]]:24: error: expected 3-bit unsigned immediate
+        dmtc0  $4, $3, 8     # CHECK: :[[@LINE]]:24: error: expected 3-bit unsigned immediate
+        dmtc2  $4, $3, -1    # CHECK: :[[@LINE]]:24: error: expected 3-bit unsigned immediate
+        dmtc2  $4, $3, 8     # CHECK: :[[@LINE]]:24: error: expected 3-bit unsigned immediate