[mips][microMIPS] Implement ADDU16 and SUBU16 instructions

[jkolek]

Summary

Implement microMIPS 16-bit ADDU16 and SUBU16 instructions.

[sstankovic]

LGTM

Closed by commit rL220276 (authored by zjovanovic).

lib/Target/Mips/MicroMipsInstrFormats.td

class MicroMipsInst16<dag outs, dag ins, string asmstr, list<dag> pattern,
   field bits<16> SoftFail = 0;
   bits<6> Opcode = 0x0;
 }
 
 //===----------------------------------------------------------------------===//
 // MicroMIPS 16-bit Instruction Formats
 //===----------------------------------------------------------------------===//
 
+class ARITH_FM_MM16<bit funct> {
+  bits<3> rd;
+  bits<3> rt;
+  bits<3> rs;
+
+  bits<16> Inst;
+
+  let Inst{15-10} = 0x01;
+  let Inst{9-7}   = rd;
+  let Inst{6-4}   = rt;
+  let Inst{3-1}   = rs;
+  let Inst{0}     = funct;
+}
+
 class LOGIC_FM_MM16<bits<4> funct> {
   bits<3> rt;
   bits<3> rs;
 
   bits<16> Inst;
 
   let Inst{15-10} = 0x11;
   let Inst{9-6}   = funct;

lib/Target/Mips/MicroMipsInstrInfo.td

class LoadMM<string opstr, DAGOperand RO, SDPatternOperator OpNode = null_frag,
   InstSE<(outs RO:$rt), (ins mem_mm_12:$addr),
          !strconcat(opstr, "\t$rt, $addr"),
          [(set RO:$rt, (OpNode addrimm12:$addr))], Itin, FrmI> {
   let DecoderMethod = "DecodeMemMMImm12";
   let canFoldAsLoad = 1;
   let mayLoad = 1;
 }
 
+class ArithRMM16<string opstr, RegisterOperand RO, bit isComm = 0,
+                 InstrItinClass Itin = NoItinerary,
+                 SDPatternOperator OpNode = null_frag> :
+  MicroMipsInst16<(outs RO:$rd), (ins RO:$rs, RO:$rt),
+                  !strconcat(opstr, "\t$rd, $rs, $rt"),
+                  [(set RO:$rd, (OpNode RO:$rs, RO:$rt))], Itin, FrmR> {
+  let isCommutable = isComm;
+}
+
 class LogicRMM16<string opstr, RegisterOperand RO,
                  InstrItinClass Itin = NoItinerary,
                  SDPatternOperator OpNode = null_frag> :
   MicroMipsInst16<(outs RO:$dst), (ins RO:$rs, RO:$rt),
          !strconcat(opstr, "\t$rt, $rs"),
          [(set RO:$dst, (OpNode RO:$rs, RO:$rt))], Itin, FrmR> {
   let isCommutable = 1;
   let Constraints = "$rt = $dst";
InstSE<(outs RO:$rd), (ins RO:$rs), !strconcat(opstr, "\t$rd, $rs"),
             [], IIBranch, FrmR>;
 
   class BranchCompareToZeroLinkMM<string opstr, DAGOperand opnd,
                                   RegisterOperand RO> :
     InstSE<(outs), (ins RO:$rs, opnd:$offset),
            !strconcat(opstr, "\t$rs, $offset"), [], IIBranch, FrmI, opstr>;
 }
 
+def ADDU16_MM : ArithRMM16<"addu16", GPRMM16Opnd, 1, II_ADDU, add>,
+                ARITH_FM_MM16<0>;
+def SUBU16_MM : ArithRMM16<"subu16", GPRMM16Opnd, 0, II_SUBU, sub>,
+                ARITH_FM_MM16<1>;
 def AND16_MM : LogicRMM16<"and16", GPRMM16Opnd, II_AND, and>,
                LOGIC_FM_MM16<0x2>;
 def OR16_MM  : LogicRMM16<"or16", GPRMM16Opnd, II_OR, or>,
                LOGIC_FM_MM16<0x3>;
 def XOR16_MM : LogicRMM16<"xor16", GPRMM16Opnd, II_XOR, xor>,
                LOGIC_FM_MM16<0x1>;
 def NOT16_MM : NotMM16<"not16", GPRMM16Opnd>, LOGIC_FM_MM16<0x0>;
 def ADDIUS5_MM : AddImmUS5<"addius5", GPR32Opnd>, ADDIUS5_FM_MM16;

test/MC/Mips/micromips-16-bit-instructions.s

 # RUN: llvm-mc %s -triple=mipsel -show-encoding -mattr=micromips | \
 # RUN: FileCheck -check-prefix=CHECK-EL %s
 # RUN: llvm-mc %s -triple=mips -show-encoding -mattr=micromips | \
 # RUN: FileCheck -check-prefix=CHECK-EB %s
 # Check that the assembler can handle the documented syntax
 # for arithmetic and logical instructions.
 #------------------------------------------------------------------------------
 # MicroMIPS 16-bit Instructions
 #------------------------------------------------------------------------------
 # Little endian
 #------------------------------------------------------------------------------
+# CHECK-EL: addu16  $6, $17, $4     # encoding: [0x42,0x07]
+# CHECK-EL: subu16  $5, $16, $3     # encoding: [0xb1,0x06]
 # CHECK-EL: and16   $16, $2         # encoding: [0x82,0x44]
 # CHECK-EL: not16   $17, $3         # encoding: [0x0b,0x44]
 # CHECK-EL: or16    $16, $4         # encoding: [0xc4,0x44]
 # CHECK-EL: xor16   $17, $5         # encoding: [0x4d,0x44]
 # CHECK-EL: addius5 $7, -2          # encoding: [0xfc,0x4c]
 # CHECK-EL: addiusp -16             # encoding: [0xf9,0x4f]
 # CHECK-EL: mfhi    $9              # encoding: [0x09,0x46]
 # CHECK-EL: mflo    $9              # encoding: [0x49,0x46]
 # CHECK-EL: move    $25, $1         # encoding: [0x21,0x0f]
 # CHECK-EL: jrc     $9              # encoding: [0xa9,0x45]
 # CHECK-EL: jr16    $9              # encoding: [0x89,0x45]
 # CHECK-EL: nop                     # encoding: [0x00,0x00,0x00,0x00]
 # CHECK-NEXT: jalr    $9            # encoding: [0xc9,0x45]
 # CHECK-EL: jraddiusp 20            # encoding: [0x05,0x47]
 # CHECK-EL: nop                     # encoding: [0x00,0x00,0x00,0x00]
 # CHECK-EL: jalrs16 $9              # encoding: [0xe9,0x45]
 # CHECK-EL: move    $zero, $zero    # encoding: [0x00,0x0c]
 #------------------------------------------------------------------------------
 # Big endian
 #------------------------------------------------------------------------------
+# CHECK-EB: addu16  $6, $17, $4     # encoding: [0x07,0x42]
+# CHECK-EB: subu16  $5, $16, $3     # encoding: [0x06,0xb1]
 # CHECK-EB: and16   $16, $2         # encoding: [0x44,0x82]
 # CHECK-EB: not16   $17, $3         # encoding: [0x44,0x0b]
 # CHECK-EB: or16    $16, $4         # encoding: [0x44,0xc4]
 # CHECK-EB: xor16   $17, $5         # encoding: [0x44,0x4d]
 # CHECK-EB: addius5 $7, -2          # encoding: [0x4c,0xfc]
 # CHECK-EB: addiusp -16             # encoding: [0x4f,0xf9]
 # CHECK-EB: mfhi    $9              # encoding: [0x46,0x09]
 # CHECK-EB: mflo    $9              # encoding: [0x46,0x49]
 # CHECK-EB: move    $25, $1         # encoding: [0x0f,0x21]
 # CHECK-EB: jrc     $9              # encoding: [0x45,0xa9]
 # CHECK-EB: jr16    $9              # encoding: [0x45,0x89]
 # CHECK-EB: nop                     # encoding: [0x00,0x00,0x00,0x00]
 # CHECK-NEXT: jalr    $9            # encoding: [0x45,0xc9]
 # CHECK-EB: jraddiusp 20            # encoding: [0x47,0x05]
 # CHECK-EB: nop                     # encoding: [0x00,0x00,0x00,0x00]
 # CHECK-EB: jalrs16 $9              # encoding: [0x45,0xe9]
 # CHECK-EB: move    $zero, $zero    # encoding: [0x0c,0x00]
 
+    addu16  $6, $17, $4
+    subu16  $5, $16, $3
     and16   $16, $2
     not16   $17, $3
     or16    $16, $4
     xor16   $17, $5
     addius5 $7, -2
     addiusp -16
     mfhi    $9
     mflo    $9
     move    $25, $1
     jrc     $9
     jr16    $9
     jalr    $9
     jraddiusp 20
     jalrs16 $9

test/MC/Mips/micromips-invalid.s

 # RUN: not llvm-mc %s -triple=mipsel -show-encoding -mattr=micromips 2>%t1
 # RUN: FileCheck %s < %t1
 
   addius5 $7, 9 # CHECK: :[[@LINE]]:{{[0-9]+}}: error: immediate operand value out of range
   addiusp 1032   # CHECK: :[[@LINE]]:{{[0-9]+}}: error: immediate operand value out of range
+  addu16  $6, $14, $4 # CHECK: :[[@LINE]]:{{[0-9]+}}: error: invalid operand for instruction
+  subu16  $5, $16, $9 # CHECK: :[[@LINE]]:{{[0-9]+}}: error: invalid operand for instruction
   and16   $16, $8   # CHECK: :[[@LINE]]:{{[0-9]+}}: error: invalid operand for instruction
   not16   $18, $9   # CHECK: :[[@LINE]]:{{[0-9]+}}: error: invalid operand for instruction
   or16    $16, $10  # CHECK: :[[@LINE]]:{{[0-9]+}}: error: invalid operand for instruction
   xor16   $15, $5   # CHECK: :[[@LINE]]:{{[0-9]+}}: error: invalid operand for instruction