[mips][microMIPS] Implement LLE and SCE instructions

[jkolek]

Summary

This patch implements microMIPS LLE and SCE instructions.

lib/Target/Mips/Disassembler/MipsDisassembler.cpp

                                      uint64_t Address,
                                      const void *Decoder);
 
+static DecodeStatus DecodeMemMMImm9(MCInst &Inst,
+                                     unsigned Insn,
+                                     uint64_t Address,
+                                     const void *Decoder);
+
 static DecodeStatus DecodeMemMMImm16(MCInst &Inst,
                                      unsigned Insn,
                                      uint64_t Address,

   return MCDisassembler::Success;
 }
 
+static DecodeStatus DecodeMemMMImm9(MCInst &Inst,
+                                     unsigned Insn,
+                                     uint64_t Address,
+                                     const void *Decoder) {
+  int Offset = SignExtend32<9>(Insn & 0x1ff);
+  unsigned Reg = fieldFromInstruction(Insn, 21, 5);
+  unsigned Base = fieldFromInstruction(Insn, 16, 5);
+
+  Reg = getReg(Decoder, Mips::GPR32RegClassID, Reg);
+  Base = getReg(Decoder, Mips::GPR32RegClassID, Base);
+
+  if (Inst.getOpcode() == Mips::SCE_MM)
+    Inst.addOperand(MCOperand::CreateReg(Reg));
+
+  Inst.addOperand(MCOperand::CreateReg(Reg));
+  Inst.addOperand(MCOperand::CreateReg(Base));
+  Inst.addOperand(MCOperand::CreateImm(Offset));
+
+  return MCDisassembler::Success;
+}
+
 static DecodeStatus DecodeMemMMImm16(MCInst &Inst,
                                      unsigned Insn,
                                      uint64_t Address,

lib/Target/Mips/MicroMipsInstrFormats.td

   let Inst{11-0}  = addr{11-0};
 }
 
+class LLE_FM_MM<bits<4> funct> {
+  bits<5> rt;
+  bits<21> addr;
+
+  bits<32> Inst;
+
+  let Inst{31-26} = 0x18;
+  let Inst{25-21} = rt;
+  let Inst{20-16} = addr{20-16};
+  let Inst{15-12} = funct;
+  let Inst{11-9} = 0x6;
+  let Inst{8-0}  = addr{8-0};
+}
+
 class ADDS_FM_MM<bits<2> fmt, bits<8> funct> : MMArch {
   bits<5> ft;
   bits<5> fs;

lib/Target/Mips/MicroMipsInstrInfo.td

   let mayLoad = 1;
 }
 
+class LLEBaseMM<string opstr, RegisterOperand RO> :
+  InstSE<(outs RO:$rt), (ins mem_mm_12:$addr),
+         !strconcat(opstr, "\t$rt, $addr"), [], NoItinerary, FrmI> {
+  let DecoderMethod = "DecodeMemMMImm9";
+  let mayLoad = 1;
+}
+
 class SCBaseMM<string opstr, RegisterOperand RO> :
   InstSE<(outs RO:$dst), (ins RO:$rt, mem_mm_12:$addr),
          !strconcat(opstr, "\t$rt, $addr"), [], NoItinerary, FrmI> {

   let Constraints = "$rt = $dst";
 }
 
+class SCEBaseMM<string opstr, RegisterOperand RO> :
+  InstSE<(outs RO:$dst), (ins RO:$rt, mem_mm_12:$addr),
+         !strconcat(opstr, "\t$rt, $addr"), [], NoItinerary, FrmI> {
+  let DecoderMethod = "DecodeMemMMImm9";
+  let mayStore = 1;
+  let Constraints = "$rt = $dst";
+}
+
 class LoadMM<string opstr, DAGOperand RO, SDPatternOperator OpNode = null_frag,
              InstrItinClass Itin = NoItinerary> :
   InstSE<(outs RO:$rt), (ins mem_mm_12:$addr),

   def LL_MM : LLBaseMM<"ll", GPR32Opnd>, LL_FM_MM<0x3>;
   def SC_MM : SCBaseMM<"sc", GPR32Opnd>, LL_FM_MM<0xb>;
 
+  def LLE_MM : LLEBaseMM<"lle", GPR32Opnd>, LLE_FM_MM<0x6>;
+  def SCE_MM : SCEBaseMM<"sce", GPR32Opnd>, LLE_FM_MM<0xA>;
+
   let DecoderMethod = "DecodeCacheOpMM" in {
   def CACHE_MM : MMRel, CacheOp<"cache", mem_mm_12>,
                  CACHE_PREF_FM_MM<0x08, 0x6>;

test/MC/Disassembler/Mips/micromips.txt

 
 # CHECK: movep $5, $6, $2, $3
 0x84 0x34
+
+# CHECK: lle $2, 8($4)
+0x60 0x44 0x6c 0x08
+
+# CHECK: sce $2, 8($4)
+0x60 0x44 0xac 0x08

test/MC/Disassembler/Mips/micromips_le.txt

 
 # CHECK: movep $5, $6, $2, $3
 0x34 0x84
+
+# CHECK: lle $2, 8($4)
+0x44 0x60 0x08 0x6c
+
+# CHECK: sce $2, 8($4)
+0x44 0x60 0x08 0xac

test/MC/Mips/micromips-control-instructions.s

 # CHECK-EL:    tlbr                       # encoding: [0x00,0x00,0x7c,0x13]
 # CHECK-EL:    tlbwi                      # encoding: [0x00,0x00,0x7c,0x23]
 # CHECK-EL:    tlbwr                      # encoding: [0x00,0x00,0x7c,0x33]
+# CHECK-EL:    lle $2, 8($4)              # encoding: [0x44,0x60,0x08,0x6c]
+# CHECK-EL:    sce $2, 8($4)              # encoding: [0x44,0x60,0x08,0xac]
 #------------------------------------------------------------------------------
 # Big endian
 #------------------------------------------------------------------------------

 # CHECK-EB:   tlbr                        # encoding: [0x00,0x00,0x13,0x7c]
 # CHECK-EB:   tlbwi                       # encoding: [0x00,0x00,0x23,0x7c]
 # CHECK-EB:   tlbwr                       # encoding: [0x00,0x00,0x33,0x7c]
+# CHECK-EB:   lle $2, 8($4)               # encoding: [0x60,0x44,0x6c,0x08]
+# CHECK-EB:   sce $2, 8($4)               # encoding: [0x60,0x44,0xac,0x08]
 
     sdbbp
     sdbbp 34

     tlbr
     tlbwi
     tlbwr
+    lle $2, 8($4)
+    sce $2, 8($4)