[mips][microMIPS] Implement CACHEE and PREFE instructions

[hvarga]

Summary

The patch implements microMIPS CACHEE and PREFE instructions.

[dsanders]

LGTM with some nits.

lib/Target/Mips/MCTargetDesc/MipsMCCodeEmitter.cpp

773–774

Indentation

lib/Target/Mips/MCTargetDesc/MipsMCCodeEmitter.h

176–177

Indentation

lib/Target/Mips/MicroMipsInstrFormats.td

925

This doesn't follow the naming convention but that's ok since microMIPS in general hasn't migrated yet.

lib/Target/Mips/MicroMipsInstrInfo.td

110

Shouldn't it be simm9?

lib/Target/Mips/Disassembler/MipsDisassembler.cpp

static DecodeStatus DecodeCacheOpR6(MCInst &Inst,
                                     uint64_t Address,
                                     const void *Decoder);
 
 static DecodeStatus DecodeCacheOpMM(MCInst &Inst,
                                     unsigned Insn,
                                     uint64_t Address,
                                     const void *Decoder);
 
+static DecodeStatus DecodePrefeOpMM(MCInst &Inst,
+                                    unsigned Insn,
+                                    uint64_t Address,
+                                    const void *Decoder);
+
 static DecodeStatus DecodeSyncI(MCInst &Inst,
                                 unsigned Insn,
                                 uint64_t Address,
                                 const void *Decoder);
 
 static DecodeStatus DecodeMSA128Mem(MCInst &Inst, unsigned Insn,
                                     uint64_t Address, const void *Decoder);
 
static DecodeStatus DecodeCacheOpMM(MCInst &Inst,
 
   Inst.addOperand(MCOperand::createReg(Base));
   Inst.addOperand(MCOperand::createImm(Offset));
   Inst.addOperand(MCOperand::createImm(Hint));
 
   return MCDisassembler::Success;
 }
 
+static DecodeStatus DecodePrefeOpMM(MCInst &Inst,
+                                    unsigned Insn,
+                                    uint64_t Address,
+                                    const void *Decoder) {
+  int Offset = SignExtend32<9>(Insn & 0x1ff);
+  unsigned Base = fieldFromInstruction(Insn, 16, 5);
+  unsigned Hint = fieldFromInstruction(Insn, 21, 5);
+
+  Base = getReg(Decoder, Mips::GPR32RegClassID, Base);
+
+  Inst.addOperand(MCOperand::createReg(Base));
+  Inst.addOperand(MCOperand::createImm(Offset));
+  Inst.addOperand(MCOperand::createImm(Hint));
+
+  return MCDisassembler::Success;
+}
+
 static DecodeStatus DecodeCacheOpR6(MCInst &Inst,
                                     unsigned Insn,
                                     uint64_t Address,
                                     const void *Decoder) {
   int Offset = fieldFromInstruction(Insn, 7, 9);
   unsigned Hint = fieldFromInstruction(Insn, 16, 5);
   unsigned Base = fieldFromInstruction(Insn, 21, 5);
 

lib/Target/Mips/MCTargetDesc/MipsMCCodeEmitter.h

unsigned getMemEncodingMMImm4Lsl2(const MCInst &MI, unsigned OpNo,
                                     SmallVectorImpl<MCFixup> &Fixups,
                                     const MCSubtargetInfo &STI) const;
   unsigned getMemEncodingMMSPImm5Lsl2(const MCInst &MI, unsigned OpNo,
                                       SmallVectorImpl<MCFixup> &Fixups,
                                       const MCSubtargetInfo &STI) const;
   unsigned getMemEncodingMMGPImm7Lsl2(const MCInst &MI, unsigned OpNo,
                                       SmallVectorImpl<MCFixup> &Fixups,
                                       const MCSubtargetInfo &STI) const;
+  unsigned getMemEncodingMMImm9(const MCInst &MI, unsigned OpNo,
+                                 SmallVectorImpl<MCFixup> &Fixups,
+                                 const MCSubtargetInfo &STI) const;
   unsigned getMemEncodingMMImm12(const MCInst &MI, unsigned OpNo,
                                  SmallVectorImpl<MCFixup> &Fixups,
                                  const MCSubtargetInfo &STI) const;
   unsigned getMemEncodingMMImm4sp(const MCInst &MI, unsigned OpNo,
                                   SmallVectorImpl<MCFixup> &Fixups,
                                   const MCSubtargetInfo &STI) const;
   unsigned getSizeExtEncoding(const MCInst &MI, unsigned OpNo,
                               SmallVectorImpl<MCFixup> &Fixups,

lib/Target/Mips/MCTargetDesc/MipsMCCodeEmitter.cpp

getMemEncodingMMGPImm7Lsl2(const MCInst &MI, unsigned OpNo,
 
   unsigned OffBits = getMachineOpValue(MI, MI.getOperand(OpNo+1),
                                        Fixups, STI) >> 2;
 
   return OffBits & 0x7F;
 }
 
 unsigned MipsMCCodeEmitter::
+getMemEncodingMMImm9(const MCInst &MI, unsigned OpNo,
+                      SmallVectorImpl<MCFixup> &Fixups,
+                      const MCSubtargetInfo &STI) const {
+  // Base register is encoded in bits 20-16, offset is encoded in bits 11-0.
+  assert(MI.getOperand(OpNo).isReg());
+  unsigned RegBits = getMachineOpValue(MI, MI.getOperand(OpNo), Fixups, STI) << 16;
+  unsigned OffBits = getMachineOpValue(MI, MI.getOperand(OpNo+1), Fixups, STI);
+
+  return (OffBits & 0x1FF) | RegBits;
+}
+
+unsigned MipsMCCodeEmitter::
 getMemEncodingMMImm12(const MCInst &MI, unsigned OpNo,
                       SmallVectorImpl<MCFixup> &Fixups,
                       const MCSubtargetInfo &STI) const {
   // opNum can be invalid if instruction had reglist as operand.
   // MemOperand is always last operand of instruction (base + offset).
   switch (MI.getOpcode()) {
   default:
     break;

lib/Target/Mips/MicroMipsInstrFormats.td

class CACHE_PREF_FM_MM<bits<6> op, bits<4> funct> : MMArch {
 
   let Inst{31-26} = op;
   let Inst{25-21} = hint;
   let Inst{20-16} = base;
   let Inst{15-12} = funct;
   let Inst{11-0}  = offset;
 }
 
+class CACHE_PREFE_FM_MM<bits<6> op, bits<3> funct> : MMArch {
+  bits<21> addr;
+  bits<5> hint;
+  bits<5> base = addr{20-16};
+  bits<9> offset = addr{8-0};
+
+  bits<32> Inst;
+
+  let Inst{31-26} = op;
+  let Inst{25-21} = hint;
+  let Inst{20-16} = base;
+  let Inst{15-12} = 0xA;
+  let Inst{11-9} = funct;
+  let Inst{8-0}  = offset;
+}
+
 class BARRIER_FM_MM<bits<5> op> : MMArch {
   bits<32> Inst;
 
   let Inst{31-26} = 0x0;
   let Inst{25-21} = 0x0;
   let Inst{20-16} = 0x0;
   let Inst{15-11} = op;
   let Inst{10-6}  = 0x0;

lib/Target/Mips/MicroMipsInstrInfo.td

 
 def mem_mm_gp_imm7_lsl2 : Operand<i32> {
   let PrintMethod = "printMemOperand";
   let MIOperandInfo = (ops GPRMM16:$base, simm7:$offset);
   let OperandType = "OPERAND_MEMORY";
   let EncoderMethod = "getMemEncodingMMGPImm7Lsl2";
 }
 
+def mem_mm_9 : Operand<i32> {
+  let PrintMethod = "printMemOperand";
+  let MIOperandInfo = (ops GPR32, simm12);
+  let EncoderMethod = "getMemEncodingMMImm9";
+  let ParserMatchClass = MipsMemAsmOperand;
+  let OperandType = "OPERAND_MEMORY";
+}
+
 def mem_mm_12 : Operand<i32> {
   let PrintMethod = "printMemOperand";
   let MIOperandInfo = (ops GPR32, simm12);
   let EncoderMethod = "getMemEncodingMMImm12";
   let ParserMatchClass = MipsMemAsmOperand;
   let OperandType = "OPERAND_MEMORY";
 }
 
let DecoderNamespace = "MicroMips", Predicates = [InMicroMips] in {
   def SC_MM : SCBaseMM<"sc", GPR32Opnd>, LL_FM_MM<0xb>;
 
   let DecoderMethod = "DecodeCacheOpMM" in {
   def CACHE_MM : MMRel, CacheOp<"cache", mem_mm_12>,
                  CACHE_PREF_FM_MM<0x08, 0x6>;
   def PREF_MM  : MMRel, CacheOp<"pref", mem_mm_12>,
                  CACHE_PREF_FM_MM<0x18, 0x2>;
   }
+
+  let DecoderMethod = "DecodePrefeOpMM" in {
+    def PREFE_MM  : MMRel, CacheOp<"prefe", mem_mm_9>,
+                 CACHE_PREFE_FM_MM<0x18, 0x2>;
+    def CACHEE_MM : MMRel, CacheOp<"cachee", mem_mm_9>,
+                 CACHE_PREFE_FM_MM<0x18, 0x3>;
+  }
   def SSNOP_MM : MMRel, Barrier<"ssnop">, BARRIER_FM_MM<0x1>;
   def EHB_MM   : MMRel, Barrier<"ehb">, BARRIER_FM_MM<0x3>;
   def PAUSE_MM : MMRel, Barrier<"pause">, BARRIER_FM_MM<0x5>;
 
   def TLBP_MM : MMRel, TLB<"tlbp">, COP0_TLB_FM_MM<0x0d>;
   def TLBR_MM : MMRel, TLB<"tlbr">, COP0_TLB_FM_MM<0x4d>;
   def TLBWI_MM : MMRel, TLB<"tlbwi">, COP0_TLB_FM_MM<0x8d>;
   def TLBWR_MM : MMRel, TLB<"tlbwr">, COP0_TLB_FM_MM<0xcd>;

test/MC/Disassembler/Mips/micromips.txt

 
 0x46 0xce # CHECK: sdbbp16 14
 
 0x84 0x34 # CHECK: movep $5, $6, $2, $3
 
 0x00 0x00 0x57 0x7c # CHECK: ei
 
 0x00 0x0a 0x57 0x7c # CHECK: ei $10
+
+0x60 0x25 0xa6 0x08 # CHECK: cachee 1, 8($5)
+
+0x60 0x25 0xa4 0x08 # CHECK: prefe 1, 8($5)

test/MC/Disassembler/Mips/micromips_le.txt

 
 0xce 0x46 # CHECK: sdbbp16 14
 
 0x34 0x84 # CHECK: movep $5, $6, $2, $3
 
 0x00 0x00 0x7c 0x57 # CHECK: ei
 
 0x0a 0x00 0x7c 0x57 # CHECK: ei $10
+
+0x25 0x60 0x08 0xa6 # CHECK: cachee 1, 8($5)
+
+0x25 0x60 0x08 0xa4 # CHECK: prefe 1, 8($5)

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

 # CHECK-EL:    ei                         # encoding: [0x00,0x00,0x7c,0x57]
 # CHECK-EL:    ei  $10                    # encoding: [0x0a,0x00,0x7c,0x57]
 # CHECK-EL:    wait                       # encoding: [0x00,0x00,0x7c,0x93]
 # CHECK-EL:    wait 17                    # encoding: [0x11,0x00,0x7c,0x93]
 # CHECK-EL:    tlbp                       # encoding: [0x00,0x00,0x7c,0x03]
 # 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:    prefe 1, 8($5)             # encoding: [0x25,0x60,0x08,0xa4]
+# CHECK-EL:    cachee 1, 8($5)            # encoding: [0x25,0x60,0x08,0xa6]
 #------------------------------------------------------------------------------
 # Big endian
 #------------------------------------------------------------------------------
 # CHECK-EB:   sdbbp                       # encoding: [0x00,0x00,0xdb,0x7c]
 # CHECK-EB:   sdbbp 34                    # encoding: [0x00,0x22,0xdb,0x7c]
 # CHECK-EB:   .set push
 # CHECK-EB:   .set mips32r2
 # CHECK-EB:   rdhwr $5, $29

 # CHECK-EB:   ei                          # encoding: [0x00,0x00,0x57,0x7c]
 # CHECK-EB:   ei  $10                     # encoding: [0x00,0x0a,0x57,0x7c]
 # CHECK-EB:   wait                        # encoding: [0x00,0x00,0x93,0x7c]
 # CHECK-EB:   wait 17                     # encoding: [0x00,0x11,0x93,0x7c]
 # CHECK-EB:   tlbp                        # encoding: [0x00,0x00,0x03,0x7c]
 # 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:   prefe 1, 8($5)              # encoding: [0x60,0x25,0xa4,0x08]
+# CHECK-EB:   cachee 1, 8($5)             # encoding: [0x60,0x25,0xa6,0x08]
 
     sdbbp
     sdbbp 34
     rdhwr $5, $29
     cache 1, 8($5)
     pref 1, 8($5)
     ssnop
     ehb
# CHECK-EB:   cachee 1, 8($5)             # encoding: [0x60,0x25,0xa6,0x08]
     ei $0
     ei $10
     wait
     wait 17
     tlbp
     tlbr
     tlbwi
     tlbwr
+    prefe 1, 8($5)
+    cachee 1, 8($5)