[mips][mips64r6] Add LDPC instruction

[zoran.jovanovic]

Summary

Initial support for ldpc instruction.

[vmedic]

I think we should have disassembler tests as we introduce decoder methods, other than that the patch looks good to me.

[dsanders]

We'll be able to do disassembler tests once D3760 and D3761 are reviewed and committed.

[zoran.jovanovic]

Closed by commit rL210460 (authored by zjovanovic).

lib/Target/Mips/Disassembler/MipsDisassembler.cpp

 static DecodeStatus DecodeExtSize(MCInst &Inst,
                                   unsigned Insn,
                                   uint64_t Address,
                                   const void *Decoder);
 
 static DecodeStatus DecodeSimm19Lsl2(MCInst &Inst, unsigned Insn,
                                      uint64_t Address, const void *Decoder);
 
+static DecodeStatus DecodeSimm18Lsl3(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>
 static DecodeStatus DecodeINSVE_DF(MCInst &MI, InsnType insn, uint64_t Address,
                                    const void *Decoder);
 namespace llvm {
 extern Target TheMipselTarget, TheMipsTarget, TheMips64Target,
               TheMips64elTarget;
static DecodeStatus DecodeExtSize(MCInst &Inst,
   return MCDisassembler::Success;
 }
 
 static DecodeStatus DecodeSimm19Lsl2(MCInst &Inst, unsigned Insn,
                                      uint64_t Address, const void *Decoder) {
   Inst.addOperand(MCOperand::CreateImm(SignExtend32<19>(Insn) << 2));
   return MCDisassembler::Success;
 }
+
+static DecodeStatus DecodeSimm18Lsl3(MCInst &Inst, unsigned Insn,
+                                     uint64_t Address, const void *Decoder) {
+  Inst.addOperand(MCOperand::CreateImm(SignExtend32<18>(Insn) << 3));
+  return MCDisassembler::Success;
+}

lib/Target/Mips/MCTargetDesc/MipsMCCodeEmitter.h

public:
   unsigned getLSAImmEncoding(const MCInst &MI, unsigned OpNo,
                              SmallVectorImpl<MCFixup> &Fixups,
                              const MCSubtargetInfo &STI) const;
 
   unsigned getSimm19Lsl2Encoding(const MCInst &MI, unsigned OpNo,
                                  SmallVectorImpl<MCFixup> &Fixups,
                                  const MCSubtargetInfo &STI) const;
 
+  unsigned getSimm18Lsl3Encoding(const MCInst &MI, unsigned OpNo,
+                                 SmallVectorImpl<MCFixup> &Fixups,
+                                 const MCSubtargetInfo &STI) const;
+
   unsigned getExprOpValue(const MCExpr *Expr, SmallVectorImpl<MCFixup> &Fixups,
                           const MCSubtargetInfo &STI) const;
 
 }; // class MipsMCCodeEmitter
 } // namespace llvm.
 
 #endif

lib/Target/Mips/MCTargetDesc/MipsMCCodeEmitter.cpp

MipsMCCodeEmitter::getSimm19Lsl2Encoding(const MCInst &MI, unsigned OpNo,
                                          const MCSubtargetInfo &STI) const {
   assert(MI.getOperand(OpNo).isImm());
   // The immediate is encoded as 'immediate << 2'.
   unsigned Res = getMachineOpValue(MI, MI.getOperand(OpNo), Fixups, STI);
   assert((Res & 3) == 0);
   return Res >> 2;
 }
 
+unsigned
+MipsMCCodeEmitter::getSimm18Lsl3Encoding(const MCInst &MI, unsigned OpNo,
+                                         SmallVectorImpl<MCFixup> &Fixups,
+                                         const MCSubtargetInfo &STI) const {
+  assert(MI.getOperand(OpNo).isImm());
+  // The immediate is encoded as 'immediate << 3'.
+  unsigned Res = getMachineOpValue(MI, MI.getOperand(OpNo), Fixups, STI);
+  assert((Res & 7) == 0);
+  return Res >> 3;
+}
+
 #include "MipsGenMCCodeEmitter.inc"

lib/Target/Mips/Mips32r6InstrFormats.td

 
 class OPCODE2<bits<2> Val> {
   bits<2> Value = Val;
 }
 def OPCODE2_ADDIUPC : OPCODE2<0b00>;
 def OPCODE2_LWPC    : OPCODE2<0b01>;
 def OPCODE2_LWUPC   : OPCODE2<0b10>;
 
+class OPCODE3<bits<3> Val> {
+  bits<3> Value = Val;
+}
+def OPCODE3_LDPC : OPCODE3<0b110>;
+
 class OPCODE5<bits<5> Val> {
   bits<5> Value = Val;
 }
 def OPCODE5_ALUIPC : OPCODE5<0b11111>;
 def OPCODE5_AUIPC  : OPCODE5<0b11110>;
 def OPCODE5_DAHI : OPCODE5<0b00110>;
 def OPCODE5_DATI : OPCODE5<0b11110>;
 
class PCREL19_FM<OPCODE2 Operation> : MipsR6Inst {
   bits<32> Inst;
 
   let Inst{31-26} = OPGROUP_PCREL.Value;
   let Inst{25-21} = rs;
   let Inst{20-19} = Operation.Value;
   let Inst{18-0} = imm;
 }
 
+class PCREL18_FM<OPCODE3 Operation> : MipsR6Inst {
+  bits<5> rs;
+  bits<18> imm;
+
+  bits<32> Inst;
+
+  let Inst{31-26} = OPGROUP_PCREL.Value;
+  let Inst{25-21} = rs;
+  let Inst{20-18} = Operation.Value;
+  let Inst{17-0} = imm;
+}
+
 class SPECIAL3_2R_FM<OPCODE6 Operation> : MipsR6Inst {
   bits<5> rd;
   bits<5> rt;
 
   bits<32> Inst;
 
   let Inst{31-26} = OPGROUP_SPECIAL3.Value;
   let Inst{25-21} = 0b00000;

lib/Target/Mips/Mips32r6InstrInfo.td

 }
 
 //===----------------------------------------------------------------------===//
 //
 // Instruction Descriptions
 //
 //===----------------------------------------------------------------------===//
 
-class PCREL19_DESC_BASE<string instr_asm, RegisterOperand GPROpnd> {
+class PCREL_DESC_BASE<string instr_asm, RegisterOperand GPROpnd,
+                      Operand ImmOpnd> {
   dag OutOperandList = (outs GPROpnd:$rs);
-  dag InOperandList = (ins simm19_lsl2:$imm);
+  dag InOperandList = (ins ImmOpnd:$imm);
   string AsmString = !strconcat(instr_asm, "\t$rs, $imm");
   list<dag> Pattern = [];
 }
 
-class ADDIUPC_DESC : PCREL19_DESC_BASE<"addiupc", GPR32Opnd>;
-class LWPC_DESC: PCREL19_DESC_BASE<"lwpc", GPR32Opnd>;
-class LWUPC_DESC: PCREL19_DESC_BASE<"lwupc", GPR32Opnd>;
+class ADDIUPC_DESC : PCREL_DESC_BASE<"addiupc", GPR32Opnd, simm19_lsl2>;
+class LWPC_DESC: PCREL_DESC_BASE<"lwpc", GPR32Opnd, simm19_lsl2>;
+class LWUPC_DESC: PCREL_DESC_BASE<"lwupc", GPR32Opnd, simm19_lsl2>;
 
 class ALIGN_DESC_BASE<string instr_asm, RegisterOperand GPROpnd,
                       Operand ImmOpnd> {
   dag OutOperandList = (outs GPROpnd:$rd);
   dag InOperandList = (ins GPROpnd:$rs, GPROpnd:$rt, ImmOpnd:$bp);
   string AsmString = !strconcat(instr_asm, "\t$rd, $rs, $rt, $bp");
   list<dag> Pattern = [];
 }

lib/Target/Mips/Mips64r6InstrInfo.td

 class DDIV_ENC    : SPECIAL_3R_FM<0b00010, 0b011110>;
 class DDIVU_ENC   : SPECIAL_3R_FM<0b00010, 0b011111>;
 class DMOD_ENC    : SPECIAL_3R_FM<0b00011, 0b011110>;
 class DMODU_ENC   : SPECIAL_3R_FM<0b00011, 0b011111>;
 class DMUH_ENC    : SPECIAL_3R_FM<0b00011, 0b111000>;
 class DMUHU_ENC   : SPECIAL_3R_FM<0b00011, 0b111001>;
 class DMUL_R6_ENC : SPECIAL_3R_FM<0b00010, 0b111000>;
 class DMULU_ENC   : SPECIAL_3R_FM<0b00010, 0b111001>;
+class LDPC_ENC    : PCREL18_FM<OPCODE3_LDPC>;
 
 //===----------------------------------------------------------------------===//
 //
 // Instruction Descriptions
 //
 //===----------------------------------------------------------------------===//
 
 class DALIGN_DESC  : ALIGN_DESC_BASE<"dalign", GPR64Opnd, uimm3>;
 class DAHI_DESC    : AUI_DESC_BASE<"dahi", GPR64Opnd>;
 class DATI_DESC    : AUI_DESC_BASE<"dati", GPR64Opnd>;
 class DAUI_DESC    : AUI_DESC_BASE<"daui", GPR64Opnd>;
 class DBITSWAP_DESC : BITSWAP_DESC_BASE<"dbitswap", GPR64Opnd>;
 class DDIV_DESC    : DIVMOD_DESC_BASE<"ddiv", GPR64Opnd>;
 class DDIVU_DESC   : DIVMOD_DESC_BASE<"ddivu", GPR64Opnd>;
 class DMOD_DESC    : DIVMOD_DESC_BASE<"dmod", GPR64Opnd>;
 class DMODU_DESC   : DIVMOD_DESC_BASE<"dmodu", GPR64Opnd>;
 class DMUH_DESC    : MUL_R6_DESC_BASE<"dmuh", GPR64Opnd>;
 class DMUHU_DESC   : MUL_R6_DESC_BASE<"dmuhu", GPR64Opnd>;
 class DMUL_R6_DESC : MUL_R6_DESC_BASE<"dmul", GPR64Opnd>;
 class DMULU_DESC   : MUL_R6_DESC_BASE<"dmulu", GPR64Opnd>;
+class LDPC_DESC    : PCREL_DESC_BASE<"ldpc", GPR64Opnd, simm18_lsl3>;
 
 //===----------------------------------------------------------------------===//
 //
 // Instruction Definitions
 //
 //===----------------------------------------------------------------------===//
 
 def DAHI : DAHI_ENC, DAHI_DESC, ISA_MIPS64R6;
 def DALIGN : DALIGN_ENC, DALIGN_DESC, ISA_MIPS64R6;
 def DATI : DATI_ENC, DATI_DESC, ISA_MIPS64R6;
 def DAUI : DAUI_ENC, DAUI_DESC, ISA_MIPS64R6;
 def DBITSWAP : DBITSWAP_ENC, DBITSWAP_DESC, ISA_MIPS64R6;
 def DDIV : DDIV_ENC, DDIV_DESC, ISA_MIPS64R6;
 def DDIVU : DDIVU_ENC, DDIVU_DESC, ISA_MIPS64R6;
 // def DLSA; // See MSA
 def DMOD : DMOD_ENC, DMOD_DESC, ISA_MIPS64R6;
 def DMODU : DMODU_ENC, DMODU_DESC, ISA_MIPS64R6;
 def DMUH: DMUH_ENC, DMUH_DESC, ISA_MIPS64R6;
 def DMUHU: DMUHU_ENC, DMUHU_DESC, ISA_MIPS64R6;
 def DMUL_R6: DMUL_R6_ENC, DMUL_R6_DESC, ISA_MIPS64R6;
 def DMULU: DMULU_ENC, DMULU_DESC, ISA_MIPS64R6;
-def LDPC;
+def LDPC: LDPC_ENC, LDPC_DESC, ISA_MIPS64R6;

lib/Target/Mips/MipsCodeEmitter.cpp

private:
   unsigned getBranchTargetOpValue(const MachineInstr &MI, unsigned OpNo) const;
   unsigned getMemEncoding(const MachineInstr &MI, unsigned OpNo) const;
   unsigned getMemEncodingMMImm12(const MachineInstr &MI, unsigned OpNo) const;
   unsigned getMSAMemEncoding(const MachineInstr &MI, unsigned OpNo) const;
   unsigned getSizeExtEncoding(const MachineInstr &MI, unsigned OpNo) const;
   unsigned getSizeInsEncoding(const MachineInstr &MI, unsigned OpNo) const;
   unsigned getLSAImmEncoding(const MachineInstr &MI, unsigned OpNo) const;
   unsigned getSimm19Lsl2Encoding(const MachineInstr &MI, unsigned OpNo) const;
+  unsigned getSimm18Lsl3Encoding(const MachineInstr &MI, unsigned OpNo) const;
 
   /// Expand pseudo instructions with accumulator register operands.
   void expandACCInstr(MachineBasicBlock::instr_iterator MI,
                       MachineBasicBlock &MBB, unsigned Opc) const;
 
   /// \brief Expand pseudo instruction. Return true if MI was expanded.
   bool expandPseudos(MachineBasicBlock::instr_iterator &MI,
                      MachineBasicBlock &MBB) const;

 }
 
 unsigned MipsCodeEmitter::getSimm19Lsl2Encoding(const MachineInstr &MI,
                                                 unsigned OpNo) const {
   llvm_unreachable("Unimplemented function.");
   return 0;
 }
 
+unsigned MipsCodeEmitter::getSimm18Lsl3Encoding(const MachineInstr &MI,
+                                                unsigned OpNo) const {
+  llvm_unreachable("Unimplemented function.");
+  return 0;
+}
+
 /// getMachineOpValue - Return binary encoding of operand. If the machine
 /// operand requires relocation, record the relocation and return zero.
 unsigned MipsCodeEmitter::getMachineOpValue(const MachineInstr &MI,
                                             const MachineOperand &MO) const {
   if (MO.isReg())
     return TM.getRegisterInfo()->getEncodingValue(MO.getReg());
   else if (MO.isImm())
     return static_cast<unsigned>(MO.getImm());

lib/Target/Mips/MipsInstrInfo.td

def simm16      : Operand<i32> {
   let DecoderMethod= "DecodeSimm16";
 }
 
 def simm19_lsl2 : Operand<i32> {
   let EncoderMethod = "getSimm19Lsl2Encoding";
   let DecoderMethod = "DecodeSimm19Lsl2";
 }
 
+def simm18_lsl3 : Operand<i32> {
+  let EncoderMethod = "getSimm18Lsl3Encoding";
+  let DecoderMethod = "DecodeSimm18Lsl3";
+}
+
 def simm20      : Operand<i32> {
 }
 
 def uimm20      : Operand<i32> {
 }
 
 def uimm10      : Operand<i32> {
 }

test/MC/Mips/mips64r6/valid.s

# RUN: llvm-mc %s -triple=mips-unknown-linux -show-encoding -mcpu=mips64r6 | FileCheck %s
         dmod    $2,$3,$4         # CHECK: dmod $2, $3, $4  # encoding: [0x00,0x64,0x10,0xde]
         dmodu   $2,$3,$4         # CHECK: dmodu $2, $3, $4 # encoding: [0x00,0x64,0x10,0xdf]
         dmul    $2,$3,$4         # CHECK: dmul $2, $3, $4  # encoding: [0x00,0x64,0x10,0xb8]
         dmuh    $2,$3,$4         # CHECK: dmuh $2, $3, $4  # encoding: [0x00,0x64,0x10,0xf8]
         dmulu   $2,$3,$4         # CHECK: dmulu $2, $3, $4 # encoding: [0x00,0x64,0x10,0xb9]
         dmuhu   $2,$3,$4         # CHECK: dmuhu $2, $3, $4 # encoding: [0x00,0x64,0x10,0xf9]
         jialc   $5, 256          # CHECK: jialc $5, 256    # encoding: [0xf8,0x05,0x01,0x00]
         jic     $5, 256          # CHECK: jic $5, 256      # encoding: [0xd8,0x05,0x01,0x00]
+        ldpc    $2,123456        # CHECK: ldpc $2, 123456  # encoding: [0xec,0x58,0x3c,0x48]
         lwpc    $2,268           # CHECK: lwpc $2, 268     # encoding: [0xec,0x48,0x00,0x43]
         lwupc   $2,268           # CHECK: lwupc $2, 268    # encoding: [0xec,0x50,0x00,0x43]
         maddf.s $f2,$f3,$f4      # CHECK: maddf.s $f2, $f3, $f4  # encoding: [0x46,0x04,0x18,0x98]
         maddf.d $f2,$f3,$f4      # CHECK: maddf.d $f2, $f3, $f4  # encoding: [0x46,0x24,0x18,0x98]
         max.s   $f0, $f2, $f4    # CHECK: max.s $f0, $f2, $f4 # encoding: [0x46,0x04,0x10,0x1d]
         max.d   $f0, $f2, $f4    # CHECK: max.d $f0, $f2, $f4 # encoding: [0x46,0x24,0x10,0x1d]
         min.s   $f0, $f2, $f4    # CHECK: min.s $f0, $f2, $f4 # encoding: [0x46,0x04,0x10,0x1c]
         min.d   $f0, $f2, $f4    # CHECK: min.d $f0, $f2, $f4 # encoding: [0x46,0x24,0x10,0x1c]