[mips][microMIPS] Implement BEQZC and BNEZC instructions

[dsanders]

lib/Target/Mips/Disassembler/MipsDisassembler.cpp

1842–1844

Indentation

lib/Target/Mips/MCTargetDesc/MipsMCCodeEmitter.cpp

333–336

Formatting

346

Shouldn't this be filled in? The previous patch (D15526) added the necessary fixup.

Could you also add a test case covering this path?

lib/Target/Mips/MCTargetDesc/MipsMCCodeEmitter.h

137–138

Indentation

[zoran.jovanovic]

lib/Target/Mips/MCTargetDesc/MipsMCCodeEmitter.cpp

346

This patch is first patch and patch D15526 depends on this one.
D15526 adds necessary fixup and contains corresponding test cases.

[zoran.jovanovic]

New patch version.
Patch rebased and formatting comments addressed.

[sdardis]

LGTM.

[dsanders]

LGTM. Sorry for the delay.

lib/Target/Mips/Disassembler/MipsDisassembler.cpp

static DecodeStatus DecodeJumpTarget(MCInst &Inst,
                                      uint64_t Address,
                                      const void *Decoder);
 
 static DecodeStatus DecodeBranchTarget21(MCInst &Inst,
                                          unsigned Offset,
                                          uint64_t Address,
                                          const void *Decoder);
 
+static DecodeStatus DecodeBranchTarget21MM(MCInst &Inst,
+                                           unsigned Offset,
+                                           uint64_t Address,
+                                           const void *Decoder);
+
 static DecodeStatus DecodeBranchTarget26(MCInst &Inst,
                                          unsigned Offset,
                                          uint64_t Address,
                                          const void *Decoder);
 
 // DecodeBranchTarget7MM - Decode microMIPS branch offset, which is
 // shifted left by 1 bit.
 static DecodeStatus DecodeBranchTarget7MM(MCInst &Inst,
static DecodeStatus DecodeBranchTarget21(MCInst &Inst,
                                          uint64_t Address,
                                          const void *Decoder) {
   int32_t BranchOffset = SignExtend32<21>(Offset) * 4;
 
   Inst.addOperand(MCOperand::createImm(BranchOffset));
   return MCDisassembler::Success;
 }
 
+static DecodeStatus DecodeBranchTarget21MM(MCInst &Inst,
+  unsigned Offset,
+  uint64_t Address,
+  const void *Decoder) {
+  int32_t BranchOffset = SignExtend32<21>(Offset) << 1;
+
+  Inst.addOperand(MCOperand::createImm(BranchOffset));
+  return MCDisassembler::Success;
+}
+
 static DecodeStatus DecodeBranchTarget26(MCInst &Inst,
                                          unsigned Offset,
                                          uint64_t Address,
                                          const void *Decoder) {
   int32_t BranchOffset = SignExtend32<26>(Offset) * 4;
 
   Inst.addOperand(MCOperand::createImm(BranchOffset));
   return MCDisassembler::Success;

lib/Target/Mips/MCTargetDesc/MipsMCCodeEmitter.h

public:
 
   // getBranchTarget21OpValue - Return binary encoding of the branch
   // offset operand. If the machine operand requires relocation,
   // record the relocation and return zero.
   unsigned getBranchTarget21OpValue(const MCInst &MI, unsigned OpNo,
                                    SmallVectorImpl<MCFixup> &Fixups,
                                    const MCSubtargetInfo &STI) const;
 
+  // getBranchTarget21OpValueMM - Return binary encoding of the branch
+  // offset operand for microMIPS. If the machine operand requires
+  // relocation,record the relocation and return zero.
+  unsigned getBranchTarget21OpValueMM(const MCInst &MI, unsigned OpNo,
+    SmallVectorImpl<MCFixup> &Fixups,
+    const MCSubtargetInfo &STI) const;
+
   // getBranchTarget26OpValue - Return binary encoding of the branch
   // offset operand. If the machine operand requires relocation,
   // record the relocation and return zero.
   unsigned getBranchTarget26OpValue(const MCInst &MI, unsigned OpNo,
                                     SmallVectorImpl<MCFixup> &Fixups,
                                     const MCSubtargetInfo &STI) const;
 
   // getBranchTarget26OpValueMM - Return binary encoding of the branch

lib/Target/Mips/MCTargetDesc/MipsMCCodeEmitter.cpp

getBranchTarget21OpValue(const MCInst &MI, unsigned OpNo,
 
   const MCExpr *FixupExpression = MCBinaryExpr::createAdd(
       MO.getExpr(), MCConstantExpr::create(-4, Ctx), Ctx);
   Fixups.push_back(MCFixup::create(0, FixupExpression,
                                    MCFixupKind(Mips::fixup_MIPS_PC21_S2)));
   return 0;
 }
 
+/// getBranchTarget21OpValueMM - Return binary encoding of the branch
+/// target operand for microMIPS. If the machine operand requires
+/// relocation, record the relocation and return zero.
+unsigned MipsMCCodeEmitter::
+getBranchTarget21OpValueMM(const MCInst &MI, unsigned OpNo,
+SmallVectorImpl<MCFixup> &Fixups,
+const MCSubtargetInfo &STI) const {
+
+  const MCOperand &MO = MI.getOperand(OpNo);
+
+  // If the destination is an immediate, divide by 2.
+  if (MO.isImm()) return MO.getImm() >> 1;
+
+  assert(MO.isExpr() &&
+    "getBranchTarget21OpValueMM expects only expressions or immediates");
+
+  // TODO: Push fixup.
+  return 0;
+}
+
 /// getBranchTarget26OpValue - Return binary encoding of the branch
 /// target operand. If the machine operand requires relocation,
 /// record the relocation and return zero.
 unsigned MipsMCCodeEmitter::
 getBranchTarget26OpValue(const MCInst &MI, unsigned OpNo,
                          SmallVectorImpl<MCFixup> &Fixups,
                          const MCSubtargetInfo &STI) const {
 

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 CMP_BRANCH_OFF21_FM_MMR6<string opstr, bits<6> funct> : MipsR6Inst {
+  bits<5> rs;
+  bits<21> offset;
+
+  bits<32> Inst;
+
+  let Inst{31-26} = funct;
+  let Inst{25-21} = rs;
+  let Inst{20-0} = offset;
+}

lib/Target/Mips/MicroMips32r6InstrInfo.td

 //=- MicroMips32r6InstrInfo.td - MicroMips r6 Instruction Information -*- tablegen -*-=//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // This file describes microMIPSr6 instructions.
 //
 //===----------------------------------------------------------------------===//
 
+def brtarget21_mm : Operand<OtherVT> {
+  let EncoderMethod = "getBranchTarget21OpValueMM";
+  let OperandType = "OPERAND_PCREL";
+  let DecoderMethod = "DecodeBranchTarget21MM";
+  let ParserMatchClass = MipsJumpTargetAsmOperand;
+}
+
 def brtarget26_mm : Operand<OtherVT> {
   let EncoderMethod = "getBranchTarget26OpValueMM";
   let OperandType = "OPERAND_PCREL";
   let DecoderMethod = "DecodeBranchTarget26MM";
   let ParserMatchClass = MipsJumpTargetAsmOperand;
 }
 
 //===----------------------------------------------------------------------===//

 class AUI_MMR6_ENC : AUI_FM_MMR6;
 class BALC_MMR6_ENC  : BRANCH_OFF26_FM<0b101101>;
 class BC_MMR6_ENC : BRANCH_OFF26_FM<0b100101>;
 class BC16_MMR6_ENC : BC16_FM_MM16R6;
 class BEQZC16_MMR6_ENC : BEQZC_BNEZC_FM_MM16R6<0x23>;
 class BNEZC16_MMR6_ENC : BEQZC_BNEZC_FM_MM16R6<0x2b>;
 class BITSWAP_MMR6_ENC : POOL32A_BITSWAP_FM_MMR6<0b101100>;
 class BRK_MMR6_ENC : BREAK_MMR6_ENC<"break">;
+class BEQZC_MMR6_ENC : CMP_BRANCH_OFF21_FM_MMR6<"beqzc", 0b100000>;
+class BNEZC_MMR6_ENC : CMP_BRANCH_OFF21_FM_MMR6<"bnezc", 0b101000>;
 class BEQZALC_MMR6_ENC : CMP_BRANCH_1R_RT_OFF16_FM_MMR6<0b011101>;
 class BNEZALC_MMR6_ENC : CMP_BRANCH_1R_RT_OFF16_FM_MMR6<0b011111>;
 class BGTZALC_MMR6_ENC : CMP_BRANCH_1R_RT_OFF16_FM_MMR6<0b111000>;
 class BLTZALC_MMR6_ENC : CMP_BRANCH_1R_BOTH_OFF16_FM_MMR6<0b111000>;
 class BGEZALC_MMR6_ENC : CMP_BRANCH_1R_BOTH_OFF16_FM_MMR6<0b110000>;
 class BLEZALC_MMR6_ENC : CMP_BRANCH_1R_RT_OFF16_FM_MMR6<0b110000>;
 class CACHE_MMR6_ENC : CACHE_PREF_FM_MMR6<0b001000, 0b0110>;
 class CLO_MMR6_ENC : POOL32A_2R_FM_MMR6<0b0100101100>;

 class SWSP_MMR6_DESC
     : MicroMipsInst16<(outs), (ins GPR32Opnd:$rt, mem_mm_sp_imm5_lsl2:$offset),
                       !strconcat("sw", "\t$rt, $offset"), [], II_SW, FrmI>,
       MMR6Arch<"sw">, MicroMipsR6Inst16 {
   let DecoderMethod = "DecodeMemMMSPImm5Lsl2";
   let mayStore = 1;
 }
 
+class BEQZC_MMR6_DESC
+    : CMP_CBR_EQNE_Z_DESC_BASE<"beqzc", brtarget21_mm, GPR32Opnd>,
+      MMR6Arch<"beqzc">;
+class BNEZC_MMR6_DESC
+    : CMP_CBR_EQNE_Z_DESC_BASE<"bnezc", brtarget21_mm, GPR32Opnd>,
+      MMR6Arch<"bnezc">;
+
 //===----------------------------------------------------------------------===//
 //
 // Instruction Definitions
 //
 //===----------------------------------------------------------------------===//
 
 let DecoderNamespace = "MicroMipsR6" in {
 def ADD_MMR6 : StdMMR6Rel, ADD_MMR6_DESC, ADD_MMR6_ENC, ISA_MICROMIPS32R6;
 def ADDIU_MMR6 : StdMMR6Rel, ADDIU_MMR6_DESC, ADDIU_MMR6_ENC, ISA_MICROMIPS32R6;
 def ADDU_MMR6 : StdMMR6Rel, ADDU_MMR6_DESC, ADDU_MMR6_ENC, ISA_MICROMIPS32R6;
 def ADDIUPC_MMR6 : R6MMR6Rel, ADDIUPC_MMR6_ENC, ADDIUPC_MMR6_DESC,
                    ISA_MICROMIPS32R6;
 def ALUIPC_MMR6 : R6MMR6Rel, ALUIPC_MMR6_ENC, ALUIPC_MMR6_DESC,
                   ISA_MICROMIPS32R6;
 def AND_MMR6 : StdMMR6Rel, AND_MMR6_DESC, AND_MMR6_ENC, ISA_MICROMIPS32R6;
 def ANDI_MMR6 : StdMMR6Rel, ANDI_MMR6_DESC, ANDI_MMR6_ENC, ISA_MICROMIPS32R6;
 def AUIPC_MMR6 : R6MMR6Rel, AUIPC_MMR6_ENC, AUIPC_MMR6_DESC, ISA_MICROMIPS32R6;
 def ALIGN_MMR6 : R6MMR6Rel, ALIGN_MMR6_ENC, ALIGN_MMR6_DESC, ISA_MICROMIPS32R6;
 def AUI_MMR6 : R6MMR6Rel, AUI_MMR6_ENC, AUI_MMR6_DESC, ISA_MICROMIPS32R6;
 def BALC_MMR6 : R6MMR6Rel, BALC_MMR6_ENC, BALC_MMR6_DESC, ISA_MICROMIPS32R6;
 def BC_MMR6 : R6MMR6Rel, BC_MMR6_ENC, BC_MMR6_DESC, ISA_MICROMIPS32R6;
 def BC16_MMR6 : StdMMR6Rel, BC16_MMR6_DESC, BC16_MMR6_ENC, ISA_MICROMIPS32R6;
+def BEQZC_MMR6 : R6MMR6Rel, BEQZC_MMR6_ENC, BEQZC_MMR6_DESC,
+                 ISA_MICROMIPS32R6;
 def BEQZC16_MMR6 : StdMMR6Rel, BEQZC16_MMR6_DESC, BEQZC16_MMR6_ENC,
                    ISA_MICROMIPS32R6;
+def BNEZC_MMR6 : R6MMR6Rel, BNEZC_MMR6_ENC, BNEZC_MMR6_DESC,
+                 ISA_MICROMIPS32R6;
 def BNEZC16_MMR6 : StdMMR6Rel, BNEZC16_MMR6_DESC, BNEZC16_MMR6_ENC,
                    ISA_MICROMIPS32R6;
 def BITSWAP_MMR6 : R6MMR6Rel, BITSWAP_MMR6_ENC, BITSWAP_MMR6_DESC,
                    ISA_MICROMIPS32R6;
 def BEQZALC_MMR6 : R6MMR6Rel, BEQZALC_MMR6_ENC, BEQZALC_MMR6_DESC,
                    ISA_MICROMIPS32R6;
 def BGEZALC_MMR6 : R6MMR6Rel, BGEZALC_MMR6_ENC, BGEZALC_MMR6_DESC,
                    ISA_MICROMIPS32R6;

lib/Target/Mips/Mips32r6InstrInfo.td

class CMP_BC_DESC_BASE<string instr_asm, DAGOperand opnd,
                        RegisterOperand GPROpnd> : BRANCH_DESC_BASE {
   dag InOperandList = (ins GPROpnd:$rs, GPROpnd:$rt, opnd:$offset);
   dag OutOperandList = (outs);
   string AsmString = !strconcat(instr_asm, "\t$rs, $rt, $offset");
   list<Register> Defs = [AT];
 }
 
 class CMP_CBR_EQNE_Z_DESC_BASE<string instr_asm, DAGOperand opnd,
-                               RegisterOperand GPROpnd> : BRANCH_DESC_BASE {
+                               RegisterOperand GPROpnd>
+    : BRANCH_DESC_BASE, MipsR6Arch<instr_asm> {
   dag InOperandList = (ins GPROpnd:$rs, opnd:$offset);
   dag OutOperandList = (outs);
   string AsmString = !strconcat(instr_asm, "\t$rs, $offset");
   list<Register> Defs = [AT];
 }
 
 class CMP_CBR_RT_Z_DESC_BASE<string instr_asm, DAGOperand opnd,
                              RegisterOperand GPROpnd>

 def BALC : R6MMR6Rel, BALC_ENC, BALC_DESC, ISA_MIPS32R6;
 def BC1EQZ : BC1EQZ_ENC, BC1EQZ_DESC, ISA_MIPS32R6, HARDFLOAT;
 def BC1NEZ : BC1NEZ_ENC, BC1NEZ_DESC, ISA_MIPS32R6, HARDFLOAT;
 def BC2EQZ : BC2EQZ_ENC, BC2EQZ_DESC, ISA_MIPS32R6;
 def BC2NEZ : BC2NEZ_ENC, BC2NEZ_DESC, ISA_MIPS32R6;
 def BC : R6MMR6Rel, BC_ENC, BC_DESC, ISA_MIPS32R6;
 def BEQC : BEQC_ENC, BEQC_DESC, ISA_MIPS32R6;
 def BEQZALC : R6MMR6Rel, BEQZALC_ENC, BEQZALC_DESC, ISA_MIPS32R6;
-def BEQZC : BEQZC_ENC, BEQZC_DESC, ISA_MIPS32R6;
+def BEQZC : R6MMR6Rel, BEQZC_ENC, BEQZC_DESC, ISA_MIPS32R6;
 def BGEC : BGEC_ENC, BGEC_DESC, ISA_MIPS32R6;
 def BGEUC : BGEUC_ENC, BGEUC_DESC, ISA_MIPS32R6;
 def BGEZALC : R6MMR6Rel, BGEZALC_ENC, BGEZALC_DESC, ISA_MIPS32R6;
 def BGEZC : BGEZC_ENC, BGEZC_DESC, ISA_MIPS32R6;
 def BGTZALC : R6MMR6Rel, BGTZALC_ENC, BGTZALC_DESC, ISA_MIPS32R6;
 def BGTZC : BGTZC_ENC, BGTZC_DESC, ISA_MIPS32R6;
 def BITSWAP : R6MMR6Rel, BITSWAP_ENC, BITSWAP_DESC, ISA_MIPS32R6;
 def BLEZALC : R6MMR6Rel, BLEZALC_ENC, BLEZALC_DESC, ISA_MIPS32R6;
 def BLEZC : BLEZC_ENC, BLEZC_DESC, ISA_MIPS32R6;
 def BLTC : BLTC_ENC, BLTC_DESC, ISA_MIPS32R6;
 def BLTUC : BLTUC_ENC, BLTUC_DESC, ISA_MIPS32R6;
 def BLTZALC : R6MMR6Rel, BLTZALC_ENC, BLTZALC_DESC, ISA_MIPS32R6;
 def BLTZC : BLTZC_ENC, BLTZC_DESC, ISA_MIPS32R6;
 def BNEC : BNEC_ENC, BNEC_DESC, ISA_MIPS32R6;
 def BNEZALC : R6MMR6Rel, BNEZALC_ENC, BNEZALC_DESC, ISA_MIPS32R6;
-def BNEZC : BNEZC_ENC, BNEZC_DESC, ISA_MIPS32R6;
+def BNEZC : R6MMR6Rel, BNEZC_ENC, BNEZC_DESC, ISA_MIPS32R6;
 def BNVC : BNVC_ENC, BNVC_DESC, ISA_MIPS32R6;
 def BOVC : BOVC_ENC, BOVC_DESC, ISA_MIPS32R6;
 def CACHE_R6 : R6MMR6Rel, CACHE_ENC, CACHE_DESC, ISA_MIPS32R6;
 let AdditionalPredicates = [NotInMicroMips] in {
   def CLASS_D : CLASS_D_ENC, CLASS_D_DESC, ISA_MIPS32R6, HARDFLOAT;
   def CLASS_S : CLASS_S_ENC, CLASS_S_DESC, ISA_MIPS32R6, HARDFLOAT;
 }
 def CLO_R6 : R6MMR6Rel, CLO_R6_ENC, CLO_R6_DESC, ISA_MIPS32R6;

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

 0xd0 0x64 0x04 0xd2 # CHECK: andi $3, $4, 1234
 0x10 0x62 0xff 0xe9 # CHECK: aui $3, $2, -23
 0x74 0x40 0x02 0x9a # CHECK: beqzalc $2, 1332
 0x7c 0x40 0x02 0x9a # CHECK: bnezalc $2, 1332
 0xc0 0x42 0x02 0x9a # CHECK: bgezalc $2, 1332
 0xe0 0x40 0x02 0x9a # CHECK: bgtzalc $2, 1332
 0xe0 0x42 0x02 0x9a # CHECK: bltzalc $2, 1332
 0xc0 0x40 0x02 0x9a # CHECK: blezalc $2, 1332
+0x80 0x60 0x00 0x20 # CHECK: beqzc $3, 64
+0xa0 0x60 0x00 0x20 # CHECK: bnezc $3, 64
 0xb4 0x37 0x96 0xb8 # CHECK: balc 7286128
 0x94 0x37 0x96 0xb8 # CHECK: bc 7286128
 0x00 0x44 0x0b 0x3c # CHECK: bitswap $4, $2
 0x00 0x00 0x00 0x07 # CHECK: break
 0x00 0x07 0x00 0x07 # CHECK: break 7
 0x00 0x07 0x01 0x47 # CHECK: break 7, 5
 0x20 0x25 0x60 0x08 # CHECK: cache 1, 8($5)
 0x01 0x65 0x4b 0x3c # CHECK: clo $11, $5

test/MC/Mips/micromips32r6/valid.s

# RUN: llvm-mc %s -triple=mips-unknown-linux -show-encoding -mcpu=mips32r6 -mattr=micromips | FileCheck %s
   align $4, $2, $3, 2      # CHECK: align $4, $2, $3, 2 # encoding: [0x00,0x43,0x24,0x1f]
   aui $3,$2,-23            # CHECK: aui $3, $2, -23     # encoding: [0x10,0x62,0xff,0xe9]
   beqzalc $2, 1332         # CHECK: beqzalc $2, 1332    # encoding: [0x74,0x40,0x02,0x9a]
   bnezalc $2, 1332         # CHECK: bnezalc $2, 1332    # encoding: [0x7c,0x40,0x02,0x9a]
   bgezalc $2, 1332         # CHECK: bgezalc $2, 1332    # encoding: [0xc0,0x42,0x02,0x9a]
   bgtzalc $2, 1332         # CHECK: bgtzalc $2, 1332    # encoding: [0xe0,0x40,0x02,0x9a]
   bltzalc $2, 1332         # CHECK: bltzalc $2, 1332    # encoding: [0xe0,0x42,0x02,0x9a]
   blezalc $2, 1332         # CHECK: blezalc $2, 1332    # encoding: [0xc0,0x40,0x02,0x9a]
+  beqzc   $3, 64           # CHECK: beqzc   $3, 64      # encoding: [0x80,0x60,0x00,0x20]
+  bnezc   $3, 64           # CHECK: bnezc   $3, 64      # encoding: [0xa0,0x60,0x00,0x20]
   balc 7286128             # CHECK: balc 7286128        # encoding: [0xb4,0x37,0x96,0xb8]
   b 132                    # CHECK: bc16 132            # encoding: [0xcc,0x42]
   bc 7286128               # CHECK: bc 7286128          # encoding: [0x94,0x37,0x96,0xb8]
   bc16 132                 # CHECK: bc16 132            # encoding: [0xcc,0x42]
   beqzc16 $6, 20           # CHECK: beqzc16 $6, 20      # encoding: [0x8f,0x0a]
   bnezc16 $6, 20           # CHECK: bnezc16 $6, 20      # encoding: [0xaf,0x0a]
   bitswap $4, $2           # CHECK: bitswap $4, $2      # encoding: [0x00,0x44,0x0b,0x3c]
   break                    # CHECK: break               # encoding: [0x00,0x00,0x00,0x07]