Support for microMIPS branch instructions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193992 91177308-0d34-0410-b5e6-96231b3b80d8

12 files changed, 159 insertions, 26 deletions

diff --git a/lib/Object/ELF.cpp b/lib/Object/ELF.cpp
index 2c62eb157e..7c80d41942 100644
--- a/lib/Object/ELF.cpp
+++ b/lib/Object/ELF.cpp
@@ -165,6 +165,7 @@ StringRef getELFRelocationTypeName(uint32_t Machine, uint32_t Type) {
       LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_MICROMIPS_HI16);
       LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_MICROMIPS_LO16);
       LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_MICROMIPS_GOT16);
+      LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_MICROMIPS_PC16_S1);
       LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_MICROMIPS_CALL16);
       LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_MICROMIPS_GOT_DISP);
       LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_MICROMIPS_GOT_PAGE);
diff --git a/lib/Target/Mips/Disassembler/MipsDisassembler.cpp b/lib/Target/Mips/Disassembler/MipsDisassembler.cpp
index f9bf1aff5e..b890d3a887 100644
--- a/lib/Target/Mips/Disassembler/MipsDisassembler.cpp
+++ b/lib/Target/Mips/Disassembler/MipsDisassembler.cpp
@@ -205,6 +205,13 @@ static DecodeStatus DecodeJumpTarget(MCInst &Inst,
                                      uint64_t Address,
                                      const void *Decoder);
 
+// DecodeBranchTargetMM - Decode microMIPS branch offset, which is
+// shifted left by 1 bit.
+static DecodeStatus DecodeBranchTargetMM(MCInst &Inst,
+                                         unsigned Offset,
+                                         uint64_t Address,
+                                         const void *Decoder);
+
 // DecodeJumpTargetMM - Decode microMIPS jump target, which is
 // shifted left by 1 bit.
 static DecodeStatus DecodeJumpTargetMM(MCInst &Inst,
@@ -751,6 +758,16 @@ static DecodeStatus DecodeJumpTarget(MCInst &Inst,
   return MCDisassembler::Success;
 }
 
+static DecodeStatus DecodeBranchTargetMM(MCInst &Inst,
+                                         unsigned Offset,
+                                         uint64_t Address,
+                                         const void *Decoder) {
+  unsigned BranchOffset = Offset & 0xffff;
+  BranchOffset = SignExtend32<18>(BranchOffset << 1);
+  Inst.addOperand(MCOperand::CreateImm(BranchOffset));
+  return MCDisassembler::Success;
+}
+
 static DecodeStatus DecodeJumpTargetMM(MCInst &Inst,
                                        unsigned Insn,
                                        uint64_t Address,
diff --git a/lib/Target/Mips/MCTargetDesc/MipsAsmBackend.cpp b/lib/Target/Mips/MCTargetDesc/MipsAsmBackend.cpp
index b47bff66f1..3e70b23dcc 100644
--- a/lib/Target/Mips/MCTargetDesc/MipsAsmBackend.cpp
+++ b/lib/Target/Mips/MCTargetDesc/MipsAsmBackend.cpp
@@ -84,6 +84,10 @@ static unsigned adjustFixupValue(unsigned Kind, uint64_t Value) {
   case Mips::fixup_MICROMIPS_26_S1:
     Value >>= 1;
     break;
+  case Mips::fixup_MICROMIPS_PC16_S1:
+    Value -= 4;
+    Value >>= 1;
+    break;
   }
 
   return Value;
@@ -201,6 +205,7 @@ public:
       { "fixup_MICROMIPS_HI16",    0,     16,   0 },
       { "fixup_MICROMIPS_LO16",    0,     16,   0 },
       { "fixup_MICROMIPS_GOT16",   0,     16,   0 },
+      { "fixup_MICROMIPS_PC16_S1", 0,     16,   MCFixupKindInfo::FKF_IsPCRel },
       { "fixup_MICROMIPS_CALL16",  0,     16,   0 },
       { "fixup_MICROMIPS_GOT_DISP",        0,     16,   0 },
       { "fixup_MICROMIPS_GOT_PAGE",        0,     16,   0 },
diff --git a/lib/Target/Mips/MCTargetDesc/MipsELFObjectWriter.cpp b/lib/Target/Mips/MCTargetDesc/MipsELFObjectWriter.cpp
index 60c9f33341..83c7d4bcc3 100644
--- a/lib/Target/Mips/MCTargetDesc/MipsELFObjectWriter.cpp
+++ b/lib/Target/Mips/MCTargetDesc/MipsELFObjectWriter.cpp
@@ -195,6 +195,9 @@ unsigned MipsELFObjectWriter::GetRelocType(const MCValue &Target,
   case Mips::fixup_MICROMIPS_GOT16:
     Type = ELF::R_MICROMIPS_GOT16;
     break;
+  case Mips::fixup_MICROMIPS_PC16_S1:
+    Type = ELF::R_MICROMIPS_PC16_S1;
+    break;
   case Mips::fixup_MICROMIPS_CALL16:
     Type = ELF::R_MICROMIPS_CALL16;
     break;
diff --git a/lib/Target/Mips/MCTargetDesc/MipsFixupKinds.h b/lib/Target/Mips/MCTargetDesc/MipsFixupKinds.h
index ab7eeada44..6ed44b74cc 100644
--- a/lib/Target/Mips/MCTargetDesc/MipsFixupKinds.h
+++ b/lib/Target/Mips/MCTargetDesc/MipsFixupKinds.h
@@ -140,6 +140,9 @@ namespace Mips {
     // resulting in - R_MICROMIPS_GOT16
     fixup_MICROMIPS_GOT16,
 
+    // resulting in - R_MICROMIPS_PC16_S1
+    fixup_MICROMIPS_PC16_S1,
+
     // resulting in - R_MICROMIPS_CALL16
     fixup_MICROMIPS_CALL16,
 
diff --git a/lib/Target/Mips/MCTargetDesc/MipsMCCodeEmitter.cpp b/lib/Target/Mips/MCTargetDesc/MipsMCCodeEmitter.cpp
index b965d134ed..79818ec0bf 100644
--- a/lib/Target/Mips/MCTargetDesc/MipsMCCodeEmitter.cpp
+++ b/lib/Target/Mips/MCTargetDesc/MipsMCCodeEmitter.cpp
@@ -96,6 +96,12 @@ public:
   unsigned getBranchTargetOpValue(const MCInst &MI, unsigned OpNo,
                                   SmallVectorImpl<MCFixup> &Fixups) const;
 
+  // getBranchTargetOpValue - Return binary encoding of the microMIPS branch
+  // target operand. If the machine operand requires relocation,
+  // record the relocation and return zero.
+  unsigned getBranchTargetOpValueMM(const MCInst &MI, unsigned OpNo,
+                                    SmallVectorImpl<MCFixup> &Fixups) const;
+
    // getMachineOpValue - Return binary encoding of operand. If the machin
    // operand requires relocation, record the relocation and return zero.
   unsigned getMachineOpValue(const MCInst &MI,const MCOperand &MO,
@@ -276,6 +282,28 @@ getBranchTargetOpValue(const MCInst &MI, unsigned OpNo,
   return 0;
 }
 
+/// getBranchTargetOpValue - Return binary encoding of the microMIPS branch
+/// target operand. If the machine operand requires relocation,
+/// record the relocation and return zero.
+unsigned MipsMCCodeEmitter::
+getBranchTargetOpValueMM(const MCInst &MI, unsigned OpNo,
+                         SmallVectorImpl<MCFixup> &Fixups) 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() &&
+         "getBranchTargetOpValueMM expects only expressions or immediates");
+
+  const MCExpr *Expr = MO.getExpr();
+  Fixups.push_back(MCFixup::Create(0, Expr,
+                   MCFixupKind(Mips::
+                               fixup_MICROMIPS_PC16_S1)));
+  return 0;
+}
+
 /// getJumpTargetOpValue - Return binary encoding of the jump
 /// target operand. If the machine operand requires relocation,
 /// record the relocation and return zero.
diff --git a/lib/Target/Mips/MicroMipsInstrFormats.td b/lib/Target/Mips/MicroMipsInstrFormats.td
index 61a3788b90..4981608bf2 100644
--- a/lib/Target/Mips/MicroMipsInstrFormats.td
+++ b/lib/Target/Mips/MicroMipsInstrFormats.td
@@ -238,3 +238,40 @@ class JALR_FM_MM<bits<10> funct> : MMArch {
   let Inst{15-6}  = funct;
   let Inst{5-0}   = 0x3c;
 }
+
+class BEQ_FM_MM<bits<6> op> : MMArch {
+  bits<5>  rs;
+  bits<5>  rt;
+  bits<16> offset;
+
+  bits<32> Inst;
+
+  let Inst{31-26} = op;
+  let Inst{25-21} = rt;
+  let Inst{20-16} = rs;
+  let Inst{15-0}  = offset;
+}
+
+class BGEZ_FM_MM<bits<5> funct> : MMArch {
+  bits<5>  rs;
+  bits<16> offset;
+
+  bits<32> Inst;
+
+  let Inst{31-26} = 0x10;
+  let Inst{25-21} = funct;
+  let Inst{20-16} = rs;
+  let Inst{15-0}  = offset;
+}
+
+class BGEZAL_FM_MM<bits<5> funct> : MMArch {
+  bits<5>  rs;
+  bits<16> offset;
+
+  bits<32> Inst;
+
+  let Inst{31-26} = 0x10;
+  let Inst{25-21} = funct;
+  let Inst{20-16} = rs;
+  let Inst{15-0}  = offset;
+}
diff --git a/lib/Target/Mips/MicroMipsInstrInfo.td b/lib/Target/Mips/MicroMipsInstrInfo.td
index 41273bc4de..297b8385a7 100644
--- a/lib/Target/Mips/MicroMipsInstrInfo.td
+++ b/lib/Target/Mips/MicroMipsInstrInfo.td
@@ -20,6 +20,12 @@ def calltarget_mm : Operand<iPTR> {
   let EncoderMethod = "getJumpTargetOpValueMM";
 }
 
+def brtarget_mm : Operand<OtherVT> {
+  let EncoderMethod = "getBranchTargetOpValueMM";
+  let OperandType   = "OPERAND_PCREL";
+  let DecoderMethod = "DecodeBranchTargetMM";
+}
+
 let canFoldAsLoad = 1 in
 class LoadLeftRightMM<string opstr, SDNode OpNode, RegisterOperand RO,
                       Operand MemOpnd> :
@@ -177,4 +183,22 @@ let DecoderNamespace = "MicroMips", Predicates = [InMicroMips] in {
   def TAILCALL_R_MM : MMRel, JumpFR<"tcallr", GPR32Opnd, MipsTailCall>,
                       JR_FM_MM<0x3c>, IsTailCall;
   def RET_MM : MMRel, RetBase<"ret", GPR32Opnd>, JR_FM_MM<0x3c>;
+
+  /// Branch Instructions
+  def BEQ_MM  : MMRel, CBranch<"beq", brtarget_mm, seteq, GPR32Opnd>,
+                BEQ_FM_MM<0x25>;
+  def BNE_MM  : MMRel, CBranch<"bne", brtarget_mm, setne, GPR32Opnd>,
+                BEQ_FM_MM<0x2d>;
+  def BGEZ_MM : MMRel, CBranchZero<"bgez", brtarget_mm, setge, GPR32Opnd>,
+                BGEZ_FM_MM<0x2>;
+  def BGTZ_MM : MMRel, CBranchZero<"bgtz", brtarget_mm, setgt, GPR32Opnd>,
+                BGEZ_FM_MM<0x6>;
+  def BLEZ_MM : MMRel, CBranchZero<"blez", brtarget_mm, setle, GPR32Opnd>,
+                BGEZ_FM_MM<0x4>;
+  def BLTZ_MM : MMRel, CBranchZero<"bltz", brtarget_mm, setlt, GPR32Opnd>,
+                BGEZ_FM_MM<0x0>;
+  def BGEZAL_MM : MMRel, BGEZAL_FT<"bgezal", brtarget_mm, GPR32Opnd>,
+                  BGEZAL_FM_MM<0x03>;
+  def BLTZAL_MM : MMRel, BGEZAL_FT<"bltzal", brtarget_mm, GPR32Opnd>,
+                  BGEZAL_FM_MM<0x01>;
 }
diff --git a/lib/Target/Mips/Mips64InstrInfo.td b/lib/Target/Mips/Mips64InstrInfo.td
index 3b74ced716..15ef654555 100644
--- a/lib/Target/Mips/Mips64InstrInfo.td
+++ b/lib/Target/Mips/Mips64InstrInfo.td
@@ -151,12 +151,12 @@ def SCD : SCBase<"scd", GPR64Opnd>, LW_FM<0x3c>;
 /// Jump and Branch Instructions
 let isCodeGenOnly = 1 in {
 def JR64   : IndirectBranch<"jr", GPR64Opnd>, MTLO_FM<8>;
-def BEQ64  : CBranch<"beq", seteq, GPR64Opnd>, BEQ_FM<4>;
-def BNE64  : CBranch<"bne", setne, GPR64Opnd>, BEQ_FM<5>;
-def BGEZ64 : CBranchZero<"bgez", setge, GPR64Opnd>, BGEZ_FM<1, 1>;
-def BGTZ64 : CBranchZero<"bgtz", setgt, GPR64Opnd>, BGEZ_FM<7, 0>;
-def BLEZ64 : CBranchZero<"blez", setle, GPR64Opnd>, BGEZ_FM<6, 0>;
-def BLTZ64 : CBranchZero<"bltz", setlt, GPR64Opnd>, BGEZ_FM<1, 0>;
+def BEQ64  : CBranch<"beq", brtarget, seteq, GPR64Opnd>, BEQ_FM<4>;
+def BNE64  : CBranch<"bne", brtarget, setne, GPR64Opnd>, BEQ_FM<5>;
+def BGEZ64 : CBranchZero<"bgez", brtarget, setge, GPR64Opnd>, BGEZ_FM<1, 1>;
+def BGTZ64 : CBranchZero<"bgtz", brtarget, setgt, GPR64Opnd>, BGEZ_FM<7, 0>;
+def BLEZ64 : CBranchZero<"blez", brtarget, setle, GPR64Opnd>, BGEZ_FM<6, 0>;
+def BLTZ64 : CBranchZero<"bltz", brtarget, setlt, GPR64Opnd>, BGEZ_FM<1, 0>;
 def JALR64 : JumpLinkReg<"jalr", GPR64Opnd>, JALR_FM;
 def JALR64Pseudo : JumpLinkRegPseudo<GPR64Opnd, JALR, RA, GPR32Opnd>;
 def TAILCALL64_R : JumpFR<"tcallr", GPR64Opnd, MipsTailCall>,
diff --git a/lib/Target/Mips/MipsCodeEmitter.cpp b/lib/Target/Mips/MipsCodeEmitter.cpp
index 3c737e67de..f4e1e1848e 100644
--- a/lib/Target/Mips/MipsCodeEmitter.cpp
+++ b/lib/Target/Mips/MipsCodeEmitter.cpp
@@ -106,6 +106,8 @@ private:
 
   unsigned getJumpTargetOpValue(const MachineInstr &MI, unsigned OpNo) const;
   unsigned getJumpTargetOpValueMM(const MachineInstr &MI, unsigned OpNo) const;
+  unsigned getBranchTargetOpValueMM(const MachineInstr &MI,
+                                    unsigned OpNo) const;
 
   unsigned getBranchTargetOpValue(const MachineInstr &MI, unsigned OpNo) const;
   unsigned getMemEncoding(const MachineInstr &MI, unsigned OpNo) const;
@@ -194,6 +196,12 @@ unsigned MipsCodeEmitter::getJumpTargetOpValueMM(const MachineInstr &MI,
   return 0;
 }
 
+unsigned MipsCodeEmitter::getBranchTargetOpValueMM(const MachineInstr &MI,
+                                                   unsigned OpNo) const {
+  llvm_unreachable("Unimplemented function.");
+  return 0;
+}
+
 unsigned MipsCodeEmitter::getBranchTargetOpValue(const MachineInstr &MI,
                                                  unsigned OpNo) const {
   MachineOperand MO = MI.getOperand(OpNo);
diff --git a/lib/Target/Mips/MipsInstrFormats.td b/lib/Target/Mips/MipsInstrFormats.td
index c46706b151..8f67b2e5ed 100644
--- a/lib/Target/Mips/MipsInstrFormats.td
+++ b/lib/Target/Mips/MipsInstrFormats.td
@@ -272,7 +272,7 @@ class SRLV_FM<bits<6> funct, bit rotate> : StdArch {
   let Inst{5-0}   = funct;
 }
 
-class BEQ_FM<bits<6> op> {
+class BEQ_FM<bits<6> op> : StdArch {
   bits<5>  rs;
   bits<5>  rt;
   bits<16> offset;
@@ -285,7 +285,7 @@ class BEQ_FM<bits<6> op> {
   let Inst{15-0}  = offset;
 }
 
-class BGEZ_FM<bits<6> op, bits<5> funct> {
+class BGEZ_FM<bits<6> op, bits<5> funct> : StdArch {
   bits<5>  rs;
   bits<16> offset;
 
@@ -389,7 +389,7 @@ class JALR_FM : StdArch {
   let Inst{5-0}   = 9;
 }
 
-class BGEZAL_FM<bits<5> funct> {
+class BGEZAL_FM<bits<5> funct> : StdArch {
   bits<5>  rs;
   bits<16> offset;
 
diff --git a/lib/Target/Mips/MipsInstrInfo.td b/lib/Target/Mips/MipsInstrInfo.td
index f5a519d71c..400bee6d7e 100644
--- a/lib/Target/Mips/MipsInstrInfo.td
+++ b/lib/Target/Mips/MipsInstrInfo.td
@@ -504,21 +504,24 @@ class StoreLeftRight<string opstr, SDNode OpNode, RegisterOperand RO,
 }
 
 // Conditional Branch
-class CBranch<string opstr, PatFrag cond_op, RegisterOperand RO> :
-  InstSE<(outs), (ins RO:$rs, RO:$rt, brtarget:$offset),
+class CBranch<string opstr, DAGOperand opnd, PatFrag cond_op,
+              RegisterOperand RO> :
+  InstSE<(outs), (ins RO:$rs, RO:$rt, opnd:$offset),
          !strconcat(opstr, "\t$rs, $rt, $offset"),
          [(brcond (i32 (cond_op RO:$rs, RO:$rt)), bb:$offset)], IIBranch,
-         FrmI> {
+         FrmI, opstr> {
   let isBranch = 1;
   let isTerminator = 1;
   let hasDelaySlot = 1;
   let Defs = [AT];
 }
 
-class CBranchZero<string opstr, PatFrag cond_op, RegisterOperand RO> :
-  InstSE<(outs), (ins RO:$rs, brtarget:$offset),
+class CBranchZero<string opstr, DAGOperand opnd, PatFrag cond_op,
+                  RegisterOperand RO> :
+  InstSE<(outs), (ins RO:$rs, opnd:$offset),
          !strconcat(opstr, "\t$rs, $offset"),
-         [(brcond (i32 (cond_op RO:$rs, 0)), bb:$offset)], IIBranch, FrmI> {
+         [(brcond (i32 (cond_op RO:$rs, 0)), bb:$offset)], IIBranch,
+         FrmI, opstr> {
   let isBranch = 1;
   let isTerminator = 1;
   let hasDelaySlot = 1;
@@ -602,9 +605,9 @@ let isCall=1, hasDelaySlot=1, Defs = [RA] in {
     InstSE<(outs RO:$rd), (ins RO:$rs), !strconcat(opstr, "\t$rd, $rs"),
            [], IIBranch, FrmR, opstr>;
 
-  class BGEZAL_FT<string opstr, RegisterOperand RO> :
-    InstSE<(outs), (ins RO:$rs, brtarget:$offset),
-           !strconcat(opstr, "\t$rs, $offset"), [], IIBranch, FrmI>;
+  class BGEZAL_FT<string opstr, DAGOperand opnd, RegisterOperand RO> :
+    InstSE<(outs), (ins RO:$rs, opnd:$offset),
+           !strconcat(opstr, "\t$rs, $offset"), [], IIBranch, FrmI, opstr>;
 
 }
 
@@ -994,19 +997,23 @@ def SC : SCBase<"sc", GPR32Opnd>, LW_FM<0x38>;
 def J       : MMRel, JumpFJ<jmptarget, "j", br, bb, "j">, FJ<2>,
               Requires<[RelocStatic, HasStdEnc]>, IsBranch;
 def JR      : MMRel, IndirectBranch<"jr", GPR32Opnd>, MTLO_FM<8>;
-def BEQ     : CBranch<"beq", seteq, GPR32Opnd>, BEQ_FM<4>;
-def BNE     : CBranch<"bne", setne, GPR32Opnd>, BEQ_FM<5>;
-def BGEZ    : CBranchZero<"bgez", setge, GPR32Opnd>, BGEZ_FM<1, 1>;
-def BGTZ    : CBranchZero<"bgtz", setgt, GPR32Opnd>, BGEZ_FM<7, 0>;
-def BLEZ    : CBranchZero<"blez", setle, GPR32Opnd>, BGEZ_FM<6, 0>;
-def BLTZ    : CBranchZero<"bltz", setlt, GPR32Opnd>, BGEZ_FM<1, 0>;
+def BEQ     : MMRel, CBranch<"beq", brtarget, seteq, GPR32Opnd>, BEQ_FM<4>;
+def BNE     : MMRel, CBranch<"bne", brtarget, setne, GPR32Opnd>, BEQ_FM<5>;
+def BGEZ    : MMRel, CBranchZero<"bgez", brtarget, setge, GPR32Opnd>,
+              BGEZ_FM<1, 1>;
+def BGTZ    : MMRel, CBranchZero<"bgtz", brtarget, setgt, GPR32Opnd>,
+              BGEZ_FM<7, 0>;
+def BLEZ    : MMRel, CBranchZero<"blez", brtarget, setle, GPR32Opnd>,
+              BGEZ_FM<6, 0>;
+def BLTZ    : MMRel, CBranchZero<"bltz", brtarget, setlt, GPR32Opnd>,
+              BGEZ_FM<1, 0>;
 def B       : UncondBranch<BEQ>;
 
 def JAL  : MMRel, JumpLink<"jal", calltarget>, FJ<3>;
 def JALR : MMRel, JumpLinkReg<"jalr", GPR32Opnd>, JALR_FM;
 def JALRPseudo : JumpLinkRegPseudo<GPR32Opnd, JALR, RA>;
-def BGEZAL : BGEZAL_FT<"bgezal", GPR32Opnd>, BGEZAL_FM<0x11>;
-def BLTZAL : BGEZAL_FT<"bltzal", GPR32Opnd>, BGEZAL_FM<0x10>;
+def BGEZAL : MMRel, BGEZAL_FT<"bgezal", brtarget, GPR32Opnd>, BGEZAL_FM<0x11>;
+def BLTZAL : MMRel, BGEZAL_FT<"bltzal", brtarget, GPR32Opnd>, BGEZAL_FM<0x10>;
 def BAL_BR : BAL_BR_Pseudo<BGEZAL>;
 def TAILCALL : MMRel, JumpFJ<calltarget, "j", MipsTailCall, imm, "tcall">,
                FJ<2>, IsTailCall;