//===-- ARMBaseInfo.h - Top level definitions for ARM -------- --*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains small standalone helper functions and enum definitions for
// the ARM target useful for the compiler back-end and the MC libraries.
// As such, it deliberately does not include references to LLVM core
// code gen types, passes, etc..
//
//===----------------------------------------------------------------------===//

#ifndef ARMBASEINFO_H
#define ARMBASEINFO_H

#include "ARMMCTargetDesc.h"
#include "llvm/Support/ErrorHandling.h"

namespace llvm {

// Enums corresponding to ARM condition codes
namespace ARMCC {
  // The CondCodes constants map directly to the 4-bit encoding of the
  // condition field for predicated instructions.
  enum CondCodes { // Meaning (integer)          Meaning (floating-point)
    EQ,            // Equal                      Equal
    NE,            // Not equal                  Not equal, or unordered
    HS,            // Carry set                  >, ==, or unordered
    LO,            // Carry clear                Less than
    MI,            // Minus, negative            Less than
    PL,            // Plus, positive or zero     >, ==, or unordered
    VS,            // Overflow                   Unordered
    VC,            // No overflow                Not unordered
    HI,            // Unsigned higher            Greater than, or unordered
    LS,            // Unsigned lower or same     Less than or equal
    GE,            // Greater than or equal      Greater than or equal
    LT,            // Less than                  Less than, or unordered
    GT,            // Greater than               Greater than
    LE,            // Less than or equal         <, ==, or unordered
    AL             // Always (unconditional)     Always (unconditional)
  };

  inline static CondCodes getOppositeCondition(CondCodes CC) {
    switch (CC) {
    default: llvm_unreachable("Unknown condition code");
    case EQ: return NE;
    case NE: return EQ;
    case HS: return LO;
    case LO: return HS;
    case MI: return PL;
    case PL: return MI;
    case VS: return VC;
    case VC: return VS;
    case HI: return LS;
    case LS: return HI;
    case GE: return LT;
    case LT: return GE;
    case GT: return LE;
    case LE: return GT;
    }
  }
} // namespace ARMCC

inline static const char *ARMCondCodeToString(ARMCC::CondCodes CC) {
  switch (CC) {
  case ARMCC::EQ:  return "eq";
  case ARMCC::NE:  return "ne";
  case ARMCC::HS:  return "hs";
  case ARMCC::LO:  return "lo";
  case ARMCC::MI:  return "mi";
  case ARMCC::PL:  return "pl";
  case ARMCC::VS:  return "vs";
  case ARMCC::VC:  return "vc";
  case ARMCC::HI:  return "hi";
  case ARMCC::LS:  return "ls";
  case ARMCC::GE:  return "ge";
  case ARMCC::LT:  return "lt";
  case ARMCC::GT:  return "gt";
  case ARMCC::LE:  return "le";
  case ARMCC::AL:  return "al";
  }
  llvm_unreachable("Unknown condition code");
}

namespace ARM_PROC {
  enum IMod {
    IE = 2,
    ID = 3
  };

  enum IFlags {
    F = 1,
    I = 2,
    A = 4
  };

  inline static const char *IFlagsToString(unsigned val) {
    switch (val) {
    default: llvm_unreachable("Unknown iflags operand");
    case F: return "f";
    case I: return "i";
    case A: return "a";
    }
  }

  inline static const char *IModToString(unsigned val) {
    switch (val) {
    default: llvm_unreachable("Unknown imod operand");
    case IE: return "ie";
    case ID: return "id";
    }
  }
}

namespace ARM_MB {
  // The Memory Barrier Option constants map directly to the 4-bit encoding of
  // the option field for memory barrier operations.
  enum MemBOpt {
    RESERVED_0 = 0,
    RESERVED_1 = 1,
    OSHST = 2,
    OSH   = 3,
    RESERVED_4 = 4,
    RESERVED_5 = 5,
    NSHST = 6,
    NSH   = 7,
    RESERVED_8 = 8,
    RESERVED_9 = 9,
    ISHST = 10,
    ISH   = 11,
    RESERVED_12 = 12,
    RESERVED_13 = 13,
    ST    = 14,
    SY    = 15
  };

  inline static const char *MemBOptToString(unsigned val) {
    switch (val) {
    default: llvm_unreachable("Unknown memory operation");
    case SY:    return "sy";
    case ST:    return "st";
    case RESERVED_13: return "#0xd";
    case RESERVED_12: return "#0xc";
    case ISH:   return "ish";
    case ISHST: return "ishst";
    case RESERVED_9: return "#0x9";
    case RESERVED_8: return "#0x8";
    case NSH:   return "nsh";
    case NSHST: return "nshst";
    case RESERVED_5: return "#0x5";
    case RESERVED_4: return "#0x4";
    case OSH:   return "osh";
    case OSHST: return "oshst";
    case RESERVED_1: return "#0x1";
    case RESERVED_0: return "#0x0";
    }
  }
} // namespace ARM_MB

/// isARMLowRegister - Returns true if the register is a low register (r0-r7).
///
static inline bool isARMLowRegister(unsigned Reg) {
  using namespace ARM;
  switch (Reg) {
  case R0:  case R1:  case R2:  case R3:
  case R4:  case R5:  case R6:  case R7:
    return true;
  default:
    return false;
  }
}

/// ARMII - This namespace holds all of the target specific flags that
/// instruction info tracks.
///
namespace ARMII {

  /// ARM Index Modes
  enum IndexMode {
    IndexModeNone  = 0,
    IndexModePre   = 1,
    IndexModePost  = 2,
    IndexModeUpd   = 3
  };

  /// ARM Addressing Modes
  enum AddrMode {
    AddrModeNone    = 0,
    AddrMode1       = 1,
    AddrMode2       = 2,
    AddrMode3       = 3,
    AddrMode4       = 4,
    AddrMode5       = 5,
    AddrMode6       = 6,
    AddrModeT1_1    = 7,
    AddrModeT1_2    = 8,
    AddrModeT1_4    = 9,
    AddrModeT1_s    = 10, // i8 * 4 for pc and sp relative data
    AddrModeT2_i12  = 11,
    AddrModeT2_i8   = 12,
    AddrModeT2_so   = 13,
    AddrModeT2_pc   = 14, // +/- i12 for pc relative data
    AddrModeT2_i8s4 = 15, // i8 * 4
    AddrMode_i12    = 16
  };

  inline static const char *AddrModeToString(AddrMode addrmode) {
    switch (addrmode) {
    case AddrModeNone:    return "AddrModeNone";
    case AddrMode1:       return "AddrMode1";
    case AddrMode2:       return "AddrMode2";
    case AddrMode3:       return "AddrMode3";
    case AddrMode4:       return "AddrMode4";
    case AddrMode5:       return "AddrMode5";
    case AddrMode6:       return "AddrMode6";
    case AddrModeT1_1:    return "AddrModeT1_1";
    case AddrModeT1_2:    return "AddrModeT1_2";
    case AddrModeT1_4:    return "AddrModeT1_4";
    case AddrModeT1_s:    return "AddrModeT1_s";
    case AddrModeT2_i12:  return "AddrModeT2_i12";
    case AddrModeT2_i8:   return "AddrModeT2_i8";
    case AddrModeT2_so:   return "AddrModeT2_so";
    case AddrModeT2_pc:   return "AddrModeT2_pc";
    case AddrModeT2_i8s4: return "AddrModeT2_i8s4";
    case AddrMode_i12:    return "AddrMode_i12";
    }
  }

  /// Target Operand Flag enum.
  enum TOF {
    //===------------------------------------------------------------------===//
    // ARM Specific MachineOperand flags.

    MO_NO_FLAG,

    /// MO_LO16 - On a symbol operand, this represents a relocation containing
    /// lower 16 bit of the address. Used only via movw instruction.
    MO_LO16,

    /// MO_HI16 - On a symbol operand, this represents a relocation containing
    /// higher 16 bit of the address. Used only via movt instruction.
    MO_HI16,

    /// MO_LO16_NONLAZY - On a symbol operand "FOO", this represents a
    /// relocation containing lower 16 bit of the non-lazy-ptr indirect symbol,
    /// i.e. "FOO$non_lazy_ptr".
    /// Used only via movw instruction.
    MO_LO16_NONLAZY,

    /// MO_HI16_NONLAZY - On a symbol operand "FOO", this represents a
    /// relocation containing lower 16 bit of the non-lazy-ptr indirect symbol,
    /// i.e. "FOO$non_lazy_ptr". Used only via movt instruction.
    MO_HI16_NONLAZY,

    /// MO_LO16_NONLAZY_PIC - On a symbol operand "FOO", this represents a
    /// relocation containing lower 16 bit of the PC relative address of the
    /// non-lazy-ptr indirect symbol, i.e. "FOO$non_lazy_ptr - LABEL".
    /// Used only via movw instruction.
    MO_LO16_NONLAZY_PIC,

    /// MO_HI16_NONLAZY_PIC - On a symbol operand "FOO", this represents a
    /// relocation containing lower 16 bit of the PC relative address of the
    /// non-lazy-ptr indirect symbol, i.e. "FOO$non_lazy_ptr - LABEL".
    /// Used only via movt instruction.
    MO_HI16_NONLAZY_PIC,

    /// MO_PLT - On a symbol operand, this represents an ELF PLT reference on a
    /// call operand.
    MO_PLT
  };

  enum {
    //===------------------------------------------------------------------===//
    // Instruction Flags.

    //===------------------------------------------------------------------===//
    // This four-bit field describes the addressing mode used.
    AddrModeMask  = 0x1f, // The AddrMode enums are declared in ARMBaseInfo.h

    // IndexMode - Unindex, pre-indexed, or post-indexed are valid for load
    // and store ops only.  Generic "updating" flag is used for ld/st multiple.
    // The index mode enums are declared in ARMBaseInfo.h
    IndexModeShift = 5,
    IndexModeMask  = 3 << IndexModeShift,

    //===------------------------------------------------------------------===//
    // Instruction encoding formats.
    //
    FormShift     = 7,
    FormMask      = 0x3f << FormShift,

    // Pseudo instructions
    Pseudo        = 0  << FormShift,

    // Multiply instructions
    MulFrm        = 1  << FormShift,

    // Branch instructions
    BrFrm         = 2  << FormShift,
    BrMiscFrm     = 3  << FormShift,

    // Data Processing instructions
    DPFrm         = 4  << FormShift,
    DPSoRegFrm    = 5  << FormShift,

    // Load and Store
    LdFrm         = 6  << FormShift,
    StFrm         = 7  << FormShift,
    LdMiscFrm     = 8  << FormShift,
    StMiscFrm     = 9  << FormShift,
    LdStMulFrm    = 10 << FormShift,

    LdStExFrm     = 11 << FormShift,

    // Miscellaneous arithmetic instructions
    ArithMiscFrm  = 12 << FormShift,
    SatFrm        = 13 << FormShift,

    // Extend instructions
    ExtFrm        = 14 << FormShift,

    // VFP formats
    VFPUnaryFrm   = 15 << FormShift,
    VFPBinaryFrm  = 16 << FormShift,
    VFPConv1Frm   = 17 << FormShift,
    VFPConv2Frm   = 18 << FormShift,
    VFPConv3Frm   = 19 << FormShift,
    VFPConv4Frm   = 20 << FormShift,
    VFPConv5Frm   = 21 << FormShift,
    VFPLdStFrm    = 22 << FormShift,
    VFPLdStMulFrm = 23 << FormShift,
    VFPMiscFrm    = 24 << FormShift,

    // Thumb format
    ThumbFrm      = 25 << FormShift,

    // Miscelleaneous format
    MiscFrm       = 26 << FormShift,

    // NEON formats
    NGetLnFrm     = 27 << FormShift,
    NSetLnFrm     = 28 << FormShift,
    NDupFrm       = 29 << FormShift,
    NLdStFrm      = 30 << FormShift,
    N1RegModImmFrm= 31 << FormShift,
    N2RegFrm      = 32 << FormShift,
    NVCVTFrm      = 33 << FormShift,
    NVDupLnFrm    = 34 << FormShift,
    N2RegVShLFrm  = 35 << FormShift,
    N2RegVShRFrm  = 36 << FormShift,
    N3RegFrm      = 37 << FormShift,
    N3RegVShFrm   = 38 << FormShift,
    NVExtFrm      = 39 << FormShift,
    NVMulSLFrm    = 40 << FormShift,
    NVTBLFrm      = 41 << FormShift,

    //===------------------------------------------------------------------===//
    // Misc flags.

    // UnaryDP - Indicates this is a unary data processing instruction, i.e.
    // it doesn't have a Rn operand.
    UnaryDP       = 1 << 13,

    // Xform16Bit - Indicates this Thumb2 instruction may be transformed into
    // a 16-bit Thumb instruction if certain conditions are met.
    Xform16Bit    = 1 << 14,

    // ThumbArithFlagSetting - The instruction is a 16-bit flag setting Thumb
    // instruction. Used by the parser to determine whether to require the 'S'
    // suffix on the mnemonic (when not in an IT block) or preclude it (when
    // in an IT block).
    ThumbArithFlagSetting = 1 << 18,

    //===------------------------------------------------------------------===//
    // Code domain.
    DomainShift   = 15,
    DomainMask    = 7 << DomainShift,
    DomainGeneral = 0 << DomainShift,
    DomainVFP     = 1 << DomainShift,
    DomainNEON    = 2 << DomainShift,
    DomainNEONA8  = 4 << DomainShift,

    //===------------------------------------------------------------------===//
    // Field shifts - such shifts are used to set field while generating
    // machine instructions.
    //
    // FIXME: This list will need adjusting/fixing as the MC code emitter
    // takes shape and the ARMCodeEmitter.cpp bits go away.
    ShiftTypeShift = 4,

    M_BitShift     = 5,
    ShiftImmShift  = 5,
    ShiftShift     = 7,
    N_BitShift     = 7,
    ImmHiShift     = 8,
    SoRotImmShift  = 8,
    RegRsShift     = 8,
    ExtRotImmShift = 10,
    RegRdLoShift   = 12,
    RegRdShift     = 12,
    RegRdHiShift   = 16,
    RegRnShift     = 16,
    S_BitShift     = 20,
    W_BitShift     = 21,
    AM3_I_BitShift = 22,
    D_BitShift     = 22,
    U_BitShift     = 23,
    P_BitShift     = 24,
    I_BitShift     = 25,
    CondShift      = 28
  };

} // end namespace ARMII

} // end namespace llvm;

#endif