/* This file is part of the dynarmic project.
 * Copyright (c) 2016 MerryMage
 * This software may be used and distributed according to the terms of the GNU
 * General Public License version 2 or any later version.
 */

#include "translate_arm.h"

namespace Dynarmic {
namespace Arm {

static ExtReg ToExtReg(bool sz, size_t base, bool bit) {
    if (sz) {
        return static_cast<ExtReg>(static_cast<size_t>(ExtReg::D0) + base + (bit ? 16 : 0));
    } else {
        return static_cast<ExtReg>(static_cast<size_t>(ExtReg::S0) + (base << 1) + (bit ? 1 : 0));
    }
}

template <typename FnT>
bool ArmTranslatorVisitor::EmitVfpVectorOperation(bool sz, ExtReg d, ExtReg n, ExtReg m, const FnT& fn) {
    // VFP register banks are 8 single-precision registers in size.
    const size_t register_bank_size = sz ? 4 : 8;

    if (!ir.current_location.FPSCR().Stride()) {
        return UnpredictableInstruction();
    }

    size_t vector_length = ir.current_location.FPSCR().Len();
    size_t vector_stride = *ir.current_location.FPSCR().Stride();

    // Unpredictable case
    if (vector_stride * vector_length > register_bank_size) {
        return UnpredictableInstruction();
    }

    // Scalar case
    if (vector_length == 1) {
        if (vector_stride != 1)
            return UnpredictableInstruction();

        fn(d, n, m);
        return true;
    }

    // The VFP register file is divided into banks each containing:
    // * eight single-precision registers, or
    // * four double-precision reigsters.
    // VFP vector instructions access these registers in a circular manner.
    const auto bank_increment = [register_bank_size](ExtReg reg, size_t stride) -> ExtReg {
        size_t reg_number = static_cast<size_t>(reg);
        size_t bank_index = reg_number % register_bank_size;
        size_t bank_start = reg_number - bank_index;
        size_t next_reg_number = bank_start + ((bank_index + stride) % register_bank_size);
        return static_cast<ExtReg>(next_reg_number);
    };

    // The first and fifth banks in the register file are scalar banks.
    // All the other banks are vector banks.
    const auto belongs_to_scalar_bank = [](ExtReg reg) -> bool {
        return (reg >= ExtReg::D0 && reg <= ExtReg::D3)
            || (reg >= ExtReg::D16 && reg <= ExtReg::D19)
            || (reg >= ExtReg::S0 && reg <= ExtReg::S7);
    };

    const bool d_is_scalar = belongs_to_scalar_bank(d);
    const bool m_is_scalar = belongs_to_scalar_bank(m);

    if (d_is_scalar) {
        // If destination register is in a scalar bank, the operands and results are all scalars.
        vector_length = 1;
    }

    for (size_t i = 0; i < vector_length; i++) {
        fn(d, n, m);

        d = bank_increment(d, vector_stride);
        n = bank_increment(n, vector_stride);
        if (!m_is_scalar)
            m = bank_increment(m, vector_stride);
    }

    return true;
}

template <typename FnT>
bool ArmTranslatorVisitor::EmitVfpVectorOperation(bool sz, ExtReg d, ExtReg m, const FnT& fn) {
    return EmitVfpVectorOperation(sz, d, ExtReg::S0, m, [fn](ExtReg d, ExtReg, ExtReg m){
        fn(d, m);
    });
}

bool ArmTranslatorVisitor::vfp2_VADD(Cond cond, bool D, size_t Vn, size_t Vd, bool sz, bool N, bool M, size_t Vm) {
    ExtReg d = ToExtReg(sz, Vd, D);
    ExtReg n = ToExtReg(sz, Vn, N);
    ExtReg m = ToExtReg(sz, Vm, M);
    // VADD.{F32,F64} <{S,D}d>, <{S,D}n>, <{S,D}m>
    if (ConditionPassed(cond)) {
        return EmitVfpVectorOperation(sz, d, n, m, [sz, this](ExtReg d, ExtReg n, ExtReg m) {
            auto reg_n = ir.GetExtendedRegister(n);
            auto reg_m = ir.GetExtendedRegister(m);
            auto result = sz
                          ? ir.FPAdd64(reg_n, reg_m, true)
                          : ir.FPAdd32(reg_n, reg_m, true);
            ir.SetExtendedRegister(d, result);
        });
    }
    return true;
}

bool ArmTranslatorVisitor::vfp2_VSUB(Cond cond, bool D, size_t Vn, size_t Vd, bool sz, bool N, bool M, size_t Vm) {
    ExtReg d = ToExtReg(sz, Vd, D);
    ExtReg n = ToExtReg(sz, Vn, N);
    ExtReg m = ToExtReg(sz, Vm, M);
    // VSUB.{F32,F64} <{S,D}d>, <{S,D}n>, <{S,D}m>
    if (ConditionPassed(cond)) {
        return EmitVfpVectorOperation(sz, d, n, m, [sz, this](ExtReg d, ExtReg n, ExtReg m) {
            auto reg_n = ir.GetExtendedRegister(n);
            auto reg_m = ir.GetExtendedRegister(m);
            auto result = sz
                          ? ir.FPSub64(reg_n, reg_m, true)
                          : ir.FPSub32(reg_n, reg_m, true);
            ir.SetExtendedRegister(d, result);
        });
    }
    return true;
}

bool ArmTranslatorVisitor::vfp2_VMUL(Cond cond, bool D, size_t Vn, size_t Vd, bool sz, bool N, bool M, size_t Vm) {
    ExtReg d = ToExtReg(sz, Vd, D);
    ExtReg n = ToExtReg(sz, Vn, N);
    ExtReg m = ToExtReg(sz, Vm, M);
    // VMUL.{F32,F64} <{S,D}d>, <{S,D}n>, <{S,D}m>
    if (ConditionPassed(cond)) {
        return EmitVfpVectorOperation(sz, d, n, m, [sz, this](ExtReg d, ExtReg n, ExtReg m) {
            auto reg_n = ir.GetExtendedRegister(n);
            auto reg_m = ir.GetExtendedRegister(m);
            auto result = sz
                          ? ir.FPMul64(reg_n, reg_m, true)
                          : ir.FPMul32(reg_n, reg_m, true);
            ir.SetExtendedRegister(d, result);
        });
    }
    return true;
}

bool ArmTranslatorVisitor::vfp2_VMLA(Cond cond, bool D, size_t Vn, size_t Vd, bool sz, bool N, bool M, size_t Vm) {
    ExtReg d = ToExtReg(sz, Vd, D);
    ExtReg n = ToExtReg(sz, Vn, N);
    ExtReg m = ToExtReg(sz, Vm, M);
    // VMLA.{F32,F64} <{S,D}d>, <{S,D}n>, <{S,D}m>
    if (ConditionPassed(cond)) {
        return EmitVfpVectorOperation(sz, d, n, m, [sz, this](ExtReg d, ExtReg n, ExtReg m) {
            auto reg_n = ir.GetExtendedRegister(n);
            auto reg_m = ir.GetExtendedRegister(m);
            auto reg_d = ir.GetExtendedRegister(d);
            auto result = sz
                          ? ir.FPAdd64(reg_d, ir.FPMul64(reg_n, reg_m, true), true)
                          : ir.FPAdd32(reg_d, ir.FPMul32(reg_n, reg_m, true), true);
            ir.SetExtendedRegister(d, result);
        });
    }
    return true;
}

bool ArmTranslatorVisitor::vfp2_VMLS(Cond cond, bool D, size_t Vn, size_t Vd, bool sz, bool N, bool M, size_t Vm) {
    ExtReg d = ToExtReg(sz, Vd, D);
    ExtReg n = ToExtReg(sz, Vn, N);
    ExtReg m = ToExtReg(sz, Vm, M);
    // VMLS.{F32,F64} <{S,D}d>, <{S,D}n>, <{S,D}m>
    if (ConditionPassed(cond)) {
        return EmitVfpVectorOperation(sz, d, n, m, [sz, this](ExtReg d, ExtReg n, ExtReg m) {
            auto reg_n = ir.GetExtendedRegister(n);
            auto reg_m = ir.GetExtendedRegister(m);
            auto reg_d = ir.GetExtendedRegister(d);
            auto result = sz
                          ? ir.FPAdd64(reg_d, ir.FPNeg64(ir.FPMul64(reg_n, reg_m, true)), true)
                          : ir.FPAdd32(reg_d, ir.FPNeg32(ir.FPMul32(reg_n, reg_m, true)), true);
            ir.SetExtendedRegister(d, result);
        });
    }
    return true;
}

bool ArmTranslatorVisitor::vfp2_VNMUL(Cond cond, bool D, size_t Vn, size_t Vd, bool sz, bool N, bool M, size_t Vm) {
    ExtReg d = ToExtReg(sz, Vd, D);
    ExtReg n = ToExtReg(sz, Vn, N);
    ExtReg m = ToExtReg(sz, Vm, M);
    // VNMUL.{F32,F64} <{S,D}d>, <{S,D}n>, <{S,D}m>
    if (ConditionPassed(cond)) {
        return EmitVfpVectorOperation(sz, d, n, m, [sz, this](ExtReg d, ExtReg n, ExtReg m) {
            auto reg_n = ir.GetExtendedRegister(n);
            auto reg_m = ir.GetExtendedRegister(m);
            auto result = sz
                          ? ir.FPNeg64(ir.FPMul64(reg_n, reg_m, true))
                          : ir.FPNeg32(ir.FPMul32(reg_n, reg_m, true));
            ir.SetExtendedRegister(d, result);
        });
    }
    return true;
}

bool ArmTranslatorVisitor::vfp2_VNMLA(Cond cond, bool D, size_t Vn, size_t Vd, bool sz, bool N, bool M, size_t Vm) {
    ExtReg d = ToExtReg(sz, Vd, D);
    ExtReg n = ToExtReg(sz, Vn, N);
    ExtReg m = ToExtReg(sz, Vm, M);
    // VNMLA.{F32,F64} <{S,D}d>, <{S,D}n>, <{S,D}m>
    if (ConditionPassed(cond)) {
        return EmitVfpVectorOperation(sz, d, n, m, [sz, this](ExtReg d, ExtReg n, ExtReg m) {
            auto reg_n = ir.GetExtendedRegister(n);
            auto reg_m = ir.GetExtendedRegister(m);
            auto reg_d = ir.GetExtendedRegister(d);
            auto result = sz
                          ? ir.FPAdd64(ir.FPNeg64(reg_d), ir.FPNeg64(ir.FPMul64(reg_n, reg_m, true)), true)
                          : ir.FPAdd32(ir.FPNeg32(reg_d), ir.FPNeg32(ir.FPMul32(reg_n, reg_m, true)), true);
            ir.SetExtendedRegister(d, result);
        });
    }
    return true;
}

bool ArmTranslatorVisitor::vfp2_VNMLS(Cond cond, bool D, size_t Vn, size_t Vd, bool sz, bool N, bool M, size_t Vm) {
    ExtReg d = ToExtReg(sz, Vd, D);
    ExtReg n = ToExtReg(sz, Vn, N);
    ExtReg m = ToExtReg(sz, Vm, M);
    // VNMLS.{F32,F64} <{S,D}d>, <{S,D}n>, <{S,D}m>
    if (ConditionPassed(cond)) {
        return EmitVfpVectorOperation(sz, d, n, m, [sz, this](ExtReg d, ExtReg n, ExtReg m) {
            auto reg_n = ir.GetExtendedRegister(n);
            auto reg_m = ir.GetExtendedRegister(m);
            auto reg_d = ir.GetExtendedRegister(d);
            auto result = sz
                          ? ir.FPAdd64(ir.FPNeg64(reg_d), ir.FPMul64(reg_n, reg_m, true), true)
                          : ir.FPAdd32(ir.FPNeg32(reg_d), ir.FPMul32(reg_n, reg_m, true), true);
            ir.SetExtendedRegister(d, result);
        });
    }
    return true;
}

bool ArmTranslatorVisitor::vfp2_VDIV(Cond cond, bool D, size_t Vn, size_t Vd, bool sz, bool N, bool M, size_t Vm) {
    ExtReg d = ToExtReg(sz, Vd, D);
    ExtReg n = ToExtReg(sz, Vn, N);
    ExtReg m = ToExtReg(sz, Vm, M);
    // VDIV.{F32,F64} <{S,D}d>, <{S,D}n>, <{S,D}m>
    if (ConditionPassed(cond)) {
        return EmitVfpVectorOperation(sz, d, n, m, [sz, this](ExtReg d, ExtReg n, ExtReg m) {
            auto reg_n = ir.GetExtendedRegister(n);
            auto reg_m = ir.GetExtendedRegister(m);
            auto result = sz
                          ? ir.FPDiv64(reg_n, reg_m, true)
                          : ir.FPDiv32(reg_n, reg_m, true);
            ir.SetExtendedRegister(d, result);
        });
    }
    return true;
}

bool ArmTranslatorVisitor::vfp2_VMOV_u32_f64(Cond cond, size_t Vd, Reg t, bool D) {
    ExtReg d = ToExtReg(true, Vd, D);
    if (t == Reg::PC)
        return UnpredictableInstruction();
    // VMOV.32 <Dd[0]>, <Rt>
    if (ConditionPassed(cond)) {
        auto d_f64 = ir.GetExtendedRegister(d);
        auto t_u32 = ir.GetRegister(t);

        auto d_u64 = ir.TransferFromFP64(d_f64);
        auto result = ir.Pack2x32To1x64(t_u32, ir.MostSignificantWord(d_u64).result);

        ir.SetExtendedRegister(d, ir.TransferToFP64(result));
    }
    return true;
}

bool ArmTranslatorVisitor::vfp2_VMOV_f64_u32(Cond cond, size_t Vn, Reg t, bool N) {
    ExtReg n = ToExtReg(true, Vn, N);
    if (t == Reg::PC)
        return UnpredictableInstruction();
    // VMOV.32 <Rt>, <Dn[0]>
    if (ConditionPassed(cond)) {
        auto n_f64 = ir.GetExtendedRegister(n);
        ir.SetRegister(t, ir.LeastSignificantWord(ir.TransferFromFP64(n_f64)));
    }
    return true;
}

bool ArmTranslatorVisitor::vfp2_VMOV_u32_f32(Cond cond, size_t Vn, Reg t, bool N) {
    ExtReg n = ToExtReg(false, Vn, N);
    if (t == Reg::PC)
        return UnpredictableInstruction();
    // VMOV <Sn>, <Rt>
    if (ConditionPassed(cond)) {
        ir.SetExtendedRegister(n, ir.TransferToFP32(ir.GetRegister(t)));
    }
    return true;
}

bool ArmTranslatorVisitor::vfp2_VMOV_f32_u32(Cond cond, size_t Vn, Reg t, bool N) {
    ExtReg n = ToExtReg(false, Vn, N);
    if (t == Reg::PC)
        return UnpredictableInstruction();
    // VMOV <Rt>, <Sn>
    if (ConditionPassed(cond)) {
        ir.SetRegister(t, ir.TransferFromFP32(ir.GetExtendedRegister(n)));
    }
    return true;
}

bool ArmTranslatorVisitor::vfp2_VMOV_2u32_2f32(Cond cond, Reg t2, Reg t, bool M, size_t Vm) {
    ExtReg m = ToExtReg(false, Vm, M);
    if (t == Reg::PC || t2 == Reg::PC || m == ExtReg::S31)
        return UnpredictableInstruction();
    // VMOV <Sm>, <Sm1>, <Rt>, <Rt2>
    if (ConditionPassed(cond)) {
        ir.SetExtendedRegister(m, ir.TransferToFP32(ir.GetRegister(t)));
        ir.SetExtendedRegister(m+1, ir.TransferToFP32(ir.GetRegister(t2)));
    }
    return true;
}

bool ArmTranslatorVisitor::vfp2_VMOV_2f32_2u32(Cond cond, Reg t2, Reg t, bool M, size_t Vm) {
    ExtReg m = ToExtReg(false, Vm, M);
    if (t == Reg::PC || t2 == Reg::PC || m == ExtReg::S31)
        return UnpredictableInstruction();
    if (t == t2)
        return UnpredictableInstruction();
    // VMOV <Rt>, <Rt2>, <Sm>, <Sm1>
    if (ConditionPassed(cond)) {
        ir.SetRegister(t, ir.TransferFromFP32(ir.GetExtendedRegister(m)));
        ir.SetRegister(t2, ir.TransferFromFP32(ir.GetExtendedRegister(m+1)));
    }
    return true;
}

bool ArmTranslatorVisitor::vfp2_VMOV_2u32_f64(Cond cond, Reg t2, Reg t, bool M, size_t Vm) {
    ExtReg m = ToExtReg(true, Vm, M);
    if (t == Reg::PC || t2 == Reg::PC || m == ExtReg::S31)
        return UnpredictableInstruction();
    // VMOV<c> <Dm>, <Rt>, <Rt2>
    if (ConditionPassed(cond)) {
        auto value = ir.Pack2x32To1x64(ir.GetRegister(t), ir.GetRegister(t2));
        ir.SetExtendedRegister(m, ir.TransferToFP64(value));
    }
    return true;
}

bool ArmTranslatorVisitor::vfp2_VMOV_f64_2u32(Cond cond, Reg t2, Reg t, bool M, size_t Vm) {
    ExtReg m = ToExtReg(true, Vm, M);
    if (t == Reg::PC || t2 == Reg::PC || m == ExtReg::S31)
        return UnpredictableInstruction();
    if (t == t2)
        return UnpredictableInstruction();
    // VMOV<c> <Rt>, <Rt2>, <Dm>
    if (ConditionPassed(cond)) {
        auto value = ir.TransferFromFP64(ir.GetExtendedRegister(m));
        ir.SetRegister(t, ir.LeastSignificantWord(value));
        ir.SetRegister(t2, ir.MostSignificantWord(value).result);
    }
    return true;
}

bool ArmTranslatorVisitor::vfp2_VMOV_reg(Cond cond, bool D, size_t Vd, bool sz, bool M, size_t Vm) {
    ExtReg d = ToExtReg(sz, Vd, D);
    ExtReg m = ToExtReg(sz, Vm, M);
    // VMOV.{F32,F64} <{S,D}d>, <{S,D}m>
    if (ConditionPassed(cond)) {
        return EmitVfpVectorOperation(sz, d, m, [this](ExtReg d, ExtReg m) {
            ir.SetExtendedRegister(d, ir.GetExtendedRegister(m));
        });
    }
    return true;
}

bool ArmTranslatorVisitor::vfp2_VABS(Cond cond, bool D, size_t Vd, bool sz, bool M, size_t Vm) {
    ExtReg d = ToExtReg(sz, Vd, D);
    ExtReg m = ToExtReg(sz, Vm, M);
    // VABS.{F32,F64} <{S,D}d>, <{S,D}m>
    if (ConditionPassed(cond)) {
        return EmitVfpVectorOperation(sz, d, m, [sz, this](ExtReg d, ExtReg m) {
            auto reg_m = ir.GetExtendedRegister(m);
            auto result = sz
                          ? ir.FPAbs64(reg_m)
                          : ir.FPAbs32(reg_m);
            ir.SetExtendedRegister(d, result);
        });
    }
    return true;
}

bool ArmTranslatorVisitor::vfp2_VNEG(Cond cond, bool D, size_t Vd, bool sz, bool M, size_t Vm) {
    ExtReg d = ToExtReg(sz, Vd, D);
    ExtReg m = ToExtReg(sz, Vm, M);
    // VNEG.{F32,F64} <{S,D}d>, <{S,D}m>
    if (ConditionPassed(cond)) {
        return EmitVfpVectorOperation(sz, d, m, [sz, this](ExtReg d, ExtReg m) {
            auto reg_m = ir.GetExtendedRegister(m);
            auto result = sz
                          ? ir.FPNeg64(reg_m)
                          : ir.FPNeg32(reg_m);
            ir.SetExtendedRegister(d, result);
        });
    }
    return true;
}

bool ArmTranslatorVisitor::vfp2_VSQRT(Cond cond, bool D, size_t Vd, bool sz, bool M, size_t Vm) {
    ExtReg d = ToExtReg(sz, Vd, D);
    ExtReg m = ToExtReg(sz, Vm, M);
    // VSQRT.{F32,F64} <{S,D}d>, <{S,D}m>
    if (ConditionPassed(cond)) {
        return EmitVfpVectorOperation(sz, d, m, [sz, this](ExtReg d, ExtReg m) {
            auto reg_m = ir.GetExtendedRegister(m);
            auto result = sz
                          ? ir.FPSqrt64(reg_m)
                          : ir.FPSqrt32(reg_m);
            ir.SetExtendedRegister(d, result);
        });
    }
    return true;
}

bool ArmTranslatorVisitor::vfp2_VCVT_f_to_f(Cond cond, bool D, size_t Vd, bool sz, bool M, size_t Vm) {
    ExtReg d = ToExtReg(!sz, Vd, D); // Destination is of opposite size to source
    ExtReg m = ToExtReg(sz, Vm, M);
    // VCVT.F64.F32 <Sd> <Dm>
    // VCVT.F32.F64 <Dd> <Sm>
    if (ConditionPassed(cond)) {
        auto reg_m = ir.GetExtendedRegister(m);
        auto result = sz
                      ? ir.FPDoubleToSingle(reg_m, true)
                      : ir.FPSingleToDouble(reg_m, true);
        ir.SetExtendedRegister(d, result);
    }
    return true;
}

bool ArmTranslatorVisitor::vfp2_VCVT_to_float(Cond cond, bool D, size_t Vd, bool sz, bool is_signed, bool M, size_t Vm) {
    ExtReg d = ToExtReg(sz, Vd, D);
    ExtReg m = ToExtReg(false, Vm, M);
    bool round_to_nearest = false;
    // VCVT.F32.{S32,U32} <Sd>, <Sm>
    // VCVT.F64.{S32,U32} <Sd>, <Dm>
    if (ConditionPassed(cond)) {
        auto reg_m = ir.GetExtendedRegister(m);
        auto result = sz
                      ? is_signed
                        ? ir.FPS32ToDouble(reg_m, round_to_nearest, true)
                        : ir.FPU32ToDouble(reg_m, round_to_nearest, true)
                      : is_signed
                        ? ir.FPS32ToSingle(reg_m, round_to_nearest, true)
                        : ir.FPU32ToSingle(reg_m, round_to_nearest, true);
        ir.SetExtendedRegister(d, result);
    }
    return true;
}

bool ArmTranslatorVisitor::vfp2_VCVT_to_u32(Cond cond, bool D, size_t Vd, bool sz, bool round_towards_zero, bool M, size_t Vm) {
    ExtReg d = ToExtReg(false, Vd, D);
    ExtReg m = ToExtReg(sz, Vm, M);
    // VCVT{,R}.U32.F32 <Sd>, <Sm>
    // VCVT{,R}.U32.F64 <Sd>, <Dm>
    if (ConditionPassed(cond)) {
        auto reg_m = ir.GetExtendedRegister(m);
        auto result = sz
                      ? ir.FPDoubleToU32(reg_m, round_towards_zero, true)
                      : ir.FPSingleToU32(reg_m, round_towards_zero, true);
        ir.SetExtendedRegister(d, result);
    }
    return true;
}

bool ArmTranslatorVisitor::vfp2_VCVT_to_s32(Cond cond, bool D, size_t Vd, bool sz, bool round_towards_zero, bool M, size_t Vm) {
    ExtReg d = ToExtReg(false, Vd, D);
    ExtReg m = ToExtReg(sz, Vm, M);
    // VCVT{,R}.S32.F32 <Sd>, <Sm>
    // VCVT{,R}.S32.F64 <Sd>, <Dm>
    if (ConditionPassed(cond)) {
        auto reg_m = ir.GetExtendedRegister(m);
        auto result = sz
                      ? ir.FPDoubleToS32(reg_m, round_towards_zero, true)
                      : ir.FPSingleToS32(reg_m, round_towards_zero, true);
        ir.SetExtendedRegister(d, result);
    }
    return true;
}

bool ArmTranslatorVisitor::vfp2_VCMP(Cond cond, bool D, size_t Vd, bool sz, bool E, bool M, size_t Vm) {
    ExtReg d = ToExtReg(sz, Vd, D);
    ExtReg m = ToExtReg(sz, Vm, M);
    bool exc_on_qnan = E;
    // VCMP{E}.F32 <Sd>, <Sm>
    // VCMP{E}.F64 <Dd>, <Dm>
    if (ConditionPassed(cond)) {
        auto reg_d = ir.GetExtendedRegister(d);
        auto reg_m = ir.GetExtendedRegister(m);
        if (sz) {
            ir.FPCompare64(reg_d, reg_m, exc_on_qnan, true);
        } else {
            ir.FPCompare32(reg_d, reg_m, exc_on_qnan, true);
        }
    }
    return true;
}

bool ArmTranslatorVisitor::vfp2_VCMP_zero(Cond cond, bool D, size_t Vd, bool sz, bool E) {
    ExtReg d = ToExtReg(sz, Vd, D);
    bool exc_on_qnan = E;
    // VCMP{E}.F32 <Sd>, #0.0
    // VCMP{E}.F64 <Dd>, #0.0
    if (ConditionPassed(cond)) {
        auto reg_d = ir.GetExtendedRegister(d);
        auto zero = sz
                    ? ir.TransferToFP64(ir.Imm64(0))
                    : ir.TransferToFP32(ir.Imm32(0));
        if (sz) {
            ir.FPCompare64(reg_d, zero, exc_on_qnan, true);
        } else {
            ir.FPCompare32(reg_d, zero, exc_on_qnan, true);
        }
    }
    return true;
}

bool ArmTranslatorVisitor::vfp2_VMSR(Cond cond, Reg t) {
    if (t == Reg::PC)
        return UnpredictableInstruction();

    // VMSR FPSCR, <Rt>
    if (ConditionPassed(cond)) {
        ir.PushRSB(ir.current_location.AdvancePC(4)); // TODO: Replace this with a local cache.
        ir.SetFpscr(ir.GetRegister(t));
        ir.BranchWritePC(ir.Imm32(ir.current_location.PC() + 4));
        ir.SetTerm(IR::Term::PopRSBHint{});
        return false;
    }
    return true;
}

bool ArmTranslatorVisitor::vfp2_VMRS(Cond cond, Reg t) {
    // VMRS <Rt>, FPSCR
    if (ConditionPassed(cond)) {
        if (t == Reg::R15) {
            // This encodes ASPR_nzcv access
            auto nzcv = ir.GetFpscrNZCV();
            ir.SetCpsrNZCV(nzcv);
        } else {
            ir.SetRegister(t, ir.GetFpscr());
        }
    }
    return true;
}

bool ArmTranslatorVisitor::vfp2_VPOP(Cond cond, bool D, size_t Vd, bool sz, Imm8 imm8) {
    const ExtReg d = ToExtReg(sz, Vd, D);
    const size_t regs = sz ? imm8 >> 1 : imm8;

    if (regs == 0 || RegNumber(d)+regs > 32)
        return UnpredictableInstruction();
    if (sz && regs > 16)
        return UnpredictableInstruction();

    // VPOP.{F32,F64} <list>
    if (ConditionPassed(cond)) {
        auto address = ir.GetRegister(Reg::SP);

        for (size_t i = 0; i < regs; ++i) {
            if (sz) {
                auto lo = ir.ReadMemory32(address);
                address = ir.Add(address, ir.Imm32(4));
                auto hi = ir.ReadMemory32(address);
                address = ir.Add(address, ir.Imm32(4));
                if (ir.current_location.EFlag()) std::swap(lo, hi);
                ir.SetExtendedRegister(d + i, ir.TransferToFP64(ir.Pack2x32To1x64(lo, hi)));
            } else {
                auto res = ir.ReadMemory32(address);
                ir.SetExtendedRegister(d + i, ir.TransferToFP32(res));
                address = ir.Add(address, ir.Imm32(4));
            }
        }

        ir.SetRegister(Reg::SP, address);
    }
    return true;
}

bool ArmTranslatorVisitor::vfp2_VPUSH(Cond cond, bool D, size_t Vd, bool sz, Imm8 imm8) {
    u32 imm32 = imm8 << 2;
    const ExtReg d = ToExtReg(sz, Vd, D);
    const size_t regs = sz ? imm8 >> 1 : imm8;

    if (regs == 0 || RegNumber(d)+regs > 32)
        return UnpredictableInstruction();
    if (sz && regs > 16)
        return UnpredictableInstruction();

    // VPUSH.{F32,F64} <list>
    if (ConditionPassed(cond)) {
        auto address = ir.Sub(ir.GetRegister(Reg::SP), ir.Imm32(imm32));
        ir.SetRegister(Reg::SP, address);

        for (size_t i = 0; i < regs; ++i) {
            if (sz) {
                const auto d_u64 = ir.TransferFromFP64(ir.GetExtendedRegister(d + i));
                auto lo = ir.LeastSignificantWord(d_u64);
                auto hi = ir.MostSignificantWord(d_u64).result;
                if (ir.current_location.EFlag()) std::swap(lo, hi);
                ir.WriteMemory32(address, lo);
                address = ir.Add(address, ir.Imm32(4));
                ir.WriteMemory32(address, hi);
                address = ir.Add(address, ir.Imm32(4));
            } else {
                ir.WriteMemory32(address, ir.TransferFromFP32(ir.GetExtendedRegister(d + i)));
                address = ir.Add(address, ir.Imm32(4));
            }
        }
    }
    return true;
}

bool ArmTranslatorVisitor::vfp2_VLDR(Cond cond, bool U, bool D, Reg n, size_t Vd, bool sz, Imm8 imm8) {
    u32 imm32 = imm8 << 2;
    ExtReg d = ToExtReg(sz, Vd, D);
    // VLDR <{S,D}d>, [<Rn>, #+/-<imm32>]
    if (ConditionPassed(cond)) {
        auto base = n == Reg::PC ? ir.Imm32(ir.AlignPC(4)) : ir.GetRegister(n);
        auto address = U ? ir.Add(base, ir.Imm32(imm32)) : ir.Sub(base, ir.Imm32(imm32));
        if (sz) {
            auto lo = ir.ReadMemory32(address);
            auto hi = ir.ReadMemory32(ir.Add(address, ir.Imm32(4)));
            if (ir.current_location.EFlag()) std::swap(lo, hi);
            ir.SetExtendedRegister(d, ir.TransferToFP64(ir.Pack2x32To1x64(lo, hi)));
        } else {
            ir.SetExtendedRegister(d, ir.TransferToFP32(ir.ReadMemory32(address)));
        }
    }
    return true;
}

bool ArmTranslatorVisitor::vfp2_VSTR(Cond cond, bool U, bool D, Reg n, size_t Vd, bool sz, Imm8 imm8) {
    u32 imm32 = imm8 << 2;
    ExtReg d = ToExtReg(sz, Vd, D);
    // VSTR <{S,D}d>, [<Rn>, #+/-<imm32>]
    if (ConditionPassed(cond)) {
        auto base = n == Reg::PC ? ir.Imm32(ir.AlignPC(4)) : ir.GetRegister(n);
        auto address = U ? ir.Add(base, ir.Imm32(imm32)) : ir.Sub(base, ir.Imm32(imm32));
        if (sz) {
            auto d_u64 = ir.TransferFromFP64(ir.GetExtendedRegister(d));
            auto lo = ir.LeastSignificantWord(d_u64);
            auto hi = ir.MostSignificantWord(d_u64).result;
            if (ir.current_location.EFlag()) std::swap(lo, hi);
            ir.WriteMemory32(address, lo);
            ir.WriteMemory32(ir.Add(address, ir.Imm32(4)), hi);
        } else {
            ir.WriteMemory32(address, ir.TransferFromFP32(ir.GetExtendedRegister(d)));
        }
    }
    return true;
}

bool ArmTranslatorVisitor::vfp2_VSTM_a1(Cond cond, bool p, bool u, bool D, bool w, Reg n, size_t Vd, Imm8 imm8) {
    if (!p && !u && !w)
        ASSERT_MSG(false, "Decode error");
    if (p && !w)
        ASSERT_MSG(false, "Decode error");
    if (p == u && w)
        return arm_UDF();
    if (n == Reg::PC && w)
        return UnpredictableInstruction();

    ExtReg d = ToExtReg(true, Vd, D);
    u32 imm32 = imm8 << 2;
    size_t regs = imm8 / 2;

    if (regs == 0 || regs > 16 || Arm::RegNumber(d)+regs > 32)
        return UnpredictableInstruction();

    // VSTM<mode>.F64 <Rn>{!}, <list of double registers>
    if (ConditionPassed(cond)) {
        auto address = u ? ir.GetRegister(n) : ir.Sub(ir.GetRegister(n), ir.Imm32(imm32));
        if (w)
            ir.SetRegister(n, u ? ir.Add(address, ir.Imm32(imm32)) : address);
        for (size_t i = 0; i < regs; i++) {
            auto value = ir.TransferFromFP64(ir.GetExtendedRegister(d + i));
            auto word1 = ir.LeastSignificantWord(value);
            auto word2 = ir.MostSignificantWord(value).result;
            if (ir.current_location.EFlag()) std::swap(word1, word2);
            ir.WriteMemory32(address, word1);
            address = ir.Add(address, ir.Imm32(4));
            ir.WriteMemory32(address, word2);
            address = ir.Add(address, ir.Imm32(4));
        }
    }
    return true;
}

bool ArmTranslatorVisitor::vfp2_VSTM_a2(Cond cond, bool p, bool u, bool D, bool w, Reg n, size_t Vd, Imm8 imm8) {
    if (!p && !u && !w)
        ASSERT_MSG(false, "Decode error");
    if (p && !w)
        ASSERT_MSG(false, "Decode error");
    if (p == u && w)
        return arm_UDF();
    if (n == Reg::PC && w)
        return UnpredictableInstruction();

    ExtReg d = ToExtReg(false, Vd, D);
    u32 imm32 = imm8 << 2;
    size_t regs = imm8;

    if (regs == 0 || Arm::RegNumber(d)+regs > 32)
        return UnpredictableInstruction();

    // VSTM<mode>.F32 <Rn>{!}, <list of single registers>
    if (ConditionPassed(cond)) {
        auto address = u ? ir.GetRegister(n) : ir.Sub(ir.GetRegister(n), ir.Imm32(imm32));
        if (w)
            ir.SetRegister(n, u ? ir.Add(address, ir.Imm32(imm32)) : address);
        for (size_t i = 0; i < regs; i++) {
            auto word = ir.TransferFromFP32(ir.GetExtendedRegister(d + i));
            ir.WriteMemory32(address, word);
            address = ir.Add(address, ir.Imm32(4));
        }
    }
    return true;
}

bool ArmTranslatorVisitor::vfp2_VLDM_a1(Cond cond, bool p, bool u, bool D, bool w, Reg n, size_t Vd, Imm8 imm8) {
    if (!p && !u && !w)
        ASSERT_MSG(false, "Decode error");
    if (p && !w)
        ASSERT_MSG(false, "Decode error");
    if (p == u && w)
        return arm_UDF();
    if (n == Reg::PC && w)
        return UnpredictableInstruction();

    ExtReg d = ToExtReg(true, Vd, D);
    u32 imm32 = imm8 << 2;
    size_t regs = imm8 / 2;

    if (regs == 0 || regs > 16 || Arm::RegNumber(d)+regs > 32)
        return UnpredictableInstruction();

    // VLDM<mode>.F64 <Rn>{!}, <list of double registers>
    if (ConditionPassed(cond)) {
        auto address = u ? ir.GetRegister(n) : ir.Sub(ir.GetRegister(n), ir.Imm32(imm32));
        if (w)
            ir.SetRegister(n, u ? ir.Add(address, ir.Imm32(imm32)) : address);
        for (size_t i = 0; i < regs; i++) {
            auto word1 = ir.ReadMemory32(address);
            address = ir.Add(address, ir.Imm32(4));
            auto word2 = ir.ReadMemory32(address);
            address = ir.Add(address, ir.Imm32(4));
            if (ir.current_location.EFlag()) std::swap(word1, word2);
            ir.SetExtendedRegister(d + i, ir.TransferToFP64(ir.Pack2x32To1x64(word1, word2)));
        }
    }
    return true;
}

bool ArmTranslatorVisitor::vfp2_VLDM_a2(Cond cond, bool p, bool u, bool D, bool w, Reg n, size_t Vd, Imm8 imm8) {
    if (!p && !u && !w)
        ASSERT_MSG(false, "Decode error");
    if (p && !w)
        ASSERT_MSG(false, "Decode error");
    if (p == u && w)
        return arm_UDF();
    if (n == Reg::PC && w)
        return UnpredictableInstruction();

    ExtReg d = ToExtReg(false, Vd, D);
    u32 imm32 = imm8 << 2;
    size_t regs = imm8;

    if (regs == 0 || Arm::RegNumber(d)+regs > 32)
        return UnpredictableInstruction();

    // VLDM<mode>.F32 <Rn>{!}, <list of single registers>
    if (ConditionPassed(cond)) {
        auto address = u ? ir.GetRegister(n) : ir.Sub(ir.GetRegister(n), ir.Imm32(imm32));
        if (w)
            ir.SetRegister(n, u ? ir.Add(address, ir.Imm32(imm32)) : address);
        for (size_t i = 0; i < regs; i++) {
            auto word = ir.ReadMemory32(address);
            address = ir.Add(address, ir.Imm32(4));
            ir.SetExtendedRegister(d + i, ir.TransferToFP32(word));
        }
    }
    return true;
}

} // namespace Arm
} // namespace Dynarmic