const std = @import("../std.zig");
const CpuFeature = std.Target.Cpu.Feature;
const CpuModel = std.Target.Cpu.Model;

pub const Feature = enum {
    @"64bit",
    a,
    c,
    d,
    e,
    f,
    m,
    relax,
    reserve_x1,
    reserve_x10,
    reserve_x11,
    reserve_x12,
    reserve_x13,
    reserve_x14,
    reserve_x15,
    reserve_x16,
    reserve_x17,
    reserve_x18,
    reserve_x19,
    reserve_x2,
    reserve_x20,
    reserve_x21,
    reserve_x22,
    reserve_x23,
    reserve_x24,
    reserve_x25,
    reserve_x26,
    reserve_x27,
    reserve_x28,
    reserve_x29,
    reserve_x3,
    reserve_x30,
    reserve_x31,
    reserve_x4,
    reserve_x5,
    reserve_x6,
    reserve_x7,
    reserve_x8,
    reserve_x9,
    rvc_hints,
};

pub usingnamespace CpuFeature.feature_set_fns(Feature);

pub const all_features = blk: {
    const len = @typeInfo(Feature).Enum.fields.len;
    std.debug.assert(len <= CpuFeature.Set.needed_bit_count);
    var result: [len]CpuFeature = undefined;
    result[@enumToInt(Feature.@"64bit")] = .{
        .llvm_name = "64bit",
        .description = "Implements RV64",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.a)] = .{
        .llvm_name = "a",
        .description = "'A' (Atomic Instructions)",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.c)] = .{
        .llvm_name = "c",
        .description = "'C' (Compressed Instructions)",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.d)] = .{
        .llvm_name = "d",
        .description = "'D' (Double-Precision Floating-Point)",
        .dependencies = featureSet(&[_]Feature{
            .f,
        }),
    };
    result[@enumToInt(Feature.e)] = .{
        .llvm_name = "e",
        .description = "Implements RV32E (provides 16 rather than 32 GPRs)",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.f)] = .{
        .llvm_name = "f",
        .description = "'F' (Single-Precision Floating-Point)",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.m)] = .{
        .llvm_name = "m",
        .description = "'M' (Integer Multiplication and Division)",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.relax)] = .{
        .llvm_name = "relax",
        .description = "Enable Linker relaxation.",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.reserve_x1)] = .{
        .llvm_name = "reserve-x1",
        .description = "Reserve X1",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.reserve_x10)] = .{
        .llvm_name = "reserve-x10",
        .description = "Reserve X10",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.reserve_x11)] = .{
        .llvm_name = "reserve-x11",
        .description = "Reserve X11",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.reserve_x12)] = .{
        .llvm_name = "reserve-x12",
        .description = "Reserve X12",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.reserve_x13)] = .{
        .llvm_name = "reserve-x13",
        .description = "Reserve X13",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.reserve_x14)] = .{
        .llvm_name = "reserve-x14",
        .description = "Reserve X14",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.reserve_x15)] = .{
        .llvm_name = "reserve-x15",
        .description = "Reserve X15",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.reserve_x16)] = .{
        .llvm_name = "reserve-x16",
        .description = "Reserve X16",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.reserve_x17)] = .{
        .llvm_name = "reserve-x17",
        .description = "Reserve X17",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.reserve_x18)] = .{
        .llvm_name = "reserve-x18",
        .description = "Reserve X18",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.reserve_x19)] = .{
        .llvm_name = "reserve-x19",
        .description = "Reserve X19",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.reserve_x2)] = .{
        .llvm_name = "reserve-x2",
        .description = "Reserve X2",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.reserve_x20)] = .{
        .llvm_name = "reserve-x20",
        .description = "Reserve X20",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.reserve_x21)] = .{
        .llvm_name = "reserve-x21",
        .description = "Reserve X21",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.reserve_x22)] = .{
        .llvm_name = "reserve-x22",
        .description = "Reserve X22",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.reserve_x23)] = .{
        .llvm_name = "reserve-x23",
        .description = "Reserve X23",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.reserve_x24)] = .{
        .llvm_name = "reserve-x24",
        .description = "Reserve X24",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.reserve_x25)] = .{
        .llvm_name = "reserve-x25",
        .description = "Reserve X25",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.reserve_x26)] = .{
        .llvm_name = "reserve-x26",
        .description = "Reserve X26",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.reserve_x27)] = .{
        .llvm_name = "reserve-x27",
        .description = "Reserve X27",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.reserve_x28)] = .{
        .llvm_name = "reserve-x28",
        .description = "Reserve X28",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.reserve_x29)] = .{
        .llvm_name = "reserve-x29",
        .description = "Reserve X29",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.reserve_x3)] = .{
        .llvm_name = "reserve-x3",
        .description = "Reserve X3",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.reserve_x30)] = .{
        .llvm_name = "reserve-x30",
        .description = "Reserve X30",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.reserve_x31)] = .{
        .llvm_name = "reserve-x31",
        .description = "Reserve X31",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.reserve_x4)] = .{
        .llvm_name = "reserve-x4",
        .description = "Reserve X4",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.reserve_x5)] = .{
        .llvm_name = "reserve-x5",
        .description = "Reserve X5",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.reserve_x6)] = .{
        .llvm_name = "reserve-x6",
        .description = "Reserve X6",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.reserve_x7)] = .{
        .llvm_name = "reserve-x7",
        .description = "Reserve X7",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.reserve_x8)] = .{
        .llvm_name = "reserve-x8",
        .description = "Reserve X8",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.reserve_x9)] = .{
        .llvm_name = "reserve-x9",
        .description = "Reserve X9",
        .dependencies = featureSet(&[_]Feature{}),
    };
    result[@enumToInt(Feature.rvc_hints)] = .{
        .llvm_name = "rvc-hints",
        .description = "Enable RVC Hint Instructions.",
        .dependencies = featureSet(&[_]Feature{}),
    };
    const ti = @typeInfo(Feature);
    for (result) |*elem, i| {
        elem.index = i;
        elem.name = ti.Enum.fields[i].name;
    }
    break :blk result;
};

pub const cpu = struct {
    pub const baseline_rv32 = CpuModel{
        .name = "baseline_rv32",
        .llvm_name = null,
        .features = featureSet(&[_]Feature{
            .a,
            .c,
            .d,
            .f,
            .m,
        }),
    };

    pub const baseline_rv64 = CpuModel{
        .name = "baseline_rv64",
        .llvm_name = null,
        .features = featureSet(&[_]Feature{
            .@"64bit",
            .a,
            .c,
            .d,
            .f,
            .m,
        }),
    };

    pub const generic_rv32 = CpuModel{
        .name = "generic_rv32",
        .llvm_name = null,
        .features = featureSet(&[_]Feature{
            .rvc_hints,
        }),
    };
    pub const generic_rv64 = CpuModel{
        .name = "generic_rv64",
        .llvm_name = null,
        .features = featureSet(&[_]Feature{
            .@"64bit",
            .rvc_hints,
        }),
    };
};

/// All riscv CPUs, sorted alphabetically by name.
/// TODO: Replace this with usage of `std.meta.declList`. It does work, but stage1
/// compiler has inefficient memory and CPU usage, affecting build times.
pub const all_cpus = &[_]*const CpuModel{
    &cpu.baseline_rv32,
    &cpu.baseline_rv64,
    &cpu.generic_rv32,
    &cpu.generic_rv64,
};