detectNativeCpuAndFeatures

fn detectNativeCpuAndFeatures(io: Io, cpu_arch: Target.Cpu.Arch, os: Target.Os, query: Target.Query) ?Target.Cpu {
    // Here we switch on a comptime value rather than `cpu_arch`. This is valid because `cpu_arch`,
    // although it is a runtime value, is guaranteed to be one of the architectures in the set
    // of the respective switch prong.
    switch (builtin.cpu.arch) {
        .loongarch32, .loongarch64 => return @import("system/loongarch.zig").detectNativeCpuAndFeatures(cpu_arch, os, query),
        .x86_64, .x86 => return @import("system/x86.zig").detectNativeCpuAndFeatures(cpu_arch, os, query),
        else => {},
    }

    switch (builtin.os.tag) {
        .linux => return linux.detectNativeCpuAndFeatures(io),
        .macos => return darwin.macos.detectNativeCpuAndFeatures(),
        .windows => return windows.detectNativeCpuAndFeatures(),
        else => {},
    }

    // This architecture does not have CPU model & feature detection yet.
    // See https://github.com/ziglang/zig/issues/4591
    return null;
}