1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141

//! Performs autodetection of the host for the purposes of running
//! Cranelift to generate code to run on the same machine.

#![deny(
    missing_docs,
    trivial_numeric_casts,
    unused_extern_crates,
    unstable_features
)]
#![warn(unused_import_braces)]
#![cfg_attr(feature = "clippy", plugin(clippy(conf_file = "../../clippy.toml")))]
#![cfg_attr(feature = "cargo-clippy", allow(clippy::new_without_default))]
#![cfg_attr(
    feature = "cargo-clippy",
    warn(
        clippy::float_arithmetic,
        clippy::mut_mut,
        clippy::nonminimal_bool,
        clippy::option_map_unwrap_or,
        clippy::option_map_unwrap_or_else,
        clippy::print_stdout,
        clippy::unicode_not_nfc,
        clippy::use_self
    )
)]
#![no_std]

use cranelift_codegen::isa;
use target_lexicon::Triple;

#[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
use raw_cpuid::CpuId;

/// Return an `isa` builder configured for the current host
/// machine, or `Err(())` if the host machine is not supported
/// in the current configuration.
pub fn builder() -> Result<isa::Builder, &'static str> {
    let mut isa_builder = isa::lookup(Triple::host()).map_err(|err| match err {
        isa::LookupError::SupportDisabled => "support for architecture disabled at compile time",
        isa::LookupError::Unsupported => "unsupported architecture",
    })?;

    if cfg!(any(target_arch = "x86", target_arch = "x86_64")) {
        parse_x86_cpuid(&mut isa_builder)?;
    }

    Ok(isa_builder)
}

#[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
fn parse_x86_cpuid(isa_builder: &mut isa::Builder) -> Result<(), &'static str> {
    use cranelift_codegen::settings::Configurable;
    let cpuid = CpuId::new();

    if let Some(info) = cpuid.get_feature_info() {
        if !info.has_sse2() {
            return Err("x86 support requires SSE2");
        }
        if info.has_sse3() {
            isa_builder.enable("has_sse3").unwrap();
        }
        if info.has_ssse3() {
            isa_builder.enable("has_ssse3").unwrap();
        }
        if info.has_sse41() {
            isa_builder.enable("has_sse41").unwrap();
        }
        if info.has_sse42() {
            isa_builder.enable("has_sse42").unwrap();
        }
        if info.has_popcnt() {
            isa_builder.enable("has_popcnt").unwrap();
        }
        if info.has_avx() {
            isa_builder.enable("has_avx").unwrap();
        }
    }
    if let Some(info) = cpuid.get_extended_feature_info() {
        if info.has_bmi1() {
            isa_builder.enable("has_bmi1").unwrap();
        }
        if info.has_bmi2() {
            isa_builder.enable("has_bmi2").unwrap();
        }
        if info.has_avx2() {
            isa_builder.enable("has_avx2").unwrap();
        }
        if info.has_avx512dq() {
            isa_builder.enable("has_avx512dq").unwrap();
        }
        if info.has_avx512vl() {
            isa_builder.enable("has_avx512vl").unwrap();
        }
        if info.has_avx512f() {
            isa_builder.enable("has_avx512f").unwrap();
        }
    }
    if let Some(info) = cpuid.get_extended_function_info() {
        if info.has_lzcnt() {
            isa_builder.enable("has_lzcnt").unwrap();
        }
    }
    Ok(())
}

#[cfg(not(any(target_arch = "x86", target_arch = "x86_64")))]
fn parse_x86_cpuid(_isa_builder: &mut isa::Builder) -> Result<(), &'static str> {
    unreachable!();
}

#[cfg(test)]
mod tests {
    use super::builder;
    use cranelift_codegen::isa::CallConv;
    use cranelift_codegen::settings;

    #[test]
    fn test() {
        if let Ok(isa_builder) = builder() {
            let flag_builder = settings::builder();
            let isa = isa_builder.finish(settings::Flags::new(flag_builder));
            if cfg!(any(unix, target_os = "nebulet")) {
                assert_eq!(isa.default_call_conv(), CallConv::SystemV);
            } else if cfg!(windows) {
                assert_eq!(isa.default_call_conv(), CallConv::WindowsFastcall);
            }
            if cfg!(target_pointer_width = "64") {
                assert_eq!(isa.pointer_bits(), 64);
            }
            if cfg!(target_pointer_width = "32") {
                assert_eq!(isa.pointer_bits(), 32);
            }
            if cfg!(target_pointer_width = "16") {
                assert_eq!(isa.pointer_bits(), 16);
            }
        }
    }
}

/// Version number of this crate.
pub const VERSION: &str = env!("CARGO_PKG_VERSION");