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| 1 | +// Vendored from https://github.com/bytecodealliance/wasmtime/blob/b58a197d33f044193c3d608010f5e6ec394ac07e/cranelift/native/src/lib.rs |
| 2 | +// which is licensed as |
| 3 | +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| 4 | +// unlike rustc_codegen_cranelift itself. Also applies a small change to remove #![cfg_attr] that |
| 5 | +// rust's CI complains about and to fix formatting to match rustc. |
| 6 | +// FIXME revert back to the external crate with Cranelift 0.93 |
| 7 | +#![allow(warnings)] |
| 8 | + |
| 9 | +//! Performs autodetection of the host for the purposes of running |
| 10 | +//! Cranelift to generate code to run on the same machine. |
| 11 | +
|
| 12 | +#![deny(missing_docs, trivial_numeric_casts, unused_extern_crates, unstable_features)] |
| 13 | +#![warn(unused_import_braces)] |
| 14 | + |
| 15 | +use cranelift_codegen::isa; |
| 16 | +use target_lexicon::Triple; |
| 17 | + |
| 18 | +/// Return an `isa` builder configured for the current host |
| 19 | +/// machine, or `Err(())` if the host machine is not supported |
| 20 | +/// in the current configuration. |
| 21 | +pub fn builder() -> Result<isa::Builder, &'static str> { |
| 22 | + builder_with_options(true) |
| 23 | +} |
| 24 | + |
| 25 | +/// Return an `isa` builder configured for the current host |
| 26 | +/// machine, or `Err(())` if the host machine is not supported |
| 27 | +/// in the current configuration. |
| 28 | +/// |
| 29 | +/// Selects the given backend variant specifically; this is |
| 30 | +/// useful when more than oen backend exists for a given target |
| 31 | +/// (e.g., on x86-64). |
| 32 | +pub fn builder_with_options(infer_native_flags: bool) -> Result<isa::Builder, &'static str> { |
| 33 | + let mut isa_builder = isa::lookup(Triple::host()).map_err(|err| match err { |
| 34 | + isa::LookupError::SupportDisabled => "support for architecture disabled at compile time", |
| 35 | + isa::LookupError::Unsupported => "unsupported architecture", |
| 36 | + })?; |
| 37 | + |
| 38 | + #[cfg(target_arch = "x86_64")] |
| 39 | + { |
| 40 | + use cranelift_codegen::settings::Configurable; |
| 41 | + |
| 42 | + if !std::is_x86_feature_detected!("sse2") { |
| 43 | + return Err("x86 support requires SSE2"); |
| 44 | + } |
| 45 | + |
| 46 | + if !infer_native_flags { |
| 47 | + return Ok(isa_builder); |
| 48 | + } |
| 49 | + |
| 50 | + // These are temporarily enabled by default (see #3810 for |
| 51 | + // more) so that a default-constructed `Flags` can work with |
| 52 | + // default Wasmtime features. Otherwise, the user must |
| 53 | + // explicitly use native flags or turn these on when on x86-64 |
| 54 | + // platforms to avoid a configuration panic. In order for the |
| 55 | + // "enable if detected" logic below to work, we must turn them |
| 56 | + // *off* (differing from the default) and then re-enable below |
| 57 | + // if present. |
| 58 | + isa_builder.set("has_sse3", "false").unwrap(); |
| 59 | + isa_builder.set("has_ssse3", "false").unwrap(); |
| 60 | + isa_builder.set("has_sse41", "false").unwrap(); |
| 61 | + isa_builder.set("has_sse42", "false").unwrap(); |
| 62 | + |
| 63 | + if std::is_x86_feature_detected!("sse3") { |
| 64 | + isa_builder.enable("has_sse3").unwrap(); |
| 65 | + } |
| 66 | + if std::is_x86_feature_detected!("ssse3") { |
| 67 | + isa_builder.enable("has_ssse3").unwrap(); |
| 68 | + } |
| 69 | + if std::is_x86_feature_detected!("sse4.1") { |
| 70 | + isa_builder.enable("has_sse41").unwrap(); |
| 71 | + } |
| 72 | + if std::is_x86_feature_detected!("sse4.2") { |
| 73 | + isa_builder.enable("has_sse42").unwrap(); |
| 74 | + } |
| 75 | + if std::is_x86_feature_detected!("popcnt") { |
| 76 | + isa_builder.enable("has_popcnt").unwrap(); |
| 77 | + } |
| 78 | + if std::is_x86_feature_detected!("avx") { |
| 79 | + isa_builder.enable("has_avx").unwrap(); |
| 80 | + } |
| 81 | + if std::is_x86_feature_detected!("avx2") { |
| 82 | + isa_builder.enable("has_avx2").unwrap(); |
| 83 | + } |
| 84 | + if std::is_x86_feature_detected!("fma") { |
| 85 | + isa_builder.enable("has_fma").unwrap(); |
| 86 | + } |
| 87 | + if std::is_x86_feature_detected!("bmi1") { |
| 88 | + isa_builder.enable("has_bmi1").unwrap(); |
| 89 | + } |
| 90 | + if std::is_x86_feature_detected!("bmi2") { |
| 91 | + isa_builder.enable("has_bmi2").unwrap(); |
| 92 | + } |
| 93 | + if std::is_x86_feature_detected!("avx512bitalg") { |
| 94 | + isa_builder.enable("has_avx512bitalg").unwrap(); |
| 95 | + } |
| 96 | + if std::is_x86_feature_detected!("avx512dq") { |
| 97 | + isa_builder.enable("has_avx512dq").unwrap(); |
| 98 | + } |
| 99 | + if std::is_x86_feature_detected!("avx512f") { |
| 100 | + isa_builder.enable("has_avx512f").unwrap(); |
| 101 | + } |
| 102 | + if std::is_x86_feature_detected!("avx512vl") { |
| 103 | + isa_builder.enable("has_avx512vl").unwrap(); |
| 104 | + } |
| 105 | + if std::is_x86_feature_detected!("avx512vbmi") { |
| 106 | + isa_builder.enable("has_avx512vbmi").unwrap(); |
| 107 | + } |
| 108 | + if std::is_x86_feature_detected!("lzcnt") { |
| 109 | + isa_builder.enable("has_lzcnt").unwrap(); |
| 110 | + } |
| 111 | + } |
| 112 | + |
| 113 | + #[cfg(target_arch = "aarch64")] |
| 114 | + { |
| 115 | + use cranelift_codegen::settings::Configurable; |
| 116 | + |
| 117 | + if !infer_native_flags { |
| 118 | + return Ok(isa_builder); |
| 119 | + } |
| 120 | + |
| 121 | + if std::arch::is_aarch64_feature_detected!("lse") { |
| 122 | + isa_builder.enable("has_lse").unwrap(); |
| 123 | + } |
| 124 | + |
| 125 | + if std::arch::is_aarch64_feature_detected!("paca") { |
| 126 | + isa_builder.enable("has_pauth").unwrap(); |
| 127 | + } |
| 128 | + |
| 129 | + if cfg!(target_os = "macos") { |
| 130 | + // Pointer authentication is always available on Apple Silicon. |
| 131 | + isa_builder.enable("sign_return_address").unwrap(); |
| 132 | + // macOS enforces the use of the B key for return addresses. |
| 133 | + isa_builder.enable("sign_return_address_with_bkey").unwrap(); |
| 134 | + } |
| 135 | + } |
| 136 | + |
| 137 | + // There is no is_s390x_feature_detected macro yet, so for now |
| 138 | + // we use getauxval from the libc crate directly. |
| 139 | + #[cfg(all(target_arch = "s390x", target_os = "linux"))] |
| 140 | + { |
| 141 | + use cranelift_codegen::settings::Configurable; |
| 142 | + |
| 143 | + if !infer_native_flags { |
| 144 | + return Ok(isa_builder); |
| 145 | + } |
| 146 | + |
| 147 | + let v = unsafe { libc::getauxval(libc::AT_HWCAP) }; |
| 148 | + const HWCAP_S390X_VXRS_EXT2: libc::c_ulong = 32768; |
| 149 | + if (v & HWCAP_S390X_VXRS_EXT2) != 0 { |
| 150 | + isa_builder.enable("has_vxrs_ext2").unwrap(); |
| 151 | + // There is no separate HWCAP bit for mie2, so assume |
| 152 | + // that any machine with vxrs_ext2 also has mie2. |
| 153 | + isa_builder.enable("has_mie2").unwrap(); |
| 154 | + } |
| 155 | + } |
| 156 | + |
| 157 | + // `is_riscv_feature_detected` is nightly only for now, use |
| 158 | + // getauxval from the libc crate directly as a temporary measure. |
| 159 | + #[cfg(all(target_arch = "riscv64", target_os = "linux"))] |
| 160 | + { |
| 161 | + use cranelift_codegen::settings::Configurable; |
| 162 | + |
| 163 | + if !infer_native_flags { |
| 164 | + return Ok(isa_builder); |
| 165 | + } |
| 166 | + |
| 167 | + let v = unsafe { libc::getauxval(libc::AT_HWCAP) }; |
| 168 | + |
| 169 | + const HWCAP_RISCV_EXT_A: libc::c_ulong = 1 << (b'a' - b'a'); |
| 170 | + const HWCAP_RISCV_EXT_C: libc::c_ulong = 1 << (b'c' - b'a'); |
| 171 | + const HWCAP_RISCV_EXT_D: libc::c_ulong = 1 << (b'd' - b'a'); |
| 172 | + const HWCAP_RISCV_EXT_F: libc::c_ulong = 1 << (b'f' - b'a'); |
| 173 | + const HWCAP_RISCV_EXT_M: libc::c_ulong = 1 << (b'm' - b'a'); |
| 174 | + const HWCAP_RISCV_EXT_V: libc::c_ulong = 1 << (b'v' - b'a'); |
| 175 | + |
| 176 | + if (v & HWCAP_RISCV_EXT_A) != 0 { |
| 177 | + isa_builder.enable("has_a").unwrap(); |
| 178 | + } |
| 179 | + |
| 180 | + if (v & HWCAP_RISCV_EXT_C) != 0 { |
| 181 | + isa_builder.enable("has_c").unwrap(); |
| 182 | + } |
| 183 | + |
| 184 | + if (v & HWCAP_RISCV_EXT_D) != 0 { |
| 185 | + isa_builder.enable("has_d").unwrap(); |
| 186 | + } |
| 187 | + |
| 188 | + if (v & HWCAP_RISCV_EXT_F) != 0 { |
| 189 | + isa_builder.enable("has_f").unwrap(); |
| 190 | + |
| 191 | + // TODO: There doesn't seem to be a bit associated with this extension |
| 192 | + // rust enables it with the `f` extension: |
| 193 | + // https://github.com/rust-lang/stdarch/blob/790411f93c4b5eada3c23abb4c9a063fb0b24d99/crates/std_detect/src/detect/os/linux/riscv.rs#L43 |
| 194 | + isa_builder.enable("has_zicsr").unwrap(); |
| 195 | + } |
| 196 | + |
| 197 | + if (v & HWCAP_RISCV_EXT_M) != 0 { |
| 198 | + isa_builder.enable("has_m").unwrap(); |
| 199 | + } |
| 200 | + |
| 201 | + if (v & HWCAP_RISCV_EXT_V) != 0 { |
| 202 | + isa_builder.enable("has_v").unwrap(); |
| 203 | + } |
| 204 | + |
| 205 | + // TODO: ZiFencei does not have a bit associated with it |
| 206 | + // TODO: Zbkb does not have a bit associated with it |
| 207 | + } |
| 208 | + |
| 209 | + // squelch warnings about unused mut/variables on some platforms. |
| 210 | + drop(&mut isa_builder); |
| 211 | + drop(infer_native_flags); |
| 212 | + |
| 213 | + Ok(isa_builder) |
| 214 | +} |
| 215 | + |
| 216 | +#[cfg(test)] |
| 217 | +mod tests { |
| 218 | + use super::builder; |
| 219 | + use cranelift_codegen::isa::CallConv; |
| 220 | + use cranelift_codegen::settings; |
| 221 | + |
| 222 | + #[test] |
| 223 | + fn test() { |
| 224 | + if let Ok(isa_builder) = builder() { |
| 225 | + let flag_builder = settings::builder(); |
| 226 | + let isa = isa_builder.finish(settings::Flags::new(flag_builder)).unwrap(); |
| 227 | + |
| 228 | + if cfg!(all(target_os = "macos", target_arch = "aarch64")) { |
| 229 | + assert_eq!(isa.default_call_conv(), CallConv::AppleAarch64); |
| 230 | + } else if cfg!(any(unix, target_os = "nebulet")) { |
| 231 | + assert_eq!(isa.default_call_conv(), CallConv::SystemV); |
| 232 | + } else if cfg!(windows) { |
| 233 | + assert_eq!(isa.default_call_conv(), CallConv::WindowsFastcall); |
| 234 | + } |
| 235 | + |
| 236 | + if cfg!(target_pointer_width = "64") { |
| 237 | + assert_eq!(isa.pointer_bits(), 64); |
| 238 | + } else if cfg!(target_pointer_width = "32") { |
| 239 | + assert_eq!(isa.pointer_bits(), 32); |
| 240 | + } else if cfg!(target_pointer_width = "16") { |
| 241 | + assert_eq!(isa.pointer_bits(), 16); |
| 242 | + } |
| 243 | + } |
| 244 | + } |
| 245 | +} |
| 246 | + |
| 247 | +/// Version number of this crate. |
| 248 | +pub const VERSION: &str = env!("CARGO_PKG_VERSION"); |
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