diff options
Diffstat (limited to 'compiler/rustc_codegen_cranelift/src/cranelift_native.rs')
-rw-r--r-- | compiler/rustc_codegen_cranelift/src/cranelift_native.rs | 248 |
1 files changed, 248 insertions, 0 deletions
diff --git a/compiler/rustc_codegen_cranelift/src/cranelift_native.rs b/compiler/rustc_codegen_cranelift/src/cranelift_native.rs new file mode 100644 index 000000000..6c4efca44 --- /dev/null +++ b/compiler/rustc_codegen_cranelift/src/cranelift_native.rs @@ -0,0 +1,248 @@ +// Vendored from https://github.com/bytecodealliance/wasmtime/blob/b58a197d33f044193c3d608010f5e6ec394ac07e/cranelift/native/src/lib.rs +// which is licensed as +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// unlike rustc_codegen_cranelift itself. Also applies a small change to remove #![cfg_attr] that +// rust's CI complains about and to fix formatting to match rustc. +// FIXME revert back to the external crate with Cranelift 0.93 +#![allow(warnings)] + +//! 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)] + +use cranelift_codegen::isa; +use target_lexicon::Triple; + +/// 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> { + builder_with_options(true) +} + +/// Return an `isa` builder configured for the current host +/// machine, or `Err(())` if the host machine is not supported +/// in the current configuration. +/// +/// Selects the given backend variant specifically; this is +/// useful when more than oen backend exists for a given target +/// (e.g., on x86-64). +pub fn builder_with_options(infer_native_flags: bool) -> 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", + })?; + + #[cfg(target_arch = "x86_64")] + { + use cranelift_codegen::settings::Configurable; + + if !std::is_x86_feature_detected!("sse2") { + return Err("x86 support requires SSE2"); + } + + if !infer_native_flags { + return Ok(isa_builder); + } + + // These are temporarily enabled by default (see #3810 for + // more) so that a default-constructed `Flags` can work with + // default Wasmtime features. Otherwise, the user must + // explicitly use native flags or turn these on when on x86-64 + // platforms to avoid a configuration panic. In order for the + // "enable if detected" logic below to work, we must turn them + // *off* (differing from the default) and then re-enable below + // if present. + isa_builder.set("has_sse3", "false").unwrap(); + isa_builder.set("has_ssse3", "false").unwrap(); + isa_builder.set("has_sse41", "false").unwrap(); + isa_builder.set("has_sse42", "false").unwrap(); + + if std::is_x86_feature_detected!("sse3") { + isa_builder.enable("has_sse3").unwrap(); + } + if std::is_x86_feature_detected!("ssse3") { + isa_builder.enable("has_ssse3").unwrap(); + } + if std::is_x86_feature_detected!("sse4.1") { + isa_builder.enable("has_sse41").unwrap(); + } + if std::is_x86_feature_detected!("sse4.2") { + isa_builder.enable("has_sse42").unwrap(); + } + if std::is_x86_feature_detected!("popcnt") { + isa_builder.enable("has_popcnt").unwrap(); + } + if std::is_x86_feature_detected!("avx") { + isa_builder.enable("has_avx").unwrap(); + } + if std::is_x86_feature_detected!("avx2") { + isa_builder.enable("has_avx2").unwrap(); + } + if std::is_x86_feature_detected!("fma") { + isa_builder.enable("has_fma").unwrap(); + } + if std::is_x86_feature_detected!("bmi1") { + isa_builder.enable("has_bmi1").unwrap(); + } + if std::is_x86_feature_detected!("bmi2") { + isa_builder.enable("has_bmi2").unwrap(); + } + if std::is_x86_feature_detected!("avx512bitalg") { + isa_builder.enable("has_avx512bitalg").unwrap(); + } + if std::is_x86_feature_detected!("avx512dq") { + isa_builder.enable("has_avx512dq").unwrap(); + } + if std::is_x86_feature_detected!("avx512f") { + isa_builder.enable("has_avx512f").unwrap(); + } + if std::is_x86_feature_detected!("avx512vl") { + isa_builder.enable("has_avx512vl").unwrap(); + } + if std::is_x86_feature_detected!("avx512vbmi") { + isa_builder.enable("has_avx512vbmi").unwrap(); + } + if std::is_x86_feature_detected!("lzcnt") { + isa_builder.enable("has_lzcnt").unwrap(); + } + } + + #[cfg(target_arch = "aarch64")] + { + use cranelift_codegen::settings::Configurable; + + if !infer_native_flags { + return Ok(isa_builder); + } + + if std::arch::is_aarch64_feature_detected!("lse") { + isa_builder.enable("has_lse").unwrap(); + } + + if std::arch::is_aarch64_feature_detected!("paca") { + isa_builder.enable("has_pauth").unwrap(); + } + + if cfg!(target_os = "macos") { + // Pointer authentication is always available on Apple Silicon. + isa_builder.enable("sign_return_address").unwrap(); + // macOS enforces the use of the B key for return addresses. + isa_builder.enable("sign_return_address_with_bkey").unwrap(); + } + } + + // There is no is_s390x_feature_detected macro yet, so for now + // we use getauxval from the libc crate directly. + #[cfg(all(target_arch = "s390x", target_os = "linux"))] + { + use cranelift_codegen::settings::Configurable; + + if !infer_native_flags { + return Ok(isa_builder); + } + + let v = unsafe { libc::getauxval(libc::AT_HWCAP) }; + const HWCAP_S390X_VXRS_EXT2: libc::c_ulong = 32768; + if (v & HWCAP_S390X_VXRS_EXT2) != 0 { + isa_builder.enable("has_vxrs_ext2").unwrap(); + // There is no separate HWCAP bit for mie2, so assume + // that any machine with vxrs_ext2 also has mie2. + isa_builder.enable("has_mie2").unwrap(); + } + } + + // `is_riscv_feature_detected` is nightly only for now, use + // getauxval from the libc crate directly as a temporary measure. + #[cfg(all(target_arch = "riscv64", target_os = "linux"))] + { + use cranelift_codegen::settings::Configurable; + + if !infer_native_flags { + return Ok(isa_builder); + } + + let v = unsafe { libc::getauxval(libc::AT_HWCAP) }; + + const HWCAP_RISCV_EXT_A: libc::c_ulong = 1 << (b'a' - b'a'); + const HWCAP_RISCV_EXT_C: libc::c_ulong = 1 << (b'c' - b'a'); + const HWCAP_RISCV_EXT_D: libc::c_ulong = 1 << (b'd' - b'a'); + const HWCAP_RISCV_EXT_F: libc::c_ulong = 1 << (b'f' - b'a'); + const HWCAP_RISCV_EXT_M: libc::c_ulong = 1 << (b'm' - b'a'); + const HWCAP_RISCV_EXT_V: libc::c_ulong = 1 << (b'v' - b'a'); + + if (v & HWCAP_RISCV_EXT_A) != 0 { + isa_builder.enable("has_a").unwrap(); + } + + if (v & HWCAP_RISCV_EXT_C) != 0 { + isa_builder.enable("has_c").unwrap(); + } + + if (v & HWCAP_RISCV_EXT_D) != 0 { + isa_builder.enable("has_d").unwrap(); + } + + if (v & HWCAP_RISCV_EXT_F) != 0 { + isa_builder.enable("has_f").unwrap(); + + // TODO: There doesn't seem to be a bit associated with this extension + // rust enables it with the `f` extension: + // https://github.com/rust-lang/stdarch/blob/790411f93c4b5eada3c23abb4c9a063fb0b24d99/crates/std_detect/src/detect/os/linux/riscv.rs#L43 + isa_builder.enable("has_zicsr").unwrap(); + } + + if (v & HWCAP_RISCV_EXT_M) != 0 { + isa_builder.enable("has_m").unwrap(); + } + + if (v & HWCAP_RISCV_EXT_V) != 0 { + isa_builder.enable("has_v").unwrap(); + } + + // TODO: ZiFencei does not have a bit associated with it + // TODO: Zbkb does not have a bit associated with it + } + + // squelch warnings about unused mut/variables on some platforms. + drop(&mut isa_builder); + drop(infer_native_flags); + + Ok(isa_builder) +} + +#[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)).unwrap(); + + if cfg!(all(target_os = "macos", target_arch = "aarch64")) { + assert_eq!(isa.default_call_conv(), CallConv::AppleAarch64); + } else 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); + } else if cfg!(target_pointer_width = "32") { + assert_eq!(isa.pointer_bits(), 32); + } else 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"); |