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Diffstat (limited to 'compiler/rustc_target/src/spec/abi/mod.rs')
| -rw-r--r-- | compiler/rustc_target/src/spec/abi/mod.rs | 341 |
1 files changed, 341 insertions, 0 deletions
diff --git a/compiler/rustc_target/src/spec/abi/mod.rs b/compiler/rustc_target/src/spec/abi/mod.rs new file mode 100644 index 00000000000..4c1f0c01a04 --- /dev/null +++ b/compiler/rustc_target/src/spec/abi/mod.rs @@ -0,0 +1,341 @@ +use std::fmt; + +use rustc_macros::HashStable_Generic; +use rustc_span::symbol::sym; +use rustc_span::{Span, Symbol}; + +#[cfg(test)] +mod tests; + +#[derive(PartialEq, Eq, PartialOrd, Ord, Hash, Clone, Copy, Debug)] +#[derive(HashStable_Generic, Encodable, Decodable)] +pub enum Abi { + // Some of the ABIs come first because every time we add a new ABI, we have to re-bless all the + // hashing tests. These are used in many places, so giving them stable values reduces test + // churn. The specific values are meaningless. + Rust, + C { + unwind: bool, + }, + Cdecl { + unwind: bool, + }, + Stdcall { + unwind: bool, + }, + Fastcall { + unwind: bool, + }, + Vectorcall { + unwind: bool, + }, + Thiscall { + unwind: bool, + }, + Aapcs { + unwind: bool, + }, + Win64 { + unwind: bool, + }, + SysV64 { + unwind: bool, + }, + PtxKernel, + Msp430Interrupt, + X86Interrupt, + AmdGpuKernel, + EfiApi, + AvrInterrupt, + AvrNonBlockingInterrupt, + CCmseNonSecureCall, + Wasm, + System { + unwind: bool, + }, + RustIntrinsic, + RustCall, + PlatformIntrinsic, + Unadjusted, + /// For things unlikely to be called, where reducing register pressure in + /// `extern "Rust"` callers is worth paying extra cost in the callee. + /// Stronger than just `#[cold]` because `fn` pointers might be incompatible. + RustCold, + RiscvInterruptM, + RiscvInterruptS, +} + +impl Abi { + pub fn supports_varargs(self) -> bool { + // * C and Cdecl obviously support varargs. + // * C can be based on Aapcs, SysV64 or Win64, so they must support varargs. + // * EfiApi is based on Win64 or C, so it also supports it. + // + // * Stdcall does not, because it would be impossible for the callee to clean + // up the arguments. (callee doesn't know how many arguments are there) + // * Same for Fastcall, Vectorcall and Thiscall. + // * System can become Stdcall, so is also a no-no. + // * Other calling conventions are related to hardware or the compiler itself. + match self { + Self::C { .. } + | Self::Cdecl { .. } + | Self::Aapcs { .. } + | Self::Win64 { .. } + | Self::SysV64 { .. } + | Self::EfiApi => true, + _ => false, + } + } +} + +#[derive(Copy, Clone)] +pub struct AbiData { + abi: Abi, + + /// Name of this ABI as we like it called. + name: &'static str, +} + +#[allow(non_upper_case_globals)] +const AbiDatas: &[AbiData] = &[ + AbiData { abi: Abi::Rust, name: "Rust" }, + AbiData { abi: Abi::C { unwind: false }, name: "C" }, + AbiData { abi: Abi::C { unwind: true }, name: "C-unwind" }, + AbiData { abi: Abi::Cdecl { unwind: false }, name: "cdecl" }, + AbiData { abi: Abi::Cdecl { unwind: true }, name: "cdecl-unwind" }, + AbiData { abi: Abi::Stdcall { unwind: false }, name: "stdcall" }, + AbiData { abi: Abi::Stdcall { unwind: true }, name: "stdcall-unwind" }, + AbiData { abi: Abi::Fastcall { unwind: false }, name: "fastcall" }, + AbiData { abi: Abi::Fastcall { unwind: true }, name: "fastcall-unwind" }, + AbiData { abi: Abi::Vectorcall { unwind: false }, name: "vectorcall" }, + AbiData { abi: Abi::Vectorcall { unwind: true }, name: "vectorcall-unwind" }, + AbiData { abi: Abi::Thiscall { unwind: false }, name: "thiscall" }, + AbiData { abi: Abi::Thiscall { unwind: true }, name: "thiscall-unwind" }, + AbiData { abi: Abi::Aapcs { unwind: false }, name: "aapcs" }, + AbiData { abi: Abi::Aapcs { unwind: true }, name: "aapcs-unwind" }, + AbiData { abi: Abi::Win64 { unwind: false }, name: "win64" }, + AbiData { abi: Abi::Win64 { unwind: true }, name: "win64-unwind" }, + AbiData { abi: Abi::SysV64 { unwind: false }, name: "sysv64" }, + AbiData { abi: Abi::SysV64 { unwind: true }, name: "sysv64-unwind" }, + AbiData { abi: Abi::PtxKernel, name: "ptx-kernel" }, + AbiData { abi: Abi::Msp430Interrupt, name: "msp430-interrupt" }, + AbiData { abi: Abi::X86Interrupt, name: "x86-interrupt" }, + AbiData { abi: Abi::AmdGpuKernel, name: "amdgpu-kernel" }, + AbiData { abi: Abi::EfiApi, name: "efiapi" }, + AbiData { abi: Abi::AvrInterrupt, name: "avr-interrupt" }, + AbiData { abi: Abi::AvrNonBlockingInterrupt, name: "avr-non-blocking-interrupt" }, + AbiData { abi: Abi::CCmseNonSecureCall, name: "C-cmse-nonsecure-call" }, + AbiData { abi: Abi::Wasm, name: "wasm" }, + AbiData { abi: Abi::System { unwind: false }, name: "system" }, + AbiData { abi: Abi::System { unwind: true }, name: "system-unwind" }, + AbiData { abi: Abi::RustIntrinsic, name: "rust-intrinsic" }, + AbiData { abi: Abi::RustCall, name: "rust-call" }, + AbiData { abi: Abi::PlatformIntrinsic, name: "platform-intrinsic" }, + AbiData { abi: Abi::Unadjusted, name: "unadjusted" }, + AbiData { abi: Abi::RustCold, name: "rust-cold" }, + AbiData { abi: Abi::RiscvInterruptM, name: "riscv-interrupt-m" }, + AbiData { abi: Abi::RiscvInterruptS, name: "riscv-interrupt-s" }, +]; + +#[derive(Copy, Clone, Debug)] +pub enum AbiUnsupported { + Unrecognized, + Reason { explain: &'static str }, +} + +/// Returns the ABI with the given name (if any). +pub fn lookup(name: &str) -> Result<Abi, AbiUnsupported> { + AbiDatas.iter().find(|abi_data| name == abi_data.name).map(|&x| x.abi).ok_or_else(|| match name { + "riscv-interrupt" => AbiUnsupported::Reason { + explain: "please use one of riscv-interrupt-m or riscv-interrupt-s for machine- or supervisor-level interrupts, respectively", + }, + "riscv-interrupt-u" => AbiUnsupported::Reason { + explain: "user-mode interrupt handlers have been removed from LLVM pending standardization, see: https://reviews.llvm.org/D149314", + }, + + _ => AbiUnsupported::Unrecognized, + + }) +} + +pub fn all_names() -> Vec<&'static str> { + AbiDatas.iter().map(|d| d.name).collect() +} + +pub fn enabled_names(features: &rustc_feature::Features, span: Span) -> Vec<&'static str> { + AbiDatas + .iter() + .map(|d| d.name) + .filter(|name| is_enabled(features, span, name).is_ok()) + .collect() +} + +pub enum AbiDisabled { + Unstable { feature: Symbol, explain: &'static str }, + Unrecognized, +} + +pub fn is_enabled( + features: &rustc_feature::Features, + span: Span, + name: &str, +) -> Result<(), AbiDisabled> { + let s = is_stable(name); + if let Err(AbiDisabled::Unstable { feature, .. }) = s { + if features.active(feature) || span.allows_unstable(feature) { + return Ok(()); + } + } + s +} + +pub fn is_stable(name: &str) -> Result<(), AbiDisabled> { + match name { + // Stable + "Rust" | "C" | "C-unwind" | "cdecl" | "cdecl-unwind" | "stdcall" | "stdcall-unwind" + | "fastcall" | "fastcall-unwind" | "aapcs" | "aapcs-unwind" | "win64" | "win64-unwind" + | "sysv64" | "sysv64-unwind" | "system" | "system-unwind" | "efiapi" | "thiscall" + | "thiscall-unwind" => Ok(()), + "rust-intrinsic" => Err(AbiDisabled::Unstable { + feature: sym::intrinsics, + explain: "intrinsics are subject to change", + }), + "platform-intrinsic" => Err(AbiDisabled::Unstable { + feature: sym::platform_intrinsics, + explain: "platform intrinsics are experimental and possibly buggy", + }), + "vectorcall" => Err(AbiDisabled::Unstable { + feature: sym::abi_vectorcall, + explain: "vectorcall is experimental and subject to change", + }), + "vectorcall-unwind" => Err(AbiDisabled::Unstable { + feature: sym::abi_vectorcall, + explain: "vectorcall-unwind ABI is experimental and subject to change", + }), + "rust-call" => Err(AbiDisabled::Unstable { + feature: sym::unboxed_closures, + explain: "rust-call ABI is subject to change", + }), + "rust-cold" => Err(AbiDisabled::Unstable { + feature: sym::rust_cold_cc, + explain: "rust-cold is experimental and subject to change", + }), + "ptx-kernel" => Err(AbiDisabled::Unstable { + feature: sym::abi_ptx, + explain: "PTX ABIs are experimental and subject to change", + }), + "unadjusted" => Err(AbiDisabled::Unstable { + feature: sym::abi_unadjusted, + explain: "unadjusted ABI is an implementation detail and perma-unstable", + }), + "msp430-interrupt" => Err(AbiDisabled::Unstable { + feature: sym::abi_msp430_interrupt, + explain: "msp430-interrupt ABI is experimental and subject to change", + }), + "x86-interrupt" => Err(AbiDisabled::Unstable { + feature: sym::abi_x86_interrupt, + explain: "x86-interrupt ABI is experimental and subject to change", + }), + "amdgpu-kernel" => Err(AbiDisabled::Unstable { + feature: sym::abi_amdgpu_kernel, + explain: "amdgpu-kernel ABI is experimental and subject to change", + }), + "avr-interrupt" | "avr-non-blocking-interrupt" => Err(AbiDisabled::Unstable { + feature: sym::abi_avr_interrupt, + explain: "avr-interrupt and avr-non-blocking-interrupt ABIs are experimental and subject to change", + }), + "riscv-interrupt-m" | "riscv-interrupt-s" => Err(AbiDisabled::Unstable { + feature: sym::abi_riscv_interrupt, + explain: "riscv-interrupt ABIs are experimental and subject to change", + }), + "C-cmse-nonsecure-call" => Err(AbiDisabled::Unstable { + feature: sym::abi_c_cmse_nonsecure_call, + explain: "C-cmse-nonsecure-call ABI is experimental and subject to change", + }), + "wasm" => Err(AbiDisabled::Unstable { + feature: sym::wasm_abi, + explain: "wasm ABI is experimental and subject to change", + }), + _ => Err(AbiDisabled::Unrecognized), + } +} + +impl Abi { + /// Default ABI chosen for `extern fn` declarations without an explicit ABI. + pub const FALLBACK: Abi = Abi::C { unwind: false }; + + #[inline] + pub fn index(self) -> usize { + // N.B., this ordering MUST match the AbiDatas array above. + // (This is ensured by the test indices_are_correct().) + use Abi::*; + let i = match self { + // Cross-platform ABIs + Rust => 0, + C { unwind: false } => 1, + C { unwind: true } => 2, + // Platform-specific ABIs + Cdecl { unwind: false } => 3, + Cdecl { unwind: true } => 4, + Stdcall { unwind: false } => 5, + Stdcall { unwind: true } => 6, + Fastcall { unwind: false } => 7, + Fastcall { unwind: true } => 8, + Vectorcall { unwind: false } => 9, + Vectorcall { unwind: true } => 10, + Thiscall { unwind: false } => 11, + Thiscall { unwind: true } => 12, + Aapcs { unwind: false } => 13, + Aapcs { unwind: true } => 14, + Win64 { unwind: false } => 15, + Win64 { unwind: true } => 16, + SysV64 { unwind: false } => 17, + SysV64 { unwind: true } => 18, + PtxKernel => 19, + Msp430Interrupt => 20, + X86Interrupt => 21, + AmdGpuKernel => 22, + EfiApi => 23, + AvrInterrupt => 24, + AvrNonBlockingInterrupt => 25, + CCmseNonSecureCall => 26, + Wasm => 27, + // Cross-platform ABIs + System { unwind: false } => 28, + System { unwind: true } => 29, + RustIntrinsic => 30, + RustCall => 31, + PlatformIntrinsic => 32, + Unadjusted => 33, + RustCold => 34, + RiscvInterruptM => 35, + RiscvInterruptS => 36, + }; + debug_assert!( + AbiDatas + .iter() + .enumerate() + .find(|(_, AbiData { abi, .. })| *abi == self) + .map(|(index, _)| index) + .expect("abi variant has associated data") + == i, + "Abi index did not match `AbiDatas` ordering" + ); + i + } + + #[inline] + pub fn data(self) -> &'static AbiData { + &AbiDatas[self.index()] + } + + pub fn name(self) -> &'static str { + self.data().name + } +} + +impl fmt::Display for Abi { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + write!(f, "\"{}\"", self.name()) + } +} |