From 698f8c2f01ea549d77d7dc3338a12e04c11057b9 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Wed, 17 Apr 2024 14:02:58 +0200 Subject: Adding upstream version 1.64.0+dfsg1. Signed-off-by: Daniel Baumann --- vendor/compiler_builtins/src/macros.rs | 448 +++++++++++++++++++++++++++++++++ 1 file changed, 448 insertions(+) create mode 100644 vendor/compiler_builtins/src/macros.rs (limited to 'vendor/compiler_builtins/src/macros.rs') diff --git a/vendor/compiler_builtins/src/macros.rs b/vendor/compiler_builtins/src/macros.rs new file mode 100644 index 000000000..518a18d4d --- /dev/null +++ b/vendor/compiler_builtins/src/macros.rs @@ -0,0 +1,448 @@ +//! Macros shared throughout the compiler-builtins implementation + +/// Changes the visibility to `pub` if feature "public-test-deps" is set +#[cfg(not(feature = "public-test-deps"))] +macro_rules! public_test_dep { + ($(#[$($meta:meta)*])* pub(crate) $ident:ident $($tokens:tt)*) => { + $(#[$($meta)*])* pub(crate) $ident $($tokens)* + }; +} + +/// Changes the visibility to `pub` if feature "public-test-deps" is set +#[cfg(feature = "public-test-deps")] +macro_rules! public_test_dep { + {$(#[$($meta:meta)*])* pub(crate) $ident:ident $($tokens:tt)*} => { + $(#[$($meta)*])* pub $ident $($tokens)* + }; +} + +/// The "main macro" used for defining intrinsics. +/// +/// The compiler-builtins library is super platform-specific with tons of crazy +/// little tweaks for various platforms. As a result it *could* involve a lot of +/// #[cfg] and macro soup, but the intention is that this macro alleviates a lot +/// of that complexity. Ideally this macro has all the weird ABI things +/// platforms need and elsewhere in this library it just looks like normal Rust +/// code. +/// +/// This macro is structured to be invoked with a bunch of functions that looks +/// like: +/// +/// intrinsics! { +/// pub extern "C" fn foo(a: i32) -> u32 { +/// // ... +/// } +/// +/// #[nonstandard_attribute] +/// pub extern "C" fn bar(a: i32) -> u32 { +/// // ... +/// } +/// } +/// +/// Each function is defined in a manner that looks like a normal Rust function. +/// The macro then accepts a few nonstandard attributes that can decorate +/// various functions. Each of the attributes is documented below with what it +/// can do, and each of them slightly tweaks how further expansion happens. +/// +/// A quick overview of attributes supported right now are: +/// +/// * `maybe_use_optimized_c_shim` - indicates that the Rust implementation is +/// ignored if an optimized C version was compiled. +/// * `aapcs_on_arm` - forces the ABI of the function to be `"aapcs"` on ARM and +/// the specified ABI everywhere else. +/// * `unadjusted_on_win64` - like `aapcs_on_arm` this switches to the +/// `"unadjusted"` abi on Win64 and the specified abi elsewhere. +/// * `win64_128bit_abi_hack` - this attribute is used for 128-bit integer +/// intrinsics where the ABI is slightly tweaked on Windows platforms, but +/// it's a normal ABI elsewhere for returning a 128 bit integer. +/// * `arm_aeabi_alias` - handles the "aliasing" of various intrinsics on ARM +/// their otherwise typical names to other prefixed ones. +/// +macro_rules! intrinsics { + () => (); + + // Support cfg_attr: + ( + #[cfg_attr($e:meta, $($attr:tt)*)] + $(#[$($attrs:tt)*])* + pub extern $abi:tt fn $name:ident( $($argname:ident: $ty:ty),* ) $(-> $ret:ty)? { + $($body:tt)* + } + $($rest:tt)* + ) => ( + #[cfg($e)] + intrinsics! { + #[$($attr)*] + $(#[$($attrs)*])* + pub extern $abi fn $name($($argname: $ty),*) $(-> $ret)? { + $($body)* + } + } + + #[cfg(not($e))] + intrinsics! { + $(#[$($attrs)*])* + pub extern $abi fn $name($($argname: $ty),*) $(-> $ret)? { + $($body)* + } + } + + intrinsics!($($rest)*); + ); + + // Right now there's a bunch of architecture-optimized intrinsics in the + // stock compiler-rt implementation. Not all of these have been ported over + // to Rust yet so when the `c` feature of this crate is enabled we fall back + // to the architecture-specific versions which should be more optimized. The + // purpose of this macro is to easily allow specifying this. + // + // The `#[maybe_use_optimized_c_shim]` attribute indicates that this + // intrinsic may have an optimized C version. In these situations the build + // script, if the C code is enabled and compiled, will emit a cfg directive + // to get passed to rustc for our compilation. If that cfg is set we skip + // the Rust implementation, but if the attribute is not enabled then we + // compile in the Rust implementation. + ( + #[maybe_use_optimized_c_shim] + $(#[$($attr:tt)*])* + pub extern $abi:tt fn $name:ident( $($argname:ident: $ty:ty),* ) $(-> $ret:ty)? { + $($body:tt)* + } + + $($rest:tt)* + ) => ( + #[cfg($name = "optimized-c")] + pub extern $abi fn $name( $($argname: $ty),* ) $(-> $ret)? { + extern $abi { + fn $name($($argname: $ty),*) $(-> $ret)?; + } + unsafe { + $name($($argname),*) + } + } + + #[cfg(not($name = "optimized-c"))] + intrinsics! { + $(#[$($attr)*])* + pub extern $abi fn $name( $($argname: $ty),* ) $(-> $ret)? { + $($body)* + } + } + + intrinsics!($($rest)*); + ); + + // We recognize the `#[aapcs_on_arm]` attribute here and generate the + // same intrinsic but force it to have the `"aapcs"` calling convention on + // ARM and `"C"` elsewhere. + ( + #[aapcs_on_arm] + $(#[$($attr:tt)*])* + pub extern $abi:tt fn $name:ident( $($argname:ident: $ty:ty),* ) $(-> $ret:ty)? { + $($body:tt)* + } + + $($rest:tt)* + ) => ( + #[cfg(target_arch = "arm")] + intrinsics! { + $(#[$($attr)*])* + pub extern "aapcs" fn $name( $($argname: $ty),* ) $(-> $ret)? { + $($body)* + } + } + + #[cfg(not(target_arch = "arm"))] + intrinsics! { + $(#[$($attr)*])* + pub extern $abi fn $name( $($argname: $ty),* ) $(-> $ret)? { + $($body)* + } + } + + intrinsics!($($rest)*); + ); + + // Like aapcs above we recognize an attribute for the "unadjusted" abi on + // win64 for some methods. + ( + #[unadjusted_on_win64] + $(#[$($attr:tt)*])* + pub extern $abi:tt fn $name:ident( $($argname:ident: $ty:ty),* ) $(-> $ret:ty)? { + $($body:tt)* + } + + $($rest:tt)* + ) => ( + #[cfg(all(windows, target_pointer_width = "64"))] + intrinsics! { + $(#[$($attr)*])* + pub extern "unadjusted" fn $name( $($argname: $ty),* ) $(-> $ret)? { + $($body)* + } + } + + #[cfg(not(all(windows, target_pointer_width = "64")))] + intrinsics! { + $(#[$($attr)*])* + pub extern $abi fn $name( $($argname: $ty),* ) $(-> $ret)? { + $($body)* + } + } + + intrinsics!($($rest)*); + ); + + // Some intrinsics on win64 which return a 128-bit integer have an.. unusual + // calling convention. That's managed here with this "abi hack" which alters + // the generated symbol's ABI. + // + // This will still define a function in this crate with the given name and + // signature, but the actual symbol for the intrinsic may have a slightly + // different ABI on win64. + ( + #[win64_128bit_abi_hack] + $(#[$($attr:tt)*])* + pub extern $abi:tt fn $name:ident( $($argname:ident: $ty:ty),* ) $(-> $ret:ty)? { + $($body:tt)* + } + + $($rest:tt)* + ) => ( + #[cfg(all(windows, target_arch = "x86_64"))] + $(#[$($attr)*])* + pub extern $abi fn $name( $($argname: $ty),* ) $(-> $ret)? { + $($body)* + } + + #[cfg(all(windows, target_arch = "x86_64"))] + pub mod $name { + #[cfg_attr(not(feature = "mangled-names"), no_mangle)] + pub extern $abi fn $name( $($argname: $ty),* ) + -> ::macros::win64_128bit_abi_hack::U64x2 + { + let e: $($ret)? = super::$name($($argname),*); + ::macros::win64_128bit_abi_hack::U64x2::from(e) + } + } + + #[cfg(not(all(windows, target_arch = "x86_64")))] + intrinsics! { + $(#[$($attr)*])* + pub extern $abi fn $name( $($argname: $ty),* ) $(-> $ret)? { + $($body)* + } + } + + intrinsics!($($rest)*); + ); + + // A bunch of intrinsics on ARM are aliased in the standard compiler-rt + // build under `__aeabi_*` aliases, and LLVM will call these instead of the + // original function. The aliasing here is used to generate these symbols in + // the object file. + ( + #[arm_aeabi_alias = $alias:ident] + $(#[$($attr:tt)*])* + pub extern $abi:tt fn $name:ident( $($argname:ident: $ty:ty),* ) $(-> $ret:ty)? { + $($body:tt)* + } + + $($rest:tt)* + ) => ( + #[cfg(target_arch = "arm")] + pub extern $abi fn $name( $($argname: $ty),* ) $(-> $ret)? { + $($body)* + } + + #[cfg(target_arch = "arm")] + pub mod $name { + #[cfg_attr(not(feature = "mangled-names"), no_mangle)] + pub extern $abi fn $name( $($argname: $ty),* ) $(-> $ret)? { + super::$name($($argname),*) + } + } + + #[cfg(target_arch = "arm")] + pub mod $alias { + #[cfg_attr(not(feature = "mangled-names"), no_mangle)] + pub extern "aapcs" fn $alias( $($argname: $ty),* ) $(-> $ret)? { + super::$name($($argname),*) + } + } + + #[cfg(not(target_arch = "arm"))] + intrinsics! { + $(#[$($attr)*])* + pub extern $abi fn $name( $($argname: $ty),* ) $(-> $ret)? { + $($body)* + } + } + + intrinsics!($($rest)*); + ); + + // C mem* functions are only generated when the "mem" feature is enabled. + ( + #[mem_builtin] + $(#[$($attr:tt)*])* + pub unsafe extern $abi:tt fn $name:ident( $($argname:ident: $ty:ty),* ) $(-> $ret:ty)? { + $($body:tt)* + } + + $($rest:tt)* + ) => ( + $(#[$($attr)*])* + pub unsafe extern $abi fn $name( $($argname: $ty),* ) $(-> $ret)? { + $($body)* + } + + #[cfg(feature = "mem")] + pub mod $name { + $(#[$($attr)*])* + #[cfg_attr(not(feature = "mangled-names"), no_mangle)] + pub unsafe extern $abi fn $name( $($argname: $ty),* ) $(-> $ret)? { + super::$name($($argname),*) + } + } + + intrinsics!($($rest)*); + ); + + // Naked functions are special: we can't generate wrappers for them since + // they use a custom calling convention. + ( + #[naked] + $(#[$($attr:tt)*])* + pub unsafe extern $abi:tt fn $name:ident( $($argname:ident: $ty:ty),* ) $(-> $ret:ty)? { + $($body:tt)* + } + + $($rest:tt)* + ) => ( + pub mod $name { + #[naked] + $(#[$($attr)*])* + #[cfg_attr(not(feature = "mangled-names"), no_mangle)] + pub unsafe extern $abi fn $name( $($argname: $ty),* ) $(-> $ret)? { + $($body)* + } + } + + intrinsics!($($rest)*); + ); + + // For division and modulo, AVR uses a custom calling convention¹ that does + // not match our definitions here. Ideally we would just use hand-written + // naked functions, but that's quite a lot of code to port² - so for the + // time being we are just ignoring the problematic functions, letting + // avr-gcc (which is required to compile to AVR anyway) link them from + // libgcc. + // + // ¹ https://gcc.gnu.org/wiki/avr-gcc (see "Exceptions to the Calling + // Convention") + // ² https://github.com/gcc-mirror/gcc/blob/31048012db98f5ec9c2ba537bfd850374bdd771f/libgcc/config/avr/lib1funcs.S + ( + #[avr_skip] + $(#[$($attr:tt)*])* + pub extern $abi:tt fn $name:ident( $($argname:ident: $ty:ty),* ) $(-> $ret:ty)? { + $($body:tt)* + } + + $($rest:tt)* + ) => ( + #[cfg(not(target_arch = "avr"))] + intrinsics! { + $(#[$($attr)*])* + pub extern $abi fn $name( $($argname: $ty),* ) $(-> $ret)? { + $($body)* + } + } + + intrinsics!($($rest)*); + ); + + // This is the final catch-all rule. At this point we generate an + // intrinsic with a conditional `#[no_mangle]` directive to avoid + // interfering with duplicate symbols and whatnot during testing. + // + // The implementation is placed in a separate module, to take advantage + // of the fact that rustc partitions functions into code generation + // units based on module they are defined in. As a result we will have + // a separate object file for each intrinsic. For further details see + // corresponding PR in rustc https://github.com/rust-lang/rust/pull/70846 + // + // After the intrinsic is defined we just continue with the rest of the + // input we were given. + ( + $(#[$($attr:tt)*])* + pub extern $abi:tt fn $name:ident( $($argname:ident: $ty:ty),* ) $(-> $ret:ty)? { + $($body:tt)* + } + + $($rest:tt)* + ) => ( + $(#[$($attr)*])* + pub extern $abi fn $name( $($argname: $ty),* ) $(-> $ret)? { + $($body)* + } + + pub mod $name { + $(#[$($attr)*])* + #[cfg_attr(not(feature = "mangled-names"), no_mangle)] + pub extern $abi fn $name( $($argname: $ty),* ) $(-> $ret)? { + super::$name($($argname),*) + } + } + + intrinsics!($($rest)*); + ); + + // Same as the above for unsafe functions. + ( + $(#[$($attr:tt)*])* + pub unsafe extern $abi:tt fn $name:ident( $($argname:ident: $ty:ty),* ) $(-> $ret:ty)? { + $($body:tt)* + } + + $($rest:tt)* + ) => ( + $(#[$($attr)*])* + pub unsafe extern $abi fn $name( $($argname: $ty),* ) $(-> $ret)? { + $($body)* + } + + pub mod $name { + $(#[$($attr)*])* + #[cfg_attr(not(feature = "mangled-names"), no_mangle)] + pub unsafe extern $abi fn $name( $($argname: $ty),* ) $(-> $ret)? { + super::$name($($argname),*) + } + } + + intrinsics!($($rest)*); + ); +} + +// Hack for LLVM expectations for ABI on windows. This is used by the +// `#[win64_128bit_abi_hack]` attribute recognized above +#[cfg(all(windows, target_pointer_width = "64"))] +pub mod win64_128bit_abi_hack { + #[repr(simd)] + pub struct U64x2(u64, u64); + + impl From for U64x2 { + fn from(i: i128) -> U64x2 { + use int::DInt; + let j = i as u128; + U64x2(j.lo(), j.hi()) + } + } + + impl From for U64x2 { + fn from(i: u128) -> U64x2 { + use int::DInt; + U64x2(i.lo(), i.hi()) + } + } +} -- cgit v1.2.3