diff options
Diffstat (limited to 'vendor/compiler_builtins/src/macros.rs')
| -rw-r--r-- | vendor/compiler_builtins/src/macros.rs | 110 |
1 files changed, 108 insertions, 2 deletions
diff --git a/vendor/compiler_builtins/src/macros.rs b/vendor/compiler_builtins/src/macros.rs index 477c25684..59f25317e 100644 --- a/vendor/compiler_builtins/src/macros.rs +++ b/vendor/compiler_builtins/src/macros.rs @@ -25,6 +25,12 @@ macro_rules! public_test_dep { /// platforms need and elsewhere in this library it just looks like normal Rust /// code. /// +/// When the weak-intrinsics feature is enabled, all intrinsics functions are +/// marked with #[linkage = "weak"] so that they can be replaced by another +/// implementation at link time. This is particularly useful for mixed Rust/C++ +/// binaries that want to use the C++ intrinsics, otherwise linking against the +/// Rust stdlib will replace those from the compiler-rt library. +/// /// This macro is structured to be invoked with a bunch of functions that looks /// like: /// @@ -46,6 +52,10 @@ macro_rules! public_test_dep { /// /// A quick overview of attributes supported right now are: /// +/// * `weak` - indicates that the function should always be given weak linkage. +/// This attribute must come before other attributes, as the other attributes +/// will generate the final output function and need to have `weak` modify +/// them. /// * `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 @@ -57,7 +67,6 @@ macro_rules! public_test_dep { /// 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 { () => (); @@ -89,6 +98,95 @@ macro_rules! intrinsics { intrinsics!($($rest)*); ); + // Same as above but for unsafe. + ( + #[cfg_attr($e:meta, $($attr:tt)*)] + $(#[$($attrs:tt)*])* + pub unsafe extern $abi:tt fn $name:ident( $($argname:ident: $ty:ty),* ) $(-> $ret:ty)? { + $($body:tt)* + } + $($rest:tt)* + ) => ( + #[cfg($e)] + intrinsics! { + #[$($attr)*] + $(#[$($attrs)*])* + pub unsafe extern $abi fn $name($($argname: $ty),*) $(-> $ret)? { + $($body)* + } + } + + #[cfg(not($e))] + intrinsics! { + $(#[$($attrs)*])* + pub unsafe extern $abi fn $name($($argname: $ty),*) $(-> $ret)? { + $($body)* + } + } + + intrinsics!($($rest)*); + ); + + // Explicit weak linkage gets dropped when weak-intrinsics is on since it + // will be added unconditionally to all intrinsics and would conflict + // otherwise. + ( + #[weak] + $(#[$($attr:tt)*])* + pub extern $abi:tt fn $name:ident( $($argname:ident: $ty:ty),* ) $(-> $ret:ty)? { + $($body:tt)* + } + + $($rest:tt)* + ) => ( + #[cfg(feature = "weak-intrinsics")] + intrinsics! { + $(#[$($attr)*])* + pub extern $abi fn $name( $($argname: $ty),* ) $(-> $ret)? { + $($body)* + } + } + + #[cfg(not(feature = "weak-intrinsics"))] + intrinsics! { + $(#[$($attr)*])* + #[linkage = "weak"] + pub extern $abi fn $name( $($argname: $ty),* ) $(-> $ret)? { + $($body)* + } + } + + intrinsics!($($rest)*); + ); + // Same as above but for unsafe. + ( + #[weak] + $(#[$($attr:tt)*])* + pub unsafe extern $abi:tt fn $name:ident( $($argname:ident: $ty:ty),* ) $(-> $ret:ty)? { + $($body:tt)* + } + + $($rest:tt)* + ) => ( + #[cfg(feature = "weak-intrinsics")] + intrinsics! { + $(#[$($attr)*])* + pub unsafe extern $abi fn $name( $($argname: $ty),* ) $(-> $ret)? { + $($body)* + } + } + + #[cfg(not(feature = "weak-intrinsics"))] + intrinsics! { + $(#[$($attr)*])* + #[linkage = "weak"] + pub unsafe 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 @@ -112,6 +210,7 @@ macro_rules! intrinsics { $($rest:tt)* ) => ( #[cfg($name = "optimized-c")] + #[cfg_attr(feature = "weak-intrinsics", linkage = "weak")] pub extern $abi fn $name( $($argname: $ty),* ) $(-> $ret)? { extern $abi { fn $name($($argname: $ty),*) $(-> $ret)?; @@ -211,6 +310,7 @@ macro_rules! intrinsics { ) => ( #[cfg(all(any(windows, target_os = "uefi"), target_arch = "x86_64"))] $(#[$($attr)*])* + #[cfg_attr(feature = "weak-intrinsics", linkage = "weak")] pub extern $abi fn $name( $($argname: $ty),* ) $(-> $ret)? { $($body)* } @@ -218,6 +318,7 @@ macro_rules! intrinsics { #[cfg(all(any(windows, target_os = "uefi"), target_arch = "x86_64"))] pub mod $name { #[cfg_attr(not(feature = "mangled-names"), no_mangle)] + #[cfg_attr(feature = "weak-intrinsics", linkage = "weak")] pub extern $abi fn $name( $($argname: $ty),* ) -> ::macros::win64_128bit_abi_hack::U64x2 { @@ -258,6 +359,7 @@ macro_rules! intrinsics { #[cfg(target_arch = "arm")] pub mod $name { #[cfg_attr(not(feature = "mangled-names"), no_mangle)] + #[cfg_attr(feature = "weak-intrinsics", linkage = "weak")] pub extern $abi fn $name( $($argname: $ty),* ) $(-> $ret)? { super::$name($($argname),*) } @@ -266,7 +368,7 @@ macro_rules! intrinsics { #[cfg(target_arch = "arm")] pub mod $alias { #[cfg_attr(not(feature = "mangled-names"), no_mangle)] - #[cfg_attr(all(not(windows), not(target_vendor="apple")), linkage = "weak")] + #[cfg_attr(any(all(not(windows), not(target_vendor="apple"), feature = "weak-intrinsics")), linkage = "weak")] pub extern "aapcs" fn $alias( $($argname: $ty),* ) $(-> $ret)? { super::$name($($argname),*) } @@ -302,6 +404,7 @@ macro_rules! intrinsics { pub mod $name { $(#[$($attr)*])* #[cfg_attr(not(feature = "mangled-names"), no_mangle)] + #[cfg_attr(feature = "weak-intrinsics", linkage = "weak")] pub unsafe extern $abi fn $name( $($argname: $ty),* ) $(-> $ret)? { super::$name($($argname),*) } @@ -325,6 +428,7 @@ macro_rules! intrinsics { #[naked] $(#[$($attr)*])* #[cfg_attr(not(feature = "mangled-names"), no_mangle)] + #[cfg_attr(feature = "weak-intrinsics", linkage = "weak")] pub unsafe extern $abi fn $name( $($argname: $ty),* ) $(-> $ret)? { $($body)* } @@ -391,6 +495,7 @@ macro_rules! intrinsics { pub mod $name { $(#[$($attr)*])* #[cfg_attr(not(feature = "mangled-names"), no_mangle)] + #[cfg_attr(feature = "weak-intrinsics", linkage = "weak")] pub extern $abi fn $name( $($argname: $ty),* ) $(-> $ret)? { super::$name($($argname),*) } @@ -416,6 +521,7 @@ macro_rules! intrinsics { pub mod $name { $(#[$($attr)*])* #[cfg_attr(not(feature = "mangled-names"), no_mangle)] + #[cfg_attr(feature = "weak-intrinsics", linkage = "weak")] pub unsafe extern $abi fn $name( $($argname: $ty),* ) $(-> $ret)? { super::$name($($argname),*) } |