1 // SPDX-License-Identifier: GPL-2.0 2 3 //! Our own `compiler_builtins`. 4 //! 5 //! Rust provides [`compiler_builtins`] as a port of LLVM's [`compiler-rt`]. 6 //! Since we do not need the vast majority of them, we avoid the dependency 7 //! by providing this file. 8 //! 9 //! At the moment, some builtins are required that should not be. For instance, 10 //! [`core`] has 128-bit integers functionality which we should not be compiling 11 //! in. We will work with upstream [`core`] to provide feature flags to disable 12 //! the parts we do not need. For the moment, we define them to [`panic!`] at 13 //! runtime for simplicity to catch mistakes, instead of performing surgery 14 //! on `core.o`. 15 //! 16 //! In any case, all these symbols are weakened to ensure we do not override 17 //! those that may be provided by the rest of the kernel. 18 //! 19 //! [`compiler_builtins`]: https://github.com/rust-lang/compiler-builtins 20 //! [`compiler-rt`]: https://compiler-rt.llvm.org/ 21 22 #![feature(compiler_builtins)] 23 #![compiler_builtins] 24 #![no_builtins] 25 #![no_std] 26 27 macro_rules! define_panicking_intrinsics( 28 ($reason: tt, { $($ident: ident, )* }) => { 29 $( 30 #[doc(hidden)] 31 #[export_name = concat!("__rust", stringify!($ident))] 32 pub extern "C" fn $ident() { 33 panic!($reason); 34 } 35 )* 36 } 37 ); 38 39 define_panicking_intrinsics!("`f32` should not be used", { 40 __addsf3, 41 __eqsf2, 42 __gesf2, 43 __lesf2, 44 __ltsf2, 45 __mulsf3, 46 __nesf2, 47 __unordsf2, 48 }); 49 50 define_panicking_intrinsics!("`f64` should not be used", { 51 __adddf3, 52 __ledf2, 53 __ltdf2, 54 __muldf3, 55 __unorddf2, 56 }); 57 58 define_panicking_intrinsics!("`i128` should not be used", { 59 __ashrti3, 60 __muloti4, 61 __multi3, 62 }); 63 64 define_panicking_intrinsics!("`u128` should not be used", { 65 __ashlti3, 66 __lshrti3, 67 __udivmodti4, 68 __udivti3, 69 __umodti3, 70 }); 71 72 // NOTE: if you are adding a new intrinsic here, you should also add it to 73 // `redirect-intrinsics` in `rust/Makefile`. 74