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 #![allow(internal_features)] 23 #![feature(compiler_builtins)] 24 #![compiler_builtins] 25 #![no_builtins] 26 #![no_std] 27 28 macro_rules! define_panicking_intrinsics( 29 ($reason: tt, { $($ident: ident, )* }) => { 30 $( 31 #[doc(hidden)] 32 #[export_name = concat!("__rust", stringify!($ident))] 33 pub extern "C" fn $ident() { 34 panic!($reason); 35 } 36 )* 37 } 38 ); 39 40 define_panicking_intrinsics!("`f32` should not be used", { 41 __addsf3, 42 __eqsf2, 43 __extendsfdf2, 44 __gesf2, 45 __lesf2, 46 __ltsf2, 47 __mulsf3, 48 __nesf2, 49 __truncdfsf2, 50 __unordsf2, 51 }); 52 53 define_panicking_intrinsics!("`f64` should not be used", { 54 __adddf3, 55 __eqdf2, 56 __ledf2, 57 __ltdf2, 58 __muldf3, 59 __unorddf2, 60 }); 61 62 define_panicking_intrinsics!("`i128` should not be used", { 63 __ashrti3, 64 __muloti4, 65 __multi3, 66 }); 67 68 define_panicking_intrinsics!("`u128` should not be used", { 69 __ashlti3, 70 __lshrti3, 71 __udivmodti4, 72 __udivti3, 73 __umodti3, 74 }); 75 76 // NOTE: if you are adding a new intrinsic here, you should also add it to 77 // `redirect-intrinsics` in `rust/Makefile`. 78