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 28macro_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 40define_panicking_intrinsics!("`f32` should not be used", { 41 __addsf3, 42 __eqsf2, 43 __gesf2, 44 __lesf2, 45 __ltsf2, 46 __mulsf3, 47 __nesf2, 48 __unordsf2, 49}); 50 51define_panicking_intrinsics!("`f64` should not be used", { 52 __adddf3, 53 __ledf2, 54 __ltdf2, 55 __muldf3, 56 __unorddf2, 57}); 58 59define_panicking_intrinsics!("`i128` should not be used", { 60 __ashrti3, 61 __muloti4, 62 __multi3, 63}); 64 65define_panicking_intrinsics!("`u128` should not be used", { 66 __ashlti3, 67 __lshrti3, 68 __udivmodti4, 69 __udivti3, 70 __umodti3, 71}); 72 73// NOTE: if you are adding a new intrinsic here, you should also add it to 74// `redirect-intrinsics` in `rust/Makefile`. 75