rustc_sanitizers/cfi/typeid/
mod.rs

1//! Type metadata identifiers for LLVM Control Flow Integrity (CFI) and cross-language LLVM CFI
2//! support for the Rust compiler.
3//!
4//! For more information about LLVM CFI and cross-language LLVM CFI support for the Rust compiler,
5//! see design document in the tracking issue #89653.
6
7use bitflags::bitflags;
8use rustc_middle::ty::{Instance, Ty, TyCtxt};
9use rustc_target::callconv::FnAbi;
10
11bitflags! {
12    /// Options for typeid_for_fnabi.
13    #[derive(Clone, Copy, Debug)]
14    pub struct TypeIdOptions: u32 {
15        /// Generalizes pointers for compatibility with Clang
16        /// `-fsanitize-cfi-icall-generalize-pointers` option for cross-language LLVM CFI and KCFI
17        /// support.
18        const GENERALIZE_POINTERS = 1;
19        /// Generalizes repr(C) user-defined type for extern function types with the "C" calling
20        /// convention (or extern types) for cross-language LLVM CFI and  KCFI support.
21        const GENERALIZE_REPR_C = 2;
22        /// Normalizes integers for compatibility with Clang
23        /// `-fsanitize-cfi-icall-experimental-normalize-integers` option for cross-language LLVM
24        /// CFI and  KCFI support.
25        const NORMALIZE_INTEGERS = 4;
26        /// Do not perform self type erasure for attaching a secondary type id to methods with their
27        /// concrete self so they can be used as function pointers.
28        ///
29        /// (This applies to typeid_for_instance only and should be used to attach a secondary type
30        /// id to methods during their declaration/definition so they match the type ids returned by
31        /// either typeid_for_instance or typeid_for_fnabi at call sites during code generation for
32        /// type membership tests when methods are used as function pointers.)
33        const USE_CONCRETE_SELF = 8;
34    }
35}
36
37pub mod itanium_cxx_abi;
38
39/// Returns a type metadata identifier for the specified FnAbi.
40pub fn typeid_for_fnabi<'tcx>(
41    tcx: TyCtxt<'tcx>,
42    fn_abi: &FnAbi<'tcx, Ty<'tcx>>,
43    options: TypeIdOptions,
44) -> String {
45    itanium_cxx_abi::typeid_for_fnabi(tcx, fn_abi, options)
46}
47
48/// Returns a type metadata identifier for the specified Instance.
49pub fn typeid_for_instance<'tcx>(
50    tcx: TyCtxt<'tcx>,
51    instance: Instance<'tcx>,
52    options: TypeIdOptions,
53) -> String {
54    itanium_cxx_abi::typeid_for_instance(tcx, instance, options)
55}