Skip to content

Commit

Permalink
CFI: Monomorphize transparent ADTs before typeid
Browse files Browse the repository at this point in the history
Monomorphise `#[repr(transparent)]` parameterized ADTs before turning
them into an Itanium mangled String.

`#[repr(transparent)]` ADTs currently use the single field to represent
them in their CFI type ID to ensure that they are compatible. However,
if that type involves a type parameter instantiated at the ADT level, as
in `ManuallyDrop`, this will currently ICE as the `Parameter` type
cannot be mangled. Since this happens at lowering time, it should always
be concrete after substitution.

Fixes #106230
  • Loading branch information
maurer committed Dec 29, 2022
1 parent 270c94e commit fb2c27d
Show file tree
Hide file tree
Showing 2 changed files with 23 additions and 4 deletions.
Original file line number Diff line number Diff line change
Expand Up @@ -164,6 +164,7 @@ fn encode_const<'tcx>(

/// Encodes a FnSig using the Itanium C++ ABI with vendor extended type qualifiers and types for
/// Rust types that are not used at the FFI boundary.
#[instrument(level = "trace", skip(tcx, dict))]
fn encode_fnsig<'tcx>(
tcx: TyCtxt<'tcx>,
fn_sig: &FnSig<'tcx>,
Expand Down Expand Up @@ -653,6 +654,7 @@ fn encode_ty<'tcx>(
// Transforms a ty:Ty for being encoded and used in the substitution dictionary. It transforms all
// c_void types into unit types unconditionally, and generalizes all pointers if
// TransformTyOptions::GENERALIZE_POINTERS option is set.
#[instrument(level = "trace", skip(tcx))]
fn transform_ty<'tcx>(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>, options: TransformTyOptions) -> Ty<'tcx> {
let mut ty = ty;

Expand Down Expand Up @@ -698,7 +700,7 @@ fn transform_ty<'tcx>(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>, options: TransformTyOptio
!is_zst
});
if let Some(field) = field {
let ty0 = tcx.type_of(field.did);
let ty0 = tcx.bound_type_of(field.did).subst(tcx, substs);
// Generalize any repr(transparent) user-defined type that is either a pointer
// or reference, and either references itself or any other type that contains or
// references itself, to avoid a reference cycle.
Expand Down Expand Up @@ -827,6 +829,7 @@ fn transform_substs<'tcx>(

/// Returns a type metadata identifier for the specified FnAbi using the Itanium C++ ABI with vendor
/// extended type qualifiers and types for Rust types that are not used at the FFI boundary.
#[instrument(level = "trace", skip(tcx))]
pub fn typeid_for_fnabi<'tcx>(
tcx: TyCtxt<'tcx>,
fn_abi: &FnAbi<'tcx, Ty<'tcx>>,
Expand Down
Original file line number Diff line number Diff line change
Expand Up @@ -131,6 +131,13 @@ pub struct Type13<'a> {
member3: &'a Type13<'a>,
}

// Helper type to allow `Type14<Bar>` to be a unique ID
pub struct Bar;

// repr(transparent) parameterized type
#[repr(transparent)]
pub struct Type14<T>(T);

pub fn foo0(_: ()) { }
// CHECK: define{{.*}}foo0{{.*}}!type ![[TYPE0:[0-9]+]]
pub fn foo1(_: c_void, _: ()) { }
Expand Down Expand Up @@ -425,6 +432,12 @@ pub fn foo145(_: Type13, _: Type13) { }
// CHECK: define{{.*}}foo145{{.*}}!type ![[TYPE145:[0-9]+]]
pub fn foo146(_: Type13, _: Type13, _: Type13) { }
// CHECK: define{{.*}}foo146{{.*}}!type ![[TYPE146:[0-9]+]]
pub fn foo147(_: Type14<Bar>) { }
// CHECK: define{{.*}}foo147{{.*}}!type ![[TYPE147:[0-9]+]]
pub fn foo148(_: Type14<Bar>, _: Type14<Bar>) { }
// CHECK: define{{.*}}foo148{{.*}}!type ![[TYPE148:[0-9]+]]
pub fn foo149(_: Type14<Bar>, _: Type14<Bar>, _: Type14<Bar>) { }
// CHECK: define{{.*}}foo149{{.*}}!type ![[TYPE149:[0-9]+]]

// CHECK: ![[TYPE0]] = !{i64 0, !"_ZTSFvvE"}
// CHECK: ![[TYPE1]] = !{i64 0, !"_ZTSFvvvE"}
Expand Down Expand Up @@ -570,6 +583,9 @@ pub fn foo146(_: Type13, _: Type13, _: Type13) { }
// CHECK: ![[TYPE141]] = !{i64 0, !"_ZTSFvu{{[0-9]+}}NtC{{[[:print:]]+}}_51sanitizer_cfi_emit_type_metadata_id_itanium_cxx_abi3FooE"}
// CHECK: ![[TYPE142]] = !{i64 0, !"_ZTSFvu{{[0-9]+}}NtC{{[[:print:]]+}}_51sanitizer_cfi_emit_type_metadata_id_itanium_cxx_abi3FooS_E"}
// CHECK: ![[TYPE143]] = !{i64 0, !"_ZTSFvu{{[0-9]+}}NtC{{[[:print:]]+}}_51sanitizer_cfi_emit_type_metadata_id_itanium_cxx_abi3FooS_S_E"}
// CHECK: ![[TYPE144]] = !{i64 0, !"_ZTSFvu3refIu3refIvEEE"}
// CHECK: ![[TYPE145]] = !{i64 0, !"_ZTSFvu3refIu3refIvEES0_E"}
// CHECK: ![[TYPE146]] = !{i64 0, !"_ZTSFvu3refIu3refIvEES0_S0_E"}
// CHECK: ![[TYPE144]] = !{i64 0, !"_ZTSFvu3refIvEE"}
// CHECK: ![[TYPE145]] = !{i64 0, !"_ZTSFvu3refIvES_E"}
// CHECK: ![[TYPE146]] = !{i64 0, !"_ZTSFvu3refIvES_S_E"}
// CHECK: ![[TYPE147]] = !{i64 0, !"_ZTSFvu{{[0-9]+}}NtC{{[[:print:]]+}}_51sanitizer_cfi_emit_type_metadata_id_itanium_cxx_abi3BarE
// CHECK: ![[TYPE148]] = !{i64 0, !"_ZTSFvu{{[0-9]+}}NtC{{[[:print:]]+}}_51sanitizer_cfi_emit_type_metadata_id_itanium_cxx_abi3BarS_E
// CHECK: ![[TYPE149]] = !{i64 0, !"_ZTSFvu{{[0-9]+}}NtC{{[[:print:]]+}}_51sanitizer_cfi_emit_type_metadata_id_itanium_cxx_abi3BarS_S_E

0 comments on commit fb2c27d

Please sign in to comment.