CFI: Monomorphize transparent ADTs before typeid

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

compiler/rustc_symbol_mangling/src/typeid/typeid_itanium_cxx_abi.rs

@@ -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>,
@@ -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;
 
@@ -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.
@@ -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>>,

src/test/codegen/sanitizer-cfi-emit-type-metadata-id-itanium-cxx-abi.rs

@@ -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, _: ()) { }
@@ -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"}
@@ -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