]> git.proxmox.com Git - rustc.git/blobdiff - compiler/rustc_ty_utils/src/abi.rs
New upstream version 1.69.0+dfsg1
[rustc.git] / compiler / rustc_ty_utils / src / abi.rs
index 91a505a72fae7a6be74b31e2b2ff0909af29b877..35c9f95eb03b1b71fd3d103372b0497494394924 100644 (file)
@@ -41,7 +41,7 @@ fn fn_sig_for_fn_abi<'tcx>(
             // We normalize the `fn_sig` again after substituting at a later point.
             let mut sig = match *ty.kind() {
                 ty::FnDef(def_id, substs) => tcx
-                    .bound_fn_sig(def_id)
+                    .fn_sig(def_id)
                     .map_bound(|fn_sig| {
                         tcx.normalize_erasing_regions(tcx.param_env(def_id), fn_sig)
                     })
@@ -54,7 +54,7 @@ fn fn_sig_for_fn_abi<'tcx>(
                 sig = sig.map_bound(|mut sig| {
                     let mut inputs_and_output = sig.inputs_and_output.to_vec();
                     inputs_and_output[0] = tcx.mk_mut_ptr(inputs_and_output[0]);
-                    sig.inputs_and_output = tcx.intern_type_list(&inputs_and_output);
+                    sig.inputs_and_output = tcx.mk_type_list(&inputs_and_output);
                     sig
                 });
             }
@@ -63,14 +63,14 @@ fn fn_sig_for_fn_abi<'tcx>(
         ty::Closure(def_id, substs) => {
             let sig = substs.as_closure().sig();
 
-            let bound_vars = tcx.mk_bound_variable_kinds(
+            let bound_vars = tcx.mk_bound_variable_kinds_from_iter(
                 sig.bound_vars().iter().chain(iter::once(ty::BoundVariableKind::Region(ty::BrEnv))),
             );
             let br = ty::BoundRegion {
                 var: ty::BoundVar::from_usize(bound_vars.len() - 1),
                 kind: ty::BoundRegionKind::BrEnv,
             };
-            let env_region = ty::ReLateBound(ty::INNERMOST, br);
+            let env_region = tcx.mk_re_late_bound(ty::INNERMOST, br);
             let env_ty = tcx.closure_env_ty(def_id, substs, env_region).unwrap();
 
             let sig = sig.skip_binder();
@@ -88,19 +88,18 @@ fn fn_sig_for_fn_abi<'tcx>(
         ty::Generator(did, substs, _) => {
             let sig = substs.as_generator().poly_sig();
 
-            let bound_vars = tcx.mk_bound_variable_kinds(
+            let bound_vars = tcx.mk_bound_variable_kinds_from_iter(
                 sig.bound_vars().iter().chain(iter::once(ty::BoundVariableKind::Region(ty::BrEnv))),
             );
             let br = ty::BoundRegion {
                 var: ty::BoundVar::from_usize(bound_vars.len() - 1),
                 kind: ty::BoundRegionKind::BrEnv,
             };
-            let env_region = ty::ReLateBound(ty::INNERMOST, br);
-            let env_ty = tcx.mk_mut_ref(tcx.mk_region(env_region), ty);
+            let env_ty = tcx.mk_mut_ref(tcx.mk_re_late_bound(ty::INNERMOST, br), ty);
 
             let pin_did = tcx.require_lang_item(LangItem::Pin, None);
             let pin_adt_ref = tcx.adt_def(pin_did);
-            let pin_substs = tcx.intern_substs(&[env_ty.into()]);
+            let pin_substs = tcx.mk_substs(&[env_ty.into()]);
             let env_ty = tcx.mk_adt(pin_adt_ref, pin_substs);
 
             let sig = sig.skip_binder();
@@ -112,7 +111,7 @@ fn fn_sig_for_fn_abi<'tcx>(
                 // The signature should be `Future::poll(_, &mut Context<'_>) -> Poll<Output>`
                 let poll_did = tcx.require_lang_item(LangItem::Poll, None);
                 let poll_adt_ref = tcx.adt_def(poll_did);
-                let poll_substs = tcx.intern_substs(&[sig.return_ty.into()]);
+                let poll_substs = tcx.mk_substs(&[sig.return_ty.into()]);
                 let ret_ty = tcx.mk_adt(poll_adt_ref, poll_substs);
 
                 // We have to replace the `ResumeTy` that is used for type and borrow checking
@@ -134,7 +133,7 @@ fn fn_sig_for_fn_abi<'tcx>(
                 // The signature should be `Generator::resume(_, Resume) -> GeneratorState<Yield, Return>`
                 let state_did = tcx.require_lang_item(LangItem::GeneratorState, None);
                 let state_adt_ref = tcx.adt_def(state_did);
-                let state_substs = tcx.intern_substs(&[sig.yield_ty.into(), sig.return_ty.into()]);
+                let state_substs = tcx.mk_substs(&[sig.yield_ty.into(), sig.return_ty.into()]);
                 let ret_ty = tcx.mk_adt(state_adt_ref, state_substs);
 
                 (sig.resume_ty, ret_ty)
@@ -142,8 +141,8 @@ fn fn_sig_for_fn_abi<'tcx>(
 
             ty::Binder::bind_with_vars(
                 tcx.mk_fn_sig(
-                    [env_ty, resume_ty].iter(),
-                    &ret_ty,
+                    [env_ty, resume_ty],
+                    ret_ty,
                     false,
                     hir::Unsafety::Normal,
                     rustc_target::spec::abi::Abi::Rust,
@@ -207,11 +206,8 @@ fn fn_abi_of_instance<'tcx>(
 
     let sig = fn_sig_for_fn_abi(tcx, instance, param_env);
 
-    let caller_location = if instance.def.requires_caller_location(tcx) {
-        Some(tcx.caller_location_ty())
-    } else {
-        None
-    };
+    let caller_location =
+        instance.def.requires_caller_location(tcx).then(|| tcx.caller_location_ty());
 
     fn_abi_new_uncached(
         &LayoutCx { tcx, param_env },
@@ -244,7 +240,7 @@ fn adjust_for_rust_scalar<'tcx>(
     }
 
     // Only pointer types handled below.
-    let Scalar::Initialized { value: Pointer, valid_range} = scalar else { return };
+    let Scalar::Initialized { value: Pointer(_), valid_range} = scalar else { return };
 
     if !valid_range.contains(0) {
         attrs.set(ArgAttribute::NonNull);
@@ -254,15 +250,18 @@ fn adjust_for_rust_scalar<'tcx>(
         if let Some(kind) = pointee.safe {
             attrs.pointee_align = Some(pointee.align);
 
-            // `Box` (`UniqueBorrowed`) are not necessarily dereferenceable
-            // for the entire duration of the function as they can be deallocated
-            // at any time. Same for shared mutable references. If LLVM had a
-            // way to say "dereferenceable on entry" we could use it here.
+            // `Box` are not necessarily dereferenceable for the entire duration of the function as
+            // they can be deallocated at any time. Same for non-frozen shared references (see
+            // <https://github.com/rust-lang/rust/pull/98017>), and for mutable references to
+            // potentially self-referential types (see
+            // <https://github.com/rust-lang/unsafe-code-guidelines/issues/381>). If LLVM had a way
+            // to say "dereferenceable on entry" we could use it here.
             attrs.pointee_size = match kind {
-                PointerKind::UniqueBorrowed
-                | PointerKind::UniqueBorrowedPinned
-                | PointerKind::Frozen => pointee.size,
-                PointerKind::SharedMutable | PointerKind::UniqueOwned => Size::ZERO,
+                PointerKind::Box { .. }
+                | PointerKind::SharedRef { frozen: false }
+                | PointerKind::MutableRef { unpin: false } => Size::ZERO,
+                PointerKind::SharedRef { frozen: true }
+                | PointerKind::MutableRef { unpin: true } => pointee.size,
             };
 
             // The aliasing rules for `Box<T>` are still not decided, but currently we emit
@@ -275,18 +274,16 @@ fn adjust_for_rust_scalar<'tcx>(
             // versions at all anymore. We still support turning it off using -Zmutable-noalias.
             let noalias_mut_ref = cx.tcx.sess.opts.unstable_opts.mutable_noalias;
 
-            // `&mut` pointer parameters never alias other parameters,
-            // or mutable global data
+            // `&T` where `T` contains no `UnsafeCell<U>` is immutable, and can be marked as both
+            // `readonly` and `noalias`, as LLVM's definition of `noalias` is based solely on memory
+            // dependencies rather than pointer equality. However this only applies to arguments,
+            // not return values.
             //
-            // `&T` where `T` contains no `UnsafeCell<U>` is immutable,
-            // and can be marked as both `readonly` and `noalias`, as
-            // LLVM's definition of `noalias` is based solely on memory
-            // dependencies rather than pointer equality
+            // `&mut T` and `Box<T>` where `T: Unpin` are unique and hence `noalias`.
             let no_alias = match kind {
-                PointerKind::SharedMutable | PointerKind::UniqueBorrowedPinned => false,
-                PointerKind::UniqueBorrowed => noalias_mut_ref,
-                PointerKind::UniqueOwned => noalias_for_box,
-                PointerKind::Frozen => true,
+                PointerKind::SharedRef { frozen } => frozen,
+                PointerKind::MutableRef { unpin } => unpin && noalias_mut_ref,
+                PointerKind::Box { unpin } => unpin && noalias_for_box,
             };
             // We can never add `noalias` in return position; that LLVM attribute has some very surprising semantics
             // (see <https://github.com/rust-lang/unsafe-code-guidelines/issues/385#issuecomment-1368055745>).
@@ -294,7 +291,7 @@ fn adjust_for_rust_scalar<'tcx>(
                 attrs.set(ArgAttribute::NoAlias);
             }
 
-            if kind == PointerKind::Frozen && !is_return {
+            if matches!(kind, PointerKind::SharedRef { frozen: true }) && !is_return {
                 attrs.set(ArgAttribute::ReadOnly);
             }
         }
@@ -479,7 +476,7 @@ fn fn_abi_adjust_for_abi<'tcx>(
             }
 
             let size = arg.layout.size;
-            if arg.layout.is_unsized() || size > Pointer.size(cx) {
+            if arg.layout.is_unsized() || size > Pointer(AddressSpace::DATA).size(cx) {
                 arg.make_indirect();
             } else {
                 // We want to pass small aggregates as immediates, but using