Auto merge of #132460 - lcnr:questionable-uwu, r=compiler-errors

Use `TypingMode` throughout the compiler instead of `ParamEnv`

Hopefully the biggest single PR as part of https://github.com/rust-lang/types-team/issues/128.

## `infcx.typing_env` while defining opaque types

I don't know how'll be able to correctly handle opaque types when using something taking a `TypingEnv` while defining opaque types. To correctly handle the opaques we need to be able to pass in the current `opaque_type_storage` and return constraints, i.e. we need to use a proper canonical query. We should migrate all the queries used during HIR typeck and borrowck where this matters to proper canonical queries. This is

## `layout_of` and `Reveal::All`

We convert the `ParamEnv` to `Reveal::All` right at the start of the `layout_of` query, so I've changed callers of `layout_of` to already use a post analysis `TypingEnv` when encountering it.

https://github.com/rust-lang/rust/blob/ca87b535a05097df6abbe2a031b057de2cefac5b/compiler/rustc_ty_utils/src/layout.rs#L51

## `Ty::is_[unpin|sized|whatever]`

I haven't migrated `fn is_item_raw` to use `TypingEnv`, will do so in a followup PR, this should significantly reduce the amount of `typing_env.param_env`. At some point there will probably be zero such uses as using the type system while ignoring the `typing_mode` is incorrect.

## `MirPhase` and phase-transitions

When inside of a MIR-body, we can mostly use its `MirPhase` to figure out the right `typing_mode`. This does not work during phase transitions, most notably when transitioning from `Analysis` to `Runtime`:

https://github.com/rust-lang/rust/blob/dae7ac133b9eda152784c075facb31a6688c92b1/compiler/rustc_mir_transform/src/lib.rs#L606-L625

All these passes still run with `MirPhase::Analysis`, but we should only use `Reveal::All` once we're run the `RevealAll` pass. This required me to manually construct the right `TypingEnv` in all these passes. Given that it feels somewhat easy to accidentally miss this going forward, I would maybe like to change `Body::phase` to an `Option` and replace it at the start of phase transitions. This then makes it clear that the MIR is currently in a weird state.

r? `@ghost`

1 files changed, 19 insertions, 7 deletions

diff --git a/compiler/rustc_codegen_llvm/src/debuginfo/metadata/type_map.rs b/compiler/rustc_codegen_llvm/src/debuginfo/metadata/type_map.rs
index 5120b63d173..4e461476040 100644
--- a/compiler/rustc_codegen_llvm/src/debuginfo/metadata/type_map.rs
+++ b/compiler/rustc_codegen_llvm/src/debuginfo/metadata/type_map.rs
@@ -6,7 +6,7 @@ use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
 use rustc_macros::HashStable;
 use rustc_middle::bug;
-use rustc_middle::ty::{ParamEnv, PolyExistentialTraitRef, Ty, TyCtxt};
+use rustc_middle::ty::{self, PolyExistentialTraitRef, Ty, TyCtxt};
 
 use super::{SmallVec, UNKNOWN_LINE_NUMBER, unknown_file_metadata};
 use crate::common::{AsCCharPtr, CodegenCx};
@@ -49,12 +49,15 @@ pub(super) enum UniqueTypeId<'tcx> {
 
 impl<'tcx> UniqueTypeId<'tcx> {
     pub(crate) fn for_ty(tcx: TyCtxt<'tcx>, t: Ty<'tcx>) -> Self {
-        assert_eq!(t, tcx.normalize_erasing_regions(ParamEnv::reveal_all(), t));
+        assert_eq!(t, tcx.normalize_erasing_regions(ty::TypingEnv::fully_monomorphized(), t));
         UniqueTypeId::Ty(t, private::HiddenZst)
     }
 
     pub(crate) fn for_enum_variant_part(tcx: TyCtxt<'tcx>, enum_ty: Ty<'tcx>) -> Self {
-        assert_eq!(enum_ty, tcx.normalize_erasing_regions(ParamEnv::reveal_all(), enum_ty));
+        assert_eq!(
+            enum_ty,
+            tcx.normalize_erasing_regions(ty::TypingEnv::fully_monomorphized(), enum_ty)
+        );
         UniqueTypeId::VariantPart(enum_ty, private::HiddenZst)
     }
 
@@ -63,7 +66,10 @@ impl<'tcx> UniqueTypeId<'tcx> {
         enum_ty: Ty<'tcx>,
         variant_idx: VariantIdx,
     ) -> Self {
-        assert_eq!(enum_ty, tcx.normalize_erasing_regions(ParamEnv::reveal_all(), enum_ty));
+        assert_eq!(
+            enum_ty,
+            tcx.normalize_erasing_regions(ty::TypingEnv::fully_monomorphized(), enum_ty)
+        );
         UniqueTypeId::VariantStructType(enum_ty, variant_idx, private::HiddenZst)
     }
 
@@ -72,7 +78,10 @@ impl<'tcx> UniqueTypeId<'tcx> {
         enum_ty: Ty<'tcx>,
         variant_idx: VariantIdx,
     ) -> Self {
-        assert_eq!(enum_ty, tcx.normalize_erasing_regions(ParamEnv::reveal_all(), enum_ty));
+        assert_eq!(
+            enum_ty,
+            tcx.normalize_erasing_regions(ty::TypingEnv::fully_monomorphized(), enum_ty)
+        );
         UniqueTypeId::VariantStructTypeCppLikeWrapper(enum_ty, variant_idx, private::HiddenZst)
     }
 
@@ -81,10 +90,13 @@ impl<'tcx> UniqueTypeId<'tcx> {
         self_type: Ty<'tcx>,
         implemented_trait: Option<PolyExistentialTraitRef<'tcx>>,
     ) -> Self {
-        assert_eq!(self_type, tcx.normalize_erasing_regions(ParamEnv::reveal_all(), self_type));
+        assert_eq!(
+            self_type,
+            tcx.normalize_erasing_regions(ty::TypingEnv::fully_monomorphized(), self_type)
+        );
         assert_eq!(
             implemented_trait,
-            tcx.normalize_erasing_regions(ParamEnv::reveal_all(), implemented_trait)
+            tcx.normalize_erasing_regions(ty::TypingEnv::fully_monomorphized(), implemented_trait)
         );
         UniqueTypeId::VTableTy(self_type, implemented_trait, private::HiddenZst)
     }