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, 17 insertions, 14 deletions

diff --git a/compiler/rustc_codegen_ssa/src/debuginfo/type_names.rs b/compiler/rustc_codegen_ssa/src/debuginfo/type_names.rs
index 27bc58516c0..6c4f6d37972 100644
--- a/compiler/rustc_codegen_ssa/src/debuginfo/type_names.rs
+++ b/compiler/rustc_codegen_ssa/src/debuginfo/type_names.rs
@@ -21,9 +21,7 @@ use rustc_hir::definitions::{DefPathData, DefPathDataName, DisambiguatedDefPathD
 use rustc_hir::{CoroutineDesugaring, CoroutineKind, CoroutineSource, Mutability};
 use rustc_middle::bug;
 use rustc_middle::ty::layout::{IntegerExt, TyAndLayout};
-use rustc_middle::ty::{
-    self, ExistentialProjection, GenericArgKind, GenericArgsRef, ParamEnv, Ty, TyCtxt,
-};
+use rustc_middle::ty::{self, ExistentialProjection, GenericArgKind, GenericArgsRef, Ty, TyCtxt};
 use smallvec::SmallVec;
 
 use crate::debuginfo::wants_c_like_enum_debuginfo;
@@ -82,7 +80,7 @@ fn push_debuginfo_type_name<'tcx>(
         ty::Adt(def, args) => {
             // `layout_for_cpp_like_fallback` will be `Some` if we want to use the fallback encoding.
             let layout_for_cpp_like_fallback = if cpp_like_debuginfo && def.is_enum() {
-                match tcx.layout_of(ParamEnv::reveal_all().and(t)) {
+                match tcx.layout_of(ty::TypingEnv::fully_monomorphized().as_query_input(t)) {
                     Ok(layout) => {
                         if !wants_c_like_enum_debuginfo(tcx, layout) {
                             Some(layout)
@@ -248,8 +246,10 @@ fn push_debuginfo_type_name<'tcx>(
             };
 
             if let Some(principal) = trait_data.principal() {
-                let principal =
-                    tcx.normalize_erasing_late_bound_regions(ty::ParamEnv::reveal_all(), principal);
+                let principal = tcx.normalize_erasing_late_bound_regions(
+                    ty::TypingEnv::fully_monomorphized(),
+                    principal,
+                );
                 push_item_name(tcx, principal.def_id, qualified, output);
                 let principal_has_generic_params =
                     push_generic_params_internal(tcx, principal.args, output, visited);
@@ -350,8 +350,10 @@ fn push_debuginfo_type_name<'tcx>(
                 return;
             }
 
-            let sig =
-                tcx.normalize_erasing_late_bound_regions(ty::ParamEnv::reveal_all(), t.fn_sig(tcx));
+            let sig = tcx.normalize_erasing_late_bound_regions(
+                ty::TypingEnv::fully_monomorphized(),
+                t.fn_sig(tcx),
+            );
 
             if cpp_like_debuginfo {
                 // Format as a C++ function pointer: return_type (*)(params...)
@@ -415,7 +417,8 @@ fn push_debuginfo_type_name<'tcx>(
             // In the case of cpp-like debuginfo, the name additionally gets wrapped inside of
             // an artificial `enum2$<>` type, as defined in msvc_enum_fallback().
             if cpp_like_debuginfo && t.is_coroutine() {
-                let ty_and_layout = tcx.layout_of(ParamEnv::reveal_all().and(t)).unwrap();
+                let ty_and_layout =
+                    tcx.layout_of(ty::TypingEnv::fully_monomorphized().as_query_input(t)).unwrap();
                 msvc_enum_fallback(
                     tcx,
                     ty_and_layout,
@@ -529,8 +532,8 @@ pub fn compute_debuginfo_vtable_name<'tcx>(
     }
 
     if let Some(trait_ref) = trait_ref {
-        let trait_ref =
-            tcx.normalize_erasing_late_bound_regions(ty::ParamEnv::reveal_all(), trait_ref);
+        let trait_ref = tcx
+            .normalize_erasing_late_bound_regions(ty::TypingEnv::fully_monomorphized(), trait_ref);
         push_item_name(tcx, trait_ref.def_id, true, &mut vtable_name);
         visited.clear();
         push_generic_params_internal(tcx, trait_ref.args, &mut vtable_name, &mut visited);
@@ -639,7 +642,7 @@ fn push_generic_params_internal<'tcx>(
     output: &mut String,
     visited: &mut FxHashSet<Ty<'tcx>>,
 ) -> bool {
-    assert_eq!(args, tcx.normalize_erasing_regions(ty::ParamEnv::reveal_all(), args));
+    assert_eq!(args, tcx.normalize_erasing_regions(ty::TypingEnv::fully_monomorphized(), args));
     let mut args = args.non_erasable_generics().peekable();
     if args.peek().is_none() {
         return false;
@@ -678,14 +681,14 @@ fn push_const_param<'tcx>(tcx: TyCtxt<'tcx>, ct: ty::Const<'tcx>, output: &mut S
                     // FIXME: directly extract the bits from a valtree instead of evaluating an
                     // already evaluated `Const` in order to get the bits.
                     let bits = ct
-                        .try_to_bits(tcx, ty::ParamEnv::reveal_all())
+                        .try_to_bits(tcx, ty::TypingEnv::fully_monomorphized())
                         .expect("expected monomorphic const in codegen");
                     let val = Integer::from_int_ty(&tcx, *ity).size().sign_extend(bits) as i128;
                     write!(output, "{val}")
                 }
                 ty::Uint(_) => {
                     let val = ct
-                        .try_to_bits(tcx, ty::ParamEnv::reveal_all())
+                        .try_to_bits(tcx, ty::TypingEnv::fully_monomorphized())
                         .expect("expected monomorphic const in codegen");
                     write!(output, "{val}")
                 }