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, 5 insertions, 5 deletions

diff --git a/compiler/rustc_codegen_llvm/src/context.rs b/compiler/rustc_codegen_llvm/src/context.rs
index 3a7c7efe03b..841c110b3c8 100644
--- a/compiler/rustc_codegen_llvm/src/context.rs
+++ b/compiler/rustc_codegen_llvm/src/context.rs
@@ -15,7 +15,7 @@ use rustc_hir::def_id::DefId;
 use rustc_middle::middle::codegen_fn_attrs::PatchableFunctionEntry;
 use rustc_middle::mir::mono::CodegenUnit;
 use rustc_middle::ty::layout::{
-    FnAbiError, FnAbiOfHelpers, FnAbiRequest, HasParamEnv, LayoutError, LayoutOfHelpers,
+    FnAbiError, FnAbiOfHelpers, FnAbiRequest, HasTypingEnv, LayoutError, LayoutOfHelpers,
 };
 use rustc_middle::ty::{self, Instance, Ty, TyCtxt};
 use rustc_middle::{bug, span_bug};
@@ -658,7 +658,7 @@ impl<'ll, 'tcx> MiscCodegenMethods<'tcx> for CodegenCx<'ll, 'tcx> {
         let llfn = match tcx.lang_items().eh_personality() {
             Some(def_id) if name.is_none() => self.get_fn_addr(ty::Instance::expect_resolve(
                 tcx,
-                ty::ParamEnv::reveal_all(),
+                self.typing_env(),
                 def_id,
                 ty::List::empty(),
                 DUMMY_SP,
@@ -1162,9 +1162,9 @@ impl<'tcx> ty::layout::HasTyCtxt<'tcx> for CodegenCx<'_, 'tcx> {
     }
 }
 
-impl<'tcx, 'll> HasParamEnv<'tcx> for CodegenCx<'ll, 'tcx> {
-    fn param_env(&self) -> ty::ParamEnv<'tcx> {
-        ty::ParamEnv::reveal_all()
+impl<'tcx, 'll> HasTypingEnv<'tcx> for CodegenCx<'ll, 'tcx> {
+    fn typing_env(&self) -> ty::TypingEnv<'tcx> {
+        ty::TypingEnv::fully_monomorphized()
     }
 }